z3-z3-4.13.0.src.ast.macros.macro_manager.cpp Maven / Gradle / Ivy
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/*++
Copyright (c) 2006 Microsoft Corporation
Module Name:
macro_manager.cpp
Abstract:
Author:
Leonardo de Moura (leonardo) 2010-04-05.
Revision History:
Christoph Wintersteiger (t-cwinte), 2010-04-13: Added cycle detection for macro definitions
Leonardo de Moura (leonardo) 2010-12-15: Moved dependency management to func_decl_dependencies.h
--*/
#include "ast/macros/macro_manager.h"
#include "ast/for_each_expr.h"
#include "ast/rewriter/var_subst.h"
#include "ast/rewriter/th_rewriter.h"
#include "ast/rewriter/rewriter_def.h"
#include "ast/ast_pp.h"
#include "ast/ast_translation.h"
#include "ast/recurse_expr_def.h"
macro_manager::macro_manager(ast_manager & m):
m(m),
m_util(m),
m_decls(m),
m_macros(m),
m_macro_prs(m),
m_macro_deps(m),
m_forbidden(m),
m_deps(m) {
m_util.set_forbidden_set(&m_forbidden_set);
}
macro_manager::~macro_manager() {
}
void macro_manager::push_scope() {
m_scopes.push_back(scope());
scope & s = m_scopes.back();
s.m_decls_lim = m_decls.size();
s.m_forbidden_lim = m_forbidden.size();
}
void macro_manager::pop_scope(unsigned num_scopes) {
unsigned new_lvl = m_scopes.size() - num_scopes;
scope & s = m_scopes[new_lvl];
restore_decls(s.m_decls_lim);
restore_forbidden(s.m_forbidden_lim);
m_scopes.shrink(new_lvl);
}
void macro_manager::restore_decls(unsigned old_sz) {
unsigned sz = m_decls.size();
for (unsigned i = old_sz; i < sz; i++) {
m_decl2macro.erase(m_decls.get(i));
m_deps.erase(m_decls.get(i));
if (m.proofs_enabled())
m_decl2macro_pr.erase(m_decls.get(i));
m_decl2macro_dep.erase(m_decls.get(i));
}
m_decls.shrink(old_sz);
m_macros.shrink(old_sz);
if (m.proofs_enabled())
m_macro_prs.shrink(old_sz);
m_macro_deps.shrink(old_sz);
}
void macro_manager::restore_forbidden(unsigned old_sz) {
unsigned sz = m_forbidden.size();
for (unsigned i = old_sz; i < sz; i++)
m_forbidden_set.erase(m_forbidden.get(i));
m_forbidden.shrink(old_sz);
}
void macro_manager::reset() {
m_decl2macro.reset();
m_decl2macro_pr.reset();
m_decl2macro_dep.reset();
m_decls.reset();
m_macros.reset();
m_macro_prs.reset();
m_macro_deps.reset();
m_scopes.reset();
m_forbidden_set.reset();
m_forbidden.reset();
m_deps.reset();
}
void macro_manager::copy_to(macro_manager& dst) {
ast_manager& tm = dst.get_manager();
ast_translation tr(m, tm);
for (func_decl* f : m_decls) {
func_decl_ref f2(tr(f), tm);
quantifier_ref q2(tr(m_decl2macro[f]), tm);
proof_ref pr2(tm);
expr_dependency_ref dep2(tm);
proof* pr1 = nullptr;
if (m_decl2macro_pr.find(f, pr1)) {
pr2 = tr(pr1);
}
expr_dependency* dep1 = m_decl2macro_dep[f];
if (dep1) {
dep2 = ::translate(dep1, m, tm);
}
dst.insert(f2, q2, pr2, dep2);
}
}
bool macro_manager::insert(func_decl * f, quantifier * q, proof * pr, expr_dependency* dep) {
TRACE("macro_insert", tout << "trying to create macro: " << f->get_name() << "\n" << mk_pp(q, m) << "\n";);
// if we already have a macro for f then return false;
if (m_decls.contains(f)) {
TRACE("macro_insert", tout << "we already have a macro for: " << f->get_name() << "\n";);
return false;
}
app * head;
expr_ref definition(m);
bool revert = false;
get_head_def(q, f, head, definition, revert);
func_decl_set * s = m_deps.mk_func_decl_set();
m_deps.collect_func_decls(definition, s);
if (!m_deps.insert(f, s)) {
return false;
}
// add macro
m_decl2macro.insert(f, q);
m_decls.push_back(f);
m_macros.push_back(q);
if (m.proofs_enabled()) {
m_macro_prs.push_back(pr);
m_decl2macro_pr.insert(f, pr);
SASSERT(m.get_fact(pr) == q);
}
m_macro_deps.push_back(dep);
m_decl2macro_dep.insert(f, dep);
TRACE("macro_insert", tout << "A macro was successfully created for: " << f->get_name() << "\n";);
// Nothing's forbidden anymore; if something's bad, we detected it earlier.
// mark_forbidden(m->get_expr());
return true;
}
namespace macro_manager_ns {
struct proc {
obj_hashtable & m_forbidden_set;
func_decl_ref_vector & m_forbidden;
proc(obj_hashtable & s, func_decl_ref_vector & v):m_forbidden_set(s), m_forbidden(v) {}
void operator()(var * n) {}
void operator()(quantifier * n) {}
void operator()(app * n) {
func_decl * d = n->get_decl();
if (n->get_num_args() > 0 && n->get_family_id() == null_family_id && !m_forbidden_set.contains(d)) {
m_forbidden_set.insert(d);
m_forbidden.push_back(d);
}
}
};
};
/**
\brief Mark all func_decls used in exprs as forbidden.
*/
void macro_manager::mark_forbidden(unsigned n, justified_expr const * exprs) {
expr_mark visited;
macro_manager_ns::proc p(m_forbidden_set, m_forbidden);
for (unsigned i = 0; i < n; i++)
for_each_expr(p, visited, exprs[i].get_fml());
}
void macro_manager::get_head_def(quantifier * q, func_decl * d, app * & head, expr_ref & def, bool& revert) const {
expr * body = q->get_expr();
expr * lhs = nullptr, *rhs = nullptr;
bool is_not = m.is_not(body, body);
VERIFY(m.is_eq(body, lhs, rhs));
SASSERT(is_app_of(lhs, d) || is_app_of(rhs, d));
SASSERT(!is_app_of(lhs, d) || !is_app_of(rhs, d));
SASSERT(!is_not || m.is_bool(lhs));
if (is_app_of(lhs, d)) {
revert = false;
head = to_app(lhs);
def = is_not ? m.mk_not(rhs) : rhs;
}
else {
revert = true;
head = to_app(rhs);
def = is_not ? m.mk_not(lhs) : lhs;
}
}
void macro_manager::display(std::ostream & out) {
unsigned sz = m_decls.size();
for (unsigned i = 0; i < sz; i++) {
func_decl * f = m_decls.get(i);
quantifier * q = nullptr;
m_decl2macro.find(f, q);
app * head;
expr_ref def(m);
bool r;
get_head_def(q, f, head, def, r);
SASSERT(q);
out << mk_pp(head, m) << " ->\n" << mk_pp(def, m) << "\n";
}
}
func_decl * macro_manager::get_macro_interpretation(unsigned i, expr_ref & interp) const {
func_decl * f = m_decls.get(i);
quantifier * q = m_macros.get(i);
app * head;
expr_ref def(m);
bool r;
get_head_def(q, f, head, def, r);
TRACE("macro_bug",
tout << f->get_name() << "\n" << mk_pp(head, m) << "\n" << mk_pp(q, m) << "\n";);
m_util.mk_macro_interpretation(head, q->get_num_decls(), def, interp);
return f;
}
struct macro_manager::macro_expander_cfg : public default_rewriter_cfg {
ast_manager& m;
macro_manager& mm;
array_util a;
expr_dependency_ref m_used_macro_dependencies;
expr_ref_vector m_trail;
macro_expander_cfg(ast_manager& m, macro_manager& mm):
m(m),
mm(mm),
a(m),
m_used_macro_dependencies(m),
m_trail(m)
{}
bool rewrite_patterns() const { return false; }
bool flat_assoc(func_decl * f) const { return false; }
br_status reduce_app(func_decl * f, unsigned num, expr * const * args, expr_ref & result, proof_ref & result_pr) {
result_pr = nullptr;
return BR_FAILED;
}
bool reduce_quantifier(quantifier * old_q,
expr * new_body,
expr * const * new_patterns,
expr * const * new_no_patterns,
expr_ref & result,
proof_ref & result_pr) {
// If a macro was expanded in a pattern, we must erase it since it may not be a valid pattern anymore.
// The MAM assumes valid patterns, and it crashes if invalid patterns are provided.
// For example, it will crash if the pattern does not contain all variables.
//
// Alternative solution: use pattern_validation to check if the pattern is still valid.
// I'm not sure if this is a good solution, since the pattern may be meaningless after the macro expansion.
// So, I'm just erasing them.
bool erase_patterns = false;
for (unsigned i = 0; !erase_patterns && i < old_q->get_num_patterns(); i++) {
if (old_q->get_pattern(i) != new_patterns[i])
erase_patterns = true;
}
for (unsigned i = 0; !erase_patterns && i < old_q->get_num_no_patterns(); i++) {
if (old_q->get_no_pattern(i) != new_no_patterns[i])
erase_patterns = true;
}
if (erase_patterns) {
result = m.update_quantifier(old_q, 0, nullptr, 0, nullptr, new_body);
}
if (erase_patterns && m.proofs_enabled()) {
result_pr = m.mk_rewrite(old_q, result);
}
return erase_patterns;
}
bool get_subst(expr * _n, expr* & r, proof* & p) {
if (!is_app(_n))
return false;
app * n = to_app(_n);
quantifier * q = nullptr;
func_decl * d = n->get_decl(), *d2 = nullptr;
TRACE("macro_manager", tout << "trying to expand:\n" << mk_pp(n, m) << "\nd:\n" << d->get_name() << "\n";);
if (mm.m_decl2macro.find(d, q)) {
app * head = nullptr;
expr_ref def(m);
bool revert = false;
mm.get_head_def(q, d, head, def, revert);
unsigned num = n->get_num_args();
SASSERT(head && def);
TRACE("macro_manager", tout << "expanding: " << mk_pp(n, m) << "\n" << mk_pp(head, m) << " " << mk_pp(def, m) << "\n";);
ptr_buffer subst_args;
subst_args.resize(num, 0);
for (unsigned i = 0; i < num; i++) {
var * v = to_var(head->get_arg(i));
if (v->get_idx() >= num)
return false;
unsigned nidx = num - v->get_idx() - 1;
SASSERT(subst_args[nidx] == 0);
subst_args[nidx] = n->get_arg(i);
}
var_subst s(m);
expr_ref rr = s(def, num, subst_args.data());
m_trail.push_back(rr);
r = rr;
if (m.proofs_enabled()) {
expr_ref instance = s(q->get_expr(), num, subst_args.data());
expr* eq, * lhs, * rhs;
if (m.is_not(instance, eq) && m.is_eq(eq, lhs, rhs)) {
if (revert)
instance = m.mk_eq(m.mk_not(lhs), rhs);
else
instance = m.mk_eq(lhs, m.mk_not(rhs));
}
SASSERT(m.is_eq(instance));
proof * qi_pr = m.mk_quant_inst(m.mk_or(m.mk_not(q), instance), num, subst_args.data());
proof * q_pr = mm.m_decl2macro_pr.find(d);
proof * prs[2] = { qi_pr, q_pr };
p = m.mk_unit_resolution(2, prs);
if (revert) p = m.mk_symmetry(p);
}
else {
p = nullptr;
}
expr_dependency * ed = mm.m_decl2macro_dep.find(d);
m_used_macro_dependencies = m.mk_join(m_used_macro_dependencies, ed);
return true;
}
else if (a.is_as_array(d, d2) && mm.m_decl2macro.find(d2, q)) {
mm.unsafe_macros().insert(d2);
}
else if (a.is_map(d, d2) && mm.m_decl2macro.find(d2, q)) {
mm.unsafe_macros().insert(d2);
}
return false;
}
};
struct macro_manager::macro_expander_rw : public rewriter_tpl {
macro_expander_cfg m_cfg;
macro_expander_rw(ast_manager& m, macro_manager& mm):
rewriter_tpl(m, m.proofs_enabled(), m_cfg),
m_cfg(m, mm)
{}
};
void macro_manager::expand_macros(expr * n, proof * pr, expr_dependency * dep, expr_ref & r, proof_ref & new_pr, expr_dependency_ref & new_dep) {
if (has_macros()) {
// Expand macros with "real" proof production support (NO rewrite*)
expr_ref old_n(m);
proof_ref old_pr(m);
expr_dependency_ref old_dep(m);
old_n = n;
old_pr = pr;
old_dep = dep;
bool change = false;
for (;;) {
macro_expander_rw proc(m, *this);
proof_ref n_eq_r_pr(m);
SASSERT(!old_pr || m.get_fact(old_pr) == old_n);
TRACE("macro_manager_bug", tout << "expand_macros:\n" << mk_pp(n, m) << "\n";);
proc(old_n, r, n_eq_r_pr);
new_pr = m.mk_modus_ponens(old_pr, n_eq_r_pr);
new_dep = m.mk_join(old_dep, proc.m_cfg.m_used_macro_dependencies);
if (r.get() == old_n.get())
break;
old_n = r;
old_pr = new_pr;
old_dep = new_dep;
change = true;
SASSERT(!new_pr || m.get_fact(new_pr) == r);
}
// apply th_rewrite to the result.
if (change) {
th_rewriter rw(m);
proof_ref rw_pr(m);
expr_ref r1(r, m);
rw(r1, r, rw_pr);
new_pr = m.mk_modus_ponens(new_pr, rw_pr);
SASSERT(!new_pr || m.get_fact(new_pr) == r);
}
}
else {
r = n;
new_pr = pr;
new_dep = dep;
}
SASSERT(!new_pr || m.get_fact(new_pr) == r);
SASSERT(!dep || new_dep);
}