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remove dual solver approach

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
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Nikolaj Bjorner 2022-01-03 14:08:01 -08:00
parent 1f964eea90
commit 8e3185ffe3
13 changed files with 44 additions and 537 deletions
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208
src/sat/smt/euf_relevancy.cpp
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@ -1,208 +0,0 @@
/*++
Copyright (c) 2020 Microsoft Corporation
Module Name:
euf_relevancy.cpp
Abstract:
Features for relevancy tracking.
A reduced (minimal) implicant is extracted by running a dual solver.
Then the literals in the implicant are used as a basis for marking
subterms relevant.
Author:
Nikolaj Bjorner (nbjorner) 2020-09-22
--*/
#include "sat/smt/euf_solver.h"
namespace euf {
void solver::mark_relevant(sat::literal lit) {
if (m_relevancy.enabled()) {
m_relevancy.mark_relevant(lit);
return;
}
if (!relevancy_enabled())
return;
for (; m_auto_relevant_scopes > 0; --m_auto_relevant_scopes)
m_auto_relevant_lim.push_back(m_auto_relevant.size());
expr* e = bool_var2expr(lit.var());
m_auto_relevant.push_back(e);
}
void solver::pop_relevant(unsigned n) {
if (m_relevancy.enabled()) {
m_relevancy.pop(n);
return;
}
if (m_auto_relevant_scopes >= n) {
m_auto_relevant_scopes -= n;
return;
}
n -= m_auto_relevant_scopes;
m_auto_relevant_scopes = 0;
unsigned top = m_auto_relevant_lim.size() - n;
unsigned lim = m_auto_relevant_lim[top];
m_auto_relevant_lim.shrink(top);
m_auto_relevant.shrink(lim);
}
void solver::push_relevant() {
if (m_relevancy.enabled()) {
m_relevancy.push();
return;
}
++m_auto_relevant_scopes;
}
bool solver::is_relevant(enode* n) const {
if (m_relevancy.enabled())
return m_relevancy.is_relevant(n);
return m_relevant_expr_ids.get(n->get_expr_id(), true);
}
bool solver::is_relevant(bool_var v) const {
if (m_relevancy.enabled())
return m_relevancy.is_relevant(v);
auto* e = bool_var2enode(v);
return !e || is_relevant(e);
}
void solver::ensure_dual_solver() {
if (m_relevancy.enabled())
return;
if (m_dual_solver)
return;
m_dual_solver = alloc(sat::dual_solver, s(), s().rlimit());
for (unsigned i = s().num_user_scopes(); i-- > 0; )
m_dual_solver->push();
}
/**
* Add a root clause. Root clauses must all be satisfied by the
* final assignment. If a clause is added above search level it
* is subject to removal on backtracking. These clauses are therefore
* not tracked.
*/
void solver::add_root(unsigned n, sat::literal const* lits) {
if (m_relevancy.enabled()) {
m_relevancy.add_root(n, lits);
return;
}
if (!relevancy_enabled())
return;
ensure_dual_solver();
m_dual_solver->add_root(n, lits);
}
void solver::add_aux(unsigned n, sat::literal const* lits) {
if (m_relevancy.enabled()) {
m_relevancy.add_def(n, lits);
return;
}
if (!relevancy_enabled())
return;
ensure_dual_solver();
m_dual_solver->add_aux(n, lits);
}
void solver::track_relevancy(sat::bool_var v) {
if (m_relevancy.enabled())
return;
ensure_dual_solver();
m_dual_solver->track_relevancy(v);
}
bool solver::init_relevancy() {
if (m_relevancy.enabled())
return true;
m_relevant_expr_ids.reset();
if (!relevancy_enabled())
return true;
if (!m_dual_solver)
return true;
if (!(*m_dual_solver)())
return false;
init_relevant_expr_ids();
for (auto lit : m_dual_solver->core())
push_relevant(lit.var());
relevant_subterms();
return true;
}
void solver::push_relevant(sat::bool_var v) {
SASSERT(!m_relevancy.enabled());
expr* e = m_bool_var2expr.get(v, nullptr);
if (e)
m_relevant_todo.push_back(e);
}
bool solver::is_propagated(sat::literal lit) {
SASSERT(!m_relevancy.enabled());
return s().value(lit) == l_true && !s().get_justification(lit.var()).is_none();
}
void solver::init_relevant_expr_ids() {
SASSERT(!m_relevancy.enabled());
unsigned max_id = 0;
for (enode* n : m_egraph.nodes())
max_id = std::max(max_id, n->get_expr_id());
m_relevant_expr_ids.resize(max_id + 1, false);
m_relevant_todo.reset();
m_relevant_todo.append(m_auto_relevant);
}
void solver::relevant_subterms() {
SASSERT(!m_relevancy.enabled());
ptr_vector<expr>& todo = m_relevant_todo;
bool_vector& visited = m_relevant_visited;
for (unsigned i = 0; i < todo.size(); ++i) {
expr* e = todo[i];
if (visited.get(e->get_id(), false))
continue;
visited.setx(e->get_id(), true, false);
if (si.is_bool_op(e))
continue;
else
m_relevant_expr_ids.setx(e->get_id(), true, false);
if (!is_app(e))
continue;
expr* c = nullptr, *th = nullptr, *el = nullptr;
if (m.is_ite(e, c, th, el) && get_enode(c)) {
sat::literal lit = expr2literal(c);
todo.push_back(c);
switch (s().value(lit)) {
case l_true:
todo.push_back(th);
break;
case l_false:
todo.push_back(el);
break;
default:
todo.push_back(th);
todo.push_back(el);
break;
}
continue;
}
for (expr* arg : *to_app(e))
todo.push_back(arg);
}
for (auto * e : todo)
visited[e->get_id()] = false;
TRACE("euf",
for (enode* n : m_egraph.nodes())
if (is_relevant(n))
tout << "relevant " << n->get_expr_id() << " [r" << n->get_root_id() << "]: " << mk_bounded_pp(n->get_expr(), m) << "\n";);
}
}