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State graph dgml update and fixes in condition simplifier (#5721)

Browse source 
* improved generated dgml graph

* fixed simplification of negated ranges and did some code cleanup

* do not make loops with lower=upper=0, this is epsilon

* do not add loops with lower=upper=1

* bug fix in normalization: forgotten eps case
This commit is contained in:
Margus Veanes 2021-12-19 11:09:55 -08:00 committed by GitHub
parent bee742111a
commit a7b1db611c
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GPG key ID: 4AEE18F83AFDEB23
5 changed files with 168 additions and 220 deletions
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295
src/ast/rewriter/seq_rewriter.cpp
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@ -2857,7 +2857,7 @@ br_status seq_rewriter::mk_re_reverse(expr* r, expr_ref& result) {
return BR_REWRITE2; return BR_REWRITE2;
} }
else if (re().is_loop(r, r1, lo, hi)) { else if (re().is_loop(r, r1, lo, hi)) {
result = re().mk_loop(re().mk_reverse(r1), lo, hi); result = re().mk_loop_proper(re().mk_reverse(r1), lo, hi);
return BR_REWRITE2; return BR_REWRITE2;
} }
else if (re().is_reverse(r, r1)) { else if (re().is_reverse(r, r1)) {
@ -3184,7 +3184,7 @@ void seq_rewriter::mk_antimirov_deriv_rec(expr* e, expr* r, expr* path, expr_ref
if ((lo == 0 && hi == 0) || hi < lo) if ((lo == 0 && hi == 0) || hi < lo)
result = nothing(); result = nothing();
else else
result = mk_antimirov_deriv_concat(mk_antimirov_deriv(e, r1, path), re().mk_loop(r1, (lo == 0 ? 0 : lo - 1), hi - 1)); result = mk_antimirov_deriv_concat(mk_antimirov_deriv(e, r1, path), re().mk_loop_proper(r1, (lo == 0 ? 0 : lo - 1), hi - 1));
} }
else if (re().is_opt(r, r1)) else if (re().is_opt(r, r1))
result = mk_antimirov_deriv(e, r1, path); result = mk_antimirov_deriv(e, r1, path);
@ -3350,6 +3350,8 @@ expr_ref seq_rewriter::mk_regex_inter_normalize(expr* r1, expr* r2) {
SASSERT(m_util.is_re(r1)); SASSERT(m_util.is_re(r1));
SASSERT(m_util.is_re(r2)); SASSERT(m_util.is_re(r2));
expr_ref result(m()); expr_ref result(m());
if (re().is_epsilon(r2))
std::swap(r1, r2);
std::function<bool(expr*, expr*&, expr*&)> test = [&](expr* t, expr*& a, expr*& b) { return re().is_intersection(t, a, b); }; std::function<bool(expr*, expr*&, expr*&)> test = [&](expr* t, expr*& a, expr*& b) { return re().is_intersection(t, a, b); };
std::function<expr* (expr*, expr*)> compose = [&](expr* r1, expr* r2) { return re().mk_inter(r1, r2); }; std::function<expr* (expr*, expr*)> compose = [&](expr* r1, expr* r2) { return re().mk_inter(r1, r2); };
if (r1 == r2 || re().is_empty(r1) || re().is_full_seq(r2)) if (r1 == r2 || re().is_empty(r1) || re().is_full_seq(r2))
@ -3504,7 +3506,7 @@ expr_ref seq_rewriter::mk_regex_reverse(expr* r) {
else if (re().is_loop(r, r1, lo)) else if (re().is_loop(r, r1, lo))
result = re().mk_loop(mk_regex_reverse(r1), lo); result = re().mk_loop(mk_regex_reverse(r1), lo);
else if (re().is_loop(r, r1, lo, hi)) else if (re().is_loop(r, r1, lo, hi))
result = re().mk_loop(mk_regex_reverse(r1), lo, hi); result = re().mk_loop_proper(mk_regex_reverse(r1), lo, hi);
else if (re().is_opt(r, r1)) else if (re().is_opt(r, r1))
result = re().mk_opt(mk_regex_reverse(r1)); result = re().mk_opt(mk_regex_reverse(r1));
else if (re().is_complement(r, r1)) else if (re().is_complement(r, r1))
@ -3517,8 +3519,9 @@ expr_ref seq_rewriter::mk_regex_reverse(expr* r) {
} }
expr_ref seq_rewriter::mk_regex_concat(expr* r, expr* s) { expr_ref seq_rewriter::mk_regex_concat(expr* r, expr* s) {
sort* seq_sort = nullptr; sort* seq_sort = nullptr, * ele_sort = nullptr;
VERIFY(m_util.is_re(r, seq_sort)); VERIFY(m_util.is_re(r, seq_sort));
VERIFY(u().is_seq(seq_sort, ele_sort));
SASSERT(r->get_sort() == s->get_sort()); SASSERT(r->get_sort() == s->get_sort());
expr_ref result(m()); expr_ref result(m());
expr* r1, * r2; expr* r1, * r2;
@ -3528,11 +3531,30 @@ expr_ref seq_rewriter::mk_regex_concat(expr* r, expr* s) {
result = r; result = r;
else if (re().is_full_seq(r) && re().is_full_seq(s)) else if (re().is_full_seq(r) && re().is_full_seq(s))
result = r; result = r;
else if (re().is_full_char(r) && re().is_full_seq(s))
// ..* = .+
result = re().mk_plus(re().mk_full_char(ele_sort));
else if (re().is_full_seq(r) && re().is_full_char(s))
// .*. = .+
result = re().mk_plus(re().mk_full_char(ele_sort));
else if (re().is_concat(r, r1, r2)) else if (re().is_concat(r, r1, r2))
//create the resulting concatenation in right-associative form // create the resulting concatenation in right-associative form except for the following case
// TODO: maintain the followig invariant for A ++ B{m,n} + C
// concat(concat(A, B{m,n}), C) (if A != () and C != ())
// concat(B{m,n}, C) (if A == () and C != ())
// where A, B, C are regexes
// Using & below for Intersection and | for Union
// In other words, do not make A ++ B{m,n} into right-assoc form, but keep B{m,n} at the top
// This will help to identify this situation in the merge routine:
// concat(concat(A, B{0,m}), C) | concat(concat(A, B{0,n}), C)
// simplies to
// concat(concat(A, B{0,max(m,n)}), C)
// analogously:
// concat(concat(A, B{0,m}), C) & concat(concat(A, B{0,n}), C)
// simplies to
// concat(concat(A, B{0,min(m,n)}), C)
result = mk_regex_concat(r1, mk_regex_concat(r2, s)); result = mk_regex_concat(r1, mk_regex_concat(r2, s));
else { else {
//TODO: perhaps simplifiy some further cases such as .*. = ..* = .*.+ = .+.* = .+
result = re().mk_concat(r, s); result = re().mk_concat(r, s);
} }
return result; return result;
@ -3566,15 +3588,7 @@ expr_ref seq_rewriter::mk_in_antimirov_rec(expr* s, expr* d) {
*/ */
expr_ref seq_rewriter::simplify_path(expr* elem, expr* path) { expr_ref seq_rewriter::simplify_path(expr* elem, expr* path) {
expr_ref result(path, m()); expr_ref result(path, m());
expr* h = nullptr, * t = nullptr; elim_condition(elem, result);
if (m().is_and(path, h, t)) {
if (m().is_true(h))
result = simplify_path(elem, t);
else if (m().is_true(t))
result = simplify_path(elem, h);
else
elim_condition(elem, result);
}
return result; return result;
} }
@ -4027,7 +4041,7 @@ expr_ref seq_rewriter::mk_derivative_rec(expr* ele, expr* r) {
return result; return result;
} }
else { else {
return mk_der_concat(result, re().mk_loop(r1, lo, hi)); return mk_der_concat(result, re().mk_loop_proper(r1, lo, hi));
} }
} }
else if (re().is_full_seq(r) || else if (re().is_full_seq(r) ||
@ -4523,7 +4537,7 @@ br_status seq_rewriter::mk_re_concat(expr* a, expr* b, expr_ref& result) {
unsigned lo1, hi1, lo2, hi2; unsigned lo1, hi1, lo2, hi2;
if (re().is_loop(a, a1, lo1, hi1) && lo1 <= hi1 && re().is_loop(b, b1, lo2, hi2) && lo2 <= hi2 && a1 == b1) { if (re().is_loop(a, a1, lo1, hi1) && lo1 <= hi1 && re().is_loop(b, b1, lo2, hi2) && lo2 <= hi2 && a1 == b1) {
result = re().mk_loop(a1, lo1 + lo2, hi1 + hi2); result = re().mk_loop_proper(a1, lo1 + lo2, hi1 + hi2);
return BR_DONE; return BR_DONE;
} }
if (re().is_loop(a, a1, lo1) && re().is_loop(b, b1, lo2) && a1 == b1) { if (re().is_loop(a, a1, lo1) && re().is_loop(b, b1, lo2) && a1 == b1) {
@ -4631,79 +4645,13 @@ br_status seq_rewriter::mk_re_union0(expr* a, expr* b, expr_ref& result) {
return BR_FAILED; return BR_FAILED;
} }
/* /* Creates a normalized union. */
(a + a) = a
(a + eps) = a
(eps + a) = a
*/
br_status seq_rewriter::mk_re_union(expr* a, expr* b, expr_ref& result) { br_status seq_rewriter::mk_re_union(expr* a, expr* b, expr_ref& result) {
br_status st = mk_re_union0(a, b, result);
if (st != BR_FAILED)
return st;
auto mk_full = [&]() { return re().mk_full_seq(a->get_sort()); };
if (are_complements(a, b)) {
result = mk_full();
return BR_DONE;
}
//just keep the union normalized
result = mk_regex_union_normalize(a, b); result = mk_regex_union_normalize(a, b);
return BR_DONE; return BR_DONE;
expr* a1 = nullptr, *a2 = nullptr;
expr* b1 = nullptr, *b2 = nullptr;
// ensure union is right-associative
// and swap-sort entries
if (re().is_union(a, a1, a2)) {
result = re().mk_union(a1, re().mk_union(a2, b));
return BR_REWRITE2;
}
auto get_id = [&](expr* e) { re().is_complement(e, e); return e->get_id(); };
if (re().is_union(b, b1, b2)) {
if (is_subset(a, b1)) {
result = b;
return BR_DONE;
}
if (is_subset(b1, a)) {
result = re().mk_union(a, b2);
return BR_REWRITE1;
}
if (are_complements(a, b1)) {
result = mk_full();
return BR_DONE;
}
if (get_id(a) > get_id(b1)) {
result = re().mk_union(b1, re().mk_union(a, b2));
return BR_REWRITE2;
}
}
else {
if (is_subset(a, b)) {
result = b;
return BR_DONE;
}
if (is_subset(b, a)) {
result = a;
return BR_DONE;
}
if (get_id(a) > get_id(b)) {
result = re().mk_union(b, a);
return BR_DONE;
}
}
return BR_FAILED;
} }
/* /* Creates a normalized complement */
comp(intersect e1 e2) -> union comp(e1) comp(e2)
comp(union e1 e2) -> intersect comp(e1) comp(e2)
comp(none) -> all
comp(all) -> none
comp(comp(e1)) -> e1
comp(epsilon) -> .+
*/
br_status seq_rewriter::mk_re_complement(expr* a, expr_ref& result) { br_status seq_rewriter::mk_re_complement(expr* a, expr_ref& result) {
expr *e1 = nullptr, *e2 = nullptr; expr *e1 = nullptr, *e2 = nullptr;
if (re().is_intersection(a, e1, e2)) { if (re().is_intersection(a, e1, e2)) {
@ -4758,84 +4706,10 @@ br_status seq_rewriter::mk_re_inter0(expr* a, expr* b, expr_ref& result) {
return BR_FAILED; return BR_FAILED;
} }
/** /* Creates a normalized intersection. */
(r n r) = r
(emp n r) = emp
(r n emp) = emp
(all n r) = r
(r n all) = r
(r n comp(r)) = emp
(comp(r) n r) = emp
(r n to_re(s)) = ite (s in r) to_re(s) emp
(to_re(s) n r) = "
*/
br_status seq_rewriter::mk_re_inter(expr* a, expr* b, expr_ref& result) { br_status seq_rewriter::mk_re_inter(expr* a, expr* b, expr_ref& result) {
br_status st = mk_re_inter0(a, b, result);
if (st != BR_FAILED)
return st;
auto mk_empty = [&]() { return re().mk_empty(a->get_sort()); };
if (are_complements(a, b)) {
result = mk_empty();
return BR_DONE;
}
// intersect and normalize
result = mk_regex_inter_normalize(a, b); result = mk_regex_inter_normalize(a, b);
return BR_DONE; return BR_DONE;
expr* a1 = nullptr, *a2 = nullptr;
expr* b1 = nullptr, *b2 = nullptr;
// the following rewrite rules do not seem to
// do the right thing when it comes to normalizing
// ensure intersection is right-associative
// and swap-sort entries
if (re().is_intersection(a, a1, a2)) {
result = re().mk_inter(a1, re().mk_inter(a2, b));
return BR_REWRITE2;
}
auto get_id = [&](expr* e) { re().is_complement(e, e); return e->get_id(); };
if (re().is_intersection(b, b1, b2)) {
if (is_subset(b1, a)) {
result = b;
return BR_DONE;
}
if (is_subset(a, b1)) {
result = re().mk_inter(a, b2);
return BR_REWRITE1;
}
if (are_complements(a, b1)) {
result = mk_empty();
return BR_DONE;
}
if (get_id(a) > get_id(b1)) {
result = re().mk_inter(b1, re().mk_inter(a, b2));
return BR_REWRITE2;
}
}
else {
if (get_id(a) > get_id(b)) {
result = re().mk_inter(b, a);
return BR_DONE;
}
if (is_subset(a, b)) {
result = a;
return BR_DONE;
}
if (is_subset(b, a)) {
result = b;
return BR_DONE;
}
}
if (re().is_to_re(b))
std::swap(a, b);
expr* s = nullptr;
if (re().is_to_re(a, s)) {
result = m().mk_ite(re().mk_in_re(s, b), a, re().mk_empty(a->get_sort()));
return BR_REWRITE2;
}
return BR_FAILED;
} }
br_status seq_rewriter::mk_re_diff(expr* a, expr* b, expr_ref& result) { br_status seq_rewriter::mk_re_diff(expr* a, expr* b, expr_ref& result) {
@ -4873,7 +4747,7 @@ br_status seq_rewriter::mk_re_loop(func_decl* f, unsigned num_args, expr* const*
} }
// (loop (loop a l l) h h) = (loop a l*h l*h) // (loop (loop a l l) h h) = (loop a l*h l*h)
if (re().is_loop(args[0], a, lo, hi) && np == 2 && lo == hi && lo2 == hi2) { if (re().is_loop(args[0], a, lo, hi) && np == 2 && lo == hi && lo2 == hi2) {
result = re().mk_loop(a, lo2 * lo, hi2 * hi); result = re().mk_loop_proper(a, lo2 * lo, hi2 * hi);
return BR_REWRITE1; return BR_REWRITE1;
} }
// (loop a 1 1) = a // (loop a 1 1) = a
@ -4900,7 +4774,7 @@ br_status seq_rewriter::mk_re_loop(func_decl* f, unsigned num_args, expr* const*
case 3: case 3:
if (m_autil.is_numeral(args[1], n1) && n1.is_unsigned() && if (m_autil.is_numeral(args[1], n1) && n1.is_unsigned() &&
m_autil.is_numeral(args[2], n2) && n2.is_unsigned()) { m_autil.is_numeral(args[2], n2) && n2.is_unsigned()) {
result = re().mk_loop(args[0], n1.get_unsigned(), n2.get_unsigned()); result = re().mk_loop_proper(args[0], n1.get_unsigned(), n2.get_unsigned());
return BR_REWRITE1; return BR_REWRITE1;
} }
break; break;
@ -4912,7 +4786,7 @@ br_status seq_rewriter::mk_re_loop(func_decl* f, unsigned num_args, expr* const*
br_status seq_rewriter::mk_re_power(func_decl* f, expr* a, expr_ref& result) { br_status seq_rewriter::mk_re_power(func_decl* f, expr* a, expr_ref& result) {
unsigned p = f->get_parameter(0).get_int(); unsigned p = f->get_parameter(0).get_int();
result = re().mk_loop(a, p, p); result = re().mk_loop_proper(a, p, p);
return BR_REWRITE1; return BR_REWRITE1;
} }
@ -5079,74 +4953,67 @@ void seq_rewriter::intersect(unsigned lo, unsigned hi, svector<std::pair<unsigne
*/ */
void seq_rewriter::elim_condition(expr* elem, expr_ref& cond) { void seq_rewriter::elim_condition(expr* elem, expr_ref& cond) {
expr_ref_vector conds(m()); expr_ref_vector conds(m());
expr_ref_vector conds_range(m());
flatten_and(cond, conds); flatten_and(cond, conds);
expr* lhs = nullptr, *rhs = nullptr, *e1 = nullptr; expr* lhs = nullptr, *rhs = nullptr, *e1 = nullptr;
if (u().is_char(elem)) { if (u().is_char(elem)) {
unsigned ch = 0, ch2 = 0; unsigned ch = 0, ch2 = 0;
svector<std::pair<unsigned, unsigned>> ranges, ranges1; svector<std::pair<unsigned, unsigned>> ranges, ranges1;
ranges.push_back(std::make_pair(0, u().max_char())); ranges.push_back(std::make_pair(0, u().max_char()));
auto exclude_char = [&](unsigned ch) { auto exclude_range = [&](unsigned lower, unsigned upper) {
if (ch == 0) { SASSERT(lower <= upper);
intersect(1, u().max_char(), ranges); if (lower == 0) {
} if (upper == u().max_char())
else if (ch == u().max_char()) { ranges.reset();
intersect(0, ch-1, ranges); else
intersect(upper + 1, u().max_char(), ranges);
} }
else if (upper == u().max_char())
intersect(0, lower - 1, ranges);
else { else {
// not(lower <= e <= upper) iff ((0 <= e <= lower-1) or (upper+1 <= e <= max))
// Note that this transformation is correct only when lower <= upper
ranges1.reset(); ranges1.reset();
ranges1.append(ranges); ranges1.append(ranges);
intersect(0, ch - 1, ranges); intersect(0, lower - 1, ranges);
intersect(ch + 1, u().max_char(), ranges1); intersect(upper + 1, u().max_char(), ranges1);
ranges.append(ranges1); ranges.append(ranges1);
} }
}; };
bool all_ranges = true; bool all_ranges = true;
bool negated = false;
for (expr* e : conds) { for (expr* e : conds) {
if (m().is_eq(e, lhs, rhs) && elem == lhs && u().is_const_char(rhs, ch)) { if (u().is_char_const_range(elem, e, ch, ch2, negated)) {
intersect(ch, ch, ranges); if (ch > ch2) {
if (negated)
// !(ch <= elem <= ch2) is trivially true
continue;
else
// (ch <= elem <= ch2) is trivially false
ranges.reset();
}
else if (negated)
exclude_range(ch, ch2);
else
intersect(ch, ch2, ranges);
conds_range.push_back(e);
} }
else if (m().is_eq(e, lhs, rhs) && elem == rhs && u().is_const_char(lhs, ch)) { // trivially true conditions
intersect(ch, ch, ranges); else if (m().is_true(e) || (m().is_eq(e, lhs, rhs) && lhs == rhs))
}
else if (u().is_char_le(e, lhs, rhs) && elem == lhs && u().is_const_char(rhs, ch)) {
intersect(0, ch, ranges);
}
else if (u().is_char_le(e, lhs, rhs) && elem == rhs && u().is_const_char(lhs, ch)) {
intersect(ch, u().max_char(), ranges);
}
else if (m().is_not(e, e1) && m().is_eq(e1, lhs, rhs) && elem == lhs && u().is_const_char(rhs, ch)) {
exclude_char(ch);
}
else if (m().is_not(e, e1) && m().is_eq(e1, lhs, rhs) && elem == rhs && u().is_const_char(lhs, ch)) {
exclude_char(ch);
}
else if (m().is_not(e, e1) && u().is_char_le(e1, lhs, rhs) && elem == lhs && u().is_const_char(rhs, ch)) {
// not (e <= ch)
if (ch == u().max_char())
ranges.reset();
else
intersect(ch+1, u().max_char(), ranges);
}
else if (m().is_not(e, e1) && u().is_char_le(e1, lhs, rhs) && elem == rhs && u().is_const_char(lhs, ch)) {
// not (ch <= e)
if (ch == 0)
ranges.reset();
else
intersect(0, ch-1, ranges);
}
else if (m().is_true(e) || (m().is_eq(e, lhs, rhs) && lhs == rhs)) {
// trivially true
continue; continue;
} else if (m().is_not(e, e1) && m().is_eq(e1, lhs, rhs) && u().is_const_char(lhs, ch) && u().is_const_char(rhs, ch2) && ch != ch2)
else if (m().is_not(e, e1) && m().is_eq(e1, lhs, rhs) && u().is_const_char(lhs, ch) && u().is_const_char(rhs, ch2) && ch != ch2) {
// trivially true
continue; continue;
} else if (u().is_char_le(e, lhs, rhs) && u().is_const_char(lhs, ch) && u().is_const_char(rhs, ch2) && ch <= ch2)
else if (m().is_false(e) || (m().is_not(e, e1) && m().is_eq(e1, lhs, rhs) && lhs == rhs)) { continue;
// trivially false else if (m().is_not(e, e1) && u().is_char_le(e1, lhs, rhs) && u().is_const_char(lhs, ch) && u().is_const_char(rhs, ch2) && ch > ch2)
cond = m().mk_false(); continue;
return; // trivially false conditions
} else if (m().is_false(e) || (m().is_not(e, e1) && m().is_eq(e1, lhs, rhs) && lhs == rhs))
ranges.reset();
else if (u().is_char_le(e, lhs, rhs) && u().is_const_char(lhs, ch) && u().is_const_char(rhs, ch2) && ch > ch2)
ranges.reset();
else if (m().is_not(e, e1) && u().is_char_le(e1, lhs, rhs) && u().is_const_char(lhs, ch) && u().is_const_char(rhs, ch2) && ch <= ch2)
ranges.reset();
else { else {
all_ranges = false; all_ranges = false;
break; break;
@ -5163,6 +5030,8 @@ void seq_rewriter::elim_condition(expr* elem, expr_ref& cond) {
cond = m().mk_true(); cond = m().mk_true();
return; return;
} }
// removes all the trivially true conditions from conds
conds.set(conds_range);
} }
} }

10
src/ast/rewriter/seq_rewriter.h
View file

@ -223,11 +223,6 @@ class seq_rewriter {
expr_ref merge_regex_sets(expr* r1, expr* r2, expr* unit, std::function<bool(expr*, expr*&, expr*&)>& decompose, std::function<expr* (expr*, expr*)>& compose); expr_ref merge_regex_sets(expr* r1, expr* r2, expr* unit, std::function<bool(expr*, expr*&, expr*&)>& decompose, std::function<expr* (expr*, expr*)>& compose);
// Apply simplifications and keep the representation normalized
// Assuming r1 and r2 are normalized
expr_ref mk_regex_union_normalize(expr* r1, expr* r2);
expr_ref mk_regex_inter_normalize(expr* r1, expr* r2);
// elem is (:var 0) and path a condition that may have (:var 0) as a free variable // elem is (:var 0) and path a condition that may have (:var 0) as a free variable
// simplify path, e.g., (:var 0) = 'a' & (:var 0) = 'b' is simplified to false // simplify path, e.g., (:var 0) = 'a' & (:var 0) = 'b' is simplified to false
expr_ref simplify_path(expr* elem, expr* path); expr_ref simplify_path(expr* elem, expr* path);
@ -423,5 +418,10 @@ public:
// heuristic elimination of element from condition that comes form a derivative. // heuristic elimination of element from condition that comes form a derivative.
// special case optimization for conjunctions of equalities, disequalities and ranges. // special case optimization for conjunctions of equalities, disequalities and ranges.
void elim_condition(expr* elem, expr_ref& cond); void elim_condition(expr* elem, expr_ref& cond);
/* Apply simplifications to the union to keep the union normalized (r1 and r2 are not normalized)*/
expr_ref mk_regex_union_normalize(expr* r1, expr* r2);
/* Apply simplifications to the intersection to keep it normalized (r1 and r2 are not normalized)*/
expr_ref mk_regex_inter_normalize(expr* r1, expr* r2);
}; };

50
src/ast/seq_decl_plugin.cpp
View file

@ -831,6 +831,39 @@ app* seq_util::mk_lt(expr* ch1, expr* ch2) const {
return m.mk_not(mk_le(ch2, ch1)); return m.mk_not(mk_le(ch2, ch1));
} }
bool seq_util::is_char_const_range(expr const* x, expr* e, unsigned& l, unsigned& u, bool& negated) const {
expr* a, * b, * e1, * e2, * lb, * ub;
e1 = e;
negated = (m.is_not(e, e1)) ? true : false;
if (m.is_eq(e1, a, b) && (a == x && is_const_char(b, l))) {
u = l;
return true;
}
if (is_char_le(e1, a, b) && a == x && is_const_char(b, u)) {
// (x <= u)
l = 0;
return true;
}
if (is_char_le(e1, a, b) && b == x && is_const_char(a, l)) {
// (l <= x)
u = max_char();
return true;
}
if (m.is_and(e1, e1, e2) && is_char_le(e1, lb, a) && a == x && is_const_char(lb, l) &&
is_char_le(e2, b, ub) && b == x && is_const_char(ub, u))
// (l <= x) & (x <= u)
return true;
if (m.is_eq(e1, a, b) && b == x && is_const_char(a, l)) {
u = l;
return true;
}
if (m.is_and(e1, e2, e1) && is_char_le(e1, lb, a) && a == x && is_const_char(lb, l) &&
is_char_le(e2, b, ub) && b == x && is_const_char(ub, u))
// (x <= u) & (l <= x)
return true;
return false;
}
bool seq_util::str::is_string(func_decl const* f, zstring& s) const { bool seq_util::str::is_string(func_decl const* f, zstring& s) const {
if (is_string(f)) { if (is_string(f)) {
s = f->get_parameter(0).get_zstring(); s = f->get_parameter(0).get_zstring();
@ -1030,6 +1063,23 @@ app* seq_util::rex::mk_loop(expr* r, unsigned lo, unsigned hi) {
return m.mk_app(m_fid, OP_RE_LOOP, 2, params, 1, &r); return m.mk_app(m_fid, OP_RE_LOOP, 2, params, 1, &r);
} }
expr* seq_util::rex::mk_loop_proper(expr* r, unsigned lo, unsigned hi)
{
if (lo == 0 && hi == 0) {
sort* seq_sort = nullptr;
VERIFY(u.is_re(r, seq_sort));
// avoid creating a loop with both bounds 0
// such an expression is invalid as a loop
// it is BY DEFINITION = epsilon
return mk_epsilon(seq_sort);
}
if (lo == 1 && hi == 1)
// do not create a loop unless it actually is a loop
return r;
parameter params[2] = { parameter(lo), parameter(hi) };
return m.mk_app(m_fid, OP_RE_LOOP, 2, params, 1, &r);
}
app* seq_util::rex::mk_loop(expr* r, expr* lo) { app* seq_util::rex::mk_loop(expr* r, expr* lo) {
expr* rs[2] = { r, lo }; expr* rs[2] = { r, lo };
return m.mk_app(m_fid, OP_RE_LOOP, 0, nullptr, 2, rs); return m.mk_app(m_fid, OP_RE_LOOP, 0, nullptr, 2, rs);

7
src/ast/seq_decl_plugin.h
View file

@ -252,6 +252,12 @@ public:
unsigned max_char() const { return seq.max_char(); } unsigned max_char() const { return seq.max_char(); }
unsigned num_bits() const { return seq.num_bits(); } unsigned num_bits() const { return seq.num_bits(); }
/*
e has a form that is equivalent to l <= x <= u (then negated = false)
or e is equivalent to !(l <= x <= u) (then negated = true)
*/
bool is_char_const_range(expr const* x, expr * e, unsigned& l, unsigned& u, bool& negated) const;
app* mk_skolem(symbol const& name, unsigned n, expr* const* args, sort* range); app* mk_skolem(symbol const& name, unsigned n, expr* const* args, sort* range);
bool is_skolem(expr const* e) const { return is_app_of(e, m_fid, _OP_SEQ_SKOLEM); } bool is_skolem(expr const* e) const { return is_app_of(e, m_fid, _OP_SEQ_SKOLEM); }
@ -498,6 +504,7 @@ public:
app* mk_opt(expr* r) { return m.mk_app(m_fid, OP_RE_OPTION, r); } app* mk_opt(expr* r) { return m.mk_app(m_fid, OP_RE_OPTION, r); }
app* mk_loop(expr* r, unsigned lo); app* mk_loop(expr* r, unsigned lo);
app* mk_loop(expr* r, unsigned lo, unsigned hi); app* mk_loop(expr* r, unsigned lo, unsigned hi);
expr* mk_loop_proper(expr* r, unsigned lo, unsigned hi);
app* mk_loop(expr* r, expr* lo); app* mk_loop(expr* r, expr* lo);
app* mk_loop(expr* r, expr* lo, expr* hi); app* mk_loop(expr* r, expr* lo, expr* hi);
app* mk_full_char(sort* s); app* mk_full_char(sort* s);

26
src/util/state_graph.cpp
View file

@ -445,7 +445,7 @@ bool state_graph::write_dgml() {
} }
r = m_state_ufind.next(r); r = m_state_ufind.next(r);
} while (r != s); } while (r != s);
dgml << " Category=\"State\">" << std::endl; dgml << " Category=\"State\" Group=\"Collapsed\">" << std::endl;
if (m_dead.contains(s)) if (m_dead.contains(s))
dgml << "<Category Ref=\"Dead\"/>" << std::endl; dgml << "<Category Ref=\"Dead\"/>" << std::endl;
if (m_live.contains(s)) if (m_live.contains(s))
@ -453,18 +453,35 @@ bool state_graph::write_dgml() {
if (m_unexplored.contains(s)) if (m_unexplored.contains(s))
dgml << "<Category Ref=\"Unexplored\"/>" << std::endl; dgml << "<Category Ref=\"Unexplored\"/>" << std::endl;
dgml << "</Node>" << std::endl; dgml << "</Node>" << std::endl;
dgml << "<Node Id=\"" << s << "info\" Label=\"";
r = s;
dgml << s << "=";
m_state_pp.pp_state_label(dgml, r);
do {
if (r != s) {
dgml << "&#13;" << r << "=";
m_state_pp.pp_state_label(dgml, r);
}
r = m_state_ufind.next(r);
} while (r != s);
dgml << "\"" << std::endl;
dgml << " Category=\"StateInfo\">" << std::endl;
dgml << "</Node>" << std::endl;
} }
} }
dgml << "</Nodes>" << std::endl; dgml << "</Nodes>" << std::endl;
dgml << "<Links>" << std::endl; dgml << "<Links>" << std::endl;
for (auto s : m_seen) { for (auto s : m_seen) {
if (m_state_ufind.is_root(s)) if (m_state_ufind.is_root(s)) {
for (auto t : m_targets[s]) { for (auto t : m_targets[s]) {
dgml << "<Link Source=\"" << s << "\" Target=\"" << t << "\" Category=\"Transition\">" << std::endl; dgml << "<Link Source=\"" << s << "\" Target=\"" << t << "\" Category=\"Transition\">" << std::endl;
if (!m_sources_maybecycle[t].contains(s)) if (!m_sources_maybecycle[t].contains(s))
dgml << "<Category Ref=\"Noncycle\"/>" << std::endl; dgml << "<Category Ref=\"Noncycle\"/>" << std::endl;
dgml << "</Link>" << std::endl; dgml << "</Link>" << std::endl;
} }
dgml << "<Link Source=\"" << s << "\" Target=\"" << s << "info\" Category=\"Contains\">" << std::endl;
dgml << "</Link>" << std::endl;
}
} }
dgml << "</Links>" << std::endl; dgml << "</Links>" << std::endl;
dgml << "<Categories>" << std::endl dgml << "<Categories>" << std::endl
@ -494,6 +511,11 @@ bool state_graph::write_dgml() {
<< "<Setter Property=\"Stroke\" Value=\"black\"/>" << std::endl << "<Setter Property=\"Stroke\" Value=\"black\"/>" << std::endl
<< "<Setter Property=\"Background\" Value=\"white\"/>" << std::endl << "<Setter Property=\"Background\" Value=\"white\"/>" << std::endl
<< "<Setter Property=\"MinWidth\" Value=\"0\"/>" << std::endl << "<Setter Property=\"MinWidth\" Value=\"0\"/>" << std::endl
<< "<Setter Property=\"FontSize\" Value=\"12\"/>" << std::endl
<< "</Style>" << std::endl
<< "<Style TargetType=\"Node\" GroupLabel=\"StateInfo\" ValueLabel=\"True\">" << std::endl
<< "<Setter Property=\"Stroke\" Value=\"white\"/>" << std::endl
<< "<Setter Property=\"FontSize\" Value=\"24\"/>" << std::endl
<< "</Style>" << std::endl << "</Style>" << std::endl
<< "<Style TargetType=\"Link\" GroupLabel=\"Transition\" ValueLabel=\"True\">" << std::endl << "<Style TargetType=\"Link\" GroupLabel=\"Transition\" ValueLabel=\"True\">" << std::endl
<< "<Condition Expression=\"HasCategory('Transition')\"/>" << std::endl << "<Condition Expression=\"HasCategory('Transition')\"/>" << std::endl