z3-z3-4.13.0.src.smt.theory_opt.cpp Maven / Gradle / Ivy
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/*++
Copyright (c) 2013 Microsoft Corporation
Module Name:
theory_opt.cpp
Abstract:
Interface utilities used by optimization providing
theory solvers.
Author:
Nikolaj Bjorner (nbjorner) 2013-10-18
Notes:
--*/
#include "ast/arith_decl_plugin.h"
#include "smt/smt_types.h"
#include "smt/smt_theory.h"
#include "smt/theory_opt.h"
namespace smt {
bool theory_opt::is_linear(ast_manager& m, expr* term) {
arith_util a(m);
ptr_vector todo;
ast_mark mark;
todo.push_back(term);
expr* t1, *t2;
while (!todo.empty()) {
term = todo.back();
todo.pop_back();
if (mark.is_marked(term)) {
continue;
}
mark.mark(term, true);
if (!is_app(term)) {
return false;
}
app* t = to_app(term);
if (t->get_family_id() != a.get_family_id()) {
// done
}
else if (a.is_add(t) || a.is_to_real(t) || a.is_to_int(t) ||
a.is_uminus(t) || a.is_numeral(t) || a.is_sub(t)) {
todo.append(t->get_num_args(), t->get_args());
}
else if (a.is_mul(t, t1, t2)) {
if (is_numeral(a, t1)) {
todo.push_back(t2);
}
else if (is_numeral(a, t2)) {
todo.push_back(t1);
}
else {
return false;
}
}
else {
return false;
}
}
return true;
}
bool theory_opt::is_numeral(arith_util& a, expr* term) {
while (a.is_uminus(term) || a.is_to_real(term) || a.is_to_int(term)) {
term = to_app(term)->get_arg(0);
}
return a.is_numeral(term);
}
};