z3-z3-4.13.0.src.sat.sat_clause.cpp Maven / Gradle / Ivy
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/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
sat_clause.cpp
Abstract:
Clauses
Author:
Leonardo de Moura (leonardo) 2011-05-21.
Revision History:
--*/
#include
#include "sat/sat_clause.h"
#include "util/z3_exception.h"
#include "util/trace.h"
namespace sat {
clause::clause(unsigned id, unsigned sz, literal const * lits, bool learned):
m_id(id),
m_size(sz),
m_capacity(sz),
m_removed(false),
m_learned(learned),
m_used(false),
m_frozen(false),
m_reinit_stack(false),
m_inact_rounds(0),
m_glue(255),
m_psm(255) {
memcpy(m_lits, lits, sizeof(literal) * sz);
mark_strengthened();
SASSERT(check_approx());
}
var_approx_set clause::approx(unsigned num, literal const * lits) {
var_approx_set r;
for (unsigned i = 0; i < num; i++)
r.insert(lits[i].var());
return r;
}
void clause::update_approx() {
m_approx = approx(m_size, m_lits);
}
bool clause::check_approx() const {
var_approx_set curr = m_approx;
(void)curr;
const_cast(this)->update_approx();
SASSERT(may_eq(curr, m_approx));
return true;
}
bool clause::contains(literal l) const {
for (literal l2 : *this)
if (l2 == l)
return true;
return false;
}
bool clause::contains(bool_var v) const {
for (literal l : *this)
if (l.var() == v)
return true;
return false;
}
void clause::elim(literal l) {
unsigned i;
for (i = 0; i < m_size; i++)
if (m_lits[i] == l)
break;
SASSERT(i < m_size);
i++;
for (; i < m_size; i++)
m_lits[i-1] = m_lits[i];
m_lits[m_size-1] = l;
m_size--;
mark_strengthened();
}
void clause::shrink(unsigned num_lits) {
SASSERT(num_lits <= m_size);
if (num_lits < m_size) {
m_size = num_lits;
mark_strengthened();
}
}
void clause::restore(unsigned num_lits) {
SASSERT(num_lits <= m_capacity);
m_size = num_lits;
}
bool clause::satisfied_by(model const & m) const {
for (literal l : *this) {
if (l.sign()) {
if (m[l.var()] == l_false)
return true;
}
else {
if (m[l.var()] == l_true)
return true;
}
}
return false;
}
clause_offset clause::get_new_offset() const {
unsigned o1 = m_lits[0].index();
#if defined(__LP64__) || defined(_WIN64)
if (sizeof(clause_offset) == 8) {
unsigned o2 = m_lits[1].index();
return (clause_offset)o1 + (((clause_offset)o2) << 32);
}
#endif
return (clause_offset)o1;
}
void clause::set_new_offset(clause_offset offset) {
m_lits[0] = to_literal(static_cast(offset));
#if defined(__LP64__) || defined(_WIN64)
if (sizeof(offset) == 8) {
m_lits[1] = to_literal(static_cast(offset >> 32));
}
#endif
}
void tmp_clause::set(unsigned num_lits, literal const * lits, bool learned) {
if (m_clause && m_clause->m_capacity < num_lits) {
dealloc_svect(m_clause);
m_clause = nullptr;
}
if (!m_clause) {
void * mem = alloc_svect(char, clause::get_obj_size(num_lits));
m_clause = new (mem) clause(UINT_MAX, num_lits, lits, learned);
}
else {
SASSERT(m_clause->m_id == UINT_MAX);
m_clause->m_size = num_lits;
m_clause->m_learned = learned;
memcpy(m_clause->m_lits, lits, sizeof(literal) * num_lits);
}
SASSERT(m_clause->m_size <= m_clause->m_capacity);
for (unsigned i = 0; i < num_lits; i++) {
SASSERT((*m_clause)[i] == lits[i]);
}
}
clause_allocator::clause_allocator():
m_allocator("clause-allocator") {
}
void clause_allocator::finalize() {
m_allocator.reset();
}
clause * clause_allocator::get_clause(clause_offset cls_off) const {
SASSERT(cls_off == reinterpret_cast(reinterpret_cast(cls_off)));
return reinterpret_cast(cls_off);
}
clause_offset clause_allocator::get_offset(clause const * cls) const {
SASSERT(cls == reinterpret_cast(reinterpret_cast(cls)));
return reinterpret_cast(cls);
}
clause * clause_allocator::mk_clause(unsigned num_lits, literal const * lits, bool learned) {
size_t size = clause::get_obj_size(num_lits);
void * mem = m_allocator.allocate(size);
clause * cls = new (mem) clause(m_id_gen.mk(), num_lits, lits, learned);
TRACE("sat_clause", tout << "alloc: " << cls->id() << " " << *cls << " " << (learned?"l":"a") << "\n";);
SASSERT(!learned || cls->is_learned());
return cls;
}
clause * clause_allocator::copy_clause(clause const& other) {
size_t size = clause::get_obj_size(other.size());
void * mem = m_allocator.allocate(size);
clause * cls = new (mem) clause(m_id_gen.mk(), other.size(), other.m_lits, other.is_learned());
cls->m_reinit_stack = other.on_reinit_stack();
cls->m_glue = other.glue();
cls->m_psm = other.psm();
cls->m_frozen = other.frozen();
cls->m_approx = other.approx();
return cls;
}
void clause_allocator::del_clause(clause * cls) {
TRACE("sat_clause", tout << "delete: " << cls->id() << " " << *cls << "\n";);
m_id_gen.recycle(cls->id());
size_t size = clause::get_obj_size(cls->m_capacity);
cls->~clause();
m_allocator.deallocate(size, cls);
}
std::ostream & operator<<(std::ostream & out, clause const & c) {
out << "(";
for (unsigned i = 0; i < c.size(); i++) {
if (i > 0) out << " ";
out << c[i];
}
out << ")";
if (c.was_removed()) out << "x";
if (c.strengthened()) out << "+";
if (c.is_learned()) out << "*";
return out;
}
std::ostream & operator<<(std::ostream & out, clause_vector const & cs) {
for (clause *cp : cs) {
out << *cp << "\n";
}
return out;
}
bool clause_wrapper::contains(literal l) const {
unsigned sz = size();
for (unsigned i = 0; i < sz; i++)
if (operator[](i) == l)
return true;
return false;
}
bool clause_wrapper::contains(bool_var v) const {
unsigned sz = size();
for (unsigned i = 0; i < sz; i++)
if (operator[](i).var() == v)
return true;
return false;
}
std::ostream & operator<<(std::ostream & out, clause_wrapper const & c) {
if (c.is_binary()) {
out << "(" << c[0] << " " << c[1] << ")";
}
else {
out << c.get_clause()->id() << ": " << *c.get_clause();
}
return out;
}
};