* sat_literal: make constants constexpr
* dlist: rename elem -> list
* tbv: use get_bit
* additional pdd and rational tests
* egraph: callback setters take functions by value
This allows to set callbacks without defining a separate variable for
the callback lambda.
(previous usage does one copy of the function, exactly as before)
* cmake: enable compiler error when non-void function does not return value
plugin setting allows adding equality saturation within the E-graph propagation without involving externalizing theory solver dispatch. It makes equality saturation independent of SAT integration.
Add a special relation operator to support ad-hoc AC symbols.
observed perf overhead for QF_NIA is that assume_eqs in theory_lra incurs significant overhead when calling is_relevant_and_shared. The call to context::is_shared and the loop checking for beta redexes is a main bottleneck. The bottleneck is avoided by caching the result if is_shared inside the enode. It is invalidated for every merge/unmerge.
- increase build version to 4.12.1. This prepares updated release for MacOs-11 build on x86
- move literal propagation mode in euf-egraph to a callback and traversal of equivalence class. Track antecedent by newest equality instead of root. This makes equality propagation to literals have similar behavior as in legacy solver and appears to result in a speedup (10% fewer conflicts on QF_UF/QG-classification/qg5/iso_icl478.smt2 in preliminary testing)
- fix interaction of pre-processing and assumptions. Pre-processing has to freeze assumption literals so they don't get eliminated. This is similar to dependencies that are already frozen.
literals true/false are not necessarily created when the merge flag is set.
Also disable merge_tf for if-then-else expressions
Perhaps even not insert children of if expressions into congruence table?
perf fix for propagation behavior for equalities in the new core.
The old behavior was not to allow congruence closure on equalities.
The new behavior is to just not allow merging tf with equalities unless they appear somewhere in a foreign context (not under a Boolean operator)
The change re-surfaces merge_tf and enable_cgc distinction from the old core.
They can both be turned on or off.
merge_enabled renamed to cgc_enabled
The change is highly likely to introduce regressions in the new core.
Change propagation of literals from congruence:
- track antecedent enode. There are four ways to propagate
literals from the egraph.
- the literal is an equality and the two arguments are congruent
- the antecedent is merged with node n and the antecedent has a Boolean variable assignment.
- the antecedent is true or false, they are merged.
- the merge_tf flag is toggled to true but the node n has not been merged with true/false
- ensure mk_extract performs simplification to distribute over extract and removing extract if the range is the entire bit-vector
- ensure bool_rewriter simplifeis disjunctions when applicable.
move self-checking functionality to inside sat/smt so it can be used on-line and not just off-line.
when self-validation fails, use vs, not clause, to check. It allows self-validation without checking and maintaining RUP validation.
new options sat.smt.proof.check_rup, sat.smt.proof.check for online validation.
z3 sat.smt.proof.check=true sat.euf=true /v:1 sat.smt.proof.check_rup=true /st file.smt2 sat.smt.proof=p.smt2
EUF proofs are checked modulo union-find.
Equalities are added to to union-find if they are assumptions or if they can be derived using congruence closure. The congruence closure assumptions are added as proof-hints.
Note that this proof format does not track equality inferences, symmetry and transitivity. Instead they are handled by assuming a union-find based checker.