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Code Activity

Sls (#7439)

Browse source 
* reorg sls

* sls

* na

* split into base and plugin

* move sat_params to params directory, add op_def repair options

* move sat_ddfw to sls, initiate sls-bv-plugin

* porting bv-sls

* adding basic plugin

* na

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* add sls-sms solver

* bv updates

* updated dependencies

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* updated dependencies

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* use portable ptr-initializer

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* move definitions to cpp

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* use template<> syntax

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fix compiler errors for gcc

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* Bump docker/build-push-action from 6.0.0 to 6.1.0 (#7265)

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 6.0.0 to 6.1.0.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](https://github.com/docker/build-push-action/compare/v6.0.0...v6.1.0)

---
updated-dependencies:
- dependency-name: docker/build-push-action
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

* set clean shutdown for local search and re-enable local search when it parallelizes with PB solver

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* Bump docker/build-push-action from 6.1.0 to 6.2.0 (#7269)

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 6.1.0 to 6.2.0.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](https://github.com/docker/build-push-action/compare/v6.1.0...v6.2.0)

---
updated-dependencies:
- dependency-name: docker/build-push-action
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

* Fix a comment for Z3_solver_from_string (#7271)

Z3_solver_from_string accepts a string buffer with solver
assertions, not a string buffer with filename.

* trigger the build with a comment change

Signed-off-by: Lev Nachmanson <levnach@hotmail.com>

* remove macro distinction #7270

* fix #7268

* kludge to address #7232, probably superseeded by planned revision to setup/pypi

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* add new ema invariant (#7288)

* Bump docker/build-push-action from 6.2.0 to 6.3.0 (#7280)

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 6.2.0 to 6.3.0.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](https://github.com/docker/build-push-action/compare/v6.2.0...v6.3.0)

---
updated-dependencies:
- dependency-name: docker/build-push-action
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

* merge

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fix unit test build

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* remove shared attribute

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* remove stale files

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fix build of unit test

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixes and rename sls-cc to sls-euf-plugin

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* na

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* testing / debugging arithmetic

* updates to repair logic, mainly arithmetic

* fixes to sls

* evolve sls arith

* bugfixes in sls-arith

* fix typo

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* bug fixes

* Update sls_test.cpp

* fixes

* fixes

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fix build

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* refactor basic plugin and clause generation

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixes to ite and other

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* updates

* update

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fix division by 0

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* disable fail restart

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* disable tabu when using reset moves

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* update sls_test

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* add factoring

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixes to semantics

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* re-add tabu override

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* generalize factoring

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fix bug

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* remove restart

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* disable tabu in fallback modes

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* localize impact of factoring

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* delay factoring

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* flatten products

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* perform lookahead update + nested mul

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* disable nested mul

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* disable nested mul, use non-lookahead

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* make reset updates recursive

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* include linear moves

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* include 5% reset probability

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* separate linear update

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* separate linear update remove 20% threshold

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* remove linear opt

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* enable multiplier expansion, enable linear move

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* use unit coefficients for muls

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* disable non-tabu version of find_nl_moves

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* remove coefficient from multiplication definition

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* reorg monomials

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* add smt params to path

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* avoid negative reward

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* use reward as proxy for score

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* use reward as proxy for score

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* use exponential decay with breaks

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* use std::pow

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixes to bv

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixes to fixed

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixup repairs

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* reserve for multiplication

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixing repair

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* include bounds checks in set random

* na

* fixes to mul

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fix mul inverse

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixes to handling signed operators

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* logging and fixes

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* gcm

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* peli

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* Add .env to gitignore to prevent environment files from being tracked

* Add m_num_pelis counter to stats in sls_context

* Remove m_num_pelis member from stats struct in sls_context

* Enhance bv_sls_eval with improved repair and logging, refine is_bv_predicate in sls_bv_plugin

* Remove verbose logging in register_term function of sls_basic_plugin and fix formatting in sls_context

* Rename source files for consistency in `src/ast/sls` directory

* Refactor bv_sls files to sls_bv with namespace and class name adjustments

* Remove typename from member declarations in bv_fixed class

* fixing conca

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* Add initial implementation of bit-vector SLS evaluation module in bv_sls_eval.cpp

* Remove bv_sls_eval.cpp as part of code cleanup and refactoring

* Refactor alignment of member variables in bv_plugin of sls namespace

* Rename SLS engine related files to reflect their specific use for bit-vectors

* Refactor SLS engine and evaluator components for bit-vector specifics and adjust memory manager alignment

* Enhance bv_eval with use_current, lookahead strategies, and randomization improvements in SLS module

* Refactor verbose logging and fix logic in range adjustment functions in sls bv modules

* Remove commented verbose output in sls_bv_plugin.cpp during repair process

* Add early return after setting fixed subterms in sls_bv_fixed.cpp

* Remove redundant return statement in sls_bv_fixed.cpp

* fixes to new value propagation

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* Refactor sls bv evaluation and fix logic checks for bit operations

* Add array plugin support and update bv_eval in ast_sls module

* Add array, model value, and user sort plugins to SLS module with enhancements in array propagation logic

* Refactor array_plugin in sls to improve handling of select expressions with multiple arguments

* Enhance array plugin with early termination and propagation verification, and improve euf and user sort plugins with propagation adjustments and debugging enhancements

* Add support for handling 'distinct' expressions in SLS context and user sort plugin

* Remove model value and user sort plugins from SLS theory

* replace user plugin by euf plugin

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* remove extra file

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* Refactor handling of term registration and enhance distinct handling in sls_euf_plugin

* Add TODO list for enhancements in sls_euf_plugin.cpp

* add incremental mode

* updated package

* fix sls build

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* break sls build

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fix build

* break build again

* fix build

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixes

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixing incremental

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* avoid units

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixup handling of disequality propagation

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fx

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* recover shift-weight loop

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* alternate

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* throttle save model

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* allow for alternating

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fix test for new signature of flip

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* bug fixes

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* restore use of value_hash

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixes

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* adding dt plugin

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* adt

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* dt updates

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* added cycle detection

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* updated sls-datatype

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* Refactor context management, improve datatype handling, and enhance logging in sls plugins.

* axiomatize dt

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* add missing factory plugins to model

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixup finite domain search

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixup finite domain search

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixes

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* redo dfs

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixing model construction for underspecified operators

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixes to occurs check

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixup interpretation building

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* saturate worklist

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* delay distinct axiom

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* adding model-based sls for datatatypes

* update the interface in sls_solver to transfer phase between SAT and SLS

* add value transfer option

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* rename aux functions

* Track shared variables using a unit set

* debugging parallel integration

* fix dirty flag setting

* update log level

* add plugin to smt_context, factor out sls_smt_plugin functionality.

* bug fixes

* fixes

* use common infrastructure for sls-smt

* fix build

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fix build

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* remove declaration of context

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* add virtual destructor

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* build warnings

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* reorder inclusion order to define smt_context before theory_sls

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* change namespace for single threaded

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* check delayed eqs before nla

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* use independent completion flag for sls to avoid conflating with genuine cancelation

* validate sls-arith lemmas

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* bugfixes

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* add intblast to legacy SMT solver

* fixup model generation for theory_intblast

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* na

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* mk_value needs to accept more cases where integer expression doesn't evalate

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* use th-axioms to track origins of assertions

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* add missing operator handling for bitwise operators

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* add missing operator handling for bitwise operators

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* normalizing inequality

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* add virtual destructor

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* rework elim_unconstrained

* fix non-termination

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* use glue as computed without adjustment

* update model generation to fix model bug

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fixes to model construction

* remove package and package lock

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* fix build warning

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* use original gai

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

---------

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
Signed-off-by: dependabot[bot] <support@github.com>
Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Sergey Bronnikov <estetus@gmail.com>
Co-authored-by: Lev Nachmanson <levnach@hotmail.com>
Co-authored-by: LiviaSun <33578456+ChuyueSun@users.noreply.github.com>
This commit is contained in:
Nikolaj Bjorner 2024-11-02 12:32:48 -07:00 committed by GitHub
parent ecdfab81a6
commit 91dc02d862
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GPG key ID: B5690EEEBB952194
120 changed files with 11172 additions and 4148 deletions
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4
.gitignore vendored
View file

@ -6,6 +6,7 @@ rebase.cmd
callgrind.out.*
# .hpp files are automatically generated
*.hpp
.env
.z3-trace
.env
.genaiscript
@ -28,6 +29,8 @@ ocamlz3
# Emacs temp files
\#*\#
# Directories with generated code and documentation
node_modules/*
.genaiscript/*
release/*
build/*
trace/*
@ -105,3 +108,4 @@ CMakeSettings.json
.DS_Store
dbg/**
*.wsp
CppProperties.json

14
scripts/mk_project.py
View file

@ -28,19 +28,19 @@ def init_project_def():
add_lib('parser_util', ['ast'], 'parsers/util')
add_lib('euf', ['ast'], 'ast/euf')
add_lib('grobner', ['ast', 'dd', 'simplex'], 'math/grobner')
add_lib('sat', ['params', 'util', 'dd', 'grobner'])
add_lib('nlsat', ['polynomial', 'sat'])
add_lib('lp', ['util', 'nlsat', 'grobner', 'interval', 'smt_params'], 'math/lp')
add_lib('rewriter', ['ast', 'polynomial', 'interval', 'automata', 'params'], 'ast/rewriter')
add_lib('bit_blaster', ['rewriter'], 'ast/rewriter/bit_blaster')
add_lib('normal_forms', ['rewriter'], 'ast/normal_forms')
add_lib('substitution', ['rewriter'], 'ast/substitution')
add_lib('proofs', ['rewriter'], 'ast/proofs')
add_lib('macros', ['rewriter'], 'ast/macros')
add_lib('model', ['macros'])
add_lib('converters', ['model'], 'ast/converters')
add_lib('ast_sls', ['ast','normal_forms','converters','smt_params','euf'], 'ast/sls')
add_lib('sat', ['params', 'util', 'dd', 'ast_sls', 'grobner'])
add_lib('nlsat', ['polynomial', 'sat'])
add_lib('lp', ['util', 'nlsat', 'grobner', 'interval', 'smt_params'], 'math/lp')
add_lib('bit_blaster', ['rewriter'], 'ast/rewriter/bit_blaster')
add_lib('substitution', ['rewriter'], 'ast/substitution')
add_lib('proofs', ['rewriter'], 'ast/proofs')
add_lib('simplifiers', ['euf', 'normal_forms', 'bit_blaster', 'converters', 'substitution'], 'ast/simplifiers')
add_lib('ast_sls', ['ast','normal_forms','converters'], 'ast/sls')
add_lib('tactic', ['simplifiers'])
add_lib('mbp', ['model', 'simplex'], 'qe/mbp')
add_lib('qe_lite', ['tactic', 'mbp'], 'qe/lite')

2
src/CMakeLists.txt
View file

@ -54,7 +54,6 @@ add_subdirectory(ast/euf)
add_subdirectory(ast/converters)
add_subdirectory(ast/substitution)
add_subdirectory(ast/simplifiers)
add_subdirectory(ast/sls)
add_subdirectory(tactic)
add_subdirectory(qe/mbp)
add_subdirectory(qe/lite)
@ -74,6 +73,7 @@ add_subdirectory(parsers/smt2)
add_subdirectory(solver/assertions)
add_subdirectory(ast/pattern)
add_subdirectory(math/lp)
add_subdirectory(ast/sls)
add_subdirectory(sat/smt)
add_subdirectory(sat/tactic)
add_subdirectory(nlsat/tactic)

1
src/ast/arith_decl_plugin.h
View file

@ -365,6 +365,7 @@ public:
MATCH_BINARY(is_div0);
MATCH_BINARY(is_idiv0);
MATCH_BINARY(is_power);
MATCH_BINARY(is_power0);
MATCH_UNARY(is_sin);
MATCH_UNARY(is_asin);

2
src/ast/ast.cpp
View file

@ -1714,7 +1714,7 @@ ast * ast_manager::register_node_core(ast * n) {
n->m_id = is_decl(n) ? m_decl_id_gen.mk() : m_expr_id_gen.mk();
// track_id(*this, n, 77);
// track_id(*this, n, 9213);
// TRACE("ast", tout << (s_count++) << " Object " << n->m_id << " was created.\n";);
TRACE("mk_var_bug", tout << "mk_ast: " << n->m_id << "\n";);

4
src/ast/bv_decl_plugin.cpp
View file

@ -932,13 +932,13 @@ unsigned bv_util::get_int2bv_size(parameter const& p) {
return static_cast<unsigned>(sz);
}
app * bv_util::mk_bv2int(expr* e) {
app * bv_util::mk_bv2int(expr* e) const {
sort* s = m_manager.mk_sort(m_manager.mk_family_id("arith"), INT_SORT);
parameter p(s);
return m_manager.mk_app(get_fid(), OP_BV2INT, 1, &p, 1, &e);
}
app* bv_util::mk_int2bv(unsigned sz, expr* e) {
app* bv_util::mk_int2bv(unsigned sz, expr* e) const {
parameter p(sz);
return m_manager.mk_app(get_fid(), OP_INT2BV, 1, &p, 1, &e);
}

4
src/ast/bv_decl_plugin.h
View file

@ -549,8 +549,8 @@ public:
app * mk_bv_ashr(expr* arg1, expr* arg2) { return m_manager.mk_app(get_fid(), OP_BASHR, arg1, arg2); }
app * mk_bv_lshr(expr* arg1, expr* arg2) { return m_manager.mk_app(get_fid(), OP_BLSHR, arg1, arg2); }
app * mk_bv2int(expr* e);
app * mk_int2bv(unsigned sz, expr* e);
app * mk_bv2int(expr* e) const;
app * mk_int2bv(unsigned sz, expr* e) const;
app* mk_bv_rotate_left(expr* arg1, expr* arg2) { return m_manager.mk_app(get_fid(), OP_EXT_ROTATE_LEFT, arg1, arg2); }
app* mk_bv_rotate_right(expr* arg1, expr* arg2) { return m_manager.mk_app(get_fid(), OP_EXT_ROTATE_RIGHT, arg1, arg2); }

2
src/ast/datatype_decl_plugin.h
View file

@ -341,8 +341,10 @@ namespace datatype {
ast_manager & get_manager() const { return m; }
// sort * mk_datatype_sort(symbol const& name, unsigned n, sort* const* params);
bool is_datatype(sort const* s) const { return is_sort_of(s, fid(), DATATYPE_SORT); }
bool is_datatype(expr* e) const { return is_datatype(e->get_sort()); }
bool is_enum_sort(sort* s);
bool is_recursive(sort * ty);
bool is_recursive(expr* e) { return is_recursive(e->get_sort()); }
bool is_recursive_nested(sort * ty);
bool is_constructor(func_decl * f) const { return is_decl_of(f, fid(), OP_DT_CONSTRUCTOR); }
bool is_recognizer(func_decl * f) const { return is_recognizer0(f) || is_is(f); }

17
src/ast/euf/euf_egraph.cpp
View file

@ -82,8 +82,11 @@ namespace euf {
void egraph::reinsert_equality(enode* p) {
SASSERT(p->is_equality());
if (p->value() != l_true && p->get_arg(0)->get_root() == p->get_arg(1)->get_root())
if (p->value() != l_true && p->get_arg(0)->get_root() == p->get_arg(1)->get_root()) {
queue_literal(p, nullptr);
if (p->value() == l_false && !m_on_propagate_literal)
set_conflict(p->get_arg(0), p->get_arg(1), p->m_lit_justification);
}
}
void egraph::queue_literal(enode* p, enode* ante) {
@ -201,6 +204,18 @@ namespace euf {
}
}
void egraph::new_diseq(enode* n, void* reason) {
force_push();
SASSERT(m.is_eq(n->get_expr()));
auto j = justification::external(reason);
auto a = n->get_arg(0), b = n->get_arg(1);
auto r1 = a->get_root(), r2 = b->get_root();
if (r1 == r2)
set_conflict(a, b, j);
else
set_value(n, l_false, j);
}
void egraph::new_diseq(enode* n) {
SASSERT(n->is_equality());
SASSERT(n->value() == l_false);

3
src/ast/euf/euf_egraph.h
View file

@ -278,10 +278,11 @@ namespace euf {
*/
void merge(enode* n1, enode* n2, void* reason) { merge(n1, n2, justification::external(reason)); }
void new_diseq(enode* n);
void new_diseq(enode* n, void* reason);
/**
\brief propagate set of merges.
\brief propagate set of merges.
This call may detect an inconsistency. Then inconsistent() is true.
Use then explain() to extract an explanation for the conflict.

1
src/ast/rewriter/CMakeLists.txt
View file

@ -4,6 +4,7 @@ z3_add_component(rewriter
array_rewriter.cpp
ast_counter.cpp
bit2int.cpp
bv2int_translator.cpp
bool_rewriter.cpp
bv_bounds.cpp
bv_elim.cpp

125
src/ast/rewriter/arith_rewriter.cpp
View file

@ -515,6 +515,129 @@ br_status arith_rewriter::reduce_power(expr * arg1, expr * arg2, op_kind kind, e
}
}
bool arith_rewriter::is_mul_factor(expr* s, expr* t) {
if (m_util.is_mul(t))
return any_of(*to_app(t), [&](expr* m) { return is_mul_factor(s, m); });
return s == t;
}
bool arith_rewriter::is_add_factor(expr* s, expr* t) {
if (m_util.is_add(t))
return all_of(*to_app(t), [&](expr* f) { return is_add_factor(s, f); });
return is_mul_factor(s, t);
}
expr_ref arith_rewriter::remove_factor(expr* s, expr* t) {
if (m_util.is_mul(t)) {
ptr_buffer<expr> r;
r.push_back(t);
for (unsigned i = 0; i < r.size(); ++i) {
expr* arg = r[i];
if (m_util.is_mul(arg)) {
r.append(to_app(arg)->get_num_args(), to_app(arg)->get_args());
r[i] = r.back();
r.pop_back();
--i;
continue;
}
if (s == arg) {
r[i] = r.back();
r.pop_back();
break;
}
}
switch (r.size()) {
case 0:
return expr_ref(m_util.mk_numeral(rational(1), m_util.is_int(t)), m);
case 1:
return expr_ref(r[0], m);
default:
return expr_ref(m_util.mk_mul(r.size(), r.data()), m);
}
}
if (m_util.is_add(t)) {
expr_ref_vector sum(m);
sum.push_back(t);
for (unsigned i = 0; i < sum.size(); ++i) {
expr* arg = sum.get(i);
if (m_util.is_add(arg)) {
sum.append(to_app(arg)->get_num_args(), to_app(arg)->get_args());
sum[i] = sum.back();
sum.pop_back();
--i;
continue;
}
sum[i] = remove_factor(s, arg);
}
if (sum.size() == 1)
return expr_ref(sum.get(0), m);
else
return expr_ref(m_util.mk_add(sum.size(), sum.data()), m);
}
else {
SASSERT(s == t);
return expr_ref(m_util.mk_numeral(rational(1), m_util.is_int(t)), m);
}
}
void arith_rewriter::get_nl_muls(expr* t, ptr_buffer<expr>& muls) {
if (m_util.is_mul(t)) {
for (expr* arg : *to_app(t))
get_nl_muls(arg, muls);
}
else if (!m_util.is_numeral(t))
muls.push_back(t);
}
expr* arith_rewriter::find_nl_factor(expr* t) {
ptr_buffer<expr> sum, muls;
sum.push_back(t);
for (unsigned i = 0; i < sum.size(); ++i) {
expr* arg = sum[i];
if (m_util.is_add(arg))
sum.append(to_app(arg)->get_num_args(), to_app(arg)->get_args());
else if (m_util.is_mul(arg)) {
muls.reset();
get_nl_muls(arg, muls);
if (muls.size() <= 1)
continue;
for (auto m : muls) {
if (is_add_factor(m, t))
return m;
}
return nullptr;
}
}
return nullptr;
}
br_status arith_rewriter::factor_le_ge_eq(expr * arg1, expr * arg2, op_kind kind, expr_ref & result) {
if (is_zero(arg2)) {
expr* f = find_nl_factor(arg1);
if (!f)
return BR_FAILED;
expr_ref f2 = remove_factor(f, arg1);
expr* z = m_util.mk_numeral(rational(0), m_util.is_int(arg1));
result = m.mk_or(m_util.mk_eq(f, z), m_util.mk_eq(f2, z));
switch (kind) {
case EQ:
break;
case GE:
result = m.mk_or(m.mk_iff(m_util.mk_ge(f, z), m_util.mk_ge(f2, z)), result);
break;
case LE:
result = m.mk_or(m.mk_not(m.mk_iff(m_util.mk_ge(f, z), m_util.mk_ge(f2, z))), result);
break;
}
return BR_REWRITE3;
}
return BR_FAILED;
}
br_status arith_rewriter::mk_le_ge_eq_core(expr * arg1, expr * arg2, op_kind kind, expr_ref & result) {
expr *orig_arg1 = arg1, *orig_arg2 = arg2;
expr_ref new_arg1(m);
@ -655,7 +778,7 @@ br_status arith_rewriter::mk_le_ge_eq_core(expr * arg1, expr * arg2, op_kind kin
default: result = m.mk_eq(arg1, arg2); return BR_DONE;
}
}
return BR_FAILED;
return factor_le_ge_eq(arg1, arg2, kind, result);
}

6
src/ast/rewriter/arith_rewriter.h
View file

@ -73,6 +73,12 @@ class arith_rewriter : public poly_rewriter<arith_rewriter_core> {
br_status is_separated(expr * arg1, expr * arg2, op_kind kind, expr_ref & result);
bool is_non_negative(expr* e);
br_status mk_le_ge_eq_core(expr * arg1, expr * arg2, op_kind kind, expr_ref & result);
bool is_add_factor(expr* s, expr* t);
bool is_mul_factor(expr* s, expr* t);
expr* find_nl_factor(expr* t);
void get_nl_muls(expr* t, ptr_buffer<expr>& muls);
expr_ref remove_factor(expr* s, expr* t);
br_status factor_le_ge_eq(expr * arg1, expr * arg2, op_kind kind, expr_ref & result);
bool elim_to_real_var(expr * var, expr_ref & new_var);
bool elim_to_real_mon(expr * monomial, expr_ref & new_monomial);

693
src/ast/rewriter/bv2int_translator.cpp Normal file
View file

@ -0,0 +1,693 @@
/*++
Copyright (c) 2020 Microsoft Corporation
Module Name:
bv2int_translator
Author:
Nikolaj Bjorner (nbjorner) 2024-10-27
--*/
#include "ast/ast.h"
#include "ast/arith_decl_plugin.h"
#include "ast/bv_decl_plugin.h"
#include "ast/rewriter/bv2int_translator.h"
#include "ast/ast_ll_pp.h"
#include "ast/ast_pp.h"
bv2int_translator::bv2int_translator(ast_manager& m, bv2int_translator_trail& ctx) :
m(m),
ctx(ctx),
bv(m),
a(m),
m_translate(m),
m_args(m),
m_pinned(m),
m_vars(m),
m_preds(m)
{}
void bv2int_translator::reset(bool is_plugin) {
m_vars.reset();
m_preds.reset();
for (unsigned i = m_translate.size(); i-- > 0; )
m_translate[i] = nullptr;
m_is_plugin = is_plugin;
}
void bv2int_translator::set_translated(expr* e, expr* r) {
SASSERT(r);
SASSERT(!is_translated(e));
m_translate.setx(e->get_id(), r);
ctx.push_idx(set_vector_idx_trail(m_translate, e->get_id()));
}
void bv2int_translator::internalize_bv(app* e) {
ensure_translated(e);
if (m.is_bool(e)) {
m_preds.push_back(e);
ctx.push(push_back_vector(m_preds));
}
}
void bv2int_translator::ensure_translated(expr* e) {
if (m_translate.get(e->get_id(), nullptr))
return;
ptr_vector<expr> todo;
ast_fast_mark1 visited;
todo.push_back(e);
visited.mark(e);
for (unsigned i = 0; i < todo.size(); ++i) {
expr* e = todo[i];
if (!is_app(e))
continue;
app* a = to_app(e);
if (m.is_bool(e) && a->get_family_id() != bv.get_family_id())
continue;
for (auto arg : *a)
if (!visited.is_marked(arg) && !m_translate.get(arg->get_id(), nullptr)) {
visited.mark(arg);
todo.push_back(arg);
}
}
std::stable_sort(todo.begin(), todo.end(), [&](expr* a, expr* b) { return get_depth(a) < get_depth(b); });
for (expr* e : todo)
translate_expr(e);
}
rational bv2int_translator::bv_size(expr* bv_expr) {
return rational::power_of_two(bv.get_bv_size(bv_expr->get_sort()));
}
void bv2int_translator::translate_expr(expr* e) {
if (is_quantifier(e))
translate_quantifier(to_quantifier(e));
else if (is_var(e))
translate_var(to_var(e));
else {
app* ap = to_app(e);
if (m_is_plugin && ap->get_family_id() == basic_family_id && m.is_bool(ap)) {
set_translated(e, e);
return;
}
m_args.reset();
for (auto arg : *ap)
m_args.push_back(translated(arg));
if (ap->get_family_id() == basic_family_id)
translate_basic(ap);
else if (ap->get_family_id() == bv.get_family_id())
translate_bv(ap);
else
translate_app(ap);
}
}
void bv2int_translator::translate_quantifier(quantifier* q) {
if (m_is_plugin) {
set_translated(q, q);
return;
}
if (is_lambda(q))
throw default_exception("lambdas are not supported in intblaster");
expr* b = q->get_expr();
unsigned nd = q->get_num_decls();
ptr_vector<sort> sorts;
for (unsigned i = 0; i < nd; ++i) {
auto s = q->get_decl_sort(i);
if (bv.is_bv_sort(s)) {
NOT_IMPLEMENTED_YET();
sorts.push_back(a.mk_int());
}
else
sorts.push_back(s);
}
b = translated(b);
// TODO if sorts contain integer, then created bounds variables.
set_translated(q, m.update_quantifier(q, b));
}
void bv2int_translator::translate_var(var* v) {
if (bv.is_bv_sort(v->get_sort()))
set_translated(v, m.mk_var(v->get_idx(), a.mk_int()));
else
set_translated(v, v);
}
// Translate functions that are not built-in or bit-vectors.
// Base method uses fresh functions.
// Other method could use bv2int, int2bv axioms and coercions.
// f(args) = bv2int(f(int2bv(args'))
//
void bv2int_translator::translate_app(app* e) {
if (m_is_plugin && m.is_bool(e)) {
set_translated(e, e);
return;
}
bool has_bv_sort = bv.is_bv(e);
func_decl* f = e->get_decl();
for (unsigned i = 0; i < m_args.size(); ++i)
if (bv.is_bv(e->get_arg(i)))
m_args[i] = bv.mk_int2bv(bv.get_bv_size(e->get_arg(i)), m_args.get(i));
if (has_bv_sort)
m_vars.push_back(e);
if (m_is_plugin) {
expr* r = m.mk_app(f, m_args);
if (has_bv_sort) {
ctx.push(push_back_vector(m_vars));
r = bv.mk_bv2int(r);
}
set_translated(e, r);
return;
}
else if (has_bv_sort) {
if (f->get_family_id() != null_family_id)
throw default_exception("conversion for interpreted functions is not supported by intblast solver");
func_decl* g = nullptr;
if (!m_new_funs.find(f, g)) {
g = m.mk_fresh_func_decl(e->get_decl()->get_name(), symbol("bv"), f->get_arity(), f->get_domain(), a.mk_int());
m_new_funs.insert(f, g);
}
f = g;
m_pinned.push_back(f);
}
set_translated(e, m.mk_app(f, m_args));
}
expr_ref bv2int_translator::mk_le(expr* x, expr* y) {
if (a.is_numeral(y))
return expr_ref(a.mk_le(x, y), m);
if (a.is_numeral(x))
return expr_ref(a.mk_ge(y, x), m);
return expr_ref(a.mk_le(a.mk_sub(x, y), a.mk_numeral(rational(0), x->get_sort())), m);
}
expr_ref bv2int_translator::mk_lt(expr* x, expr* y) {
return expr_ref(m.mk_not(mk_le(y, x)), m);
}
void bv2int_translator::translate_bv(app* e) {
auto bnot = [&](expr* e) {
return a.mk_sub(a.mk_int(-1), e);
};
auto band = [&](expr_ref_vector const& args) {
expr* r = arg(0);
for (unsigned i = 1; i < args.size(); ++i)
r = a.mk_band(bv.get_bv_size(e), r, arg(i));
return r;
};
auto rotate_left = [&](unsigned n) {
auto sz = bv.get_bv_size(e);
n = n % sz;
expr* r = arg(0);
if (n != 0 && sz != 1) {
// r[sz - n - 1 : 0] ++ r[sz - 1 : sz - n]
// r * 2^(sz - n) + (r div 2^n) mod 2^(sz - n)???
// r * A + (r div B) mod A
auto N = bv_size(e);
auto A = rational::power_of_two(sz - n);
auto B = rational::power_of_two(n);
auto hi = mul(r, a.mk_int(A));
auto lo = amod(e, a.mk_idiv(umod(e, 0), a.mk_int(B)), A);
r = add(hi, lo);
}
return r;
};
expr* bv_expr = e;
expr_ref r(m);
auto const& args = m_args;
switch (e->get_decl_kind()) {
case OP_BADD:
r = a.mk_add(args);
break;
case OP_BSUB:
r = a.mk_sub(args.size(), args.data());
break;
case OP_BMUL:
r = a.mk_mul(args);
break;
case OP_ULEQ:
bv_expr = e->get_arg(0);
r = mk_le(umod(bv_expr, 0), umod(bv_expr, 1));
break;
case OP_UGEQ:
bv_expr = e->get_arg(0);
r = mk_ge(umod(bv_expr, 0), umod(bv_expr, 1));
break;
case OP_ULT:
bv_expr = e->get_arg(0);
r = mk_lt(umod(bv_expr, 0), umod(bv_expr, 1));
break;
case OP_UGT:
bv_expr = e->get_arg(0);
r = mk_gt(umod(bv_expr, 0), umod(bv_expr, 1));
break;
case OP_SLEQ:
bv_expr = e->get_arg(0);
r = mk_le(smod(bv_expr, 0), smod(bv_expr, 1));
break;
case OP_SGEQ:
bv_expr = e->get_arg(0);
r = mk_ge(smod(bv_expr, 0), smod(bv_expr, 1));
break;
case OP_SLT:
bv_expr = e->get_arg(0);
r = mk_lt(smod(bv_expr, 0), smod(bv_expr, 1));
break;
case OP_SGT:
bv_expr = e->get_arg(0);
r = mk_gt(smod(bv_expr, 0), smod(bv_expr, 1));
break;
case OP_BNEG:
r = a.mk_uminus(arg(0));
break;
case OP_CONCAT: {
unsigned sz = 0;
expr_ref new_arg(m);
for (unsigned i = args.size(); i-- > 0;) {
expr* old_arg = e->get_arg(i);
new_arg = umod(old_arg, i);
if (sz > 0) {
new_arg = mul(new_arg, a.mk_int(rational::power_of_two(sz)));
r = add(r, new_arg);
}
else
r = new_arg;
sz += bv.get_bv_size(old_arg->get_sort());
}
break;
}
case OP_EXTRACT: {
unsigned lo, hi;
expr* old_arg;
VERIFY(bv.is_extract(e, lo, hi, old_arg));
r = arg(0);
if (lo > 0)
r = a.mk_idiv(r, a.mk_int(rational::power_of_two(lo)));
break;
}
case OP_BV_NUM: {
rational val;
unsigned sz;
VERIFY(bv.is_numeral(e, val, sz));
r = a.mk_int(val);
break;
}
case OP_BUREM:
case OP_BUREM_I: {
expr* x = umod(e, 0), * y = umod(e, 1);
r = if_eq(y, 0, x, a.mk_mod(x, y));
break;
}
case OP_BUDIV:
case OP_BUDIV_I: {
expr* x = umod(e, 0), * y = umod(e, 1);
r = if_eq(y, 0, a.mk_int(-1), a.mk_idiv(x, y));
break;
}
case OP_BUMUL_NO_OVFL: {
bv_expr = e->get_arg(0);
r = mk_lt(mul(umod(bv_expr, 0), umod(bv_expr, 1)), a.mk_int(bv_size(bv_expr)));
break;
}
case OP_BSHL: {
if (!a.is_numeral(arg(0)) && !a.is_numeral(arg(1)))
r = a.mk_shl(bv.get_bv_size(e), arg(0), arg(1));
else {
expr* x = arg(0), * y = umod(e, 1);
r = a.mk_int(0);
for (unsigned i = 0; i < bv.get_bv_size(e); ++i)
r = if_eq(y, i, mul(x, a.mk_int(rational::power_of_two(i))), r);
}
break;
}
case OP_BNOT:
r = bnot(arg(0));
break;
case OP_BLSHR:
if (!a.is_numeral(arg(0)) && !a.is_numeral(arg(1)))
r = a.mk_lshr(bv.get_bv_size(e), arg(0), arg(1));
else {
expr* x = arg(0), * y = umod(e, 1);
r = a.mk_int(0);
IF_VERBOSE(4, verbose_stream() << "lshr " << mk_bounded_pp(e, m) << " " << bv.get_bv_size(e) << "\n");
for (unsigned i = 0; i < bv.get_bv_size(e); ++i)
r = if_eq(y, i, a.mk_idiv(x, a.mk_int(rational::power_of_two(i))), r);
}
break;
case OP_BASHR:
if (!a.is_numeral(arg(1)))
r = a.mk_ashr(bv.get_bv_size(e), arg(0), arg(1));
else {
//
// ashr(x, y)
// if y = k & x >= 0 -> x / 2^k
// if y = k & x < 0 -> (x / 2^k) - 2^{N-k}
//
unsigned sz = bv.get_bv_size(e);
rational N = bv_size(e);
expr* x = umod(e, 0), * y = umod(e, 1);
expr* signx = a.mk_ge(x, a.mk_int(N / 2));
r = m.mk_ite(signx, a.mk_int(-1), a.mk_int(0));
IF_VERBOSE(4, verbose_stream() << "ashr " << mk_bounded_pp(e, m) << " " << bv.get_bv_size(e) << "\n");
for (unsigned i = 0; i < sz; ++i) {
expr* d = a.mk_idiv(x, a.mk_int(rational::power_of_two(i)));
r = if_eq(y, i,
m.mk_ite(signx, add(d, a.mk_int(-rational::power_of_two(sz - i))), d),
r);
}
}
break;
case OP_BOR:
// p | q := (p + q) - band(p, q)
IF_VERBOSE(4, verbose_stream() << "bor " << mk_bounded_pp(e, m) << " " << bv.get_bv_size(e) << "\n");
r = arg(0);
for (unsigned i = 1; i < args.size(); ++i)
r = a.mk_sub(add(r, arg(i)), a.mk_band(bv.get_bv_size(e), r, arg(i)));
break;
case OP_BNAND:
r = bnot(band(args));
break;
case OP_BAND:
IF_VERBOSE(4, verbose_stream() << "band " << mk_bounded_pp(e, m) << " " << bv.get_bv_size(e) << "\n");
r = band(args);
break;
case OP_BXNOR:
case OP_BXOR: {
// p ^ q := (p + q) - 2*band(p, q);
unsigned sz = bv.get_bv_size(e);
IF_VERBOSE(4, verbose_stream() << "bxor " << bv.get_bv_size(e) << "\n");
r = arg(0);
for (unsigned i = 1; i < args.size(); ++i) {
expr* q = arg(i);
r = a.mk_sub(add(r, q), mul(a.mk_int(2), a.mk_band(sz, r, q)));
}
if (e->get_decl_kind() == OP_BXNOR)
r = bnot(r);
break;
}
case OP_ZERO_EXT:
bv_expr = e->get_arg(0);
r = umod(bv_expr, 0);
SASSERT(bv.get_bv_size(e) >= bv.get_bv_size(bv_expr));
break;
case OP_SIGN_EXT: {
bv_expr = e->get_arg(0);
r = umod(bv_expr, 0);
SASSERT(bv.get_bv_size(e) >= bv.get_bv_size(bv_expr));
unsigned arg_sz = bv.get_bv_size(bv_expr);
//unsigned sz = bv.get_bv_size(e);
// rational N = rational::power_of_two(sz);
rational M = rational::power_of_two(arg_sz);
expr* signbit = a.mk_ge(r, a.mk_int(M / 2));
r = m.mk_ite(signbit, a.mk_sub(r, a.mk_int(M)), r);
break;
}
case OP_INT2BV:
m_int2bv.push_back(e);
ctx.push(push_back_vector(m_int2bv));
r = arg(0);
break;
case OP_BV2INT:
m_bv2int.push_back(e);
ctx.push(push_back_vector(m_bv2int));
r = umod(e->get_arg(0), 0);
break;
case OP_BCOMP:
bv_expr = e->get_arg(0);
r = m.mk_ite(m.mk_eq(umod(bv_expr, 0), umod(bv_expr, 1)), a.mk_int(1), a.mk_int(0));
break;
case OP_BSMOD_I:
case OP_BSMOD: {
expr* x = umod(e, 0), * y = umod(e, 1);
rational N = bv_size(e);
expr* signx = a.mk_ge(x, a.mk_int(N / 2));
expr* signy = a.mk_ge(y, a.mk_int(N / 2));
expr* u = a.mk_mod(x, y);
// u = 0 -> 0
// y = 0 -> x
// x < 0, y < 0 -> -u
// x < 0, y >= 0 -> y - u
// x >= 0, y < 0 -> y + u
// x >= 0, y >= 0 -> u
r = a.mk_uminus(u);
r = m.mk_ite(m.mk_and(m.mk_not(signx), signy), add(u, y), r);
r = m.mk_ite(m.mk_and(signx, m.mk_not(signy)), a.mk_sub(y, u), r);
r = m.mk_ite(m.mk_and(m.mk_not(signx), m.mk_not(signy)), u, r);
r = if_eq(u, 0, a.mk_int(0), r);
r = if_eq(y, 0, x, r);
break;
}
case OP_BSDIV_I:
case OP_BSDIV: {
// d = udiv(abs(x), abs(y))
// y = 0, x > 0 -> 1
// y = 0, x <= 0 -> -1
// x = 0, y != 0 -> 0
// x > 0, y < 0 -> -d
// x < 0, y > 0 -> -d
// x > 0, y > 0 -> d
// x < 0, y < 0 -> d
expr* x = umod(e, 0), * y = umod(e, 1);
rational N = bv_size(e);
expr* signx = a.mk_ge(x, a.mk_int(N / 2));
expr* signy = a.mk_ge(y, a.mk_int(N / 2));
x = m.mk_ite(signx, a.mk_sub(a.mk_int(N), x), x);
y = m.mk_ite(signy, a.mk_sub(a.mk_int(N), y), y);
expr* d = a.mk_idiv(x, y);
r = m.mk_ite(m.mk_iff(signx, signy), d, a.mk_uminus(d));
r = if_eq(y, 0, m.mk_ite(signx, a.mk_int(1), a.mk_int(-1)), r);
break;
}
case OP_BSREM_I:
case OP_BSREM: {
// y = 0 -> x
// else x - sdiv(x, y) * y
expr* x = umod(e, 0), * y = umod(e, 1);
rational N = bv_size(e);
expr* signx = a.mk_ge(x, a.mk_int(N / 2));
expr* signy = a.mk_ge(y, a.mk_int(N / 2));
expr* absx = m.mk_ite(signx, a.mk_sub(a.mk_int(N), x), x);
expr* absy = m.mk_ite(signy, a.mk_sub(a.mk_int(N), y), y);
expr* d = a.mk_idiv(absx, absy);
d = m.mk_ite(m.mk_iff(signx, signy), d, a.mk_uminus(d));
r = a.mk_sub(x, mul(d, y));
r = if_eq(y, 0, x, r);
break;
}
case OP_ROTATE_LEFT: {
auto n = e->get_parameter(0).get_int();
r = rotate_left(n);
break;
}
case OP_ROTATE_RIGHT: {
unsigned sz = bv.get_bv_size(e);
auto n = e->get_parameter(0).get_int();
r = rotate_left(sz - n);
break;
}
case OP_EXT_ROTATE_LEFT: {
unsigned sz = bv.get_bv_size(e);
expr* y = umod(e, 1);
r = a.mk_int(0);
for (unsigned i = 0; i < sz; ++i)
r = if_eq(y, i, rotate_left(i), r);
break;
}
case OP_EXT_ROTATE_RIGHT: {
unsigned sz = bv.get_bv_size(e);
expr* y = umod(e, 1);
r = a.mk_int(0);
for (unsigned i = 0; i < sz; ++i)
r = if_eq(y, i, rotate_left(sz - i), r);
break;
}
case OP_REPEAT: {
unsigned n = e->get_parameter(0).get_int();
expr* x = umod(e->get_arg(0), 0);
r = x;
rational N = bv_size(e->get_arg(0));
rational N0 = N;
for (unsigned i = 1; i < n; ++i)
r = add(mul(a.mk_int(N), x), r), N *= N0;
break;
}
case OP_BREDOR: {
r = umod(e->get_arg(0), 0);
r = m.mk_not(m.mk_eq(r, a.mk_int(0)));
break;
}
case OP_BREDAND: {
rational N = bv_size(e->get_arg(0));
r = umod(e->get_arg(0), 0);
r = m.mk_not(m.mk_eq(r, a.mk_int(N - 1)));
break;
}
default:
verbose_stream() << mk_pp(e, m) << "\n";
NOT_IMPLEMENTED_YET();
}
set_translated(e, r);
}
expr_ref bv2int_translator::if_eq(expr* n, unsigned k, expr* th, expr* el) {
rational r;
expr_ref _th(th, m), _el(el, m);
if (bv.is_numeral(n, r)) {
if (r == k)
return expr_ref(th, m);
else
return expr_ref(el, m);
}
return expr_ref(m.mk_ite(m.mk_eq(n, a.mk_int(k)), th, el), m);
}
void bv2int_translator::translate_basic(app* e) {
if (m.is_eq(e)) {
bool has_bv_arg = any_of(*e, [&](expr* arg) { return bv.is_bv(arg); });
if (has_bv_arg) {
expr* bv_expr = e->get_arg(0);
rational N = rational::power_of_two(bv.get_bv_size(bv_expr));
if (a.is_numeral(arg(0)) || a.is_numeral(arg(1)) ||
is_bounded(arg(0), N) || is_bounded(arg(1), N)) {
set_translated(e, m.mk_eq(umod(bv_expr, 0), umod(bv_expr, 1)));
}
else {
m_args[0] = a.mk_sub(arg(0), arg(1));
set_translated(e, m.mk_eq(umod(bv_expr, 0), a.mk_int(0)));
}
}
else
set_translated(e, m.mk_eq(arg(0), arg(1)));
}
else if (m.is_ite(e))
set_translated(e, m.mk_ite(arg(0), arg(1), arg(2)));
else if (m_is_plugin)
set_translated(e, e);
else
set_translated(e, m.mk_app(e->get_decl(), m_args));
}
bool bv2int_translator::is_bounded(expr* x, rational const& N) {
return any_of(m_vars, [&](expr* v) {
return is_translated(v) && translated(v) == x && bv_size(v) <= N;
});
}
bool bv2int_translator::is_non_negative(expr* bv_expr, expr* e) {
auto N = rational::power_of_two(bv.get_bv_size(bv_expr));
rational r;
if (a.is_numeral(e, r))
return r >= 0;
if (is_bounded(e, N))
return true;
expr* x = nullptr, * y = nullptr;
if (a.is_mul(e, x, y))
return is_non_negative(bv_expr, x) && is_non_negative(bv_expr, y);
if (a.is_add(e, x, y))
return is_non_negative(bv_expr, x) && is_non_negative(bv_expr, y);
return false;
}
expr* bv2int_translator::umod(expr* bv_expr, unsigned i) {
expr* x = arg(i);
rational N = bv_size(bv_expr);
return amod(bv_expr, x, N);
}
expr* bv2int_translator::smod(expr* bv_expr, unsigned i) {
expr* x = arg(i);
auto N = bv_size(bv_expr);
auto shift = N / 2;
rational r;
if (a.is_numeral(x, r))
return a.mk_int(mod(r + shift, N));
return amod(bv_expr, add(x, a.mk_int(shift)), N);
}
expr_ref bv2int_translator::mul(expr* x, expr* y) {
expr_ref _x(x, m), _y(y, m);
if (a.is_zero(x))
return _x;
if (a.is_zero(y))
return _y;
if (a.is_one(x))
return _y;
if (a.is_one(y))
return _x;
rational v1, v2;
if (a.is_numeral(x, v1) && a.is_numeral(y, v2))
return expr_ref(a.mk_int(v1 * v2), m);
_x = a.mk_mul(x, y);
return _x;
}
expr_ref bv2int_translator::add(expr* x, expr* y) {
expr_ref _x(x, m), _y(y, m);
if (a.is_zero(x))
return _y;
if (a.is_zero(y))
return _x;
rational v1, v2;
if (a.is_numeral(x, v1) && a.is_numeral(y, v2))
return expr_ref(a.mk_int(v1 + v2), m);
_x = a.mk_add(x, y);
return _x;
}
/*
* Perform simplifications that are claimed sound when the bit-vector interpretations of
* mod/div always guard the mod and dividend to be non-zero.
* Potentially shady area is for arithmetic expressions created by int2bv.
* They will be guarded by a modulus which does not disappear.
*/
expr* bv2int_translator::amod(expr* bv_expr, expr* x, rational const& N) {
rational v;
expr* r = nullptr, * c = nullptr, * t = nullptr, * e = nullptr;
if (m.is_ite(x, c, t, e))
r = m.mk_ite(c, amod(bv_expr, t, N), amod(bv_expr, e, N));
else if (a.is_idiv(x, t, e) && a.is_numeral(t, v) && 0 <= v && v < N && is_non_negative(bv_expr, e))
r = x;
else if (a.is_mod(x, t, e) && a.is_numeral(t, v) && 0 <= v && v < N)
r = x;
else if (a.is_numeral(x, v))
r = a.mk_int(mod(v, N));
else if (is_bounded(x, N))
r = x;
else
r = a.mk_mod(x, a.mk_int(N));
return r;
}
void bv2int_translator::translate_eq(expr* e) {
expr* x = nullptr, * y = nullptr;
VERIFY(m.is_eq(e, x, y));
SASSERT(bv.is_bv(x));
if (!is_translated(e)) {
ensure_translated(x);
ensure_translated(y);
m_args.reset();
m_args.push_back(a.mk_sub(translated(x), translated(y)));
set_translated(e, m.mk_eq(umod(x, 0), a.mk_int(0)));
}
m_preds.push_back(e);
TRACE("bv", tout << mk_pp(e, m) << " " << mk_pp(translated(e), m) << "\n");
ctx.push(push_back_vector(m_preds));
}

84
src/ast/rewriter/bv2int_translator.h Normal file
View file

@ -0,0 +1,84 @@
/*++
Copyright (c) 2020 Microsoft Corporation
Module Name:
bv2int_translator
Utilities for translating bit-vector constraints into arithmetic.
Author:
Nikolaj Bjorner (nbjorner) 2024-10-27
--*/
#pragma once
#include "util/trail.h"
class bv2int_translator_trail {
public:
virtual ~bv2int_translator_trail() {}
virtual void push(push_back_vector<expr_ref_vector> const& c) = 0;
virtual void push(push_back_vector<ptr_vector<app>> const& c) = 0;
virtual void push_idx(set_vector_idx_trail<expr_ref_vector> const& c) = 0;
};
class bv2int_translator {
ast_manager& m;
bv2int_translator_trail& ctx;
bv_util bv;
arith_util a;
obj_map<func_decl, func_decl*> m_new_funs;
expr_ref_vector m_translate, m_args;
ast_ref_vector m_pinned;
ptr_vector<app> m_bv2int, m_int2bv;
expr_ref_vector m_vars, m_preds;
bool m_is_plugin = true;
void set_translated(expr* e, expr* r);
expr* arg(unsigned i) { return m_args.get(i); }
expr* umod(expr* bv_expr, unsigned i);
expr* smod(expr* bv_expr, unsigned i);
bool is_bounded(expr* v, rational const& N);
bool is_non_negative(expr* bv_expr, expr* e);
expr_ref mul(expr* x, expr* y);
expr_ref add(expr* x, expr* y);
expr_ref if_eq(expr* n, unsigned k, expr* th, expr* el);
expr* amod(expr* bv_expr, expr* x, rational const& N);
rational bv_size(expr* bv_expr);
expr_ref mk_le(expr* a, expr* b);
expr_ref mk_lt(expr* a, expr* b);
expr_ref mk_ge(expr* a, expr* b) { return mk_le(b, a); }
expr_ref mk_gt(expr* a, expr* b) { return mk_lt(b, a); }
void translate_bv(app* e);
void translate_basic(app* e);
void translate_app(app* e);
void translate_quantifier(quantifier* q);
void translate_var(var* v);
public:
bv2int_translator(ast_manager& m, bv2int_translator_trail& ctx);
void ensure_translated(expr* e);
void translate_eq(expr* e);
bool is_translated(expr* e) const { return !!m_translate.get(e->get_id(), nullptr); }
expr* translated(expr* e) const { expr* r = m_translate.get(e->get_id(), nullptr); SASSERT(r); return r; }
void internalize_bv(app* e);
void translate_expr(expr* e);
expr_ref_vector const& vars() const { return m_vars; }
expr_ref_vector const& preds() const { return m_preds; }
ptr_vector<app> const& bv2int() const { return m_bv2int; }
ptr_vector<app> const& int2bv() const { return m_int2bv; }
void reset(bool is_plugin);
};

10
src/ast/rewriter/bv_rewriter.h
View file

@ -223,7 +223,7 @@ public:
#define MK_BV_BINARY(OP) \
expr_ref OP(expr* a, expr* b) { \
expr_ref result(m); \
expr_ref result(m), _a(a, m), _b(b, m); \
if (BR_FAILED == OP(a, b, result)) \
result = m_util.OP(a, b); \
return result; \
@ -238,6 +238,7 @@ public:
MK_BV_BINARY(mk_bv_urem);
MK_BV_BINARY(mk_ule);
MK_BV_BINARY(mk_sle);
MK_BV_BINARY(mk_bv_add);
MK_BV_BINARY(mk_bv_mul);
MK_BV_BINARY(mk_bv_sub);
@ -250,6 +251,13 @@ public:
return result;
}
expr_ref mk_bv_neg(expr* a) {
expr_ref result(a, m);
if (BR_FAILED == mk_uminus(a, result))
result = m_util.mk_bv_neg(a);
return result;
}
};

419
src/ast/simplifiers/elim_unconstrained.cpp
View file

@ -42,6 +42,73 @@ proof production is work in progress.
reconstruct_term should assign proof objects with nodes by applying
monotonicity or reflexivity rules.
Maintain term nodes.
Each term node has a root. The root of the root is itself.
The root of a term node can be updated.
The parents of terms with same roots are combined.
The depth of a parent is always greater than the depth of a child.
The effective term of a node is reconstructed by taking the root and canonizing the children based on roots.
The reference count of a term is the number of parents it has.
node: term -> node
dirty: node -> bool
root: node -> node
top: node -> bool
term: node -> term
invariant:
- root(root(n)) = root(n)
- term(node(t)) = t
parents: node -> node*
parents(root(node)) = union of parents of n : root(n) = root(node).
is_child(n, p) = term(root(n)) in args(term(root(p)))
set_root: node -> node -> void
set_root(n, r) =
r = root(r)
n = root(n)
if r = n then return
parents(r) = parents(r) union parents(n)
root(n) := r,
top(r) := top(r) or top(n)
set all parents of class(r) to dirty, recursively
reconstruct_term: node -> term
reconstruct_term(n) =
r = root(n)
if dirty(r) then
args = [reconstruct_term(c) | c in args(term(r))]
term(r) := term(r).f(args)
dirty(r) := false
return term(r)
live : term -> bool
live(t) =
n = node(t)
is_root(n) & (top(n) or p in parents(n) : live(p))
Only live nodes require updates.
eliminate:
while heap is not empty:
v = heap.erase_min()
n = node(v)
if n.parents.size() > 1 then
return
if !is_root(n) or !live(n) or n.parents.size() != 1 then
continue
p = n.parents[0]
if !is_child(n, p) or !is_root(p) then
continue
t = p.term
args = [reconstruct_term(node(arg)) | arg in t]
r = inverter(t.f, args)
if r then
set_root(n, r)
--*/
@ -54,15 +121,17 @@ monotonicity or reflexivity rules.
elim_unconstrained::elim_unconstrained(ast_manager& m, dependent_expr_state& fmls) :
dependent_expr_simplifier(m, fmls), m_inverter(m), m_lt(*this), m_heap(1024, m_lt), m_trail(m), m_args(m) {
std::function<bool(expr*)> is_var = [&](expr* e) {
return is_uninterp_const(e) && !m_fmls.frozen(e) && is_node(e) && get_node(e).m_refcount <= 1;
return is_uninterp_const(e) && !m_fmls.frozen(e) && get_node(e).is_root() && get_node(e).num_parents() <= 1;
};
m_inverter.set_is_var(is_var);
}
bool elim_unconstrained::is_var_lt(int v1, int v2) const {
node const& n1 = get_node(v1);
node const& n2 = get_node(v2);
return n1.m_refcount < n2.m_refcount;
elim_unconstrained::~elim_unconstrained() {
reset_nodes();
}
bool elim_unconstrained::is_var_lt(int v1, int v2) const {
return get_node(v1).num_parents() < get_node(v2).num_parents();
}
void elim_unconstrained::eliminate() {
@ -70,30 +139,29 @@ void elim_unconstrained::eliminate() {
expr_ref r(m);
int v = m_heap.erase_min();
node& n = get_node(v);
if (n.m_refcount == 0)
if (!n.is_root() || n.is_top())
continue;
if (n.m_refcount > 1)
unsigned num_parents = n.num_parents();
if (num_parents == 0)
continue;
if (num_parents > 1)
return;
if (n.m_parents.empty()) {
n.m_refcount = 0;
node& p = n.parent();
if (!is_child(n, p) || !p.is_root())
continue;
}
expr* e = get_parent(v);
TRACE("elim_unconstrained", for (expr* p : n.m_parents) tout << "parent " << mk_bounded_pp(p, m) << " @ " << get_node(p).m_refcount << "\n";);
if (!e || !is_app(e) || !is_ground(e)) {
n.m_refcount = 0;
expr* e = p.term();
if (!e || !is_app(e) || !is_ground(e))
continue;
}
if (m_heap.contains(root(e))) {
TRACE("elim_unconstrained", tout << "already in heap " << mk_bounded_pp(e, m) << "\n");
continue;
}
SASSERT(!m_heap.contains(p.term()->get_id()));
app* t = to_app(e);
TRACE("elim_unconstrained", tout << "eliminating " << mk_pp(t, m) << "\n";);
TRACE("elim_unconstrained", tout << "eliminating " << mk_bounded_pp(t, m) << "\n";);
unsigned sz = m_args.size();
for (expr* arg : *to_app(t))
m_args.push_back(reconstruct_term(get_node(arg)));
m_args.push_back(reconstruct_term(root(arg)));
expr_ref rr(m.mk_app(t->get_decl(), t->get_num_args(), m_args.data() + sz), m);
bool inverted = m_inverter(t->get_decl(), t->get_num_args(), m_args.data() + sz, r);
proof_ref pr(m);
if (inverted && m_enable_proofs) {
@ -103,67 +171,91 @@ void elim_unconstrained::eliminate() {
proof * pr = m.mk_apply_def(s, r, pr1);
m_trail.push_back(pr);
}
expr_ref rr(m.mk_app(t->get_decl(), t->get_num_args(), m_args.data() + sz), m);
n.m_refcount = 0;
m_args.shrink(sz);
if (!inverted) {
TRACE("elim_unconstrained", tout << "not inverted " << mk_bounded_pp(e, m) << "\n");
if (!inverted)
continue;
}
IF_VERBOSE(11, verbose_stream() << "replace " << mk_pp(t, m) << " / " << rr << " -> " << r << "\n");
IF_VERBOSE(4, verbose_stream() << "replace " << mk_bounded_pp(t, m) << " / " << mk_bounded_pp(rr, m) << " -> " << mk_bounded_pp(r, m) << "\n");
TRACE("elim_unconstrained", tout << mk_pp(t, m) << " / " << rr << " -> " << r << "\n");
TRACE("elim_unconstrained", tout << mk_bounded_pp(t, m) << " / " << mk_bounded_pp(rr, m) << " -> " << mk_bounded_pp(r, m) << "\n");
SASSERT(r->get_sort() == t->get_sort());
m_stats.m_num_eliminated++;
m_trail.push_back(r);
SASSERT(r);
gc(e);
invalidate_parents(e);
freeze_rec(r);
m_root.setx(r->get_id(), e->get_id(), UINT_MAX);
get_node(e).m_term = r;
get_node(e).m_proof = pr;
get_node(e).m_refcount++;
get_node(e).m_dirty = false;
IF_VERBOSE(11, verbose_stream() << "set " << &get_node(e) << " " << root(e) << " " << mk_bounded_pp(e, m) << " := " << mk_bounded_pp(r, m) << "\n");
SASSERT(!m_heap.contains(root(e)));
if (is_uninterp_const(r))
m_heap.insert(root(e));
node& rn = root(r);
set_root(p, rn);
expr* rt = rn.term();
SASSERT(!m_heap.contains(rt->get_id()));
if (is_uninterp_const(rt))
m_heap.insert(rt->get_id());
else
m_created_compound = true;
IF_VERBOSE(11, verbose_stream() << mk_bounded_pp(get_node(v).m_orig, m) << " " << mk_bounded_pp(t, m) << " -> " << r << " " << get_node(e).m_refcount << "\n";);
}
}
expr* elim_unconstrained::get_parent(unsigned n) const {
for (expr* p : get_node(n).m_parents)
if (get_node(p).m_refcount > 0 && get_node(p).m_term == get_node(p).m_orig)
return p;
return nullptr;
void elim_unconstrained::set_root(node& n, node& r) {
SASSERT(n.is_root());
SASSERT(r.is_root());
if (&n == &r)
return;
r.add_parents(n.parents());
n.set_root(r);
for (auto p : n.parents())
invalidate_parents(*p);
}
void elim_unconstrained::invalidate_parents(expr* e) {
ptr_buffer<expr> todo;
void elim_unconstrained::invalidate_parents(node& n) {
ptr_buffer<node> todo;
node* np = &n;
do {
node& n = get_node(e);
if (!n.m_dirty && e == n.m_term) {
n.m_dirty = true;
for (expr* e : n.m_parents)
todo.push_back(e);
node& n = *np;
if (!n.is_dirty()) {
n.set_dirty();
for (auto* p : n.parents())
todo.push_back(p);
}
e = nullptr;
np = nullptr;
if (!todo.empty()) {
e = todo.back();
np = todo.back();
todo.pop_back();
}
}
while (e);
while (np);
}
bool elim_unconstrained::is_child(node const& ch, node const& p) {
SASSERT(ch.is_root());
return is_app(p.term()) && any_of(*to_app(p.term()), [&](expr* arg) { return &root(arg) == &ch; });
}
elim_unconstrained::node& elim_unconstrained::get_node(expr* t) {
unsigned id = t->get_id();
if (m_nodes.size() <= id)
m_nodes.resize(id + 1, nullptr);
node* n = m_nodes[id];
if (!n) {
n = alloc(node, m, t);
m_nodes[id] = n;
if (is_app(t)) {
for (auto arg : *to_app(t)) {
node& ch = get_node(arg);
SASSERT(ch.is_root());
ch.add_parent(*n);
}
}
else if (is_quantifier(t)) {
node& ch = get_node(to_quantifier(t)->get_expr());
SASSERT(ch.is_root());
ch.add_parent(*n);
}
}
return *n;
}
void elim_unconstrained::reset_nodes() {
for (node* n : m_nodes)
dealloc(n);
m_nodes.reset();
}
/**
* initialize node structure
@ -182,201 +274,95 @@ void elim_unconstrained::init_nodes() {
m_enable_proofs = true;
}
m_trail.append(terms);
m_heap.reset();
m_root.reset();
m_nodes.reset();
reset_nodes();
// initialize nodes for terms in the original goal
init_terms(terms);
// top-level terms have reference count > 0
for (expr* e : terms)
inc_ref(e);
m_inverter.set_produce_proofs(m_enable_proofs);
}
/**
* Create nodes for all terms in the goal
*/
void elim_unconstrained::init_terms(expr_ref_vector const& terms) {
unsigned max_id = 0;
for (expr* e : subterms::all(terms))
max_id = std::max(max_id, e->get_id());
m_nodes.reserve(max_id + 1);
m_heap.reserve(max_id + 1);
m_root.reserve(max_id + 1, UINT_MAX);
for (expr* e : subterms_postorder::all(terms)) {
m_root.setx(e->get_id(), e->get_id(), UINT_MAX);
node& n = get_node(e);
if (n.m_term)
continue;
n.m_orig = e;
n.m_term = e;
n.m_refcount = 0;
SASSERT(n.is_root());
if (is_uninterp_const(e))
m_heap.insert(root(e));
if (is_quantifier(e)) {
expr* body = to_quantifier(e)->get_expr();
get_node(body).m_parents.push_back(e);
inc_ref(body);
}
else if (is_app(e)) {
for (expr* arg : *to_app(e)) {
get_node(arg).m_parents.push_back(e);
inc_ref(arg);
}
}
m_heap.insert(e->get_id());
}
}
void elim_unconstrained::freeze_rec(expr* r) {
expr_ref_vector children(m);
if (is_quantifier(r))
children.push_back(to_quantifier(r)->get_expr());
else if (is_app(r))
children.append(to_app(r)->get_num_args(), to_app(r)->get_args());
else
return;
if (children.empty())
return;
for (expr* t : subterms::all(children))
freeze(t);
}
// mark top level terms
for (expr* e : terms)
get_node(e).set_top();
void elim_unconstrained::freeze(expr* t) {
if (!is_uninterp_const(t))
return;
if (m_nodes.size() <= t->get_id())
return;
if (m_nodes.size() <= root(t))
return;
node& n = get_node(t);
if (!n.m_term)
return;
if (m_heap.contains(root(t))) {
n.m_refcount = UINT_MAX / 2;
m_heap.increased(root(t));
}
}
void elim_unconstrained::gc(expr* t) {
ptr_vector<expr> todo;
todo.push_back(t);
while (!todo.empty()) {
t = todo.back();
todo.pop_back();
m_inverter.set_produce_proofs(m_enable_proofs);
node& n = get_node(t);
if (n.m_refcount == 0)
continue;
if (n.m_term && !is_node(n.m_term))
continue;
dec_ref(t);
if (n.m_refcount != 0)
continue;
if (n.m_term)
t = n.m_term;
if (is_app(t)) {
for (expr* arg : *to_app(t))
todo.push_back(arg);
}
else if (is_quantifier(t))
todo.push_back(to_quantifier(t)->get_expr());
}
}
expr_ref elim_unconstrained::reconstruct_term(node& n0) {
expr* t = n0.m_term;
if (!n0.m_dirty)
return expr_ref(t, m);
if (!is_node(t))
return expr_ref(t, m);
ptr_buffer<expr> todo;
todo.push_back(t);
expr* elim_unconstrained::reconstruct_term(node& n) {
SASSERT(n.is_root());
if (!n.is_dirty())
return n.term();
ptr_buffer<node> todo;
todo.push_back(&n);
expr_ref new_t(m);
while (!todo.empty()) {
t = todo.back();
if (!is_node(t)) {
UNREACHABLE();
node* np = todo.back();
if (!np->is_dirty()) {
todo.pop_back();
continue;
}
node& n = get_node(t);
SASSERT(np->is_root());
auto t = np->term();
unsigned sz0 = todo.size();
if (is_app(t)) {
if (n.m_term != t) {
n.m_dirty = false;
todo.pop_back();
continue;
if (is_app(t)) {
for (expr* arg : *to_app(t)) {
node& r = root(arg);
if (r.is_dirty())
todo.push_back(&r);
}
for (expr* arg : *to_app(t))
if (get_node(arg).m_dirty || !get_node(arg).m_term)
todo.push_back(arg);
if (todo.size() != sz0)
continue;
unsigned sz = m_args.size();
for (expr* arg : *to_app(t))
m_args.push_back(get_node(arg).m_term);
n.m_term = m.mk_app(to_app(t)->get_decl(), to_app(t)->get_num_args(), m_args.data() + sz);
for (expr* arg : *to_app(t))
m_args.push_back(root(arg).term());
new_t = m.mk_app(to_app(t)->get_decl(), to_app(t)->get_num_args(), m_args.data() + sz);
m_args.shrink(sz);
}
else if (is_quantifier(t)) {
expr* body = to_quantifier(t)->get_expr();
node& n2 = get_node(body);
if (n2.m_dirty || !n2.m_term) {
todo.push_back(body);
node& n2 = root(body);
if (n2.is_dirty()) {
todo.push_back(&n2);
continue;
}
n.m_term = m.update_quantifier(to_quantifier(t), n2.m_term);
new_t = m.update_quantifier(to_quantifier(t), n2.term());
}
m_trail.push_back(n.m_term);
m_root.setx(n.m_term->get_id(), n.m_term->get_id(), UINT_MAX);
else
new_t = t;
node& new_n = get_node(new_t);
set_root(*np, new_n);
np->set_clean();
todo.pop_back();
n.m_dirty = false;
}
return expr_ref(n0.m_term, m);
return n.root().term();
}
/**
* walk nodes starting from lowest depth and reconstruct their normalized forms.
*/
void elim_unconstrained::reconstruct_terms() {
expr_ref_vector terms(m);
for (unsigned i : indices())
terms.push_back(m_fmls[i].fml());
ptr_vector<node> nodes;
for (node* n : m_nodes)
if (n && n->is_root())
nodes.push_back(n);
for (expr* e : subterms_postorder::all(terms)) {
node& n = get_node(e);
expr* t = n.m_term;
if (t != n.m_orig)
continue;
if (is_app(t)) {
bool change = false;
m_args.reset();
for (expr* arg : *to_app(t)) {
node& n2 = get_node(arg);
m_args.push_back(n2.m_term);
change |= n2.m_term != n2.m_orig;
}
if (change) {
n.m_term = m.mk_app(to_app(t)->get_decl(), m_args);
m_trail.push_back(n.m_term);
}
}
else if (is_quantifier(t)) {
node& n2 = get_node(to_quantifier(t)->get_expr());
if (n2.m_term != n2.m_orig) {
n.m_term = m.update_quantifier(to_quantifier(t), n2.m_term);
m_trail.push_back(n.m_term);
}
}
}
std::stable_sort(nodes.begin(), nodes.end(), [&](node* a, node* b) { return get_depth(a->term()) < get_depth(b->term()); });
for (node* n : nodes)
reconstruct_term(*n);
}
@ -384,12 +370,11 @@ void elim_unconstrained::assert_normalized(vector<dependent_expr>& old_fmls) {
for (unsigned i : indices()) {
auto [f, p, d] = m_fmls[i]();
node& n = get_node(f);
expr* g = n.m_term;
node& n = root(f);
expr* g = n.term();
if (f == g)
continue;
old_fmls.push_back(m_fmls[i]);
IF_VERBOSE(11, verbose_stream() << mk_bounded_pp(f, m, 3) << " -> " << mk_bounded_pp(g, m, 3) << "\n");
TRACE("elim_unconstrained", tout << mk_bounded_pp(f, m) << " -> " << mk_bounded_pp(g, m) << "\n");
m_fmls.update(i, dependent_expr(m, g, nullptr, d));
}
@ -441,6 +426,6 @@ void elim_unconstrained::reduce() {
vector<dependent_expr> old_fmls;
assert_normalized(old_fmls);
update_model_trail(*mc, old_fmls);
mc->reset();
mc->reset();
}
}

83
src/ast/simplifiers/elim_unconstrained.h
View file

@ -24,14 +24,49 @@ class elim_unconstrained : public dependent_expr_simplifier {
friend class seq_simplifier;
struct node {
unsigned m_refcount = 0;
expr* m_term = nullptr;
expr* m_orig = nullptr;
proof* m_proof = nullptr;
class node {
expr_ref m_term;
proof_ref m_proof;
bool m_dirty = false;
ptr_vector<expr> m_parents;
ptr_vector<node> m_parents;
node* m_root = nullptr;
bool m_top = false;
public:
node(ast_manager& m, expr* t) :
m_term(t, m),
m_proof(m),
m_root(this) {
}
void set_top() { m_top = true; }
bool is_top() const { return m_top; }
void set_dirty() { m_dirty = true; }
void set_clean() { m_dirty = false; }
bool is_dirty() const { return m_dirty; }
unsigned num_parents() const { return m_parents.size(); }
ptr_vector<node> const& parents() const { return m_parents; }
void add_parent(node& p) { m_parents.push_back(&p); }
void add_parents(ptr_vector<node> const& ps) { m_parents.append(ps); }
node& parent() const { SASSERT(num_parents() == 1); return *m_parents[0]; }
bool is_root() const { return m_root == this; }
node& root() { node* r = m_root; while (!r->is_root()) r = r->m_root; return *r; }
node const& root() const { node* r = m_root; while (!r->is_root()) r = r->m_root; return *r; }
void set_root(node& r) {
SASSERT(r.is_root());
m_root = &r;
SASSERT(term()->get_sort() == r.term()->get_sort());
}
void set_proof(proof* p) { m_proof = p; }
proof* get_proof() const { return m_proof; }
expr* term() const { return m_term; }
};
struct var_lt {
elim_unconstrained& s;
var_lt(elim_unconstrained& s) : s(s) {}
@ -39,50 +74,44 @@ class elim_unconstrained : public dependent_expr_simplifier {
return s.is_var_lt(v1, v2);
}
};
struct stats {
unsigned m_num_eliminated = 0;
void reset() { m_num_eliminated = 0; }
};
expr_inverter m_inverter;
vector<node> m_nodes;
ptr_vector<node> m_nodes;
var_lt m_lt;
heap<var_lt> m_heap;
expr_ref_vector m_trail;
expr_ref_vector m_args;
stats m_stats;
unsigned_vector m_root;
bool m_created_compound = false;
bool m_enable_proofs = false;
bool is_var_lt(int v1, int v2) const;
bool is_node(unsigned n) const { return m_nodes.size() > n; }
bool is_node(expr* t) const { return is_node(t->get_id()); }
node& get_node(unsigned n) { return m_nodes[n]; }
node const& get_node(unsigned n) const { return m_nodes[n]; }
node& get_node(expr* t) { return m_nodes[root(t)]; }
unsigned root(expr* t) const { return m_root[t->get_id()]; }
node const& get_node(expr* t) const { return m_nodes[root(t)]; }
unsigned get_refcount(expr* t) const { return get_node(t).m_refcount; }
void inc_ref(expr* t) { ++get_node(t).m_refcount; if (is_uninterp_const(t)) m_heap.increased(root(t)); }
void dec_ref(expr* t) { --get_node(t).m_refcount; if (is_uninterp_const(t)) m_heap.decreased(root(t)); }
void freeze(expr* t);
void freeze_rec(expr* r);
void gc(expr* t);
expr* get_parent(unsigned n) const;
void init_terms(expr_ref_vector const& terms);
node& get_node(unsigned n) const { return *m_nodes[n]; }
node& get_node(expr* t);
node& root(expr* t) { return get_node(t).root(); }
void set_root(node& n, node& r);
void invalidate_parents(node& n);
bool is_child(node const& ch, node const& p);
void init_nodes();
void reset_nodes();
void eliminate();
void reconstruct_terms();
expr_ref reconstruct_term(node& n);
expr* reconstruct_term(node& n);
void assert_normalized(vector<dependent_expr>& old_fmls);
void update_model_trail(generic_model_converter& mc, vector<dependent_expr> const& old_fmls);
void invalidate_parents(expr* e);
public:
elim_unconstrained(ast_manager& m, dependent_expr_state& fmls);
~elim_unconstrained() override;
char const* name() const override { return "elim-unconstrained"; }
void reduce() override;

23
src/ast/sls/CMakeLists.txt
View file

@ -1,14 +1,25 @@
z3_add_component(ast_sls
SOURCES
bvsls_opt_engine.cpp
bv_sls.cpp
bv_sls_eval.cpp
bv_sls_fixed.cpp
bv_sls_terms.cpp
sls_engine.cpp
sls_valuation.cpp
sat_ddfw.cpp
sls_arith_base.cpp
sls_arith_plugin.cpp
sls_array_plugin.cpp
sls_basic_plugin.cpp
sls_bv_engine.cpp
sls_bv_eval.cpp
sls_bv_fixed.cpp
sls_bv_plugin.cpp
sls_bv_terms.cpp
sls_bv_valuation.cpp
sls_context.cpp
sls_datatype_plugin.cpp
sls_euf_plugin.cpp
sls_smt_plugin.cpp
sls_smt_solver.cpp
COMPONENT_DEPENDENCIES
ast
euf
converters
normal_forms
)

364
src/ast/sls/bv_sls.cpp
View file

@ -1,364 +0,0 @@
/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
bv_sls.cpp
Abstract:
A Stochastic Local Search (SLS) engine
Uses invertibility conditions,
interval annotations
don't care annotations
Author:
Nikolaj Bjorner (nbjorner) 2024-02-07
--*/
#include "ast/sls/bv_sls.h"
#include "ast/ast_pp.h"
#include "ast/ast_ll_pp.h"
#include "params/sls_params.hpp"
namespace bv {
sls::sls(ast_manager& m, params_ref const& p):
m(m),
bv(m),
m_terms(m),
m_eval(m),
m_engine(m, p)
{
updt_params(p);
}
void sls::init() {
m_terms.init();
}
void sls::init_eval(std::function<bool(expr*, unsigned)>& eval) {
m_eval.init_eval(m_terms.assertions(), eval);
m_eval.tighten_range(m_terms.assertions());
init_repair();
}
void sls::init_repair() {
m_repair_down = UINT_MAX;
m_repair_up.reset();
m_repair_roots.reset();
for (auto* e : m_terms.assertions()) {
if (!m_eval.bval0(e)) {
m_eval.set(e, true);
m_repair_roots.insert(e->get_id());
}
}
for (auto* t : m_terms.terms()) {
if (t && !m_eval.re_eval_is_correct(t))
m_repair_roots.insert(t->get_id());
}
}
void sls::set_model() {
if (!m_set_model)
return;
if (m_repair_roots.size() >= m_min_repair_size)
return;
m_min_repair_size = m_repair_roots.size();
IF_VERBOSE(2, verbose_stream() << "(sls-update-model :num-unsat " << m_min_repair_size << ")\n");
m_set_model(*get_model());
}
void sls::init_repair_goal(app* t) {
m_eval.init_eval(t);
}
void sls::init_repair_candidates() {
m_to_repair.reset();
ptr_vector<expr> todo;
expr_fast_mark1 mark;
for (auto index : m_repair_roots)
todo.push_back(m_terms.term(index));
for (unsigned i = 0; i < todo.size(); ++i) {
expr* e = todo[i];
if (mark.is_marked(e))
continue;
mark.mark(e);
if (!is_app(e))
continue;
for (expr* arg : *to_app(e))
todo.push_back(arg);
if (is_uninterp_const(e))
m_to_repair.insert(e->get_id());
}
}
void sls::reinit_eval() {
init_repair_candidates();
if (m_to_repair.empty())
return;
// refresh the best model so far to a callback
set_model();
// add fresh units, if any
bool new_assertion = false;
while (m_get_unit) {
auto e = m_get_unit();
if (!e)
break;
new_assertion = true;
assert_expr(e);
}
if (new_assertion)
init();
std::function<bool(expr*, unsigned)> eval = [&](expr* e, unsigned i) {
unsigned id = e->get_id();
bool keep = !m_to_repair.contains(id);
if (m.is_bool(e)) {
if (m_eval.is_fixed0(e) || keep)
return m_eval.bval0(e);
if (m_engine_init) {
auto const& z = m_engine.get_value(e);
return rational(z).get_bit(0);
}
}
else if (bv.is_bv(e)) {
auto& w = m_eval.wval(e);
if (w.fixed.get(i) || keep)
return w.get_bit(i);
if (m_engine_init) {
auto const& z = m_engine.get_value(e);
return rational(z).get_bit(i);
}
}
return m_rand() % 2 == 0;
};
m_eval.init_eval(m_terms.assertions(), eval);
init_repair();
// m_engine_init = false;
}
std::pair<bool, app*> sls::next_to_repair() {
app* e = nullptr;
if (m_repair_down != UINT_MAX) {
e = m_terms.term(m_repair_down);
m_repair_down = UINT_MAX;
return { true, e };
}
if (!m_repair_up.empty()) {
unsigned index = m_repair_up.elem_at(m_rand(m_repair_up.size()));
m_repair_up.remove(index);
e = m_terms.term(index);
return { false, e };
}
while (!m_repair_roots.empty()) {
unsigned index = m_repair_roots.elem_at(m_rand(m_repair_roots.size()));
e = m_terms.term(index);
if (m_terms.is_assertion(e) && !m_eval.bval1(e)) {
SASSERT(m_eval.bval0(e));
return { true, e };
}
if (!m_eval.re_eval_is_correct(e)) {
init_repair_goal(e);
return { true, e };
}
m_repair_roots.remove(index);
}
return { false, nullptr };
}
lbool sls::search1() {
// init and init_eval were invoked
unsigned n = 0;
for (; n < m_config.m_max_repairs && m.inc(); ++n) {
auto [down, e] = next_to_repair();
if (!e)
return l_true;
IF_VERBOSE(20, trace_repair(down, e));
++m_stats.m_moves;
if (down)
try_repair_down(e);
else
try_repair_up(e);
}
return l_undef;
}
lbool sls::search2() {
lbool res = l_undef;
if (m_stats.m_restarts == 0)
res = m_engine(),
m_engine_init = true;
else if (m_stats.m_restarts % 1000 == 0)
res = m_engine.search_loop(),
m_engine_init = true;
if (res != l_undef)
m_engine_model = true;
return res;
}
lbool sls::operator()() {
lbool res = l_undef;
m_stats.reset();
m_stats.m_restarts = 0;
m_engine_model = false;
m_engine_init = false;
do {
res = search1();
if (res != l_undef)
break;
trace();
//res = search2();
if (res != l_undef)
break;
reinit_eval();
}
while (m.inc() && m_stats.m_restarts++ < m_config.m_max_restarts);
return res;
}
void sls::try_repair_down(app* e) {
unsigned n = e->get_num_args();
if (n == 0) {
m_eval.commit_eval(e);
for (auto p : m_terms.parents(e))
m_repair_up.insert(p->get_id());
return;
}
if (n == 2) {
auto d1 = get_depth(e->get_arg(0));
auto d2 = get_depth(e->get_arg(1));
unsigned s = m_rand(d1 + d2 + 2);
if (s <= d1 && m_eval.try_repair(e, 0)) {
set_repair_down(e->get_arg(0));
return;
}
if (m_eval.try_repair(e, 1)) {
set_repair_down(e->get_arg(1));
return;
}
if (m_eval.try_repair(e, 0)) {
set_repair_down(e->get_arg(0));
return;
}
}
else {
unsigned s = m_rand(n);
for (unsigned i = 0; i < n; ++i) {
auto j = (i + s) % n;
if (m_eval.try_repair(e, j)) {
set_repair_down(e->get_arg(j));
return;
}
}
}
IF_VERBOSE(3, verbose_stream() << "init-repair " << mk_bounded_pp(e, m) << "\n");
// repair was not successful, so reset the state to find a different way to repair
init_repair();
}
void sls::try_repair_up(app* e) {
if (m_terms.is_assertion(e))
m_repair_roots.insert(e->get_id());
else if (!m_eval.repair_up(e)) {
IF_VERBOSE(2, verbose_stream() << "repair-up "; trace_repair(true, e));
if (m_rand(10) != 0) {
m_eval.set_random(e);
m_repair_roots.insert(e->get_id());
}
else
init_repair();
}
else {
if (!m_eval.eval_is_correct(e)) {
verbose_stream() << "incorrect eval #" << e->get_id() << " " << mk_bounded_pp(e, m) << "\n";
}
SASSERT(m_eval.eval_is_correct(e));
for (auto p : m_terms.parents(e))
m_repair_up.insert(p->get_id());
}
}
model_ref sls::get_model() {
if (m_engine_model)
return m_engine.get_model();
model_ref mdl = alloc(model, m);
auto& terms = m_eval.sort_assertions(m_terms.assertions());
for (expr* e : terms) {
if (!is_uninterp_const(e))
continue;
auto f = to_app(e)->get_decl();
auto v = m_eval.get_value(to_app(e));
if (v)
mdl->register_decl(f, v);
}
terms.reset();
return mdl;
}
std::ostream& sls::display(std::ostream& out) {
auto& terms = m_eval.sort_assertions(m_terms.assertions());
for (expr* e : terms) {
out << e->get_id() << ": " << mk_bounded_pp(e, m, 1) << " ";
if (m_eval.is_fixed0(e))
out << "f ";
if (m_repair_up.contains(e->get_id()))
out << "u ";
if (m_repair_roots.contains(e->get_id()))
out << "r ";
m_eval.display_value(out, e);
out << "\n";
}
terms.reset();
return out;
}
void sls::updt_params(params_ref const& _p) {
sls_params p(_p);
m_config.m_max_restarts = p.max_restarts();
m_config.m_max_repairs = p.max_repairs();
m_rand.set_seed(p.random_seed());
m_terms.updt_params(_p);
params_ref q = _p;
q.set_uint("max_restarts", 10);
m_engine.updt_params(q);
}
std::ostream& sls::trace_repair(bool down, expr* e) {
verbose_stream() << (down ? "d #" : "u #")
<< e->get_id() << ": "
<< mk_bounded_pp(e, m, 1) << " ";
m_eval.display_value(verbose_stream(), e) << "\n";
return verbose_stream();
}
void sls::trace() {
IF_VERBOSE(2, verbose_stream()
<< "(bvsls :restarts " << m_stats.m_restarts
<< " :repair-up " << m_repair_up.size()
<< " :repair-roots " << m_repair_roots.size() << ")\n");
}
}

129
src/ast/sls/bv_sls.h
View file

@ -1,129 +0,0 @@
/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
bv_sls.h
Abstract:
A Stochastic Local Search (SLS) engine
Author:
Nikolaj Bjorner (nbjorner) 2024-02-07
--*/
#pragma once
#include "util/lbool.h"
#include "util/params.h"
#include "util/scoped_ptr_vector.h"
#include "util/uint_set.h"
#include "ast/ast.h"
#include "ast/sls/sls_stats.h"
#include "ast/sls/sls_powers.h"
#include "ast/sls/sls_valuation.h"
#include "ast/sls/bv_sls_terms.h"
#include "ast/sls/bv_sls_eval.h"
#include "ast/sls/sls_engine.h"
#include "ast/bv_decl_plugin.h"
#include "model/model.h"
namespace bv {
class sls {
struct config {
unsigned m_max_restarts = 1000;
unsigned m_max_repairs = 1000;
};
ast_manager& m;
bv_util bv;
sls_terms m_terms;
sls_eval m_eval;
sls_stats m_stats;
indexed_uint_set m_repair_up, m_repair_roots;
unsigned m_repair_down = UINT_MAX;
ptr_vector<expr> m_todo;
random_gen m_rand;
config m_config;
sls_engine m_engine;
bool m_engine_model = false;
bool m_engine_init = false;
std::function<expr_ref()> m_get_unit;
std::function<void(model& mdl)> m_set_model;
unsigned m_min_repair_size = UINT_MAX;
std::pair<bool, app*> next_to_repair();
void init_repair_goal(app* e);
void set_model();
void try_repair_down(app* e);
void try_repair_up(app* e);
void set_repair_down(expr* e) { m_repair_down = e->get_id(); }
lbool search1();
lbool search2();
void reinit_eval();
void init_repair();
void trace();
std::ostream& trace_repair(bool down, expr* e);
indexed_uint_set m_to_repair;
void init_repair_candidates();
public:
sls(ast_manager& m, params_ref const& p);
/**
* Add constraints
*/
void assert_expr(expr* e) { m_terms.assert_expr(e); m_engine.assert_expr(e); }
/*
* Invoke init after all expressions are asserted.
*/
void init();
/**
* Invoke init_eval to initialize, or re-initialize, values of
* uninterpreted constants.
*/
void init_eval(std::function<bool(expr*, unsigned)>& eval);
/**
* add callback to retrieve new units
*/
void init_unit(std::function<expr_ref()> get_unit) { m_get_unit = get_unit; }
/**
* Add callback to set model
*/
void set_model(std::function<void(model& mdl)> f) { m_set_model = f; }
/**
* Run (bounded) local search to find feasible assignments.
*/
lbool operator()();
void updt_params(params_ref const& p);
void collect_statistics(statistics& st) const { m_stats.collect_statistics(st); m_engine.collect_statistics(st); }
void reset_statistics() { m_stats.reset(); m_engine.reset_statistics(); }
unsigned get_num_moves() { return m_stats.m_moves + m_engine.get_stats().m_moves; }
std::ostream& display(std::ostream& out);
/**
* Retrieve valuation
*/
sls_valuation const& wval(expr* e) const { return m_eval.wval(e); }
model_ref get_model();
void cancel() { m.limit().cancel(); }
};
}

229
src/ast/sls/bv_sls_terms.cpp
View file

@ -1,229 +0,0 @@
/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
bv_sls.cpp
Abstract:
A Stochastic Local Search (SLS) engine
Uses invertibility conditions,
interval annotations
don't care annotations
Author:
Nikolaj Bjorner (nbjorner) 2024-02-07
--*/
#include "ast/ast_ll_pp.h"
#include "ast/sls/bv_sls.h"
#include "ast/rewriter/th_rewriter.h"
namespace bv {
sls_terms::sls_terms(ast_manager& m):
m(m),
bv(m),
m_rewriter(m),
m_assertions(m),
m_pinned(m),
m_translated(m),
m_terms(m){}
void sls_terms::assert_expr(expr* e) {
m_assertions.push_back(ensure_binary(e));
}
expr* sls_terms::ensure_binary(expr* e) {
expr* top = e;
m_pinned.push_back(e);
m_todo.push_back(e);
{
expr_fast_mark1 mark;
for (unsigned i = 0; i < m_todo.size(); ++i) {
expr* e = m_todo[i];
if (!is_app(e))
continue;
if (m_translated.get(e->get_id(), nullptr))
continue;
if (mark.is_marked(e))
continue;
mark.mark(e);
for (auto arg : *to_app(e))
m_todo.push_back(arg);
}
}
std::stable_sort(m_todo.begin(), m_todo.end(), [&](expr* a, expr* b) { return get_depth(a) < get_depth(b); });
for (expr* e : m_todo)
ensure_binary_core(e);
m_todo.reset();
return m_translated.get(top->get_id());
}
void sls_terms::ensure_binary_core(expr* e) {
if (m_translated.get(e->get_id(), nullptr))
return;
app* a = to_app(e);
auto arg = [&](unsigned i) {
return m_translated.get(a->get_arg(i)->get_id());
};
unsigned num_args = a->get_num_args();
expr_ref r(m);
#define FOLD_OP(oper) \
r = arg(0); \
for (unsigned i = 1; i < num_args; ++i)\
r = oper(r, arg(i)); \
if (m.is_and(e)) {
FOLD_OP(m.mk_and);
}
else if (m.is_or(e)) {
FOLD_OP(m.mk_or);
}
else if (m.is_xor(e)) {
FOLD_OP(m.mk_xor);
}
else if (bv.is_bv_and(e)) {
FOLD_OP(bv.mk_bv_and);
}
else if (bv.is_bv_or(e)) {
FOLD_OP(bv.mk_bv_or);
}
else if (bv.is_bv_xor(e)) {
FOLD_OP(bv.mk_bv_xor);
}
else if (bv.is_bv_add(e)) {
FOLD_OP(bv.mk_bv_add);
}
else if (bv.is_bv_mul(e)) {
FOLD_OP(bv.mk_bv_mul);
}
else if (bv.is_concat(e)) {
FOLD_OP(bv.mk_concat);
}
else if (m.is_distinct(e)) {
expr_ref_vector es(m);
for (unsigned i = 0; i < num_args; ++i)
for (unsigned j = i + 1; j < num_args; ++j)
es.push_back(m.mk_not(m.mk_eq(arg(i), arg(j))));
r = m.mk_and(es);
}
else if (bv.is_bv_sdiv(e) || bv.is_bv_sdiv0(e) || bv.is_bv_sdivi(e)) {
r = mk_sdiv(arg(0), arg(1));
}
else if (bv.is_bv_smod(e) || bv.is_bv_smod0(e) || bv.is_bv_smodi(e)) {
r = mk_smod(arg(0), arg(1));
}
else if (bv.is_bv_srem(e) || bv.is_bv_srem0(e) || bv.is_bv_sremi(e)) {
r = mk_srem(arg(0), arg(1));
}
else {
for (unsigned i = 0; i < num_args; ++i)
m_args.push_back(arg(i));
r = m.mk_app(a->get_decl(), num_args, m_args.data());
m_args.reset();
}
m_translated.setx(e->get_id(), r);
}
expr_ref sls_terms::mk_sdiv(expr* x, expr* y) {
// d = udiv(abs(x), abs(y))
// y = 0, x >= 0 -> -1
// y = 0, x < 0 -> 1
// x = 0, y != 0 -> 0
// x > 0, y < 0 -> -d
// x < 0, y > 0 -> -d
// x > 0, y > 0 -> d
// x < 0, y < 0 -> d
unsigned sz = bv.get_bv_size(x);
rational N = rational::power_of_two(sz);
expr_ref z(bv.mk_zero(sz), m);
expr* signx = bv.mk_ule(bv.mk_numeral(N / 2, sz), x);
expr* signy = bv.mk_ule(bv.mk_numeral(N / 2, sz), y);
expr* absx = m.mk_ite(signx, bv.mk_bv_neg(x), x);
expr* absy = m.mk_ite(signy, bv.mk_bv_neg(y), y);
expr* d = bv.mk_bv_udiv(absx, absy);
expr_ref r(m.mk_ite(m.mk_eq(signx, signy), d, bv.mk_bv_neg(d)), m);
r = m.mk_ite(m.mk_eq(z, y),
m.mk_ite(signx, bv.mk_one(sz), bv.mk_numeral(N - 1, sz)),
m.mk_ite(m.mk_eq(x, z), z, r));
m_rewriter(r);
return r;
}
expr_ref sls_terms::mk_smod(expr* x, expr* y) {
// u := umod(abs(x), abs(y))
// u = 0 -> 0
// y = 0 -> x
// x < 0, y < 0 -> -u
// x < 0, y >= 0 -> y - u
// x >= 0, y < 0 -> y + u
// x >= 0, y >= 0 -> u
unsigned sz = bv.get_bv_size(x);
expr_ref z(bv.mk_zero(sz), m);
expr_ref abs_x(m.mk_ite(bv.mk_sle(z, x), x, bv.mk_bv_neg(x)), m);
expr_ref abs_y(m.mk_ite(bv.mk_sle(z, y), y, bv.mk_bv_neg(y)), m);
expr_ref u(bv.mk_bv_urem(abs_x, abs_y), m);
expr_ref r(m);
r = m.mk_ite(m.mk_eq(u, z), z,
m.mk_ite(m.mk_eq(y, z), x,
m.mk_ite(m.mk_and(bv.mk_sle(z, x), bv.mk_sle(z, x)), u,
m.mk_ite(bv.mk_sle(z, x), bv.mk_bv_add(y, u),
m.mk_ite(bv.mk_sle(z, y), bv.mk_bv_sub(y, u), bv.mk_bv_neg(u))))));
m_rewriter(r);
return r;
}
expr_ref sls_terms::mk_srem(expr* x, expr* y) {
// y = 0 -> x
// else x - sdiv(x, y) * y
expr_ref r(m);
r = m.mk_ite(m.mk_eq(y, bv.mk_zero(bv.get_bv_size(x))),
x, bv.mk_bv_sub(x, bv.mk_bv_mul(y, mk_sdiv(x, y))));
m_rewriter(r);
return r;
}
void sls_terms::init() {
// populate terms
expr_fast_mark1 mark;
for (expr* e : m_assertions)
m_todo.push_back(e);
while (!m_todo.empty()) {
expr* e = m_todo.back();
m_todo.pop_back();
if (mark.is_marked(e) || !is_app(e))
continue;
mark.mark(e);
m_terms.setx(e->get_id(), to_app(e));
for (expr* arg : *to_app(e))
m_todo.push_back(arg);
}
// populate parents
m_parents.reset();
m_parents.reserve(m_terms.size());
for (expr* e : m_terms) {
if (!e || !is_app(e))
continue;
for (expr* arg : *to_app(e))
m_parents[arg->get_id()].push_back(e);
}
m_assertion_set.reset();
for (auto a : m_assertions)
m_assertion_set.insert(a->get_id());
}
void sls_terms::updt_params(params_ref const& p) {
params_ref q = p;
q.set_bool("flat", false);
m_rewriter.updt_params(q);
}
}

79
src/ast/sls/bv_sls_terms.h
View file

@ -1,79 +0,0 @@
/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
bv_sls_terms.h
Abstract:
A Stochastic Local Search (SLS) engine
Author:
Nikolaj Bjorner (nbjorner) 2024-02-07
--*/
#pragma once
#include "util/lbool.h"
#include "util/params.h"
#include "util/scoped_ptr_vector.h"
#include "util/uint_set.h"
#include "ast/ast.h"
#include "ast/rewriter/th_rewriter.h"
#include "ast/sls/sls_stats.h"
#include "ast/sls/sls_powers.h"
#include "ast/sls/sls_valuation.h"
#include "ast/bv_decl_plugin.h"
namespace bv {
class sls_terms {
ast_manager& m;
bv_util bv;
th_rewriter m_rewriter;
ptr_vector<expr> m_todo, m_args;
expr_ref_vector m_assertions, m_pinned, m_translated;
app_ref_vector m_terms;
vector<ptr_vector<expr>> m_parents;
tracked_uint_set m_assertion_set;
expr* ensure_binary(expr* e);
void ensure_binary_core(expr* e);
expr_ref mk_sdiv(expr* x, expr* y);
expr_ref mk_smod(expr* x, expr* y);
expr_ref mk_srem(expr* x, expr* y);
public:
sls_terms(ast_manager& m);
void updt_params(params_ref const& p);
/**
* Add constraints
*/
void assert_expr(expr* e);
/**
* Initialize structures: assertions, parents, terms
*/
void init();
/**
* Accessors.
*/
ptr_vector<expr> const& parents(expr* e) const { return m_parents[e->get_id()]; }
expr_ref_vector const& assertions() const { return m_assertions; }
app* term(unsigned id) const { return m_terms.get(id); }
app_ref_vector const& terms() const { return m_terms; }
bool is_assertion(expr* e) const { return m_assertion_set.contains(e->get_id()); }
};
}

2
src/ast/sls/bvsls_opt_engine.h
View file

@ -18,7 +18,7 @@ Notes:
--*/
#pragma once
#include "ast/sls/sls_engine.h"
#include "ast/sls/sls_bv_engine.h"
class bvsls_opt_engine : public sls_engine {
sls_tracker & m_hard_tracker;

350
src/sat/sat_ddfw.cpp → src/ast/sls/sat_ddfw.cpp
View file

@ -11,8 +11,7 @@
Author:
Nikolaj Bjorner, Marijn Heule 2019-4-23
Nikolaj Bjorner, Marijn Heule 2019-4-23
Notes:
@ -26,20 +25,18 @@
--*/
#include "util/luby.h"
#include "sat/sat_ddfw.h"
#include "sat/sat_solver.h"
#include "sat/sat_params.hpp"
#include "util/trace.h"
#include "ast/sls/sat_ddfw.h"
#include "params/sat_params.hpp"
namespace sat {
ddfw::~ddfw() {
for (auto& ci : m_clauses)
m_alloc.del_clause(ci.m_clause);
}
lbool ddfw::check(unsigned sz, literal const* assumptions, parallel* p) {
init(sz, assumptions);
flet<parallel*> _p(m_par, p);
lbool ddfw::check(unsigned sz, literal const* assumptions) {
init(sz, assumptions);
if (m_plugin)
check_with_plugin();
else
@ -52,36 +49,42 @@ namespace sat {
void ddfw::check_without_plugin() {
while (m_limit.inc() && m_min_sz > 0) {
if (should_reinit_weights()) do_reinit_weights();
else if (do_flip<false>());
else if (do_flip());
else if (should_restart()) do_restart();
else if (should_parallel_sync()) do_parallel_sync();
else if (m_parallel_sync && m_parallel_sync());
else shift_weights();
}
}
void ddfw::check_with_plugin() {
m_plugin->init_search();
m_steps_since_progress = 0;
unsigned steps = 0;
while (m_min_sz > 0 && m_steps_since_progress++ <= 1500000) {
if (should_reinit_weights()) do_reinit_weights();
else if (steps % 5000 == 0) shift_weights(), m_plugin->on_rescale();
else if (should_restart()) do_restart(), m_plugin->on_restart();
else if (do_flip<true>());
else if (do_literal_flip<true>());
else if (should_parallel_sync()) do_parallel_sync();
else shift_weights(), m_plugin->on_rescale();
++steps;
if (m_min_sz <= m_unsat.size())
save_best_values();
try {
while (m_min_sz > 0 && m_limit.inc()) {
if (should_reinit_weights()) do_reinit_weights();
else if (steps % 5000 == 0) shift_weights(), m_plugin->on_rescale();
else if (should_restart()) do_restart(), m_plugin->on_restart();
else if (do_flip());
else shift_weights(), m_plugin->on_rescale();
//verbose_stream() << "steps: " << steps << " min_sz: " << m_min_sz << " unsat: " << m_unsat.size() << "\n";
++steps;
}
}
catch (z3_exception& ex) {
IF_VERBOSE(0, verbose_stream() << "Exception: " << ex.msg() << "\n");
throw;
}
m_plugin->finish_search();
}
void ddfw::log() {
double sec = m_stopwatch.get_current_seconds();
double kflips_per_sec = (m_flips - m_last_flips) / (1000.0 * sec);
double kflips_per_sec = sec > 0 ? (m_flips - m_last_flips) / (1000.0 * sec) : 0.0;
if (m_last_flips == 0) {
IF_VERBOSE(1, verbose_stream() << "(sat.ddfw :unsat :models :kflips/sec :flips :restarts :reinits :unsat_vars :shifts";
if (m_par) verbose_stream() << " :par";
verbose_stream() << ")\n");
}
IF_VERBOSE(1, verbose_stream() << "(sat.ddfw "
@ -93,43 +96,37 @@ namespace sat {
<< std::setw(11) << m_reinit_count
<< std::setw(13) << m_unsat_vars.size()
<< std::setw(9) << m_shifts;
if (m_par) verbose_stream() << std::setw(10) << m_parsync_count;
verbose_stream() << ")\n");
m_stopwatch.start();
m_last_flips = m_flips;
}
template<bool uses_plugin>
bool ddfw::do_flip() {
double reward = 0;
bool_var v = pick_var<uses_plugin>(reward);
return apply_flip<uses_plugin>(v, reward);
bool_var v = pick_var(reward);
//verbose_stream() << "flip " << v << " " << reward << "\n";
return apply_flip(v, reward);
}
template<bool uses_plugin>
bool ddfw::apply_flip(bool_var v, double reward) {
if (v == null_bool_var)
return false;
if (reward > 0 || (reward == 0 && m_rand(100) <= m_config.m_use_reward_zero_pct)) {
if (uses_plugin && is_external(v))
m_plugin->flip(v);
else
flip(v);
if (m_unsat.size() <= m_min_sz)
flip(v);
if (m_unsat.size() <= m_min_sz)
save_best_values();
return true;
}
return false;
}
template<bool uses_plugin>
bool_var ddfw::pick_var(double& r) {
double sum_pos = 0;
unsigned n = 1;
bool_var v0 = null_bool_var;
for (bool_var v : m_unsat_vars) {
r = uses_plugin ? plugin_reward(v) : reward(v);
r = reward(v);
if (r > 0.0)
sum_pos += score(r);
else if (r == 0.0 && sum_pos == 0 && (m_rand() % (n++)) == 0)
@ -138,7 +135,7 @@ namespace sat {
if (sum_pos > 0) {
double lim_pos = ((double) m_rand() / (1.0 + m_rand.max_value())) * sum_pos;
for (bool_var v : m_unsat_vars) {
r = uses_plugin && is_external(v) ? m_vars[v].m_last_reward : reward(v);
r = reward(v);
if (r > 0) {
lim_pos -= score(r);
if (lim_pos <= 0)
@ -154,96 +151,41 @@ namespace sat {
return m_unsat_vars.elem_at(m_rand(m_unsat_vars.size()));
}
template<bool uses_plugin>
bool ddfw::do_literal_flip() {
double reward = 1;
return apply_flip<uses_plugin>(pick_literal_var<uses_plugin>(), reward);
}
/*
* Pick a random false literal from a satisfied clause such that
* the literal has zero break count and positive reward.
*/
template<bool uses_plugin>
bool_var ddfw::pick_literal_var() {
#if false
unsigned sz = m_clauses.size();
unsigned start = rand();
for (unsigned i = 0; i < 100; ++i) {
unsigned cl = (i + start) % sz;
if (m_unsat.contains(cl))
continue;
for (auto lit : *m_clauses[cl].m_clause) {
if (is_true(lit))
continue;
double r = uses_plugin ? plugin_reward(lit.var()) : reward(lit.var());
if (r < 0)
continue;
//verbose_stream() << "false " << r << " " << lit << "\n";
return lit.var();
}
}
#endif
return null_bool_var;
}
void ddfw::add(unsigned n, literal const* c) {
clause* cls = m_alloc.mk_clause(n, c, false);
void ddfw::add(unsigned n, literal const* c) {
unsigned idx = m_clauses.size();
m_clauses.push_back(clause_info(cls, m_config.m_init_clause_weight));
for (literal lit : *cls) {
m_clauses.push_back(clause_info(n, c, m_config.m_init_clause_weight));
if (n > 2)
++m_num_non_binary_clauses;
for (literal lit : m_clauses.back().m_clause) {
m_use_list.reserve(2*(lit.var()+1));
m_vars.reserve(lit.var()+1);
m_use_list[lit.index()].push_back(idx);
}
}
sat::bool_var ddfw::add_var() {
auto v = m_vars.size();
m_vars.reserve(v + 1);
return v;
}
void ddfw::reserve_vars(unsigned n) {
m_vars.reserve(n);
}
/**
* Remove the last clause that was added
*/
void ddfw::del() {
auto& info = m_clauses.back();
for (literal lit : *info.m_clause)
for (literal lit : info.m_clause)
m_use_list[lit.index()].pop_back();
m_alloc.del_clause(info.m_clause);
m_clauses.pop_back();
if (m_unsat.contains(m_clauses.size()))
m_unsat.remove(m_clauses.size());
}
void ddfw::add(solver const& s) {
set_seed(s.get_config().m_random_seed);
for (auto& ci : m_clauses)
m_alloc.del_clause(ci.m_clause);
m_clauses.reset();
m_use_list.reset();
m_num_non_binary_clauses = 0;
unsigned trail_sz = s.init_trail_size();
for (unsigned i = 0; i < trail_sz; ++i) {
add(1, s.m_trail.data() + i);
}
unsigned sz = s.m_watches.size();
for (unsigned l_idx = 0; l_idx < sz; ++l_idx) {
literal l1 = ~to_literal(l_idx);
watch_list const & wlist = s.m_watches[l_idx];
for (watched const& w : wlist) {
if (!w.is_binary_non_learned_clause())
continue;
literal l2 = w.get_literal();
if (l1.index() > l2.index())
continue;
literal ls[2] = { l1, l2 };
add(2, ls);
}
}
for (clause* c : s.m_clauses) {
add(c->size(), c->begin());
}
m_num_non_binary_clauses = s.m_clauses.size();
}
void ddfw::add_assumptions() {
for (unsigned i = 0; i < m_assumptions.size(); ++i)
add(1, m_assumptions.data() + i);
@ -264,8 +206,9 @@ namespace sat {
for (unsigned v = 0; v < num_vars(); ++v) {
value(v) = (m_rand() % 2) == 0; // m_use_list[lit.index()].size() >= m_use_list[nlit.index()].size();
}
init_clause_data();
flatten_use_list();
if (!flatten_use_list())
init_clause_data();
m_reinit_count = 0;
m_reinit_next = m_config.m_reinit_base;
@ -273,29 +216,23 @@ namespace sat {
m_restart_count = 0;
m_restart_next = m_config.m_restart_base*2;
m_parsync_count = 0;
m_parsync_next = m_config.m_parsync_base;
m_min_sz = m_unsat.size();
m_min_sz = m_clauses.size();
m_flips = 0;
m_last_flips = 0;
m_shifts = 0;
m_stopwatch.start();
}
void ddfw::reinit(solver& s, bool_vector const& phase) {
add(s);
void ddfw::reinit() {
add_assumptions();
for (unsigned v = 0; v < phase.size(); ++v) {
value(v) = phase[v];
reward(v) = 0;
make_count(v) = 0;
}
init_clause_data();
flatten_use_list();
}
void ddfw::flatten_use_list() {
bool ddfw::flatten_use_list() {
if (num_vars() == m_use_list_vars && m_clauses.size() == m_use_list_clauses)
return false;
m_use_list_vars = num_vars();
m_use_list_clauses = m_clauses.size();
m_use_list_index.reset();
m_flat_use_list.reset();
for (auto const& ul : m_use_list) {
@ -303,6 +240,8 @@ namespace sat {
m_flat_use_list.append(ul);
}
m_use_list_index.push_back(m_flat_use_list.size());
init_clause_data();
return true;
}
void ddfw::flip(bool_var v) {
@ -310,15 +249,19 @@ namespace sat {
literal lit = literal(v, !value(v));
literal nlit = ~lit;
SASSERT(is_true(lit));
for (unsigned cls_idx : use_list(*this, lit)) {
clause_info& ci = m_clauses[cls_idx];
for (unsigned cls_idx : use_list(lit)) {
clause_info& ci = m_clauses[cls_idx];
ci.del(lit);
double w = ci.m_weight;
// cls becomes false: flip any variable in clause to receive reward w
switch (ci.m_num_trues) {
case 0: {
#if 0
if (ci.m_clause.size() == 1)
verbose_stream() << "flipping unit clause " << ci << "\n";
#endif
m_unsat.insert_fresh(cls_idx);
clause const& c = get_clause(cls_idx);
auto const& c = get_clause(cls_idx);
for (literal l : c) {
inc_reward(l, w);
inc_make(l);
@ -333,7 +276,7 @@ namespace sat {
break;
}
}
for (unsigned cls_idx : use_list(*this, nlit)) {
for (unsigned cls_idx : use_list(nlit)) {
clause_info& ci = m_clauses[cls_idx];
double w = ci.m_weight;
// the clause used to have a single true (pivot) literal, now it has two.
@ -341,7 +284,7 @@ namespace sat {
switch (ci.m_num_trues) {
case 0: {
m_unsat.remove(cls_idx);
clause const& c = get_clause(cls_idx);
auto const& c = get_clause(cls_idx);
for (literal l : c) {
dec_reward(l, w);
dec_make(l);
@ -388,13 +331,13 @@ namespace sat {
for (unsigned v = 0; v < num_vars(); ++v) {
make_count(v) = 0;
reward(v) = 0;
}
}
m_unsat_vars.reset();
m_unsat.reset();
unsigned sz = m_clauses.size();
for (unsigned i = 0; i < sz; ++i) {
auto& ci = m_clauses[i];
clause const& c = get_clause(i);
auto const& c = get_clause(i);
ci.m_trues = 0;
ci.m_num_trues = 0;
for (literal lit : c)
@ -415,13 +358,15 @@ namespace sat {
break;
}
}
if (m_unsat.size() < m_min_sz)
save_best_values();
}
bool ddfw::should_restart() {
return m_flips >= m_restart_next;
}
void ddfw::do_restart() {
void ddfw::do_restart() {
reinit_values();
init_clause_data();
m_restart_next += m_config.m_restart_base*get_luby(++m_restart_count);
@ -445,52 +390,39 @@ namespace sat {
}
}
bool ddfw::should_parallel_sync() {
return m_par != nullptr && m_flips >= m_parsync_next;
}
void ddfw::save_priorities() {
m_probs.reset();
for (unsigned v = 0; v < num_vars(); ++v)
m_probs.push_back(-m_vars[v].m_reward_avg);
}
void ddfw::do_parallel_sync() {
if (m_par->from_solver(*this))
m_par->to_solver(*this);
++m_parsync_count;
m_parsync_next *= 3;
m_parsync_next /= 2;
}
void ddfw::save_model() {
m_model.reserve(num_vars());
for (unsigned i = 0; i < num_vars(); ++i)
m_model[i] = to_lbool(value(i));
save_priorities();
if (m_plugin)
m_plugin->on_save_model();
m_plugin->on_save_model();
}
void ddfw::save_best_values() {
if (m_unsat.size() < m_min_sz) {
m_steps_since_progress = 0;
if (m_unsat.size() < 50 || m_min_sz * 10 > m_unsat.size() * 11)
save_model();
}
if (m_save_best_values)
return;
if (m_plugin && !m_unsat.empty())
return;
flet<bool> _save_best_values(m_save_best_values, true);
bool do_save_model = ((m_unsat.size() < m_min_sz || m_unsat.empty()) &&
((m_unsat.size() < 50 || m_min_sz * 10 > m_unsat.size() * 11)));
if (do_save_model)
save_model();
if (m_unsat.size() < m_min_sz) {
m_models.reset();
// skip saving the first model.
for (unsigned v = 0; v < num_vars(); ++v) {
int& b = bias(v);
if (abs(b) > 3) {
b = b > 0 ? 3 : -3;
}
}
m_min_sz = m_unsat.size();
}
unsigned h = value_hash();
unsigned occs = 0;
bool contains = m_models.find(h, occs);
@ -504,8 +436,7 @@ namespace sat {
if (occs > 100) {
m_restart_next = m_flips;
m_models.erase(h);
}
m_min_sz = m_unsat.size();
}
}
unsigned ddfw::value_hash() const {
@ -538,11 +469,11 @@ namespace sat {
unsigned ddfw::select_max_same_sign(unsigned cf_idx) {
auto& ci = m_clauses[cf_idx];
unsigned cl = UINT_MAX; // clause pointer to same sign, max weight satisfied clause.
clause const& c = *ci.m_clause;
auto const& c = ci.m_clause;
double max_weight = m_init_weight;
unsigned n = 1;
for (literal lit : c) {
for (unsigned cn_idx : use_list(*this, lit)) {
for (unsigned cn_idx : use_list(lit)) {
auto& cn = m_clauses[cn_idx];
if (select_clause(max_weight, cn, n)) {
cl = cn_idx;
@ -568,15 +499,20 @@ namespace sat {
}
unsigned ddfw::select_random_true_clause() {
unsigned num_clauses = m_clauses.size();
unsigned rounds = 100 * num_clauses;
for (unsigned i = 0; i < rounds; ++i) {
unsigned num_clauses = m_clauses.size();
for (unsigned i = 0; i < num_clauses; ++i) {
unsigned idx = (m_rand() * m_rand()) % num_clauses;
auto & cn = m_clauses[idx];
if (cn.is_true() && cn.m_weight >= m_init_weight)
return idx;
}
return UINT_MAX;
unsigned n = 0, idx = UINT_MAX;
for (unsigned i = 0; i < num_clauses; ++i) {
auto& cn = m_clauses[i];
if (cn.is_true() && cn.m_weight >= m_init_weight && (m_rand() % (++n)) == 0)
idx = i;
}
return idx;
}
// 1% chance to disregard neighbor
@ -590,6 +526,7 @@ namespace sat {
void ddfw::shift_weights() {
++m_shifts;
bool shifted = false;
for (unsigned to_idx : m_unsat) {
SASSERT(!m_clauses[to_idx].is_true());
unsigned from_idx = select_max_same_sign(to_idx);
@ -597,28 +534,75 @@ namespace sat {
from_idx = select_random_true_clause();
if (from_idx == UINT_MAX)
continue;
shifted = true;
auto & cn = m_clauses[from_idx];
SASSERT(cn.is_true());
double w = calculate_transfer_weight(cn.m_weight);
transfer_weight(from_idx, to_idx, w);
}
//verbose_stream() << m_shifts << " " << m_flips << " " << shifted << "\n";
if (!shifted && m_restart_next > m_flips)
m_restart_next = m_flips + (m_restart_next - m_flips) / 2;
// DEBUG_CODE(invariant(););
}
// apply unit propagation.
void ddfw::simplify() {
verbose_stream() << "simplify\n";
sat::literal_vector units;
uint_set unit_set;
for (unsigned i = 0; i < m_clauses.size(); ++i) {
auto& ci = m_clauses[i];
if (ci.m_clause.size() != 1)
continue;
auto lit = ci.m_clause[0];
units.push_back(lit);
unit_set.insert(lit.index());
m_use_list[lit.index()].reset();
m_use_list[lit.index()].push_back(i);
}
auto is_unit = [&](sat::literal lit) {
return unit_set.contains(lit.index());
};
sat::literal_vector new_clause;
for (unsigned i = 0; i < units.size(); ++i) {
auto lit = units[i];
for (auto cidx : m_use_list[(~lit).index()]) {
auto& ci = m_clauses[cidx];
if (ci.m_clause.size() == 1)
continue;
new_clause.reset();
for (auto l : ci) {
if (!is_unit(~l))
new_clause.push_back(l);
}
if (new_clause.size() == 1) {
verbose_stream() << "new unit " << lit << " " << ci << " -> " << new_clause << "\n";
}
m_clauses[cidx] = sat::clause_info(new_clause.size(), new_clause.data(), m_config.m_init_clause_weight);
if (new_clause.size() == 1) {
units.push_back(new_clause[0]);
unit_set.insert(new_clause[0].index());
}
}
}
for (auto unit : units)
m_use_list[(~unit).index()].reset();
}
std::ostream& ddfw::display(std::ostream& out) const {
unsigned num_cls = m_clauses.size();
for (unsigned i = 0; i < num_cls; ++i) {
out << get_clause(i) << " ";
out << get_clause(i) << " nt: ";
auto const& ci = m_clauses[i];
out << ci.m_num_trues << " " << ci.m_weight << "\n";
}
for (unsigned v = 0; v < num_vars(); ++v) {
out << v << ": rw " << reward(v) << "\n";
out << ci.m_num_trues << " w: " << ci.m_weight << "\n";
}
for (unsigned v = 0; v < num_vars(); ++v)
out << (is_true(literal(v, false)) ? "" : "-") << v << " rw: " << get_reward(v) << "\n";
out << "unsat vars: ";
for (bool_var v : m_unsat_vars) {
out << v << " ";
}
for (bool_var v : m_unsat_vars)
out << v << " ";
out << "\n";
return out;
}
@ -681,6 +665,20 @@ namespace sat {
m_config.m_reinit_base = p.ddfw_reinit_base();
m_config.m_restart_base = p.ddfw_restart_base();
}
void ddfw::collect_statistics(statistics& st) const {
st.update("sls-ddfw-flips", (double)m_flips);
st.update("sls-ddfw-restarts", m_restart_count);
st.update("sls-ddfw-reinits", m_reinit_count);
st.update("sls-ddfw-shifts", (double)m_shifts);
}
void ddfw::reset_statistics() {
m_flips = 0;
m_restart_count = 0;
m_reinit_count = 0;
m_shifts = 0;
}
}

161
src/sat/sat_ddfw.h → src/ast/sls/sat_ddfw.h
View file

@ -24,54 +24,27 @@
#include "util/rlimit.h"
#include "util/params.h"
#include "util/ema.h"
#include "sat/sat_clause.h"
#include "sat/sat_types.h"
#include "util/sat_sls.h"
#include "util/map.h"
#include "util/sat_literal.h"
#include "util/statistics.h"
#include "util/stopwatch.h"
namespace arith {
class sls;
}
namespace sat {
class solver;
class parallel;
class local_search_plugin {
public:
virtual ~local_search_plugin() {}
virtual void init_search() = 0;
virtual void finish_search() = 0;
virtual void flip(bool_var v) = 0;
virtual double reward(bool_var v) = 0;
virtual void on_rescale() = 0;
virtual void on_save_model() = 0;
virtual void on_restart() = 0;
};
class ddfw : public i_local_search {
friend class arith::sls;
public:
struct clause_info {
clause_info(clause* cl, double init_weight): m_weight(init_weight), m_clause(cl) {}
double m_weight; // weight of clause
unsigned m_trues = 0; // set of literals that are true
unsigned m_num_trues = 0; // size of true set
clause* m_clause;
bool is_true() const { return m_num_trues > 0; }
void add(literal lit) { ++m_num_trues; m_trues += lit.index(); }
void del(literal lit) { SASSERT(m_num_trues > 0); --m_num_trues; m_trues -= lit.index(); }
};
class use_list {
ddfw& p;
unsigned i;
public:
use_list(ddfw& p, literal lit) :
p(p), i(lit.index()) {}
unsigned const* begin() { return p.m_flat_use_list.data() + p.m_use_list_index[i]; }
unsigned const* end() { return p.m_flat_use_list.data() + p.m_use_list_index[i + 1]; }
unsigned size() const { return p.m_use_list_index[i + 1] - p.m_use_list_index[i]; }
};
class ddfw {
friend class ddfw_wrapper;
protected:
struct config {
@ -95,45 +68,47 @@ namespace sat {
};
struct var_info {
var_info() {}
bool m_value = false;
double m_reward = 0;
double m_last_reward = 0;
unsigned m_make_count = 0;
int m_bias = 0;
bool m_external = false;
ema m_reward_avg = 1e-5;
};
config m_config;
reslimit m_limit;
clause_allocator m_alloc;
svector<clause_info> m_clauses;
vector<clause_info> m_clauses;
literal_vector m_assumptions;
svector<var_info> m_vars; // var -> info
svector<double> m_probs; // var -> probability of flipping
svector<double> m_scores; // reward -> score
model m_model; // var -> best assignment
svector<lbool> m_model; // var -> best assignment
unsigned m_init_weight = 2;
vector<unsigned_vector> m_use_list;
unsigned_vector m_flat_use_list;
unsigned_vector m_use_list_index;
unsigned m_use_list_vars = 0, m_use_list_clauses = 0;
indexed_uint_set m_unsat;
indexed_uint_set m_unsat_vars; // set of variables that are in unsat clauses
random_gen m_rand;
uint64_t m_last_flips_for_shift = 0;
unsigned m_num_non_binary_clauses = 0;
unsigned m_restart_count = 0, m_reinit_count = 0, m_parsync_count = 0;
uint64_t m_restart_next = 0, m_reinit_next = 0, m_parsync_next = 0;
unsigned m_restart_count = 0, m_reinit_count = 0;
uint64_t m_restart_next = 0, m_reinit_next = 0;
uint64_t m_flips = 0, m_last_flips = 0, m_shifts = 0;
unsigned m_min_sz = 0, m_steps_since_progress = 0;
unsigned m_min_sz = UINT_MAX;
u_map<unsigned> m_models;
stopwatch m_stopwatch;
unsigned_vector m_num_models;
bool m_save_best_values = false;
parallel* m_par;
local_search_plugin* m_plugin = nullptr;
scoped_ptr<local_search_plugin> m_plugin = nullptr;
std::function<bool(void)> m_parallel_sync;
void flatten_use_list();
bool flatten_use_list();
/**
* TBD: map reward value to a score, possibly through an exponential function, such as
@ -141,31 +116,20 @@ namespace sat {
*/
inline double score(double r) { return r; }
inline unsigned num_vars() const { return m_vars.size(); }
inline unsigned& make_count(bool_var v) { return m_vars[v].m_make_count; }
inline bool& value(bool_var v) { return m_vars[v].m_value; }
inline bool value(bool_var v) const { return m_vars[v].m_value; }
inline double& reward(bool_var v) { return m_vars[v].m_reward; }
inline double& reward(bool_var v) { return m_vars[v].m_reward; }
inline double reward(bool_var v) const { return m_vars[v].m_reward; }
inline double plugin_reward(bool_var v) { return is_external(v) ? (m_vars[v].m_last_reward = m_plugin->reward(v)) : reward(v); }
void set_external(bool_var v) { m_vars[v].m_external = true; }
inline bool is_external(bool_var v) const { return m_vars[v].m_external; }
inline int& bias(bool_var v) { return m_vars[v].m_bias; }
unsigned value_hash() const;
inline bool is_true(literal lit) const { return value(lit.var()) != lit.sign(); }
inline clause const& get_clause(unsigned idx) const { return *m_clauses[idx].m_clause; }
inline sat::literal_vector const& get_clause(unsigned idx) const { return m_clauses[idx].m_clause; }
inline double get_weight(unsigned idx) const { return m_clauses[idx].m_weight; }
@ -193,20 +157,12 @@ namespace sat {
void check_without_plugin();
// flip activity
template<bool uses_plugin>
bool do_flip();
template<bool uses_plugin>
bool_var pick_var(double& reward);
template<bool uses_plugin>
bool apply_flip(bool_var v, double reward);
template<bool uses_plugin>
bool do_literal_flip();
template<bool uses_plugin>
bool_var pick_literal_var();
void save_best_values();
void save_model();
@ -226,11 +182,7 @@ namespace sat {
void do_restart();
void reinit_values();
unsigned select_random_true_clause();
// parallel integration
bool should_parallel_sync();
void do_parallel_sync();
unsigned select_random_true_clause();
void log();
@ -240,8 +192,6 @@ namespace sat {
void invariant();
void add(unsigned sz, literal const* c);
void del();
void add_assumptions();
@ -252,48 +202,79 @@ namespace sat {
public:
ddfw(): m_par(nullptr) {}
ddfw() {}
~ddfw() override;
~ddfw();
void set(local_search_plugin* p) { m_plugin = p; }
void set_plugin(local_search_plugin* p) { m_plugin = p; }
lbool check(unsigned sz, literal const* assumptions, parallel* p) override;
lbool check(unsigned sz, literal const* assumptions);
void updt_params(params_ref const& p) override;
void updt_params(params_ref const& p);
model const& get_model() const override { return m_model; }
svector<lbool> const& get_model() const { return m_model; }
reslimit& rlimit() override { return m_limit; }
reslimit& rlimit() { return m_limit; }
void set_seed(unsigned n) override { m_rand.set_seed(n); }
void set_seed(unsigned n) { m_rand.set_seed(n); }
void add(solver const& s) override;
bool get_value(bool_var v) const override { return value(v); }
bool get_value(bool_var v) const { return value(v); }
std::ostream& display(std::ostream& out) const;
// for parallel integration
unsigned num_non_binary_clauses() const override { return m_num_non_binary_clauses; }
void reinit(solver& s, bool_vector const& phase) override;
unsigned num_non_binary_clauses() const { return m_num_non_binary_clauses; }
void collect_statistics(statistics& st) const override {}
void collect_statistics(statistics& st) const;
double get_priority(bool_var v) const override { return m_probs[v]; }
void reset_statistics();
double get_priority(bool_var v) const { return m_probs[v]; }
// access clause information and state of Boolean search
indexed_uint_set& unsat_set() { return m_unsat; }
unsigned num_clauses() const { return m_clauses.size(); }
indexed_uint_set const& unsat_set() const { return m_unsat; }
vector<clause_info> const& clauses() const { return m_clauses; }
clause_info& get_clause_info(unsigned idx) { return m_clauses[idx]; }
clause_info const& get_clause_info(unsigned idx) const { return m_clauses[idx]; }
void remove_assumptions();
void flip(bool_var v);
use_list get_use_list(literal lit) { return use_list(*this, lit); }
inline double get_reward(bool_var v) const { return m_vars[v].m_reward; }
double get_reward_avg(bool_var v) const { return m_vars[v].m_reward_avg; }
inline int& bias(bool_var v) { return m_vars[v].m_bias; }
void reserve_vars(unsigned n);
void add(unsigned sz, literal const* c);
sat::bool_var add_var();
void reinit();
void force_restart() { m_restart_next = m_flips; }
inline unsigned num_vars() const { return m_vars.size(); }
void simplify();
ptr_iterator<unsigned> use_list(literal lit) {
flatten_use_list();
unsigned i = lit.index();
auto const* b = m_flat_use_list.data() + m_use_list_index[i];
auto const* e = m_flat_use_list.data() + m_use_list_index[i + 1];
return { b, e };
}
};
}

2326
src/ast/sls/sls_arith_base.cpp Normal file
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File diff suppressed because it is too large Load diff

292
src/ast/sls/sls_arith_base.h Normal file
View file

@ -0,0 +1,292 @@
/*++
Copyright (c) 2020 Microsoft Corporation
Module Name:
sls_arith_base.h
Abstract:
Theory plugin for arithmetic local search
Author:
Nikolaj Bjorner (nbjorner) 2020-09-08
--*/
#pragma once
#include "util/obj_pair_set.h"
#include "util/checked_int64.h"
#include "util/optional.h"
#include "ast/ast_trail.h"
#include "ast/arith_decl_plugin.h"
#include "ast/sls/sls_context.h"
namespace sls {
using theory_var = int;
// local search portion for arithmetic
template<typename num_t>
class arith_base : public plugin {
enum class ineq_kind { EQ, LE, LT};
enum class var_sort { INT, REAL };
struct bound { bool is_strict = false; num_t value; };
typedef unsigned var_t;
typedef unsigned atom_t;
struct config {
double cb = 2.85;
unsigned L = 20;
unsigned t = 45;
unsigned max_no_improve = 500000;
double sp = 0.0003;
};
struct stats {
unsigned m_num_steps = 0;
};
public:
struct linear_term {
vector<std::pair<num_t, var_t>> m_args;
num_t m_coeff{ 0 };
};
struct nonlinear_coeff {
var_t v; // variable or multiplier containing x
num_t coeff; // coeff of v in inequality
unsigned p; // power
};
typedef svector<std::pair<unsigned, unsigned>> monomial_t;
// encode args <= bound, args = bound, args < bound
struct ineq : public linear_term {
vector<std::pair<var_t, vector<nonlinear_coeff>>> m_nonlinear;
vector<monomial_t> m_monomials;
ineq_kind m_op = ineq_kind::LE;
num_t m_args_value;
bool m_is_linear = true;
bool is_true() const;
std::ostream& display(std::ostream& out) const;
};
private:
class var_info {
num_t m_range{ 100000000 };
num_t m_update_value{ 0 };
unsigned m_update_timestamp = 0;
public:
var_info(expr* e, var_sort k): m_expr(e), m_sort(k) {}
expr* m_expr;
num_t m_value{ 0 };
num_t m_best_value{ 0 };
var_sort m_sort;
arith_op_kind m_op = arith_op_kind::LAST_ARITH_OP;
unsigned m_def_idx = UINT_MAX;
vector<std::pair<num_t, sat::bool_var>> m_bool_vars;
unsigned_vector m_muls;
unsigned_vector m_adds;
optional<bound> m_lo, m_hi;
// retrieve temporary value during an update.
void set_update_value(num_t const& v, unsigned timestamp) {
m_update_value = v;
m_update_timestamp = timestamp;
}
num_t const& get_update_value(unsigned ts) const {
return ts == m_update_timestamp ? m_update_value : m_value;
}
bool in_range(num_t const& n) const {
if (-m_range < n && n < m_range)
return true;
if (m_lo && !m_hi)
return n < m_lo->value + m_range;
if (!m_lo && m_hi)
return n > m_hi->value - m_range;
return false;
}
unsigned m_tabu_pos = 0, m_tabu_neg = 0;
unsigned m_last_pos = 0, m_last_neg = 0;
bool is_tabu(unsigned step, num_t const& delta) {
return (delta > 0 ? m_tabu_pos : m_tabu_neg) > step;
}
void set_step(unsigned step, unsigned tabu_step, num_t const& delta) {
if (delta > 0)
m_tabu_pos = tabu_step, m_last_pos = step;
else
m_tabu_neg = tabu_step, m_last_neg = step;
}
};
struct mul_def {
unsigned m_var;
monomial_t m_monomial;
};
struct add_def : public linear_term {
unsigned m_var;
};
struct op_def {
unsigned m_var = UINT_MAX;
arith_op_kind m_op = LAST_ARITH_OP;
unsigned m_arg1, m_arg2;
};
struct var_change {
unsigned m_var;
num_t m_delta;
double m_score;
};
stats m_stats;
config m_config;
scoped_ptr_vector<ineq> m_bool_vars;
vector<var_info> m_vars;
vector<mul_def> m_muls;
vector<add_def> m_adds;
vector<op_def> m_ops;
unsigned_vector m_expr2var;
svector<double> m_probs;
bool m_dscore_mode = false;
vector<var_change> m_updates;
var_t m_last_var = 0;
sat::literal m_last_literal = sat::null_literal;
num_t m_last_delta { 0 };
bool m_use_tabu = true;
unsigned m_updates_max_size = 45;
arith_util a;
svector<double> m_prob_break;
void invariant();
void invariant(ineq const& i);
unsigned get_num_vars() const { return m_vars.size(); }
bool eval_is_correct(var_t v);
bool repair_mul(mul_def const& md);
bool repair_add(add_def const& ad);
bool repair_mod(op_def const& od);
bool repair_idiv(op_def const& od);
bool repair_div(op_def const& od);
bool repair_rem(op_def const& od);
bool repair_power(op_def const& od);
bool repair_abs(op_def const& od);
bool repair_to_int(op_def const& od);
bool repair_to_real(op_def const& od);
bool repair(sat::literal lit);
bool in_bounds(var_t v, num_t const& value);
bool is_fixed(var_t v);
bool is_linear(var_t x, vector<nonlinear_coeff> const& nlc, num_t& b);
bool is_quadratic(var_t x, vector<nonlinear_coeff> const& nlc, num_t& a, num_t& b);
num_t mul_value_without(var_t m, var_t x);
void add_update(var_t v, num_t delta);
bool is_permitted_update(var_t v, num_t const& delta, num_t& delta_out);
unsigned m_update_timestamp = 0;
svector<var_t> m_update_trail;
bool check_update(var_t v, num_t new_value);
void apply_checked_update();
num_t value1(var_t v);
vector<num_t> m_factors;
vector<num_t> const& factor(num_t n);
num_t root_of(unsigned n, num_t a);
num_t power_of(num_t a, unsigned k);
struct monomial_elem {
num_t other_product;
var_t v;
unsigned p; // power
};
// double reward(sat::literal lit);
bool sign(sat::bool_var v) const { return !ctx.is_true(sat::literal(v, false)); }
ineq* atom(sat::bool_var bv) const { return m_bool_vars.get(bv, nullptr); }
num_t dtt(bool sign, ineq const& ineq) const { return dtt(sign, ineq.m_args_value, ineq); }
num_t dtt(bool sign, num_t const& args_value, ineq const& ineq) const;
num_t dtt(bool sign, ineq const& ineq, var_t v, num_t const& new_value) const;
num_t dtt(bool sign, ineq const& ineq, num_t const& coeff, num_t const& delta) const;
num_t dts(unsigned cl, var_t v, num_t const& new_value) const;
num_t compute_dts(unsigned cl) const;
bool is_mul(var_t v) const { return m_vars[v].m_op == arith_op_kind::OP_MUL; }
bool is_add(var_t v) const { return m_vars[v].m_op == arith_op_kind::OP_ADD; }
mul_def const& get_mul(var_t v) const { SASSERT(is_mul(v)); return m_muls[m_vars[v].m_def_idx]; }
add_def const& get_add(var_t v) const { SASSERT(is_add(v)); return m_adds[m_vars[v].m_def_idx]; }
bool update(var_t v, num_t const& new_value);
bool apply_update();
bool find_nl_moves(sat::literal lit);
bool find_lin_moves(sat::literal lit);
bool find_reset_moves(sat::literal lit);
void add_reset_update(var_t v);
void find_linear_moves(ineq const& i, var_t x, num_t const& coeff, num_t const& sum);
void find_quadratic_moves(ineq const& i, var_t x, num_t const& a, num_t const& b, num_t const& sum);
double compute_score(var_t x, num_t const& delta);
void save_best_values();
var_t mk_var(expr* e);
var_t mk_term(expr* e);
var_t mk_op(arith_op_kind k, expr* e, expr* x, expr* y);
void add_arg(linear_term& term, num_t const& c, var_t v);
void add_args(linear_term& term, expr* e, num_t const& sign);
ineq& new_ineq(ineq_kind op, num_t const& bound);
void init_ineq(sat::bool_var bv, ineq& i);
num_t divide(var_t v, num_t const& delta, num_t const& coeff);
num_t divide_floor(var_t v, num_t const& a, num_t const& b);
num_t divide_ceil(var_t v, num_t const& a, num_t const& b);
void init_bool_var_assignment(sat::bool_var v);
bool is_int(var_t v) const { return m_vars[v].m_sort == var_sort::INT; }
num_t value(var_t v) const { return m_vars[v].m_value; }
num_t const& get_update_value(var_t v) const { return m_vars[v].get_update_value(m_update_timestamp); }
bool is_num(expr* e, num_t& i);
expr_ref from_num(sort* s, num_t const& n);
void check_ineqs();
void init_bool_var(sat::bool_var bv);
void initialize_unit(sat::literal lit);
void add_le(var_t v, num_t const& n);
void add_ge(var_t v, num_t const& n);
void add_lt(var_t v, num_t const& n);
void add_gt(var_t v, num_t const& n);
std::ostream& display(std::ostream& out, var_t v) const;
std::ostream& display(std::ostream& out, add_def const& ad) const;
std::ostream& display(std::ostream& out, mul_def const& md) const;
public:
arith_base(context& ctx);
~arith_base() override {}
void register_term(expr* e) override;
bool set_value(expr* e, expr* v) override;
expr_ref get_value(expr* e) override;
void initialize() override;
void propagate_literal(sat::literal lit) override;
bool propagate() override;
void repair_up(app* e) override;
bool repair_down(app* e) override;
void repair_literal(sat::literal lit) override;
bool is_sat() override;
void on_rescale() override;
void on_restart() override;
std::ostream& display(std::ostream& out) const override;
void collect_statistics(statistics& st) const override;
void reset_statistics() override;
};
inline std::ostream& operator<<(std::ostream& out, typename arith_base<checked_int64<true>>::ineq const& ineq) {
return ineq.display(out);
}
inline std::ostream& operator<<(std::ostream& out, typename arith_base<rational>::ineq const& ineq) {
return ineq.display(out);
}
}

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/*++
Copyright (c) 2023 Microsoft Corporation
Module Name:
sls_arith_plugin.cpp
Abstract:
Local search dispatch for NIA
Author:
Nikolaj Bjorner (nbjorner) 2023-02-07
--*/
#include "ast/sls/sls_arith_plugin.h"
#include "ast/ast_ll_pp.h"
namespace sls {
#define WITH_FALLBACK(_fn_) \
if (m_arith64) { \
try {\
return m_arith64->_fn_;\
}\
catch (overflow_exception&) {\
throw;\
init_backup();\
}\
}\
return m_arith->_fn_; \
#define APPLY_BOTH(_fn_) \
if (m_arith64) { \
try {\
m_arith64->_fn_;\
}\
catch (overflow_exception&) {\
throw;\
init_backup();\
}\
}\
m_arith->_fn_; \
arith_plugin::arith_plugin(context& ctx) :
plugin(ctx), m_shared(ctx.get_manager()) {
m_arith64 = alloc(arith_base<checked_int64<true>>, ctx);
m_arith = alloc(arith_base<rational>, ctx);
m_arith64 = nullptr;
if (m_arith)
m_fid = m_arith->fid();
else
m_fid = m_arith64->fid();
}
void arith_plugin::init_backup() {
m_arith64 = nullptr;
}
void arith_plugin::register_term(expr* e) {
APPLY_BOTH(register_term(e));
}
expr_ref arith_plugin::get_value(expr* e) {
WITH_FALLBACK(get_value(e));
}
void arith_plugin::initialize() {
APPLY_BOTH(initialize());
}
void arith_plugin::propagate_literal(sat::literal lit) {
WITH_FALLBACK(propagate_literal(lit));
}
bool arith_plugin::propagate() {
WITH_FALLBACK(propagate());
}
bool arith_plugin::is_sat() {
WITH_FALLBACK(is_sat());
}
void arith_plugin::on_rescale() {
APPLY_BOTH(on_rescale());
}
void arith_plugin::on_restart() {
WITH_FALLBACK(on_restart());
}
std::ostream& arith_plugin::display(std::ostream& out) const {
if (m_arith64)
return m_arith64->display(out);
else
return m_arith->display(out);
}
bool arith_plugin::repair_down(app* e) {
WITH_FALLBACK(repair_down(e));
}
void arith_plugin::repair_up(app* e) {
WITH_FALLBACK(repair_up(e));
}
void arith_plugin::repair_literal(sat::literal lit) {
WITH_FALLBACK(repair_literal(lit));
}
bool arith_plugin::set_value(expr* e, expr* v) {
WITH_FALLBACK(set_value(e, v));
}
void arith_plugin::collect_statistics(statistics& st) const {
if (m_arith64)
m_arith64->collect_statistics(st);
else
m_arith->collect_statistics(st);
}
void arith_plugin::reset_statistics() {
if (m_arith)
m_arith->reset_statistics();
if (m_arith64)
m_arith64->reset_statistics();
}
}

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/*++
Copyright (c) 2020 Microsoft Corporation
Module Name:
sls_arith_plugin.h
Abstract:
Theory plugin for arithmetic local search
Author:
Nikolaj Bjorner (nbjorner) 2024-07-05
--*/
#pragma once
#include "ast/sls/sls_context.h"
#include "ast/sls/sls_arith_base.h"
namespace sls {
class arith_plugin : public plugin {
scoped_ptr<arith_base<checked_int64<true>>> m_arith64;
scoped_ptr<arith_base<rational>> m_arith;
expr_ref_vector m_shared;
void init_backup();
public:
arith_plugin(context& ctx);
~arith_plugin() override {}
void register_term(expr* e) override;
expr_ref get_value(expr* e) override;
void initialize() override;
void propagate_literal(sat::literal lit) override;
bool propagate() override;
bool repair_down(app* e) override;
void repair_up(app* e) override;
void repair_literal(sat::literal lit) override;
bool is_sat() override;
void on_rescale() override;
void on_restart() override;
std::ostream& display(std::ostream& out) const override;
bool set_value(expr* e, expr* v) override;
void collect_statistics(statistics& st) const override;
void reset_statistics() override;
};
}

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/*++
Copyright (c) 2020 Microsoft Corporation
Module Name:
sls_array_plugin.cpp
Abstract:
Theory plugin for arrays local search
Author:
Nikolaj Bjorner (nbjorner) 2024-07-06
--*/
#include "ast/sls/sls_array_plugin.h"
#include "ast/ast_ll_pp.h"
#include "ast/ast_pp.h"
namespace sls {
array_plugin::array_plugin(context& ctx):
plugin(ctx),
a(m)
{
m_fid = a.get_family_id();
}
bool array_plugin::is_sat() {
if (!m_has_arrays)
return true;
m_g = alloc(euf::egraph, m);
m_kv = nullptr;
init_egraph(*m_g);
saturate_store(*m_g);
return true;
}
// b ~ a[i -> v]
// ensure b[i] ~ v
// ensure b[j] ~ a[j] for j != i
void array_plugin::saturate_store(euf::egraph& g) {
unsigned sz = 0;
while (sz < g.nodes().size()) {
sz = g.nodes().size();
for (unsigned i = 0; i < sz; ++i) {
auto n = g.nodes()[i];
if (!a.is_store(n->get_expr()))
continue;
force_store_axiom1(g, n);
for (auto p : euf::enode_parents(n->get_root()))
if (a.is_select(p->get_expr()))
force_store_axiom2_down(g, n, p);
auto arr = n->get_arg(0);
for (auto p : euf::enode_parents(arr->get_root()))
if (a.is_select(p->get_expr()))
force_store_axiom2_up(g, n, p);
}
}
display(verbose_stream() << "saturated\n");
}
euf::enode* array_plugin::mk_select(euf::egraph& g, euf::enode* b, euf::enode* sel) {
auto arity = get_array_arity(b->get_sort());
ptr_buffer<expr> args;
ptr_buffer<euf::enode> eargs;
args.push_back(b->get_expr());
eargs.push_back(b);
for (unsigned i = 1; i <= arity; ++i) {
auto idx = sel->get_arg(i);
eargs.push_back(idx);
args.push_back(idx->get_expr());
}
expr_ref esel(a.mk_select(args), m);
auto n = g.find(esel);
return n ? n : g.mk(esel, 0, eargs.size(), eargs.data());
}
// ensure a[i->v][i] = v exists in the e-graph
void array_plugin::force_store_axiom1(euf::egraph& g, euf::enode* n) {
SASSERT(a.is_store(n->get_expr()));
auto val = n->get_arg(n->num_args() - 1);
auto nsel = mk_select(g, n, n);
if (are_distinct(nsel, val))
add_store_axiom1(n->get_app());
else {
g.merge(nsel, val, nullptr);
VERIFY(g.propagate());
}
}
// i /~ j, b ~ a[i->v], b[j] occurs -> a[j] = b[j]
void array_plugin::force_store_axiom2_down(euf::egraph& g, euf::enode* sto, euf::enode* sel) {
SASSERT(a.is_store(sto->get_expr()));
SASSERT(a.is_select(sel->get_expr()));
if (sel->get_arg(0)->get_root() != sto->get_root())
return;
if (eq_args(sto, sel))
return;
auto nsel = mk_select(g, sto->get_arg(0), sel);
if (are_distinct(nsel, sel))
add_store_axiom2(sto->get_app(), sel->get_app());
else {
g.merge(nsel, sel, nullptr);
VERIFY(g.propagate());
}
}
// a ~ b, i /~ j, b[j] occurs -> a[i -> v][j] = b[j]
void array_plugin::force_store_axiom2_up(euf::egraph& g, euf::enode* sto, euf::enode* sel) {
SASSERT(a.is_store(sto->get_expr()));
SASSERT(a.is_select(sel->get_expr()));
if (sel->get_arg(0)->get_root() != sto->get_arg(0)->get_root())
return;
if (eq_args(sto, sel))
return;
auto nsel = mk_select(g, sto, sel);
if (are_distinct(nsel, sel))
add_store_axiom2(sto->get_app(), sel->get_app());
else {
g.merge(nsel, sel, nullptr);
VERIFY(g.propagate());
}
}
bool array_plugin::are_distinct(euf::enode* a, euf::enode* b) {
a = a->get_root();
b = b->get_root();
return a->interpreted() && b->interpreted() && a != b; // TODO work with nested arrays?
}
bool array_plugin::eq_args(euf::enode* sto, euf::enode* sel) {
SASSERT(a.is_store(sto->get_expr()));
SASSERT(a.is_select(sel->get_expr()));
unsigned arity = get_array_arity(sto->get_sort());
for (unsigned i = 1; i < arity; ++i) {
if (sto->get_arg(i)->get_root() != sel->get_arg(i)->get_root())
return false;
}
return true;
}
void array_plugin::add_store_axiom1(app* sto) {
if (!m_add_conflicts)
return;
ptr_vector<expr> args;
args.push_back(sto);
for (unsigned i = 1; i < sto->get_num_args() - 1; ++i)
args.push_back(sto->get_arg(i));
expr_ref sel(a.mk_select(args), m);
expr_ref eq(m.mk_eq(sel, to_app(sto)->get_arg(sto->get_num_args() - 1)), m);
verbose_stream() << "add store axiom 1 " << mk_bounded_pp(sto, m) << "\n";
ctx.add_clause(eq);
}
void array_plugin::add_store_axiom2(app* sto, app* sel) {
if (!m_add_conflicts)
return;
ptr_vector<expr> args1, args2;
args1.push_back(sto);
args2.push_back(sto->get_arg(0));
for (unsigned i = 1; i < sel->get_num_args() - 1; ++i) {
args1.push_back(sel->get_arg(i));
args2.push_back(sel->get_arg(i));
}
expr_ref sel1(a.mk_select(args1), m);
expr_ref sel2(a.mk_select(args2), m);
expr_ref eq(m.mk_eq(sel1, sel2), m);
expr_ref_vector ors(m);
ors.push_back(eq);
for (unsigned i = 1; i < sel->get_num_args() - 1; ++i)
ors.push_back(m.mk_eq(sel->get_arg(i), sto->get_arg(i)));
verbose_stream() << "add store axiom 2 " << mk_bounded_pp(sto, m) << " " << mk_bounded_pp(sel, m) << "\n";
ctx.add_clause(m.mk_or(ors));
}
void array_plugin::init_egraph(euf::egraph& g) {
ptr_vector<euf::enode> args;
for (auto t : ctx.subterms()) {
args.reset();
if (is_app(t))
for (auto* arg : *to_app(t))
args.push_back(g.find(arg));
euf::enode* n1, * n2;
n1 = g.find(t);
n1 = n1 ? n1 : g.mk(t, 0, args.size(), args.data());
if (a.is_array(t))
continue;
auto v = ctx.get_value(t);
verbose_stream() << "init " << mk_bounded_pp(t, m) << " := " << mk_bounded_pp(v, m) << "\n";
n2 = g.find(v);
n2 = n2 ? n2: g.mk(v, 0, 0, nullptr);
g.merge(n1, n2, nullptr);
}
for (auto lit : ctx.root_literals()) {
if (!ctx.is_true(lit) || lit.sign())
continue;
auto e = ctx.atom(lit.var());
expr* x, * y;
if (e && m.is_eq(e, x, y))
g.merge(g.find(x), g.find(y), nullptr);
}
display(verbose_stream());
}
void array_plugin::init_kv(euf::egraph& g, kv& kv) {
for (auto n : g.nodes()) {
if (!n->is_root() || !a.is_array(n->get_expr()))
continue;
kv.insert(n, select2value());
for (auto p : euf::enode_parents(n)) {
if (!a.is_select(p->get_expr()))
continue;
if (p->get_arg(0)->get_root() != n->get_root())
continue;
auto val = p->get_root();
kv[n].insert(select_args(p), val);
}
}
display(verbose_stream());
}
expr_ref array_plugin::get_value(expr* e) {
SASSERT(a.is_array(e));
if (!m_g) {
m_g = alloc(euf::egraph, m);
init_egraph(*m_g);
flet<bool> _strong(m_add_conflicts, false);
saturate_store(*m_g);
}
if (!m_kv) {
m_kv = alloc(kv);
init_kv(*m_g, *m_kv);
}
auto& kv = *m_kv;
auto n = m_g->find(e)->get_root();
expr_ref r(n->get_expr(), m);
for (auto [k, v] : kv[n]) {
ptr_vector<expr> args;
args.push_back(r);
args.push_back(k.sel->get_arg(1)->get_expr());
args.push_back(v->get_expr());
r = a.mk_store(args);
}
return r;
}
std::ostream& array_plugin::display(std::ostream& out) const {
if (m_g)
m_g->display(out);
if (m_kv) {
for (auto& [n, kvs] : *m_kv) {
out << m_g->pp(n) << " -> {";
char const* sp = "";
for (auto& [k, v] : kvs) {
out << sp;
for (unsigned i = 1; i < k.sel->num_args(); ++i)
out << m_g->pp(k.sel->get_arg(i)->get_root()) << " ";
out << "-> " << m_g->pp(v);
sp = " ";
}
out << "}\n";
}
}
return out;
}
}

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/*++
Copyright (c) 2020 Microsoft Corporation
Module Name:
sls_array_plugin.h
Abstract:
Theory plugin for arrays local search
Author:
Nikolaj Bjorner (nbjorner) 2024-07-06
--*/
#pragma once
#include "ast/sls/sls_context.h"
#include "ast/array_decl_plugin.h"
#include "ast/euf/euf_egraph.h"
namespace sls {
class array_plugin : public plugin {
struct select_args {
euf::enode* sel = nullptr;
select_args(euf::enode* s) : sel(s) {}
select_args() {}
};
struct select_args_hash {
unsigned operator()(select_args const& a) const {
unsigned h = 0;
for (unsigned i = 1; i < a.sel->num_args(); ++i)
h ^= a.sel->get_arg(i)->get_root()->hash();
return h;
};
};
struct select_args_eq {
bool operator()(select_args const& a, select_args const& b) const {
SASSERT(a.sel->num_args() == b.sel->num_args());
for (unsigned i = 1; i < a.sel->num_args(); ++i)
if (a.sel->get_arg(i)->get_root() != b.sel->get_arg(i)->get_root())
return false;
return true;
}
};
typedef map<select_args, euf::enode*, select_args_hash, select_args_eq> select2value;
typedef obj_map<euf::enode, select2value> kv;
array_util a;
scoped_ptr<euf::egraph> m_g;
scoped_ptr<kv> m_kv;
bool m_add_conflicts = true;
bool m_has_arrays = false;
void init_egraph(euf::egraph& g);
void init_kv(euf::egraph& g, kv& kv);
void saturate_store(euf::egraph& g);
void force_store_axiom1(euf::egraph& g, euf::enode* n);
void force_store_axiom2_down(euf::egraph& g, euf::enode* sto, euf::enode* sel);
void force_store_axiom2_up(euf::egraph& g, euf::enode* sto, euf::enode* sel);
void add_store_axiom1(app* sto);
void add_store_axiom2(app* sto, app* sel);
bool are_distinct(euf::enode* a, euf::enode* b);
bool eq_args(euf::enode* sto, euf::enode* sel);
euf::enode* mk_select(euf::egraph& g, euf::enode* b, euf::enode* sel);
public:
array_plugin(context& ctx);
~array_plugin() override {}
void register_term(expr* e) override { if (a.is_array(e->get_sort())) m_has_arrays = true; }
expr_ref get_value(expr* e) override;
void initialize() override { m_g = nullptr; }
void propagate_literal(sat::literal lit) override { m_g = nullptr; }
bool propagate() override { return false; }
bool repair_down(app* e) override { return true; }
void repair_up(app* e) override {}
void repair_literal(sat::literal lit) override { m_g = nullptr; }
bool is_sat() override;
void on_rescale() override {}
void on_restart() override {}
std::ostream& display(std::ostream& out) const override;
bool set_value(expr* e, expr* v) override { return false; }
void collect_statistics(statistics& st) const override {}
void reset_statistics() override {}
};
}

210
src/ast/sls/sls_basic_plugin.cpp Normal file
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@ -0,0 +1,210 @@
/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
sls_basic_plugin.cpp
Abstract:
Local search dispatch for Boolean connectives
Author:
Nikolaj Bjorner (nbjorner) 2024-07-07
--*/
#include "ast/sls/sls_basic_plugin.h"
#include "ast/ast_ll_pp.h"
#include "ast/ast_pp.h"
#include "ast/ast_util.h"
namespace sls {
expr_ref basic_plugin::get_value(expr* e) {
return expr_ref(m.mk_bool_val(bval0(e)), m);
}
bool basic_plugin::is_basic(expr* e) const {
if (!e || !is_app(e))
return false;
if (m.is_ite(e) && !m.is_bool(e) && false)
return true;
if (m.is_xor(e) && to_app(e)->get_num_args() != 2)
return true;
if (m.is_distinct(e))
return true;
return false;
}
void basic_plugin::propagate_literal(sat::literal lit) {
}
void basic_plugin::register_term(expr* e) {
expr* c, * th, * el;
if (m.is_ite(e, c, th, el) && !m.is_bool(e)) {
ctx.add_clause(m.mk_or(mk_not(m, c), m.mk_eq(e, th)));
ctx.add_clause(m.mk_or(c, m.mk_eq(e, el)));
}
}
void basic_plugin::initialize() {
}
bool basic_plugin::propagate() {
return false;
}
bool basic_plugin::is_sat() {
return true;
}
std::ostream& basic_plugin::display(std::ostream& out) const {
return out;
}
bool basic_plugin::set_value(expr* e, expr* v) {
if (!m.is_bool(e))
return false;
SASSERT(m.is_true(v) || m.is_false(v));
return set_value(e, m.is_true(v));
}
expr_ref basic_plugin::eval_ite(app* e) {
expr* c, * th, * el;
VERIFY(m.is_ite(e, c, th, el));
if (bval0(c))
return ctx.get_value(th);
else
return ctx.get_value(el);
}
expr_ref basic_plugin::eval_distinct(app* e) {
for (unsigned i = 0; i < e->get_num_args(); ++i) {
for (unsigned j = i + 1; j < e->get_num_args(); ++j) {
if (bval0(e->get_arg(i)) == bval0(e->get_arg(j)))
return expr_ref(m.mk_false(), m);
}
}
return expr_ref(m.mk_true(), m);
}
expr_ref basic_plugin::eval_xor(app* e) {
bool b = false;
for (expr* arg : *e)
b ^= bval0(arg);
return expr_ref(m.mk_bool_val(b), m);
}
bool basic_plugin::bval0(expr* e) const {
SASSERT(m.is_bool(e));
return ctx.is_true(ctx.mk_literal(e));
}
bool basic_plugin::try_repair(app* e, unsigned i) {
switch (e->get_decl_kind()) {
case OP_XOR:
return try_repair_xor(e, i);
case OP_ITE:
return try_repair_ite(e, i);
case OP_DISTINCT:
return try_repair_distinct(e, i);
default:
return true;
}
}
bool basic_plugin::try_repair_xor(app* e, unsigned i) {
auto child = e->get_arg(i);
bool bv = false;
for (unsigned j = 0; j < e->get_num_args(); ++j)
if (j != i)
bv ^= bval0(e->get_arg(j));
bool ev = bval0(e);
return set_value(child, ev != bv);
}
bool basic_plugin::try_repair_ite(app* e, unsigned i) {
if (m.is_bool(e))
return true;
auto child = e->get_arg(i);
auto cond = e->get_arg(0);
bool c = bval0(cond);
if (i == 0) {
auto eval = ctx.get_value(e);
auto eval1 = ctx.get_value(e->get_arg(1));
auto eval2 = ctx.get_value(e->get_arg(2));
if (eval == eval1 && eval == eval2)
return true;
if (eval == eval1)
return set_value(cond, true);
if (eval == eval2)
return set_value(cond, false);
return false;
}
if (c != (i == 1))
return false;
if (m.is_value(child))
return false;
bool r = ctx.set_value(child, ctx.get_value(e));
verbose_stream() << "repair-ite-down " << mk_bounded_pp(e, m) << " @ " << mk_bounded_pp(child, m) << " := " << ctx.get_value(e) << " success " << r << "\n";
return r;
}
void basic_plugin::repair_up(app* e) {
expr* c, * th, * el;
expr_ref val(m);
if (!is_basic(e))
return;
if (m.is_ite(e, c, th, el) && !m.is_bool(e))
val = eval_ite(e);
else if (m.is_xor(e))
val = eval_xor(e);
else if (m.is_distinct(e))
val = eval_distinct(e);
else
return;
verbose_stream() << "repair-up " << mk_bounded_pp(e, m) << " " << val << "\n";
if (!ctx.set_value(e, val))
ctx.new_value_eh(e);
}
void basic_plugin::repair_literal(sat::literal lit) {
}
bool basic_plugin::repair_down(app* e) {
if (!is_basic(e))
return true;
if (m.is_xor(e) && eval_xor(e) == ctx.get_value(e))
return true;
if (m.is_ite(e) && eval_ite(e) == ctx.get_value(e))
return true;
if (m.is_distinct(e) && eval_distinct(e) == ctx.get_value(e))
return true;
verbose_stream() << "basic repair down " << mk_bounded_pp(e, m) << "\n";
unsigned n = e->get_num_args();
unsigned s = ctx.rand(n);
for (unsigned i = 0; i < n; ++i) {
auto j = (i + s) % n;
if (try_repair(e, j))
return true;
}
return false;
}
bool basic_plugin::try_repair_distinct(app* e, unsigned i) {
NOT_IMPLEMENTED_YET();
return false;
}
bool basic_plugin::set_value(expr* e, bool b) {
auto lit = ctx.mk_literal(e);
if (ctx.is_true(lit) != b) {
ctx.flip(lit.var());
ctx.new_value_eh(e);
}
return true;
}
}

58
src/ast/sls/sls_basic_plugin.h Normal file
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@ -0,0 +1,58 @@
/*++
Copyright (c) 2020 Microsoft Corporation
Module Name:
sls_basic_plugin.h
Author:
Nikolaj Bjorner (nbjorner) 2024-07-05
--*/
#pragma once
#include "ast/sls/sls_context.h"
namespace sls {
class basic_plugin : public plugin {
expr_mark m_axiomatized;
bool is_basic(expr* e) const;
bool bval0(expr* e) const;
bool try_repair(app* e, unsigned i);
bool try_repair_xor(app* e, unsigned i);
bool try_repair_ite(app* e, unsigned i);
bool try_repair_distinct(app* e, unsigned i);
bool set_value(expr* e, bool b);
expr_ref eval_ite(app* e);
expr_ref eval_distinct(app* e);
expr_ref eval_xor(app* e);
public:
basic_plugin(context& ctx) :
plugin(ctx) {
m_fid = basic_family_id;
}
~basic_plugin() override {}
void register_term(expr* e) override;
expr_ref get_value(expr* e) override;
void initialize() override;
void propagate_literal(sat::literal lit) override;
bool propagate() override;
bool repair_down(app* e) override;
void repair_up(app* e) override;
void repair_literal(sat::literal lit) override;
bool is_sat() override;
void on_rescale() override {}
void on_restart() override {}
std::ostream& display(std::ostream& out) const override;
bool set_value(expr* e, expr* v) override;
void collect_statistics(statistics& st) const override {}
void reset_statistics() override {}
};
}

2
src/ast/sls/sls_engine.cpp → src/ast/sls/sls_bv_engine.cpp
View file

@ -26,7 +26,7 @@ Notes:
#include "util/luby.h"
#include "params/sls_params.hpp"
#include "ast/sls/sls_engine.h"
#include "ast/sls/sls_bv_engine.h"
sls_engine::sls_engine(ast_manager & m, params_ref const & p) :

4
src/ast/sls/sls_engine.h → src/ast/sls/sls_bv_engine.h
View file

@ -23,8 +23,8 @@ Notes:
#include "ast/converters/model_converter.h"
#include "ast/sls/sls_stats.h"
#include "ast/sls/sls_tracker.h"
#include "ast/sls/sls_evaluator.h"
#include "ast/sls/sls_bv_tracker.h"
#include "ast/sls/sls_bv_evaluator.h"
class sls_engine {

1062
src/ast/sls/bv_sls_eval.cpp → src/ast/sls/sls_bv_eval.cpp
View file

File diff suppressed because it is too large Load diff

145
src/ast/sls/bv_sls_eval.h → src/ast/sls/sls_bv_eval.h
View file

@ -17,79 +17,81 @@ Author:
#pragma once
#include "ast/ast.h"
#include "ast/sls/sls_valuation.h"
#include "ast/sls/bv_sls_fixed.h"
#include "ast/sls/sls_bv_valuation.h"
#include "ast/sls/sls_bv_fixed.h"
#include "ast/sls/sls_context.h"
#include "ast/bv_decl_plugin.h"
namespace bv {
namespace sls {
class sls_fixed;
class bv_terms;
class sls_eval_plugin {
public:
virtual ~sls_eval_plugin() {}
};
class sls_eval {
using bvect = sls::bvect;
class bv_eval {
struct config {
unsigned m_prob_randomize_extract = 50;
};
friend class sls_fixed;
friend class sls::bv_fixed;
friend class sls_test;
ast_manager& m;
sls::context& ctx;
sls::bv_terms& terms;
bv_util bv;
sls_fixed m_fix;
sls::bv_fixed m_fix;
mutable mpn_manager mpn;
ptr_vector<expr> m_todo;
random_gen m_rand;
config m_config;
bool_vector m_fixed;
scoped_ptr_vector<sls_eval_plugin> m_plugins;
scoped_ptr_vector<sls::bv_valuation> m_values; // expr-id -> bv valuation
scoped_ptr_vector<sls_valuation> m_values; // expr-id -> bv valuation
bool_vector m_eval; // expr-id -> boolean valuation
bool_vector m_fixed; // expr-id -> is Boolean fixed
mutable bvect m_tmp, m_tmp2, m_tmp3, m_tmp4, m_zero, m_one, m_minus_one;
mutable bvect m_tmp, m_tmp2, m_tmp3, m_tmp4, m_mul_tmp, m_zero, m_one, m_minus_one;
bvect m_a, m_b, m_nextb, m_nexta, m_aux;
using bvval = sls_valuation;
using bvval = sls::bv_valuation;
void init_eval_basic(app* e);
void init_eval_bv(app* e);
ptr_vector<expr> m_restore;
vector<ptr_vector<expr>> m_update_stack;
expr_mark m_on_restore;
void insert_update_stack(expr* e);
bool insert_update(expr* e);
double lookahead(expr* e, bvect const& new_value);
void restore_lookahead();
/**
* Register e as a bit-vector.
* Return true if not already registered, false if already registered.
*/
bool add_bit_vector(app* e);
sls_valuation* alloc_valuation(app* e);
void add_bit_vector(app* e);
sls::bv_valuation* alloc_valuation(app* e);
bool bval1_basic(app* e) const;
bool bval1_bv(app* e) const;
bool bval1_bv(app* e, bool use_current) const;
bool bval1_tmp(app* e) const;
void fold_oper(bvect& out, app* e, unsigned i, std::function<void(bvect&, bvval const&)> const& f);
/**
* Repair operations
*/
bool try_repair_basic(app* e, unsigned i);
bool try_repair_bv(app * e, unsigned i);
bool try_repair_and_or(app* e, unsigned i);
bool try_repair_not(app* e);
bool try_repair_eq(app* e, unsigned i);
bool try_repair_xor(app* e, unsigned i);
bool try_repair_ite(app* e, unsigned i);
bool try_repair_implies(app* e, unsigned i);
bool try_repair_band(bvect const& e, bvval& a, bvval const& b);
bool try_repair_band(app* t, unsigned i);
bool try_repair_bor(bvect const& e, bvval& a, bvval const& b);
bool try_repair_bor(app* t, unsigned i);
bool try_repair_add(bvect const& e, bvval& a, bvval const& b);
bool try_repair_add(app* t, unsigned i);
bool try_repair_sub(bvect const& e, bvval& a, bvval& b, unsigned i);
bool try_repair_mul(bvect const& e, bvval& a, bvval const& b);
bool try_repair_mul(bvect const& e, bvval& a, bvect const& b);
bool try_repair_bxor(bvect const& e, bvval& a, bvval const& b);
bool try_repair_bxor(app* t, unsigned i);
bool try_repair_bnot(bvect const& e, bvval& a);
bool try_repair_bneg(bvect const& e, bvval& a);
bool try_repair_ule(bool e, bvval& a, bvval const& b);
@ -116,11 +118,14 @@ namespace bv {
bool try_repair_umul_ovfl(bool e, bvval& a, bvval& b, unsigned i);
bool try_repair_zero_ext(bvect const& e, bvval& a);
bool try_repair_sign_ext(bvect const& e, bvval& a);
bool try_repair_concat(bvect const& e, bvval& a, bvval& b, unsigned i);
bool try_repair_concat(app* e, unsigned i);
bool try_repair_extract(bvect const& e, bvval& a, unsigned lo);
bool try_repair_comp(bvect const& e, bvval& a, bvval& b, unsigned i);
bool try_repair_eq(bool is_true, bvval& a, bvval const& b);
void add_p2_1(bvval const& a, bvect& t) const;
bool try_repair_eq(app* e, unsigned i);
bool try_repair_eq_lookahead(app* e);
bool try_repair_int2bv(bvect const& e, expr* arg);
void add_p2_1(bvval const& a, bool use_current, bvect& t) const;
bool add_overflow_on_fixed(bvval const& a, bvect const& t);
bool mul_overflow_on_fixed(bvval const& a, bvect const& t);
@ -130,66 +135,58 @@ namespace bv {
digit_t random_bits();
bool random_bool() { return m_rand() % 2 == 0; }
sls_valuation& wval(app* e, unsigned i) { return wval(e->get_arg(i)); }
sls::bv_valuation& wval(app* e, unsigned i) { return wval(e->get_arg(i)); }
void eval(app* e, sls_valuation& val) const;
void eval(app* e, sls::bv_valuation& val) const;
bvect const& eval_value(app* e) const { return wval(e).eval; }
bvect const& assign_value(app* e) const { return wval(e).bits(); }
/**
* Retrieve evaluation based on immediate children.
*/
bool can_eval1(app* e) const;
void commit_eval(expr* p, app* e);
public:
sls_eval(ast_manager& m);
bv_eval(sls::bv_terms& terms, sls::context& ctx);
void init_eval(expr_ref_vector const& es, std::function<bool(expr*, unsigned)> const& eval);
void init() { m_fix.init(); }
void tighten_range(expr_ref_vector const& es) { m_fix.init(es); }
ptr_vector<expr>& sort_assertions(expr_ref_vector const& es);
void register_term(expr* e);
/**
* Retrieve evaluation based on cache.
* bval - Boolean values
* wval - Word (bit-vector) values
*/
bool bval0(expr* e) const { return m_eval[e->get_id()]; }
*/
sls_valuation& wval(expr* e) const;
sls::bv_valuation& wval(expr* e) const;
void set(expr* e, sls::bv_valuation const& val);
bool is_fixed0(expr* e) const { return m_fixed.get(e->get_id(), false); }
/**
* Retrieve evaluation based on immediate children.
*/
bool bval1(app* e) const;
bool can_eval1(app* e) const;
sls_valuation& eval(app* e) const;
void commit_eval(app* e);
void init_eval(app* e);
sls::bv_valuation& eval(app* e) const;
void set_random(app* e);
bool eval_is_correct(app* e);
bool re_eval_is_correct(app* e);
bool is_uninterpreted(app* e) const;
expr_ref get_value(app* e);
/**
* Override evaluaton.
bool bval0(expr* e) const { return ctx.is_true(e); }
bool bval1(app* e) const;
/*
* Try to invert value of child to repair value assignment of parent.
*/
void set(expr* e, bool b) {
m_eval[e->get_id()] = b;
}
/*
* Try to invert value of child to repair value assignment of parent.
*/
bool try_repair(app* e, unsigned i);
bool repair_down(app* e, unsigned i);
/*
* Propagate repair up to parent
@ -197,8 +194,8 @@ namespace bv {
bool repair_up(expr* e);
std::ostream& display(std::ostream& out, expr_ref_vector const& es);
std::ostream& display(std::ostream& out) const;
std::ostream& display_value(std::ostream& out, expr* e);
std::ostream& display_value(std::ostream& out, expr* e) const;
};
}

2
src/ast/sls/sls_evaluator.h → src/ast/sls/sls_bv_evaluator.h
View file

@ -22,7 +22,7 @@ Notes:
#include "model/model_evaluator.h"
#include "ast/sls/sls_powers.h"
#include "ast/sls/sls_tracker.h"
#include "ast/sls/sls_bv_tracker.h"
class sls_evaluator {
ast_manager & m_manager;

341
src/ast/sls/bv_sls_fixed.cpp → src/ast/sls/sls_bv_fixed.cpp
View file

@ -13,56 +13,52 @@ Author:
#include "ast/ast_pp.h"
#include "ast/ast_ll_pp.h"
#include "ast/sls/bv_sls_fixed.h"
#include "ast/sls/bv_sls_eval.h"
#include "ast/sls/sls_bv_fixed.h"
#include "ast/sls/sls_bv_terms.h"
#include "ast/sls/sls_bv_eval.h"
namespace bv {
namespace sls {
sls_fixed::sls_fixed(sls_eval& ev):
bv_fixed::bv_fixed(bv_eval& ev, bv_terms& terms, sls::context& ctx):
ev(ev),
terms(terms),
m(ev.m),
bv(ev.bv)
bv(ev.bv),
ctx(ctx)
{}
void sls_fixed::init(expr_ref_vector const& es) {
ev.sort_assertions(es);
for (expr* e : ev.m_todo) {
if (!is_app(e))
void bv_fixed::init() {
for (auto e : ctx.subterms())
set_fixed(e);
//ctx.display(verbose_stream());
for (auto lit : ctx.unit_literals()) {
auto a = ctx.atom(lit.var());
if (!a)
continue;
app* a = to_app(e);
ev.m_fixed.setx(a->get_id(), is_fixed1(a), false);
if (a->get_family_id() == basic_family_id)
init_fixed_basic(a);
else if (a->get_family_id() == bv.get_family_id())
init_fixed_bv(a);
else
;
if (is_app(a))
init_range(to_app(a), lit.sign());
ev.m_fixed.setx(a->get_id(), true, false);
}
init_ranges(es);
ev.m_todo.reset();
//ctx.display(verbose_stream());
for (auto e : ctx.subterms())
propagate_range_up(e);
//ctx.display(verbose_stream());
}
void sls_fixed::init_ranges(expr_ref_vector const& es) {
for (expr* e : es) {
bool sign = m.is_not(e, e);
if (is_app(e))
init_range(to_app(e), sign);
}
for (expr* e : ev.m_todo)
propagate_range_up(e);
}
void sls_fixed::propagate_range_up(expr* e) {
void bv_fixed::propagate_range_up(expr* e) {
expr* t, * s;
rational v;
if (bv.is_concat(e, t, s)) {
auto& vals = wval(s);
auto& vals = ev.wval(s);
if (vals.lo() != vals.hi() && (vals.lo() < vals.hi() || vals.hi() == 0))
// lo <= e
add_range(e, vals.lo(), rational::zero(), false);
auto valt = wval(t);
auto valt = ev.wval(t);
if (valt.lo() != valt.hi() && (valt.lo() < valt.hi() || valt.hi() == 0)) {
// (2^|s|) * lo <= e < (2^|s|) * hi
auto p = rational::power_of_two(bv.get_bv_size(s));
@ -70,12 +66,12 @@ namespace bv {
}
}
else if (bv.is_bv_add(e, s, t) && bv.is_numeral(s, v)) {
auto& val = wval(t);
auto& val = ev.wval(t);
if (val.lo() != val.hi())
add_range(e, v + val.lo(), v + val.hi(), false);
}
else if (bv.is_bv_add(e, t, s) && bv.is_numeral(s, v)) {
auto& val = wval(t);
auto& val = ev.wval(t);
if (val.lo() != val.hi())
add_range(e, v + val.lo(), v + val.hi(), false);
}
@ -83,7 +79,7 @@ namespace bv {
// x in [lo, hi[ => -x in [-hi + 1, -lo + 1[
else if (bv.is_bv_mul(e, s, t) && bv.is_numeral(s, v) &&
v + 1 == rational::power_of_two(bv.get_bv_size(e))) {
auto& val = wval(t);
auto& val = ev.wval(t);
if (val.lo() != val.hi())
add_range(e, -val.hi() + 1, - val.lo() + 1, false);
}
@ -91,7 +87,7 @@ namespace bv {
// s <=s t <=> s + K <= t + K, K = 2^{bw-1}
bool sls_fixed::init_range(app* e, bool sign) {
bool bv_fixed::init_range(app* e, bool sign) {
expr* s, * t, * x, * y;
rational a, b;
unsigned idx;
@ -149,7 +145,7 @@ namespace bv {
return true;
}
else if (bv.is_bit2bool(e, s, idx)) {
auto& val = wval(s);
auto& val = ev.wval(s);
val.try_set_bit(idx, !sign);
val.fixed.set(idx, true);
val.tighten_range();
@ -159,17 +155,17 @@ namespace bv {
return false;
}
bool sls_fixed::init_eq(expr* t, rational const& a, bool sign) {
bool bv_fixed::init_eq(expr* t, rational const& a, bool sign) {
unsigned lo, hi;
rational b(0);
// verbose_stream() << mk_bounded_pp(t, m) << " == " << a << "\n";
expr* s = nullptr;
if (sign)
if (sign && true)
// 1 <= t - a
init_range(nullptr, rational(1), t, -a, false);
else
if (!sign)
// t - a <= 0
init_range(t, -a, nullptr, rational::zero(), false);
if (!sign && bv.is_bv_not(t, s)) {
for (unsigned i = 0; i < bv.get_bv_size(s); ++i)
if (!a.get_bit(i))
@ -187,20 +183,21 @@ namespace bv {
}
if (bv.is_extract(t, lo, hi, s)) {
if (hi == lo) {
sign = sign ? a == 1 : a == 0;
auto& val = wval(s);
if (val.try_set_bit(lo, !sign))
val.fixed.set(lo, true);
auto sign1 = sign ? a == 1 : a == 0;
auto& val = ev.wval(s);
if (val.try_set_bit(lo, !sign1))
val.fixed.set(lo, true);
val.tighten_range();
}
else if (!sign) {
auto& val = wval(s);
auto& val = ev.wval(s);
for (unsigned i = lo; i <= hi; ++i)
if (val.try_set_bit(i, a.get_bit(i - lo)))
val.fixed.set(i, true);
val.tighten_range();
// verbose_stream() << lo << " " << hi << " " << val << " := " << a << "\n";
}
}
if (!sign && hi + 1 == bv.get_bv_size(s)) {
// s < 2^lo * (a + 1)
@ -223,7 +220,7 @@ namespace bv {
// a < x + b <=> ! (x + b <= a) <=> x not in [-a, b - a [ <=> x in [b - a, -a [ a != -1
// x + a < x + b <=> ! (x + b <= x + a) <=> x in [-a, -b [ a != b
//
bool sls_fixed::init_range(expr* x, rational const& a, expr* y, rational const& b, bool sign) {
bool bv_fixed::init_range(expr* x, rational const& a, expr* y, rational const& b, bool sign) {
if (!x && !y)
return false;
if (!x)
@ -235,8 +232,8 @@ namespace bv {
return false;
}
bool sls_fixed::add_range(expr* e, rational lo, rational hi, bool sign) {
auto& v = wval(e);
bool bv_fixed::add_range(expr* e, rational lo, rational hi, bool sign) {
auto& v = ev.wval(e);
lo = mod(lo, rational::power_of_two(bv.get_bv_size(e)));
hi = mod(hi, rational::power_of_two(bv.get_bv_size(e)));
if (lo == hi)
@ -262,7 +259,7 @@ namespace bv {
return true;
}
void sls_fixed::get_offset(expr* e, expr*& x, rational& offset) {
void bv_fixed::get_offset(expr* e, expr*& x, rational& offset) {
expr* s, * t;
x = e;
offset = 0;
@ -285,177 +282,173 @@ namespace bv {
x = nullptr;
}
sls_valuation& sls_fixed::wval(expr* e) {
return ev.wval(e);
}
void sls_fixed::init_fixed_basic(app* e) {
if (bv.is_bv(e) && m.is_ite(e)) {
auto& val = wval(e);
auto& val_th = wval(e->get_arg(1));
auto& val_el = wval(e->get_arg(2));
for (unsigned i = 0; i < val.nw; ++i)
val.fixed[i] = val_el.fixed[i] & val_th.fixed[i] & ~(val_el.bits(i) ^ val_th.bits(i));
}
}
void sls_fixed::init_fixed_bv(app* e) {
if (bv.is_bv(e))
set_fixed_bw(e);
}
bool sls_fixed::is_fixed1(app* e) const {
bool bv_fixed::is_fixed1(app* e) const {
if (is_uninterp(e))
return false;
if (e->get_family_id() == basic_family_id)
return is_fixed1_basic(e);
return all_of(*e, [&](expr* arg) { return ev.is_fixed0(arg); });
}
bool sls_fixed::is_fixed1_basic(app* e) const {
switch (e->get_decl_kind()) {
case OP_TRUE:
case OP_FALSE:
return true;
case OP_AND:
return any_of(*e, [&](expr* arg) { return ev.is_fixed0(arg) && !ev.bval0(e); });
case OP_OR:
return any_of(*e, [&](expr* arg) { return ev.is_fixed0(arg) && ev.bval0(e); });
default:
return all_of(*e, [&](expr* arg) { return ev.is_fixed0(arg); });
}
}
void sls_fixed::set_fixed_bw(app* e) {
SASSERT(bv.is_bv(e));
SASSERT(e->get_family_id() == bv.get_fid());
auto& v = ev.wval(e);
if (all_of(*e, [&](expr* arg) { return ev.is_fixed0(arg); })) {
for (unsigned i = 0; i < v.bw; ++i)
v.fixed.set(i, true);
void bv_fixed::set_fixed(expr* _e) {
if (!is_app(_e))
return;
auto e = to_app(_e);
if (e->get_family_id() == bv.get_family_id() && all_of(*e, [&](expr* arg) { return ev.is_fixed0(arg); })) {
if (bv.is_bv(e)) {
auto& v = ev.wval(e);
for (unsigned i = 0; i < v.bw; ++i)
v.fixed.set(i, true);
}
ev.m_fixed.setx(e->get_id(), true, false);
return;
}
if (!bv.is_bv(e))
return;
auto& v = ev.wval(e);
if (m.is_ite(e)) {
auto& val_th = ev.wval(e->get_arg(1));
auto& val_el = ev.wval(e->get_arg(2));
for (unsigned i = 0; i < v.nw; ++i)
v.fixed[i] = val_el.fixed[i] & val_th.fixed[i] & ~(val_el.bits(i) ^ val_th.bits(i));
return;
}
if (e->get_family_id() != bv.get_fid())
return;
switch (e->get_decl_kind()) {
case OP_BAND: {
auto& a = wval(e->get_arg(0));
auto& b = wval(e->get_arg(1));
// (a.fixed & b.fixed) | (a.fixed & ~a.bits) | (b.fixed & ~b.bits)
for (unsigned i = 0; i < a.nw; ++i)
v.fixed[i] = (a.fixed[i] & b.fixed[i]) | (a.fixed[i] & ~a.bits(i)) | (b.fixed[i] & ~b.bits(i));
if (e->get_num_args() == 2) {
auto& a = ev.wval(e->get_arg(0));
auto& b = ev.wval(e->get_arg(1));
// (a.fixed & b.fixed) | (a.fixed & ~a.bits) | (b.fixed & ~b.bits)
for (unsigned i = 0; i < a.nw; ++i)
v.fixed[i] = (a.fixed[i] & b.fixed[i]) | (a.fixed[i] & ~a.bits(i)) | (b.fixed[i] & ~b.bits(i));
}
break;
}
case OP_BOR: {
auto& a = wval(e->get_arg(0));
auto& b = wval(e->get_arg(1));
// (a.fixed & b.fixed) | (a.fixed & a.bits) | (b.fixed & b.bits)
for (unsigned i = 0; i < a.nw; ++i)
v.fixed[i] = (a.fixed[i] & b.fixed[i]) | (a.fixed[i] & a.bits(i)) | (b.fixed[i] & b.bits(i));
if (e->get_num_args() == 2) {
auto& a = ev.wval(e->get_arg(0));
auto& b = ev.wval(e->get_arg(1));
// (a.fixed & b.fixed) | (a.fixed & a.bits) | (b.fixed & b.bits)
for (unsigned i = 0; i < a.nw; ++i)
v.fixed[i] = (a.fixed[i] & b.fixed[i]) | (a.fixed[i] & a.bits(i)) | (b.fixed[i] & b.bits(i));
}
break;
}
case OP_BXOR: {
auto& a = wval(e->get_arg(0));
auto& b = wval(e->get_arg(1));
for (unsigned i = 0; i < a.nw; ++i)
v.fixed[i] = a.fixed[i] & b.fixed[i];
if (e->get_num_args() == 2) {
auto& a = ev.wval(e->get_arg(0));
auto& b = ev.wval(e->get_arg(1));
for (unsigned i = 0; i < a.nw; ++i)
v.fixed[i] = a.fixed[i] & b.fixed[i];
}
break;
}
case OP_BNOT: {
auto& a = wval(e->get_arg(0));
auto& a = ev.wval(e->get_arg(0));
for (unsigned i = 0; i < a.nw; ++i)
v.fixed[i] = a.fixed[i];
break;
}
case OP_BADD: {
auto& a = wval(e->get_arg(0));
auto& b = wval(e->get_arg(1));
bool pfixed = true;
for (unsigned i = 0; i < v.bw; ++i) {
if (pfixed && a.fixed.get(i) && b.fixed.get(i))
v.fixed.set(i, true);
else if (!pfixed && a.fixed.get(i) && b.fixed.get(i) &&
!a.get_bit(i) && !b.get_bit(i)) {
pfixed = true;
v.fixed.set(i, false);
}
else {
pfixed = false;
v.fixed.set(i, false);
for (unsigned j = 0; pfixed && j < e->get_num_args(); ++j) {
auto& a = ev.wval(e->get_arg(j));
pfixed &= a.fixed.get(i);
}
v.fixed.set(i, pfixed);
}
break;
}
case OP_BMUL: {
auto& a = wval(e->get_arg(0));
auto& b = wval(e->get_arg(1));
unsigned j = 0, k = 0, zj = 0, zk = 0, hzj = 0, hzk = 0;
// i'th bit depends on bits j + k = i
// if the first j, resp k bits are 0, the bits j + k are 0
for (; j < v.bw; ++j)
if (!a.fixed.get(j))
break;
for (; k < v.bw; ++k)
if (!b.fixed.get(k))
break;
for (; zj < v.bw; ++zj)
if (!a.fixed.get(zj) || a.get_bit(zj))
break;
for (; zk < v.bw; ++zk)
if (!b.fixed.get(zk) || b.get_bit(zk))
break;
for (; hzj < v.bw; ++hzj)
if (!a.fixed.get(v.bw - hzj - 1) || a.get_bit(v.bw - hzj - 1))
break;
for (; hzk < v.bw; ++hzk)
if (!b.fixed.get(v.bw - hzk - 1) || b.get_bit(v.bw - hzk - 1))
break;
if (e->get_num_args() == 2) {
SASSERT(e->get_num_args() == 2);
auto& a = ev.wval(e->get_arg(0));
auto& b = ev.wval(e->get_arg(1));
unsigned j = 0, k = 0, zj = 0, zk = 0, hzj = 0, hzk = 0;
// i'th bit depends on bits j + k = i
// if the first j, resp k bits are 0, the bits j + k are 0
for (; j < v.bw; ++j)
if (!a.fixed.get(j))
break;
for (; k < v.bw; ++k)
if (!b.fixed.get(k))
break;
for (; zj < v.bw; ++zj)
if (!a.fixed.get(zj) || a.get_bit(zj))
break;
for (; zk < v.bw; ++zk)
if (!b.fixed.get(zk) || b.get_bit(zk))
break;
for (; hzj < v.bw; ++hzj)
if (!a.fixed.get(v.bw - hzj - 1) || a.get_bit(v.bw - hzj - 1))
break;
for (; hzk < v.bw; ++hzk)
if (!b.fixed.get(v.bw - hzk - 1) || b.get_bit(v.bw - hzk - 1))
break;
if (j > 0 && k > 0) {
for (unsigned i = 0; i < std::min(k, j); ++i) {
SASSERT(!v.get_bit(i));
v.fixed.set(i, true);
if (j > 0 && k > 0) {
for (unsigned i = 0; i < std::min(k, j); ++i) {
SASSERT(!v.get_bit(i));
v.fixed.set(i, true);
}
}
// lower zj + jk bits are 0
if (zk > 0 || zj > 0) {
for (unsigned i = 0; i < zk + zj; ++i) {
SASSERT(!v.get_bit(i));
v.fixed.set(i, true);
}
}
// upper bits are 0, if enough high order bits of a, b are 0.
// TODO - buggy
if (false && hzj < v.bw && hzk < v.bw && hzj + hzk > v.bw) {
hzj = v.bw - hzj;
hzk = v.bw - hzk;
for (unsigned i = hzj + hzk - 1; i < v.bw; ++i) {
SASSERT(!v.get_bit(i));
v.fixed.set(i, true);
}
}
}
// lower zj + jk bits are 0
if (zk > 0 || zj > 0) {
for (unsigned i = 0; i < zk + zj; ++i) {
SASSERT(!v.get_bit(i));
v.fixed.set(i, true);
else {
bool pfixed = true;
for (unsigned i = 0; i < v.bw; ++i) {
for (unsigned j = 0; pfixed && j < e->get_num_args(); ++j) {
auto& a = ev.wval(e->get_arg(j));
pfixed &= a.fixed.get(i);
}
v.fixed.set(i, pfixed);
}
}
// upper bits are 0, if enough high order bits of a, b are 0.
// TODO - buggy
if (false && hzj < v.bw && hzk < v.bw && hzj + hzk > v.bw) {
hzj = v.bw - hzj;
hzk = v.bw - hzk;
for (unsigned i = hzj + hzk - 1; i < v.bw; ++i) {
SASSERT(!v.get_bit(i));
v.fixed.set(i, true);
}
}
break;
}
case OP_CONCAT: {
auto& a = wval(e->get_arg(0));
auto& b = wval(e->get_arg(1));
for (unsigned i = 0; i < b.bw; ++i)
v.fixed.set(i, b.fixed.get(i));
for (unsigned i = 0; i < a.bw; ++i)
v.fixed.set(i + b.bw, a.fixed.get(i));
unsigned bw = 0;
for (unsigned i = e->get_num_args(); i-- > 0; ) {
auto& a = ev.wval(e->get_arg(i));
for (unsigned j = 0; j < a.bw; ++j)
v.fixed.set(bw + j, a.fixed.get(j));
bw += a.bw;
}
break;
}
case OP_EXTRACT: {
expr* child;
unsigned lo, hi;
VERIFY(bv.is_extract(e, lo, hi, child));
auto& a = wval(child);
auto& a = ev.wval(child);
for (unsigned i = lo; i <= hi; ++i)
v.fixed.set(i - lo, a.fixed.get(i));
break;
}
case OP_BNEG: {
auto& a = wval(e->get_arg(0));
auto& a = ev.wval(e->get_arg(0));
bool pfixed = true;
for (unsigned i = 0; i < v.bw; ++i) {
if (pfixed && a.fixed.get(i))

34
src/ast/sls/bv_sls_fixed.h → src/ast/sls/sls_bv_fixed.h
View file

@ -17,19 +17,23 @@ Author:
#pragma once
#include "ast/ast.h"
#include "ast/sls/sls_valuation.h"
#include "ast/sls/sls_bv_valuation.h"
#include "ast/sls/sls_context.h"
#include "ast/bv_decl_plugin.h"
namespace bv {
class sls_eval;
namespace sls {
class bv_terms;
class bv_eval;
class sls_fixed {
sls_eval& ev;
ast_manager& m;
bv_util& bv;
class bv_fixed {
bv_eval& ev;
bv_terms& terms;
ast_manager& m;
bv_util& bv;
sls::context& ctx;
void init_ranges(expr_ref_vector const& es);
bool init_range(app* e, bool sign);
void propagate_range_up(expr* e);
bool init_range(expr* x, rational const& a, expr* y, rational const& b, bool sign);
@ -37,19 +41,11 @@ namespace bv {
bool init_eq(expr* e, rational const& v, bool sign);
bool add_range(expr* e, rational lo, rational hi, bool sign);
void init_fixed_basic(app* e);
void init_fixed_bv(app* e);
bool is_fixed1(app* e) const;
bool is_fixed1_basic(app* e) const;
void set_fixed_bw(app* e);
sls_valuation& wval(expr* e);
void set_fixed(expr* e);
public:
sls_fixed(sls_eval& ev);
void init(expr_ref_vector const& es);
bv_fixed(bv_eval& ev, bv_terms& terms, sls::context& ctx);
void init();
};
}

206
src/ast/sls/sls_bv_plugin.cpp Normal file
View file

@ -0,0 +1,206 @@
/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
sls_bv_plugin.cpp
Abstract:
Theory plugin for bit-vector local search
Author:
Nikolaj Bjorner (nbjorner) 2024-07-06
--*/
#include "ast/sls/sls_bv_plugin.h"
#include "ast/ast_ll_pp.h"
#include "ast/ast_pp.h"
namespace sls {
bv_plugin::bv_plugin(context& ctx):
plugin(ctx),
bv(m),
m_terms(ctx),
m_eval(m_terms, ctx) {
m_fid = bv.get_family_id();
}
void bv_plugin::register_term(expr* e) {
m_terms.register_term(e);
m_eval.register_term(e);
}
expr_ref bv_plugin::get_value(expr* e) {
SASSERT(bv.is_bv(e));
auto const & val = m_eval.wval(e);
return expr_ref(bv.mk_numeral(val.get_value(), e->get_sort()), m);
}
bool bv_plugin::is_bv_predicate(expr* e) {
if (!e || !is_app(e))
return false;
auto a = to_app(e);
if (a->get_family_id() == bv.get_family_id())
return true;
if (m.is_eq(e) && bv.is_bv(a->get_arg(0)))
return true;
return false;
}
void bv_plugin::propagate_literal(sat::literal lit) {
SASSERT(ctx.is_true(lit));
auto e = ctx.atom(lit.var());
if (!is_bv_predicate(e))
return;
auto a = to_app(e);
if (!m_eval.eval_is_correct(a)) {
IF_VERBOSE(20, verbose_stream() << "repair " << lit << " " << mk_bounded_pp(e, m) << "\n");
ctx.new_value_eh(e);
}
}
bool bv_plugin::propagate() {
auto& axioms = m_terms.axioms();
if (!axioms.empty()) {
for (auto* e : axioms)
ctx.add_constraint(e);
axioms.reset();
return true;
}
return false;
}
void bv_plugin::initialize() {
if (!m_initialized) {
m_eval.init();
m_initialized = true;
}
}
void bv_plugin::init_bool_var_assignment(sat::bool_var v) {
auto a = ctx.atom(v);
if (!a || !is_app(a))
return;
if (to_app(a)->get_family_id() != bv.get_family_id())
return;
bool is_true = m_eval.bval1(to_app(a));
if (is_true != ctx.is_true(v))
ctx.flip(v);
}
bool bv_plugin::is_sat() {
bool is_sat = true;
for (auto t : ctx.subterms())
if (is_app(t) && bv.is_bv(t) && to_app(t)->get_family_id() == bv.get_fid() && !m_eval.eval_is_correct(to_app(t))) {
ctx.new_value_eh(t);
is_sat = false;
}
return is_sat;
}
std::ostream& bv_plugin::display(std::ostream& out) const {
return m_eval.display(out);
}
bool bv_plugin::set_value(expr* e, expr* v) {
if (!bv.is_bv(e))
return false;
rational val;
VERIFY(bv.is_numeral(v, val));
auto& w = m_eval.eval(to_app(e));
w.set_value(w.eval, val);
return w.commit_eval();
}
bool bv_plugin::repair_down(app* e) {
unsigned n = e->get_num_args();
bool status = true;
if (n == 0 || m_eval.is_uninterpreted(e) || m_eval.eval_is_correct(e))
goto done;
if (n == 2) {
auto d1 = get_depth(e->get_arg(0));
auto d2 = get_depth(e->get_arg(1));
unsigned s = ctx.rand(d1 + d2 + 2);
if (s <= d1 && m_eval.repair_down(e, 0))
goto done;
if (m_eval.repair_down(e, 1))
goto done;
if (m_eval.repair_down(e, 0))
goto done;
}
else {
unsigned s = ctx.rand(n);
for (unsigned i = 0; i < n; ++i) {
auto j = (i + s) % n;
if (m_eval.repair_down(e, j))
goto done;
}
}
status = false;
done:
log(e, false, status);
return status;
}
void bv_plugin::repair_up(app* e) {
if (m_eval.repair_up(e)) {
if (!m_eval.eval_is_correct(e)) {
verbose_stream() << "Incorrect eval #" << e->get_id() << " " << mk_bounded_pp(e, m) << "\n";
}
log(e, true, true);
SASSERT(m_eval.eval_is_correct(e));
if (m.is_bool(e)) {
if (ctx.is_true(e) != m_eval.bval1(e))
ctx.flip(ctx.atom2bool_var(e));
}
}
else if (bv.is_bv(e)) {
log(e, true, false);
IF_VERBOSE(5, verbose_stream() << "repair-up "; trace_repair(true, e));
auto& v = m_eval.wval(e);
m_eval.set_random(e);
ctx.new_value_eh(e);
}
else
log(e, true, false);
}
void bv_plugin::repair_literal(sat::literal lit) {
SASSERT(ctx.is_true(lit));
auto e = ctx.atom(lit.var());
if (!is_bv_predicate(e))
return;
auto a = to_app(e);
if (!m_eval.eval_is_correct(a))
ctx.flip(lit.var());
}
std::ostream& bv_plugin::trace_repair(bool down, expr* e) {
verbose_stream() << (down ? "d #" : "u #")
<< e->get_id() << ": "
<< mk_bounded_pp(e, m, 1) << " ";
return m_eval.display_value(verbose_stream(), e) << "\n";
}
void bv_plugin::trace() {
IF_VERBOSE(2, verbose_stream()
<< "(bvsls :restarts " << m_stats.m_restarts << ")\n");
}
void bv_plugin::log(expr* e, bool up_down, bool success) {
IF_VERBOSE(11, verbose_stream() << mk_bounded_pp(e, m) << " " << (up_down?"u":"d") << " " << (success ? "S" : "F");
if (bv.is_bv(e)) verbose_stream() << " " << m_eval.wval(e);
verbose_stream() << "\n");
}
}

62
src/ast/sls/sls_bv_plugin.h Normal file
View file

@ -0,0 +1,62 @@
/*++
Copyright (c) 2020 Microsoft Corporation
Module Name:
sls_bv_plugin.h
Abstract:
Theory plugin for bit-vector local search
Author:
Nikolaj Bjorner (nbjorner) 2024-07-06
--*/
#pragma once
#include "ast/sls/sls_context.h"
#include "ast/bv_decl_plugin.h"
#include "ast/sls/sls_bv_terms.h"
#include "ast/sls/sls_bv_eval.h"
namespace sls {
class bv_plugin : public plugin {
bv_util bv;
bv_terms m_terms;
bv_eval m_eval;
bv::sls_stats m_stats;
bool m_initialized = false;
void init_bool_var_assignment(sat::bool_var v);
std::ostream& trace_repair(bool down, expr* e);
void trace();
bool can_propagate();
bool is_bv_predicate(expr* e);
void log(expr* e, bool up_down, bool success);
public:
bv_plugin(context& ctx);
~bv_plugin() override {}
void register_term(expr* e) override;
expr_ref get_value(expr* e) override;
void initialize() override;
void propagate_literal(sat::literal lit) override;
bool propagate() override;
bool repair_down(app* e) override;
void repair_up(app* e) override;
void repair_literal(sat::literal lit) override;
bool is_sat() override;
void on_rescale() override {}
void on_restart() override {}
std::ostream& display(std::ostream& out) const override;
bool set_value(expr* e, expr* v) override;
void collect_statistics(statistics& st) const override {}
void reset_statistics() override {}
};
}

143
src/ast/sls/sls_bv_terms.cpp Normal file
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@ -0,0 +1,143 @@
/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
bv_sls_terms.cpp
Abstract:
normalize bit-vector expressions to use only binary operators.
Author:
Nikolaj Bjorner (nbjorner) 2024-02-07
--*/
#include "ast/ast_ll_pp.h"
#include "ast/sls/sls_bv_terms.h"
#include "ast/rewriter/bool_rewriter.h"
#include "ast/rewriter/bv_rewriter.h"
namespace sls {
bv_terms::bv_terms(sls::context& ctx):
m(ctx.get_manager()),
bv(m),
m_axioms(m) {}
void bv_terms::register_term(expr* e) {
auto r = ensure_binary(e);
if (r != e)
m_axioms.push_back(m.mk_eq(e, r));
register_uninterp(e);
}
expr_ref bv_terms::ensure_binary(expr* e) {
expr* x, * y;
expr_ref r(m);
if (bv.is_bv_sdiv(e, x, y) || bv.is_bv_sdiv0(e, x, y) || bv.is_bv_sdivi(e, x, y))
r = mk_sdiv(x, y);
else if (bv.is_bv_smod(e, x, y) || bv.is_bv_smod0(e, x, y) || bv.is_bv_smodi(e, x, y))
r = mk_smod(x, y);
else if (bv.is_bv_srem(e, x, y) || bv.is_bv_srem0(e, x, y) || bv.is_bv_sremi(e, x, y))
r = mk_srem(x, y);
else
r = e;
return r;
}
expr_ref bv_terms::mk_sdiv(expr* x, expr* y) {
// d = udiv(abs(x), abs(y))
// y = 0, x >= 0 -> -1
// y = 0, x < 0 -> 1
// x = 0, y != 0 -> 0
// x > 0, y < 0 -> -d
// x < 0, y > 0 -> -d
// x > 0, y > 0 -> d
// x < 0, y < 0 -> d
bool_rewriter br(m);
bv_rewriter bvr(m);
unsigned sz = bv.get_bv_size(x);
rational N = rational::power_of_two(sz);
expr_ref z(bv.mk_zero(sz), m);
expr_ref o(bv.mk_one(sz), m);
expr_ref n1(bv.mk_numeral(N - 1, sz), m);
expr_ref signx = bvr.mk_ule(bv.mk_numeral(N / 2, sz), x);
expr_ref signy = bvr.mk_ule(bv.mk_numeral(N / 2, sz), y);
expr_ref absx = br.mk_ite(signx, bvr.mk_bv_neg(x), x);
expr_ref absy = br.mk_ite(signy, bvr.mk_bv_neg(y), y);
expr_ref d = expr_ref(bv.mk_bv_udiv(absx, absy), m);
expr_ref r = br.mk_ite(br.mk_eq(signx, signy), d, bvr.mk_bv_neg(d));
r = br.mk_ite(br.mk_eq(z, y),
br.mk_ite(signx, o, n1),
br.mk_ite(br.mk_eq(x, z), z, r));
return r;
}
expr_ref bv_terms::mk_smod(expr* x, expr* y) {
// u := umod(abs(x), abs(y))
// u = 0 -> 0
// y = 0 -> x
// x < 0, y < 0 -> -u
// x < 0, y >= 0 -> y - u
// x >= 0, y < 0 -> y + u
// x >= 0, y >= 0 -> u
bool_rewriter br(m);
bv_rewriter bvr(m);
unsigned sz = bv.get_bv_size(x);
expr_ref z(bv.mk_zero(sz), m);
expr_ref abs_x = br.mk_ite(bvr.mk_sle(z, x), x, bvr.mk_bv_neg(x));
expr_ref abs_y = br.mk_ite(bvr.mk_sle(z, y), y, bvr.mk_bv_neg(y));
expr_ref u = bvr.mk_bv_urem(abs_x, abs_y);
expr_ref r(m);
r = br.mk_ite(br.mk_eq(u, z), z,
br.mk_ite(br.mk_eq(y, z), x,
br.mk_ite(br.mk_and(bvr.mk_sle(z, x), bvr.mk_sle(z, x)), u,
br.mk_ite(bvr.mk_sle(z, x), bvr.mk_bv_add(y, u),
br.mk_ite(bv.mk_sle(z, y), bvr.mk_bv_sub(y, u), bvr.mk_bv_neg(u))))));
return r;
}
expr_ref bv_terms::mk_srem(expr* x, expr* y) {
// y = 0 -> x
// else x - sdiv(x, y) * y
expr_ref r(m);
bool_rewriter br(m);
bv_rewriter bvr(m);
expr_ref z(bv.mk_zero(bv.get_bv_size(x)), m);
r = br.mk_ite(br.mk_eq(y, z), x, bvr.mk_bv_sub(x, bvr.mk_bv_mul(y, mk_sdiv(x, y))));
return r;
}
void bv_terms::register_uninterp(expr* e) {
if (!m.is_bool(e))
return;
expr* x, *y;
if (m.is_eq(e, x, y) && bv.is_bv(x))
;
else if (is_app(e) && to_app(e)->get_family_id() == bv.get_fid())
;
else
return;
m_uninterp_occurs.reserve(e->get_id() + 1);
auto& occs = m_uninterp_occurs[e->get_id()];
ptr_vector<expr> todo;
todo.append(to_app(e)->get_num_args(), to_app(e)->get_args());
expr_mark marked;
for (unsigned i = 0; i < todo.size(); ++i) {
e = todo[i];
if (marked.is_marked(e))
continue;
marked.mark(e);
if (is_app(e) && to_app(e)->get_family_id() == bv.get_fid()) {
for (expr* arg : *to_app(e))
todo.push_back(arg);
}
else if (bv.is_bv(e))
occs.push_back(e);
}
}
}

54
src/ast/sls/sls_bv_terms.h Normal file
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@ -0,0 +1,54 @@
/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
bv_sls_terms.h
Abstract:
A Stochastic Local Search (SLS) engine
Author:
Nikolaj Bjorner (nbjorner) 2024-02-07
--*/
#pragma once
#include "util/lbool.h"
#include "util/scoped_ptr_vector.h"
#include "util/uint_set.h"
#include "ast/ast.h"
#include "ast/bv_decl_plugin.h"
#include "ast/sls/sls_stats.h"
#include "ast/sls/sls_powers.h"
#include "ast/sls/sls_bv_valuation.h"
#include "ast/sls/sls_context.h"
namespace sls {
class bv_terms {
ast_manager& m;
bv_util bv;
expr_ref_vector m_axioms;
vector<ptr_vector<expr>> m_uninterp_occurs;
expr_ref ensure_binary(expr* e);
expr_ref mk_sdiv(expr* x, expr* y);
expr_ref mk_smod(expr* x, expr* y);
expr_ref mk_srem(expr* x, expr* y);
void register_uninterp(expr* e);
public:
bv_terms(sls::context& ctx);
void register_term(expr* e);
expr_ref_vector& axioms() { return m_axioms; }
ptr_vector<expr> const& uninterp_occurs(expr* e) { m_uninterp_occurs.reserve(e->get_id() + 1); return m_uninterp_occurs[e->get_id()]; }
};
}

0
src/ast/sls/sls_tracker.h → src/ast/sls/sls_bv_tracker.h
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318
src/ast/sls/sls_valuation.cpp → src/ast/sls/sls_bv_valuation.cpp
View file

@ -18,9 +18,9 @@ Author:
--*/
#include "ast/sls/sls_valuation.h"
#include "ast/sls/sls_bv_valuation.h"
namespace bv {
namespace sls {
void bvect::set_bw(unsigned bw) {
this->bw = bw;
@ -138,6 +138,7 @@ namespace bv {
set_bw(a.bw);
SASSERT(a.bw == b.bw);
unsigned shift = b.to_nat(b.bw);
if (shift == 0)
a.copy_to(a.nw, *this);
else if (shift >= a.bw)
@ -148,7 +149,7 @@ namespace bv {
return *this;
}
sls_valuation::sls_valuation(unsigned bw) {
bv_valuation::bv_valuation(unsigned bw) {
set_bw(bw);
m_lo.set_bw(bw);
m_hi.set_bw(bw);
@ -162,7 +163,7 @@ namespace bv {
fixed[nw - 1] = ~mask;
}
void sls_valuation::set_bw(unsigned b) {
void bv_valuation::set_bw(unsigned b) {
bw = b;
nw = (bw + sizeof(digit_t) * 8 - 1) / (8 * sizeof(digit_t));
mask = (1 << (bw % (8 * sizeof(digit_t)))) - 1;
@ -170,7 +171,7 @@ namespace bv {
mask = ~(digit_t)0;
}
bool sls_valuation::commit_eval() {
bool bv_valuation::commit_eval() {
for (unsigned i = 0; i < nw; ++i)
if (0 != (fixed[i] & (m_bits[i] ^ eval[i])))
return false;
@ -180,11 +181,12 @@ namespace bv {
for (unsigned i = 0; i < nw; ++i)
m_bits[i] = eval[i];
SASSERT(well_formed());
return true;
}
bool sls_valuation::in_range(bvect const& bits) const {
bool bv_valuation::in_range(bvect const& bits) const {
mpn_manager m;
auto c = m.compare(m_lo.data(), nw, m_hi.data(), nw);
SASSERT(!has_overflow(bits));
@ -207,7 +209,7 @@ namespace bv {
// largest dst <= src and dst is feasible
//
bool sls_valuation::get_at_most(bvect const& src, bvect& dst) const {
bool bv_valuation::get_at_most(bvect const& src, bvect& dst) const {
SASSERT(!has_overflow(src));
src.copy_to(nw, dst);
sup_feasible(dst);
@ -227,7 +229,7 @@ namespace bv {
//
// smallest dst >= src and dst is feasible with respect to this.
bool sls_valuation::get_at_least(bvect const& src, bvect& dst) const {
bool bv_valuation::get_at_least(bvect const& src, bvect& dst) const {
SASSERT(!has_overflow(src));
src.copy_to(nw, dst);
dst.set_bw(bw);
@ -244,34 +246,38 @@ namespace bv {
return true;
}
bool sls_valuation::set_random_at_most(bvect const& src, random_gen& r) {
bool bv_valuation::set_random_at_most(bvect const& src, random_gen& r) {
m_tmp.set_bw(bw);
//verbose_stream() << "set_random_at_most " << src << "\n";
if (!get_at_most(src, m_tmp))
return false;
if (is_zero(m_tmp) || (0 != r(10)))
return try_set(m_tmp);
if (is_zero(m_tmp) && (0 != r(2)))
return try_set(m_tmp) && m_tmp <= src;
// random value below tmp
set_random_below(m_tmp, r);
//verbose_stream() << "can set " << m_tmp << " " << can_set(m_tmp) << "\n";
return (can_set(m_tmp) || get_at_most(src, m_tmp)) && try_set(m_tmp);
return (can_set(m_tmp) || get_at_most(src, m_tmp)) && m_tmp <= src && try_set(m_tmp);
}
bool sls_valuation::set_random_at_least(bvect const& src, random_gen& r) {
bool bv_valuation::set_random_at_least(bvect const& src, random_gen& r) {
m_tmp.set_bw(bw);
if (!get_at_least(src, m_tmp))
return false;
if (is_ones(m_tmp) || (0 != r(10)))
if (is_ones(m_tmp) && (0 != r(10)))
return try_set(m_tmp);
// random value at least tmp
set_random_above(m_tmp, r);
return (can_set(m_tmp) || get_at_least(src, m_tmp)) && try_set(m_tmp);
return (can_set(m_tmp) || get_at_least(src, m_tmp)) && src <= m_tmp && try_set(m_tmp);
}
bool sls_valuation::set_random_in_range(bvect const& lo, bvect const& hi, random_gen& r) {
bool bv_valuation::set_random_in_range(bvect const& lo, bvect const& hi, random_gen& r) {
bvect& tmp = m_tmp;
if (0 == r(2)) {
if (!get_at_least(lo, tmp))
@ -279,14 +285,10 @@ namespace bv {
SASSERT(in_range(tmp));
if (hi < tmp)
return false;
if (is_ones(tmp) || (0 == r() % 2))
return try_set(tmp);
set_random_above(tmp, r);
round_down(tmp, [&](bvect const& t) { return hi >= t && in_range(t); });
if (in_range(tmp) && lo <= tmp && hi >= tmp)
return try_set(tmp);
return get_at_least(lo, tmp) && hi >= tmp && try_set(tmp);
if (in_range(tmp) || get_at_least(lo, tmp))
return lo <= tmp && tmp <= hi && try_set(tmp);
}
else {
if (!get_at_most(hi, tmp))
@ -294,37 +296,35 @@ namespace bv {
SASSERT(in_range(tmp));
if (lo > tmp)
return false;
if (is_zero(tmp) || (0 == r() % 2))
return try_set(tmp);
set_random_below(tmp, r);
round_up(tmp, [&](bvect const& t) { return lo <= t && in_range(t); });
if (in_range(tmp) && lo <= tmp && hi >= tmp)
return try_set(tmp);
return get_at_most(hi, tmp) && lo <= tmp && try_set(tmp);
if (in_range(tmp) || get_at_most(hi, tmp))
return lo <= tmp && tmp <= hi && try_set(tmp);
}
return false;
}
void sls_valuation::round_down(bvect& dst, std::function<bool(bvect const&)> const& is_feasible) {
void bv_valuation::round_down(bvect& dst, std::function<bool(bvect const&)> const& is_feasible) {
for (unsigned i = bw; !is_feasible(dst) && i-- > 0; )
if (!fixed.get(i) && dst.get(i))
dst.set(i, false);
repair_sign_bits(dst);
}
void sls_valuation::round_up(bvect& dst, std::function<bool(bvect const&)> const& is_feasible) {
void bv_valuation::round_up(bvect& dst, std::function<bool(bvect const&)> const& is_feasible) {
for (unsigned i = 0; !is_feasible(dst) && i < bw; ++i)
if (!fixed.get(i) && !dst.get(i))
dst.set(i, true);
repair_sign_bits(dst);
}
void sls_valuation::set_random_above(bvect& dst, random_gen& r) {
void bv_valuation::set_random_above(bvect& dst, random_gen& r) {
for (unsigned i = 0; i < nw; ++i)
dst[i] = dst[i] | (random_bits(r) & ~fixed[i]);
repair_sign_bits(dst);
}
void sls_valuation::set_random_below(bvect& dst, random_gen& r) {
void bv_valuation::set_random_below(bvect& dst, random_gen& r) {
if (is_zero(dst))
return;
unsigned n = 0, idx = UINT_MAX;
@ -341,7 +341,7 @@ namespace bv {
repair_sign_bits(dst);
}
bool sls_valuation::set_repair(bool try_down, bvect& dst) {
bool bv_valuation::set_repair(bool try_down, bvect& dst) {
for (unsigned i = 0; i < nw; ++i)
dst[i] = (~fixed[i] & dst[i]) | (fixed[i] & m_bits[i]);
clear_overflow_bits(dst);
@ -358,7 +358,7 @@ namespace bv {
dst.set(i, false);
for (unsigned i = 0; i < bw && dst < m_lo && !in_range(dst); ++i)
if (!fixed.get(i) && !dst.get(i))
dst.set(i, true);
dst.set(i, true);
}
else {
for (unsigned i = 0; !in_range(dst) && i < bw; ++i)
@ -377,7 +377,7 @@ namespace bv {
return repaired;
}
void sls_valuation::min_feasible(bvect& out) const {
void bv_valuation::min_feasible(bvect& out) const {
if (m_lo < m_hi)
m_lo.copy_to(nw, out);
else {
@ -388,7 +388,7 @@ namespace bv {
SASSERT(!has_overflow(out));
}
void sls_valuation::max_feasible(bvect& out) const {
void bv_valuation::max_feasible(bvect& out) const {
if (m_lo < m_hi) {
m_hi.copy_to(nw, out);
sub1(out);
@ -401,7 +401,7 @@ namespace bv {
SASSERT(!has_overflow(out));
}
unsigned sls_valuation::msb(bvect const& src) const {
unsigned bv_valuation::msb(bvect const& src) const {
SASSERT(!has_overflow(src));
for (unsigned i = nw; i-- > 0; )
if (src[i] != 0)
@ -409,7 +409,7 @@ namespace bv {
return bw;
}
unsigned sls_valuation::clz(bvect const& src) const {
unsigned bv_valuation::clz(bvect const& src) const {
SASSERT(!has_overflow(src));
unsigned i = bw;
for (; i-- > 0; )
@ -419,36 +419,64 @@ namespace bv {
}
void sls_valuation::set_value(bvect& bits, rational const& n) {
void bv_valuation::set_value(bvect& bits, rational const& n) {
for (unsigned i = 0; i < bw; ++i)
bits.set(i, n.get_bit(i));
clear_overflow_bits(bits);
}
void sls_valuation::get(bvect& dst) const {
void bv_valuation::get(bvect& dst) const {
m_bits.copy_to(nw, dst);
}
digit_t sls_valuation::random_bits(random_gen& rand) {
digit_t bv_valuation::random_bits(random_gen& rand) {
digit_t r = 0;
for (digit_t i = 0; i < sizeof(digit_t); ++i)
r ^= rand() << (8 * i);
return r;
}
void sls_valuation::get_variant(bvect& dst, random_gen& r) const {
void bv_valuation::get_variant(bvect& dst, random_gen& r) const {
for (unsigned i = 0; i < nw; ++i)
dst[i] = (random_bits(r) & ~fixed[i]) | (fixed[i] & m_bits[i]);
repair_sign_bits(dst);
clear_overflow_bits(dst);
}
bool sls_valuation::set_random(random_gen& r) {
bool bv_valuation::set_random(random_gen& r) {
get_variant(m_tmp, r);
return set_repair(r(2) == 0, m_tmp);
repair_sign_bits(m_tmp);
if (in_range(m_tmp)) {
set(eval, m_tmp);
return true;
}
for (unsigned i = 0; i < nw; ++i)
m_tmp[i] = random_bits(r);
clear_overflow_bits(m_tmp);
// find a random offset within [lo, hi[
SASSERT(m_lo != m_hi);
set_sub(eval, m_hi, m_lo);
for (unsigned i = bw; i-- > 0 && m_tmp >= eval; )
m_tmp.set(i, false);
// set eval back to m_bits. It was garbage.
set(eval, m_bits);
// tmp := lo + tmp is within [lo, hi[
set_add(m_tmp, m_tmp, m_lo);
// respect fixed bits
for (unsigned i = 0; i < bw; ++i)
if (fixed.get(i))
m_tmp.set(i, m_bits.get(i));
// decrease tmp until it is in range again
for (unsigned i = bw; i-- > 0 && !in_range(m_tmp); )
if (!fixed.get(i))
m_tmp.set(i, false);
repair_sign_bits(m_tmp);
return try_set(m_tmp);
}
void sls_valuation::repair_sign_bits(bvect& dst) const {
void bv_valuation::repair_sign_bits(bvect& dst) const {
if (m_signed_prefix == 0)
return;
bool sign = m_signed_prefix == bw ? dst.get(bw - 1) : dst.get(bw - m_signed_prefix - 1);
@ -474,7 +502,7 @@ namespace bv {
// 0 = (new_bits ^ bits) & fixedf
// also check that new_bits are in range
//
bool sls_valuation::can_set(bvect const& new_bits) const {
bool bv_valuation::can_set(bvect const& new_bits) const {
SASSERT(!has_overflow(new_bits));
for (unsigned i = 0; i < nw; ++i)
if (0 != ((new_bits[i] ^ m_bits[i]) & fixed[i]))
@ -482,28 +510,28 @@ namespace bv {
return in_range(new_bits);
}
unsigned sls_valuation::to_nat(unsigned max_n) const {
unsigned bv_valuation::to_nat(unsigned max_n) const {
bvect const& d = m_bits;
SASSERT(!has_overflow(d));
return d.to_nat(max_n);
}
void sls_valuation::shift_right(bvect& out, unsigned shift) const {
void bv_valuation::shift_right(bvect& out, unsigned shift) const {
SASSERT(shift < bw);
for (unsigned i = 0; i < bw; ++i)
out.set(i, i + shift < bw ? m_bits.get(i + shift) : false);
out.set(i, i + shift < bw ? out.get(i + shift) : false);
SASSERT(well_formed());
}
void sls_valuation::add_range(rational l, rational h) {
void bv_valuation::add_range(rational l, rational h) {
l = mod(l, rational::power_of_two(bw));
h = mod(h, rational::power_of_two(bw));
if (h == l)
return;
// verbose_stream() << *this << " " << l << " " << h << " --> ";
//verbose_stream() << *this << " lo " << l << " hi " << h << " --> ";
if (m_lo == m_hi) {
set_value(m_lo, l);
@ -555,7 +583,7 @@ namespace bv {
// update bits based on ranges
//
unsigned sls_valuation::diff_index(bvect const& a) const {
unsigned bv_valuation::diff_index(bvect const& a) const {
unsigned index = 0;
for (unsigned i = nw; i-- > 0; ) {
auto diff = fixed[i] & (m_bits[i] ^ a[i]);
@ -565,55 +593,87 @@ namespace bv {
return index;
}
void sls_valuation::inf_feasible(bvect& a) const {
// The least a' >= a, such that the fixed bits in bits agree with a'.
// 0 if there is no such a'.
void bv_valuation::inf_feasible(bvect& a) const {
unsigned lo_index = diff_index(a);
if (lo_index != 0) {
lo_index--;
SASSERT(a.get(lo_index) != m_bits.get(lo_index));
SASSERT(fixed.get(lo_index));
for (unsigned i = 0; i <= lo_index; ++i) {
if (!fixed.get(i))
a.set(i, false);
else if (fixed.get(i))
a.set(i, m_bits.get(i));
}
if (!a.get(lo_index)) {
for (unsigned i = lo_index + 1; i < bw; ++i)
if (!fixed.get(i) && !a.get(i)) {
a.set(i, true);
break;
}
}
}
}
void sls_valuation::sup_feasible(bvect& a) const {
unsigned hi_index = diff_index(a);
if (hi_index != 0) {
hi_index--;
SASSERT(a.get(hi_index) != m_bits.get(hi_index));
SASSERT(fixed.get(hi_index));
for (unsigned i = 0; i <= hi_index; ++i) {
if (!fixed.get(i))
a.set(i, true);
else if (fixed.get(i))
a.set(i, m_bits.get(i));
}
if (a.get(hi_index)) {
for (unsigned i = hi_index + 1; i < bw; ++i)
if (!fixed.get(i) && a.get(i)) {
a.set(i, false);
break;
}
}
}
}
void sls_valuation::tighten_range() {
if (m_lo == m_hi)
if (lo_index == 0)
return;
--lo_index;
// decrement a[lo_index:0] maximally
SASSERT(a.get(lo_index) != m_bits.get(lo_index));
SASSERT(fixed.get(lo_index));
for (unsigned i = 0; i <= lo_index; ++i) {
if (!fixed.get(i))
a.set(i, false);
else if (fixed.get(i))
a.set(i, m_bits.get(i));
}
// the previous value of a[lo_index] was 0.
// a[lo_index:0] was incremented, so no need to adjust bits a[:lo_index+1]
if (a.get(lo_index))
return;
// find the minimal increment within a[:lo_index+1]
for (unsigned i = lo_index + 1; i < bw; ++i) {
if (!fixed.get(i) && !a.get(i)) {
a.set(i, true);
return;
}
}
// there is no feasiable value a' >= a, so find the least
// feasiable value a' >= 0.
for (unsigned i = 0; i < bw; ++i)
if (!fixed.get(i))
a.set(i, false);
}
// The greatest a' <= a, such that the fixed bits in bits agree with a'.
// the greatest a' <= -1 if there is no such a'.
void bv_valuation::sup_feasible(bvect& a) const {
unsigned hi_index = diff_index(a);
if (hi_index == 0)
return;
--hi_index;
SASSERT(a.get(hi_index) != m_bits.get(hi_index));
SASSERT(fixed.get(hi_index));
// increment a[hi_index:0] maximally
for (unsigned i = 0; i <= hi_index; ++i) {
if (!fixed.get(i))
a.set(i, true);
else if (fixed.get(i))
a.set(i, m_bits.get(i));
}
// If a[hi_index:0] was decremented, then no need to adjust bits a[:hi_index+1]
if (!a.get(hi_index))
return;
// find the minimal decrement within a[:hi_index+1]
for (unsigned i = hi_index + 1; i < bw; ++i) {
if (!fixed.get(i) && a.get(i)) {
a.set(i, false);
return;
}
}
// a[hi_index:0] was incremented, but a[:hi_index+1] cannot be decremented.
// maximize a[:hi_index+1] to model wrap around behavior.
for (unsigned i = hi_index + 1; i < bw; ++i)
if (!fixed.get(i))
a.set(i, true);
}
void bv_valuation::tighten_range() {
// verbose_stream() << "tighten " << m_lo << " " << m_hi << " " << m_bits << "\n";
if (m_lo == m_hi)
return;
inf_feasible(m_lo);
@ -625,59 +685,8 @@ namespace bv {
add1(hi1);
hi1.copy_to(nw, m_hi);
/*
unsigned lo_index = 0, hi_index = 0;
for (unsigned i = nw; i-- > 0; ) {
auto lo_diff = (fixed[i] & (m_bits[i] ^ m_lo[i]));
if (lo_diff != 0 && lo_index == 0)
lo_index = 1 + i * 8 * sizeof(digit_t) + log2(lo_diff);
auto hi_diff = (fixed[i] & (m_bits[i] ^ hi1[i]));
if (hi_diff != 0 && hi_index == 0)
hi_index = 1 + i * 8 * sizeof(digit_t) + log2(hi_diff);
}
if (lo_index != 0) {
lo_index--;
SASSERT(m_lo.get(lo_index) != m_bits.get(lo_index));
SASSERT(fixed.get(lo_index));
for (unsigned i = 0; i <= lo_index; ++i) {
if (!fixed.get(i))
m_lo.set(i, false);
else if (fixed.get(i))
m_lo.set(i, m_bits.get(i));
}
if (!m_bits.get(lo_index)) {
for (unsigned i = lo_index + 1; i < bw; ++i)
if (!fixed.get(i) && !m_lo.get(i)) {
m_lo.set(i, true);
break;
}
}
}
if (hi_index != 0) {
hi_index--;
SASSERT(hi1.get(hi_index) != m_bits.get(hi_index));
SASSERT(fixed.get(hi_index));
for (unsigned i = 0; i <= hi_index; ++i) {
if (!fixed.get(i))
hi1.set(i, true);
else if (fixed.get(i))
hi1.set(i, m_bits.get(i));
}
if (m_bits.get(hi_index)) {
for (unsigned i = hi_index + 1; i < bw; ++i)
if (!fixed.get(i) && hi1.get(i)) {
hi1.set(i, false);
break;
}
}
add1(hi1);
hi1.copy_to(nw, m_hi);
}
*/
if (has_range() && !in_range(m_bits))
m_bits = m_lo;
m_lo.copy_to(nw, m_bits);
if (mod(lo() + 1, rational::power_of_two(bw)) == hi())
for (unsigned i = 0; i < nw; ++i)
@ -687,16 +696,17 @@ namespace bv {
if (hi() < rational::power_of_two(i))
fixed.set(i, true);
// verbose_stream() << "post tighten " << m_lo << " " << m_hi << " " << m_bits << "\n";
SASSERT(well_formed());
}
void sls_valuation::set_sub(bvect& out, bvect const& a, bvect const& b) const {
void bv_valuation::set_sub(bvect& out, bvect const& a, bvect const& b) const {
digit_t c;
mpn_manager().sub(a.data(), nw, b.data(), nw, out.data(), &c);
clear_overflow_bits(out);
}
bool sls_valuation::set_add(bvect& out, bvect const& a, bvect const& b) const {
bool bv_valuation::set_add(bvect& out, bvect const& a, bvect const& b) const {
digit_t c;
mpn_manager().add(a.data(), nw, b.data(), nw, out.data(), nw + 1, &c);
bool ovfl = out[nw] != 0 || has_overflow(out);
@ -704,7 +714,9 @@ namespace bv {
return ovfl;
}
bool sls_valuation::set_mul(bvect& out, bvect const& a, bvect const& b, bool check_overflow) const {
bool bv_valuation::set_mul(bvect& out, bvect const& a, bvect const& b, bool check_overflow) const {
out.reserve(2 * nw);
SASSERT(out.size() >= 2 * nw);
mpn_manager().mul(a.data(), nw, b.data(), nw, out.data());
bool ovfl = false;
if (check_overflow) {
@ -716,7 +728,7 @@ namespace bv {
return ovfl;
}
bool sls_valuation::is_power_of2(bvect const& src) const {
bool bv_valuation::is_power_of2(bvect const& src) const {
unsigned c = 0;
for (unsigned i = 0; i < nw; ++i)
c += get_num_1bits(src[i]);

25
src/ast/sls/sls_valuation.h → src/ast/sls/sls_bv_valuation.h
View file

@ -3,7 +3,7 @@ Copyright (c) 2024 Microsoft Corporation
Module Name:
sls_valuation.h
sls_bv_valuation.h
Abstract:
@ -20,12 +20,10 @@ Author:
#include "util/params.h"
#include "util/scoped_ptr_vector.h"
#include "util/uint_set.h"
#include "ast/ast.h"
#include "ast/sls/sls_stats.h"
#include "ast/sls/sls_powers.h"
#include "ast/bv_decl_plugin.h"
#include "util/mpz.h"
#include "util/rational.h"
namespace bv {
namespace sls {
class bvect : public svector<digit_t> {
public:
@ -106,7 +104,7 @@ namespace bv {
inline bool operator!=(bvect const& a, bvect const& b) { return !(a == b); }
std::ostream& operator<<(std::ostream& out, bvect const& v);
class sls_valuation {
class bv_valuation {
protected:
bvect m_bits;
bvect m_lo, m_hi; // range assignment to bit-vector, as wrap-around interval
@ -124,8 +122,8 @@ namespace bv {
bvect fixed; // bit assignment and don't care bit
bvect eval; // current evaluation
sls_valuation(unsigned bw);
bv_valuation(unsigned bw);
void set_bw(unsigned bw);
void set_signed(unsigned prefix) { m_signed_prefix = prefix; }
@ -134,7 +132,9 @@ namespace bv {
digit_t bits(unsigned i) const { return m_bits[i]; }
bvect const& bits() const { return m_bits; }
bvect const& tmp_bits(bool use_current) const { return use_current ? m_bits : m_tmp; }
bool commit_eval();
bool is_fixed() const { for (unsigned i = bw; i-- > 0; ) if (!fixed.get(i)) return false; return true; }
bool get_bit(unsigned i) const { return m_bits.get(i); }
bool try_set_bit(unsigned i, bool b) {
@ -166,6 +166,9 @@ namespace bv {
bool has_range() const { return m_lo != m_hi; }
void tighten_range();
void save_value() { m_bits.copy_to(nw, m_tmp); }
void restore_value() { m_tmp.copy_to(nw, m_bits); }
void clear_overflow_bits(bvect& bits) const {
SASSERT(nw > 0);
bits[nw - 1] &= mask;
@ -175,7 +178,7 @@ namespace bv {
bool in_range(bvect const& bits) const;
bool can_set(bvect const& bits) const;
bool eq(sls_valuation const& other) const { return eq(other.m_bits); }
bool eq(bv_valuation const& other) const { return eq(other.m_bits); }
bool eq(bvect const& other) const { return other == m_bits; }
bool is_zero() const { return is_zero(m_bits); }
@ -342,6 +345,6 @@ namespace bv {
};
inline std::ostream& operator<<(std::ostream& out, sls_valuation const& v) { return v.display(out); }
inline std::ostream& operator<<(std::ostream& out, bv_valuation const& v) { return v.display(out); }
}

654
src/ast/sls/sls_context.cpp Normal file
View file

@ -0,0 +1,654 @@
/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
smt_sls.cpp
Abstract:
A Stochastic Local Search (SLS) Context.
Author:
Nikolaj Bjorner (nbjorner) 2024-06-24
--*/
#include "ast/sls/sls_context.h"
#include "ast/sls/sls_euf_plugin.h"
#include "ast/sls/sls_arith_plugin.h"
#include "ast/sls/sls_array_plugin.h"
#include "ast/sls/sls_bv_plugin.h"
#include "ast/sls/sls_basic_plugin.h"
#include "ast/sls/sls_datatype_plugin.h"
#include "ast/ast_ll_pp.h"
#include "ast/ast_pp.h"
#include "smt/params/smt_params_helper.hpp"
namespace sls {
plugin::plugin(context& c):
ctx(c),
m(c.get_manager()) {
}
context::context(ast_manager& m, sat_solver_context& s) :
m(m), s(s), m_atoms(m), m_allterms(m),
m_gd(*this),
m_ld(*this),
m_repair_down(m.get_num_asts(), m_gd),
m_repair_up(m.get_num_asts(), m_ld),
m_constraint_trail(m),
m_todo(m) {
}
void context::updt_params(params_ref const& p) {
smt_params_helper smtp(p);
m_rand.set_seed(smtp.random_seed());
m_params.append(p);
}
void context::register_plugin(plugin* p) {
m_plugins.reserve(p->fid() + 1);
m_plugins.set(p->fid(), p);
}
void context::ensure_plugin(family_id fid) {
if (m_plugins.get(fid, nullptr))
return;
else if (fid == arith_family_id)
register_plugin(alloc(arith_plugin, *this));
else if (fid == user_sort_family_id)
register_plugin(alloc(euf_plugin, *this));
else if (fid == basic_family_id)
register_plugin(alloc(basic_plugin, *this));
else if (fid == bv_util(m).get_family_id())
register_plugin(alloc(bv_plugin, *this));
else if (fid == array_util(m).get_family_id())
register_plugin(alloc(array_plugin, *this));
else if (fid == datatype_util(m).get_family_id())
register_plugin(alloc(datatype_plugin, *this));
else if (fid == null_family_id)
;
else
verbose_stream() << "did not find plugin for " << fid << "\n";
}
scoped_ptr<euf::egraph>& context::egraph() {
return euf().egraph();
}
euf_plugin& context::euf() {
auto fid = user_sort_family_id;
auto p = m_plugins.get(fid, nullptr);
if (!p) {
p = alloc(euf_plugin, *this);
register_plugin(p);
}
return *dynamic_cast<euf_plugin*>(p);
}
void context::ensure_plugin(expr* e) {
auto fid = get_fid(e);
ensure_plugin(fid);
fid = e->get_sort()->get_family_id();
ensure_plugin(fid);
}
void context::register_atom(sat::bool_var v, expr* e) {
m_atoms.setx(v, e);
m_atom2bool_var.setx(e->get_id(), v, sat::null_bool_var);
}
void context::on_restart() {
for (auto p : m_plugins)
if (p)
p->on_restart();
}
lbool context::check() {
//
// initialize data-structures if not done before.
// identify minimal feasible assignment to literals.
// sub-expressions within assignment are relevant.
// Use timestamps to make it incremental.
//
init();
while (unsat().empty() && m.inc()) {
propagate_boolean_assignment();
// verbose_stream() << "propagate " << unsat().size() << " " << m_new_constraint << "\n";
if (m_new_constraint || !unsat().empty())
return l_undef;
if (all_of(m_plugins, [&](auto* p) { return !p || p->is_sat(); })) {
values2model();
return l_true;
}
}
return l_undef;
}
void context::values2model() {
model_ref mdl = alloc(model, m);
expr_ref_vector args(m);
for (expr* e : subterms())
if (is_uninterp_const(e))
mdl->register_decl(to_app(e)->get_decl(), get_value(e));
for (expr* e : subterms()) {
if (!is_app(e))
continue;
auto f = to_app(e)->get_decl();
if (!include_func_interp(f))
continue;
auto v = get_value(e);
auto fi = mdl->get_func_interp(f);
if (!fi) {
fi = alloc(func_interp, m, f->get_arity());
mdl->register_decl(f, fi);
}
args.reset();
for (expr* arg : *to_app(e)) {
args.push_back(get_value(arg));
SASSERT(args.back());
}
SASSERT(f->get_arity() == args.size());
if (!fi->get_entry(args.data()))
fi->insert_new_entry(args.data(), v);
}
s.on_model(mdl);
// verbose_stream() << *mdl << "\n";
TRACE("sls", display(tout));
}
void context::propagate_boolean_assignment() {
reinit_relevant();
for (auto p : m_plugins)
if (p)
p->start_propagation();
for (sat::literal lit : root_literals())
propagate_literal(lit);
if (m_new_constraint)
return;
while (!m_new_constraint && m.inc() && (!m_repair_up.empty() || !m_repair_down.empty())) {
while (!m_repair_down.empty() && !m_new_constraint && m.inc()) {
auto id = m_repair_down.erase_min();
expr* e = term(id);
TRACE("sls", tout << "repair down " << mk_bounded_pp(e, m) << "\n");
if (is_app(e)) {
auto p = m_plugins.get(get_fid(e), nullptr);
++m_stats.m_num_repair_down;
if (p && !p->repair_down(to_app(e)) && !m_repair_up.contains(e->get_id())) {
IF_VERBOSE(3, verbose_stream() << "revert repair: " << mk_bounded_pp(e, m) << "\n");
m_repair_up.insert(e->get_id());
}
}
}
while (!m_repair_up.empty() && !m_new_constraint && m.inc()) {
auto id = m_repair_up.erase_min();
expr* e = term(id);
++m_stats.m_num_repair_up;
TRACE("sls", tout << "repair up " << mk_bounded_pp(e, m) << "\n");
if (is_app(e)) {
auto p = m_plugins.get(get_fid(e), nullptr);
if (p)
p->repair_up(to_app(e));
}
}
}
repair_literals();
// propagate "final checks"
bool propagated = true;
while (propagated && !m_new_constraint) {
propagated = false;
for (auto p : m_plugins)
propagated |= p && !m_new_constraint && p->propagate();
}
}
void context::repair_literals() {
for (sat::bool_var v = 0; v < s.num_vars() && !m_new_constraint; ++v) {
auto a = atom(v);
if (!a)
continue;
sat::literal lit(v, !is_true(v));
auto p = m_plugins.get(get_fid(a), nullptr);
if (p)
p->repair_literal(lit);
}
}
family_id context::get_fid(expr* e) const {
if (!is_app(e))
return user_sort_family_id;
family_id fid = to_app(e)->get_family_id();
if (m.is_eq(e))
fid = to_app(e)->get_arg(0)->get_sort()->get_family_id();
if (m.is_distinct(e))
fid = to_app(e)->get_arg(0)->get_sort()->get_family_id();
if ((fid == null_family_id && to_app(e)->get_num_args() > 0) || fid == model_value_family_id)
fid = user_sort_family_id;
return fid;
}
void context::propagate_literal(sat::literal lit) {
if (!is_true(lit))
return;
auto a = atom(lit.var());
if (!a)
return;
family_id fid = get_fid(a);
auto p = m_plugins.get(fid, nullptr);
if (p)
p->propagate_literal(lit);
if (!is_true(lit)) {
m_new_constraint = true;
}
}
bool context::is_true(expr* e) {
SASSERT(m.is_bool(e));
auto v = m_atom2bool_var.get(e->get_id(), sat::null_bool_var);
if (v != sat::null_bool_var)
return m.is_true(m_plugins[basic_family_id]->get_value(e));
else
return is_true(v);
}
bool context::is_fixed(expr* e) {
// is this a Boolean literal that is a unit?
return false;
}
expr_ref context::get_value(expr* e) {
sort* s = e->get_sort();
auto fid = s->get_family_id();
auto p = m_plugins.get(fid, nullptr);
if (p)
return p->get_value(e);
verbose_stream() << fid << " " << m.get_family_name(fid) << " " << mk_pp(e, m) << "\n";
UNREACHABLE();
return expr_ref(e, m);
}
bool context::set_value(expr * e, expr * v) {
return any_of(m_plugins, [&](auto p) { return p && p->set_value(e, v); });
}
bool context::is_relevant(expr* e) {
unsigned id = e->get_id();
if (m_relevant.contains(id))
return true;
if (m_visited.contains(id))
return false;
m_visited.insert(id);
if (m_parents.size() <= id)
verbose_stream() << "not in map " << mk_bounded_pp(e, m) << "\n";
for (auto p : m_parents[id]) {
if (is_relevant(p)) {
m_relevant.insert(id);
return true;
}
}
return false;
}
void context::add_constraint(expr* e) {
if (m_constraint_ids.contains(e->get_id()))
return;
m_constraint_ids.insert(e->get_id());
m_constraint_trail.push_back(e);
add_clause(e);
m_new_constraint = true;
++m_stats.m_num_constraints;
}
void context::add_clause(expr* f) {
expr_ref _e(f, m);
expr* g, * h, * k;
sat::literal_vector clause;
if (m.is_true(f))
return;
if (m.is_not(f, g) && m.is_not(g, g)) {
add_clause(g);
return;
}
bool sign = m.is_not(f, f);
if (!sign && m.is_or(f)) {
clause.reset();
for (auto arg : *to_app(f))
clause.push_back(mk_literal(arg));
s.add_clause(clause.size(), clause.data());
}
else if (!sign && m.is_and(f)) {
for (auto arg : *to_app(f))
add_clause(arg);
}
else if (sign && m.is_or(f)) {
for (auto arg : *to_app(f)) {
expr_ref fml(m.mk_not(arg), m);
add_clause(fml);
}
}
else if (!sign && m.is_implies(f, g, h)) {
clause.reset();
clause.push_back(~mk_literal(g));
clause.push_back(mk_literal(h));
s.add_clause(clause.size(), clause.data());
}
else if (sign && m.is_implies(f, g, h)) {
expr_ref fml(m.mk_not(h), m);
add_clause(fml);
add_clause(g);
}
else if (sign && m.is_and(f)) {
clause.reset();
for (auto arg : *to_app(f))
clause.push_back(~mk_literal(arg));
s.add_clause(clause.size(), clause.data());
}
else if (m.is_iff(f, g, h)) {
auto lit1 = mk_literal(g);
auto lit2 = mk_literal(h);
sat::literal cls1[2] = { sign ? lit1 : ~lit1, lit2 };
sat::literal cls2[2] = { sign ? ~lit1 : lit1, ~lit2 };
s.add_clause(2, cls1);
s.add_clause(2, cls2);
}
else if (m.is_ite(f, g, h, k)) {
auto lit1 = mk_literal(g);
auto lit2 = mk_literal(h);
auto lit3 = mk_literal(k);
// (g -> h) & (~g -> k)
// (g & h) | (~g & k)
// negated: (g -> ~h) & (g -> ~k)
sat::literal cls1[2] = { ~lit1, sign ? ~lit2 : lit2 };
sat::literal cls2[2] = { lit1, sign ? ~lit3 : lit3 };
s.add_clause(2, cls1);
s.add_clause(2, cls2);
}
else {
sat::literal lit = mk_literal(f);
if (sign)
lit.neg();
s.add_clause(1, &lit);
}
}
void context::add_clause(sat::literal_vector const& lits) {
s.add_clause(lits.size(), lits.data());
m_new_constraint = true;
++m_stats.m_num_constraints;
}
sat::literal context::mk_literal() {
sat::bool_var v = s.add_var();
return sat::literal(v, false);
}
sat::literal context::mk_literal(expr* e) {
expr_ref _e(e, m);
sat::literal lit;
bool neg = false;
expr* a, * b, * c;
while (m.is_not(e, e))
neg = !neg;
auto v = m_atom2bool_var.get(e->get_id(), sat::null_bool_var);
if (v != sat::null_bool_var)
return sat::literal(v, neg);
sat::literal_vector clause;
lit = mk_literal();
register_atom(lit.var(), e);
if (m.is_true(e)) {
clause.push_back(lit);
s.add_clause(clause.size(), clause.data());
}
else if (m.is_false(e)) {
clause.push_back(~lit);
s.add_clause(clause.size(), clause.data());
}
else if (m.is_and(e)) {
for (expr* arg : *to_app(e)) {
auto lit2 = mk_literal(arg);
clause.push_back(~lit2);
sat::literal lits[2] = { ~lit, lit2 };
s.add_clause(2, lits);
}
clause.push_back(lit);
s.add_clause(clause.size(), clause.data());
}
else if (m.is_or(e)) {
for (expr* arg : *to_app(e)) {
auto lit2 = mk_literal(arg);
clause.push_back(lit2);
sat::literal lits[2] = { lit, ~lit2 };
s.add_clause(2, lits);
}
clause.push_back(~lit);
s.add_clause(clause.size(), clause.data());
}
else if (m.is_iff(e, a, b) || m.is_xor(e, a, b)) {
auto lit1 = mk_literal(a);
auto lit2 = mk_literal(b);
if (m.is_xor(e))
lit2.neg();
sat::literal cls1[3] = { ~lit, ~lit1, lit2 };
sat::literal cls2[3] = { ~lit, lit1, ~lit2 };
sat::literal cls3[3] = { lit, lit1, lit2 };
sat::literal cls4[3] = { lit, ~lit1, ~lit2 };
s.add_clause(3, cls1);
s.add_clause(3, cls2);
s.add_clause(3, cls3);
s.add_clause(3, cls4);
}
else if (m.is_ite(e, a, b, c)) {
auto lit1 = mk_literal(a);
auto lit2 = mk_literal(b);
auto lit3 = mk_literal(c);
sat::literal cls1[3] = { ~lit, ~lit1, lit2 };
sat::literal cls2[3] = { ~lit, lit1, lit3 };
sat::literal cls3[3] = { lit, ~lit1, ~lit2 };
sat::literal cls4[3] = { lit, lit1, ~lit3 };
s.add_clause(3, cls1);
s.add_clause(3, cls2);
s.add_clause(3, cls3);
s.add_clause(3, cls4);
}
else
register_terms(e);
return neg ? ~lit : lit;
}
void context::init() {
m_new_constraint = false;
if (m_initialized)
return;
m_initialized = true;
m_unit_literals.reset();
m_unit_indices.reset();
for (auto const& clause : s.clauses())
if (clause.m_clause.size() == 1)
m_unit_literals.push_back(clause.m_clause[0]);
for (sat::literal lit : m_unit_literals)
m_unit_indices.insert(lit.index());
IF_VERBOSE(3, verbose_stream() << "UNITS " << m_unit_literals << "\n");
for (unsigned i = 0; i < m_atoms.size(); ++i)
if (m_atoms.get(i))
register_terms(m_atoms.get(i));
for (auto p : m_plugins)
if (p)
p->initialize();
}
void context::register_terms(expr* e) {
auto is_visited = [&](expr* e) {
return nullptr != m_allterms.get(e->get_id(), nullptr);
};
auto visit = [&](expr* e) {
m_allterms.setx(e->get_id(), e);
ensure_plugin(e);
register_term(e);
};
if (is_visited(e))
return;
m_subterms.reset();
m_todo.push_back(e);
if (m_todo.size() > 1)
return;
while (!m_todo.empty()) {
expr* e = m_todo.back();
if (is_visited(e))
m_todo.pop_back();
else if (is_app(e)) {
if (all_of(*to_app(e), [&](expr* arg) { return is_visited(arg); })) {
expr_ref _e(e, m);
m_todo.pop_back();
m_parents.reserve(to_app(e)->get_id() + 1);
for (expr* arg : *to_app(e)) {
m_parents.reserve(arg->get_id() + 1);
m_parents[arg->get_id()].push_back(e);
}
if (m.is_bool(e))
mk_literal(e);
visit(e);
}
else {
for (expr* arg : *to_app(e))
m_todo.push_back(arg);
}
}
else {
expr_ref _e(e, m);
m_todo.pop_back();
visit(e);
}
}
}
void context::new_value_eh(expr* e) {
DEBUG_CODE(
if (m.is_bool(e)) {
auto v = m_atom2bool_var.get(e->get_id(), sat::null_bool_var);
if (v != sat::null_bool_var) {
SASSERT(m.is_true(get_value(e)) == is_true(v));
}
}
);
m_repair_down.reserve(e->get_id() + 1);
m_repair_up.reserve(e->get_id() + 1);
if (!term(e->get_id()))
verbose_stream() << "no term " << mk_bounded_pp(e, m) << "\n";
SASSERT(e == term(e->get_id()));
if (!m_repair_down.contains(e->get_id()))
m_repair_down.insert(e->get_id());
for (auto p : parents(e)) {
auto pid = p->get_id();
m_repair_up.reserve(pid + 1);
m_repair_down.reserve(pid + 1);
if (!m_repair_up.contains(pid))
m_repair_up.insert(pid);
}
}
void context::register_term(expr* e) {
for (auto p : m_plugins)
if (p)
p->register_term(e);
}
ptr_vector<expr> const& context::subterms() {
if (!m_subterms.empty())
return m_subterms;
for (auto e : m_allterms)
if (e)
m_subterms.push_back(e);
std::stable_sort(m_subterms.begin(), m_subterms.end(),
[](expr* a, expr* b) { return get_depth(a) < get_depth(b); });
return m_subterms;
}
void context::reinit_relevant() {
m_relevant.reset();
m_visited.reset();
m_root_literals.reset();
for (auto const& clause : s.clauses()) {
bool has_relevant = false;
unsigned n = 0;
sat::literal selected_lit = sat::null_literal;
for (auto lit : clause) {
auto atm = m_atoms.get(lit.var(), nullptr);
if (!atm)
continue;
auto a = atm->get_id();
if (!is_true(lit))
continue;
if (m_relevant.contains(a)) {
has_relevant = true;
break;
}
if (m_rand() % ++n == 0)
selected_lit = lit;
}
if (!has_relevant && selected_lit != sat::null_literal) {
m_relevant.insert(m_atoms[selected_lit.var()]->get_id());
m_root_literals.push_back(selected_lit);
}
}
shuffle(m_root_literals.size(), m_root_literals.data(), m_rand);
}
std::ostream& context::display(std::ostream& out) const {
for (auto id : m_repair_down)
out << "d " << mk_bounded_pp(term(id), m) << "\n";
for (auto id : m_repair_up)
out << "u " << mk_bounded_pp(term(id), m) << "\n";
for (unsigned v = 0; v < m_atoms.size(); ++v) {
auto e = m_atoms[v];
if (e)
out << v << ": " << mk_bounded_pp(e, m) << " := " << (is_true(v)?"T":"F") << "\n";
}
for (auto p : m_plugins)
if (p)
p->display(out);
return out;
}
void context::collect_statistics(statistics& st) const {
for (auto p : m_plugins)
if (p)
p->collect_statistics(st);
st.update("sls-repair-down", m_stats.m_num_repair_down);
st.update("sls-repair-up", m_stats.m_num_repair_up);
st.update("sls-constraints", m_stats.m_num_constraints);
}
void context::reset_statistics() {
for (auto p : m_plugins)
if (p)
p->reset_statistics();
m_stats.reset();
}
}

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/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
sls_context.h
Abstract:
A Stochastic Local Search (SLS) Context.
Author:
Nikolaj Bjorner (nbjorner) 2024-06-24
--*/
#pragma once
#include "util/sat_literal.h"
#include "util/sat_sls.h"
#include "util/statistics.h"
#include "ast/ast.h"
#include "ast/euf/euf_egraph.h"
#include "model/model.h"
#include "util/scoped_ptr_vector.h"
#include "util/obj_hashtable.h"
#include "util/heap.h"
namespace sls {
class context;
class euf_plugin;
class plugin {
protected:
context& ctx;
ast_manager& m;
family_id m_fid;
public:
plugin(context& c);
virtual ~plugin() {}
virtual family_id fid() { return m_fid; }
virtual void register_term(expr* e) = 0;
virtual expr_ref get_value(expr* e) = 0;
virtual void initialize() = 0;
virtual void start_propagation() {};
virtual bool propagate() = 0;
virtual void propagate_literal(sat::literal lit) = 0;
virtual void repair_literal(sat::literal lit) = 0;
virtual bool repair_down(app* e) = 0;
virtual void repair_up(app* e) = 0;
virtual bool is_sat() = 0;
virtual void on_rescale() {};
virtual void on_restart() {};
virtual std::ostream& display(std::ostream& out) const = 0;
virtual bool set_value(expr* e, expr* v) = 0;
virtual void collect_statistics(statistics& st) const = 0;
virtual void reset_statistics() = 0;
virtual bool include_func_interp(func_decl* f) const { return false; }
};
using clause = ptr_iterator<sat::literal>;
class sat_solver_context {
public:
virtual ~sat_solver_context() {}
virtual vector<sat::clause_info> const& clauses() const = 0;
virtual sat::clause_info const& get_clause(unsigned idx) const = 0;
virtual ptr_iterator<unsigned> get_use_list(sat::literal lit) = 0;
virtual void flip(sat::bool_var v) = 0;
virtual double reward(sat::bool_var v) = 0;
virtual double get_weigth(unsigned clause_idx) = 0;
virtual bool is_true(sat::literal lit) = 0;
virtual unsigned num_vars() const = 0;
virtual indexed_uint_set const& unsat() const = 0;
virtual void on_model(model_ref& mdl) = 0;
virtual sat::bool_var add_var() = 0;
virtual void add_clause(unsigned n, sat::literal const* lits) = 0;
virtual void force_restart() = 0;
virtual std::ostream& display(std::ostream& out) = 0;
};
class context {
struct greater_depth {
context& c;
greater_depth(context& c) : c(c) {}
bool operator()(unsigned x, unsigned y) const {
return get_depth(c.term(x)) > get_depth(c.term(y));
}
};
struct less_depth {
context& c;
less_depth(context& c) : c(c) {}
bool operator()(unsigned x, unsigned y) const {
return get_depth(c.term(x)) < get_depth(c.term(y));
}
};
struct stats {
unsigned m_num_repair_down = 0;
unsigned m_num_repair_up = 0;
unsigned m_num_constraints = 0;
void reset() { memset(this, 0, sizeof(*this)); }
};
ast_manager& m;
sat_solver_context& s;
scoped_ptr_vector<plugin> m_plugins;
indexed_uint_set m_relevant, m_visited;
expr_ref_vector m_atoms;
unsigned_vector m_atom2bool_var;
params_ref m_params;
vector<ptr_vector<expr>> m_parents;
sat::literal_vector m_root_literals, m_unit_literals;
indexed_uint_set m_unit_indices;
random_gen m_rand;
bool m_initialized = false;
bool m_new_constraint = false;
bool m_dirty = false;
expr_ref_vector m_allterms;
ptr_vector<expr> m_subterms;
greater_depth m_gd;
less_depth m_ld;
heap<greater_depth> m_repair_down;
heap<less_depth> m_repair_up;
uint_set m_constraint_ids;
expr_ref_vector m_constraint_trail;
stats m_stats;
void register_plugin(plugin* p);
void init();
expr_ref_vector m_todo;
void register_terms(expr* e);
void register_term(expr* e);
void propagate_boolean_assignment();
void propagate_literal(sat::literal lit);
void repair_literals();
void values2model();
void ensure_plugin(expr* e);
void ensure_plugin(family_id fid);
family_id get_fid(expr* e) const;
sat::literal mk_literal();
public:
context(ast_manager& m, sat_solver_context& s);
// Between SAT/SMT solver and context.
void register_atom(sat::bool_var v, expr* e);
lbool check();
void on_restart();
void updt_params(params_ref const& p);
params_ref const& get_params() const { return m_params; }
// expose sat_solver to plugins
vector<sat::clause_info> const& clauses() const { return s.clauses(); }
sat::clause_info const& get_clause(unsigned idx) const { return s.get_clause(idx); }
ptr_iterator<unsigned> get_use_list(sat::literal lit) { return s.get_use_list(lit); }
double get_weight(unsigned clause_idx) { return s.get_weigth(clause_idx); }
unsigned num_bool_vars() const { return s.num_vars(); }
bool is_true(sat::literal lit) { return s.is_true(lit); }
bool is_true(sat::bool_var v) const { return s.is_true(sat::literal(v, false)); }
expr* atom(sat::bool_var v) { return m_atoms.get(v, nullptr); }
expr* term(unsigned id) const { return m_allterms.get(id); }
sat::bool_var atom2bool_var(expr* e) const { return m_atom2bool_var.get(e->get_id(), sat::null_bool_var); }
sat::literal mk_literal(expr* e);
void add_clause(expr* f);
void add_clause(sat::literal_vector const& lits);
void flip(sat::bool_var v) { s.flip(v); }
double reward(sat::bool_var v) { return s.reward(v); }
indexed_uint_set const& unsat() const { return s.unsat(); }
unsigned rand() { return m_rand(); }
unsigned rand(unsigned n) { return m_rand(n); }
sat::literal_vector const& root_literals() const { return m_root_literals; }
sat::literal_vector const& unit_literals() const { return m_unit_literals; }
bool is_unit(sat::literal lit) const { return m_unit_indices.contains(lit.index()); }
void reinit_relevant();
void force_restart() { s.force_restart(); }
bool include_func_interp(func_decl* f) const { return any_of(m_plugins, [&](plugin* p) { return p && p->include_func_interp(f); }); }
ptr_vector<expr> const& parents(expr* e) {
m_parents.reserve(e->get_id() + 1);
return m_parents[e->get_id()];
}
// Between plugin solvers
expr_ref get_value(expr* e);
bool set_value(expr* e, expr* v);
void new_value_eh(expr* e);
bool is_true(expr* e);
bool is_fixed(expr* e);
bool is_relevant(expr* e);
void add_constraint(expr* e);
ptr_vector<expr> const& subterms();
ast_manager& get_manager() { return m; }
std::ostream& display(std::ostream& out) const;
std::ostream& display_all(std::ostream& out) const { return s.display(out); }
scoped_ptr<euf::egraph>& egraph();
euf_plugin& euf();
void collect_statistics(statistics& st) const;
void reset_statistics();
};
}

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/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
sls_datatype_plugin.cpp
Abstract:
Algebraic Datatypes for SLS
Author:
Nikolaj Bjorner (nbjorner) 2024-10-14
Notes:
Eager reduction to EUF:
is-c(c(t)) for each c(t) in T
acc_i(c(t_i)) = t_i for each c(..t_i..) in T
is-c(t) => t = c(...acc_j(t)..) for each acc_j(t) in T
sum_i is-c_i(t) = 1
is-c(t) <=> c = t for each 0-ary constructor c
is-c(t) <=> t = c(acc_1(t)..acc_n(t))
s = acc(...(acc(t)) => s != t if t is recursive
or_i t = t_i if t is a finite sort with terms t_i
s := acc(t) => s < t in P
a := s = acc(t), a is a unit => s < t in P
a := s = acc(t), a in Atoms => (a => s < t) in P
s << t if there is a path P with conditions L.
L => s != t
This disregards if acc is applied to non-matching constructor.
In this case we rely on that the interpretation of acc can be
forced.
If this is incorrect, include is-c(t) assumptions in path axioms.
Is P sufficient? Should we just consider all possible paths of depth at most k to be safe?
Example:
C(acc(t)) == C(s)
triggers equation acc(t) = s, but the equation is implicit, so acc(t) and s are not directly
connected.
Even, the axioms extracted from P don't consider transitivity of =.
So the can-be-equal alias approximation is too strong.
We therefore add an occurs check during propagation and lazily add missed axioms.
Model-repair based:
1. Initialize uninterpreted datatype nodes to hold arbitrary values.
2. Initialize datatype nodes by induced evaluation.
3. Atomic constraints are of the form for datatype terms
x = y, x = t, x != y, x != t; s = t, s != t
violated x = y: x <- eval(y), y <- eval(x) or x, y <- fresh
violated x = t: x <- eval(t), repair t using the shape of x
violated x != y: x <- fresh, y <- fresh
violated x != t: x <- fresh, subterm y of t: y <- fresh
acc(x) = t: eval(x) = c(u, v) acc(c(u,v)) = u -> repair(u = t)
acc(x) = t: eval(x) does not match acc -> acc(x)
has a fixed interpretation, so repair over t instead, or update interpretation of x
uses:
model::get_fresh_value(s)
model::get_some_value(s)
--*/
#include "ast/sls/sls_datatype_plugin.h"
#include "ast/sls/sls_euf_plugin.h"
#include "ast/ast_pp.h"
#include "params/sls_params.hpp"
namespace sls {
datatype_plugin::datatype_plugin(context& c):
plugin(c),
euf(c.euf()),
g(c.egraph()),
dt(m),
m_axioms(m),
m_values(m),
m_eval(m) {
m_fid = dt.get_family_id();
}
datatype_plugin::~datatype_plugin() {}
void datatype_plugin::collect_path_axioms() {
expr* t = nullptr, *z = nullptr;
for (auto s : ctx.subterms()) {
if (dt.is_accessor(s, t) && dt.is_recursive(t) && dt.is_recursive(s))
add_edge(s, t, m.mk_app(dt.get_constructor_is(dt.get_accessor_constructor(to_app(s)->get_decl())), t));
if (dt.is_constructor(s) && dt.is_recursive(s)) {
for (auto arg : *to_app(s))
add_edge(arg, s, nullptr);
}
}
expr* x = nullptr, *y = nullptr;
for (sat::bool_var v = 0; v < ctx.num_bool_vars(); ++v) {
expr* e = ctx.atom(v);
if (!e)
continue;
if (!m.is_eq(e, x, y))
continue;
if (!dt.is_recursive(x))
continue;
sat::literal lp(v, false), ln(v, true);
if (dt.is_accessor(x, z) && dt.is_recursive(z)) {
if (ctx.is_unit(lp))
add_edge(y, z, nullptr);
else if (ctx.is_unit(ln))
;
else
add_edge(y, z, e);
}
if (dt.is_accessor(y, z) && dt.is_recursive(z)) {
if (ctx.is_unit(lp))
add_edge(x, z, m.mk_app(dt.get_constructor_is(dt.get_accessor_constructor(to_app(y)->get_decl())), z));
else if (ctx.is_unit(ln))
;
else
add_edge(x, z, e);
}
}
add_path_axioms();
}
void datatype_plugin::add_edge(expr* child, expr* parent, expr* cond) {
m_parents.insert_if_not_there(child, vector<parent_t>()).push_back({parent, expr_ref(cond, m)});
TRACE("dt", tout << mk_bounded_pp(child, m) << " <- " << mk_bounded_pp(parent, m) << " " << mk_bounded_pp(cond, m) << "\n");
}
void datatype_plugin::add_path_axioms() {
ptr_vector<expr> path;
sat::literal_vector lits;
for (auto [child, parents] : m_parents) {
path.reset();
lits.reset();
path.push_back(child);
add_path_axioms(path, lits, parents);
}
}
void datatype_plugin::add_path_axioms(ptr_vector<expr>& children, sat::literal_vector& lits, vector<parent_t> const& parents) {
for (auto const& [parent, cond] : parents) {
if (cond)
lits.push_back(~ctx.mk_literal(cond));
if (children.contains(parent)) {
// only assert loop clauses for proper loops
if (parent == children[0])
ctx.add_clause(lits);
if (cond)
lits.pop_back();
continue;
}
if (children[0]->get_sort() == parent->get_sort()) {
lits.push_back(~ctx.mk_literal(m.mk_eq(children[0], parent)));
TRACE("dt", for (auto lit : lits) tout << (lit.sign() ? "~": "") << mk_pp(ctx.atom(lit.var()), m) << "\n";);
ctx.add_clause(lits);
lits.pop_back();
}
auto child = children.back();
if (m_parents.contains(child)) {
children.push_back(parent);
auto& parents2 = m_parents[child];
add_path_axioms(children, lits, parents2);
children.pop_back();
}
if (cond)
lits.pop_back();
}
}
void datatype_plugin::add_axioms() {
expr_ref_vector axioms(m);
for (auto t : ctx.subterms()) {
auto s = t->get_sort();
if (dt.is_datatype(s))
m_dts.insert_if_not_there(s, ptr_vector<expr>()).push_back(t);
if (!is_app(t))
continue;
auto ta = to_app(t);
auto f = ta->get_decl();
if (dt.is_constructor(t)) {
auto r = dt.get_constructor_is(f);
m_axioms.push_back(m.mk_app(r, t));
auto& acc = *dt.get_constructor_accessors(f);
for (unsigned i = 0; i < ta->get_num_args(); ++i) {
auto ti = ta->get_arg(i);
m_axioms.push_back(m.mk_eq(ti, m.mk_app(acc[i], t)));
}
auto& cns = *dt.get_datatype_constructors(s);
for (auto c : cns) {
if (c != f) {
auto r2 = dt.get_constructor_is(c);
m_axioms.push_back(m.mk_not(m.mk_app(r2, t)));
}
}
continue;
}
if (dt.is_recognizer0(f)) {
auto u = ta->get_arg(0);
auto c = dt.get_recognizer_constructor(f);
m_axioms.push_back(m.mk_iff(t, m.mk_app(dt.get_constructor_is(c), u)));
}
if (dt.is_update_field(t)) {
NOT_IMPLEMENTED_YET();
}
if (dt.is_datatype(s)) {
auto& cns = *dt.get_datatype_constructors(s);
expr_ref_vector ors(m);
for (auto c : cns) {
auto r = dt.get_constructor_is(c);
ors.push_back(m.mk_app(r, t));
}
m_axioms.push_back(m.mk_or(ors));
#if 0
// expanded lazily
// EUF already handles enumeration datatype case.
for (unsigned i = 0; i < cns.size(); ++i) {
auto r1 = dt.get_constructor_is(cns[i]);
for (unsigned j = i + 1; j < cns.size(); ++j) {
auto r2 = dt.get_constructor_is(cns[j]);
m_axioms.push_back(m.mk_or(m.mk_not(m.mk_app(r1, t)), m.mk_not(m.mk_app(r2, t))));
}
}
#endif
for (auto c : cns) {
auto r = dt.get_constructor_is(c);
auto& acc = *dt.get_constructor_accessors(c);
expr_ref_vector args(m);
for (auto a : acc)
args.push_back(m.mk_app(a, t));
m_axioms.push_back(m.mk_iff(m.mk_app(r, t), m.mk_eq(t, m.mk_app(c, args))));
}
}
}
//collect_path_axioms();
TRACE("dt", for (auto a : m_axioms) tout << mk_pp(a, m) << "\n";);
for (auto a : m_axioms)
ctx.add_constraint(a);
}
void datatype_plugin::initialize() {
sls_params sp(ctx.get_params());
m_axiomatic_mode = sp.dt_axiomatic();
if (m_axiomatic_mode)
add_axioms();
}
expr_ref datatype_plugin::get_value(expr* e) {
if (!dt.is_datatype(e))
return expr_ref(m);
if (m_axiomatic_mode) {
init_values();
return expr_ref(m_values.get(g->find(e)->get_root_id()), m);
}
return expr_ref(m_eval.get(e->get_id()), m);
}
void datatype_plugin::init_values() {
if (!m_values.empty())
return;
TRACE("dt", g->display(tout));
m_model = alloc(model, m);
// retrieve e-graph from sls_euf_solver: add bridge in sls_context to share e-graph
SASSERT(g);
// build top_sort<euf::enode> similar to dt_solver.cpp
top_sort<euf::enode> deps;
for (auto* n : g->nodes())
if (n->is_root())
add_dep(n, deps);
auto trace_assignment = [&](std::ostream& out, euf::enode* n) {
for (auto sib : euf::enode_class(n))
out << g->bpp(sib) << " ";
out << " <- " << mk_bounded_pp(m_values.get(n->get_id()), m) << "\n";
};
deps.topological_sort();
expr_ref_vector args(m);
euf::enode_vector leaves, worklist;
obj_map<euf::enode, euf::enode_vector> leaf2root;
// walk topological sort in order of leaves to roots, attaching values to nodes.
for (euf::enode* n : deps.top_sorted()) {
SASSERT(n->is_root());
unsigned id = n->get_id();
if (m_values.get(id, nullptr))
continue;
expr* e = n->get_expr();
m_values.reserve(id + 1);
if (!dt.is_datatype(e))
continue;
euf::enode* con = get_constructor(n);
if (!con) {
leaves.push_back(n);
continue;
}
auto f = con->get_decl();
args.reset();
bool has_null = false;
for (auto arg : euf::enode_args(con)) {
if (dt.is_datatype(arg->get_sort())) {
auto val_arg = m_values.get(arg->get_root_id());
if (!val_arg)
has_null = true;
leaf2root.insert_if_not_there(arg->get_root(), euf::enode_vector()).push_back(n);
args.push_back(val_arg);
}
else
args.push_back(ctx.get_value(arg->get_expr()));
}
if (!has_null) {
m_values.setx(id, m.mk_app(f, args));
m_model->register_value(m_values.get(id));
TRACE("dt", tout << "Set interpretation "; trace_assignment(tout, n););
}
}
TRACE("dt",
for (euf::enode* n : deps.top_sorted()) {
tout << g->bpp(n) << ": ";
tout << g->bpp(get_constructor(n)) << " :: ";
auto s = deps.get_dep(n);
if (s) {
tout << " -> ";
for (auto t : *s)
tout << g->bpp(t) << " ";
}
tout << "\n";
}
);
auto process_workitem = [&](euf::enode* n) {
if (!leaf2root.contains(n))
return true;
bool all_processed = true;
for (auto p : leaf2root[n]) {
if (m_values.get(p->get_id(), nullptr))
continue;
auto con = get_constructor(p);
SASSERT(con);
auto f = con->get_decl();
args.reset();
bool has_missing = false;
for (auto arg : euf::enode_args(con)) {
if (dt.is_datatype(arg->get_sort())) {
auto arg_val = m_values.get(arg->get_root_id());
if (!arg_val)
has_missing = true;
args.push_back(arg_val);
}
else
args.push_back(ctx.get_value(arg->get_expr()));
}
if (has_missing) {
all_processed = false;
continue;
}
worklist.push_back(p);
SASSERT(all_of(args, [&](expr* e) { return e != nullptr; }));
m_values.setx(p->get_id(), m.mk_app(f, args));
TRACE("dt", tout << "Patched interpretation "; trace_assignment(tout, p););
m_model->register_value(m_values.get(p->get_id()));
}
return all_processed;
};
auto process_worklist = [&](euf::enode_vector& worklist) {
unsigned j = 0, sz = worklist.size();
for (unsigned i = 0; i < worklist.size(); ++i)
if (!process_workitem(worklist[i]))
worklist[j++] = worklist[i];
worklist.shrink(j);
return j < sz;
};
// attach fresh values to each leaf, walk up parents to assign them values.
while (!leaves.empty()) {
auto n = leaves.back();
leaves.pop_back();
SASSERT(!get_constructor(n));
auto v = m_model->get_fresh_value(n->get_sort());
if (!v)
v = m_model->get_some_value(n->get_sort());
SASSERT(v);
unsigned id = n->get_id();
m_values.setx(id, v);
TRACE("dt", tout << "Fresh interpretation "; trace_assignment(tout, n););
worklist.reset();
worklist.push_back(n);
while (process_worklist(worklist))
;
}
}
void datatype_plugin::add_dep(euf::enode* n, top_sort<euf::enode>& dep) {
if (!dt.is_datatype(n->get_expr()))
return;
euf::enode* con = get_constructor(n);
TRACE("dt", tout << g->bpp(n) << " con: " << g->bpp(con) << "\n";);
if (!con)
dep.insert(n, nullptr);
else if (con->num_args() == 0)
dep.insert(n, nullptr);
else
for (euf::enode* arg : euf::enode_args(con))
dep.add(n, arg->get_root());
}
void datatype_plugin::start_propagation() {
m_values.reset();
m_model = nullptr;
}
euf::enode* datatype_plugin::get_constructor(euf::enode* n) const {
for (auto sib : euf::enode_class(n))
if (dt.is_constructor(sib->get_expr()))
return sib;
return nullptr;
}
bool datatype_plugin::propagate() {
enum color_t { white, grey, black };
svector<color_t> color;
ptr_vector<euf::enode> stack;
obj_map<sort, ptr_vector<expr>> sorts;
auto set_conflict = [&](euf::enode* n) {
expr_ref_vector diseqs(m);
while (true) {
auto n2 = stack.back();
auto con2 = get_constructor(n2);
if (n2 != con2)
diseqs.push_back(m.mk_not(m.mk_eq(n2->get_expr(), con2->get_expr())));
if (n2->get_root() == n->get_root()) {
if (n != n2)
diseqs.push_back(m.mk_not(m.mk_eq(n->get_expr(), n2->get_expr())));
break;
}
stack.pop_back();
}
IF_VERBOSE(1, verbose_stream() << "cycle\n"; for (auto e : diseqs) verbose_stream() << mk_pp(e, m) << "\n";);
ctx.add_constraint(m.mk_or(diseqs));
++m_stats.m_num_occurs;
};
for (auto n : g->nodes()) {
if (!n->is_root())
continue;
euf::enode* con = nullptr;
for (auto sib : euf::enode_class(n)) {
if (dt.is_constructor(sib->get_expr())) {
if (!con)
con = sib;
if (con && con->get_decl() != sib->get_decl()) {
ctx.add_constraint(m.mk_not(m.mk_eq(con->get_expr(), sib->get_expr())));
++m_stats.m_num_occurs;
}
}
}
}
for (auto n : g->nodes()) {
if (!n->is_root())
continue;
expr* e = n->get_expr();
if (!dt.is_datatype(e))
continue;
if (!ctx.is_relevant(e))
continue;
sort* s = e->get_sort();
sorts.insert_if_not_there(s, ptr_vector<expr>()).push_back(e);
auto c = color.get(e->get_id(), white);
SASSERT(c != grey);
if (c == black)
continue;
// dfs traversal of enodes, starting with n,
// with outgoing edges the arguments of con, where con
// is a node in the same congruence class as n that is a constructor.
// For every cycle accumulate a conflict.
stack.push_back(n);
while (!stack.empty()) {
n = stack.back();
unsigned id = n->get_root_id();
c = color.get(id, white);
euf::enode* con;
switch (c) {
case black:
stack.pop_back();
break;
case grey:
case white:
color.setx(id, grey, white);
con = get_constructor(n);
if (!con)
goto done_with_node;
for (auto child : euf::enode_args(con)) {
auto c2 = color.get(child->get_root_id(), white);
switch (c2) {
case black:
break;
case grey:
set_conflict(child);
return true;
case white:
stack.push_back(child);
goto node_pushed;
}
}
done_with_node:
color[id] = black;
stack.pop_back();
node_pushed:
break;
}
}
}
for (auto const& [s, elems] : sorts) {
auto sz = s->get_num_elements();
if (!sz.is_finite() || sz.size() >= elems.size())
continue;
ctx.add_constraint(m.mk_not(m.mk_distinct((unsigned)sz.size() + 1, elems.data())));
}
return false;
}
bool datatype_plugin::include_func_interp(func_decl* f) const {
if (!dt.is_accessor(f))
return false;
func_decl* con_decl = dt.get_accessor_constructor(f);
for (euf::enode* app : g->enodes_of(f)) {
euf::enode* con = get_constructor(app->get_arg(0));
if (con && con->get_decl() != con_decl)
return true;
}
return false;
}
std::ostream& datatype_plugin::display(std::ostream& out) const {
for (auto a : m_axioms)
out << mk_bounded_pp(a, m, 3) << "\n";
return out;
}
void datatype_plugin::propagate_literal(sat::literal lit) {
if (m_axiomatic_mode)
euf.propagate_literal(lit);
else
propagate_literal_model_building(lit);
}
void datatype_plugin::propagate_literal_model_building(sat::literal lit) {
if (!ctx.is_true(lit))
return;
auto a = ctx.atom(lit.var());
if (!a || !is_app(a))
return;
repair_down(to_app(a));
}
bool datatype_plugin::is_sat() { return true; }
void datatype_plugin::register_term(expr* e) {
expr* t = nullptr;
if (dt.is_accessor(e, t)) {
auto f = to_app(e)->get_decl();
m_occurs.insert_if_not_there(f, expr_set()).insert(e);
m_eval_accessor.insert_if_not_there(f, obj_map<expr, expr*>());
}
}
bool datatype_plugin::repair_down(app* e) {
expr* t, * s;
auto v0 = eval0(e);
auto v1 = eval1(e);
if (v0 == v1)
return true;
IF_VERBOSE(2, verbose_stream() << "dt-repair-down " << mk_bounded_pp(e, m) << " " << v0 << " <- " << v1 << "\n");
if (dt.is_constructor(e))
repair_down_constructor(e, v0, v1);
else if (dt.is_accessor(e, t))
repair_down_accessor(e, t, v0);
else if (dt.is_recognizer(e, t))
repair_down_recognizer(e, t);
else if (m.is_eq(e, s, t))
repair_down_eq(e, s, t);
else if (m.is_distinct(e))
repair_down_distinct(e);
else {
UNREACHABLE();
}
return false;
}
//
// C(t) <- C(s) then repair t <- s
// C(t) <- D(s) then fail the repair.
//
void datatype_plugin::repair_down_constructor(app* e, expr* v0, expr* v1) {
SASSERT(dt.is_constructor(v0));
SASSERT(dt.is_constructor(v1));
SASSERT(e->get_decl() == to_app(v1)->get_decl());
if (e->get_decl() == to_app(v0)->get_decl()) {
for (unsigned i = 0; i < e->get_num_args(); ++i) {
auto w0 = to_app(v0)->get_arg(i);
auto w1 = to_app(v1)->get_arg(i);
if (w0 == w1)
continue;
expr* arg = e->get_arg(i);
set_eval0(arg, w0);
ctx.new_value_eh(arg);
}
}
}
//
// A_D(t) <- s, val(t) = D(..s'..) then update val(t) to agree with s
// A_D(t) <- s, val(t) = C(..) then set t to D(...s...)
// , eval(val(A_D(t))) = s' then update eval(val(A_D,(t))) to s'
void datatype_plugin::repair_down_accessor(app* e, expr* t, expr* v0) {
auto f = e->get_decl();
auto c = dt.get_accessor_constructor(f);
auto val_t = eval0(t);
SASSERT(dt.is_constructor(val_t));
expr_ref_vector args(m);
auto const& accs = *dt.get_constructor_accessors(c);
unsigned i;
for (i = 0; i < accs.size(); ++i) {
if (accs[i] == f)
break;
}
SASSERT(i < accs.size());
if (to_app(val_t)->get_decl() == c) {
if (to_app(val_t)->get_arg(i) == v0)
return;
args.append(accs.size(), to_app(val_t)->get_args());
args[i] = v0;
expr* new_val_t = m.mk_app(c, args);
set_eval0(t, new_val_t);
ctx.new_value_eh(t);
return;
}
if (ctx.rand(5) != 0) {
update_eval_accessor(e, val_t, v0);
return;
}
for (unsigned j = 0; j < accs.size(); ++j) {
if (i == j)
args[i] = v0;
else
args[j] = m_model->get_some_value(accs[j]->get_range());
}
expr* new_val_t = m.mk_app(c, args);
set_eval0(t, new_val_t);
ctx.new_value_eh(t);
}
void datatype_plugin::repair_down_recognizer(app* e, expr* t) {
auto bv = ctx.atom2bool_var(e);
auto is_true = ctx.is_true(bv);
auto c = dt.get_recognizer_constructor(e->get_decl());
auto val_t = eval0(t);
auto const& cons = *dt.get_datatype_constructors(t->get_sort());
auto set_to_instance = [&](func_decl* c) {
auto const& accs = *dt.get_constructor_accessors(c);
expr_ref_vector args(m);
for (auto a : accs)
args.push_back(m_model->get_some_value(a->get_range()));
set_eval0(t, m.mk_app(c, args));
ctx.new_value_eh(t);
};
auto different_constructor = [&](func_decl* c) {
unsigned i = 0;
func_decl* c_new = nullptr;
for (auto c2 : cons)
if (c2 != c && ctx.rand(++i) == 0)
c_new = c2;
return c_new;
};
SASSERT(dt.is_constructor(val_t));
if (c == to_app(val_t)->get_decl() && is_true)
return;
if (c != to_app(val_t)->get_decl() && !is_true)
return;
if (ctx.rand(10) == 0)
ctx.flip(bv);
else if (is_true)
set_to_instance(c);
else if (cons.size() == 1)
ctx.flip(bv);
else
set_to_instance(different_constructor(c));
}
void datatype_plugin::repair_down_eq(app* e, expr* s, expr* t) {
auto bv = ctx.atom2bool_var(e);
auto is_true = ctx.is_true(bv);
auto vs = eval0(s);
auto vt = eval0(t);
if (is_true && vs == vt)
return;
if (!is_true && vs != vt)
return;
if (is_true) {
auto coin = ctx.rand(5);
if (coin <= 1) {
set_eval0(s, vt);
ctx.new_value_eh(s);
return;
}
if (coin <= 3) {
set_eval0(t, vs);
ctx.new_value_eh(t);
}
if (true) {
auto new_v = m_model->get_some_value(s->get_sort());
set_eval0(s, new_v);
set_eval0(t, new_v);
ctx.new_value_eh(s);
ctx.new_value_eh(t);
return;
}
}
auto coin = ctx.rand(10);
if (coin <= 4) {
auto new_v = m_model->get_some_value(s->get_sort());
set_eval0(s, new_v);
ctx.new_value_eh(s);
return;
}
if (coin <= 9) {
auto new_v = m_model->get_some_value(s->get_sort());
set_eval0(t, new_v);
ctx.new_value_eh(t);
return;
}
}
void datatype_plugin::repair_down_distinct(app* e) {
auto bv = ctx.atom2bool_var(e);
auto is_true = ctx.is_true(bv);
unsigned sz = e->get_num_args();
for (unsigned i = 0; i < sz; ++i) {
auto val1 = eval0(e->get_arg(i));
for (unsigned j = i + 1; j < sz; ++j) {
auto val2 = eval0(e->get_arg(j));
if (val1 != val2)
continue;
if (!is_true)
return;
if (ctx.rand(2) == 0)
std::swap(i, j);
auto new_v = m_model->get_some_value(e->get_arg(i)->get_sort());
set_eval0(e->get_arg(i), new_v);
ctx.new_value_eh(e->get_arg(i));
return;
}
}
if (is_true)
return;
if (sz == 1) {
ctx.flip(bv);
return;
}
unsigned i = ctx.rand(sz);
unsigned j = ctx.rand(sz-1);
if (j == i)
++j;
if (ctx.rand(2) == 0)
std::swap(i, j);
set_eval0(e->get_arg(i), eval0(e->get_arg(j)));
}
void datatype_plugin::repair_up(app* e) {
IF_VERBOSE(2, verbose_stream() << "dt-repair-up " << mk_bounded_pp(e, m) << "\n");
expr* t;
auto v0 = eval0(e);
auto v1 = eval1(e);
if (v0 == v1)
return;
if (dt.is_constructor(e))
set_eval0(e, v1);
else if (m.is_bool(e))
ctx.flip(ctx.atom2bool_var(e));
else if (dt.is_accessor(e, t))
repair_up_accessor(e, t, v1);
else {
UNREACHABLE();
}
}
void datatype_plugin::repair_up_accessor(app* e, expr* t, expr* v1) {
auto v_t = eval0(t);
auto f = e->get_decl();
SASSERT(dt.is_constructor(v_t));
auto c = dt.get_accessor_constructor(f);
if (to_app(v_t)->get_decl() != c)
update_eval_accessor(e, v_t, v1);
set_eval0(e, v1);
}
expr_ref datatype_plugin::eval1(expr* e) {
expr* s = nullptr, * t = nullptr;
if (m.is_eq(e, s, t))
return expr_ref(m.mk_bool_val(eval0rec(s) == eval0rec(t)), m);
if (m.is_distinct(e)) {
expr_ref_vector args(m);
for (auto arg : *to_app(e))
args.push_back(eval0(arg));
bool d = true;
for (unsigned i = 0; i < args.size(); ++i)
for (unsigned j = i + 1; i < args.size(); ++j)
d &= args.get(i) != args.get(j);
return expr_ref(m.mk_bool_val(d), m);
}
if (dt.is_accessor(e, t)) {
auto f = to_app(e)->get_decl();
auto v = eval0rec(t);
return eval_accessor(f, v);
}
if (dt.is_constructor(e)) {
expr_ref_vector args(m);
for (auto arg : *to_app(e))
args.push_back(eval0rec(arg));
return expr_ref(m.mk_app(to_app(e)->get_decl(), args), m);
}
if (dt.is_recognizer(e, t)) {
auto v = eval0rec(t);
SASSERT(dt.is_constructor(v));
auto c = dt.get_recognizer_constructor(to_app(e)->get_decl());
return expr_ref(m.mk_bool_val(c == to_app(v)->get_decl()), m);
}
return eval0(e);
}
expr_ref datatype_plugin::eval0rec(expr* e) {
auto v = m_eval.get(e->get_id(), nullptr);
if (v)
return expr_ref(v, m);
if (!is_app(e) || to_app(e)->get_family_id() != m_fid)
return ctx.get_value(e);
auto w = eval1(e);
m_eval.set(e->get_id(), w);
return w;
}
expr_ref datatype_plugin::eval_accessor(func_decl* f, expr* t) {
auto& t2val = m_eval_accessor[f];
if (!t2val.contains(t)) {
auto val = m_model->get_some_value(f->get_range());
m.inc_ref(t);
m.inc_ref(val);
}
return expr_ref(t2val[t], m);
}
void datatype_plugin::update_eval_accessor(app* e, expr* t, expr* value) {
func_decl* f = e->get_decl();
auto& t2val = m_eval_accessor[f];
expr* old_value = nullptr;
t2val.find(t, old_value);
if (old_value == value)
;
else if (old_value) {
t2val[t] = value;
m.inc_ref(value);
m.dec_ref(old_value);
}
else {
m.inc_ref(t);
m.inc_ref(value);
t2val.insert(t, value);
}
for (expr* b : m_occurs[f]) {
if (b == e)
continue;
expr* a;
VERIFY(dt.is_accessor(b, a));
auto v_a = eval0(a);
if (v_a.get() == t) {
set_eval0(b, value);
ctx.new_value_eh(b);
}
}
}
void datatype_plugin::del_eval_accessor() {
ptr_vector<expr> kv;
for (auto& [f, t2val] : m_eval_accessor)
for (auto& [k, val] : t2val)
kv.push_back(k), kv.push_back(val);
for (auto k : kv)
m.dec_ref(k);
}
expr_ref datatype_plugin::eval0(expr* n) {
if (!dt.is_datatype(n->get_sort()))
return ctx.get_value(n);
auto v = m_eval.get(n->get_id(), nullptr);
if (v)
return expr_ref(v, m);
set_eval0(n, m_model->get_some_value(n->get_sort()));
return expr_ref(m_eval.get(n->get_id()), m);
}
void datatype_plugin::set_eval0(expr* e, expr* value) {
if (dt.is_datatype(e->get_sort()))
m_eval[e->get_id()] = value;
else
ctx.set_value(e, value);
}
expr_ref datatype_plugin::eval0(euf::enode* n) {
return eval0(n->get_root()->get_expr());
}
void datatype_plugin::collect_statistics(statistics& st) const {
st.update("sls-dt-axioms", m_axioms.size());
st.update("sls-dt-occurs-conflicts", m_stats.m_num_occurs);
}
void datatype_plugin::reset_statistics() {}
}

107
src/ast/sls/sls_datatype_plugin.h Normal file
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/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
sls_datatype_plugin.h
Abstract:
Algebraic Datatypes for SLS
Author:
Nikolaj Bjorner (nbjorner) 2024-10-14
--*/
#pragma once
#include "ast/sls/sls_context.h"
#include "ast/datatype_decl_plugin.h"
#include "util/top_sort.h"
namespace sls {
class euf_plugin;
class datatype_plugin : public plugin {
struct stats {
unsigned m_num_occurs = 0;
void reset() { memset(this, 0, sizeof(*this)); }
};
struct parent_t {
expr* parent;
expr_ref condition;
};
euf_plugin& euf;
scoped_ptr<euf::egraph>& g;
obj_map<sort, ptr_vector<expr>> m_dts;
obj_map<expr, vector<parent_t>> m_parents;
bool m_axiomatic_mode = true;
mutable datatype_util dt;
expr_ref_vector m_axioms, m_values, m_eval;
model_ref m_model;
stats m_stats;
void collect_path_axioms();
void add_edge(expr* child, expr* parent, expr* cond);
void add_path_axioms();
void add_path_axioms(ptr_vector<expr>& children, sat::literal_vector& lits, vector<parent_t> const& parents);
void add_axioms();
void init_values();
void add_dep(euf::enode* n, top_sort<euf::enode>& dep);
euf::enode* get_constructor(euf::enode* n) const;
// f -> v_t -> val
// e = A(t)
// val(t) <- val
//
typedef obj_hashtable<expr> expr_set;
obj_map<func_decl, obj_map<expr, expr*>> m_eval_accessor;
obj_map<func_decl, expr_set> m_occurs;
expr_ref eval1(expr* e);
expr_ref eval0(euf::enode* n);
expr_ref eval0(expr* n);
expr_ref eval0rec(expr* n);
expr_ref eval_accessor(func_decl* f, expr* t);
void update_eval_accessor(app* e, expr* t, expr* value);
void del_eval_accessor();
void set_eval0(expr* e, expr* val);
void repair_down_constructor(app* e, expr* v0, expr* v1);
void repair_down_accessor(app* e, expr* t, expr* v1);
void repair_down_recognizer(app* e, expr* t);
void repair_down_eq(app* e, expr* s, expr* t);
void repair_down_distinct(app* e);
void repair_up_accessor(app* e, expr* t, expr* v0);
void propagate_literal_model_building(sat::literal lit);
public:
datatype_plugin(context& c);
~datatype_plugin() override;
family_id fid() override { return m_fid; }
expr_ref get_value(expr* e) override;
void initialize() override;
void start_propagation() override;
void propagate_literal(sat::literal lit) override;
bool propagate() override;
bool is_sat() override;
void register_term(expr* e) override;
bool set_value(expr* e, expr* v) override { return false; }
void repair_literal(sat::literal lit) override {}
bool include_func_interp(func_decl* f) const override;
bool repair_down(app* e) override;
void repair_up(app* e) override;
std::ostream& display(std::ostream& out) const override;
void collect_statistics(statistics& st) const override;
void reset_statistics() override;
};
}

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/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
sls_euf_plugin.cpp
Abstract:
Congruence Closure for SLS
Author:
Nikolaj Bjorner (nbjorner) 2024-06-24
Todo:
- try incremental CC with backtracking for changing assignments
- try determining plateau moves.
- try generally a model rotation move.
--*/
#include "ast/sls/sls_euf_plugin.h"
#include "ast/ast_ll_pp.h"
#include "ast/ast_pp.h"
#include "params/sls_params.hpp"
namespace sls {
euf_plugin::euf_plugin(context& c):
plugin(c),
m_values(8U, value_hash(*this), value_eq(*this)) {
m_fid = user_sort_family_id;
}
euf_plugin::~euf_plugin() {}
void euf_plugin::initialize() {
sls_params sp(ctx.get_params());
m_incremental_mode = sp.euf_incremental();
m_incremental = 1 == m_incremental_mode;
IF_VERBOSE(2, verbose_stream() << "sls.euf: incremental " << m_incremental_mode << "\n");
}
void euf_plugin::start_propagation() {
if (m_incremental_mode == 2)
m_incremental = !m_incremental;
m_g = alloc(euf::egraph, m);
std::function<void(std::ostream&, void*)> dj = [&](std::ostream& out, void* j) {
out << "lit " << to_literal(reinterpret_cast<size_t*>(j));
};
m_g->set_display_justification(dj);
init_egraph(*m_g, !m_incremental);
}
void euf_plugin::register_term(expr* e) {
if (!is_app(e))
return;
if (!is_uninterp(e))
return;
app* a = to_app(e);
if (a->get_num_args() == 0)
return;
auto f = a->get_decl();
if (!m_app.contains(f))
m_app.insert(f, ptr_vector<app>());
m_app[f].push_back(a);
}
unsigned euf_plugin::value_hash::operator()(app* t) const {
unsigned r = 0;
for (auto arg : *t)
r *= 3, r += cc.ctx.get_value(arg)->hash();
return r;
}
bool euf_plugin::value_eq::operator()(app* a, app* b) const {
SASSERT(a->get_num_args() == b->get_num_args());
for (unsigned i = a->get_num_args(); i-- > 0; )
if (cc.ctx.get_value(a->get_arg(i)) != cc.ctx.get_value(b->get_arg(i)))
return false;
return true;
}
void euf_plugin::propagate_literal_incremental(sat::literal lit) {
m_replay_stack.push_back(lit);
replay();
}
sat::literal euf_plugin::resolve_conflict() {
auto& g = *m_g;
SASSERT(g.inconsistent());
++m_stats.m_num_conflicts;
unsigned n = 0;
sat::literal_vector lits;
sat::literal flit = sat::null_literal;
ptr_vector<size_t> explain;
g.begin_explain();
g.explain<size_t>(explain, nullptr);
g.end_explain();
double reward = -1;
TRACE("enf",
for (auto p : explain) {
sat::literal l = to_literal(p);
tout << l << " " << mk_pp(ctx.atom(l.var()), m) << " " << ctx.is_unit(l) << "\n";
});
for (auto p : explain) {
sat::literal l = to_literal(p);
CTRACE("euf", !ctx.is_true(l), tout << "not true " << l << "\n"; ctx.display(tout););
SASSERT(ctx.is_true(l));
if (ctx.is_unit(l))
continue;
if (!lits.contains(~l))
lits.push_back(~l);
if (ctx.reward(l.var()) > reward)
n = 0, reward = ctx.reward(l.var());
if (ctx.rand(++n) == 0)
flit = l;
}
// flip the last literal on the replay stack
IF_VERBOSE(10, verbose_stream() << "sls.euf - flip " << flit << "\n");
ctx.add_clause(lits);
return flit;
}
void euf_plugin::resolve() {
auto& g = *m_g;
if (!g.inconsistent())
return;
auto flit = resolve_conflict();
sat::literal slit;
if (flit == sat::null_literal)
return;
do {
slit = m_stack.back();
g.pop(1);
m_replay_stack.push_back(slit);
m_stack.pop_back();
}
while (slit != flit);
ctx.flip(flit.var());
m_replay_stack.back().neg();
}
void euf_plugin::replay() {
while (!m_replay_stack.empty()) {
auto l = m_replay_stack.back();
m_replay_stack.pop_back();
propagate_literal_incremental_step(l);
if (m_g->inconsistent())
resolve();
}
}
void euf_plugin::propagate_literal_incremental_step(sat::literal lit) {
SASSERT(ctx.is_true(lit));
auto e = ctx.atom(lit.var());
expr* x, * y;
auto& g = *m_g;
if (!e)
return;
TRACE("euf", tout << "propagate " << lit << "\n");
m_stack.push_back(lit);
g.push();
if (m.is_eq(e, x, y)) {
if (lit.sign())
g.new_diseq(g.find(e), to_ptr(lit));
else
g.merge(g.find(x), g.find(y), to_ptr(lit));
g.merge(g.find(e), g.find(m.mk_bool_val(!lit.sign())), to_ptr(lit));
}
else if (!lit.sign() && m.is_distinct(e)) {
auto n = to_app(e)->get_num_args();
for (unsigned i = 0; i < n; ++i) {
expr* a = to_app(e)->get_arg(i);
for (unsigned j = i + 1; j < n; ++j) {
auto b = to_app(e)->get_arg(j);
expr_ref eq(m.mk_eq(a, b), m);
auto c = g.find(eq);
if (!c) {
euf::enode* args[2] = { g.find(a), g.find(b) };
c = g.mk(eq, 0, 2, args);
}
g.new_diseq(c, to_ptr(lit));
g.merge(c, g.find(m.mk_false()), to_ptr(lit));
}
}
}
// else if (m.is_bool(e) && is_app(e) && to_app(e)->get_family_id() == basic_family_id)
// ;
else {
auto a = g.find(e);
auto b = g.find(m.mk_bool_val(!lit.sign()));
g.merge(a, b, to_ptr(lit));
}
g.propagate();
}
void euf_plugin::propagate_literal(sat::literal lit) {
if (m_incremental)
propagate_literal_incremental(lit);
else
propagate_literal_non_incremental(lit);
}
void euf_plugin::propagate_literal_non_incremental(sat::literal lit) {
SASSERT(ctx.is_true(lit));
auto e = ctx.atom(lit.var());
expr* x, * y;
if (!e)
return;
auto block = [&](euf::enode* a, euf::enode* b) {
TRACE("euf", tout << "block " << m_g->bpp(a) << " != " << m_g->bpp(b) << "\n");
if (a->get_root() != b->get_root())
return;
ptr_vector<size_t> explain;
m_g->explain_eq<size_t>(explain, nullptr, a, b);
m_g->end_explain();
unsigned n = 1;
sat::literal_vector lits;
sat::literal flit = sat::null_literal;
if (!ctx.is_unit(lit)) {
flit = lit;
lits.push_back(~lit);
}
for (auto p : explain) {
sat::literal l = to_literal(p);
if (!ctx.is_true(l))
return;
if (ctx.is_unit(l))
continue;
lits.push_back(~l);
if (ctx.rand(++n) == 0)
flit = l;
}
ctx.add_clause(lits);
++m_stats.m_num_conflicts;
if (flit != sat::null_literal)
ctx.flip(flit.var());
};
if (lit.sign() && m.is_eq(e, x, y))
block(m_g->find(x), m_g->find(y));
else if (!lit.sign() && m.is_distinct(e)) {
auto n = to_app(e)->get_num_args();
for (unsigned i = 0; i < n; ++i) {
auto a = m_g->find(to_app(e)->get_arg(i));
for (unsigned j = i + 1; j < n; ++j) {
auto b = m_g->find(to_app(e)->get_arg(j));
block(a, b);
}
}
}
else if (lit.sign()) {
auto a = m_g->find(e);
auto b = m_g->find(m.mk_true());
block(a, b);
}
}
void euf_plugin::init_egraph(euf::egraph& g, bool merge_eqs) {
ptr_vector<euf::enode> args;
m_stack.reset();
for (auto t : ctx.subterms()) {
args.reset();
if (is_app(t))
for (auto* arg : *to_app(t))
args.push_back(g.find(arg));
g.mk(t, 0, args.size(), args.data());
}
if (!g.find(m.mk_true()))
g.mk(m.mk_true(), 0, 0, nullptr);
if (!g.find(m.mk_false()))
g.mk(m.mk_false(), 0, 0, nullptr);
// merge all equalities
// check for conflict with disequalities during propagation
if (merge_eqs) {
TRACE("euf", tout << "root literals " << ctx.root_literals() << "\n");
for (auto lit : ctx.root_literals()) {
if (!ctx.is_true(lit))
lit.neg();
auto e = ctx.atom(lit.var());
expr* x, * y;
if (e && m.is_eq(e, x, y) && !lit.sign())
g.merge(g.find(x), g.find(y), to_ptr(lit));
else if (!lit.sign())
g.merge(g.find(e), g.find(m.mk_true()), to_ptr(lit));
}
g.propagate();
if (g.inconsistent())
resolve_conflict();
}
typedef obj_map<sort, unsigned> map1;
typedef obj_map<euf::enode, expr*> map2;
m_num_elems = alloc(map1);
m_root2value = alloc(map2);
m_pinned = alloc(expr_ref_vector, m);
for (auto n : g.nodes()) {
if (n->is_root() && is_user_sort(n->get_sort())) {
// verbose_stream() << "init root " << g.pp(n) << "\n";
unsigned num = 0;
m_num_elems->find(n->get_sort(), num);
expr* v = m.mk_model_value(num, n->get_sort());
m_pinned->push_back(v);
m_root2value->insert(n, v);
m_num_elems->insert(n->get_sort(), num + 1);
}
}
}
expr_ref euf_plugin::get_value(expr* e) {
if (m.is_model_value(e))
return expr_ref(e, m);
if (!m_g) {
m_g = alloc(euf::egraph, m);
init_egraph(*m_g, true);
}
auto n = m_g->find(e)->get_root();
VERIFY(m_root2value->find(n, e));
return expr_ref(e, m);
}
bool euf_plugin::include_func_interp(func_decl* f) const {
return is_uninterp(f) && f->get_arity() > 0;
}
bool euf_plugin::is_sat() {
for (auto& [f, ts] : m_app) {
if (ts.size() <= 1)
continue;
m_values.reset();
for (auto* t : ts) {
app* u;
if (!ctx.is_relevant(t))
continue;
if (m_values.find(t, u)) {
if (ctx.get_value(t) != ctx.get_value(u))
return false;
}
else
m_values.insert(t);
}
}
// validate_model();
return true;
}
void euf_plugin::validate_model() {
auto& g = *m_g;
for (auto lit : ctx.root_literals()) {
euf::enode* a, * b;
if (!ctx.is_true(lit))
continue;
auto e = ctx.atom(lit.var());
if (!e)
continue;
if (!ctx.is_relevant(e))
continue;
if (m.is_distinct(e))
continue;
if (m.is_eq(e)) {
a = g.find(to_app(e)->get_arg(0));
b = g.find(to_app(e)->get_arg(1));
}
if (lit.sign() && m.is_eq(e)) {
if (a->get_root() == b->get_root()) {
IF_VERBOSE(0, verbose_stream() << "not disequal " << lit << " " << mk_pp(e, m) << "\n");
ctx.display(verbose_stream());
UNREACHABLE();
}
}
else if (!lit.sign() && m.is_eq(e)) {
if (a->get_root() != b->get_root()) {
IF_VERBOSE(0, verbose_stream() << "not equal " << lit << " " << mk_pp(e, m) << "\n");
//UNREACHABLE();
}
}
else if (to_app(e)->get_family_id() != basic_family_id && lit.sign() && g.find(e)->get_root() != g.find(m.mk_false())->get_root()) {
IF_VERBOSE(0, verbose_stream() << "not alse " << lit << " " << mk_pp(e, m) << "\n");
//UNREACHABLE();
}
else if (to_app(e)->get_family_id() != basic_family_id && !lit.sign() && g.find(e)->get_root() != g.find(m.mk_true())->get_root()) {
IF_VERBOSE(0, verbose_stream() << "not true " << lit << " " << mk_pp(e, m) << "\n");
//UNREACHABLE();
}
}
}
bool euf_plugin::propagate() {
bool new_constraint = false;
for (auto & [f, ts] : m_app) {
if (ts.size() <= 1)
continue;
m_values.reset();
for (auto * t : ts) {
app* u;
if (!ctx.is_relevant(t))
continue;
if (m_values.find(t, u)) {
if (ctx.get_value(t) == ctx.get_value(u))
continue;
expr_ref_vector ors(m);
for (unsigned i = t->get_num_args(); i-- > 0; )
ors.push_back(m.mk_not(m.mk_eq(t->get_arg(i), u->get_arg(i))));
ors.push_back(m.mk_eq(t, u));
#if 0
verbose_stream() << "conflict: " << mk_bounded_pp(t, m) << " != " << mk_bounded_pp(u, m) << "\n";
verbose_stream() << "value " << ctx.get_value(t) << " != " << ctx.get_value(u) << "\n";
for (unsigned i = t->get_num_args(); i-- > 0; )
verbose_stream() << ctx.get_value(t->get_arg(i)) << " == " << ctx.get_value(u->get_arg(i)) << "\n";
#endif
expr_ref fml(m.mk_or(ors), m);
ctx.add_constraint(fml);
new_constraint = true;
}
else
m_values.insert(t);
}
}
for (auto lit : ctx.root_literals()) {
if (!ctx.is_true(lit))
continue;
auto e = ctx.atom(lit.var());
if (lit.sign() && e && m.is_distinct(e)) {
auto n = to_app(e)->get_num_args();
expr_ref_vector eqs(m);
for (unsigned i = 0; i < n; ++i) {
auto a = m_g->find(to_app(e)->get_arg(i));
for (unsigned j = i + 1; j < n; ++j) {
auto b = m_g->find(to_app(e)->get_arg(j));
if (a->get_root() == b->get_root())
goto done_distinct;
eqs.push_back(m.mk_eq(a->get_expr(), b->get_expr()));
}
}
// distinct(a, b, c) or a = b or a = c or b = c
eqs.push_back(e);
ctx.add_constraint(m.mk_or(eqs));
new_constraint = true;
done_distinct:
;
}
}
return new_constraint;
}
std::ostream& euf_plugin::display(std::ostream& out) const {
if (m_g)
m_g->display(out);
for (auto& [f, ts] : m_app) {
for (auto* t : ts)
out << mk_bounded_pp(t, m) << "\n";
out << "\n";
}
return out;
}
void euf_plugin::collect_statistics(statistics& st) const {
st.update("sls-euf-conflict", m_stats.m_num_conflicts);
}
void euf_plugin::reset_statistics() {
m_stats.reset();
}
}

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/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
sls_euf_plugin.h
Abstract:
Congruence Closure for SLS
Author:
Nikolaj Bjorner (nbjorner) 2024-06-24
--*/
#pragma once
#include "util/hashtable.h"
#include "ast/sls/sls_context.h"
#include "ast/euf/euf_egraph.h"
namespace sls {
class euf_plugin : public plugin {
struct stats {
unsigned m_num_conflicts = 0;
void reset() { memset(this, 0, sizeof(*this)); }
};
obj_map<func_decl, ptr_vector<app>> m_app;
struct value_hash {
euf_plugin& cc;
value_hash(euf_plugin& cc) : cc(cc) {}
unsigned operator()(app* t) const;
};
struct value_eq {
euf_plugin& cc;
value_eq(euf_plugin& cc) : cc(cc) {}
bool operator()(app* a, app* b) const;
};
hashtable<app*, value_hash, value_eq> m_values;
bool m_incremental = false;
unsigned m_incremental_mode = 0;
stats m_stats;
scoped_ptr<euf::egraph> m_g;
scoped_ptr<obj_map<sort, unsigned>> m_num_elems;
scoped_ptr<obj_map<euf::enode, expr*>> m_root2value;
scoped_ptr<expr_ref_vector> m_pinned;
void init_egraph(euf::egraph& g, bool merge_eqs);
sat::literal_vector m_stack, m_replay_stack;
void propagate_literal_incremental(sat::literal lit);
void propagate_literal_incremental_step(sat::literal lit);
void resolve();
sat::literal resolve_conflict();
void replay();
void propagate_literal_non_incremental(sat::literal lit);
bool is_user_sort(sort* s) { return s->get_family_id() == user_sort_family_id; }
size_t* to_ptr(sat::literal l) { return reinterpret_cast<size_t*>((size_t)(l.index() << 4)); };
sat::literal to_literal(size_t* p) { return sat::to_literal(static_cast<unsigned>(reinterpret_cast<size_t>(p) >> 4)); };
void validate_model();
public:
euf_plugin(context& c);
~euf_plugin() override;
expr_ref get_value(expr* e) override;
void initialize() override;
void start_propagation() override;
void propagate_literal(sat::literal lit) override;
bool propagate() override;
bool is_sat() override;
void register_term(expr* e) override;
std::ostream& display(std::ostream& out) const override;
bool set_value(expr* e, expr* v) override { return false; }
bool include_func_interp(func_decl* f) const override;
void repair_up(app* e) override {}
bool repair_down(app* e) override { return false; }
void repair_literal(sat::literal lit) override {}
void collect_statistics(statistics& st) const override;
void reset_statistics() override;
scoped_ptr<euf::egraph>& egraph() { return m_g; }
};
}

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/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
sls_smt_plugin.cpp
Abstract:
A Stochastic Local Search (SLS) Plugin.
Author:
Nikolaj Bjorner (nbjorner) 2024-07-10
--*/
#include "ast/sls/sls_smt_plugin.h"
#include "ast/for_each_expr.h"
#include "ast/bv_decl_plugin.h"
namespace sls {
smt_plugin::smt_plugin(smt_context& ctx) :
ctx(ctx),
m(ctx.get_manager()),
m_sls(),
m_sync(),
m_smt2sync_tr(m, m_sync),
m_smt2sls_tr(m, m_sls),
m_sync_uninterp(m_sync),
m_sls_uninterp(m_sls),
m_sync_values(m_sync),
m_context(m_sls, *this)
{
}
smt_plugin::~smt_plugin() {
SASSERT(!m_ddfw);
}
void smt_plugin::check(expr_ref_vector const& fmls, vector <sat::literal_vector> const& clauses) {
SASSERT(!m_ddfw);
// set up state for local search theory_sls here
m_result = l_undef;
m_completed = false;
m_units.reset();
m_has_units = false;
m_sls_model = nullptr;
m_ddfw = alloc(sat::ddfw);
m_ddfw->set_plugin(this);
m_ddfw->updt_params(ctx.get_params());
for (auto const& clause : clauses) {
m_ddfw->add(clause.size(), clause.data());
for (auto lit : clause)
add_shared_var(lit.var(), lit.var());
}
for (auto v : m_shared_bool_vars) {
expr* e = ctx.bool_var2expr(v);
if (!e)
continue;
m_context.register_atom(v, m_smt2sls_tr(e));
for (auto t : subterms::all(expr_ref(e, m)))
add_shared_term(t);
}
for (auto fml : fmls)
m_context.add_constraint(m_smt2sls_tr(fml));
for (unsigned v = 0; v < ctx.get_num_bool_vars(); ++v) {
expr* e = ctx.bool_var2expr(v);
if (!e)
continue;
expr_ref sls_e(m_sls);
sls_e = m_smt2sls_tr(e);
auto w = m_context.atom2bool_var(sls_e);
if (w == sat::null_bool_var)
continue;
add_shared_var(v, w);
for (auto t : subterms::all(expr_ref(e, m)))
add_shared_term(t);
}
m_thread = std::thread([this]() { run(); });
}
void smt_plugin::run() {
if (!m_ddfw)
return;
m_result = m_ddfw->check(0, nullptr);
m_ddfw->collect_statistics(m_st);
IF_VERBOSE(1, verbose_stream() << "sls-result " << m_result << "\n");
m_completed = true;
}
void smt_plugin::finalize(model_ref& mdl, ::statistics& st) {
auto* d = m_ddfw;
if (!d)
return;
bool canceled = !m_completed;
IF_VERBOSE(3, verbose_stream() << "finalize\n");
if (!m_completed)
d->rlimit().cancel();
if (m_thread.joinable())
m_thread.join();
SASSERT(m_completed);
st.copy(m_st);
mdl = nullptr;
if (m_result == l_true && m_sls_model) {
ast_translation tr(m_sls, m);
mdl = m_sls_model->translate(tr);
TRACE("sls", tout << "model: " << *m_sls_model << "\n";);
if (!canceled)
ctx.set_finished();
}
m_ddfw = nullptr;
// m_ddfw owns the pointer to smt_plugin and destructs it.
dealloc(d);
}
std::ostream& smt_plugin::display(std::ostream& out) {
m_ddfw->display(out);
m_context.display(out);
return out;
}
bool smt_plugin::is_shared(sat::literal lit) {
auto w = m_smt_bool_var2sls_bool_var.get(lit.var(), sat::null_bool_var);
if (w != sat::null_bool_var)
return true;
auto e = ctx.bool_var2expr(lit.var());
expr* t = nullptr;
if (!e)
return false;
bv_util bv(m);
if (bv.is_bit2bool(e, t) && m_shared_terms.contains(t->get_id())) {
verbose_stream() << "shared bit2bool " << mk_bounded_pp(e, ctx.get_manager()) << "\n";
return true;
}
// if arith.is_le(e, s, t) && t is a numeral, s is shared-term....
return false;
}
void smt_plugin::add_shared_var(sat::bool_var v, sat::bool_var w) {
m_smt_bool_var2sls_bool_var.setx(v, w, sat::null_bool_var);
m_sls_bool_var2smt_bool_var.setx(w, v, sat::null_bool_var);
m_sls_phase.reserve(v + 1);
m_sat_phase.reserve(v + 1);
m_rewards.reserve(v + 1);
m_shared_bool_vars.insert(v);
}
void smt_plugin::add_unit(sat::literal lit) {
if (!is_shared(lit))
return;
std::lock_guard<std::mutex> lock(m_mutex);
m_units.push_back(lit);
m_has_units = true;
}
void smt_plugin::import_phase_from_smt() {
if (m_has_new_sat_phase)
return;
m_has_new_sat_phase = true;
IF_VERBOSE(3, verbose_stream() << "new SMT -> SLS phase\n");
ctx.set_has_new_best_phase(false);
std::lock_guard<std::mutex> lock(m_mutex);
for (auto v : m_shared_bool_vars)
m_sat_phase[v] = ctx.get_best_phase(v);
}
bool smt_plugin::export_to_sls() {
bool updated = false;
if (export_units_to_sls())
updated = true;
if (export_phase_to_sls())
updated = true;
return updated;
}
bool smt_plugin::export_phase_to_sls() {
if (!m_has_new_sat_phase)
return false;
std::lock_guard<std::mutex> lock(m_mutex);
IF_VERBOSE(3, verbose_stream() << "SMT -> SLS phase\n");
for (auto v : m_shared_bool_vars) {
auto w = m_smt_bool_var2sls_bool_var[v];
if (m_sat_phase[v] != is_true(sat::literal(w, false)))
flip(w);
m_ddfw->bias(w) = m_sat_phase[v] ? 1 : -1;
}
m_has_new_sat_phase = false;
return true;
}
bool smt_plugin::export_units_to_sls() {
if (!m_has_units)
return false;
std::lock_guard<std::mutex> lock(m_mutex);
IF_VERBOSE(2, verbose_stream() << "SMT -> SLS units " << m_units << "\n");
for (auto lit : m_units) {
auto v = lit.var();
if (m_shared_bool_vars.contains(v)) {
auto w = m_smt_bool_var2sls_bool_var[v];
sat::literal sls_lit(w, lit.sign());
IF_VERBOSE(10, verbose_stream() << "unit " << sls_lit << "\n");
m_ddfw->add(1, &sls_lit);
}
else {
IF_VERBOSE(0, verbose_stream() << "value restriction " << lit << " "
<< mk_bounded_pp(ctx.bool_var2expr(lit.var()), m) << "\n");
}
}
m_has_units = false;
m_units.reset();
return true;
}
void smt_plugin::export_from_sls() {
if (unsat().size() > m_min_unsat_size)
return;
m_min_unsat_size = unsat().size();
std::lock_guard<std::mutex> lock(m_mutex);
for (auto v : m_shared_bool_vars) {
auto w = m_smt_bool_var2sls_bool_var[v];
m_rewards[v] = m_ddfw->get_reward_avg(w);
//verbose_stream() << v << " " << w << "\n";
VERIFY(m_ddfw->get_model().size() > w);
VERIFY(m_sls_phase.size() > v);
m_sls_phase[v] = l_true == m_ddfw->get_model()[w];
m_has_new_sls_phase = true;
}
// export_values_from_sls();
}
void smt_plugin::export_values_from_sls() {
IF_VERBOSE(3, verbose_stream() << "import values from sls\n");
std::lock_guard<std::mutex> lock(m_mutex);
for (auto const& [t, t_sync] : m_sls2sync_uninterp) {
expr_ref val_t = m_context.get_value(t_sync);
m_sync_values.set(t_sync->get_id(), val_t.get());
}
m_has_new_sls_values = true;
}
void smt_plugin::import_from_sls() {
export_activity_to_smt();
export_values_to_smt();
export_phase_to_smt();
}
void smt_plugin::export_activity_to_smt() {
}
void smt_plugin::export_values_to_smt() {
if (!m_has_new_sls_values)
return;
IF_VERBOSE(3, verbose_stream() << "SLS -> SMT values\n");
std::lock_guard<std::mutex> lock(m_mutex);
ast_translation tr(m_sync, m);
for (auto const& [t, t_sync] : m_smt2sync_uninterp) {
expr* sync_val = m_sync_values.get(t_sync->get_id(), nullptr);
if (!sync_val)
continue;
expr_ref val(tr(sync_val), m);
ctx.initialize_value(t, val);
}
m_has_new_sls_values = false;
}
void smt_plugin::export_phase_to_smt() {
if (!m_has_new_sls_phase)
return;
std::lock_guard<std::mutex> lock(m_mutex);
IF_VERBOSE(3, verbose_stream() << "SLS -> SMT phase\n");
for (auto v : m_shared_bool_vars) {
auto w = m_smt_bool_var2sls_bool_var[v];
ctx.force_phase(sat::literal(w, m_sls_phase[v]));
}
m_has_new_sls_phase = false;
}
void smt_plugin::add_shared_term(expr* t) {
m_shared_terms.insert(t->get_id());
if (is_uninterp(t))
add_uninterp(t);
}
void smt_plugin::add_uninterp(expr* smt_t) {
auto sync_t = m_smt2sync_tr(smt_t);
auto sls_t = m_smt2sls_tr(smt_t);
m_sync_uninterp.push_back(sync_t);
m_sls_uninterp.push_back(sls_t);
m_smt2sync_uninterp.insert(smt_t, sync_t);
m_sls2sync_uninterp.insert(sls_t, sync_t);
}
void smt_plugin::on_save_model() {
TRACE("sls", display(tout));
while (unsat().empty()) {
m_context.check();
if (!m_new_clause_added)
break;
m_ddfw->reinit();
m_new_clause_added = false;
}
// export_from_sls();
}
}

158
src/ast/sls/sls_smt_plugin.h Normal file
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@ -0,0 +1,158 @@
/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
sls_smt_plugin.h
Abstract:
A Stochastic Local Search (SLS) Plugin.
Author:
Nikolaj Bjorner (nbjorner) 2024-07-10
--*/
#pragma once
#include "ast/sls/sls_context.h"
#include "ast/sls/sat_ddfw.h"
#include "util/statistics.h"
#include <thread>
#include <mutex>
namespace sls {
class smt_context {
public:
virtual ~smt_context() {}
virtual ast_manager& get_manager() = 0;
virtual params_ref get_params() = 0;
virtual void initialize_value(expr* t, expr* v) = 0;
virtual void force_phase(sat::literal lit) = 0;
virtual void set_has_new_best_phase(bool b) = 0;
virtual bool get_best_phase(sat::bool_var v) = 0;
virtual expr* bool_var2expr(sat::bool_var v) = 0;
virtual void set_finished() = 0;
virtual unsigned get_num_bool_vars() const = 0;
};
//
// m is accessed by the main thread
// m_sls is accessed by the sls thread
// m_sync is accessed by both
//
class smt_plugin : public sat::local_search_plugin, public sat_solver_context {
smt_context& ctx;
ast_manager& m;
ast_manager m_sls;
ast_manager m_sync;
ast_translation m_smt2sync_tr, m_smt2sls_tr;
expr_ref_vector m_sync_uninterp, m_sls_uninterp;
expr_ref_vector m_sync_values;
sat::ddfw* m_ddfw = nullptr;
sls::context m_context;
std::atomic<lbool> m_result;
std::atomic<bool> m_completed, m_has_units;
std::thread m_thread;
std::mutex m_mutex;
sat::literal_vector m_units;
model_ref m_sls_model;
::statistics m_st;
bool m_new_clause_added = false;
unsigned m_min_unsat_size = UINT_MAX;
obj_map<expr, expr*> m_sls2sync_uninterp; // hashtable from sls-uninterp to sync uninterp
obj_map<expr, expr*> m_smt2sync_uninterp; // hashtable from external uninterp to sync uninterp
std::atomic<bool> m_has_new_sls_values = false;
uint_set m_shared_bool_vars, m_shared_terms;
svector<bool> m_sat_phase;
std::atomic<bool> m_has_new_sat_phase = false;
std::atomic<bool> m_has_new_sls_phase = false;
svector<bool> m_sls_phase;
svector<double> m_rewards;
svector<sat::bool_var> m_smt_bool_var2sls_bool_var, m_sls_bool_var2smt_bool_var;
bool is_shared(sat::literal lit);
void run();
void add_shared_term(expr* t);
void add_uninterp(expr* smt_t);
void add_shared_var(sat::bool_var v, sat::bool_var w);
void import_phase_from_smt();
void import_values_from_sls();
void export_values_from_sls();
void import_activity_from_sls();
bool export_phase_to_sls();
bool export_units_to_sls();
void export_values_to_smt();
void export_activity_to_smt();
void export_phase_to_smt();
void export_from_sls();
friend class sat::ddfw;
~smt_plugin();
public:
smt_plugin(smt_context& ctx);
// interface to calling solver:
void check(expr_ref_vector const& fmls, vector <sat::literal_vector> const& clauses);
void finalize(model_ref& md, ::statistics& st);
void updt_params(params_ref& p) {}
std::ostream& display(std::ostream& out) override;
bool export_to_sls();
void import_from_sls();
bool completed() { return m_completed; }
void add_unit(sat::literal lit);
// local_search_plugin:
void on_restart() override {
if (export_to_sls())
m_ddfw->reinit();
}
void on_save_model() override;
void on_model(model_ref& mdl) override {
IF_VERBOSE(3, verbose_stream() << "on-model " << "\n");
m_sls_model = mdl;
}
void init_search() override {}
void finish_search() override {}
void on_rescale() override {}
// sat_solver_context:
vector<sat::clause_info> const& clauses() const override { return m_ddfw->clauses(); }
sat::clause_info const& get_clause(unsigned idx) const override { return m_ddfw->get_clause_info(idx); }
ptr_iterator<unsigned> get_use_list(sat::literal lit) override { return m_ddfw->use_list(lit); }
void flip(sat::bool_var v) override {
m_ddfw->flip(v);
}
double reward(sat::bool_var v) override { return m_ddfw->get_reward(v); }
double get_weigth(unsigned clause_idx) override { return m_ddfw->get_clause_info(clause_idx).m_weight; }
bool is_true(sat::literal lit) override {
return m_ddfw->get_value(lit.var()) != lit.sign();
}
unsigned num_vars() const override { return m_ddfw->num_vars(); }
indexed_uint_set const& unsat() const override { return m_ddfw->unsat_set(); }
sat::bool_var add_var() override {
return m_ddfw->add_var();
}
void add_clause(unsigned n, sat::literal const* lits) override {
m_ddfw->add(n, lits);
m_new_clause_added = true;
}
void force_restart() override { m_ddfw->force_restart(); }
};
}

171
src/ast/sls/sls_smt_solver.cpp Normal file
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@ -0,0 +1,171 @@
/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
sls_smt_solver.cpp
Abstract:
A Stochastic Local Search (SLS) Solver.
Author:
Nikolaj Bjorner (nbjorner) 2024-07-10
--*/
#include "ast/sls/sls_context.h"
#include "ast/sls/sat_ddfw.h"
#include "ast/sls/sls_smt_solver.h"
#include "ast/ast_ll_pp.h"
namespace sls {
class smt_solver::solver_ctx : public sat::local_search_plugin, public sls::sat_solver_context {
ast_manager& m;
sat::ddfw& m_ddfw;
context m_context;
bool m_dirty = false;
bool m_new_constraint = false;
model_ref m_model;
obj_map<expr, sat::literal> m_expr2lit;
public:
solver_ctx(ast_manager& m, sat::ddfw& d) :
m(m), m_ddfw(d), m_context(m, *this) {
m_ddfw.set_plugin(this);
m.limit().push_child(&m_ddfw.rlimit());
}
~solver_ctx() override {
m.limit().pop_child(&m_ddfw.rlimit());
}
void init_search() override {}
void finish_search() override {}
void on_rescale() override {}
void on_restart() override {
m_context.on_restart();
}
bool m_on_save_model = false;
void on_save_model() override {
if (m_on_save_model)
return;
flet<bool> _on_save_model(m_on_save_model, true);
CTRACE("sls", unsat().empty(), display(tout));
while (unsat().empty()) {
m_context.check();
if (!m_new_constraint)
break;
TRACE("sls", display(tout));
//m_ddfw.simplify();
m_ddfw.reinit();
m_new_constraint = false;
}
}
void on_model(model_ref& mdl) override {
IF_VERBOSE(1, verbose_stream() << "on-model " << "\n");
m_model = mdl;
}
void register_atom(sat::bool_var v, expr* e) {
m_context.register_atom(v, e);
}
std::ostream& display(std::ostream& out) override {
m_ddfw.display(out);
m_context.display(out);
return out;
}
vector<sat::clause_info> const& clauses() const override { return m_ddfw.clauses(); }
sat::clause_info const& get_clause(unsigned idx) const override { return m_ddfw.get_clause_info(idx); }
ptr_iterator<unsigned> get_use_list(sat::literal lit) override { return m_ddfw.use_list(lit); }
void flip(sat::bool_var v) override { if (m_dirty) m_ddfw.reinit(), m_dirty = false; m_ddfw.flip(v); }
double reward(sat::bool_var v) override { return m_ddfw.get_reward(v); }
double get_weigth(unsigned clause_idx) override { return m_ddfw.get_clause_info(clause_idx).m_weight; }
bool is_true(sat::literal lit) override { return m_ddfw.get_value(lit.var()) != lit.sign(); }
unsigned num_vars() const override { return m_ddfw.num_vars(); }
indexed_uint_set const& unsat() const override { return m_ddfw.unsat_set(); }
sat::bool_var add_var() override { m_dirty = true; return m_ddfw.add_var(); }
void add_clause(expr* f) { m_context.add_clause(f); }
void force_restart() override { m_ddfw.force_restart(); }
void add_clause(unsigned n, sat::literal const* lits) override {
m_ddfw.add(n, lits);
m_new_constraint = true;
}
sat::literal mk_literal() {
sat::bool_var v = add_var();
return sat::literal(v, false);
}
model_ref get_model() { return m_model; }
void collect_statistics(statistics& st) {
m_ddfw.collect_statistics(st);
m_context.collect_statistics(st);
}
void reset_statistics() {
m_ddfw.reset_statistics();
m_context.reset_statistics();
}
void updt_params(params_ref const& p) {
m_ddfw.updt_params(p);
m_context.updt_params(p);
}
};
smt_solver::smt_solver(ast_manager& m, params_ref const& p):
m(m),
m_solver_ctx(alloc(solver_ctx, m, m_ddfw)),
m_assertions(m) {
m_solver_ctx->updt_params(p);
}
smt_solver::~smt_solver() {
}
void smt_solver::assert_expr(expr* e) {
if (m.is_and(e)) {
for (expr* arg : *to_app(e))
assert_expr(arg);
}
else
m_assertions.push_back(e);
}
lbool smt_solver::check() {
for (auto f : m_assertions)
m_solver_ctx->add_clause(f);
IF_VERBOSE(10, m_solver_ctx->display(verbose_stream()));
return m_ddfw.check(0, nullptr);
}
model_ref smt_solver::get_model() {
return m_solver_ctx->get_model();
}
std::ostream& smt_solver::display(std::ostream& out) {
return m_solver_ctx->display(out);
}
void smt_solver::collect_statistics(statistics& st) {
m_solver_ctx->collect_statistics(st);
}
void smt_solver::reset_statistics() {
m_solver_ctx->reset_statistics();
}
}

44
src/ast/sls/sls_smt_solver.h Normal file
View file

@ -0,0 +1,44 @@
/*++
Copyright (c) 2024 Microsoft Corporation
Module Name:
sls_smt_solver.h
Abstract:
A Stochastic Local Search (SLS) Solver.
Author:
Nikolaj Bjorner (nbjorner) 2024-07-10
--*/
#pragma once
#include "ast/sls/sls_context.h"
#include "ast/sls/sat_ddfw.h"
namespace sls {
class smt_solver {
ast_manager& m;
class solver_ctx;
sat::ddfw m_ddfw;
solver_ctx* m_solver_ctx = nullptr;
expr_ref_vector m_assertions;
statistics m_st;
public:
smt_solver(ast_manager& m, params_ref const& p);
~smt_solver();
void assert_expr(expr* e);
lbool check();
model_ref get_model();
void updt_params(params_ref& p) {}
void collect_statistics(statistics& st);
std::ostream& display(std::ostream& out);
void reset_statistics();
};
}

2
src/math/hilbert/hilbert_basis.h
View file

@ -43,7 +43,7 @@ class hilbert_basis {
typedef vector<numeral> num_vector;
static checked_int64<check> to_numeral(rational const& r) {
if (!r.is_int64()) {
throw checked_int64<check>::overflow_exception();
throw overflow_exception();
}
return checked_int64<check>(r.get_int64());
}

3
src/model/model.cpp
View file

@ -39,6 +39,7 @@ Revision History:
#include "model/datatype_factory.h"
#include "model/numeral_factory.h"
#include "model/fpa_factory.h"
#include "model/char_factory.h"
model::model(ast_manager & m):
@ -103,12 +104,14 @@ value_factory* model::get_factory(sort* s) {
if (m_factories.plugins().empty()) {
seq_util su(m);
fpa_util fu(m);
m_factories.register_plugin(alloc(basic_factory, m, 0));
m_factories.register_plugin(alloc(array_factory, m, *this));
m_factories.register_plugin(alloc(datatype_factory, m, *this));
m_factories.register_plugin(alloc(bv_factory, m));
m_factories.register_plugin(alloc(arith_factory, m));
m_factories.register_plugin(alloc(seq_factory, m, su.get_family_id(), *this));
m_factories.register_plugin(alloc(fpa_value_factory, m, fu.get_family_id()));
//m_factories.register_plugin(alloc(char_factory, m, char_decl_plugin(m).get_family_id());
}
family_id fid = s->get_family_id();
return m_factories.get_plugin(fid);

2
src/opt/opt_context.cpp
View file

@ -42,7 +42,7 @@ Notes:
#include "ast/converters/generic_model_converter.h"
#include "ackermannization/ackermannize_bv_tactic.h"
#include "sat/sat_solver/inc_sat_solver.h"
#include "sat/sat_params.hpp"
#include "params/sat_params.hpp"
#include "opt/opt_context.h"
#include "opt/opt_solver.h"
#include "opt/opt_params.hpp"

2
src/opt/opt_lns.cpp
View file

@ -20,7 +20,7 @@ Author:
#include "ast/pb_decl_plugin.h"
#include "opt/maxsmt.h"
#include "opt/opt_lns.h"
#include "sat/sat_params.hpp"
#include "params/sat_params.hpp"
#include <algorithm>
namespace opt {

1
src/params/CMakeLists.txt
View file

@ -14,6 +14,7 @@ z3_add_component(params
pattern_inference_params_helper.pyg
poly_rewriter_params.pyg
rewriter_params.pyg
sat_params.pyg
seq_rewriter_params.pyg
sls_params.pyg
solver_params.pyg

0
src/sat/sat_params.pyg → src/params/sat_params.pyg
View file

2
src/params/sls_params.pyg
View file

@ -22,6 +22,8 @@ def_module_params('sls',
('early_prune', BOOL, 1, 'use early pruning for score prediction'),
('random_offset', BOOL, 1, 'use random offset for candidate evaluation'),
('rescore', BOOL, 1, 'rescore/normalize top-level score every base restart interval'),
('euf_incremental', UINT, 0, '0 non-incremental, 1 incremental, 2 alternating EUF resolver'),
('dt_axiomatic', BOOL, True, 'use axiomatic mode or model reduction for datatype solver'),
('track_unsat', BOOL, 0, 'keep a list of unsat assertions as done in SAT - currently disabled internally'),
('random_seed', UINT, 0, 'random seed')
))

15
src/qe/qe_mbp.cpp
View file

@ -42,7 +42,8 @@ Revision History:
using namespace qe;
namespace {
namespace qembp {
// rewrite select(store(a, i, k), j) into k if m \models i = j and select(a, j) if m \models i != j
struct rd_over_wr_rewriter : public default_rewriter_cfg {
ast_manager &m;
@ -124,19 +125,19 @@ namespace {
};
}
template class rewriter_tpl<app_const_arr_rewriter>;
template class rewriter_tpl<rd_over_wr_rewriter>;
template class rewriter_tpl<qembp::app_const_arr_rewriter>;
template class rewriter_tpl<qembp::rd_over_wr_rewriter>;
void rewrite_as_const_arr(expr* in, model& mdl, expr_ref& out) {
app_const_arr_rewriter cfg(out.m(), mdl);
rewriter_tpl<app_const_arr_rewriter> rw(out.m(), false, cfg);
qembp::app_const_arr_rewriter cfg(out.m(), mdl);
rewriter_tpl<qembp::app_const_arr_rewriter> rw(out.m(), false, cfg);
rw(in, out);
}
void rewrite_read_over_write(expr *in, model &mdl, expr_ref &out) {
rd_over_wr_rewriter cfg(out.m(), mdl);
rewriter_tpl<rd_over_wr_rewriter> rw(out.m(), false, cfg);
qembp::rd_over_wr_rewriter cfg(out.m(), mdl);
rewriter_tpl<qembp::rd_over_wr_rewriter> rw(out.m(), false, cfg);
rw(in, out);
if (cfg.m_sc.empty()) return;
expr_ref_vector sc(out.m());

3
src/sat/CMakeLists.txt
View file

@ -15,7 +15,7 @@ z3_add_component(sat
sat_config.cpp
sat_cut_simplifier.cpp
sat_cutset.cpp
sat_ddfw.cpp
sat_ddfw_wrapper.cpp
sat_drat.cpp
sat_elim_eqs.cpp
sat_elim_vars.cpp
@ -43,7 +43,6 @@ z3_add_component(sat
params
PYG_FILES
sat_asymm_branch_params.pyg
sat_params.pyg
sat_scc_params.pyg
sat_simplifier_params.pyg
)

2
src/sat/sat_config.cpp
View file

@ -16,9 +16,9 @@ Author:
Revision History:
--*/
#include "params/sat_params.hpp"
#include "sat/sat_config.h"
#include "sat/sat_types.h"
#include "sat/sat_params.hpp"
#include "sat/sat_simplifier_params.hpp"
#include "params/solver_params.hpp"

85
src/sat/sat_ddfw_wrapper.cpp Normal file
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@ -0,0 +1,85 @@
/*++
Copyright (c) 2019 Microsoft Corporation
Module Name:
sat_ddfw_wrapper.cpp
*/
#include "sat/sat_ddfw_wrapper.h"
#include "sat/sat_solver.h"
#include "sat/sat_parallel.h"
namespace sat {
lbool ddfw_wrapper::check(unsigned sz, literal const* assumptions, parallel* p) {
flet<parallel*> _p(m_par, p);
m_ddfw.m_parallel_sync = nullptr;
if (m_par) {
m_ddfw.m_parallel_sync = [&]() -> bool {
if (should_parallel_sync()) {
do_parallel_sync();
return true;
}
else
return false;
};
}
return m_ddfw.check(sz, assumptions);
}
bool ddfw_wrapper::should_parallel_sync() {
return m_par != nullptr && m_ddfw.m_flips >= m_parsync_next;
}
void ddfw_wrapper::do_parallel_sync() {
if (m_par->from_solver(*this))
m_par->to_solver(*this);
++m_parsync_count;
m_parsync_next *= 3;
m_parsync_next /= 2;
}
void ddfw_wrapper::reinit(solver& s, bool_vector const& phase) {
add(s);
m_ddfw.add_assumptions();
for (unsigned v = 0; v < phase.size(); ++v) {
m_ddfw.value(v) = phase[v];
m_ddfw.reward(v) = 0;
m_ddfw.make_count(v) = 0;
}
m_ddfw.init_clause_data();
m_ddfw.flatten_use_list();
}
void ddfw_wrapper::add(solver const& s) {
m_ddfw.set_seed(s.get_config().m_random_seed);
m_ddfw.m_clauses.reset();
m_ddfw.m_use_list.reset();
m_ddfw.m_num_non_binary_clauses = 0;
unsigned trail_sz = s.init_trail_size();
for (unsigned i = 0; i < trail_sz; ++i) {
m_ddfw.add(1, s.m_trail.data() + i);
}
unsigned sz = s.m_watches.size();
for (unsigned l_idx = 0; l_idx < sz; ++l_idx) {
literal l1 = ~to_literal(l_idx);
watch_list const & wlist = s.m_watches[l_idx];
for (watched const& w : wlist) {
if (!w.is_binary_non_learned_clause())
continue;
literal l2 = w.get_literal();
if (l1.index() > l2.index())
continue;
literal ls[2] = { l1, l2 };
m_ddfw.add(2, ls);
}
}
for (clause* c : s.m_clauses)
m_ddfw.add(c->size(), c->begin());
}
}

89
src/sat/sat_ddfw_wrapper.h Normal file
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@ -0,0 +1,89 @@
/*++
Copyright (c) 2019 Microsoft Corporation
Module Name:
sat_ddfw_wrapper.h
--*/
#pragma once
#include "util/uint_set.h"
#include "util/rlimit.h"
#include "util/params.h"
#include "util/ema.h"
#include "util/sat_sls.h"
#include "util/map.h"
#include "ast/sls/sat_ddfw.h"
#include "sat/sat_types.h"
namespace sat {
class solver;
class parallel;
class ddfw_wrapper : public i_local_search {
protected:
ddfw m_ddfw;
parallel* m_par = nullptr;
unsigned m_parsync_count = 0;
uint64_t m_parsync_next = 0;
void do_parallel_sync();
bool should_parallel_sync();
public:
ddfw_wrapper() {}
~ddfw_wrapper() override {}
void set_plugin(local_search_plugin* p) { m_ddfw.set_plugin(p); }
lbool check(unsigned sz, literal const* assumptions, parallel* p) override;
void updt_params(params_ref const& p) override { m_ddfw.updt_params(p); }
model const& get_model() const override { return m_ddfw.get_model(); }
reslimit& rlimit() override { return m_ddfw.rlimit(); }
void set_seed(unsigned n) override { m_ddfw.set_seed(n); }
void add(solver const& s) override;
bool get_value(bool_var v) const override { return m_ddfw.get_value(v); }
std::ostream& display(std::ostream& out) const { return m_ddfw.display(out); }
// for parallel integration
unsigned num_non_binary_clauses() const override { return m_ddfw.num_non_binary_clauses(); }
void reinit(solver& s, bool_vector const& phase) override;
void collect_statistics(statistics& st) const override {}
double get_priority(bool_var v) const override { return m_ddfw.get_priority(v); }
// access clause information and state of Boolean search
indexed_uint_set& unsat_set() { return m_ddfw.unsat_set(); }
vector<clause_info> const& clauses() const { return m_ddfw.clauses(); }
clause_info& get_clause_info(unsigned idx) { return m_ddfw.get_clause_info(idx); }
void remove_assumptions() { m_ddfw.remove_assumptions(); }
void flip(bool_var v) { m_ddfw.flip(v); }
inline double get_reward(bool_var v) const { return m_ddfw.get_reward(v); }
void add(unsigned sz, literal const* c) { m_ddfw.add(sz, c); }
void reinit() { m_ddfw.reinit(); }
};
}

2
src/sat/sat_local_search.cpp
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@ -19,7 +19,7 @@ Notes:
#include "sat/sat_local_search.h"
#include "sat/sat_solver.h"
#include "sat/sat_params.hpp"
#include "params/sat_params.hpp"
#include "util/timer.h"
namespace sat {

9
src/sat/sat_solver.cpp
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@ -29,7 +29,7 @@ Revision History:
#include "sat/sat_solver.h"
#include "sat/sat_integrity_checker.h"
#include "sat/sat_lookahead.h"
#include "sat/sat_ddfw.h"
#include "sat/sat_ddfw_wrapper.h"
#include "sat/sat_prob.h"
#include "sat/sat_anf_simplifier.h"
#include "sat/sat_cut_simplifier.h"
@ -1365,7 +1365,7 @@ namespace sat {
}
literal_vector _lits;
scoped_limits scoped_rl(rlimit());
m_local_search = alloc(ddfw);
m_local_search = alloc(ddfw_wrapper);
scoped_ls _ls(*this);
SASSERT(m_local_search);
m_local_search->add(*this);
@ -1442,7 +1442,7 @@ namespace sat {
lbool solver::do_ddfw_search(unsigned num_lits, literal const* lits) {
if (m_ext) return l_undef;
SASSERT(!m_local_search);
m_local_search = alloc(ddfw);
m_local_search = alloc(ddfw_wrapper);
return invoke_local_search(num_lits, lits);
}
@ -1485,7 +1485,7 @@ namespace sat {
// set up ddfw search
for (int i = 0; i < num_ddfw; ++i) {
ddfw* d = alloc(ddfw);
ddfw_wrapper* d = alloc(ddfw_wrapper);
d->updt_params(m_params);
d->set_seed(m_config.m_random_seed + i);
d->add(*this);
@ -2932,6 +2932,7 @@ namespace sat {
bool_var v = m_trail[i].var();
m_best_phase[v] = m_phase[v];
}
set_has_new_best_phase(true);
}
}

6
src/sat/sat_solver.h
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@ -152,6 +152,7 @@ namespace sat {
bool_vector m_phase;
bool_vector m_best_phase;
bool_vector m_prev_phase;
bool m_new_best_phase = false;
svector<char> m_assigned_since_gc;
search_state m_search_state;
unsigned m_search_unsat_conflicts;
@ -228,7 +229,7 @@ namespace sat {
friend class parallel;
friend class lookahead;
friend class local_search;
friend class ddfw;
friend class ddfw_wrapper;
friend class prob;
friend class unit_walk;
friend struct mk_stat;
@ -380,6 +381,9 @@ namespace sat {
bool was_eliminated(literal l) const { return was_eliminated(l.var()); }
void set_phase(literal l) override { if (l.var() < num_vars()) m_best_phase[l.var()] = m_phase[l.var()] = !l.sign(); }
bool get_phase(bool_var b) { return m_phase.get(b, false); }
bool get_best_phase(bool_var b) { return m_best_phase.get(b, false); }
void set_has_new_best_phase(bool b) { m_new_best_phase = b; }
bool has_new_best_phase() const { return m_new_best_phase; }
void move_to_front(bool_var b);
unsigned scope_lvl() const { return m_scope_lvl; }
unsigned search_lvl() const { return m_search_lvl; }

2
src/sat/sat_solver/inc_sat_solver.cpp
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@ -39,7 +39,7 @@ Notes:
#include "model/model_v2_pp.h"
#include "model/model_evaluator.h"
#include "sat/sat_solver.h"
#include "sat/sat_params.hpp"
#include "params/sat_params.hpp"
#include "sat/smt/euf_solver.h"
#include "sat/tactic/goal2sat.h"
#include "sat/tactic/sat2goal.h"

7
src/sat/sat_solver/sat_smt_solver.cpp
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@ -33,7 +33,7 @@ Notes:
#include "model/model_evaluator.h"
#include "sat/sat_solver.h"
#include "solver/simplifier_solver.h"
#include "sat/sat_params.hpp"
#include "params/sat_params.hpp"
#include "sat/smt/euf_solver.h"
#include "sat/tactic/goal2sat.h"
#include "sat/tactic/sat2goal.h"
@ -586,8 +586,9 @@ private:
void add_assumption(expr* a) {
init_goal2sat();
m_dep.insert(a, m_goal2sat.internalize(a));
get_euf()->add_assertion(a);
auto lit = m_goal2sat.internalize(a);
m_dep.insert(a, lit);
get_euf()->add_clause(1, &lit);
}
void internalize_assumptions(expr_ref_vector const& asms) {

2
src/sat/smt/CMakeLists.txt
View file

@ -3,7 +3,6 @@ z3_add_component(sat_smt
arith_axioms.cpp
arith_diagnostics.cpp
arith_internalize.cpp
arith_sls.cpp
arith_solver.cpp
arith_value.cpp
array_axioms.cpp
@ -22,7 +21,6 @@ z3_add_component(sat_smt
euf_ackerman.cpp
euf_internalize.cpp
euf_invariant.cpp
euf_local_search.cpp
euf_model.cpp
euf_proof.cpp
euf_proof_checker.cpp

1
src/sat/smt/arith_axioms.cpp
View file

@ -547,6 +547,7 @@ namespace arith {
}
void solver::new_diseq_eh(euf::th_eq const& e) {
TRACE("artih", tout << mk_bounded_pp(e.eq(), m) << "\n");
ensure_column(e.v1());
ensure_column(e.v2());
m_delayed_eqs.push_back(std::make_pair(e, false));

642
src/sat/smt/arith_sls.cpp
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@ -1,642 +0,0 @@
/*++
Copyright (c) 2023 Microsoft Corporation
Module Name:
arith_local_search.cpp
Abstract:
Local search dispatch for SMT
Author:
Nikolaj Bjorner (nbjorner) 2023-02-07
--*/
#include "sat/sat_solver.h"
#include "sat/smt/arith_solver.h"
namespace arith {
sls::sls(solver& s):
s(s), m(s.m) {}
void sls::reset() {
m_bool_vars.reset();
m_vars.reset();
m_terms.reset();
}
void sls::save_best_values() {
for (unsigned v = 0; v < s.get_num_vars(); ++v)
m_vars[v].m_best_value = m_vars[v].m_value;
check_ineqs();
if (unsat().size() == 1) {
auto idx = *unsat().begin();
verbose_stream() << idx << "\n";
auto const& c = *m_bool_search->m_clauses[idx].m_clause;
verbose_stream() << c << "\n";
for (auto lit : c) {
bool_var bv = lit.var();
ineq* i = atom(bv);
if (i)
verbose_stream() << lit << ": " << *i << "\n";
}
verbose_stream() << "\n";
}
}
void sls::store_best_values() {
// first compute assignment to terms
// then update non-basic variables in tableau.
if (!unsat().empty())
return;
for (auto const& [t,v] : m_terms) {
int64_t val = 0;
lp::lar_term const& term = s.lp().get_term(t);
for (lp::lar_term::ival const& arg : term) {
auto t2 = arg.j();
auto w = s.lp().local_to_external(t2);
val += to_numeral(arg.coeff()) * m_vars[w].m_best_value;
}
m_vars[v].m_best_value = val;
}
for (unsigned v = 0; v < s.get_num_vars(); ++v) {
if (s.is_bool(v))
continue;
if (!s.lp().external_is_used(v))
continue;
int64_t new_value = m_vars[v].m_best_value;
s.ensure_column(v);
lp::lpvar vj = s.lp().external_to_local(v);
SASSERT(vj != lp::null_lpvar);
if (!s.lp().is_base(vj)) {
rational new_value_(new_value, rational::i64());
lp::impq val(new_value_, rational::zero());
s.lp().set_value_for_nbasic_column(vj, val);
}
}
lbool r = s.make_feasible();
VERIFY (!unsat().empty() || r == l_true);
#if 0
if (unsat().empty())
s.m_num_conflicts = s.get_config().m_arith_propagation_threshold;
#endif
auto check_bool_var = [&](sat::bool_var bv) {
auto* ineq = m_bool_vars.get(bv, nullptr);
if (!ineq)
return;
api_bound* b = nullptr;
s.m_bool_var2bound.find(bv, b);
if (!b)
return;
auto bound = b->get_value();
theory_var v = b->get_var();
if (s.get_phase(bv) == m_bool_search->get_model()[bv])
return;
switch (b->get_bound_kind()) {
case lp_api::lower_t:
verbose_stream() << "v" << v << " " << bound << " <= " << s.get_value(v) << " " << m_vars[v].m_best_value << "\n";
break;
case lp_api::upper_t:
verbose_stream() << "v" << v << " " << bound << " >= " << s.get_value(v) << " " << m_vars[v].m_best_value << "\n";
break;
}
int64_t value = 0;
for (auto const& [coeff, v] : ineq->m_args) {
value += coeff * m_vars[v].m_best_value;
}
ineq->m_args_value = value;
verbose_stream() << *ineq << " dtt " << dtt(false, *ineq) << " phase " << s.get_phase(bv) << " model " << m_bool_search->get_model()[bv] << "\n";
for (auto const& [coeff, v] : ineq->m_args)
verbose_stream() << "v" << v << " := " << m_vars[v].m_best_value << "\n";
s.display(verbose_stream());
display(verbose_stream());
UNREACHABLE();
exit(0);
};
if (unsat().empty()) {
for (bool_var v = 0; v < s.s().num_vars(); ++v)
check_bool_var(v);
}
}
void sls::set(sat::ddfw* d) {
m_bool_search = d;
reset();
m_bool_vars.reserve(s.s().num_vars());
add_vars();
for (unsigned i = 0; i < d->num_clauses(); ++i)
for (sat::literal lit : *d->get_clause_info(i).m_clause)
init_bool_var(lit.var());
for (unsigned v = 0; v < s.s().num_vars(); ++v)
init_bool_var_assignment(v);
d->set(this);
}
// distance to true
int64_t sls::dtt(bool sign, int64_t args, ineq const& ineq) const {
switch (ineq.m_op) {
case ineq_kind::LE:
if (sign) {
if (args <= ineq.m_bound)
return ineq.m_bound - args + 1;
return 0;
}
if (args <= ineq.m_bound)
return 0;
return args - ineq.m_bound;
case ineq_kind::EQ:
if (sign) {
if (args == ineq.m_bound)
return 1;
return 0;
}
if (args == ineq.m_bound)
return 0;
return 1;
case ineq_kind::NE:
if (sign) {
if (args == ineq.m_bound)
return 0;
return 1;
}
if (args == ineq.m_bound)
return 1;
return 0;
case ineq_kind::LT:
if (sign) {
if (args < ineq.m_bound)
return ineq.m_bound - args;
return 0;
}
if (args < ineq.m_bound)
return 0;
return args - ineq.m_bound + 1;
default:
UNREACHABLE();
return 0;
}
}
//
// dtt is high overhead. It walks ineq.m_args
// m_vars[w].m_value can be computed outside and shared among calls
// different data-structures for storing coefficients
//
int64_t sls::dtt(bool sign, ineq const& ineq, var_t v, int64_t new_value) const {
for (auto const& [coeff, w] : ineq.m_args)
if (w == v)
return dtt(sign, ineq.m_args_value + coeff * (new_value - m_vars[v].m_value), ineq);
return 1;
}
int64_t sls::dtt(bool sign, ineq const& ineq, int64_t coeff, int64_t old_value, int64_t new_value) const {
return dtt(sign, ineq.m_args_value + coeff * (new_value - old_value), ineq);
}
bool sls::cm(bool old_sign, ineq const& ineq, var_t v, int64_t& new_value) {
for (auto const& [coeff, w] : ineq.m_args)
if (w == v)
return cm(old_sign, ineq, v, coeff, new_value);
return false;
}
bool sls::cm(bool old_sign, ineq const& ineq, var_t v, int64_t coeff, int64_t& new_value) {
SASSERT(ineq.is_true() != old_sign);
VERIFY(ineq.is_true() != old_sign);
auto bound = ineq.m_bound;
auto argsv = ineq.m_args_value;
bool solved = false;
int64_t delta = argsv - bound;
auto make_eq = [&]() {
SASSERT(delta != 0);
if (delta < 0)
new_value = value(v) + (abs(delta) + abs(coeff) - 1) / coeff;
else
new_value = value(v) - (delta + abs(coeff) - 1) / coeff;
solved = argsv + coeff * (new_value - value(v)) == bound;
if (!solved && abs(coeff) == 1) {
verbose_stream() << "did not solve equality " << ineq << " for " << v << "\n";
verbose_stream() << new_value << " " << value(v) << " delta " << delta << " lhs " << (argsv + coeff * (new_value - value(v))) << " bound " << bound << "\n";
UNREACHABLE();
}
return solved;
};
auto make_diseq = [&]() {
if (delta >= 0)
delta++;
else
delta--;
new_value = value(v) + (abs(delta) + abs(coeff) - 1) / coeff;
VERIFY(argsv + coeff * (new_value - value(v)) != bound);
return true;
};
if (!old_sign) {
switch (ineq.m_op) {
case ineq_kind::LE:
// args <= bound -> args > bound
SASSERT(argsv <= bound);
SASSERT(delta <= 0);
--delta;
new_value = value(v) + (abs(delta) + abs(coeff) - 1) / coeff;
VERIFY(argsv + coeff * (new_value - value(v)) > bound);
return true;
case ineq_kind::LT:
// args < bound -> args >= bound
SASSERT(argsv <= ineq.m_bound);
SASSERT(delta <= 0);
new_value = value(v) + (abs(delta) + abs(coeff) - 1) / coeff;
VERIFY(argsv + coeff * (new_value - value(v)) >= bound);
return true;
case ineq_kind::EQ:
return make_diseq();
case ineq_kind::NE:
return make_eq();
default:
UNREACHABLE();
break;
}
}
else {
switch (ineq.m_op) {
case ineq_kind::LE:
SASSERT(argsv > ineq.m_bound);
SASSERT(delta > 0);
new_value = value(v) - (delta + abs(coeff) - 1) / coeff;
VERIFY(argsv + coeff * (new_value - value(v)) <= bound);
return true;
case ineq_kind::LT:
SASSERT(argsv >= ineq.m_bound);
SASSERT(delta >= 0);
++delta;
new_value = value(v) - (abs(delta) + abs(coeff) - 1) / coeff;
VERIFY(argsv + coeff * (new_value - value(v)) < bound);
return true;
case ineq_kind::NE:
return make_diseq();
case ineq_kind::EQ:
return make_eq();
default:
UNREACHABLE();
break;
}
}
return false;
}
// flip on the first positive score
// it could be changed to flip on maximal positive score
// or flip on maximal non-negative score
// or flip on first non-negative score
bool sls::flip(bool sign, ineq const& ineq) {
int64_t new_value;
auto v = ineq.m_var_to_flip;
if (v == UINT_MAX) {
IF_VERBOSE(1, verbose_stream() << "no var to flip\n");
return false;
}
if (!cm(sign, ineq, v, new_value)) {
verbose_stream() << "no critical move for " << v << "\n";
return false;
}
update(v, new_value);
return true;
}
//
// dscore(op) = sum_c (dts(c,alpha) - dts(c,alpha_after)) * weight(c)
// TODO - use cached dts instead of computed dts
// cached dts has to be updated when the score of literals are updated.
//
double sls::dscore(var_t v, int64_t new_value) const {
double score = 0;
auto const& vi = m_vars[v];
for (auto const& [coeff, bv] : vi.m_bool_vars) {
sat::literal lit(bv, false);
for (auto cl : m_bool_search->get_use_list(lit))
score += (compute_dts(cl) - dts(cl, v, new_value)) * m_bool_search->get_weight(cl);
for (auto cl : m_bool_search->get_use_list(~lit))
score += (compute_dts(cl) - dts(cl, v, new_value)) * m_bool_search->get_weight(cl);
}
return score;
}
//
// cm_score is costly. It involves several cache misses.
// Note that
// - m_bool_search->get_use_list(lit).size() is "often" 1 or 2
// - dtt_old can be saved
//
int sls::cm_score(var_t v, int64_t new_value) {
int score = 0;
auto& vi = m_vars[v];
int64_t old_value = vi.m_value;
for (auto const& [coeff, bv] : vi.m_bool_vars) {
auto const& ineq = *atom(bv);
bool old_sign = sign(bv);
int64_t dtt_old = dtt(old_sign, ineq);
int64_t dtt_new = dtt(old_sign, ineq, coeff, old_value, new_value);
if ((dtt_old == 0) == (dtt_new == 0))
continue;
sat::literal lit(bv, old_sign);
if (dtt_old == 0)
// flip from true to false
lit.neg();
// lit flips form false to true:
for (auto cl : m_bool_search->get_use_list(lit)) {
auto const& clause = get_clause_info(cl);
if (!clause.is_true())
++score;
}
// ignore the situation where clause contains multiple literals using v
for (auto cl : m_bool_search->get_use_list(~lit)) {
auto const& clause = get_clause_info(cl);
if (clause.m_num_trues == 1)
--score;
}
}
return score;
}
int64_t sls::compute_dts(unsigned cl) const {
int64_t d(1), d2;
bool first = true;
for (auto a : get_clause(cl)) {
auto const* ineq = atom(a.var());
if (!ineq)
continue;
d2 = dtt(a.sign(), *ineq);
if (first)
d = d2, first = false;
else
d = std::min(d, d2);
if (d == 0)
break;
}
return d;
}
int64_t sls::dts(unsigned cl, var_t v, int64_t new_value) const {
int64_t d(1), d2;
bool first = true;
for (auto lit : get_clause(cl)) {
auto const* ineq = atom(lit.var());
if (!ineq)
continue;
d2 = dtt(lit.sign(), *ineq, v, new_value);
if (first)
d = d2, first = false;
else
d = std::min(d, d2);
if (d == 0)
break;
}
return d;
}
void sls::update(var_t v, int64_t new_value) {
auto& vi = m_vars[v];
auto old_value = vi.m_value;
for (auto const& [coeff, bv] : vi.m_bool_vars) {
auto& ineq = *atom(bv);
bool old_sign = sign(bv);
sat::literal lit(bv, old_sign);
SASSERT(is_true(lit));
ineq.m_args_value += coeff * (new_value - old_value);
int64_t dtt_new = dtt(old_sign, ineq);
if (dtt_new != 0)
m_bool_search->flip(bv);
SASSERT(dtt(sign(bv), ineq) == 0);
}
vi.m_value = new_value;
}
void sls::add_vars() {
SASSERT(m_vars.empty());
for (unsigned v = 0; v < s.get_num_vars(); ++v) {
int64_t value = s.is_registered_var(v) ? to_numeral(s.get_ivalue(v).x) : 0;
auto k = s.is_int(v) ? sls::var_kind::INT : sls::var_kind::REAL;
m_vars.push_back({ value, value, k, {} });
}
}
sls::ineq& sls::new_ineq(ineq_kind op, int64_t const& bound) {
auto* i = alloc(ineq);
i->m_bound = bound;
i->m_op = op;
return *i;
}
void sls::add_arg(sat::bool_var bv, ineq& ineq, int64_t const& c, var_t v) {
ineq.m_args.push_back({ c, v });
ineq.m_args_value += c * value(v);
m_vars[v].m_bool_vars.push_back({ c, bv});
}
int64_t sls::to_numeral(rational const& r) {
if (r.is_int64())
return r.get_int64();
return 0;
}
void sls::add_args(sat::bool_var bv, ineq& ineq, lp::lpvar t, theory_var v, int64_t sign) {
if (s.lp().column_has_term(t)) {
lp::lar_term const& term = s.lp().get_term(t);
m_terms.push_back({t,v});
for (lp::lar_term::ival arg : term) {
auto t2 = arg.j();
auto w = s.lp().local_to_external(t2);
add_arg(bv, ineq, sign * to_numeral(arg.coeff()), w);
}
}
else
add_arg(bv, ineq, sign, s.lp().local_to_external(t));
}
void sls::init_bool_var(sat::bool_var bv) {
if (m_bool_vars.get(bv, nullptr))
return;
api_bound* b = nullptr;
s.m_bool_var2bound.find(bv, b);
if (b) {
auto t = b->column_index();
rational bound = b->get_value();
bool should_minus = false;
sls::ineq_kind op;
should_minus = b->get_bound_kind() == lp_api::bound_kind::lower_t;
op = sls::ineq_kind::LE;
if (should_minus)
bound.neg();
auto& ineq = new_ineq(op, to_numeral(bound));
add_args(bv, ineq, t, b->get_var(), should_minus ? -1 : 1);
m_bool_vars.set(bv, &ineq);
m_bool_search->set_external(bv);
return;
}
expr* e = s.bool_var2expr(bv);
expr* l = nullptr, * r = nullptr;
if (e && m.is_eq(e, l, r) && s.a.is_int_real(l)) {
theory_var u = s.get_th_var(l);
theory_var v = s.get_th_var(r);
lp::lpvar tu = s.get_column(u);
lp::lpvar tv = s.get_column(v);
auto& ineq = new_ineq(sls::ineq_kind::EQ, 0);
add_args(bv, ineq, tu, u, 1);
add_args(bv, ineq, tv, v, -1);
m_bool_vars.set(bv, &ineq);
m_bool_search->set_external(bv);
return;
}
}
void sls::init_bool_var_assignment(sat::bool_var v) {
auto* ineq = m_bool_vars.get(v, nullptr);
if (ineq && is_true(sat::literal(v, false)) != (dtt(false, *ineq) == 0))
m_bool_search->flip(v);
}
void sls::init_search() {
on_restart();
}
void sls::finish_search() {
store_best_values();
}
void sls::flip(sat::bool_var v) {
sat::literal lit(v, !sign(v));
SASSERT(!is_true(lit));
auto const* ineq = atom(v);
if (!ineq)
IF_VERBOSE(0, verbose_stream() << "no inequality for variable " << v << "\n");
if (!ineq)
return;
SASSERT(ineq->is_true() == lit.sign());
flip(sign(v), *ineq);
}
double sls::reward(sat::bool_var v) {
if (m_dscore_mode)
return dscore_reward(v);
else
return dtt_reward(v);
}
double sls::dtt_reward(sat::bool_var bv0) {
bool sign0 = sign(bv0);
auto* ineq = atom(bv0);
if (!ineq)
return -1;
int64_t new_value;
double max_result = -1;
for (auto const & [coeff, x] : ineq->m_args) {
if (!cm(sign0, *ineq, x, coeff, new_value))
continue;
double result = 0;
auto old_value = m_vars[x].m_value;
for (auto const& [coeff, bv] : m_vars[x].m_bool_vars) {
result += m_bool_search->reward(bv);
continue;
bool old_sign = sign(bv);
auto dtt_old = dtt(old_sign, *atom(bv));
auto dtt_new = dtt(old_sign, *atom(bv), coeff, old_value, new_value);
if ((dtt_new == 0) != (dtt_old == 0))
result += m_bool_search->reward(bv);
}
if (result > max_result) {
max_result = result;
ineq->m_var_to_flip = x;
}
}
return max_result;
}
double sls::dscore_reward(sat::bool_var bv) {
m_dscore_mode = false;
bool old_sign = sign(bv);
sat::literal litv(bv, old_sign);
auto* ineq = atom(bv);
if (!ineq)
return 0;
SASSERT(ineq->is_true() != old_sign);
int64_t new_value;
for (auto const& [coeff, v] : ineq->m_args) {
double result = 0;
if (cm(old_sign, *ineq, v, coeff, new_value))
result = dscore(v, new_value);
// just pick first positive, or pick a max?
if (result > 0) {
ineq->m_var_to_flip = v;
return result;
}
}
return 0;
}
// switch to dscore mode
void sls::on_rescale() {
m_dscore_mode = true;
}
void sls::on_save_model() {
save_best_values();
}
void sls::on_restart() {
for (unsigned v = 0; v < s.s().num_vars(); ++v)
init_bool_var_assignment(v);
check_ineqs();
}
void sls::check_ineqs() {
auto check_bool_var = [&](sat::bool_var bv) {
auto const* ineq = atom(bv);
if (!ineq)
return;
int64_t d = dtt(sign(bv), *ineq);
sat::literal lit(bv, sign(bv));
if (is_true(lit) != (d == 0)) {
verbose_stream() << "invalid assignment " << bv << " " << *ineq << "\n";
}
VERIFY(is_true(lit) == (d == 0));
};
for (unsigned v = 0; v < s.get_num_vars(); ++v)
check_bool_var(v);
}
std::ostream& sls::display(std::ostream& out) const {
for (bool_var bv = 0; bv < s.s().num_vars(); ++bv) {
auto const* ineq = atom(bv);
if (!ineq)
continue;
out << bv << " " << *ineq << "\n";
}
for (unsigned v = 0; v < s.get_num_vars(); ++v) {
if (s.is_bool(v))
continue;
out << "v" << v << " := " << m_vars[v].m_value << " " << m_vars[v].m_best_value << "\n";
}
return out;
}
}

169
src/sat/smt/arith_sls.h
View file

@ -1,169 +0,0 @@
/*++
Copyright (c) 2020 Microsoft Corporation
Module Name:
arith_local_search.h
Abstract:
Theory plugin for arithmetic local search
Author:
Nikolaj Bjorner (nbjorner) 2020-09-08
--*/
#pragma once
#include "util/obj_pair_set.h"
#include "ast/ast_trail.h"
#include "ast/arith_decl_plugin.h"
#include "math/lp/indexed_value.h"
#include "math/lp/lar_solver.h"
#include "math/lp/nla_solver.h"
#include "math/lp/lp_types.h"
#include "math/lp/lp_api.h"
#include "math/polynomial/algebraic_numbers.h"
#include "math/polynomial/polynomial.h"
#include "sat/smt/sat_th.h"
#include "sat/sat_ddfw.h"
namespace arith {
class solver;
// local search portion for arithmetic
class sls : public sat::local_search_plugin {
enum class ineq_kind { EQ, LE, LT, NE };
enum class var_kind { INT, REAL };
typedef unsigned var_t;
typedef unsigned atom_t;
struct config {
double cb = 0.0;
unsigned L = 20;
unsigned t = 45;
unsigned max_no_improve = 500000;
double sp = 0.0003;
};
struct stats {
unsigned m_num_flips = 0;
};
public:
// encode args <= bound, args = bound, args < bound
struct ineq {
vector<std::pair<int64_t, var_t>> m_args;
ineq_kind m_op = ineq_kind::LE;
int64_t m_bound;
int64_t m_args_value;
unsigned m_var_to_flip = UINT_MAX;
bool is_true() const {
switch (m_op) {
case ineq_kind::LE:
return m_args_value <= m_bound;
case ineq_kind::EQ:
return m_args_value == m_bound;
case ineq_kind::NE:
return m_args_value != m_bound;
default:
return m_args_value < m_bound;
}
}
std::ostream& display(std::ostream& out) const {
bool first = true;
for (auto const& [c, v] : m_args)
out << (first ? "" : " + ") << c << " * v" << v, first = false;
switch (m_op) {
case ineq_kind::LE:
return out << " <= " << m_bound << "(" << m_args_value << ")";
case ineq_kind::EQ:
return out << " == " << m_bound << "(" << m_args_value << ")";
case ineq_kind::NE:
return out << " != " << m_bound << "(" << m_args_value << ")";
default:
return out << " < " << m_bound << "(" << m_args_value << ")";
}
}
};
private:
struct var_info {
int64_t m_value;
int64_t m_best_value;
var_kind m_kind = var_kind::INT;
svector<std::pair<int64_t, sat::bool_var>> m_bool_vars;
};
solver& s;
ast_manager& m;
sat::ddfw* m_bool_search = nullptr;
stats m_stats;
config m_config;
scoped_ptr_vector<ineq> m_bool_vars;
vector<var_info> m_vars;
svector<std::pair<lp::lpvar, euf::theory_var>> m_terms;
bool m_dscore_mode = false;
indexed_uint_set& unsat() { return m_bool_search->unsat_set(); }
unsigned num_clauses() const { return m_bool_search->num_clauses(); }
sat::clause& get_clause(unsigned idx) { return *get_clause_info(idx).m_clause; }
sat::clause const& get_clause(unsigned idx) const { return *get_clause_info(idx).m_clause; }
sat::ddfw::clause_info& get_clause_info(unsigned idx) { return m_bool_search->get_clause_info(idx); }
sat::ddfw::clause_info const& get_clause_info(unsigned idx) const { return m_bool_search->get_clause_info(idx); }
bool is_true(sat::literal lit) { return lit.sign() != m_bool_search->get_value(lit.var()); }
bool sign(sat::bool_var v) const { return !m_bool_search->get_value(v); }
void reset();
ineq* atom(sat::bool_var bv) const { return m_bool_vars[bv]; }
bool flip(bool sign, ineq const& ineq);
int64_t dtt(bool sign, ineq const& ineq) const { return dtt(sign, ineq.m_args_value, ineq); }
int64_t dtt(bool sign, int64_t args_value, ineq const& ineq) const;
int64_t dtt(bool sign, ineq const& ineq, var_t v, int64_t new_value) const;
int64_t dtt(bool sign, ineq const& ineq, int64_t coeff, int64_t old_value, int64_t new_value) const;
int64_t dts(unsigned cl, var_t v, int64_t new_value) const;
int64_t compute_dts(unsigned cl) const;
bool cm(bool sign, ineq const& ineq, var_t v, int64_t& new_value);
bool cm(bool sign, ineq const& ineq, var_t v, int64_t coeff, int64_t& new_value);
int cm_score(var_t v, int64_t new_value);
void update(var_t v, int64_t new_value);
double dscore_reward(sat::bool_var v);
double dtt_reward(sat::bool_var v);
double dscore(var_t v, int64_t new_value) const;
void save_best_values();
void store_best_values();
void add_vars();
sls::ineq& new_ineq(ineq_kind op, int64_t const& bound);
void add_arg(sat::bool_var bv, ineq& ineq, int64_t const& c, var_t v);
void add_args(sat::bool_var bv, ineq& ineq, lp::lpvar j, euf::theory_var v, int64_t sign);
void init_bool_var(sat::bool_var v);
void init_bool_var_assignment(sat::bool_var v);
int64_t value(var_t v) const { return m_vars[v].m_value; }
int64_t to_numeral(rational const& r);
void check_ineqs();
std::ostream& display(std::ostream& out) const;
public:
sls(solver& s);
void set(sat::ddfw* d);
void init_search() override;
void finish_search() override;
void flip(sat::bool_var v) override;
double reward(sat::bool_var v) override;
void on_rescale() override;
void on_save_model() override;
void on_restart() override;
};
inline std::ostream& operator<<(std::ostream& out, sls::ineq const& ineq) {
return ineq.display(out);
}
}

29
src/sat/smt/arith_solver.cpp
View file

@ -24,7 +24,6 @@ namespace arith {
solver::solver(euf::solver& ctx, theory_id id) :
th_euf_solver(ctx, symbol("arith"), id),
m_model_eqs(DEFAULT_HASHTABLE_INITIAL_CAPACITY, var_value_hash(*this), var_value_eq(*this)),
m_local_search(*this),
m_resource_limit(*this),
m_bp(*this, m_implied_bounds),
a(m),
@ -988,10 +987,10 @@ namespace arith {
}
bool solver::use_nra_model() {
return m_nla && m_nla->use_nra_model();
return m_nla && m_use_nra_model && m_nla->use_nra_model();
}
bool solver::is_eq(theory_var v1, theory_var v2) {
bool solver::is_eq(theory_var v1, theory_var v2) {
if (use_nra_model()) {
return m_nla->am().eq(nl_value(v1, m_nla->tmp1()), nl_value(v2, m_nla->tmp2()));
}
@ -1006,6 +1005,8 @@ namespace arith {
IF_VERBOSE(12, verbose_stream() << "final-check " << lp().get_status() << "\n");
SASSERT(lp().ax_is_correct());
m_use_nra_model = false;
if (!lp().is_feasible() || lp().has_changed_columns()) {
switch (make_feasible()) {
case l_false:
@ -1038,8 +1039,12 @@ namespace arith {
break;
}
if (!check_delayed_eqs())
return sat::check_result::CR_CONTINUE;
switch (check_nla()) {
case l_true:
m_use_nra_model = true;
break;
case l_false:
return sat::check_result::CR_CONTINUE;
@ -1053,7 +1058,8 @@ namespace arith {
++m_stats.m_assume_eqs;
return sat::check_result::CR_CONTINUE;
}
if (!check_delayed_eqs())
if (!check_delayed_eqs())
return sat::check_result::CR_CONTINUE;
if (!int_undef && !check_bv_terms())
@ -1141,6 +1147,7 @@ namespace arith {
new_eq_eh(e);
else if (is_eq(e.v1(), e.v2())) {
mk_diseq_axiom(e.v1(), e.v2());
TRACE("arith", tout << mk_bounded_pp(e.eq(), m) << " " << use_nra_model() << "\n");
found_diseq = true;
break;
}
@ -1249,9 +1256,9 @@ namespace arith {
for (auto ev : m_explanation)
set_evidence(ev.ci());
TRACE("arith",
TRACE("arith_conflict",
tout << "Lemma - " << (is_conflict ? "conflict" : "propagation") << "\n";
for (literal c : m_core) tout << c << ": " << literal2expr(c) << "\n";
for (literal c : m_core) tout << c << ": " << literal2expr(c) << " := " << s().value(c) << "\n";
for (auto p : m_eqs) tout << ctx.bpp(p.first) << " == " << ctx.bpp(p.second) << "\n";);
if (ctx.get_config().m_arith_validate)
@ -1271,6 +1278,10 @@ namespace arith {
m_core.push_back(ctx.mk_literal(m.mk_eq(eq.first->get_expr(), eq.second->get_expr())));
for (literal& c : m_core)
c.neg();
// it is possible if multiple lemmas are added at the same time.
if (any_of(m_core, [&](literal c) { return s().value(c) == l_true; }))
return;
add_redundant(m_core, explain(ty));
}
@ -1508,6 +1519,7 @@ namespace arith {
case l_undef:
break;
}
TRACE("arith", tout << "nla " << r << "\n");
return r;
}
@ -1521,10 +1533,13 @@ namespace arith {
}
for (auto const& ineq : m_nla->literals()) {
auto lit = mk_ineq_literal(ineq);
if (s().value(lit) == l_true)
continue;
ctx.mark_relevant(lit);
s().set_phase(lit);
// verbose_stream() << lit << ":= " << s().value(lit) << "\n";
// force trichotomy axiom for equality literals
if (ineq.cmp() == lp::EQ) {
if (ineq.cmp() == lp::EQ && false) {
nla::lemma l;
l.push_back(ineq);
l.push_back(nla::ineq(lp::LT, ineq.term(), ineq.rs()));

7
src/sat/smt/arith_solver.h
View file

@ -28,8 +28,6 @@ Author:
#include "math/polynomial/algebraic_numbers.h"
#include "math/polynomial/polynomial.h"
#include "sat/smt/sat_th.h"
#include "sat/smt/arith_sls.h"
#include "sat/sat_ddfw.h"
namespace euf {
class solver;
@ -186,8 +184,6 @@ namespace arith {
coeffs().pop_back();
}
};
sls m_local_search;
typedef vector<std::pair<rational, lpvar>> var_coeffs;
vector<rational> m_columns;
@ -234,6 +230,7 @@ namespace arith {
// non-linear arithmetic
scoped_ptr<nla::solver> m_nla;
bool m_use_nra_model = false;
// integer arithmetic
scoped_ptr<lp::int_solver> m_lia;
@ -513,8 +510,6 @@ namespace arith {
bool enable_ackerman_axioms(euf::enode* n) const override { return !a.is_add(n->get_expr()); }
bool has_unhandled() const override { return m_not_handled != nullptr; }
void set_bool_search(sat::ddfw* ddfw) override { m_local_search.set(ddfw); }
// bounds and equality propagation callbacks
lp::lar_solver& lp() { return *m_solver; }
lp::lar_solver const& lp() const { return *m_solver; }

4
src/sat/smt/bv_ackerman.cpp
View file

@ -118,8 +118,8 @@ namespace bv {
}
}
if (glue < max_glue)
v.m_glue = (sz > 6 && 2*glue <= sz) ? 0 : glue;
if (glue < max_glue)
v.m_glue = glue; // (sz > 6 && 2 * glue <= sz) ? 0 : glue;
}
void ackerman::remove(vv* p) {

6
src/sat/smt/euf_internalize.cpp
View file

@ -525,8 +525,8 @@ namespace euf {
return n;
}
void solver::add_assertion(expr* f) {
m_assertions.push_back(f);
m_trail.push(push_back_vector(m_assertions));
void solver::add_clause(unsigned n, sat::literal const* lits) {
m_top_level_clauses.push_back(sat::literal_vector(n, lits));
m_trail.push(push_back_vector(m_top_level_clauses));
}
}

50
src/sat/smt/euf_local_search.cpp
View file

@ -1,50 +0,0 @@
/*++
Copyright (c) 2020 Microsoft Corporation
Module Name:
euf_local_search.cpp
Abstract:
Local search dispatch for SMT
Author:
Nikolaj Bjorner (nbjorner) 2023-02-07
--*/
#include "sat/sat_solver.h"
#include "sat/sat_ddfw.h"
#include "sat/smt/euf_solver.h"
namespace euf {
lbool solver::local_search(bool_vector& phase) {
scoped_limits scoped_rl(m.limit());
sat::ddfw bool_search;
bool_search.reinit(s(), phase);
bool_search.updt_params(s().params());
bool_search.set_seed(rand());
scoped_rl.push_child(&(bool_search.rlimit()));
for (auto* th : m_solvers)
th->set_bool_search(&bool_search);
bool_search.check(0, nullptr, nullptr);
auto const& mdl = bool_search.get_model();
for (unsigned i = 0; i < mdl.size(); ++i)
phase[i] = mdl[i] == l_true;
if (bool_search.unsat_set().empty()) {
enable_trace("arith");
enable_trace("sat");
enable_trace("euf");
TRACE("sat", s().display(tout));
}
return bool_search.unsat_set().empty() ? l_true : l_undef;
}
}

2
src/sat/smt/euf_proof_checker.cpp
View file

@ -21,7 +21,7 @@ Author:
#include "ast/ast_ll_pp.h"
#include "ast/arith_decl_plugin.h"
#include "smt/smt_solver.h"
#include "sat/sat_params.hpp"
#include "params/sat_params.hpp"
#include "sat/smt/euf_proof_checker.h"
#include "sat/smt/arith_theory_checker.h"
#include "sat/smt/q_theory_checker.h"

1
src/sat/smt/euf_solver.cpp
View file

@ -55,7 +55,6 @@ namespace euf {
m_smt_proof_checker(m, p),
m_clause(m),
m_expr_args(m),
m_assertions(m),
m_values(m)
{
updt_params(p);

19
src/sat/smt/euf_solver.h
View file

@ -100,15 +100,6 @@ namespace euf {
scope(unsigned l) : m_var_lim(l) {}
};
struct local_search_config {
double cb = 0.0;
unsigned L = 20;
unsigned t = 45;
unsigned max_no_improve = 500000;
double sp = 0.0003;
};
size_t* to_ptr(sat::literal l) { return TAG(size_t*, reinterpret_cast<size_t*>((size_t)(l.index() << 4)), 1); }
size_t* to_ptr(size_t jst) { return TAG(size_t*, reinterpret_cast<size_t*>(jst), 2); }
bool is_literal(size_t* p) const { return GET_TAG(p) == 1; }
@ -127,7 +118,6 @@ namespace euf {
sat::sat_internalizer& si;
relevancy m_relevancy;
smt_params m_config;
local_search_config m_ls_config;
euf::egraph m_egraph;
trail_stack m_trail;
stats m_stats;
@ -174,7 +164,7 @@ namespace euf {
symbol m_smt = symbol("smt");
expr_ref_vector m_clause;
expr_ref_vector m_expr_args;
expr_ref_vector m_assertions;
vector<sat::literal_vector> m_top_level_clauses;
// internalization
@ -356,7 +346,6 @@ namespace euf {
void add_assumptions(sat::literal_set& assumptions) override;
bool tracking_assumptions() override;
std::string reason_unknown() override { return m_reason_unknown; }
lbool local_search(bool_vector& phase) override;
void propagate(literal lit, ext_justification_idx idx);
bool propagate(enode* a, enode* b, ext_justification_idx idx);
@ -485,8 +474,10 @@ namespace euf {
bool enable_ackerman_axioms(expr* n) const;
bool is_fixed(euf::enode* n, expr_ref& val, sat::literal_vector& explain);
void add_assertion(expr* f);
expr_ref_vector const& get_assertions() { return m_assertions; }
// void add_assertion(expr* f);
// expr_ref_vector const& get_assertions() { return m_assertions; }
void add_clause(unsigned n, sat::literal const* lits);
vector <sat::literal_vector> const& top_level_clauses() const { return m_top_level_clauses; }
model_ref get_sls_model();
// relevancy

708
src/sat/smt/intblast_solver.cpp
View file

@ -22,6 +22,10 @@ Author:
namespace intblast {
void translator_trail::push(push_back_vector<expr_ref_vector> const& c) { ctx.push(c); }
void translator_trail::push(push_back_vector<ptr_vector<app>> const& c) { ctx.push(c); }
void translator_trail::push_idx(set_vector_idx_trail<expr_ref_vector> const& c) { ctx.push(c); }
solver::solver(euf::solver& ctx) :
th_euf_solver(ctx, symbol("intblast"), ctx.get_manager().get_family_id("bv")),
ctx(ctx),
@ -29,9 +33,8 @@ namespace intblast {
m(ctx.get_manager()),
bv(m),
a(m),
m_translate(m),
m_args(m),
m_pinned(m)
trail(ctx),
m_translator(m, trail)
{}
euf::theory_var solver::mk_var(euf::enode* n) {
@ -85,49 +88,22 @@ namespace intblast {
SASSERT(!n->is_attached_to(get_id()));
mk_var(n);
SASSERT(n->is_attached_to(get_id()));
internalize_bv(a);
m_translator.internalize_bv(a);
return true;
}
void solver::eq_internalized(euf::enode* n) {
expr* e = n->get_expr();
expr* x = nullptr, * y = nullptr;
VERIFY(m.is_eq(n->get_expr(), x, y));
SASSERT(bv.is_bv(x));
if (!is_translated(e)) {
ensure_translated(x);
ensure_translated(y);
m_args.reset();
m_args.push_back(a.mk_sub(translated(x), translated(y)));
set_translated(e, m.mk_eq(umod(x, 0), a.mk_int(0)));
}
m_preds.push_back(e);
TRACE("bv", tout << mk_pp(e, m) << " " << mk_pp(translated(e), m) << "\n");
ctx.push(push_back_vector(m_preds));
}
void solver::set_translated(expr* e, expr* r) {
SASSERT(r);
SASSERT(!is_translated(e));
m_translate.setx(e->get_id(), r);
ctx.push(set_vector_idx_trail(m_translate, e->get_id()));
}
void solver::internalize_bv(app* e) {
ensure_translated(e);
if (m.is_bool(e)) {
m_preds.push_back(e);
ctx.push(push_back_vector(m_preds));
}
m_translator.translate_eq(n->get_expr());
}
bool solver::add_bound_axioms() {
if (m_vars_qhead == m_vars.size())
auto const& vars = m_translator.vars();
if (m_vars_qhead == vars.size())
return false;
ctx.push(value_trail(m_vars_qhead));
for (; m_vars_qhead < m_vars.size(); ++m_vars_qhead) {
auto v = m_vars[m_vars_qhead];
auto w = translated(v);
for (; m_vars_qhead < vars.size(); ++m_vars_qhead) {
auto v = vars[m_vars_qhead];
auto w = m_translator.translated(v);
auto sz = rational::power_of_two(bv.get_bv_size(v->get_sort()));
auto lo = ctx.mk_literal(a.mk_ge(w, a.mk_int(0)));
auto hi = ctx.mk_literal(a.mk_le(w, a.mk_int(sz - 1)));
@ -140,12 +116,13 @@ namespace intblast {
}
bool solver::add_predicate_axioms() {
if (m_preds_qhead == m_preds.size())
auto const& preds = m_translator.preds();
if (m_preds_qhead == preds.size())
return false;
ctx.push(value_trail(m_preds_qhead));
for (; m_preds_qhead < m_preds.size(); ++m_preds_qhead) {
expr* e = m_preds[m_preds_qhead];
expr_ref r(translated(e), m);
for (; m_preds_qhead < preds.size(); ++m_preds_qhead) {
expr* e = preds[m_preds_qhead];
expr_ref r(m_translator.translated(e), m);
ctx.get_rewriter()(r);
auto a = expr2literal(e);
auto b = mk_literal(r);
@ -158,31 +135,7 @@ namespace intblast {
bool solver::unit_propagate() {
return add_bound_axioms() || add_predicate_axioms();
}
void solver::ensure_translated(expr* e) {
if (m_translate.get(e->get_id(), nullptr))
return;
ptr_vector<expr> todo;
ast_fast_mark1 visited;
todo.push_back(e);
visited.mark(e);
for (unsigned i = 0; i < todo.size(); ++i) {
expr* e = todo[i];
if (!is_app(e))
continue;
app* a = to_app(e);
if (m.is_bool(e) && a->get_family_id() != bv.get_family_id())
continue;
for (auto arg : *a)
if (!visited.is_marked(arg) && !m_translate.get(arg->get_id(), nullptr)) {
visited.mark(arg);
todo.push_back(arg);
}
}
std::stable_sort(todo.begin(), todo.end(), [&](expr* a, expr* b) { return get_depth(a) < get_depth(b); });
for (expr* e : todo)
translate_expr(e);
}
}
lbool solver::check_axiom(sat::literal_vector const& lits) {
sat::literal_vector core;
@ -198,14 +151,10 @@ namespace intblast {
}
lbool solver::check_core(sat::literal_vector const& lits, euf::enode_pair_vector const& eqs) {
m_core.reset();
m_vars.reset();
m_is_plugin = false;
m_translator.reset(false);
m_solver = mk_smt2_solver(m, s.params(), symbol::null);
for (unsigned i = 0; i < m_translate.size(); ++i)
m_translate[i] = nullptr;
expr_ref_vector es(m), original_es(m);
for (auto lit : lits)
es.push_back(ctx.literal2expr(lit));
@ -222,8 +171,8 @@ namespace intblast {
translate(es);
for (auto e : m_vars) {
auto v = translated(e);
for (auto e : m_translator.vars()) {
auto v = m_translator.translated(e);
auto b = rational::power_of_two(bv.get_bv_size(e));
m_solver->assert_expr(a.mk_le(a.mk_int(0), v));
m_solver->assert_expr(a.mk_lt(v, a.mk_int(b)));
@ -331,8 +280,8 @@ namespace intblast {
translate(es);
for (auto e : m_vars) {
auto v = translated(e);
for (auto e : m_translator.vars()) {
auto v = m_translator.translated(e);
auto b = rational::power_of_two(bv.get_bv_size(e));
m_solver->assert_expr(a.mk_le(a.mk_int(0), v));
m_solver->assert_expr(a.mk_lt(v, a.mk_int(b)));
@ -377,7 +326,7 @@ namespace intblast {
void solver::sorted_subterms(expr_ref_vector& es, ptr_vector<expr>& sorted) {
expr_fast_mark1 visited;
for (expr* e : es) {
if (is_translated(e))
if (m_translator.is_translated(e))
continue;
if (visited.is_marked(e))
continue;
@ -389,7 +338,7 @@ namespace intblast {
if (is_app(e)) {
app* a = to_app(e);
for (expr* arg : *a) {
if (!visited.is_marked(arg) && !is_translated(arg)) {
if (!visited.is_marked(arg) && !m_translator.is_translated(arg)) {
visited.mark(arg);
sorted.push_back(arg);
}
@ -399,7 +348,7 @@ namespace intblast {
else if (is_quantifier(e)) {
quantifier* q = to_quantifier(e);
expr* b = q->get_expr();
if (!visited.is_marked(b) && !is_translated(b)) {
if (!visited.is_marked(b) && !m_translator.is_translated(b)) {
visited.mark(b);
sorted.push_back(b);
}
@ -414,20 +363,20 @@ namespace intblast {
sorted_subterms(es, todo);
for (expr* e : todo)
translate_expr(e);
m_translator.translate_expr(e);
TRACE("bv",
for (expr* e : es)
tout << mk_pp(e, m) << "\n->\n" << mk_pp(translated(e), m) << "\n";
tout << mk_pp(e, m) << "\n->\n" << mk_pp(m_translator.translated(e), m) << "\n";
);
for (unsigned i = 0; i < es.size(); ++i)
es[i] = translated(es.get(i));
es[i] = m_translator.translated(es.get(i));
}
sat::check_result solver::check() {
// ensure that bv2int is injective
for (auto e : m_bv2int) {
for (auto e : m_translator.bv2int()) {
euf::enode* n = expr2enode(e);
euf::enode* r1 = n->get_arg(0)->get_root();
for (auto sib : euf::enode_class(n)) {
@ -449,7 +398,7 @@ namespace intblast {
}
// ensure that int2bv respects values
// bv2int(int2bv(x)) = x mod N
for (auto e : m_int2bv) {
for (auto e : m_translator.int2bv()) {
auto n = expr2enode(e);
auto x = n->get_arg(0)->get_expr();
auto bv2int = bv.mk_bv2int(e);
@ -469,595 +418,12 @@ namespace intblast {
return sat::check_result::CR_DONE;
}
bool solver::is_bounded(expr* x, rational const& N) {
return any_of(m_vars, [&](expr* v) {
return is_translated(v) && translated(v) == x && bv_size(v) <= N;
});
}
bool solver::is_non_negative(expr* bv_expr, expr* e) {
auto N = rational::power_of_two(bv.get_bv_size(bv_expr));
rational r;
if (a.is_numeral(e, r))
return r >= 0;
if (is_bounded(e, N))
return true;
expr* x = nullptr, * y = nullptr;
if (a.is_mul(e, x, y))
return is_non_negative(bv_expr, x) && is_non_negative(bv_expr, y);
if (a.is_add(e, x, y))
return is_non_negative(bv_expr, x) && is_non_negative(bv_expr, y);
return false;
}
expr* solver::umod(expr* bv_expr, unsigned i) {
expr* x = arg(i);
rational N = bv_size(bv_expr);
return amod(bv_expr, x, N);
}
expr* solver::smod(expr* bv_expr, unsigned i) {
expr* x = arg(i);
auto N = bv_size(bv_expr);
auto shift = N / 2;
rational r;
if (a.is_numeral(x, r))
return a.mk_int(mod(r + shift, N));
return amod(bv_expr, add(x, a.mk_int(shift)), N);
}
expr_ref solver::mul(expr* x, expr* y) {
expr_ref _x(x, m), _y(y, m);
if (a.is_zero(x))
return _x;
if (a.is_zero(y))
return _y;
if (a.is_one(x))
return _y;
if (a.is_one(y))
return _x;
rational v1, v2;
if (a.is_numeral(x, v1) && a.is_numeral(y, v2))
return expr_ref(a.mk_int(v1 * v2), m);
_x = a.mk_mul(x, y);
return _x;
}
expr_ref solver::add(expr* x, expr* y) {
expr_ref _x(x, m), _y(y, m);
if (a.is_zero(x))
return _y;
if (a.is_zero(y))
return _x;
rational v1, v2;
if (a.is_numeral(x, v1) && a.is_numeral(y, v2))
return expr_ref(a.mk_int(v1 + v2), m);
_x = a.mk_add(x, y);
return _x;
}
/*
* Perform simplifications that are claimed sound when the bit-vector interpretations of
* mod/div always guard the mod and dividend to be non-zero.
* Potentially shady area is for arithmetic expressions created by int2bv.
* They will be guarded by a modulus which does not disappear.
*/
expr* solver::amod(expr* bv_expr, expr* x, rational const& N) {
rational v;
expr* r = nullptr, *c = nullptr, * t = nullptr, * e = nullptr;
if (m.is_ite(x, c, t, e))
r = m.mk_ite(c, amod(bv_expr, t, N), amod(bv_expr, e, N));
else if (a.is_idiv(x, t, e) && a.is_numeral(t, v) && 0 <= v && v < N && is_non_negative(bv_expr, e))
r = x;
else if (a.is_mod(x, t, e) && a.is_numeral(t, v) && 0 <= v && v < N)
r = x;
else if (a.is_numeral(x, v))
r = a.mk_int(mod(v, N));
else if (is_bounded(x, N))
r = x;
else
r = a.mk_mod(x, a.mk_int(N));
return r;
}
rational solver::bv_size(expr* bv_expr) {
return rational::power_of_two(bv.get_bv_size(bv_expr->get_sort()));
}
void solver::translate_expr(expr* e) {
if (is_quantifier(e))
translate_quantifier(to_quantifier(e));
else if (is_var(e))
translate_var(to_var(e));
else {
app* ap = to_app(e);
if (m_is_plugin && ap->get_family_id() == basic_family_id && m.is_bool(ap)) {
set_translated(e, e);
return;
}
m_args.reset();
for (auto arg : *ap)
m_args.push_back(translated(arg));
if (ap->get_family_id() == basic_family_id)
translate_basic(ap);
else if (ap->get_family_id() == bv.get_family_id())
translate_bv(ap);
else
translate_app(ap);
}
}
void solver::translate_quantifier(quantifier* q) {
if (m_is_plugin) {
set_translated(q, q);
return;
}
if (is_lambda(q))
throw default_exception("lambdas are not supported in intblaster");
expr* b = q->get_expr();
unsigned nd = q->get_num_decls();
ptr_vector<sort> sorts;
for (unsigned i = 0; i < nd; ++i) {
auto s = q->get_decl_sort(i);
if (bv.is_bv_sort(s)) {
NOT_IMPLEMENTED_YET();
sorts.push_back(a.mk_int());
}
else
sorts.push_back(s);
}
b = translated(b);
// TODO if sorts contain integer, then created bounds variables.
set_translated(q, m.update_quantifier(q, b));
}
void solver::translate_var(var* v) {
if (bv.is_bv_sort(v->get_sort()))
set_translated(v, m.mk_var(v->get_idx(), a.mk_int()));
else
set_translated(v, v);
}
// Translate functions that are not built-in or bit-vectors.
// Base method uses fresh functions.
// Other method could use bv2int, int2bv axioms and coercions.
// f(args) = bv2int(f(int2bv(args'))
//
void solver::translate_app(app* e) {
if (m_is_plugin && m.is_bool(e)) {
set_translated(e, e);
return;
}
bool has_bv_sort = bv.is_bv(e);
func_decl* f = e->get_decl();
for (unsigned i = 0; i < m_args.size(); ++i)
if (bv.is_bv(e->get_arg(i)))
m_args[i] = bv.mk_int2bv(bv.get_bv_size(e->get_arg(i)), m_args.get(i));
if (has_bv_sort)
m_vars.push_back(e);
if (m_is_plugin) {
expr* r = m.mk_app(f, m_args);
if (has_bv_sort) {
ctx.push(push_back_vector(m_vars));
r = bv.mk_bv2int(r);
}
set_translated(e, r);
return;
}
else if (has_bv_sort) {
if (f->get_family_id() != null_family_id)
throw default_exception("conversion for interpreted functions is not supported by intblast solver");
func_decl* g = nullptr;
if (!m_new_funs.find(f, g)) {
g = m.mk_fresh_func_decl(e->get_decl()->get_name(), symbol("bv"), f->get_arity(), f->get_domain(), a.mk_int());
m_new_funs.insert(f, g);
}
f = g;
m_pinned.push_back(f);
}
set_translated(e, m.mk_app(f, m_args));
}
void solver::translate_bv(app* e) {
auto bnot = [&](expr* e) {
return a.mk_sub(a.mk_int(-1), e);
};
auto band = [&](expr_ref_vector const& args) {
expr* r = arg(0);
for (unsigned i = 1; i < args.size(); ++i)
r = a.mk_band(bv.get_bv_size(e), r, arg(i));
return r;
};
auto rotate_left = [&](unsigned n) {
auto sz = bv.get_bv_size(e);
n = n % sz;
expr* r = arg(0);
if (n != 0 && sz != 1) {
// r[sz - n - 1 : 0] ++ r[sz - 1 : sz - n]
// r * 2^(sz - n) + (r div 2^n) mod 2^(sz - n)???
// r * A + (r div B) mod A
auto N = bv_size(e);
auto A = rational::power_of_two(sz - n);
auto B = rational::power_of_two(n);
auto hi = mul(r, a.mk_int(A));
auto lo = amod(e, a.mk_idiv(umod(e, 0), a.mk_int(B)), A);
r = add(hi, lo);
}
return r;
};
expr* bv_expr = e;
expr_ref r(m);
auto const& args = m_args;
switch (e->get_decl_kind()) {
case OP_BADD:
r = a.mk_add(args);
break;
case OP_BSUB:
r = a.mk_sub(args.size(), args.data());
break;
case OP_BMUL:
r = a.mk_mul(args);
break;
case OP_ULEQ:
bv_expr = e->get_arg(0);
r = a.mk_le(umod(bv_expr, 0), umod(bv_expr, 1));
break;
case OP_UGEQ:
bv_expr = e->get_arg(0);
r = a.mk_ge(umod(bv_expr, 0), umod(bv_expr, 1));
break;
case OP_ULT:
bv_expr = e->get_arg(0);
r = a.mk_lt(umod(bv_expr, 0), umod(bv_expr, 1));
break;
case OP_UGT:
bv_expr = e->get_arg(0);
r = a.mk_gt(umod(bv_expr, 0), umod(bv_expr, 1));
break;
case OP_SLEQ:
bv_expr = e->get_arg(0);
r = a.mk_le(smod(bv_expr, 0), smod(bv_expr, 1));
break;
case OP_SGEQ:
bv_expr = e->get_arg(0);
r = a.mk_ge(smod(bv_expr, 0), smod(bv_expr, 1));
break;
case OP_SLT:
bv_expr = e->get_arg(0);
r = a.mk_lt(smod(bv_expr, 0), smod(bv_expr, 1));
break;
case OP_SGT:
bv_expr = e->get_arg(0);
r = a.mk_gt(smod(bv_expr, 0), smod(bv_expr, 1));
break;
case OP_BNEG:
r = a.mk_uminus(arg(0));
break;
case OP_CONCAT: {
unsigned sz = 0;
expr_ref new_arg(m);
for (unsigned i = args.size(); i-- > 0;) {
expr* old_arg = e->get_arg(i);
new_arg = umod(old_arg, i);
if (sz > 0) {
new_arg = mul(new_arg, a.mk_int(rational::power_of_two(sz)));
r = add(r, new_arg);
}
else
r = new_arg;
sz += bv.get_bv_size(old_arg->get_sort());
}
break;
}
case OP_EXTRACT: {
unsigned lo, hi;
expr* old_arg;
VERIFY(bv.is_extract(e, lo, hi, old_arg));
r = arg(0);
if (lo > 0)
r = a.mk_idiv(r, a.mk_int(rational::power_of_two(lo)));
break;
}
case OP_BV_NUM: {
rational val;
unsigned sz;
VERIFY(bv.is_numeral(e, val, sz));
r = a.mk_int(val);
break;
}
case OP_BUREM:
case OP_BUREM_I: {
expr* x = umod(e, 0), * y = umod(e, 1);
r = if_eq(y, 0, x, a.mk_mod(x, y));
break;
}
case OP_BUDIV:
case OP_BUDIV_I: {
expr* x = umod(e, 0), * y = umod(e, 1);
r = if_eq(y, 0, a.mk_int(-1), a.mk_idiv(x, y));
break;
}
case OP_BUMUL_NO_OVFL: {
bv_expr = e->get_arg(0);
r = a.mk_lt(mul(umod(bv_expr, 0), umod(bv_expr, 1)), a.mk_int(bv_size(bv_expr)));
break;
}
case OP_BSHL: {
if (!a.is_numeral(arg(0)) && !a.is_numeral(arg(1)))
r = a.mk_shl(bv.get_bv_size(e), arg(0),arg(1));
else {
expr* x = arg(0), * y = umod(e, 1);
r = a.mk_int(0);
IF_VERBOSE(2, verbose_stream() << "shl " << mk_bounded_pp(e, m) << " " << bv.get_bv_size(e) << "\n");
for (unsigned i = 0; i < bv.get_bv_size(e); ++i)
r = if_eq(y, i, mul(x, a.mk_int(rational::power_of_two(i))), r);
}
break;
}
case OP_BNOT:
r = bnot(arg(0));
break;
case OP_BLSHR:
if (!a.is_numeral(arg(0)) && !a.is_numeral(arg(1)))
r = a.mk_lshr(bv.get_bv_size(e), arg(0), arg(1));
else {
expr* x = arg(0), * y = umod(e, 1);
r = a.mk_int(0);
IF_VERBOSE(2, verbose_stream() << "lshr " << mk_bounded_pp(e, m) << " " << bv.get_bv_size(e) << "\n");
for (unsigned i = 0; i < bv.get_bv_size(e); ++i)
r = if_eq(y, i, a.mk_idiv(x, a.mk_int(rational::power_of_two(i))), r);
}
break;
case OP_BASHR:
if (!a.is_numeral(arg(1)))
r = a.mk_ashr(bv.get_bv_size(e), arg(0), arg(1));
else {
//
// ashr(x, y)
// if y = k & x >= 0 -> x / 2^k
// if y = k & x < 0 -> (x / 2^k) - 2^{N-k}
//
unsigned sz = bv.get_bv_size(e);
rational N = bv_size(e);
expr* x = umod(e, 0), *y = umod(e, 1);
expr* signx = a.mk_ge(x, a.mk_int(N / 2));
r = m.mk_ite(signx, a.mk_int(- 1), a.mk_int(0));
IF_VERBOSE(1, verbose_stream() << "ashr " << mk_bounded_pp(e, m) << " " << bv.get_bv_size(e) << "\n");
for (unsigned i = 0; i < sz; ++i) {
expr* d = a.mk_idiv(x, a.mk_int(rational::power_of_two(i)));
r = if_eq(y, i,
m.mk_ite(signx, add(d, a.mk_int(- rational::power_of_two(sz-i))), d),
r);
}
}
break;
case OP_BOR:
// p | q := (p + q) - band(p, q)
IF_VERBOSE(2, verbose_stream() << "bor " << mk_bounded_pp(e, m) << " " << bv.get_bv_size(e) << "\n");
r = arg(0);
for (unsigned i = 1; i < args.size(); ++i)
r = a.mk_sub(add(r, arg(i)), a.mk_band(bv.get_bv_size(e), r, arg(i)));
break;
case OP_BNAND:
r = bnot(band(args));
break;
case OP_BAND:
IF_VERBOSE(2, verbose_stream() << "band " << mk_bounded_pp(e, m) << " " << bv.get_bv_size(e) << "\n");
r = band(args);
break;
case OP_BXNOR:
case OP_BXOR: {
// p ^ q := (p + q) - 2*band(p, q);
unsigned sz = bv.get_bv_size(e);
IF_VERBOSE(2, verbose_stream() << "bxor " << bv.get_bv_size(e) << "\n");
r = arg(0);
for (unsigned i = 1; i < args.size(); ++i) {
expr* q = arg(i);
r = a.mk_sub(add(r, q), mul(a.mk_int(2), a.mk_band(sz, r, q)));
}
if (e->get_decl_kind() == OP_BXNOR)
r = bnot(r);
break;
}
case OP_ZERO_EXT:
bv_expr = e->get_arg(0);
r = umod(bv_expr, 0);
SASSERT(bv.get_bv_size(e) >= bv.get_bv_size(bv_expr));
break;
case OP_SIGN_EXT: {
bv_expr = e->get_arg(0);
r = umod(bv_expr, 0);
SASSERT(bv.get_bv_size(e) >= bv.get_bv_size(bv_expr));
unsigned arg_sz = bv.get_bv_size(bv_expr);
//unsigned sz = bv.get_bv_size(e);
// rational N = rational::power_of_two(sz);
rational M = rational::power_of_two(arg_sz);
expr* signbit = a.mk_ge(r, a.mk_int(M / 2));
r = m.mk_ite(signbit, a.mk_sub(r, a.mk_int(M)), r);
break;
}
case OP_INT2BV:
m_int2bv.push_back(e);
ctx.push(push_back_vector(m_int2bv));
r = arg(0);
break;
case OP_BV2INT:
m_bv2int.push_back(e);
ctx.push(push_back_vector(m_bv2int));
r = umod(e->get_arg(0), 0);
break;
case OP_BCOMP:
bv_expr = e->get_arg(0);
r = m.mk_ite(m.mk_eq(umod(bv_expr, 0), umod(bv_expr, 1)), a.mk_int(1), a.mk_int(0));
break;
case OP_BSMOD_I:
case OP_BSMOD: {
expr* x = umod(e, 0), *y = umod(e, 1);
rational N = bv_size(e);
expr* signx = a.mk_ge(x, a.mk_int(N/2));
expr* signy = a.mk_ge(y, a.mk_int(N/2));
expr* u = a.mk_mod(x, y);
// u = 0 -> 0
// y = 0 -> x
// x < 0, y < 0 -> -u
// x < 0, y >= 0 -> y - u
// x >= 0, y < 0 -> y + u
// x >= 0, y >= 0 -> u
r = a.mk_uminus(u);
r = m.mk_ite(m.mk_and(m.mk_not(signx), signy), add(u, y), r);
r = m.mk_ite(m.mk_and(signx, m.mk_not(signy)), a.mk_sub(y, u), r);
r = m.mk_ite(m.mk_and(m.mk_not(signx), m.mk_not(signy)), u, r);
r = if_eq(u, 0, a.mk_int(0), r);
r = if_eq(y, 0, x, r);
break;
}
case OP_BSDIV_I:
case OP_BSDIV: {
// d = udiv(abs(x), abs(y))
// y = 0, x > 0 -> 1
// y = 0, x <= 0 -> -1
// x = 0, y != 0 -> 0
// x > 0, y < 0 -> -d
// x < 0, y > 0 -> -d
// x > 0, y > 0 -> d
// x < 0, y < 0 -> d
expr* x = umod(e, 0), * y = umod(e, 1);
rational N = bv_size(e);
expr* signx = a.mk_ge(x, a.mk_int(N / 2));
expr* signy = a.mk_ge(y, a.mk_int(N / 2));
x = m.mk_ite(signx, a.mk_sub(a.mk_int(N), x), x);
y = m.mk_ite(signy, a.mk_sub(a.mk_int(N), y), y);
expr* d = a.mk_idiv(x, y);
r = m.mk_ite(m.mk_iff(signx, signy), d, a.mk_uminus(d));
r = if_eq(y, 0, m.mk_ite(signx, a.mk_int(1), a.mk_int(-1)), r);
break;
}
case OP_BSREM_I:
case OP_BSREM: {
// y = 0 -> x
// else x - sdiv(x, y) * y
expr* x = umod(e, 0), * y = umod(e, 1);
rational N = bv_size(e);
expr* signx = a.mk_ge(x, a.mk_int(N / 2));
expr* signy = a.mk_ge(y, a.mk_int(N / 2));
expr* absx = m.mk_ite(signx, a.mk_sub(a.mk_int(N), x), x);
expr* absy = m.mk_ite(signy, a.mk_sub(a.mk_int(N), y), y);
expr* d = a.mk_idiv(absx, absy);
d = m.mk_ite(m.mk_iff(signx, signy), d, a.mk_uminus(d));
r = a.mk_sub(x, mul(d, y));
r = if_eq(y, 0, x, r);
break;
}
case OP_ROTATE_LEFT: {
auto n = e->get_parameter(0).get_int();
r = rotate_left(n);
break;
}
case OP_ROTATE_RIGHT: {
unsigned sz = bv.get_bv_size(e);
auto n = e->get_parameter(0).get_int();
r = rotate_left(sz - n);
break;
}
case OP_EXT_ROTATE_LEFT: {
unsigned sz = bv.get_bv_size(e);
expr* y = umod(e, 1);
r = a.mk_int(0);
for (unsigned i = 0; i < sz; ++i)
r = if_eq(y, i, rotate_left(i), r);
break;
}
case OP_EXT_ROTATE_RIGHT: {
unsigned sz = bv.get_bv_size(e);
expr* y = umod(e, 1);
r = a.mk_int(0);
for (unsigned i = 0; i < sz; ++i)
r = if_eq(y, i, rotate_left(sz - i), r);
break;
}
case OP_REPEAT: {
unsigned n = e->get_parameter(0).get_int();
expr* x = umod(e->get_arg(0), 0);
r = x;
rational N = bv_size(e->get_arg(0));
rational N0 = N;
for (unsigned i = 1; i < n; ++i)
r = add(mul(a.mk_int(N), x), r), N *= N0;
break;
}
case OP_BREDOR: {
r = umod(e->get_arg(0), 0);
r = m.mk_not(m.mk_eq(r, a.mk_int(0)));
break;
}
case OP_BREDAND: {
rational N = bv_size(e->get_arg(0));
r = umod(e->get_arg(0), 0);
r = m.mk_not(m.mk_eq(r, a.mk_int(N - 1)));
break;
}
default:
verbose_stream() << mk_pp(e, m) << "\n";
NOT_IMPLEMENTED_YET();
}
set_translated(e, r);
}
expr_ref solver::if_eq(expr* n, unsigned k, expr* th, expr* el) {
rational r;
expr_ref _th(th, m), _el(el, m);
if (bv.is_numeral(n, r)) {
if (r == k)
return expr_ref(th, m);
else
return expr_ref(el, m);
}
return expr_ref(m.mk_ite(m.mk_eq(n, a.mk_int(k)), th, el), m);
}
void solver::translate_basic(app* e) {
if (m.is_eq(e)) {
bool has_bv_arg = any_of(*e, [&](expr* arg) { return bv.is_bv(arg); });
if (has_bv_arg) {
expr* bv_expr = e->get_arg(0);
rational N = rational::power_of_two(bv.get_bv_size(bv_expr));
if (a.is_numeral(arg(0)) || a.is_numeral(arg(1)) ||
is_bounded(arg(0), N) || is_bounded(arg(1), N)) {
set_translated(e, m.mk_eq(umod(bv_expr, 0), umod(bv_expr, 1)));
}
else {
m_args[0] = a.mk_sub(arg(0), arg(1));
set_translated(e, m.mk_eq(umod(bv_expr, 0), a.mk_int(0)));
}
}
else
set_translated(e, m.mk_eq(arg(0), arg(1)));
}
else if (m.is_ite(e))
set_translated(e, m.mk_ite(arg(0), arg(1), arg(2)));
else if (m_is_plugin)
set_translated(e, e);
else
set_translated(e, m.mk_app(e->get_decl(), m_args));
}
rational solver::get_value(expr* e) const {
SASSERT(bv.is_bv(e));
model_ref mdl;
m_solver->get_model(mdl);
expr_ref r(m);
r = translated(e);
r = m_translator.translated(e);
rational val;
if (!mdl->eval_expr(r, r, true))
return rational::zero();
@ -1099,7 +465,7 @@ namespace intblast {
}
rational r, N = rational::power_of_two(bv.get_bv_size(e));
expr* te = translated(e);
expr* te = m_translator.translated(e);
model_ref mdlr;
m_solver->get_model(mdlr);
expr_ref value(m);
@ -1126,14 +492,12 @@ namespace intblast {
else {
expr_ref bv2int(bv.mk_bv2int(n->get_expr()), m);
euf::enode* b2i = ctx.get_enode(bv2int);
if (!b2i) verbose_stream() << bv2int << "\n";
SASSERT(b2i);
VERIFY(b2i);
arith::arith_value av(ctx);
rational r;
VERIFY(av.get_value(b2i->get_expr(), r));
value = bv.mk_numeral(r, bv.get_bv_size(n->get_expr()));
verbose_stream() << ctx.bpp(n) << " := " << value << "\n";
}
values.set(n->get_root_id(), value);
TRACE("model", tout << "add_value " << ctx.bpp(n) << " := " << value << "\n");
@ -1143,11 +507,11 @@ namespace intblast {
return;
for (auto n : ctx.get_egraph().nodes()) {
auto e = n->get_expr();
if (!is_translated(e))
if (!m_translator.is_translated(e))
continue;
if (!bv.is_bv(e))
continue;
auto t = translated(e);
auto t = m_translator.translated(e);
expr_ref ei(bv.mk_bv2int(e), m);
expr_ref ti(a.mk_mod(t, a.mk_int(rational::power_of_two(bv.get_bv_size(e)))), m);

52
src/sat/smt/intblast_solver.h
View file

@ -38,6 +38,7 @@ Author:
#include "solver/solver.h"
#include "sat/smt/sat_th.h"
#include "util/statistics.h"
#include "ast/rewriter/bv2int_translator.h"
namespace euf {
class solver;
@ -45,18 +46,31 @@ namespace euf {
namespace intblast {
class translator_trail : public bv2int_translator_trail {
euf::solver& ctx;
public:
translator_trail(euf::solver& ctx):ctx(ctx) {}
void push(push_back_vector<expr_ref_vector> const& c) override;
void push(push_back_vector<ptr_vector<app>> const& c) override;
void push_idx(set_vector_idx_trail<expr_ref_vector> const& c) override;
};
class solver : public euf::th_euf_solver {
euf::solver& ctx;
sat::solver& s;
ast_manager& m;
bv_util bv;
arith_util a;
translator_trail trail;
bv2int_translator m_translator;
scoped_ptr<::solver> m_solver;
obj_map<func_decl, func_decl*> m_new_funs;
expr_ref_vector m_translate, m_args;
ast_ref_vector m_pinned;
//obj_map<func_decl, func_decl*> m_new_funs;
//expr_ref_vector m_translate, m_args;
//ast_ref_vector m_pinned;
sat::literal_vector m_core;
ptr_vector<app> m_bv2int, m_int2bv;
// ptr_vector<app> m_bv2int, m_int2bv;
statistics m_stats;
bool m_is_plugin = true; // when the solver is used as a plugin, then do not translate below quantifiers.
@ -66,33 +80,6 @@ namespace intblast {
bool is_translated(expr* e) const { return !!m_translate.get(e->get_id(), nullptr); }
expr* translated(expr* e) const { expr* r = m_translate.get(e->get_id(), nullptr); SASSERT(r); return r; }
void set_translated(expr* e, expr* r);
expr* arg(unsigned i) { return m_args.get(i); }
expr* umod(expr* bv_expr, unsigned i);
expr* smod(expr* bv_expr, unsigned i);
bool is_bounded(expr* v, rational const& N);
bool is_non_negative(expr* bv_expr, expr* e);
expr_ref mul(expr* x, expr* y);
expr_ref add(expr* x, expr* y);
expr_ref if_eq(expr* n, unsigned k, expr* th, expr* el);
expr* amod(expr* bv_expr, expr* x, rational const& N);
rational bv_size(expr* bv_expr);
void translate_expr(expr* e);
void translate_bv(app* e);
void translate_basic(app* e);
void translate_app(app* e);
void translate_quantifier(quantifier* q);
void translate_var(var* v);
void ensure_translated(expr* e);
void internalize_bv(app* e);
unsigned m_vars_qhead = 0, m_preds_qhead = 0;
ptr_vector<expr> m_vars, m_preds;
bool add_bound_axioms();
bool add_predicate_axioms();
@ -101,6 +88,9 @@ namespace intblast {
void add_value_plugin(euf::enode* n, model& mdl, expr_ref_vector& values);
void add_value_solver(euf::enode* n, model& mdl, expr_ref_vector& values);
unsigned m_vars_qhead = 0, m_preds_qhead = 0;
public:
solver(euf::solver& ctx);

5
src/sat/smt/sat_th.h
View file

@ -18,7 +18,6 @@ Author:
#include "util/top_sort.h"
#include "sat/smt/sat_smt.h"
#include "sat/sat_ddfw.h"
#include "ast/euf/euf_egraph.h"
#include "model/model.h"
#include "smt/params/smt_params.h"
@ -139,10 +138,6 @@ namespace euf {
virtual euf::enode_pair get_justification_eq(size_t j);
/**
* Local search interface
*/
virtual void set_bool_search(sat::ddfw* ddfw) {}
virtual void set_bounds_begin() {}

192
src/sat/smt/sls_solver.cpp
View file

@ -13,154 +13,118 @@ Author:
Nikolaj Bjorner (nbjorner) 2024-02-21
--*/
#include "sat/smt/sls_solver.h"
#include "sat/smt/euf_solver.h"
#include "ast/sls/sls_context.h"
#include "ast/for_each_expr.h"
namespace sls {
#ifdef SINGLE_THREAD
solver::solver(euf::solver& ctx) :
th_euf_solver(ctx, symbol("sls"), ctx.get_manager().mk_family_id("sls"))
{}
{}
#ifdef SINGLE_THREAD
#else
solver::solver(euf::solver& ctx):
th_euf_solver(ctx, symbol("sls"), ctx.get_manager().mk_family_id("sls"))
{}
solver::~solver() {
finalize();
}
void solver::finalize() {
if (!m_completed && m_sls) {
m_sls->cancel();
m_thread.join();
m_sls->collect_statistics(m_st);
m_sls = nullptr;
m_shared = nullptr;
m_slsm = nullptr;
m_units = nullptr;
}
params_ref solver::get_params() {
return s().params();
}
sat::check_result solver::check() {
return sat::check_result::CR_DONE;
void solver::initialize_value(expr* t, expr* v) {
ctx.user_propagate_initialize_value(t, v);
}
void solver::force_phase(sat::literal lit) {
ctx.s().set_phase(lit);
}
void solver::set_has_new_best_phase(bool b) {
}
bool solver::get_best_phase(sat::bool_var v) {
return false;
}
expr* solver::bool_var2expr(sat::bool_var v) {
return ctx.bool_var2expr(v);
}
void solver::set_finished() {
ctx.s().set_canceled();
}
unsigned solver::get_num_bool_vars() const {
return s().num_vars();
}
void solver::finalize() {
if (!m_smt_plugin)
return;
m_smt_plugin->finalize(m_model, m_st);
m_model = nullptr;
m_smt_plugin = nullptr;
}
bool solver::unit_propagate() {
force_push();
sample_local_search();
return false;
}
bool solver::is_unit(expr* e) {
if (!e)
return false;
m.is_not(e, e);
if (is_uninterp_const(e))
if (m_smt_plugin && !m_checking) {
expr_ref_vector fmls(m);
m_checking = true;
m_smt_plugin->check(fmls, ctx.top_level_clauses());
return true;
bv_util bu(m);
expr* s;
if (bu.is_bit2bool(e, s))
return is_uninterp_const(s);
return false;
}
if (!m_smt_plugin)
return false;
if (!m_smt_plugin->completed())
return false;
m_smt_plugin->finalize(m_model, m_st);
m_smt_plugin = nullptr;
return true;
}
void solver::pop_core(unsigned n) {
for (; m_trail_lim < s().init_trail_size(); ++m_trail_lim) {
auto lit = s().trail_literal(m_trail_lim);
auto e = ctx.literal2expr(lit);
if (is_unit(e)) {
// IF_VERBOSE(1, verbose_stream() << "add unit " << mk_pp(e, m) << "\n");
std::lock_guard<std::mutex> lock(m_mutex);
ast_translation tr(m, *m_shared);
m_units->push_back(tr(e.get()));
m_has_units = true;
if (!m_smt_plugin)
return;
unsigned scope_lvl = s().scope_lvl();
if (s().search_lvl() == scope_lvl - n) {
for (; m_trail_lim < s().init_trail_size(); ++m_trail_lim) {
auto lit = s().trail_literal(m_trail_lim);
m_smt_plugin->add_unit(lit);
}
}
}
#if 0
if (ctx.has_new_best_phase())
m_smt_plugin->import_phase_from_smt();
#endif
m_smt_plugin->import_from_sls();
}
void solver::init_search() {
if (m_sls) {
m_sls->cancel();
m_thread.join();
m_result = l_undef;
m_completed = false;
m_has_units = false;
m_model = nullptr;
m_units = nullptr;
}
// set up state for local search solver here
m_shared = alloc(ast_manager);
m_slsm = alloc(ast_manager);
m_units = alloc(expr_ref_vector, *m_shared);
ast_translation tr(m, *m_slsm);
m_completed = false;
m_result = l_undef;
m_model = nullptr;
m_sls = alloc(bv::sls, *m_slsm, s().params());
for (expr* a : ctx.get_assertions())
m_sls->assert_expr(tr(a));
std::function<bool(expr*, unsigned)> eval = [&](expr* e, unsigned r) {
return false;
};
m_sls->init();
m_sls->init_eval(eval);
m_sls->updt_params(s().params());
m_sls->init_unit([&]() {
if (!m_has_units)
return expr_ref(*m_slsm);
expr_ref e(*m_slsm);
{
std::lock_guard<std::mutex> lock(m_mutex);
if (m_units->empty())
return expr_ref(*m_slsm);
ast_translation tr(*m_shared, *m_slsm);
e = tr(m_units->back());
m_units->pop_back();
}
return e;
});
m_sls->set_model([&](model& mdl) {
std::lock_guard<std::mutex> lock(m_mutex);
ast_translation tr(*m_shared, m);
m_model = mdl.translate(tr);
});
m_thread = std::thread([this]() { run_local_search(); });
if (m_smt_plugin)
finalize();
m_smt_plugin = alloc(sls::smt_plugin, *this);
m_checking = false;
}
void solver::sample_local_search() {
if (!m_completed)
return;
m_thread.join();
m_completed = false;
m_sls->collect_statistics(m_st);
if (m_result == l_true) {
IF_VERBOSE(2, verbose_stream() << "(sat.sls :model-completed)\n";);
auto mdl = m_sls->get_model();
ast_translation tr(*m_slsm, m);
m_model = mdl->translate(tr);
s().set_canceled();
}
m_sls = nullptr;
}
void solver::run_local_search() {
m_result = (*m_sls)();
m_completed = true;
std::ostream& solver::display(std::ostream& out) const {
return out << "theory-sls\n";
}
#endif
}

40
src/sat/smt/sls_solver.h
View file

@ -18,7 +18,7 @@ Author:
#include "util/rlimit.h"
#include "ast/sls/bv_sls.h"
#include "ast/sls/sat_ddfw.h"
#include "sat/smt/sat_th.h"
@ -52,8 +52,7 @@ namespace sls {
#else
#include <thread>
#include <mutex>
#include "ast/sls/sls_smt_plugin.h"
namespace euf {
class solver;
@ -61,24 +60,12 @@ namespace euf {
namespace sls {
class solver : public euf::th_euf_solver {
std::atomic<lbool> m_result;
std::atomic<bool> m_completed, m_has_units;
std::thread m_thread;
std::mutex m_mutex;
// m is accessed by the main thread
// m_slsm is accessed by the sls thread
// m_shared is only accessed at synchronization points
scoped_ptr<ast_manager> m_shared, m_slsm;
scoped_ptr<bv::sls> m_sls;
scoped_ptr<expr_ref_vector> m_units;
class solver : public euf::th_euf_solver, public sls::smt_context {
model_ref m_model;
sls::smt_plugin* m_smt_plugin = nullptr;
unsigned m_trail_lim = 0;
statistics m_st;
void run_local_search();
void sample_local_search();
bool is_unit(expr*);
bool m_checking = false;
::statistics m_st;
public:
solver(euf::solver& ctx);
@ -97,10 +84,21 @@ namespace sls {
sat::literal internalize(expr* e, bool sign, bool root) override { UNREACHABLE(); return sat::null_literal; }
void internalize(expr* e) override { UNREACHABLE(); }
void get_antecedents(sat::literal l, sat::ext_justification_idx idx, sat::literal_vector & r, bool probing) override { UNREACHABLE(); }
sat::check_result check() override;
std::ostream & display(std::ostream & out) const override { return out; }
sat::check_result check() override { return sat::check_result::CR_DONE; }
std::ostream& display(std::ostream& out) const override;
std::ostream & display_justification(std::ostream & out, sat::ext_justification_idx idx) const override { UNREACHABLE(); return out; }
std::ostream & display_constraint(std::ostream & out, sat::ext_constraint_idx idx) const override { UNREACHABLE(); return out; }
ast_manager& get_manager() override { return m; }
params_ref get_params() override;
void initialize_value(expr* t, expr* v) override;
void force_phase(sat::literal lit) override;
void set_has_new_best_phase(bool b) override;
bool get_best_phase(sat::bool_var v) override;
expr* bool_var2expr(sat::bool_var v) override;
void set_finished() override;
unsigned get_num_bool_vars() const override;
};

15
src/sat/tactic/goal2sat.cpp
View file

@ -44,7 +44,7 @@ Notes:
#include "sat/smt/pb_solver.h"
#include "sat/smt/euf_solver.h"
#include "sat/smt/sat_th.h"
#include "sat/sat_params.hpp"
#include "params/sat_params.hpp"
#include<sstream>
struct goal2sat::imp : public sat::sat_internalizer {
@ -139,10 +139,6 @@ struct goal2sat::imp : public sat::sat_internalizer {
return m_euf && ensure_euf()->relevancy_enabled();
}
bool top_level_relevant() {
return m_top_level && relevancy_enabled();
}
void mk_clause(sat::literal l1, sat::literal l2, euf::th_proof_hint* ph) {
sat::literal lits[2] = { l1, l2 };
mk_clause(2, lits, ph);
@ -158,6 +154,7 @@ struct goal2sat::imp : public sat::sat_internalizer {
if (relevancy_enabled())
ensure_euf()->add_aux(n, lits);
m_solver.add_clause(n, lits, mk_status(ph));
add_top_level_clause(n, lits);
}
void mk_root_clause(sat::literal l) {
@ -179,6 +176,7 @@ struct goal2sat::imp : public sat::sat_internalizer {
if (relevancy_enabled())
ensure_euf()->add_root(n, lits);
m_solver.add_clause(n, lits, ph ? mk_status(ph) : sat::status::input());
add_top_level_clause(n, lits);
}
sat::bool_var add_var(bool is_ext, expr* n) {
@ -895,7 +893,6 @@ struct goal2sat::imp : public sat::sat_internalizer {
process(n, true);
CTRACE("goal2sat", !m_result_stack.empty(), tout << m_result_stack << "\n";);
SASSERT(m_result_stack.empty());
add_assertion(n);
}
void insert_dep(expr* dep0, expr* dep, bool sign) {
@ -990,10 +987,12 @@ struct goal2sat::imp : public sat::sat_internalizer {
}
}
void add_assertion(expr* f) {
void add_top_level_clause(unsigned n, sat::literal const* lits) {
if (!m_top_level)
return;
auto* ext = dynamic_cast<euf::solver*>(m_solver.get_extension());
if (ext)
ext->add_assertion(f);
ext->add_clause(n, lits);
}
void update_model(model_ref& mdl) {

2
src/sat/tactic/sat2goal.cpp
View file

@ -44,7 +44,7 @@ Notes:
#include "sat/smt/pb_solver.h"
#include "sat/smt/euf_solver.h"
#include "sat/smt/sat_th.h"
#include "sat/sat_params.hpp"
#include "params/sat_params.hpp"
#include<sstream>
sat2goal::mc::mc(ast_manager& m): m(m), m_var2expr(m) {}

3
src/sat/tactic/sat_tactic.cpp
View file

@ -16,13 +16,14 @@ Author:
Notes:
--*/
#include "params/sat_params.hpp"
#include "ast/ast_pp.h"
#include "model/model_v2_pp.h"
#include "tactic/tactical.h"
#include "sat/tactic/goal2sat.h"
#include "sat/tactic/sat2goal.h"
#include "sat/sat_solver.h"
#include "sat/sat_params.hpp"
class sat_tactic : public tactic {

2
src/shell/dimacs_frontend.cpp
View file

@ -23,7 +23,7 @@ Revision History:
#include "util/rlimit.h"
#include "util/gparams.h"
#include "sat/dimacs.h"
#include "sat/sat_params.hpp"
#include "params/sat_params.hpp"
#include "sat/sat_solver.h"
#include "sat/tactic/goal2sat.h"
#include "sat/tactic/sat2goal.h"

2
src/smt/CMakeLists.txt
View file

@ -61,11 +61,13 @@ z3_add_component(smt
theory_dl.cpp
theory_dummy.cpp
theory_fpa.cpp
theory_intblast.cpp
theory_lra.cpp
theory_opt.cpp
theory_pb.cpp
theory_recfun.cpp
theory_seq.cpp
theory_sls.cpp
theory_special_relations.cpp
theory_str.cpp
theory_str_mc.cpp

23
src/smt/smt_context.cpp
View file

@ -37,6 +37,7 @@ Revision History:
#include "smt/uses_theory.h"
#include "smt/theory_special_relations.h"
#include "smt/theory_polymorphism.h"
#include "smt/theory_sls.h"
#include "smt/smt_for_each_relevant_expr.h"
#include "smt/smt_model_generator.h"
#include "smt/smt_model_checker.h"
@ -103,6 +104,10 @@ namespace smt {
*/
bool context::get_cancel_flag() {
if (l_true == m_sls_completed && !m.limit().suspended()) {
m_last_search_failure = CANCELED;
return true;
}
if (m.limit().inc())
return false;
m_last_search_failure = CANCELED;
@ -3503,9 +3508,13 @@ namespace smt {
m_case_split_queue->display(tout << "case splits\n");
);
display_profile(verbose_stream());
if (r == l_true && get_cancel_flag()) {
if (r == l_true && get_cancel_flag())
r = l_undef;
if (r == l_undef && m_sls_completed == l_true && has_sls_model()) {
m_last_search_failure = OK;
r = l_true;
}
m_sls_completed = l_false;
if (r == l_true && gparams::get_value("model_validate") == "true") {
recfun::util u(m);
if (u.get_rec_funs().empty() && m_proto_model) {
@ -3581,6 +3590,17 @@ namespace smt {
return r;
}
bool context::has_sls_model() {
if (!m_fparams.m_sls_enable)
return false;
auto tid = m.get_family_id("sls");
auto p = m_theories.get_plugin(tid);
if (!p)
return false;
m_model = dynamic_cast<theory_sls*>(p)->get_model();
return m_model.get() != nullptr;
}
/**
\brief Setup the logical context based on the current set of
asserted formulas and execute the check command.
@ -3734,6 +3754,7 @@ namespace smt {
m_phase_default = false;
m_case_split_queue ->init_search_eh();
m_next_progress_sample = 0;
m_sls_completed = l_undef;
if (m.has_type_vars() && !m_theories.get_plugin(poly_family_id))
register_plugin(alloc(theory_polymorphism, *this));
TRACE("literal_occ", display_literal_num_occs(tout););

11
src/smt/smt_context.h
View file

@ -128,6 +128,7 @@ namespace smt {
class parallel* m_par = nullptr;
unsigned m_par_index = 0;
bool m_internalizing_assertions = false;
lbool m_sls_completed = l_undef;
// -----------------------------------
@ -288,6 +289,11 @@ namespace smt {
bool get_cancel_flag();
void set_sls_completed() {
if (m_sls_completed == l_undef)
m_sls_completed = l_true;
}
region & get_region() {
return m_region;
}
@ -619,6 +625,9 @@ namespace smt {
friend class set_var_theory_trail;
void set_var_theory(bool_var v, theory_id tid);
bool has_sls_model();
// -----------------------------------
//
// Backtracking support
@ -939,6 +948,8 @@ namespace smt {
mk_th_clause(tid, num_lits, lits, num_params, params, CLS_TH_AXIOM);
}
void mk_th_axiom(theory_id tid, literal l1, unsigned num_params = 0, parameter * params = nullptr);
void mk_th_axiom(theory_id tid, literal l1, literal l2, unsigned num_params = 0, parameter * params = nullptr);
void mk_th_axiom(theory_id tid, literal l1, literal l2, literal l3, unsigned num_params = 0, parameter * params = nullptr);

4
src/smt/smt_internalizer.cpp
View file

@ -1562,6 +1562,10 @@ namespace smt {
mk_clause(num_lits, lits, js, k);
}
void context::mk_th_axiom(theory_id tid, literal l1, unsigned num_params, parameter * params) {
mk_th_axiom(tid, 1, &l1, num_params, params);
}
void context::mk_th_axiom(theory_id tid, literal l1, literal l2, unsigned num_params, parameter * params) {
literal ls[2] = { l1, l2 };
mk_th_axiom(tid, 2, ls, num_params, params);

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