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parity debugging

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This commit is contained in:
Jakob Rath 2022-12-23 11:42:45 +01:00
parent 1434c1117c
commit 68b74ca6a7
3 changed files with 38 additions and 12 deletions
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21
src/math/polysat/saturation.cpp
View file

@ -810,10 +810,17 @@ namespace polysat {
unsigned offset = coeff.trailing_zeros();
verbose_stream() << "COEFF " << coeff << "\n";
#endif
#if 0
unsigned j = 0;
while (j < N && is_forced_true(s.parity(p, j)))
while (j < N && is_forced_true(s.parity(p, j + 1)))
++j;
return j;
#else
for (unsigned j = N; j > 0; --j)
if (is_forced_true(s.parity(p, j)))
return j;
return 0;
#endif
}
unsigned saturation::max_parity(pdd const& p) {
@ -826,8 +833,8 @@ namespace polysat {
// TBD: factor p
for (unsigned j = 0; j < N; ++j)
if (is_forced_false(s.parity(p, j)))
return j + 1;
if (is_forced_true(s.parity_at_most(p, j)))
return j;
return N;
}
@ -852,10 +859,10 @@ namespace polysat {
auto propagate1 = [&](signed_constraint premise, signed_constraint conseq) {
if (is_forced_false(premise))
return false;
IF_VERBOSE(1, verbose_stream() << "propagate " << axb_l_y << " " << premise << " => " << conseq << "\n");
m_lemma.reset();
m_lemma.insert_eval(~s.eq(y));
m_lemma.insert_eval(~premise);
IF_VERBOSE(1, verbose_stream() << "propagate " << axb_l_y << " " << premise << " => " << conseq << "\n");
return propagate(x, core, axb_l_y, conseq);
};
@ -864,11 +871,11 @@ namespace polysat {
return false;
if (is_forced_false(premise2))
return false;
IF_VERBOSE(1, verbose_stream() << "propagate " << axb_l_y << " " << premise1 << " " << premise2 << " => " << conseq << "\n");
m_lemma.reset();
m_lemma.insert_eval(~s.eq(y));
m_lemma.insert_eval(~premise1);
m_lemma.insert_eval(~premise2);
IF_VERBOSE(1, verbose_stream() << "propagate " << axb_l_y << " " << premise1 << " " << premise2 << " => " << conseq << "\n");
return propagate(x, core, axb_l_y, conseq);
};
@ -889,8 +896,8 @@ namespace polysat {
return false;
auto at_most = [&](pdd const& p, unsigned k) {
VERIFY(k != N);
return ~s.parity(p, k + 1);
VERIFY(k < N);
return s.parity_at_most(p, k);
};
auto at_least = [&](pdd const& p, unsigned k) {

1
src/math/polysat/solver.cpp
View file

@ -1059,6 +1059,7 @@ namespace polysat {
void solver::assign_eval(sat::literal lit) {
signed_constraint const c = lit2cnstr(lit);
LOG_V(10, "Evaluate: " << lit_pp(*this ,lit));
SASSERT(c.is_currently_true(*this));
unsigned level = 0;
// NOTE: constraint may be evaluated even if some variables are still unassigned (e.g., 0*x doesn't depend on x).

28
src/math/polysat/solver.h
View file

@ -418,15 +418,33 @@ namespace polysat {
signed_constraint eq(pdd const& p, unsigned q) { return eq(p - q); }
signed_constraint odd(pdd const& p) { return ~even(p); }
signed_constraint even(pdd const& p) { return parity(p, 1); }
/** parity(p) >= k (<=> p * 2^(K-k) == 0) */
signed_constraint parity(pdd const& p, unsigned k) {
/** parity(p) >= k */
signed_constraint parity(pdd const& p, unsigned k) { // TODO: rename to parity_at_least?
unsigned N = p.manager().power_of_2();
// parity(p) >= k
// <=> p * 2^(N - k) == 0
if (k >= N)
return eq(p);
else if (k == 0)
return odd(p);
else if (k == 0) {
// parity(p) >= 0 is a tautology
verbose_stream() << "REDUNDANT parity constraint: parity(" << p << ", " << k << ")\n";
return eq(p.manager().zero());
}
else
return eq(p*rational::power_of_two(N - k));
return eq(p * rational::power_of_two(N - k));
}
/** parity(p) <= k */
signed_constraint parity_at_most(pdd const& p, unsigned k) {
unsigned N = p.manager().power_of_2();
// parity(p) <= k
// <=> ~(parity(p) >= k+1)
if (k >= N) {
// parity(p) <= N is a tautology
verbose_stream() << "REDUNDANT parity constraint: parity(" << p << ", " << k << ")\n";
return eq(p.manager().zero());
}
else
return ~parity(p, k + 1);
}
signed_constraint diseq(pdd const& p, rational const& q) { return diseq(p - q); }
signed_constraint diseq(pdd const& p, unsigned q) { return diseq(p - q); }