mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-07-24 05:08:55 +00:00
Code Activity

Seq rewriter integration (#4597)

Browse source 
* std::cout debugging statements

* comment out std::cout debugging as this is now a shared fork

* convert std::cout to TRACE statements for seq_rewriter and seq_regex

* add cases to min_length and max_length for regexes

* bug fix

* update min_length and max_length functions for REs

* initial pass on simplifying derivative normal forms by eliminating redundant predicates locally

* add seq_regex_brief trace statements

* working on debugging ref count issue

* fix ref count bug and convert trace statements to seq_regex_brief

* add compact tracing for cache hits/misses

* seq_regex fix cache hit/miss tracing and wrapper around is_nullable

* minor

* label and disable more experimental changes for testing

* minor documentation / tracing

* a few more @EXP annotations

* dead state elimination skeleton code

* progress on dead state elimination

* more progress on dead state elimination

* refactor dead state class to separate self-contained state_graph class

* finish factoring state_graph to only work with unsigned values, and implement separate functionality for expr* logic

* implement get_all_derivatives, add debug tracing

* trace statements for debugging is_nullable loop bug

* fix is_nullable loop bug

* comment out local nullable change and mark experimental

* pretty printing for state_graph

* rewrite state graph to remove the fragile assumption that all edges from a state are added at a time

* start of general cycle detection check + fix some comments

* implement full cycle detection procedure

* normalize derivative conditions to form 'ele <= a'

* order derivative conditions by character code

* fix confusing names m_to and m_from

* assign increasing state IDs from 1 instead of using get_id on AST node

* remove elim_condition call in get_dall_derivatives

* use u_map instead of uint_map to avoid memory leak

* remove unnecessary call to is_ground

* debugging

* small improvements to seq_regex_brief tracing

* fix bug on evil2 example

* save work

* new propagate code

* work in progress on using same seq sort for deriv calls

* avoid re-computing derivatives: use same head var for every derivative call

* use min_length on regexes to prune search

* simple implementation of can_be_in_cycle using rank function idea

* add a disabled experimental change

* minor cleanup comments, etc.

* seq_rewriter cleanup for PR

* remove cache hit/miss counts tracing

* remove changes not in the rewriter

* remove cache hit/miss count tracing

Co-authored-by: calebstanford-msr <t-casta@microsoft.com>
Co-authored-by: Caleb Stanford <caleb.pirsquared@gmail.com>
This commit is contained in:
Nikolaj Bjorner 2020-07-27 18:08:51 -07:00 • committed by GitHub
parent 2fb914d2a2
commit e90f01006c
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
2 changed files with 225 additions and 31 deletions
Download patch file Download diff file Expand all files Collapse all files

12
src/ast/rewriter/seq_rewriter.h
View file

@ -182,7 +182,7 @@ class seq_rewriter {
expr_ref mk_seq_concat(expr* a, expr* b);
// Calculate derivative, memoized and enforcing a normal form
expr_ref mk_derivative(expr* ele, expr* r);
expr_ref is_nullable_rec(expr* r);
expr_ref mk_derivative_rec(expr* ele, expr* r);
expr_ref mk_der_op(decl_kind k, expr* a, expr* b);
expr_ref mk_der_op_rec(decl_kind k, expr* a, expr* b);
@ -190,8 +190,12 @@ class seq_rewriter {
expr_ref mk_der_union(expr* a, expr* b);
expr_ref mk_der_inter(expr* a, expr* b);
expr_ref mk_der_compl(expr* a);
expr_ref mk_der_reverse(expr* a);
expr_ref mk_der_cond(expr* cond, expr* ele, sort* seq_sort);
bool lt_char(expr* ch1, expr* ch2);
bool eq_char(expr* ch1, expr* ch2);
bool le_char(expr* ch1, expr* ch2);
bool pred_implies(expr* a, expr* b);
bool are_complements(expr* r1, expr* r2) const;
bool is_subset(expr* r1, expr* r2) const;
@ -283,7 +287,6 @@ class seq_rewriter {
class seq_util::str& str() { return u().str; }
class seq_util::str const& str() const { return u().str; }
expr_ref is_nullable_rec(expr* r);
void intersect(unsigned lo, unsigned hi, svector<std::pair<unsigned, unsigned>>& ranges);
public:
@ -330,8 +333,9 @@ public:
void add_seqs(expr_ref_vector const& ls, expr_ref_vector const& rs, expr_ref_pair_vector& new_eqs);
// Check for acceptance of the empty string
// Expose derivative and nullability check
expr_ref is_nullable(expr* r);
expr_ref mk_derivative(expr* ele, expr* r);
// heuristic elimination of element from condition that comes form a derivative.
// special case optimization for conjunctions of equalities, disequalities and ranges.