mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2026-02-18 14:44:21 +00:00
Code Activity

Begin reorganizing resolve_value

Browse source
This commit is contained in:
Jakob Rath 2021-09-07 11:40:50 +02:00
parent b4e14c31d0
commit 7d58296ad2
6 changed files with 113 additions and 25 deletions
Download patch file Download diff file Expand all files Collapse all files

24
src/math/polysat/conflict_core.cpp
View file

@ -165,6 +165,30 @@ namespace polysat {
return clause::from_literals(lvl, std::move(dep), std::move(literals));
}
bool conflict_core::resolve_value(pvar v, vector<signed_constraint> const& cjust_v) {
// TODO: maybe don't do this automatically, because cjust-constraints are true and core constraints are false.
// issue: what if viable(v) is empty? then we only have cjust constraints and none of them is evaluable (at least not immediately because no value is set for this variable.)
// => think about what we want to do in this case (choose a value and evaluate? try all possible superpositions without caring about the value of the premises?)
// the last value_resolution method can then be the one that adds the cjusts and calls saturation and more general VE.
// No value resolution method was successful => fall back to saturation and variable elimination
for (auto c : cjust_v)
insert(c);
// Variable elimination
while (true) { // TODO: limit?
// TODO: maybe we shouldn't try to split up VE/Saturation in the implementation.
// it might be better to just have more general "core inferences" that may combine elimination/saturation steps that fit together...
// or even keep the whole "value resolution + VE/Saturation" as a single step. we might want to know which constraints come from the current cjusts?
// TODO: as a last resort, substitute v by m_value[v]?
if (!try_saturate(v))
break;
if (try_eliminate(v))
return true;
}
return false;
}
bool conflict_core::try_eliminate(pvar v) {
// TODO: could be tracked incrementally when constraints are added/removed
vector<signed_constraint> v_constraints;