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tidy & todo notes

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2013-10-19 12:22:56 -07:00
parent 53f78f7d19
commit 3996f58a8e
6 changed files with 86 additions and 44 deletions

View file

@ -37,13 +37,13 @@ namespace opt {
class fu_malik {
ast_manager& m;
::solver& s;
solver& s;
expr_ref_vector m_soft;
expr_ref_vector m_aux;
public:
fu_malik(ast_manager& m, ::solver& s, expr_ref_vector const& soft):
fu_malik(ast_manager& m, solver& s, expr_ref_vector const& soft):
m(m),
s(s),
m_soft(soft),
@ -132,7 +132,7 @@ namespace opt {
};
lbool fu_malik_maxsat(::solver& s, expr_ref_vector& soft_constraints) {
lbool fu_malik_maxsat(solver& s, expr_ref_vector& soft_constraints) {
ast_manager& m = soft_constraints.get_manager();
lbool is_sat = s.check_sat(0,0);
if (!soft_constraints.empty() && is_sat == l_true) {

View file

@ -28,7 +28,7 @@ namespace opt {
that are still consistent with the solver state.
*/
lbool fu_malik_maxsat(::solver& s, expr_ref_vector& soft_constraints);
lbool fu_malik_maxsat(solver& s, expr_ref_vector& soft_constraints);
};
#endif

View file

@ -14,12 +14,26 @@ Author:
Notes:
TODO:
- integrate with parameters.
Parameter infrastructure lets us control setttings, such as
timeouts and control which backend optimization approach to
use during experiments.
- Display statistics properly on exit when configured to do so.
Also add appropriate statistics tracking to opt::context
- Deal with push/pop (later)
- Revisit weighted constraints if we want to group them using identifiers.
--*/
#include "opt_cmds.h"
#include "cmd_context.h"
#include "ast_pp.h"
#include "opt_context.h"
#include "cancel_eh.h"
#include "scoped_ctrl_c.h"
class opt_context {
@ -37,13 +51,13 @@ public:
class assert_weighted_cmd : public cmd {
opt_context* m_opt_ctx;
unsigned m_idx;
expr* m_formula;
rational m_weight;
opt_context& m_opt_ctx;
unsigned m_idx;
expr* m_formula;
rational m_weight;
public:
assert_weighted_cmd(cmd_context& ctx, opt_context* opt_ctx):
assert_weighted_cmd(cmd_context& ctx, opt_context& opt_ctx):
cmd("assert-weighted"),
m_opt_ctx(opt_ctx),
m_idx(0),
@ -52,7 +66,7 @@ public:
{}
virtual ~assert_weighted_cmd() {
dealloc(m_opt_ctx);
dealloc(&m_opt_ctx);
}
virtual void reset(cmd_context & ctx) {
@ -94,7 +108,7 @@ public:
}
virtual void execute(cmd_context & ctx) {
(*m_opt_ctx)().add_soft_constraint(m_formula, m_weight);
m_opt_ctx().add_soft_constraint(m_formula, m_weight);
reset(ctx);
}
@ -103,23 +117,18 @@ public:
};
// what amounts to check-sat, but uses the *single* objective function.
// alternative is to register multiple objective functions using
// minimize/maximize and then use check-sat or some variant of it
// to do the feasibility check.
class min_maximize_cmd : public cmd {
bool m_is_max;
opt_context* m_opt_ctx;
bool m_is_max;
opt_context& m_opt_ctx;
public:
min_maximize_cmd(cmd_context& ctx, opt_context* opt_ctx, bool is_max):
min_maximize_cmd(cmd_context& ctx, opt_context& opt_ctx, bool is_max):
cmd(is_max?"maximize":"minimize"),
m_is_max(is_max),
m_opt_ctx(opt_ctx)
{}
virtual void reset(cmd_context & ctx) {
}
virtual void reset(cmd_context & ctx) { }
virtual char const * get_usage() const { return "<term>"; }
virtual char const * get_descr(cmd_context & ctx) const { return "check sat modulo objective function";}
@ -129,9 +138,7 @@ public:
virtual cmd_arg_kind next_arg_kind(cmd_context & ctx) const { return CPK_EXPR; }
virtual void set_next_arg(cmd_context & ctx, expr * t) {
// TODO: type check objective term. It should pass basic sanity being
// integer, real (, bit-vector) or other supported objective function type.
(*m_opt_ctx)().add_objective(t, m_is_max);
m_opt_ctx().add_objective(t, m_is_max);
}
virtual void failure_cleanup(cmd_context & ctx) {
@ -140,14 +147,12 @@ public:
virtual void execute(cmd_context & ctx) {
}
};
class optimize_cmd : public cmd {
opt_context* m_opt_ctx;
opt_context& m_opt_ctx;
public:
optimize_cmd(opt_context* opt_ctx):
optimize_cmd(opt_context& opt_ctx):
cmd("optimize"),
m_opt_ctx(opt_ctx)
{}
@ -159,25 +164,33 @@ public:
}
virtual void execute(cmd_context & ctx) {
opt::context& opt = m_opt_ctx();
ptr_vector<expr>::const_iterator it = ctx.begin_assertions();
ptr_vector<expr>::const_iterator end = ctx.end_assertions();
for (; it != end; ++it) {
(*m_opt_ctx)().add_hard_constraint(*it);
opt.add_hard_constraint(*it);
}
cancel_eh<opt::context> eh(opt);
{
scoped_ctrl_c ctrlc(eh);
cmd_context::scoped_watch sw(ctx);
try {
opt.optimize();
}
catch (z3_error& ex) {
ctx.regular_stream() << "(error: " << ex.msg() << "\")" << std::endl;
}
catch (z3_exception& ex) {
ctx.regular_stream() << "(error: " << ex.msg() << "\")" << std::endl;
}
}
(*m_opt_ctx)().optimize();
}
private:
};
void install_opt_cmds(cmd_context & ctx) {
opt_context* opt_ctx = alloc(opt_context, ctx);
ctx.insert(alloc(assert_weighted_cmd, ctx, opt_ctx));
ctx.insert(alloc(min_maximize_cmd, ctx, opt_ctx, true));
ctx.insert(alloc(min_maximize_cmd, ctx, opt_ctx, false));
ctx.insert(alloc(optimize_cmd, opt_ctx));
ctx.insert(alloc(assert_weighted_cmd, ctx, *opt_ctx));
ctx.insert(alloc(min_maximize_cmd, ctx, *opt_ctx, true));
ctx.insert(alloc(min_maximize_cmd, ctx, *opt_ctx, false));
ctx.insert(alloc(optimize_cmd, *opt_ctx));
}

View file

@ -14,6 +14,13 @@ Author:
Notes:
TODO:
- there are race conditions for cancelation.
- it would also be a good idea to maintain a volatile bool to track
cancelation and then bail out of loops inside optimize() and derived
functions.
--*/
#include "opt_context.h"
@ -95,4 +102,16 @@ namespace opt {
return true;
}
void context::cancel() {
if (m_solver) {
m_solver->cancel();
}
}
void context::reset_cancel() {
if (m_solver) {
m_solver->reset_cancel();
}
}
}

View file

@ -14,6 +14,13 @@ Author:
Notes:
TODO:
- type check objective term and assertions. It should pass basic sanity being
integer, real (, bit-vector) or other supported objective function type.
- add appropriate statistics tracking to opt::context
--*/
#ifndef _OPT_CONTEXT_H_
#define _OPT_CONTEXT_H_
@ -31,7 +38,7 @@ namespace opt {
expr_ref_vector m_objectives;
svector<bool> m_is_max;
ref<::solver> m_solver;
ref<solver> m_solver;
public:
context(ast_manager& m):
@ -55,12 +62,15 @@ namespace opt {
m_hard_constraints.push_back(f);
}
void set_solver(::solver* s) {
void set_solver(solver* s) {
m_solver = s;
}
void optimize();
void cancel();
void reset_cancel();
private:
bool is_maxsat_problem() const;

View file

@ -28,11 +28,11 @@ namespace smt {
public:
virtual bool maximize(theory_var v) { UNREACHABLE(); return false; };
virtual theory_var add_objective(app* term) { UNREACHABLE(); return null_theory_var; }
virtual inf_eps_rational<rational> get_objective_value(theory_var v) {
virtual inf_eps_rational<rational> get_objective_value(theory_var v) {
UNREACHABLE();
inf_eps_rational<rational> r(rational(1), rational(0));
return r;
}
}
};
}