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updates

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2017-02-27 23:19:58 -08:00
parent c205b59a21
commit 31c68b6e23
6 changed files with 170 additions and 97 deletions
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79
src/sat/sat_local_search.h
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@ -21,30 +21,29 @@
#include "vector.h"
#include "sat_types.h"
#include "rlimit.h"
namespace sat {
class parallel;
class local_search_config {
unsigned m_seed;
unsigned m_cutoff_time;
unsigned m_strategy_id;
int m_best_known_value;
public:
local_search_config()
{
m_seed = 0;
m_cutoff_time = 1;
m_strategy_id = 0;
m_best_known_value = INT_MAX;
}
unsigned seed() const { return m_seed; }
unsigned cutoff_time() const { return m_cutoff_time; }
unsigned strategy_id() const { return m_strategy_id; }
unsigned best_known_value() const { return m_best_known_value; }
void set_seed(unsigned s) { m_seed = s; }
void set_cutoff_time(unsigned t) { m_cutoff_time = t; }
void set_strategy_id(unsigned i) { m_strategy_id = i; }
void set_best_known_value(unsigned v) { m_best_known_value = v; }
};
@ -58,21 +57,8 @@ namespace sat {
struct ob_term {
bool_var var_id; // variable id, begin with 1
int coefficient; // non-zero integer
ob_term(bool_var v, int c): var_id(v), coefficient(c) {}
};
// data structure for a term in constraint
struct term {
bool_var var_id; // variable id, begin with 1
bool sense; // 1 for positive, 0 for negative
//int coefficient; // all constraints are cardinality: coefficient=1
};
// objective function: maximize
svector<ob_term> ob_constraint; // the objective function *constraint*, sorted in decending order
// information about the variable
int_vector coefficient_in_ob_constraint; // initialized to be 0
struct var_info {
bool m_conf_change; // whether its configure changes since its last flip
@ -92,6 +78,24 @@ namespace sat {
{}
};
struct constraint {
unsigned m_k;
int m_slack;
literal_vector m_literals;
constraint(unsigned k) : m_k(k), m_slack(0) {}
unsigned size() const { return m_literals.size(); }
literal const& operator[](unsigned idx) const { return m_literals[idx]; }
};
local_search_config m_config;
// objective function: maximize
svector<ob_term> ob_constraint; // the objective function *constraint*, sorted in decending order
// information about the variable
int_vector coefficient_in_ob_constraint; // var! initialized to be 0
vector<var_info> m_vars;
inline int score(bool_var v) const { return m_vars[v].m_score; }
@ -107,23 +111,14 @@ namespace sat {
inline int time_stamp(bool_var v) const { return m_vars[v].m_time_stamp; }
inline int cscc(bool_var v) const { return m_vars[v].m_cscc; }
inline void inc_cscc(bool_var v) { m_vars[v].m_cscc++; }
unsigned num_vars() const { return m_vars.size() - 1; } // var index from 1 to num_vars
/* TBD: other scores */
struct constraint {
unsigned m_k;
int m_slack;
literal_vector m_literals;
constraint(unsigned k) : m_k(k), m_slack(0) {}
unsigned size() const { return m_literals.size(); }
literal const& operator[](unsigned idx) const { return m_literals[idx]; }
};
vector<constraint> m_constraints;
inline bool is_pos(literal t) const { return !t.sign(); }
inline bool is_true(bool_var v) const { return cur_solution[v]; }
inline bool is_true(literal l) const { return cur_solution[l.var()] != l.sign(); }
inline bool is_false(literal l) const { return cur_solution[l.var()] == l.sign(); }
@ -141,22 +136,21 @@ namespace sat {
int_vector goodvar_stack;
// information about solution
bool_vector cur_solution; // the current solution
bool_vector cur_solution; // !var: the current solution
int objective_value; // the objective function value corresponds to the current solution
bool_vector best_solution; // the best solution so far
bool_vector best_solution; // !var: the best solution so far
int best_objective_value = -1; // the objective value corresponds to the best solution so far
// for non-known instance, set as maximal
int best_known_value = INT_MAX; // best known value for this instance
// cutoff
int cutoff_time = 1; // seconds
unsigned max_steps = 2000000000; // < 2147483647
clock_t start, stop;
double best_time;
// for tuning
int s_id = 0; // strategy id
reslimit m_limit;
random_gen m_rand;
parallel* m_par;
void init();
void reinit();
@ -220,24 +214,31 @@ namespace sat {
m_unsat_stack.pop_back();
}
public:
local_search(solver& s);
reslimit& rlimit() { return m_limit; }
~local_search();
void add_soft(int l, int weight);
void add_soft(bool_var v, int weight);
void add_cardinality(unsigned sz, literal const* c, unsigned k);
lbool operator()();
lbool check();
lbool check(unsigned sz, literal const* assumptions) { return l_undef; } // TBD
lbool check(unsigned sz, literal const* assumptions);
void cancel() {} // TBD
lbool check(parallel& p);
local_search_config& config() { return m_config; }
local_search_config m_config;
unsigned num_vars() const { return m_vars.size() - 1; } // var index from 1 to num_vars
void set_phase(bool_var v, bool f) {}
bool get_phase(bool_var v) const { return is_true(v); }
};
}