mirror of
https://github.com/Z3Prover/z3
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700 lines
27 KiB
C++
700 lines
27 KiB
C++
/*++
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Copyright (c) 2015 Microsoft Corporation
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Module Name:
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qe_arith.cpp
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Abstract:
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Simple projection function for real arithmetic based on Loos-W.
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Author:
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Nikolaj Bjorner (nbjorner) 2013-09-12
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Revision History:
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Moved projection functionality to model_based_opt module. 2016-06-26
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--*/
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#include "qe/mbp/mbp_arith.h"
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#include "ast/ast_util.h"
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#include "ast/arith_decl_plugin.h"
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#include "ast/ast_pp.h"
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#include "ast/expr_functors.h"
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#include "ast/rewriter/expr_safe_replace.h"
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#include "math/simplex/model_based_opt.h"
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#include "model/model_evaluator.h"
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#include "model/model_smt2_pp.h"
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#include "model/model_v2_pp.h"
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namespace mbp {
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struct arith_project_plugin::imp {
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ast_manager& m;
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arith_util a;
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bool m_check_purified = true; // check that variables are properly pure
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bool m_apply_projection = false;
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imp(ast_manager& m) :
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m(m), a(m) {}
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~imp() {}
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void insert_mul(expr* x, rational const& v, obj_map<expr, rational>& ts) {
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rational w;
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if (ts.find(x, w))
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ts.insert(x, w + v);
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else
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ts.insert(x, v);
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}
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//
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// extract linear inequalities from literal 'lit' into the model-based optimization manager 'mbo'.
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// It uses the current model to choose values for conditionals and it primes mbo with the current
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// interpretation of sub-expressions that are treated as variables for mbo.
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//
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bool linearize(opt::model_based_opt& mbo, model_evaluator& eval, expr* lit, expr_ref_vector& fmls, obj_map<expr, unsigned>& tids) {
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obj_map<expr, rational> ts;
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rational c(0), mul(1);
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expr_ref t(m);
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opt::ineq_type ty = opt::t_le;
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expr* e1, * e2;
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DEBUG_CODE(expr_ref val(m);
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eval(lit, val);
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CTRACE("qe", !m.is_true(val), tout << mk_pp(lit, m) << " := " << val << "\n";);
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SASSERT(m.limit().is_canceled() || !m.is_false(val)););
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if (!m.inc())
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return false;
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TRACE("opt", tout << mk_pp(lit, m) << " " << a.is_lt(lit) << " " << a.is_gt(lit) << "\n";);
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bool is_not = m.is_not(lit, lit);
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if (is_not) {
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mul.neg();
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}
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SASSERT(!m.is_not(lit));
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if ((a.is_le(lit, e1, e2) || a.is_ge(lit, e2, e1))) {
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linearize(mbo, eval, mul, e1, c, fmls, ts, tids);
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linearize(mbo, eval, -mul, e2, c, fmls, ts, tids);
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ty = is_not ? opt::t_lt : opt::t_le;
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}
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else if ((a.is_lt(lit, e1, e2) || a.is_gt(lit, e2, e1))) {
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linearize(mbo, eval, mul, e1, c, fmls, ts, tids);
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linearize(mbo, eval, -mul, e2, c, fmls, ts, tids);
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ty = is_not ? opt::t_le : opt::t_lt;
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}
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else if (m.is_eq(lit, e1, e2) && !is_not && is_arith(e1)) {
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linearize(mbo, eval, mul, e1, c, fmls, ts, tids);
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linearize(mbo, eval, -mul, e2, c, fmls, ts, tids);
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ty = opt::t_eq;
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}
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else if (m.is_eq(lit, e1, e2) && is_not && is_arith(e1)) {
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rational r1, r2;
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expr_ref val1 = eval(e1);
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expr_ref val2 = eval(e2);
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if (!a.is_numeral(val1, r1)) return false;
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if (!a.is_numeral(val2, r2)) return false;
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SASSERT(r1 != r2);
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if (r1 < r2) {
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std::swap(e1, e2);
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}
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ty = opt::t_lt;
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linearize(mbo, eval, mul, e1, c, fmls, ts, tids);
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linearize(mbo, eval, -mul, e2, c, fmls, ts, tids);
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}
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else if (m.is_distinct(lit) && !is_not && is_arith(to_app(lit)->get_arg(0))) {
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expr_ref val(m);
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rational r;
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app* alit = to_app(lit);
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vector<std::pair<expr*, rational> > nums;
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for (expr* arg : *alit) {
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val = eval(arg);
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TRACE("qe", tout << mk_pp(arg, m) << " " << val << "\n";);
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if (!a.is_numeral(val, r)) return false;
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nums.push_back(std::make_pair(arg, r));
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}
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std::sort(nums.begin(), nums.end(), compare_second());
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for (unsigned i = 0; i + 1 < nums.size(); ++i) {
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SASSERT(nums[i].second < nums[i + 1].second);
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expr_ref fml(a.mk_lt(nums[i].first, nums[i + 1].first), m);
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if (!linearize(mbo, eval, fml, fmls, tids)) {
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return false;
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}
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}
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return true;
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}
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else if (m.is_distinct(lit) && is_not && is_arith(to_app(lit)->get_arg(0))) {
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// find the two arguments that are equal.
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// linearize these.
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map<rational, expr*, rational::hash_proc, rational::eq_proc> values;
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bool found_eq = false;
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for (unsigned i = 0; !found_eq && i < to_app(lit)->get_num_args(); ++i) {
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expr* arg1 = to_app(lit)->get_arg(i), * arg2 = nullptr;
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rational r;
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expr_ref val = eval(arg1);
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TRACE("qe", tout << mk_pp(arg1, m) << " " << val << "\n";);
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if (!a.is_numeral(val, r)) return false;
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if (values.find(r, arg2)) {
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ty = opt::t_eq;
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linearize(mbo, eval, mul, arg1, c, fmls, ts, tids);
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linearize(mbo, eval, -mul, arg2, c, fmls, ts, tids);
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found_eq = true;
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}
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else {
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values.insert(r, arg1);
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}
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}
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SASSERT(found_eq);
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}
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else {
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TRACE("qe", tout << "Skipping " << mk_pp(lit, m) << "\n";);
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return false;
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}
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vars coeffs;
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extract_coefficients(mbo, eval, ts, tids, coeffs);
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mbo.add_constraint(coeffs, c, ty);
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return true;
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}
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//
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// convert linear arithmetic term into an inequality for mbo.
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//
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void linearize(opt::model_based_opt& mbo, model_evaluator& eval, rational const& mul, expr* t, rational& c,
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expr_ref_vector& fmls, obj_map<expr, rational>& ts, obj_map<expr, unsigned>& tids) {
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expr* t1, * t2, * t3;
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rational mul1;
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expr_ref val(m);
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auto add_def = [&](expr* t1, rational const& m, vars& coeffs) {
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obj_map<expr, rational> ts0;
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rational mul0(1), c0(0);
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linearize(mbo, eval, mul0, t1, c0, fmls, ts0, tids);
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extract_coefficients(mbo, eval, ts0, tids, coeffs);
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insert_mul(t, mul, ts);
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return c0;
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};
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if (a.is_mul(t, t1, t2) && is_numeral(t1, mul1))
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linearize(mbo, eval, mul * mul1, t2, c, fmls, ts, tids);
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else if (a.is_mul(t, t1, t2) && is_numeral(t2, mul1))
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linearize(mbo, eval, mul * mul1, t1, c, fmls, ts, tids);
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else if (a.is_uminus(t, t1))
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linearize(mbo, eval, -mul, t1, c, fmls, ts, tids);
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else if (a.is_numeral(t, mul1))
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c += mul * mul1;
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else if (a.is_add(t)) {
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for (expr* arg : *to_app(t))
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linearize(mbo, eval, mul, arg, c, fmls, ts, tids);
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}
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else if (a.is_sub(t, t1, t2)) {
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linearize(mbo, eval, mul, t1, c, fmls, ts, tids);
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linearize(mbo, eval, -mul, t2, c, fmls, ts, tids);
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}
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else if (m.is_ite(t, t1, t2, t3)) {
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val = eval(t1);
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TRACE("qe", tout << mk_pp(t1, m) << " := " << val << "\n";);
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if (m.is_true(val)) {
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linearize(mbo, eval, mul, t2, c, fmls, ts, tids);
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fmls.push_back(t1);
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}
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else if (m.is_false(val)) {
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expr_ref not_t1(mk_not(m, t1), m);
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fmls.push_back(not_t1);
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linearize(mbo, eval, mul, t3, c, fmls, ts, tids);
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}
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else {
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throw default_exception("mbp evaluation didn't produce a truth value");
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}
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}
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else if (a.is_mod(t, t1, t2) && is_numeral(t2, mul1) && mul1 > 0) {
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// v = t1 mod mul1
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vars coeffs;
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rational c0 = add_def(t1, mul1, coeffs);
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tids.insert(t, mbo.add_mod(coeffs, c0, mul1));
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}
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else if (a.is_idiv(t, t1, t2) && is_numeral(t2, mul1) && mul1 > 0) {
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// v = t1 div mul1
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vars coeffs;
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rational c0 = add_def(t1, mul1, coeffs);
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tids.insert(t, mbo.add_div(coeffs, c0, mul1));
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}
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else if (a.is_mod(t, t1, t2) && is_numeral(t2, mul1) && !mul1.is_zero()) {
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rational r;
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val = eval(t);
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if (!a.is_numeral(val, r))
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throw default_exception("mbp evaluation didn't produce an integer");
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c += mul * r;
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rational c0(-r), mul0(1);
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obj_map<expr, rational> ts0;
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linearize(mbo, eval, mul0, t1, c0, fmls, ts0, tids);
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vars coeffs;
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extract_coefficients(mbo, eval, ts0, tids, coeffs);
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mbo.add_divides(coeffs, c0, mul1);
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}
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else
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insert_mul(t, mul, ts);
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}
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bool is_numeral(expr* t, rational& r) {
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return a.is_extended_numeral(t, r);
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}
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struct compare_second {
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bool operator()(std::pair<expr*, rational> const& a,
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std::pair<expr*, rational> const& b) const {
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return a.second < b.second;
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}
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};
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bool is_arith(expr* e) {
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return a.is_int_real(e);
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}
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rational n_sign(rational const& b) {
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return rational(b.is_pos() ? -1 : 1);
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}
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bool operator()(model& model, app* v, app_ref_vector& vars, expr_ref_vector& lits) {
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app_ref_vector vs(m);
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vs.push_back(v);
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vector<def> defs;
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return project(model, vs, lits, defs, false) && vs.empty();
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}
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typedef opt::model_based_opt::var var;
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typedef opt::model_based_opt::row row;
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typedef vector<var> vars;
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expr_ref var2expr(ptr_vector<expr> const& index2expr, var const& v) {
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expr_ref t(index2expr[v.m_id], m);
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if (!v.m_coeff.is_one()) {
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t = a.mk_mul(a.mk_numeral(v.m_coeff, a.is_int(t)), t);
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}
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return t;
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}
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bool project(model& model, app_ref_vector& vars, expr_ref_vector& fmls, vector<def>& result, bool compute_def) {
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bool has_arith = false;
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for (expr* v : vars)
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has_arith |= is_arith(v);
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if (!has_arith)
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return true;
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model_evaluator eval(model);
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TRACE("qe", tout << model;);
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eval.set_model_completion(true);
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compute_def |= m_apply_projection;
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opt::model_based_opt mbo;
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obj_map<expr, unsigned> tids;
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expr_ref_vector pinned(m);
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unsigned j = 0;
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TRACE("qe", tout << "vars: " << vars << "\n";
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for (expr* f : fmls) tout << mk_pp(f, m) << " := " << model(f) << "\n";);
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for (unsigned i = 0; i < fmls.size(); ++i) {
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expr* fml = fmls.get(i);
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if (!linearize(mbo, eval, fml, fmls, tids)) {
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TRACE("qe", tout << "could not linearize: " << mk_pp(fml, m) << "\n";);
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fmls[j++] = fml;
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}
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else {
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pinned.push_back(fml);
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}
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}
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fmls.shrink(j);
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TRACE("qe", tout << "formulas\n" << fmls << "\n";
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for (auto const& [e, id] : tids)
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tout << mk_pp(e, m) << " -> " << id << "\n";);
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// fmls holds residue,
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// mbo holds linear inequalities that are in scope
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// collect variables in residue an in tids.
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// filter variables that are absent from residue.
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// project those.
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// collect result of projection
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// return those to fmls.
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expr_mark var_mark, fmls_mark;
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for (app* v : vars) {
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var_mark.mark(v);
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if (is_arith(v) && !tids.contains(v)) {
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rational r;
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expr_ref val = eval(v);
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if (!m.inc())
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return false;
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if (!a.is_numeral(val, r))
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throw default_exception("evaluation did not produce a numeral");
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TRACE("qe", tout << mk_pp(v, m) << " " << val << "\n";);
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tids.insert(v, mbo.add_var(r, a.is_int(v)));
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}
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}
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// bail on variables in non-linear sub-terms
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auto is_pure = [&](expr* e) {
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expr* x, * y;
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rational r;
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if (a.is_mod(e, x, y) && a.is_numeral(y))
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return true;
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if (a.is_idiv(e, x, y) && a.is_numeral(y, r) && r > 0)
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return true;
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return false;
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};
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for (auto& kv : tids) {
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expr* e = kv.m_key;
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if (is_arith(e) && !is_pure(e) && !var_mark.is_marked(e))
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mark_rec(fmls_mark, e);
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}
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if (m_check_purified) {
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for (expr* fml : fmls)
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mark_rec(fmls_mark, fml);
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for (auto& kv : tids) {
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expr* e = kv.m_key;
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if (!var_mark.is_marked(e) && !is_pure(e))
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mark_rec(fmls_mark, e);
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}
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}
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ptr_vector<expr> index2expr;
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for (auto& kv : tids)
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index2expr.setx(kv.m_value, kv.m_key, nullptr);
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j = 0;
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unsigned_vector real_vars;
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for (app* v : vars) {
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if (is_arith(v) && !fmls_mark.is_marked(v))
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real_vars.push_back(tids.find(v));
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else
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vars[j++] = v;
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}
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vars.shrink(j);
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TRACE("qe", tout << "remaining vars: " << vars << "\n";
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for (unsigned v : real_vars) tout << "v" << v << " " << mk_pp(index2expr[v], m) << "\n";
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mbo.display(tout););
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vector<opt::model_based_opt::def> defs = mbo.project(real_vars.size(), real_vars.data(), compute_def);
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vector<row> rows;
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mbo.get_live_rows(rows);
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rows2fmls(rows, index2expr, fmls);
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TRACE("qe", mbo.display(tout << "mbo result\n");
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for (auto const& d : defs) tout << "def: " << d << "\n";
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tout << fmls << "\n";);
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if (compute_def)
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optdefs2mbpdef(defs, index2expr, real_vars, result);
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if (m_apply_projection && !apply_projection(eval, result, fmls))
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return false;
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TRACE("qe",
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for (auto const& [v, t] : result)
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tout << v << " := " << t << "\n";
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for (auto* f : fmls)
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tout << mk_pp(f, m) << " := " << eval(f) << "\n";
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tout << "fmls:" << fmls << "\n";);
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return true;
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}
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void optdefs2mbpdef(vector<opt::model_based_opt::def> const& defs, ptr_vector<expr> const& index2expr, unsigned_vector const& real_vars, vector<def>& result) {
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SASSERT(defs.size() == real_vars.size());
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for (unsigned i = 0; i < defs.size(); ++i) {
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auto const& d = defs[i];
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expr* x = index2expr[real_vars[i]];
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bool is_int = a.is_int(x);
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expr_ref_vector ts(m);
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expr_ref t(m);
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for (var const& v : d.m_vars)
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ts.push_back(var2expr(index2expr, v));
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if (!d.m_coeff.is_zero())
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ts.push_back(a.mk_numeral(d.m_coeff, is_int));
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if (ts.empty())
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ts.push_back(a.mk_numeral(rational(0), is_int));
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t = mk_add(ts);
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if (!d.m_div.is_one() && is_int)
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t = a.mk_idiv(t, a.mk_numeral(d.m_div, is_int));
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else if (!d.m_div.is_one() && !is_int)
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t = a.mk_div(t, a.mk_numeral(d.m_div, is_int));
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result.push_back(def(expr_ref(x, m), t));
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}
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}
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expr_ref id2expr(u_map<row> const& def_vars, ptr_vector<expr> const& index2expr, unsigned id) {
|
|
row r;
|
|
if (def_vars.find(id, r))
|
|
return row2expr(def_vars, index2expr, r);
|
|
return expr_ref(index2expr[id], m);
|
|
}
|
|
|
|
expr_ref row2expr(u_map<row> const& def_vars, ptr_vector<expr> const& index2expr, row const& r) {
|
|
expr_ref_vector ts(m);
|
|
expr_ref t(m);
|
|
rational n;
|
|
for (var const& v : r.m_vars) {
|
|
t = id2expr(def_vars, index2expr, v.m_id);
|
|
if (a.is_numeral(t, n) && n == 0)
|
|
continue;
|
|
else if (a.is_numeral(t, n))
|
|
t = a.mk_numeral(v.m_coeff * n, a.is_int(t));
|
|
else if (!v.m_coeff.is_one())
|
|
t = a.mk_mul(a.mk_numeral(v.m_coeff, a.is_int(t)), t);
|
|
ts.push_back(t);
|
|
}
|
|
switch (r.m_type) {
|
|
case opt::t_mod:
|
|
if (ts.empty()) {
|
|
t = a.mk_int(mod(r.m_coeff, r.m_mod));
|
|
return t;
|
|
}
|
|
ts.push_back(a.mk_int(r.m_coeff));
|
|
t = mk_add(ts);
|
|
t = a.mk_mod(t, a.mk_int(r.m_mod));
|
|
return t;
|
|
case opt::t_div:
|
|
if (ts.empty()) {
|
|
t = a.mk_int(div(r.m_coeff, r.m_mod));
|
|
return t;
|
|
}
|
|
ts.push_back(a.mk_int(r.m_coeff));
|
|
t = mk_add(ts);
|
|
t = a.mk_idiv(t, a.mk_int(r.m_mod));
|
|
return t;
|
|
case opt::t_divides:
|
|
ts.push_back(a.mk_int(r.m_coeff));
|
|
return mk_add(ts);
|
|
default:
|
|
return mk_add(ts);
|
|
}
|
|
}
|
|
|
|
void rows2fmls(vector<row> const& rows, ptr_vector<expr> const& index2expr, expr_ref_vector& fmls) {
|
|
|
|
u_map<row> def_vars;
|
|
for (row const& r : rows) {
|
|
if (r.m_type == opt::t_mod)
|
|
def_vars.insert(r.m_id, r);
|
|
else if (r.m_type == opt::t_div)
|
|
def_vars.insert(r.m_id, r);
|
|
}
|
|
|
|
for (row const& r : rows) {
|
|
expr_ref t(m), s(m), val(m);
|
|
|
|
if (r.m_vars.empty())
|
|
continue;
|
|
if (r.m_type == opt::t_mod)
|
|
continue;
|
|
if (r.m_type == opt::t_div)
|
|
continue;
|
|
|
|
if (r.m_vars.size() == 1 && r.m_vars[0].m_coeff.is_neg() &&
|
|
(r.m_type == opt::t_eq || r.m_type == opt::t_le || r.m_type == opt::t_lt)) {
|
|
var const& v = r.m_vars[0];
|
|
t = id2expr(def_vars, index2expr, v.m_id);
|
|
if (!v.m_coeff.is_minus_one()) {
|
|
t = a.mk_mul(a.mk_numeral(-v.m_coeff, a.is_int(t)), t);
|
|
}
|
|
s = a.mk_numeral(r.m_coeff, a.is_int(t));
|
|
switch (r.m_type) {
|
|
case opt::t_lt: t = a.mk_gt(t, s); break;
|
|
case opt::t_le: t = a.mk_ge(t, s); break;
|
|
case opt::t_eq: t = a.mk_eq(t, s); break;
|
|
default: UNREACHABLE(); break;
|
|
}
|
|
fmls.push_back(t);
|
|
continue;
|
|
}
|
|
t = row2expr(def_vars, index2expr, r);
|
|
s = a.mk_numeral(-r.m_coeff, r.m_coeff.is_int() && a.is_int(t));
|
|
switch (r.m_type) {
|
|
case opt::t_lt: t = a.mk_lt(t, s); break;
|
|
case opt::t_le: t = a.mk_le(t, s); break;
|
|
case opt::t_eq: t = a.mk_eq(t, s); break;
|
|
case opt::t_divides:
|
|
t = a.mk_eq(a.mk_mod(t, a.mk_int(r.m_mod)), a.mk_int(0));
|
|
break;
|
|
default:
|
|
UNREACHABLE();
|
|
break;
|
|
}
|
|
fmls.push_back(t);
|
|
}
|
|
}
|
|
|
|
expr_ref mk_add(expr_ref_vector const& ts) {
|
|
return a.mk_add_simplify(ts);
|
|
}
|
|
|
|
opt::inf_eps maximize(expr_ref_vector const& fmls0, model& mdl, app* t, expr_ref& ge, expr_ref& gt) {
|
|
SASSERT(a.is_real(t));
|
|
expr_ref_vector fmls(fmls0);
|
|
opt::model_based_opt mbo;
|
|
opt::inf_eps value;
|
|
obj_map<expr, rational> ts;
|
|
obj_map<expr, unsigned> tids;
|
|
model_evaluator eval(mdl);
|
|
// extract objective function.
|
|
vars coeffs;
|
|
rational c(0), mul(1);
|
|
linearize(mbo, eval, mul, t, c, fmls, ts, tids);
|
|
extract_coefficients(mbo, eval, ts, tids, coeffs);
|
|
mbo.set_objective(coeffs, c);
|
|
|
|
SASSERT(validate_model(eval, fmls0));
|
|
|
|
// extract linear constraints
|
|
|
|
for (expr* fml : fmls) {
|
|
linearize(mbo, eval, fml, fmls, tids);
|
|
}
|
|
|
|
// find optimal value
|
|
value = mbo.maximize();
|
|
|
|
|
|
// update model to use new values that satisfy optimality
|
|
ptr_vector<expr> vars;
|
|
for (auto& kv : tids) {
|
|
expr* e = kv.m_key;
|
|
if (is_uninterp_const(e)) {
|
|
unsigned id = kv.m_value;
|
|
func_decl* f = to_app(e)->get_decl();
|
|
expr_ref val(a.mk_numeral(mbo.get_value(id), false), m);
|
|
mdl.register_decl(f, val);
|
|
}
|
|
else {
|
|
TRACE("qe", tout << "omitting model update for non-uninterpreted constant " << mk_pp(e, m) << "\n";);
|
|
}
|
|
}
|
|
expr_ref val(a.mk_numeral(value.get_rational(), false), m);
|
|
expr_ref tval = eval(t);
|
|
|
|
// update the predicate 'bound' which forces larger values when 'strict' is true.
|
|
// strict: bound := valuue < t
|
|
// !strict: bound := value <= t
|
|
if (!value.is_finite()) {
|
|
ge = a.mk_ge(t, tval);
|
|
gt = m.mk_false();
|
|
}
|
|
else if (value.get_infinitesimal().is_neg()) {
|
|
ge = a.mk_ge(t, tval);
|
|
gt = a.mk_ge(t, val);
|
|
}
|
|
else {
|
|
ge = a.mk_ge(t, val);
|
|
gt = a.mk_gt(t, val);
|
|
}
|
|
SASSERT(validate_model(eval, fmls0));
|
|
return value;
|
|
}
|
|
|
|
bool validate_model(model_evaluator& eval, expr_ref_vector const& fmls) {
|
|
bool valid = true;
|
|
for (expr* fml : fmls) {
|
|
expr_ref val = eval(fml);
|
|
if (!m.is_true(val)) {
|
|
valid = false;
|
|
TRACE("qe", tout << mk_pp(fml, m) << " := " << val << "\n";);
|
|
}
|
|
}
|
|
return valid;
|
|
}
|
|
|
|
void extract_coefficients(opt::model_based_opt& mbo, model_evaluator& eval, obj_map<expr, rational> const& ts, obj_map<expr, unsigned>& tids, vars& coeffs) {
|
|
coeffs.reset();
|
|
eval.set_model_completion(true);
|
|
for (auto& kv : ts) {
|
|
unsigned id;
|
|
expr* v = kv.m_key;
|
|
if (!tids.find(v, id)) {
|
|
rational r;
|
|
expr_ref val = eval(v);
|
|
if (!a.is_numeral(val, r)) {
|
|
TRACE("qe", tout << eval.get_model() << "\n";);
|
|
throw default_exception("mbp evaluation was only partial");
|
|
}
|
|
id = mbo.add_var(r, a.is_int(v));
|
|
tids.insert(v, id);
|
|
}
|
|
CTRACE("qe", kv.m_value.is_zero(), tout << mk_pp(v, m) << " has coefficeint 0\n";);
|
|
if (!kv.m_value.is_zero()) {
|
|
coeffs.push_back(var(id, kv.m_value));
|
|
}
|
|
}
|
|
}
|
|
|
|
bool apply_projection(model_evaluator& eval, vector<def> const& defs, expr_ref_vector& fmls) {
|
|
if (fmls.empty() || defs.empty())
|
|
return true;
|
|
expr_safe_replace subst(m);
|
|
expr_ref_vector fmls_tmp(m);
|
|
expr_ref tmp(m);
|
|
for (unsigned i = defs.size(); i-- > 0; ) {
|
|
auto const& d = defs[i];
|
|
subst(d.term, tmp);
|
|
subst.insert(d.var, tmp);
|
|
}
|
|
unsigned j = 0;
|
|
for (expr* fml : fmls) {
|
|
subst(fml, tmp);
|
|
if (m.is_false(eval(tmp)))
|
|
return false;
|
|
fmls[j++] = tmp;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
};
|
|
|
|
arith_project_plugin::arith_project_plugin(ast_manager& m) :project_plugin(m) {
|
|
m_imp = alloc(imp, m);
|
|
}
|
|
|
|
arith_project_plugin::~arith_project_plugin() {
|
|
dealloc(m_imp);
|
|
}
|
|
|
|
bool arith_project_plugin::operator()(model& model, app* var, app_ref_vector& vars, expr_ref_vector& lits) {
|
|
return (*m_imp)(model, var, vars, lits);
|
|
}
|
|
|
|
bool arith_project_plugin::operator()(model& model, app_ref_vector& vars, expr_ref_vector& lits) {
|
|
vector<def> defs;
|
|
return m_imp->project(model, vars, lits, defs, false);
|
|
}
|
|
|
|
bool arith_project_plugin::project(model& model, app_ref_vector& vars, expr_ref_vector& lits, vector<def>& defs) {
|
|
return m_imp->project(model, vars, lits, defs, true);
|
|
}
|
|
|
|
void arith_project_plugin::set_check_purified(bool check_purified) {
|
|
m_imp->m_check_purified = check_purified;
|
|
}
|
|
|
|
void arith_project_plugin::set_apply_projection(bool f) {
|
|
m_imp->m_apply_projection = f;
|
|
}
|
|
|
|
family_id arith_project_plugin::get_family_id() {
|
|
return m_imp->a.get_family_id();
|
|
}
|
|
|
|
opt::inf_eps arith_project_plugin::maximize(expr_ref_vector const& fmls, model& mdl, app* t, expr_ref& ge, expr_ref& gt) {
|
|
return m_imp->maximize(fmls, mdl, t, ge, gt);
|
|
}
|
|
|
|
bool arith_project(model& model, app* var, expr_ref_vector& lits) {
|
|
ast_manager& m = lits.get_manager();
|
|
arith_project_plugin ap(m);
|
|
app_ref_vector vars(m);
|
|
return ap(model, var, vars, lits);
|
|
}
|
|
}
|