mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-04-29 20:05:51 +00:00
Code Activity

seq

Browse source 
Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2015-12-10 19:20:16 -08:00
parent 30580a012a
commit 5eb23e1e7a
17 changed files with 287 additions and 141 deletions
Download patch file Download diff file Expand all files Collapse all files

112
src/smt/theory_seq.cpp
View file

@ -136,12 +136,12 @@ theory_seq::theory_seq(ast_manager& m):
m_lhs.push_back(expr_array());
m_rhs.push_back(expr_array());
m_deps.push_back(enode_pair_dependency_array());
m_prefix_sym = "prefix";
m_suffix_sym = "suffix";
m_left_sym = "left";
m_right_sym = "right";
m_contains_left_sym = "contains_left";
m_contains_right_sym = "contains_right";
m_prefix_sym = "seq.prefix.suffix";
m_suffix_sym = "seq.suffix.prefix";
m_left_sym = "seq.left";
m_right_sym = "seq.right";
m_contains_left_sym = "seq.contains.left";
m_contains_right_sym = "seq.contains.right";
}
theory_seq::~theory_seq() {
@ -261,17 +261,19 @@ bool theory_seq::find_branch_candidate(expr* l, ptr_vector<expr> const& rs) {
}
bool theory_seq::assume_equality(expr* l, expr* r) {
TRACE("seq", tout << mk_pp(l, m) << " = " << mk_pp(r, m) << "\n";);
context& ctx = get_context();
if (m_exclude.contains(l, r)) {
return false;
}
else {
SASSERT(ctx.e_internalized(l));
TRACE("seq", tout << mk_pp(l, m) << " = " << mk_pp(r, m) << "\n";);
if (!ctx.e_internalized(l)) ctx.internalize(l, false);
if (!ctx.e_internalized(r)) ctx.internalize(r, false);
ctx.assume_eq(ctx.get_enode(l), ctx.get_enode(r));
ctx.mark_as_relevant(ctx.get_enode(l));
ctx.mark_as_relevant(ctx.get_enode(r));
ctx.assume_eq(ctx.get_enode(l), ctx.get_enode(r));
return true;
}
return true;
}
bool theory_seq::split_variable() {
@ -519,26 +521,37 @@ void theory_seq::apply_sort_cnstr(enode* n, sort* s) {
}
void theory_seq::display(std::ostream & out) const {
display_equations(out);
if (m.size(m_lhs.back()) == 0 &&
m_ineqs.empty() &&
m_rep.empty() &&
m_exclude.empty()) {
return;
}
out << "Theory seq\n";
if (m.size(m_lhs.back()) > 0) {
out << "Equations:\n";
display_equations(out);
}
if (!m_ineqs.empty()) {
out << "Negative constraints:\n";
for (unsigned i = 0; i < m_ineqs.size(); ++i) {
out << mk_pp(m_ineqs[i], m) << "\n";
}
}
out << "Solved equations:\n";
m_rep.display(out);
m_exclude.display(out);
if (!m_rep.empty()) {
out << "Solved equations:\n";
m_rep.display(out);
}
if (!m_exclude.empty()) {
out << "Exclusions:\n";
m_exclude.display(out);
}
}
void theory_seq::display_equations(std::ostream& out) const {
expr_array const& lhs = m_lhs.back();
expr_array const& rhs = m_rhs.back();
enode_pair_dependency_array const& deps = m_deps.back();
if (m.size(lhs) == 0) {
return;
}
out << "Equations:\n";
for (unsigned i = 0; i < m.size(lhs); ++i) {
out << mk_pp(m.get(lhs, i), m) << " = " << mk_pp(m.get(rhs, i), m) << " <-\n";
display_deps(out, m_dam.get(deps, i));
@ -585,6 +598,10 @@ void theory_seq::set_incomplete(app* term) {
}
theory_var theory_seq::mk_var(enode* n) {
if (!m_util.is_seq(n->get_owner()) ||
!m_util.is_re(n->get_owner())) {
return null_theory_var;
}
if (is_attached_to_var(n)) {
return n->get_th_var(get_id());
}
@ -658,6 +675,7 @@ void theory_seq::propagate() {
}
void theory_seq::enque_axiom(expr* e) {
TRACE("seq", tout << "add axioms for: " << mk_pp(e, m) << "\n";);
m_trail_stack.push(push_back_vector<theory_seq, expr_ref_vector>(m_axioms));
m_axioms.push_back(e);
}
@ -732,8 +750,8 @@ void theory_seq::new_eq_len_concat(enode* n1, enode* n2) {
lit or s = "" or !prefix(s, x*s1)
*/
void theory_seq::tightest_prefix(expr* s, expr* x, literal lit) {
expr_ref s1 = mk_skolem(symbol("first"), s);
expr_ref c = mk_skolem(symbol("last"), s);
expr_ref s1 = mk_skolem(symbol("seq.first"), s);
expr_ref c = mk_skolem(symbol("seq.last"), s);
expr_ref s1c(m_util.str.mk_concat(s1, c), m);
expr_ref lc(m_util.str.mk_length(c), m);
expr_ref one(m_autil.mk_int(1), m);
@ -745,13 +763,13 @@ void theory_seq::tightest_prefix(expr* s, expr* x, literal lit) {
}
/*
let i = Index(s, t, offset)
let i = Index(t, s, offset)
if offset = 0:
(!contains(s, t) -> i = -1)
(!contains(t, s) -> i = -1)
(s = empty -> i = 0)
(contains(s, t) & s != empty -> t = xsy)
(contains(s, t) -> tightest_prefix(s, x))
(contains(t, s) & s != empty -> t = xsy)
(contains(t, s) -> tightest_prefix(s, x))
if 0 <= offset < len(t):
t = zt' & len(z) == offset
add above constraints with t'
@ -767,16 +785,16 @@ void theory_seq::tightest_prefix(expr* s, expr* x, literal lit) {
void theory_seq::add_indexof_axiom(expr* i) {
expr* s, *t, *offset;
rational r;
VERIFY(m_util.str.is_index(i, s, t, offset));
VERIFY(m_util.str.is_index(i, t, s, offset));
expr_ref emp(m), minus_one(m), zero(m), xsy(m);
minus_one = m_autil.mk_int(-1);
zero = m_autil.mk_int(0);
emp = m_util.str.mk_empty(m.get_sort(s));
if (m_autil.is_numeral(offset, r) && r.is_zero()) {
expr_ref x = mk_skolem(m_contains_left_sym, s, t);
expr_ref y = mk_skolem(m_contains_right_sym, s, t);
expr_ref x = mk_skolem(m_contains_left_sym, t, s);
expr_ref y = mk_skolem(m_contains_right_sym, t, s);
xsy = m_util.str.mk_concat(x,s,y);
literal cnt = mk_literal(m_util.str.mk_contains(s, t));
literal cnt = mk_literal(m_util.str.mk_contains(t, s));
literal eq_empty = mk_eq(s, emp, false);
add_axiom(cnt, mk_eq(i, minus_one, false));
add_axiom(~eq_empty, mk_eq(i, zero, false));
@ -791,19 +809,19 @@ void theory_seq::add_indexof_axiom(expr* i) {
/*
let r = replace(a, s, t)
(contains(s, a) -> tightest_prefix(s,xs))
(contains(s, a) -> r = xty & a = xsy) &
(!contains(s, a) -> r = a)
(contains(a, s) -> tightest_prefix(s,xs))
(contains(a, s) -> r = xty & a = xsy) &
(!contains(a, s) -> r = a)
*/
void theory_seq::add_replace_axiom(expr* r) {
expr* a, *s, *t;
VERIFY(m_util.str.is_replace(r, a, s, t));
expr_ref x = mk_skolem(m_contains_left_sym, s, a);
expr_ref y = mk_skolem(m_contains_right_sym, s, a);
expr_ref x = mk_skolem(m_contains_left_sym, a, s);
expr_ref y = mk_skolem(m_contains_right_sym, a, s);
expr_ref xty(m_util.str.mk_concat(x, t, y), m);
expr_ref xsy(m_util.str.mk_concat(x, s, y), m);
literal cnt = mk_literal(m_util.str.mk_contains(s, a));
literal cnt = mk_literal(m_util.str.mk_contains(a ,s));
add_axiom(cnt, mk_eq(r, a, false));
add_axiom(~cnt, mk_eq(a, xsy, false));
add_axiom(~cnt, mk_eq(r, xty, false));
@ -871,7 +889,7 @@ expr* theory_seq::mk_sub(expr* a, expr* b) {
void theory_seq::add_extract_axiom(expr* e) {
expr* s, *i, *l;
VERIFY(m_util.str.is_extract(e, s, i, l));
expr_ref x(mk_skolem(symbol("extract_prefix"), s, e), m);
expr_ref x(mk_skolem(symbol("seq.extract.prefix"), s, e), m);
expr_ref ls(m_util.str.mk_length(s), m);
expr_ref lx(m_util.str.mk_length(x), m);
expr_ref le(m_util.str.mk_length(e), m);
@ -901,8 +919,8 @@ void theory_seq::add_at_axiom(expr* e) {
expr* s, *i;
VERIFY(m_util.str.is_at(e, s, i));
expr_ref x(m), y(m), lx(m), le(m), xey(m), zero(m), one(m), len_e(m), len_x(m);
x = mk_skolem(symbol("at_left"), s);
y = mk_skolem(symbol("at_right"), s);
x = mk_skolem(symbol("seq.at.left"), s);
y = mk_skolem(symbol("seq.at.right"), s);
xey = m_util.str.mk_concat(x, e, y);
zero = m_autil.mk_int(0);
one = m_autil.mk_int(1);
@ -928,10 +946,10 @@ literal theory_seq::mk_literal(expr* _e) {
void theory_seq::add_axiom(literal l1, literal l2, literal l3, literal l4) {
context& ctx = get_context();
literal_vector lits;
if (l1 != null_literal) lits.push_back(l1);
if (l2 != null_literal) lits.push_back(l2);
if (l3 != null_literal) lits.push_back(l3);
if (l4 != null_literal) lits.push_back(l4);
if (l1 != null_literal) { ctx.mark_as_relevant(l1); lits.push_back(l1); }
if (l2 != null_literal) { ctx.mark_as_relevant(l2); lits.push_back(l2); }
if (l3 != null_literal) { ctx.mark_as_relevant(l3); lits.push_back(l3); }
if (l4 != null_literal) { ctx.mark_as_relevant(l4); lits.push_back(l4); }
TRACE("seq", ctx.display_literals_verbose(tout, lits.size(), lits.c_ptr()); tout << "\n";);
ctx.mk_th_axiom(get_id(), lits.size(), lits.c_ptr());
}
@ -981,11 +999,11 @@ void theory_seq::assign_eq(bool_var v, bool is_true) {
else if (m_util.str.is_contains(e, e1, e2)) {
expr_ref f1 = mk_skolem(m_contains_left_sym, e1, e2);
expr_ref f2 = mk_skolem(m_contains_right_sym, e1, e2);
f = m_util.str.mk_concat(m_util.str.mk_concat(f1, e1), f2);
propagate_eq(v, f, e2);
f = m_util.str.mk_concat(m_util.str.mk_concat(f1, e2), f2);
propagate_eq(v, f, e1);
}
else if (m_util.str.is_in_re(e, e1, e2)) {
NOT_IMPLEMENTED_YET();
// TBD
}
else {
UNREACHABLE();
@ -1001,8 +1019,10 @@ void theory_seq::new_eq_eh(theory_var v1, theory_var v2) {
enode* n1 = get_enode(v1);
enode* n2 = get_enode(v2);
if (n1 != n2) {
m.push_back(m_lhs.back(), n1->get_owner());
m.push_back(m_rhs.back(), n2->get_owner());
expr* o1 = n1->get_owner(), *o2 = n2->get_owner();
TRACE("seq", tout << mk_pp(o1, m) << " = " << mk_pp(o2, m) << "\n";);
m.push_back(m_lhs.back(), o1);
m.push_back(m_rhs.back(), o2);
m_dam.push_back(m_deps.back(), m_dm.mk_leaf(enode_pair(n1, n2)));
new_eq_len_concat(n1, n2);