diff --git a/src/api/api_opt.cpp b/src/api/api_opt.cpp
index 71f92eeba..45832b5b6 100644
--- a/src/api/api_opt.cpp
+++ b/src/api/api_opt.cpp
@@ -124,10 +124,16 @@ extern "C" {
}
- Z3_lbool Z3_API Z3_optimize_check(Z3_context c, Z3_optimize o) {
+ Z3_lbool Z3_API Z3_optimize_check(Z3_context c, Z3_optimize o, unsigned num_assumptions, Z3_ast const assumptions[]) {
Z3_TRY;
- LOG_Z3_optimize_check(c, o);
+ LOG_Z3_optimize_check(c, o, num_assumptions, assumptions);
RESET_ERROR_CODE();
+ for (unsigned i = 0; i < num_assumptions; i++) {
+ if (!is_expr(to_ast(assumptions[i]))) {
+ SET_ERROR_CODE(Z3_INVALID_ARG, "assumption is not an expression");
+ return Z3_L_UNDEF;
+ }
+ }
lbool r = l_undef;
cancel_eh<reslimit> eh(mk_c(c)->m().limit());
unsigned timeout = to_optimize_ptr(o)->get_params().get_uint("timeout", mk_c(c)->get_timeout());
@@ -137,7 +143,9 @@ extern "C" {
scoped_timer timer(timeout, &eh);
scoped_rlimit _rlimit(mk_c(c)->m().limit(), rlimit);
try {
- r = to_optimize_ptr(o)->optimize();
+ expr_ref_vector asms(mk_c(c)->m());
+ asms.append(num_assumptions, to_exprs(assumptions));
+ r = to_optimize_ptr(o)->optimize(asms);
}
catch (z3_exception& ex) {
if (!mk_c(c)->m().canceled()) {
@@ -157,6 +165,22 @@ extern "C" {
Z3_CATCH_RETURN(Z3_L_UNDEF);
}
+ Z3_ast_vector Z3_API Z3_optimize_get_unsat_core(Z3_context c, Z3_optimize o) {
+ Z3_TRY;
+ LOG_Z3_optimize_get_unsat_core(c, o);
+ RESET_ERROR_CODE();
+ expr_ref_vector core(mk_c(c)->m());
+ to_optimize_ptr(o)->get_unsat_core(core);
+ Z3_ast_vector_ref * v = alloc(Z3_ast_vector_ref, *mk_c(c), mk_c(c)->m());
+ mk_c(c)->save_object(v);
+ for (expr* e : core) {
+ v->m_ast_vector.push_back(e);
+ }
+ RETURN_Z3(of_ast_vector(v));
+ Z3_CATCH_RETURN(nullptr);
+ }
+
+
Z3_string Z3_API Z3_optimize_get_reason_unknown(Z3_context c, Z3_optimize o) {
Z3_TRY;
LOG_Z3_optimize_to_string(c, o);
diff --git a/src/api/c++/z3++.h b/src/api/c++/z3++.h
index a283571d0..13232dd28 100644
--- a/src/api/c++/z3++.h
+++ b/src/api/c++/z3++.h
@@ -2455,8 +2455,20 @@ namespace z3 {
void pop() {
Z3_optimize_pop(ctx(), m_opt);
}
- check_result check() { Z3_lbool r = Z3_optimize_check(ctx(), m_opt); check_error(); return to_check_result(r); }
+ check_result check() { Z3_lbool r = Z3_optimize_check(ctx(), m_opt, 0, 0); check_error(); return to_check_result(r); }
+ check_result check(expr_vector const& asms) {
+ unsigned n = asms.size();
+ array<Z3_ast> _asms(n);
+ for (unsigned i = 0; i < n; i++) {
+ check_context(*this, asms[i]);
+ _asms[i] = asms[i];
+ }
+ Z3_lbool r = Z3_optimize_check(ctx(), m_opt, n, _asms.ptr());
+ check_error();
+ return to_check_result(r);
+ }
model get_model() const { Z3_model m = Z3_optimize_get_model(ctx(), m_opt); check_error(); return model(ctx(), m); }
+ expr_vector unsat_core() const { Z3_ast_vector r = Z3_optimize_get_unsat_core(ctx(), m_opt); check_error(); return expr_vector(ctx(), r); }
void set(params const & p) { Z3_optimize_set_params(ctx(), m_opt, p); check_error(); }
expr lower(handle const& h) {
Z3_ast r = Z3_optimize_get_lower(ctx(), m_opt, h.h());
diff --git a/src/api/dotnet/Optimize.cs b/src/api/dotnet/Optimize.cs
index 29e5e869a..ce3cc55f7 100644
--- a/src/api/dotnet/Optimize.cs
+++ b/src/api/dotnet/Optimize.cs
@@ -183,9 +183,9 @@ namespace Microsoft.Z3
/// don't use strict inequalities) meets the objectives.
/// </summary>
///
- public Status Check()
+ public Status Check(params Expr[] assumptions)
{
- Z3_lbool r = (Z3_lbool)Native.Z3_optimize_check(Context.nCtx, NativeObject);
+ Z3_lbool r = (Z3_lbool)Native.Z3_optimize_check(Context.nCtx, NativeObject, (uint)assumptions.Length, AST.ArrayToNative(assumptions));
switch (r)
{
case Z3_lbool.Z3_L_TRUE:
@@ -236,6 +236,25 @@ namespace Microsoft.Z3
}
}
+ /// <summary>
+ /// The unsat core of the last <c>Check</c>.
+ /// </summary>
+ /// <remarks>
+ /// The unsat core is a subset of <c>assumptions</c>
+ /// The result is empty if <c>Check</c> was not invoked before,
+ /// if its results was not <c>UNSATISFIABLE</c>, or if core production is disabled.
+ /// </remarks>
+ public BoolExpr[] UnsatCore
+ {
+ get
+ {
+ Contract.Ensures(Contract.Result<Expr[]>() != null);
+
+ ASTVector core = new ASTVector(Context, Native.Z3_optimize_get_unsat_core(Context.nCtx, NativeObject));
+ return core.ToBoolExprArray();
+ }
+ }
+
/// <summary>
/// Declare an arithmetical maximization objective.
/// Return a handle to the objective. The handle is used as
diff --git a/src/api/java/Optimize.java b/src/api/java/Optimize.java
index c5f8f9449..a91e2a573 100644
--- a/src/api/java/Optimize.java
+++ b/src/api/java/Optimize.java
@@ -161,9 +161,23 @@ public class Optimize extends Z3Object {
* Produce a model that (when the objectives are bounded and
* don't use strict inequalities) meets the objectives.
**/
- public Status Check()
+ public Status Check(Expr... assumptions)
{
- Z3_lbool r = Z3_lbool.fromInt(Native.optimizeCheck(getContext().nCtx(), getNativeObject()));
+ Z3_lbool r;
+ if (assumptions == null) {
+ r = Z3_lbool.fromInt(
+ Native.optimizeCheck(
+ getContext().nCtx(),
+ getNativeObject(), 0, null);
+ }
+ else {
+ r = Z3_lbool.fromInt(
+ Native.optimizeCheck(
+ getContext().nCtx(),
+ getNativeObject(),
+ assumptions.length,
+ AST.arrayToNative(assumptions)));
+ }
switch (r) {
case Z3_L_TRUE:
return Status.SATISFIABLE;
@@ -209,6 +223,21 @@ public class Optimize extends Z3Object {
}
}
+ /**
+ * The unsat core of the last {@code Check}.
+ * Remarks: The unsat core
+ * is a subset of {@code Assumptions} The result is empty if
+ * {@code Check} was not invoked before, if its results was not
+ * {@code UNSATISFIABLE}, or if core production is disabled.
+ *
+ * @throws Z3Exception
+ **/
+ public BoolExpr[] getUnsatCore()
+ {
+ ASTVector core = new ASTVector(getContext(), Native.optimizeGetUnsatCore(getContext().nCtx(), getNativeObject()));
+ return core.ToBoolExprArray();
+ }
+
/**
* Declare an arithmetical maximization objective.
* Return a handle to the objective. The handle is used as
diff --git a/src/api/ml/z3.ml b/src/api/ml/z3.ml
index 231587729..2ad07aee4 100644
--- a/src/api/ml/z3.ml
+++ b/src/api/ml/z3.ml
@@ -1947,7 +1947,7 @@ struct
let minimize (x:optimize) (e:Expr.expr) = mk_handle x (Z3native.optimize_minimize (gc x) x e)
let check (x:optimize) =
- let r = lbool_of_int (Z3native.optimize_check (gc x) x) in
+ let r = lbool_of_int (Z3native.optimize_check (gc x) x) 0 [] in
match r with
| L_TRUE -> Solver.SATISFIABLE
| L_FALSE -> Solver.UNSATISFIABLE
diff --git a/src/api/python/z3/z3.py b/src/api/python/z3/z3.py
index cefe8bbbb..703105356 100644
--- a/src/api/python/z3/z3.py
+++ b/src/api/python/z3/z3.py
@@ -7311,10 +7311,15 @@ class Optimize(Z3PPObject):
"""restore to previously created backtracking point"""
Z3_optimize_pop(self.ctx.ref(), self.optimize)
- def check(self):
+ def check(self, *assumptions):
"""Check satisfiability while optimizing objective functions."""
- return CheckSatResult(Z3_optimize_check(self.ctx.ref(), self.optimize))
-
+ assumptions = _get_args(assumptions)
+ num = len(assumptions)
+ _assumptions = (Ast * num)()
+ for i in range(num):
+ _assumptions[i] = assumptions[i].as_ast()
+ return CheckSatResult(Z3_optimize_check(self.ctx.ref(), self.optimize, num, _assumptions))
+
def reason_unknown(self):
"""Return a string that describes why the last `check()` returned `unknown`."""
return Z3_optimize_get_reason_unknown(self.ctx.ref(), self.optimize)
@@ -7326,6 +7331,9 @@ class Optimize(Z3PPObject):
except Z3Exception:
raise Z3Exception("model is not available")
+ def unsat_core(self):
+ return AstVector(Z3_optimize_get_unsat_core(self.ctx.ref(), self.optimize), self.ctx)
+
def lower(self, obj):
if not isinstance(obj, OptimizeObjective):
raise Z3Exception("Expecting objective handle returned by maximize/minimize")
diff --git a/src/api/z3_optimization.h b/src/api/z3_optimization.h
index f49e1b9ce..8f9e2470c 100644
--- a/src/api/z3_optimization.h
+++ b/src/api/z3_optimization.h
@@ -117,10 +117,12 @@ extern "C" {
\brief Check consistency and produce optimal values.
\param c - context
\param o - optimization context
+ \param num_assumptions - number of additional assumptions
+ \param assumptions - the additional assumptions
- def_API('Z3_optimize_check', INT, (_in(CONTEXT), _in(OPTIMIZE)))
+ def_API('Z3_optimize_check', INT, (_in(CONTEXT), _in(OPTIMIZE), _in(UINT), _in_array(2, AST)))
*/
- Z3_lbool Z3_API Z3_optimize_check(Z3_context c, Z3_optimize o);
+ Z3_lbool Z3_API Z3_optimize_check(Z3_context c, Z3_optimize o, unsigned num_assumptions, Z3_ast const assumptions[]);
/**
@@ -143,6 +145,14 @@ extern "C" {
*/
Z3_model Z3_API Z3_optimize_get_model(Z3_context c, Z3_optimize o);
+ /**
+ \brief Retrieve the unsat core for the last #Z3_optimize_chec
+ The unsat core is a subset of the assumptions \c a.
+
+ def_API('Z3_optimize_get_unsat_core', AST_VECTOR, (_in(CONTEXT), _in(OPTIMIZE)))
+ */
+ Z3_ast_vector Z3_API Z3_optimize_get_unsat_core(Z3_context c, Z3_optimize o);
+
/**
\brief Set parameters on optimization context.
diff --git a/src/cmd_context/cmd_context.cpp b/src/cmd_context/cmd_context.cpp
index be3acc261..89fb4f3cc 100644
--- a/src/cmd_context/cmd_context.cpp
+++ b/src/cmd_context/cmd_context.cpp
@@ -1488,13 +1488,13 @@ void cmd_context::check_sat(unsigned num_assumptions, expr * const * assumptions
scoped_ctrl_c ctrlc(eh);
scoped_timer timer(timeout, &eh);
scoped_rlimit _rlimit(m().limit(), rlimit);
+ expr_ref_vector asms(m());
+ asms.append(num_assumptions, assumptions);
if (!m_processing_pareto) {
- ptr_vector<expr> cnstr(m_assertions);
- cnstr.append(num_assumptions, assumptions);
- get_opt()->set_hard_constraints(cnstr);
+ get_opt()->set_hard_constraints(m_assertions);
}
try {
- r = get_opt()->optimize();
+ r = get_opt()->optimize(asms);
if (r == l_true && get_opt()->is_pareto()) {
m_processing_pareto = true;
}
diff --git a/src/cmd_context/cmd_context.h b/src/cmd_context/cmd_context.h
index a0093191d..87d80babe 100644
--- a/src/cmd_context/cmd_context.h
+++ b/src/cmd_context/cmd_context.h
@@ -148,7 +148,7 @@ public:
virtual bool empty() = 0;
virtual void push() = 0;
virtual void pop(unsigned n) = 0;
- virtual lbool optimize() = 0;
+ virtual lbool optimize(expr_ref_vector const& asms) = 0;
virtual void set_hard_constraints(ptr_vector<expr> & hard) = 0;
virtual void display_assignment(std::ostream& out) = 0;
virtual bool is_pareto() = 0;
diff --git a/src/opt/opt_context.cpp b/src/opt/opt_context.cpp
index 74d1ca955..8d7639851 100644
--- a/src/opt/opt_context.cpp
+++ b/src/opt/opt_context.cpp
@@ -130,6 +130,7 @@ namespace opt {
m_fm(alloc(generic_model_converter, m, "opt")),
m_model_fixed(),
m_objective_refs(m),
+ m_core(m),
m_enable_sat(false),
m_is_clausal(false),
m_pp_neat(false),
@@ -173,10 +174,9 @@ namespace opt {
}
void context::get_unsat_core(expr_ref_vector & r) {
- throw default_exception("Unsat cores are not supported with optimization");
+ r.append(m_core);
}
-
void context::set_hard_constraints(ptr_vector<expr>& fmls) {
if (m_scoped_state.set(fmls)) {
clear_state();
@@ -253,7 +253,7 @@ namespace opt {
m_hard_constraints.append(s.m_hard);
}
- lbool context::optimize() {
+ lbool context::optimize(expr_ref_vector const& asms) {
if (m_pareto) {
return execute_pareto();
}
@@ -263,7 +263,10 @@ namespace opt {
clear_state();
init_solver();
import_scoped_state();
- normalize();
+ normalize(asms);
+ if (m_hard_constraints.size() == 1 && m.is_false(m_hard_constraints.get(0))) {
+ return l_false;
+ }
internalize();
update_solver();
if (contains_quantifiers()) {
@@ -281,7 +284,7 @@ namespace opt {
symbol pri = optp.priority();
IF_VERBOSE(1, verbose_stream() << "(optimize:check-sat)\n");
- lbool is_sat = s.check_sat(0,nullptr);
+ lbool is_sat = s.check_sat(asms.size(),asms.c_ptr());
TRACE("opt", s.display(tout << "initial search result: " << is_sat << "\n"););
if (is_sat != l_false) {
s.get_model(m_model);
@@ -290,6 +293,9 @@ namespace opt {
}
if (is_sat != l_true) {
TRACE("opt", tout << m_hard_constraints << "\n";);
+ if (!asms.empty()) {
+ s.get_unsat_core(m_core);
+ }
return is_sat;
}
IF_VERBOSE(1, verbose_stream() << "(optimize:sat)\n");
@@ -749,22 +755,25 @@ namespace opt {
return m_arith.is_numeral(e, n) || m_bv.is_numeral(e, n, sz);
}
- void context::normalize() {
+ void context::normalize(expr_ref_vector const& asms) {
expr_ref_vector fmls(m);
to_fmls(fmls);
- simplify_fmls(fmls);
+ simplify_fmls(fmls, asms);
from_fmls(fmls);
}
- void context::simplify_fmls(expr_ref_vector& fmls) {
+ void context::simplify_fmls(expr_ref_vector& fmls, expr_ref_vector const& asms) {
if (m_is_clausal) {
return;
}
- goal_ref g(alloc(goal, m, true, false));
+ goal_ref g(alloc(goal, m, true, !asms.empty()));
for (expr* fml : fmls) {
g->assert_expr(fml);
}
+ for (expr * a : asms) {
+ g->assert_expr(a, a);
+ }
tactic_ref tac0 =
and_then(mk_simplify_tactic(m, m_params),
mk_propagate_values_tactic(m),
@@ -786,6 +795,7 @@ namespace opt {
set_simplify(tac0.get());
}
goal_ref_buffer result;
+ TRACE("opt", g->display(tout););
(*m_simplify)(g, result);
SASSERT(result.size() == 1);
goal* r = result[0];
@@ -795,6 +805,12 @@ namespace opt {
for (unsigned i = 0; i < r->size(); ++i) {
fmls.push_back(r->form(i));
}
+ if (r->inconsistent()) {
+ ptr_vector<expr> core_elems;
+ expr_dependency_ref core(r->dep(0), m);
+ m.linearize(core, core_elems);
+ m_core.append(core_elems.size(), core_elems.c_ptr());
+ }
}
bool context::is_maximize(expr* fml, app_ref& term, expr_ref& orig_term, unsigned& index) {
@@ -1393,6 +1409,7 @@ namespace opt {
m_box_index = UINT_MAX;
m_model.reset();
m_model_fixed.reset();
+ m_core.reset();
}
void context::set_pareto(pareto_base* p) {
diff --git a/src/opt/opt_context.h b/src/opt/opt_context.h
index 1172e68b6..f57e937ba 100644
--- a/src/opt/opt_context.h
+++ b/src/opt/opt_context.h
@@ -164,6 +164,7 @@ namespace opt {
obj_map<func_decl, unsigned> m_objective_fns;
obj_map<func_decl, expr*> m_objective_orig;
func_decl_ref_vector m_objective_refs;
+ expr_ref_vector m_core;
tactic_ref m_simplify;
bool m_enable_sat;
bool m_enable_sls;
@@ -187,7 +188,7 @@ namespace opt {
void pop(unsigned n) override;
bool empty() override { return m_scoped_state.m_objectives.empty(); }
void set_hard_constraints(ptr_vector<expr> & hard) override;
- lbool optimize() override;
+ lbool optimize(expr_ref_vector const& asms) override;
void set_model(model_ref& _m) override { m_model = _m; }
void get_model_core(model_ref& _m) override;
void get_box_model(model_ref& _m, unsigned index) override;
@@ -254,7 +255,7 @@ namespace opt {
void reset_maxsmts();
void import_scoped_state();
- void normalize();
+ void normalize(expr_ref_vector const& asms);
void internalize();
bool is_maximize(expr* fml, app_ref& term, expr_ref& orig_term, unsigned& index);
bool is_minimize(expr* fml, app_ref& term, expr_ref& orig_term, unsigned& index);
@@ -270,7 +271,7 @@ namespace opt {
expr* mk_objective_fn(unsigned index, objective_t ty, unsigned sz, expr*const* args);
void to_fmls(expr_ref_vector& fmls);
void from_fmls(expr_ref_vector const& fmls);
- void simplify_fmls(expr_ref_vector& fmls);
+ void simplify_fmls(expr_ref_vector& fmls, expr_ref_vector const& asms);
void mk_atomic(expr_ref_vector& terms);
void update_lower() { update_bound(true); }
diff --git a/src/sat/sat_solver.cpp b/src/sat/sat_solver.cpp
index b65abd41c..426caa6dd 100644
--- a/src/sat/sat_solver.cpp
+++ b/src/sat/sat_solver.cpp
@@ -78,6 +78,8 @@ namespace sat {
del_clauses(m_clauses);
TRACE("sat", tout << "Delete learned\n";);
del_clauses(m_learned);
+ dealloc(m_cuber);
+ m_cuber = nullptr;
}
void solver::del_clauses(clause_vector& clauses) {
diff --git a/src/shell/opt_frontend.cpp b/src/shell/opt_frontend.cpp
index 0a2a8f4a1..afa7b79c5 100644
--- a/src/shell/opt_frontend.cpp
+++ b/src/shell/opt_frontend.cpp
@@ -108,7 +108,8 @@ static unsigned parse_opt(std::istream& in, opt_format f) {
unsigned rlimit = std::stoi(gparams::get_value("rlimit"));
scoped_timer timer(timeout, &eh);
scoped_rlimit _rlimit(m.limit(), rlimit);
- lbool r = opt.optimize();
+ expr_ref_vector asms(m);
+ lbool r = opt.optimize(asms);
switch (r) {
case l_true: std::cout << "sat\n"; break;
case l_false: std::cout << "unsat\n"; break;