mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-08-25 20:46:01 +00:00
Code Activity

Polysat: fixes in solver, forbidden intervals for eq_constraint (#5240)

Browse source 
* Rename to neg_cond

* Add some logging utilities

* Implement case of forbidden interval covering the whole domain

* Implement diseq_narrow

* Do not activate constraint if we are in a conflict state

* comments

* Assert that lemma isn't undefined

* Update revert_decision to work in the case where narrowing causes propagation

* Fix case of non-disjunctive lemma from forbidden intervals

* Conflict should not leak outside user scope

* Add guard to decide(), some notes

* Add test case

* Add constraints to watchlist of unassigned variable during propagation

* Move common propagation functionality into base class

* Combine eq/diseq narrow

* Compute forbidden interval for equality constraints by considering them as p <=u 0 (or p >u 0 for disequalities)
This commit is contained in:
Jakob Rath 2021-05-03 18:30:17 +02:00 • committed by GitHub
parent 04876ba8b7
commit f7e476a4a0
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
15 changed files with 350 additions and 130 deletions
Download patch file Download diff file Expand all files Collapse all files

23
src/math/polysat/ule_constraint.cpp
View file

@ -22,30 +22,12 @@ namespace polysat {
return out << m_lhs << (sign() == pos_t ? " <=u " : " >u ") << m_rhs << " [" << m_status << "]";
}
bool ule_constraint::propagate(solver& s, pvar v) {
LOG_H3("Propagate " << s.m_vars[v] << " in " << *this);
SASSERT(!vars().empty());
unsigned idx = 0;
if (vars()[idx] != v)
idx = 1;
SASSERT(v == vars()[idx]);
// find other watch variable.
for (unsigned i = vars().size(); i-- > 2; ) {
if (!s.is_assigned(vars()[i])) {
std::swap(vars()[idx], vars()[i]);
return true;
}
}
narrow(s);
return false;
}
constraint* ule_constraint::resolve(solver& s, pvar v) {
return nullptr;
}
void ule_constraint::narrow(solver& s) {
SASSERT(!is_undef());
LOG("Assignment: " << s.m_search);
auto p = lhs().subst_val(s.m_search);
LOG("Substituted LHS: " << lhs() << " := " << p);
@ -136,9 +118,6 @@ namespace polysat {
return p.is_val() && q.is_val() && p.val() > q.val();
}
/**
* Precondition: all variables other than v are assigned.
*/
bool ule_constraint::forbidden_interval(solver& s, pvar v, eval_interval& i, constraint*& neg_condition)
{
SASSERT(!is_undef());