mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-08-26 13:06:05 +00:00
Code Activity

Merge branch 'polysat' of https://github.com/Z3Prover/z3 into polysat

Browse source
This commit is contained in:
Clemens Eisenhofer 2022-12-07 16:35:42 +01:00
commit 47cb83f578
34 changed files with 1540 additions and 888 deletions
Download patch file Download diff file Expand all files Collapse all files

21
src/math/polysat/constraint_manager.cpp
View file

@ -275,6 +275,7 @@ namespace polysat {
return ult(a + shift, b + shift);
}
/** unsigned quotient/remainder */
std::pair<pdd, pdd> constraint_manager::quot_rem(pdd const& a, pdd const& b) {
auto& m = a.manager();
unsigned sz = m.power_of_2();
@ -282,6 +283,9 @@ namespace polysat {
// By SMT-LIB specification, b = 0 ==> q = -1, r = a.
return {m.mk_val(m.max_value()), a};
}
if (b.is_one()) {
return {a, m.zero()};
}
if (a.is_val() && b.is_val()) {
rational const av = a.val();
rational const bv = b.val();
@ -296,7 +300,14 @@ namespace polysat {
SASSERT(r.val() < b.val());
return {std::move(q), std::move(r)};
}
constraint_dedup::quot_rem_args args({ a, b });
#if 0
unsigned pow;
if (b.is_val() && b.val().is_power_of_two(pow)) {
// TODO: q = a >> b.val()
// r = 0 \circ a[pow:] ???
}
#endif
constraint_dedup::quot_rem_args args({a, b});
auto it = m_dedup.quot_rem_expr.find_iterator(args);
if (it != m_dedup.quot_rem_expr.end())
return { m.mk_var(it->m_value.first), m.mk_var(it->m_value.second) };
@ -311,17 +322,17 @@ namespace polysat {
// addition does not overflow in (b*q) + r; for now expressed as: r <= bq+r
// b ≠ 0 ==> r < b
// b = 0 ==> q = -1
s.add_eq(a, b * q + r);
s.add_umul_noovfl(b, q);
s.add_clause(eq(b * q + r - a), false);
s.add_clause(~umul_ovfl(b, q), false);
// r <= b*q+r
// { apply equivalence: p <= q <=> q-p <= -p-1 }
// b*q <= -r-1
s.add_ule(b*q, -r-1);
s.add_clause(ule(b*q, -r-1), false);
#if 0
// b*q <= b*q+r
// { apply equivalence: p <= q <=> q-p <= -p-1 }
// r <= - b*q - 1
s.add_ule(r, -b*q-1); // redundant, but may help propagation
s.add_clause(ule(r, -b*q-1), false); // redundant, but may help propagation
#endif
auto c_eq = eq(b);