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wip - local search for euf/arithmetic

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This commit is contained in:
Nikolaj Bjorner 2023-02-11 09:33:35 -08:00
parent 46c8d78ece
commit 7bef2f3e6f
9 changed files with 716 additions and 172 deletions
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113
src/sat/smt/arith_solver.h
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@ -30,6 +30,7 @@ Author:
#include "math/polynomial/algebraic_numbers.h"
#include "math/polynomial/polynomial.h"
#include "sat/smt/sat_th.h"
#include "sat/smt/arith_sls.h"
#include "sat/sat_ddfw.h"
namespace euf {
@ -98,6 +99,7 @@ namespace arith {
class solver : public euf::th_euf_solver {
friend struct arith_proof_hint;
friend class sls;
struct scope {
unsigned m_bounds_lim;
@ -190,116 +192,7 @@ namespace arith {
coeffs().pop_back();
}
};
// local search portion for arithmetic
class sls {
enum class ineq_kind { EQ, LE, LT, NE };
enum class var_kind { INT, REAL };
typedef unsigned var_t;
typedef unsigned atom_t;
struct config {
double cb = 0.0;
unsigned L = 20;
unsigned t = 45;
unsigned max_no_improve = 500000;
double sp = 0.0003;
};
struct stats {
unsigned m_num_flips = 0;
};
// encode args <= bound, args = bound, args < bound
struct ineq {
vector<std::pair<rational, var_t>> m_args;
ineq_kind m_op = ineq_kind::LE;
rational m_bound;
rational m_args_value;
bool is_true() const {
switch (m_op) {
case ineq_kind::LE:
return m_args_value <= m_bound;
case ineq_kind::EQ:
return m_args_value == m_bound;
case ineq_kind::NE:
return m_args_value != m_bound;
default:
return m_args_value < m_bound;
}
}
};
struct var_info {
rational m_value;
rational m_best_value;
var_kind m_kind = var_kind::INT;
vector<std::pair<rational, atom_t>> m_atoms;
};
struct atom_info {
ineq m_ineq;
unsigned m_clause_idx;
bool m_is_bool = false;
bool m_phase = false;
bool m_best_phase = false;
unsigned m_breaks = 0;
};
struct clause {
unsigned m_weight = 1;
rational m_dts = rational::one();
};
solver& s;
ast_manager& m;
sat::ddfw* m_bool_search = nullptr;
unsigned m_max_arith_steps = 0;
unsigned m_best_min_unsat = UINT_MAX;
stats m_stats;
config m_config;
scoped_ptr_vector<atom_info> m_atoms;
vector<var_info> m_vars;
vector<clause> m_clauses;
indexed_uint_set& unsat() { return m_bool_search->unsat_set(); }
unsigned num_clauses() const { return m_bool_search->num_clauses(); }
sat::clause& get_clause(unsigned idx) { return *get_clause_info(idx).m_clause; }
sat::clause const& get_clause(unsigned idx) const { return *get_clause_info(idx).m_clause; }
sat::ddfw::clause_info& get_clause_info(unsigned idx) { return m_bool_search->get_clause_info(idx); }
sat::ddfw::clause_info const& get_clause_info(unsigned idx) const { return m_bool_search->get_clause_info(idx); }
atom_info* atom(sat::literal lit) const { return m_atoms[lit.index()]; }
rational& dts(unsigned idx) { return m_clauses[idx].m_dts; }
bool flip();
void log() {}
bool flip_unsat();
bool flip_clauses();
bool flip_dscore();
bool flip_dscore(unsigned cl);
bool flip(unsigned cl);
rational dtt(ineq const& ineq) const { return dtt(ineq.m_args_value, ineq); }
rational dtt(rational const& args, ineq const& ineq) const;
rational dtt(ineq const& ineq, var_t v, rational const& new_value) const;
rational dts(unsigned cl, var_t v, rational const& new_value) const;
rational dts(unsigned cl) const;
bool cm(ineq const& ineq, var_t v, rational& new_value);
int cm_score(var_t v, rational const& new_value);
void update(var_t v, rational const& new_value);
void paws();
rational dscore(var_t v, rational const& new_value) const;
void save_best_values() {}
rational value(var_t v) const { return m_vars[v].m_value; }
public:
sls(solver& s);
void operator ()(bool_vector& phase);
void set_bounds_begin();
void set_bounds_end(unsigned num_literals);
void set_bounds(enode* n);
void set(sat::ddfw* d) { m_bool_search = d; }
};
sls m_local_search;
typedef vector<std::pair<rational, lpvar>> var_coeffs;