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working on pb solver

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2013-11-14 18:04:05 -08:00
parent d8d77d943c
commit 06ae0db116
5 changed files with 144 additions and 48 deletions
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38
src/opt/fu_malik.cpp
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@ -18,6 +18,8 @@ Notes:
--*/
#include "fu_malik.h"
#include "smtlogics/qfbv_tactic.h"
#include "tactic2solver.h"
/**
\brief Fu & Malik procedure for MaxSAT. This procedure is based on
@ -37,17 +39,18 @@ namespace opt {
struct fu_malik::imp {
ast_manager& m;
solver& s;
ref<solver> m_s;
expr_ref_vector m_soft;
expr_ref_vector m_orig_soft;
expr_ref_vector m_aux;
expr_ref_vector m_assignment;
unsigned m_upper_size;
solver& s() { return *m_s; }
imp(ast_manager& m, solver& s, expr_ref_vector const& soft):
m(m),
s(s),
m_s(&s),
m_soft(soft),
m_orig_soft(soft),
m_aux(m),
@ -78,13 +81,13 @@ namespace opt {
for (unsigned i = 0; i < m_soft.size(); ++i) {
assumptions.push_back(m.mk_not(m_aux[i].get()));
}
lbool is_sat = s.check_sat(assumptions.size(), assumptions.c_ptr());
lbool is_sat = s().check_sat(assumptions.size(), assumptions.c_ptr());
if (is_sat != l_false) {
return is_sat;
}
ptr_vector<expr> core;
s.get_unsat_core(core);
s().get_unsat_core(core);
// Update soft-constraints and aux_vars
for (unsigned i = 0; i < m_soft.size(); ++i) {
@ -101,7 +104,7 @@ namespace opt {
m_aux[i] = m.mk_fresh_const("aux", m.mk_bool_sort());
m_soft[i] = m.mk_or(m_soft[i].get(), block_var);
block_vars.push_back(block_var);
s.assert_expr(m.mk_or(m_soft[i].get(), m_aux[i].get()));
s().assert_expr(m.mk_or(m_soft[i].get(), m_aux[i].get()));
}
assert_at_most_one(block_vars);
return l_false;
@ -111,7 +114,7 @@ namespace opt {
expr_ref has_one(m), has_zero(m), at_most_one(m);
mk_at_most_one(block_vars.size(), block_vars.c_ptr(), has_one, has_zero);
at_most_one = m.mk_or(has_one, has_zero);
s.assert_expr(at_most_one);
s().assert_expr(at_most_one);
}
void mk_at_most_one(unsigned n, expr* const * vars, expr_ref& has_one, expr_ref& has_zero) {
@ -129,15 +132,30 @@ namespace opt {
has_zero = m.mk_and(has_zero1, has_zero2);
}
}
void set_solver() {
solver& original_solver = s();
bool all_bv = false;
// retrieve goal from s()
// extract mk_qfbv_probe
// run probe on goals
// if result is "yes", then create teh qfbv_tactic.
if (all_bv) {
tactic* t = mk_qfbv_tactic(m);
m_s = mk_tactic2solver(m, t);
}
}
// TBD: bug when cancel flag is set, fu_malik returns is_sat == l_true instead of l_undef
lbool operator()() {
lbool is_sat = s.check_sat(0,0);
set_solver();
lbool is_sat = s().check_sat(0,0);
if (!m_soft.empty() && is_sat == l_true) {
solver::scoped_push _sp(s);
solver::scoped_push _sp(s());
for (unsigned i = 0; i < m_soft.size(); ++i) {
m_aux.push_back(m.mk_fresh_const("p", m.mk_bool_sort()));
s.assert_expr(m.mk_or(m_soft[i].get(), m_aux[i].get()));
s().assert_expr(m.mk_or(m_soft[i].get(), m_aux[i].get()));
}
lbool is_sat = l_true;
@ -150,7 +168,7 @@ namespace opt {
if (is_sat == l_true) {
// Get a list of satisfying m_soft
model_ref model;
s.get_model(model);
s().get_model(model);
m_assignment.reset();
for (unsigned i = 0; i < m_orig_soft.size(); ++i) {