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init search before returning

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2017-06-11 13:08:05 -07:00
parent b266af3e08
commit af6ebbcd92
16 changed files with 90 additions and 37 deletions

View file

@ -479,12 +479,14 @@ extern "C" {
Z3_ast Z3_API Z3_solver_lookahead(Z3_context c,
Z3_solver s,
Z3_ast_vector assumptions,
Z3_ast_vector candidates) {
Z3_TRY;
LOG_Z3_solver_lookahead(c, s, candidates);
LOG_Z3_solver_lookahead(c, s, assumptions, candidates);
ast_manager& m = mk_c(c)->m();
expr_ref_vector _candidates(m);
expr_ref_vector _candidates(m), _assumptions(m);
ast_ref_vector const& __candidates = to_ast_vector_ref(candidates);
ast_ref_vector const& __assumptions = to_ast_vector_ref(assumptions);
for (auto & e : __candidates) {
if (!is_expr(e)) {
SET_ERROR_CODE(Z3_INVALID_USAGE);
@ -492,6 +494,13 @@ extern "C" {
}
_candidates.push_back(to_expr(e));
}
for (auto & e : __assumptions) {
if (!is_expr(e)) {
SET_ERROR_CODE(Z3_INVALID_USAGE);
return 0;
}
_assumptions.push_back(to_expr(e));
}
expr_ref result(m);
unsigned timeout = to_solver(s)->m_params.get_uint("timeout", mk_c(c)->get_timeout());
@ -504,7 +513,7 @@ extern "C" {
scoped_timer timer(timeout, &eh);
scoped_rlimit _rlimit(mk_c(c)->m().limit(), rlimit);
try {
result = to_solver_ref(s)->lookahead(_candidates);
result = to_solver_ref(s)->lookahead(_assumptions, _candidates);
}
catch (z3_exception & ex) {
mk_c(c)->handle_exception(ex);

View file

@ -255,11 +255,13 @@ namespace Microsoft.Z3
/// <summary>
/// Select a lookahead literal from the set of supplied candidates.
/// </summary>
public BoolExpr Lookahead(IEnumerable<BoolExpr> candidates)
public BoolExpr Lookahead(IEnumerable<BoolExpr> assumptions, IEnumerable<BoolExpr> candidates)
{
ASTVector cands = new ASTVector(Context);
foreach (var c in candidates) cands.Push(c);
return (BoolExpr)Expr.Create(Context, Native.Z3_solver_lookahead(Context.nCtx, NativeObject, cands.NativeObject));
ASTVector assums = new ASTVector(Context);
foreach (var c in assumptions) assums.Push(c);
return (BoolExpr)Expr.Create(Context, Native.Z3_solver_lookahead(Context.nCtx, NativeObject, assums.NativeObject, cands.NativeObject));
}
/// <summary>

View file

@ -6028,10 +6028,10 @@ extern "C" {
\brief select a literal from the list of candidate propositional variables to split on.
If the candidate list is empty, then the solver chooses a formula based on its internal state.
def_API('Z3_solver_lookahead', AST, (_in(CONTEXT), _in(SOLVER), _in(AST_VECTOR)))
def_API('Z3_solver_lookahead', AST, (_in(CONTEXT), _in(SOLVER), _in(AST_VECTOR), _in(AST_VECTOR)))
*/
Z3_ast Z3_API Z3_solver_lookahead(Z3_context c, Z3_solver s, Z3_ast_vector candidates);
Z3_ast Z3_API Z3_solver_lookahead(Z3_context c, Z3_solver s, Z3_ast_vector assumptions, Z3_ast_vector candidates);
/**

View file

@ -107,7 +107,7 @@ namespace opt {
virtual ast_manager& get_manager() const { return m; }
virtual lbool find_mutexes(expr_ref_vector const& vars, vector<expr_ref_vector>& mutexes);
virtual lbool preferred_sat(expr_ref_vector const& asms, vector<expr_ref_vector>& cores);
virtual expr_ref lookahead(expr_ref_vector const& candidates) { return expr_ref(m.mk_true(), m); }
virtual expr_ref lookahead(expr_ref_vector const& assumptions, expr_ref_vector const& candidates) { return expr_ref(m.mk_true(), m); }
void set_logic(symbol const& logic);
smt::theory_var add_objective(app* term);

View file

@ -30,6 +30,18 @@ namespace sat {
if (p.m_s.m_ext) p.m_s.m_ext->set_lookahead(0);
}
lookahead::scoped_assumptions::scoped_assumptions(lookahead& p, literal_vector const& lits): p(p), lits(lits) {
for (auto l : lits) {
p.push(l, p.c_fixed_truth);
}
}
lookahead::scoped_assumptions::~scoped_assumptions() {
for (auto l : lits) {
p.pop();
}
}
void lookahead::flip_prefix() {
if (m_trail_lim.size() < 64) {
uint64 mask = (1ull << m_trail_lim.size());
@ -1612,7 +1624,7 @@ namespace sat {
}
literal lookahead::select_lookahead(bool_var_vector const& vars) {
literal lookahead::select_lookahead(literal_vector const& assumptions, bool_var_vector const& vars) {
IF_VERBOSE(1, verbose_stream() << "(sat-select " << vars.size() << ")\n";);
scoped_ext _sext(*this);
m_search_mode = lookahead_mode::searching;
@ -1623,19 +1635,25 @@ namespace sat {
for (auto v : vars) {
m_select_lookahead_vars.insert(v);
}
scoped_assumptions _sa(*this, assumptions);
literal l = choose();
m_select_lookahead_vars.reset();
if (inconsistent()) return null_literal;
if (inconsistent()) l = null_literal;
#if 0
// assign unit literals that were found during search for lookahead.
unsigned num_assigned = 0;
for (literal lit : m_trail) {
if (!m_s.was_eliminated(lit.var()) && m_s.value(lit) != l_true) {
m_s.assign(lit, justification());
++num_assigned;
if (assumptions.empty()) {
unsigned num_assigned = 0;
for (literal lit : m_trail) {
if (!m_s.was_eliminated(lit.var()) && m_s.value(lit) != l_true) {
m_s.assign(lit, justification());
++num_assigned;
}
}
IF_VERBOSE(1, verbose_stream() << "(sat-lookahead :units " << num_assigned << ")\n";);
}
IF_VERBOSE(1, verbose_stream() << "(sat-lookahead :units " << num_assigned << ")\n";);
#endif
return l;
}

View file

@ -199,6 +199,14 @@ namespace sat {
~scoped_ext();
};
class scoped_assumptions {
lookahead& p;
literal_vector lits;
public:
scoped_assumptions(lookahead& p, literal_vector const& lits);
~scoped_assumptions();
};
// -------------------------------------
// prefix updates. I use low order bits.
@ -447,7 +455,7 @@ namespace sat {
return search();
}
literal select_lookahead(bool_var_vector const& vars);
literal select_lookahead(literal_vector const& assumptions, bool_var_vector const& vars);
/**
\brief simplify set of clauses by extracting units from a lookahead at base level.
*/

View file

@ -811,14 +811,9 @@ namespace sat {
return r;
}
literal solver::select_lookahead(bool_var_vector const& vars) {
literal solver::select_lookahead(literal_vector const& assumptions, bool_var_vector const& vars) {
lookahead lh(*this);
literal result = lh.select_lookahead(vars);
if (result == null_literal) {
set_conflict(justification());
}
// extract unit literals from lh
return result;
return lh.select_lookahead(assumptions, vars);
}
// -----------------------
@ -851,8 +846,8 @@ namespace sat {
}
#endif
try {
if (inconsistent()) return l_false;
init_search();
if (inconsistent()) return l_false;
propagate(false);
if (inconsistent()) return l_false;
init_assumptions(num_lits, lits);

View file

@ -355,7 +355,7 @@ namespace sat {
void set_model(model const& mdl);
char const* get_reason_unknown() const { return m_reason_unknown.c_str(); }
literal select_lookahead(bool_var_vector const& vars);
literal select_lookahead(literal_vector const& assumptions, bool_var_vector const& vars);
protected:
unsigned m_conflicts;

View file

@ -148,6 +148,8 @@ public:
virtual lbool check_sat(unsigned sz, expr * const * assumptions) {
m_solver.pop_to_base_level();
m_core.reset();
if (m_solver.inconsistent()) return l_false;
expr_ref_vector _assumptions(m);
obj_map<expr, expr*> asm2fml;
for (unsigned i = 0; i < sz; ++i) {
@ -280,9 +282,10 @@ public:
return 0;
}
virtual expr_ref lookahead(expr_ref_vector const& candidates) {
virtual expr_ref lookahead(expr_ref_vector const& assumptions, expr_ref_vector const& candidates) {
IF_VERBOSE(1, verbose_stream() << "(sat-lookahead " << candidates.size() << ")\n";);
sat::bool_var_vector vars;
sat::literal_vector lits;
expr_ref_vector lit2expr(m);
lit2expr.resize(m_solver.num_vars() * 2);
m_map.mk_inv(lit2expr);
@ -292,11 +295,29 @@ public:
vars.push_back(v);
}
}
for (auto c : assumptions) {
SASSERT(is_literal(c));
sat::bool_var v = sat::null_bool_var;
bool sign = false;
expr* e = c;
while (m.is_not(e, e)) {
sign = !sign;
}
if (is_uninterp_const(e)) {
v = m_map.to_bool_var(e);
}
if (v != sat::null_bool_var) {
lits.push_back(sat::literal(v, sign));
}
else {
IF_VERBOSE(0, verbose_stream() << "WARNING: could not handle " << mk_pp(c, m) << "\n";);
}
}
IF_VERBOSE(1, verbose_stream() << "vars: " << vars.size() << "\n";);
if (vars.empty()) {
return expr_ref(m.mk_true(), m);
}
sat::literal l = m_solver.select_lookahead(vars);
sat::literal l = m_solver.select_lookahead(lits, vars);
if (m_solver.inconsistent()) {
IF_VERBOSE(1, verbose_stream() << "(sat-lookahead inconsistent)\n";);
return expr_ref(m.mk_false(), m);
@ -715,7 +736,7 @@ private:
if (asm2fml.contains(e)) {
e = asm2fml.find(e);
}
m_core.push_back(e);
m_core.push_back(e);
}
}

View file

@ -219,7 +219,7 @@ namespace smt {
return m_context.get_formulas()[idx];
}
virtual expr_ref lookahead(expr_ref_vector const& candidates) {
virtual expr_ref lookahead(expr_ref_vector const& assumptions, expr_ref_vector const& candidates) {
ast_manager& m = get_manager();
return expr_ref(m.mk_true(), m);
}

View file

@ -274,8 +274,8 @@ public:
return m_solver1->get_num_assumptions() + m_solver2->get_num_assumptions();
}
virtual expr_ref lookahead(expr_ref_vector const& candidates) {
return m_solver1->lookahead(candidates);
virtual expr_ref lookahead(expr_ref_vector const& assumptions, expr_ref_vector const& candidates) {
return m_solver1->lookahead(assumptions, candidates);
}
virtual expr * get_assumption(unsigned idx) const {

View file

@ -176,7 +176,7 @@ public:
\brief extract a lookahead candidates for branching.
*/
virtual expr_ref lookahead(expr_ref_vector const& candidates) = 0;
virtual expr_ref lookahead(expr_ref_vector const& assumptions, expr_ref_vector const& candidates) = 0;
/**
\brief extract learned lemmas.

View file

@ -76,7 +76,7 @@ public:
virtual ast_manager& get_manager() const;
virtual expr_ref lookahead(expr_ref_vector const& candidates) {
virtual expr_ref lookahead(expr_ref_vector const& assumptions, expr_ref_vector const& candidates) {
ast_manager& m = get_manager();
std::cout << "tactic2solver\n";
return expr_ref(m.mk_true(), m);

View file

@ -149,7 +149,7 @@ public:
virtual void set_reason_unknown(char const* msg) { m_solver->set_reason_unknown(msg); }
virtual void get_labels(svector<symbol> & r) { m_solver->get_labels(r); }
virtual ast_manager& get_manager() const { return m; }
virtual expr_ref lookahead(expr_ref_vector const& candidates) { flush_assertions(); return m_solver->lookahead(candidates); }
virtual expr_ref lookahead(expr_ref_vector const& assumptions, expr_ref_vector const& candidates) { flush_assertions(); return m_solver->lookahead(assumptions, candidates); }
virtual void get_lemmas(expr_ref_vector & lemmas) { flush_assertions(); m_solver->get_lemmas(lemmas); }
virtual lbool find_mutexes(expr_ref_vector const& vars, vector<expr_ref_vector>& mutexes) { return m_solver->find_mutexes(vars, mutexes); }
virtual lbool get_consequences_core(expr_ref_vector const& asms, expr_ref_vector const& vars, expr_ref_vector& consequences) {

View file

@ -97,7 +97,7 @@ public:
virtual void get_labels(svector<symbol> & r) { m_solver->get_labels(r); }
virtual ast_manager& get_manager() const { return m; }
virtual lbool find_mutexes(expr_ref_vector const& vars, vector<expr_ref_vector>& mutexes) { return m_solver->find_mutexes(vars, mutexes); }
virtual expr_ref lookahead(expr_ref_vector const& candidates) { return m_solver->lookahead(candidates); }
virtual expr_ref lookahead(expr_ref_vector const& assumptions, expr_ref_vector const& candidates) { return m_solver->lookahead(assumptions, candidates); }
virtual void get_lemmas(expr_ref_vector & lemmas) { m_solver->get_lemmas(lemmas); }
virtual lbool get_consequences_core(expr_ref_vector const& asms, expr_ref_vector const& vars, expr_ref_vector& consequences) {

View file

@ -93,7 +93,7 @@ public:
virtual void set_reason_unknown(char const* msg) { m_solver->set_reason_unknown(msg); }
virtual void get_labels(svector<symbol> & r) { m_solver->get_labels(r); }
virtual ast_manager& get_manager() const { return m; }
virtual expr_ref lookahead(expr_ref_vector const& candidates) { flush_assertions(); return m_solver->lookahead(candidates); }
virtual expr_ref lookahead(expr_ref_vector const& assumptions, expr_ref_vector const& candidates) { flush_assertions(); return m_solver->lookahead(assumptions, candidates); }
virtual void get_lemmas(expr_ref_vector & lemmas) { flush_assertions(); m_solver->get_lemmas(lemmas); }
virtual lbool find_mutexes(expr_ref_vector const& vars, vector<expr_ref_vector>& mutexes) { return m_solver->find_mutexes(vars, mutexes); }
virtual lbool get_consequences_core(expr_ref_vector const& asms, expr_ref_vector const& vars, expr_ref_vector& consequences) {