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merge

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2021-11-10 03:03:23 -08:00
commit 733f44d141
151 changed files with 3249 additions and 1504 deletions
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102
src/smt/theory_seq.cpp
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@ -562,55 +562,66 @@ void theory_seq::mk_decompose(expr* e, expr_ref& head, expr_ref& tail) {
/*
\brief Check extensionality (for sequences).
*/
bool theory_seq::check_extensionality(expr* e1, enode* n1, enode* n2) {
dependency* dep = nullptr;
expr* o1 = n1->get_expr();
expr* o2 = n2->get_expr();
if (o1->get_sort() != o2->get_sort())
return true;
if (ctx.is_diseq(n1, n2) || m_exclude.contains(o1, o2))
return true;
expr_ref e2(m);
if (!canonize(n2->get_expr(), dep, e2))
return false;
m_new_eqs.reset();
bool change = false;
if (!m_seq_rewrite.reduce_eq(e1, e2, m_new_eqs, change)) {
TRACE("seq", tout << "exclude " << mk_pp(o1, m) << " " << mk_pp(o2, m) << "\n";);
m_exclude.update(o1, o2);
return true;
}
for (auto const& p : m_new_eqs) {
if (m_exclude.contains(p.first, p.second)) {
TRACE("seq", tout << "excluded " << mk_pp(p.first, m) << " " << mk_pp(p.second, m) << "\n";);
return true;
}
}
ctx.assume_eq(n1, n2);
return false;
}
bool theory_seq::check_extensionality() {
unsigned sz = get_num_vars();
unsigned_vector seqs;
dependency* dep = nullptr;
expr_ref e1(m);
for (unsigned v = 0; v < sz; ++v) {
enode* n1 = get_enode(v);
expr* o1 = n1->get_expr();
if (n1 != n1->get_root()) {
continue;
}
if (!seqs.empty() && ctx.is_relevant(n1) && m_util.is_seq(o1) && ctx.is_shared(n1)) {
dependency* dep = nullptr;
expr_ref e1(m);
if (!canonize(o1, dep, e1)) {
// check extensionality for sequence arguments of nth_u
// two occurrences of nth_u(a,x), nth_u(b,y) must induce comparing sequences a, b
// whenever x = y
if (m_util.str.is_nth_u(o1) && n1->is_cgr()) {
auto* r0 = n1->get_arg(0)->get_root();
auto* r1 = n1->get_arg(1)->get_root();
if (!canonize(r0->get_expr(), dep, e1))
return false;
}
for (theory_var v : seqs) {
enode* n2 = get_enode(v);
expr* o2 = n2->get_expr();
if (o1->get_sort() != o2->get_sort()) {
continue;
}
if (ctx.is_diseq(n1, n2) || m_exclude.contains(o1, o2)) {
continue;
}
expr_ref e2(m);
if (!canonize(n2->get_expr(), dep, e2)) {
for (auto* p : r1->get_parents())
if (p != n1 && p->is_cgr() && m_util.str.is_nth_u(p->get_expr()) &&
!check_extensionality(e1, r0, p->get_arg(0)->get_root()))
return false;
}
m_new_eqs.reset();
bool change = false;
if (!m_seq_rewrite.reduce_eq(e1, e2, m_new_eqs, change)) {
TRACE("seq", tout << "exclude " << mk_pp(o1, m) << " " << mk_pp(o2, m) << "\n";);
m_exclude.update(o1, o2);
continue;
}
bool excluded = false;
for (auto const& p : m_new_eqs) {
if (m_exclude.contains(p.first, p.second)) {
TRACE("seq", tout << "excluded " << mk_pp(p.first, m) << " " << mk_pp(p.second, m) << "\n";);
excluded = true;
break;
}
}
if (excluded) {
continue;
}
ctx.assume_eq(n1, n2);
}
if (!n1->is_root())
continue;
if (!m_util.is_seq(o1))
continue;
if (!seqs.empty() && ctx.is_relevant(n1) && ctx.is_shared(n1)) {
if (!canonize(o1, dep, e1))
return false;
}
for (theory_var v : seqs)
if (!check_extensionality(e1, n1, get_enode(v)))
return false;
}
seqs.push_back(v);
}
@ -726,7 +737,7 @@ void theory_seq::linearize(dependency* dep, enode_pair_vector& eqs, literal_vect
svector<assumption> assumptions;
const_cast<dependency_manager&>(m_dm).linearize(dep, assumptions);
for (assumption const& a : assumptions) {
if (a.lit != null_literal) {
if (a.lit != null_literal && a.lit != true_literal) {
lits.push_back(a.lit);
SASSERT(ctx.get_assignment(a.lit) == l_true);
}
@ -743,7 +754,7 @@ bool theory_seq::propagate_lit(dependency* dep, unsigned n, literal const* _lits
return false;
if (ctx.get_assignment(lit) == l_true)
return false;
literal_vector lits(n, _lits);
if (lit == false_literal) {
@ -2368,7 +2379,7 @@ void theory_seq::validate_fmls(enode_pair_vector const& eqs, literal_vector cons
theory_var theory_seq::mk_var(enode* n) {
expr* o = n->get_expr();
if (!m_util.is_seq(o) && !m_util.is_re(o))
if (!m_util.is_seq(o) && !m_util.is_re(o) && !m_util.str.is_nth_u(o))
return null_theory_var;
if (is_attached_to_var(n))
@ -2898,6 +2909,7 @@ bool theory_seq::propagate_eq(dependency* deps, literal_vector const& _lits, exp
if (n1->get_root() == n2->get_root()) {
return false;
}
ctx.mark_as_relevant(n1);
ctx.mark_as_relevant(n2);
@ -2979,8 +2991,8 @@ void theory_seq::assign_eh(bool_var v, bool is_true) {
m_rewrite(se1);
m_rewrite(se2);
if (is_true) {
expr_ref f1 = m_sk.mk_indexof_left(se1, se2);
expr_ref f2 = m_sk.mk_indexof_right(se1, se2);
expr_ref f1 = m_sk.mk_contains_left(se1, se2);
expr_ref f2 = m_sk.mk_contains_right(se1, se2);
f = mk_concat(f1, se2, f2);
propagate_eq(lit, f, e1, true);
propagate_eq(lit, mk_len(f), mk_len(e1), false);