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conflict logging

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This commit is contained in:
Jakob Rath 2022-04-12 16:06:20 +02:00
parent 00fa4b3320
commit 9fa5096776
11 changed files with 210 additions and 26 deletions
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142
src/math/polysat/conflict.cpp
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@ -31,18 +31,119 @@ Notes:
#include "math/polysat/saturation.h"
#include "math/polysat/variable_elimination.h"
#include <algorithm>
#include <fstream>
namespace polysat {
conflict::conflict(solver& s):s(s) {
class inference_logger {
uint_set m_used_constraints;
uint_set m_used_vars;
scoped_ptr<std::ostream> m_out = nullptr;
unsigned m_conflicts = 0;
std::ostream& out() {
SASSERT(m_out);
return *m_out;
}
std::ostream& out_indent() { return out() << " "; }
std::string hline() const { return std::string(70, '-'); }
public:
void begin_conflict() {
m_used_constraints.reset();
m_used_vars.reset();
if (!m_out)
m_out = alloc(std::ofstream, "conflicts.txt");
else
out() << "\n\n\n\n\n" << hline() << "\n" << hline() << "\n" << hline() << "\n\n\n\n\n";
out() << "CONFLICT #" << ++m_conflicts << "\n";
}
void log_inference(conflict const& core, inference const* inf) {
out() << hline() << "\n";
if (inf)
out() << *inf << "\n";
if (core.conflict_var() != null_var) {
out_indent() << "Conflict var: " << core.conflict_var() << "\n";
m_used_vars.insert(core.conflict_var());
}
for (auto const& c : core) {
out_indent() << c.blit() << ": " << c << '\n';
m_used_constraints.insert(c.blit().index());
}
for (auto v : core.vars()) {
out_indent() << "v" << v << "\n";
m_used_vars.insert(v);
}
for (auto v : core.bail_vars()) {
out_indent() << "v" << v << " (bail)\n";
m_used_vars.insert(v);
}
out().flush();
}
void log_lemma(clause_builder const& cb) {
out() << hline() << "\nLemma:";
for (auto const& lit : cb)
out() << " " << lit;
out() << "\n";
out().flush();
}
void log_gamma(search_state const& m_search) {
out() << "\n" << hline() << "\n\n";
out() << "Search state (part):\n";
for (auto const& item : m_search)
if (is_relevant(item))
out_indent() << search_item_pp(m_search, item, true) << "\n";
// TODO: log viable
out().flush();
}
bool is_relevant(search_item const& item) const {
switch (item.kind()) {
case search_item_k::assignment:
return m_used_vars.contains(item.var());
case search_item_k::boolean:
return m_used_constraints.contains(item.lit().index());
}
UNREACHABLE();
return false;
}
};
conflict::conflict(solver& s): s(s) {
ex_engines.push_back(alloc(ex_polynomial_superposition, s));
ex_engines.push_back(alloc(eq_explain, s));
ve_engines.push_back(alloc(ve_reduction));
inf_engines.push_back(alloc(inf_saturate, s));
// TODO: how to set this on the CLI? "polysat.log_conflicts=true" doesn't seem to work although z3 accepts it
if (true || s.get_config().m_log_conflicts)
m_logger = alloc(inference_logger);
}
conflict::~conflict() {}
void conflict::begin_conflict() {
if (m_logger) {
m_logger->begin_conflict();
// log initial conflict state
m_logger->log_inference(*this, nullptr);
}
}
void conflict::log_inference(inference const& inf) {
if (m_logger)
m_logger->log_inference(*this, &inf);
}
void conflict::log_gamma() {
if (m_logger)
m_logger->log_gamma(s.m_search);
}
constraint_manager& conflict::cm() const { return s.m_constraints; }
std::ostream& conflict::display(std::ostream& out) const {
@ -176,6 +277,7 @@ namespace polysat {
* NOTE: maybe we should skip intermediate steps and just collect the leaf premises for c?
* Ensure that c is assigned and justified
*/
// TODO: rename this; it pushes onto \Gamma and doesn't insert into the core
void conflict::insert(signed_constraint c, vector<signed_constraint> const& premises) {
// keep(c);
clause_builder c_lemma(s);
@ -217,6 +319,15 @@ namespace polysat {
s.m_stats.m_num_bailouts++;
}
struct inference_resolve : public inference {
sat::literal m_lit;
clause const& m_clause;
inference_resolve(sat::literal lit, clause const& cl) : m_lit(lit), m_clause(cl) {}
std::ostream& display(std::ostream& out) const override {
return out << "Resolve upon " << m_lit << " with " << m_clause;
}
};
void conflict::resolve(sat::literal lit, clause const& cl) {
// Note: core: x, y, z; corresponds to clause ~x \/ ~y \/ ~z
// clause: x \/ u \/ v
@ -233,8 +344,22 @@ namespace polysat {
for (sat::literal lit2 : cl)
if (lit2 != lit)
insert(s.lit2cnstr(~lit2));
log_inference(inference_resolve(lit, cl));
}
struct inference_resolve_with_assignment : public inference {
solver& s;
sat::literal lit;
signed_constraint c;
inference_resolve_with_assignment(solver& s, sat::literal lit, signed_constraint c) : s(s), lit(lit), c(c) {}
std::ostream& display(std::ostream& out) const override {
out << "Resolve upon " << lit << " with assignment:";
for (pvar v : c->vars())
out << " " << assignment_pp(s, v, s.get_value(v), true);
return out;
}
};
void conflict::resolve_with_assignment(sat::literal lit, unsigned lvl) {
// The reason for lit is conceptually:
// x1 = v1 /\ ... /\ xn = vn ==> lit
@ -259,6 +384,7 @@ namespace polysat {
m_vars.insert(v);
}
}
log_inference(inference_resolve_with_assignment(s, lit, c));
}
clause_builder conflict::build_lemma() {
@ -280,6 +406,9 @@ namespace polysat {
}
s.decay_activity();
if (m_logger)
m_logger->log_lemma(lemma);
return lemma;
}
@ -309,10 +438,20 @@ namespace polysat {
m_vars.reset();
for (auto const& [v, val] : a)
m_vars.insert(v);
log_inference("minimize vars");
LOG("reduced " << m_vars);
}
struct inference_resolve_value : public inference {
solver& s;
pvar v;
inference_resolve_value(solver& s, pvar v) : s(s), v(v) {}
std::ostream& display(std::ostream& out) const override {
return out << "Value resolution with " << assignment_pp(s, v, s.get_value(v), true);
}
};
bool conflict::resolve_value(pvar v) {
// NOTE:
// In the "standard" case where "v = val" is on the stack:
@ -353,6 +492,7 @@ namespace polysat {
bailout:
if (s.is_assigned(v) && j.is_decision())
m_vars.insert(v);
log_inference(inference_resolve_value(s, v));
return false;
}