All Downloads are FREE. Search and download functionalities are using the official Maven repository.
Many resources are needed to download a project. Please understand that we have to compensate our server costs. Thank you in advance.
Project price only 1 $
You can buy this project and download/modify it how often you want.
z3-z3-4.12.6.src.qe.mbp.mbp_basic_tg.cpp Maven / Gradle / Ivy
/*++
Copyright (c) 2022 Microsoft Corporation
Module Name:
mbp_basic_tg.cpp
Abstract:
Apply rules for model based projection for basic types, on a term graph
Author:
Hari Govind V K (hgvk94) 2023-03-07
Revision History:
--*/
#include "qe/mbp/mbp_basic_tg.h"
#include "ast/ast.h"
#include "ast/expr_functors.h"
#include "util/debug.h"
#include "util/memory_manager.h"
struct mbp_basic_tg::impl {
ast_manager &m;
mbp::term_graph &m_tg;
// TODO: cache mdl evaluation eventhough we extend m_mdl
model &m_mdl;
// set of variables on which to apply MBP rules
obj_hashtable &m_vars_set;
// variables created in the last iteration of MBP application
app_ref_vector m_new_vars;
expr_sparse_mark &m_seen;
expr_ref_vector terms;
bool m_use_mdl;
void mark_seen(expr *t) { m_seen.mark(t); }
bool is_seen(expr *t) { return m_seen.is_marked(t); }
// Split on all ite terms, irrespective of whether
// they contain variables/are c-ground
bool apply() {
std::function should_split, is_true, is_false;
if (!m_use_mdl) {
should_split = [&](expr *t) { return m_tg.has_val_in_class(t); };
is_true = [&](expr *t) {
return m_tg.has_val_in_class(t) && m_mdl.is_true(t);
};
is_false = [&](expr *t) {
return m_tg.has_val_in_class(t) && m_mdl.is_false(t);
};
} else {
should_split = [](expr *t) { return true; };
is_true = [&](expr *t) { return m_mdl.is_true(t); };
is_false = [&](expr *t) { return m_mdl.is_false(t); };
}
expr *c, *th, *el;
expr_ref nterm(m);
bool progress = false;
TRACE("mbp_tg", tout << "Iterating over terms of tg";);
// Not resetting terms because get_terms calls resize on terms
m_tg.get_terms(terms, false);
for (expr *term : terms) {
if (is_seen(term)) continue;
TRACE("mbp_tg", tout << "Processing " << expr_ref(term, m) << "\n";);
if (m.is_ite(term, c, th, el) && should_split(c)) {
mark_seen(term);
progress = true;
if (m_mdl.is_true(c)) {
m_tg.add_lit(c);
m_tg.add_eq(term, th);
} else {
nterm = mk_not(m, c);
m_tg.add_lit(nterm);
m_tg.add_eq(term, el);
}
}
if (m.is_implies(term, c, th)) {
if (is_true(th) || is_false(c)) {
mark_seen(term);
progress = true;
if (is_true(th))
m_tg.add_lit(th);
else if (is_false(c))
m_tg.add_lit(c);
m_tg.add_eq(term, m.mk_true());
} else if (is_true(c) && is_false(th)) {
mark_seen(term);
progress = true;
m_tg.add_eq(term, m.mk_false());
}
}
if (m.is_or(term) || m.is_and(term)) {
bool is_or = m.is_or(term);
app *c = to_app(term);
bool t = is_or ? any_of(*c, is_true) : all_of(*c, is_true);
bool f = is_or ? all_of(*c, is_false) : all_of(*c, is_false);
if (t || f) {
mark_seen(term);
progress = true;
m_tg.add_eq(term, t ? m.mk_true() : m.mk_false());
if (f) {
for (auto a : *c) {
if (is_false(a)) {
m_tg.add_lit(mk_not(m, a));
if (!is_or) break;
}
}
} else {
for (auto a : *c) {
if (is_true(a)) {
m_tg.add_lit(a);
if (is_or) break;
}
}
}
}
}
if (m_use_mdl && m.is_distinct(term)) {
mark_seen(term);
progress = true;
bool eq = false;
app *c = to_app(term);
for (auto a1 : *c) {
for (auto a2 : *c) {
if (a1 == a2) continue;
expr_ref e(m.mk_eq(a1, a2), m);
if (m_mdl.is_true(e)) {
m_tg.add_eq(a1, a2);
eq = true;
break;
} else {
SASSERT(m_mdl.is_false(e));
m_tg.add_deq(a1, a2);
}
}
}
if (eq)
m_tg.add_eq(term, m.mk_false());
else
m_tg.add_eq(term, m.mk_true());
}
}
return progress;
}
impl(ast_manager &man, mbp::term_graph &tg, model &mdl,
obj_hashtable &vars_set, expr_sparse_mark &seen)
: m(man), m_tg(tg), m_mdl(mdl), m_vars_set(vars_set), m_new_vars(m),
m_seen(seen), terms(m), m_use_mdl(false) {}
};
bool mbp_basic_tg::apply() { return m_impl->apply(); }
void mbp_basic_tg::use_model() { m_impl->m_use_mdl = true; }
void mbp_basic_tg::get_new_vars(app_ref_vector *&t) { t = &m_impl->m_new_vars; }
family_id mbp_basic_tg::get_family_id() const {
return m_impl->m.get_basic_family_id();
}
mbp_basic_tg::mbp_basic_tg(ast_manager &man, mbp::term_graph &tg, model &mdl,
obj_hashtable &vars_set,
expr_sparse_mark &seen) {
m_impl = alloc(mbp_basic_tg::impl, man, tg, mdl, vars_set, seen);
}
mbp_basic_tg::~mbp_basic_tg() { dealloc(m_impl); }
