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fixes

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This commit is contained in:
Nikolaj Bjorner 2021-09-16 10:10:50 +01:00
parent 689c5b4e12
commit c25fd71bf4
5 changed files with 44 additions and 35 deletions
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5
src/math/polysat/boolean.cpp
View file

@ -11,6 +11,7 @@ Author:
--*/
#include "math/polysat/boolean.h"
#include "math/polysat/clause.h"
#include "math/polysat/log.h"
namespace polysat {
@ -69,10 +70,10 @@ namespace polysat {
std::ostream& bool_var_manager::display(std::ostream& out) const {
for (sat::bool_var v = 0; v < size(); ++v) {
sat::literal lit{v};
sat::literal lit(v);
if (value(lit) == l_true)
out << " " << lit;
if (value(lit) == l_false)
else if (value(lit) == l_false)
out << " " << ~lit;
}
return out;

3
src/math/polysat/conflict_core.cpp
View file

@ -103,7 +103,7 @@ namespace polysat {
}
void conflict_core::insert(signed_constraint c) {
LOG("inserting: " << c);
LOG("inserting: " << c << " " << c.is_always_true() << " " << c->is_marked() << " " << c->has_bvar());
// Skip trivial constraints
// (e.g., constant ones such as "4 > 1"... only true ones should appear, otherwise the lemma would be a tautology)
if (c.is_always_true())
@ -164,6 +164,7 @@ namespace polysat {
remove_literal(sat::literal(var));
if (core_has_neg)
remove_literal(~sat::literal(var));
unset_bmark(var);
for (sat::literal lit : cl)
if (lit.var() != var)

19
src/math/polysat/explain.cpp
View file

@ -78,17 +78,16 @@ namespace polysat {
signed_constraint c = find_replacement(c2, v, core);
if (!c)
continue;
if (!c->contains_var(v)) {
core.keep(c); // adds propagation of c to the search stack
// NOTE: more variables than just 'v' might have been removed here (see polysat::test_p3).
// c alone (+ variables) is now enough to represent the conflict.
core.reset();
core.set(c);
return l_true;
}
else
if (c->contains_var(v))
return l_undef;
if (!c->has_bvar() || l_undef == c.bvalue(s()))
core.keep(c); // adds propagation of c to the search stack
// NOTE: more variables than just 'v' might have been removed here (see polysat::test_p3).
// c alone (+ variables) is now enough to represent the conflict.
core.reset();
core.set(c);
return l_true;
}
return l_false;
}

50
src/math/polysat/solver.cpp
View file

@ -508,12 +508,12 @@ namespace polysat {
}
/** Conflict resolution case where boolean literal 'lit' is on top of the stack */
void solver::resolve_bool(sat::literal lit) {
LOG_H3("resolve_bool: " << lit);
void solver::resolve_bool(sat::literal lit) {
sat::bool_var const var = lit.var();
SASSERT(m_bvars.is_propagation(var));
// NOTE: boolean resolution should work normally even in bailout mode.
clause* other = m_bvars.reason(var);
LOG_H3("resolve_bool: " << lit << " " << *other);
m_conflict.resolve(m_constraints, var, *other);
}
@ -543,12 +543,11 @@ namespace polysat {
SASSERT(lemma->size() > 0);
lemma->set_justified_var(v);
add_lemma(lemma);
sat::literal lit = decide_bool(*lemma);
SASSERT(lit != sat::null_literal);
decide_bool(*lemma);
}
// Guess a literal from the given clause; returns the guessed constraint
sat::literal solver::decide_bool(clause& lemma) {
void solver::decide_bool(clause& lemma) {
LOG_H3("Guessing literal in lemma: " << lemma);
IF_LOGGING(m_viable.log());
LOG("Boolean assignment: " << m_bvars);
@ -574,20 +573,21 @@ namespace polysat {
}
}
LOG_V("num_choices: " << num_choices);
if (choice == sat::null_literal) {
// This case may happen when all undefined literals are false under the current variable assignment.
// TODO: The question is whether such lemmas should be generated? Check test_monot() for such a case.
for (auto lit : lemma)
set_conflict(~m_constraints.lookup(lit));
return;
}
signed_constraint c = m_constraints.lookup(choice);
push_cjust(lemma.justified_var(), c);
if (num_choices == 0) {
// This case may happen when all undefined literals are false under the current variable assignment.
// TODO: The question is whether such lemmas should be generated? Check test_monot() for such a case.
// set_conflict(lemma);
NOT_IMPLEMENTED_YET();
} else if (num_choices == 1)
if (num_choices == 1)
propagate_bool(choice, &lemma);
else
decide_bool(choice, lemma);
return choice;
}
/**
@ -603,7 +603,7 @@ namespace polysat {
m_conflict.reset();
backjump(m_justification[v].level() - 1);
// The justification for this restriction is the guessed constraint from the lemma.
// cjust[v] will be updated accordingly by decide_bool.
m_viable.add_non_viable(v, val);
@ -805,15 +805,23 @@ namespace polysat {
std::ostream& solver::display(std::ostream& out) const {
out << "Assignment:\n";
for (auto [v, val] : assignment()) {
auto j = m_justification[v];
out << "\t" << assignment_pp(*this, v, val) << " @" << j.level();
if (j.is_propagation())
out << " " << m_cjust[v];
out << "\n";
// out << m_viable[v] << "\n";
for (auto item : m_search) {
if (item.is_assignment()) {
pvar v = item.var();
auto j = m_justification[v];
out << "\t" << assignment_pp(*this, v, get_value(v)) << " @" << j.level();
if (j.is_propagation())
out << " " << m_cjust[v];
out << "\n";
}
else {
sat::bool_var v = item.lit().var();
out << "\t" << item.lit() << " @" << m_bvars.level(v);
if (m_bvars.reason(v))
out << " " << *m_bvars.reason(v);
out << "\n";
}
}
out << "Boolean assignment:\n\t" << m_bvars << "\n";
out << "Constraints:\n";
for (auto c : m_constraints)
out << "\t" << *c << "\n";

2
src/math/polysat/solver.h
View file

@ -153,7 +153,7 @@ namespace polysat {
void assign_bool(unsigned level, sat::literal lit, clause* reason, clause* lemma);
void activate_constraint(signed_constraint c);
void deactivate_constraint(signed_constraint c);
sat::literal decide_bool(clause& lemma);
void decide_bool(clause& lemma);
void decide_bool(sat::literal lit, clause& lemma);
void propagate_bool(sat::literal lit, clause* reason);
void propagate_bool_at(unsigned level, sat::literal lit, clause* reason);