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wip - testing solve-eqs2, added as tactic

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This commit is contained in:
Nikolaj Bjorner 2022-11-05 22:42:59 -07:00
parent 4d8860c0bc
commit 6c12aaad74
12 changed files with 135 additions and 60 deletions
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48
src/ast/simplifiers/solve_eqs.cpp
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@ -20,6 +20,8 @@ Author:
#include "ast/ast_util.h"
#include "ast/for_each_expr.h"
#include "ast/ast_pp.h"
#include "ast/ast_ll_pp.h"
#include "ast/occurs.h"
#include "ast/recfun_decl_plugin.h"
#include "ast/rewriter/expr_replacer.h"
#include "ast/simplifiers/solve_eqs.h"
@ -75,13 +77,15 @@ namespace euf {
auto is_safe = [&](unsigned lvl, expr* t) {
for (auto* e : subterms::all(expr_ref(t, m)))
for (auto* e : subterms::all(expr_ref(t, m), &m_todo, &m_visited))
if (is_var(e) && m_id2level[var2id(e)] < lvl)
return false;
return false;
return true;
};
unsigned init_level = UINT_MAX;
unsigned_vector todo;
for (unsigned id = 0; id < m_id2var.size(); ++id) {
if (is_explored(id))
continue;
@ -96,14 +100,16 @@ namespace euf {
todo.pop_back();
if (is_explored(j))
continue;
m_id2level[id] = curr_level++;
m_id2level[j] = curr_level++;
for (auto const& eq : m_next[j]) {
auto const& [orig, v, t, d] = eq;
SASSERT(j == var2id(v));
if (!is_safe(curr_level, t))
continue;
SASSERT(!occurs(v, t));
m_next[j][0] = eq;
m_subst_ids.push_back(id);
for (expr* e : subterms::all(expr_ref(t, m)))
m_subst_ids.push_back(j);
for (expr* e : subterms::all(expr_ref(t, m), &m_todo, &m_visited))
if (is_var(e) && !is_explored(var2id(e)))
todo.push_back(var2id(e));
break;
@ -113,19 +119,20 @@ namespace euf {
}
void solve_eqs::normalize() {
scoped_ptr<expr_replacer> rp = mk_default_expr_replacer(m, true);
scoped_ptr<expr_replacer> rp = mk_default_expr_replacer(m, false);
rp->set_substitution(m_subst.get());
std::sort(m_subst_ids.begin(), m_subst_ids.end(), [&](unsigned u, unsigned v) { return m_id2level[u] > m_id2level[v]; });
for (unsigned id : m_subst_ids) {
if (!m.inc())
break;
return;
auto const& [orig, v, def, dep] = m_next[id][0];
auto [new_def, new_dep] = rp->replace_with_dep(def);
m_stats.m_num_steps += rp->get_num_steps() + 1;
++m_stats.m_num_elim_vars;
new_dep = m.mk_join(dep, new_dep);
IF_VERBOSE(11, verbose_stream() << mk_bounded_pp(v, m) << " -> " << mk_bounded_pp(new_def, m) << "\n");
m_subst->insert(v, new_def, new_dep);
SASSERT(can_be_var(v));
// we updated the substitution, but we don't need to reset rp
@ -139,12 +146,14 @@ namespace euf {
expr* def = m_subst->find(eq.var);
tout << mk_pp(eq.var, m) << "\n----->\n" << mk_pp(def, m) << "\n\n";
});
}
void solve_eqs::apply_subst(vector<dependent_expr>& old_fmls) {
if (!m.inc())
return;
scoped_ptr<expr_replacer> rp = mk_default_expr_replacer(m, true);
scoped_ptr<expr_replacer> rp = mk_default_expr_replacer(m, false);
rp->set_substitution(m_subst.get());
for (unsigned i = m_qhead; i < m_fmls.size() && !m_fmls.inconsistent(); ++i) {
@ -152,6 +161,7 @@ namespace euf {
auto [new_f, new_dep] = rp->replace_with_dep(f);
if (new_f == f)
continue;
m_rewriter(new_f);
new_dep = m.mk_join(d, new_dep);
old_fmls.push_back(m_fmls[i]);
m_fmls.update(i, dependent_expr(m, new_f, new_dep));
@ -164,29 +174,35 @@ namespace euf {
ex->pre_process(m_fmls);
unsigned count = 0;
vector<dependent_expr> old_fmls;
dep_eq_vector eqs;
do {
vector<dependent_expr> old_fmls;
old_fmls.reset();
m_subst_ids.reset();
if (!m.inc())
return;
dep_eq_vector eqs;
eqs.reset();
get_eqs(eqs);
extract_dep_graph(eqs);
extract_subst();
normalize();
apply_subst(old_fmls);
++count;
}
while (!m_subst_ids.empty() && count < 20);
while (!m_subst_ids.empty() && count < 20 && m.inc());
if (!m.inc())
return;
save_subst({});
if (m_config.m_context_solve) {
vector<dependent_expr> old_fmls;
dep_eq_vector eqs;
if (m_config.m_context_solve) {
old_fmls.reset();
m_subst_ids.reset();
eqs.reset();
solve_context_eqs context_solve(*this);
context_solve.collect_nested_equalities(eqs);
extract_dep_graph(eqs);
extract_subst();
normalize();
apply_subst(old_fmls);
save_subst(old_fmls);
}
@ -203,7 +219,7 @@ namespace euf {
m_unsafe_vars.reset();
recfun::util rec(m);
for (func_decl* f : rec.get_rec_funs())
for (expr* term : subterms::all(expr_ref(rec.get_def(f).get_rhs(), m)))
for (expr* term : subterms::all(expr_ref(rec.get_def(f).get_rhs(), m), &m_todo, &m_visited))
m_unsafe_vars.mark(term);
}