/*
* Collect all terms that satisfy predicate f
* - add them to vector v
* - if f(aux, t) returns true, add t to vector v
* - if all is false, only the terms in model->map are considered
* - if all is true, the terms in model->map and model->alias are considered
* - f must not have side effects
*
* - v is not reset. All terms collected are added to v
*/
void model_collect_terms(model_t *model, bool all, void *aux, model_filter_t f, ivector_t *v) {
int_hmap_t *hmap;
int_hmap_pair_t *r;
hmap = &model->map;
r = int_hmap_first_record(hmap);
while (r != NULL) {
if (f(aux, r->key)) {
ivector_push(v, r->key);
}
r = int_hmap_next_record(hmap, r);
}
hmap = model->alias_map;
if (all && hmap != NULL) {
r = int_hmap_first_record(hmap);
while (r != NULL) {
if (f(aux, r->key)) {
ivector_push(v, r->key);
}
r = int_hmap_next_record(hmap, r);
}
}
}
clause_ref_t clause_db_new_clause(clause_db_t* db, const mcsat_literal_t* literals, uint32_t size, mcsat_clause_tag_t tag) {
mcsat_tagged_clause_t* clause_memory;
uint32_t clause_size;
clause_ref_t clause_ref;
assert(tag.type == CLAUSE_LEMMA || tag.var != variable_null);
// Allocate the clause (size + 1) for null-termination
clause_size = clause_size_in_bytes(size);
clause_memory = allocate(&clause_size, &db->memory, &db->size, &db->capacity);
// Construct the clause and tag it
clause_construct(&clause_memory->clause, literals, size);
clause_memory->tag = tag;
// Compute the clause reference
clause_ref = clause_get_ref(db, clause_memory);
// Remember the clause
assert(clause_db_is_clause(db, clause_ref, true));
ivector_push(&db->clauses, clause_ref);
// Return the reference
return clause_ref;
}
/*
* Undo assert_var/keep record poly
* - stop on the top-most 'INCREASE_DLEVEL'
*/
static void op_stack_backtrack(test_bench_t *bench) {
op_stack_t *stack;
ivector_t saved_polys;
uint32_t i;
int32_t id;
stack = &bench->stack;
init_ivector(&saved_polys, 10);
i = stack->top;
for (;;) {
assert(i > 0);
i --;
switch (stack->data[i].tag) {
case RECORD_POLY:
id = stack->data[i].arg.rec_id;
ivector_push(&saved_polys, id);
break;
case ASSERT_EQ: // undo
case PROPAGATE: // undo
break;
case INCREASE_DLEVEL:
goto done;
case PUSH:
default:
assert(false);
break;
}
}
done:
stack->top = i;
if (bench->conflict) {
// check whether the conflict equality has been removed
assert(bench->conflict_eq >= 0);
if (i <= bench->conflict_eq) {
bench->conflict_eq = -1;
bench->conflict = false;
bench->mngr_conflict = false;
printf("---> Conflict resolved\n");
fflush(stdout);
}
}
// redo the record poly operations
i = saved_polys.size;
while (i > 0) {
i --;
id = saved_polys.data[i];
push_record_poly(stack, id);
}
delete_ivector(&saved_polys);
}
/*
* Add all indices in the domain of map to vector v
* - the default index (null_particle) is not added if it's present in map
*/
void collect_map_indices(map_t *map, ivector_t *v) {
uint32_t i, n;
n = map->nelems;
for (i=0; i<n; i++) {
ivector_push(v, map->data[i].index);
}
}
/*
* Add term t to the store:
* - t is added as last element of store->terms[i] where i = index for type of t
*/
static void type_store_add_term(type_store_t *store, term_t t) {
uint32_t i;
type_t tau;
assert(good_term(__yices_globals.terms, t));
tau = term_type(__yices_globals.terms, t);
i = type_store_get_type(store, tau);
ivector_push(store->terms + i, t);
}
/*
* Collect all children of i in vector v
* - i must be the start of a valie expression
* - v must be initialized and empty (if not empty, the children
* are added to v).
*/
void collect_subexpr(etk_queue_t *queue, int32_t i, ivector_t *v) {
int32_t k, n;
assert(start_token(queue, i));
if (queue->tk[i].key == ETK_OPEN) {
n = queue->tk[i].val;
k = i+1;
while (k < n) {
assert(good_token(queue, k));
ivector_push(v, k);
k = token_sibling(queue, k);
}
assert(k == n);
}
}
/*
* Extract the common part of p and q:
* - p and q must both be normalized
* - the set of variables x_1, ..., x_k such that
* x_i occurs with the same coefficient in p and q is added to vector v.
* - these variables are in increasing order
*/
void monarray_pair_common_part(monomial_t *p, monomial_t *q, ivector_t *v) {
int32_t x, y;
x = p->var;
y = q->var;
while (x < max_idx && y < max_idx) {
if (x < y) {
p ++;
x = p->var;
} else if (y < x) {
q ++;
y = q->var;
} else {
if (q_eq(&p->coeff, &q->coeff)) {
ivector_push(v, x);
}
p ++;
x = p->var;
q ++;
y = q->var;
}
}
}
/*
* Flatten all terms in flat->queue to conjuncts
* - all terms in the queue must also be in the cache
* - f_ite: if true, flatten (ite c a b)
* - f_iff: if true, flatten (iff a b)
*/
static void flattener_build_conjuncts(flattener_t *flat, bool f_ite, bool f_iff) {
term_table_t *terms;
int_queue_t *queue;
composite_term_t *d;
term_t t, u, v;
uint32_t i, n;
queue = &flat->queue;
terms = flat->terms;
while (! int_queue_is_empty(queue)) {
t = int_queue_pop(queue);
switch (term_kind(terms, t)) {
case ITE_TERM:
case ITE_SPECIAL:
d = ite_term_desc(terms, t);
assert(d->arity == 3);
if (f_ite && is_boolean_term(terms, d->arg[1])) {
assert(is_boolean_term(terms, d->arg[2]));
/*
* If t is (ite C A B)
* u := (C => A)
* v := (not C => B)
* Otherwise, t is (not (ite C A B))
* u := (C => not A)
* v := (not C => not B)
*/
u = d->arg[1]; // A
v = d->arg[2]; // B
if (is_neg_term(t)) {
u = opposite_term(u);
v = opposite_term(v);
}
u = mk_implies(flat->manager, d->arg[0], u); // (C => u)
v = mk_implies(flat->manager, opposite_term(d->arg[0]), v); // (not C) => v
flattener_push_term(flat, u);
flattener_push_term(flat, v);
continue;
}
break;
case EQ_TERM:
d = eq_term_desc(terms, t);
assert(d->arity == 2);
if (f_iff && is_boolean_term(terms, d->arg[0])) {
assert(is_boolean_term(terms, d->arg[1]));
/*
* t is either (iff A B) or (not (iff A B)):
*/
u = d->arg[0]; // A
v = d->arg[1]; // B
if (is_neg_term(t)) {
u = opposite_term(u);
}
// flatten to (u => v) and (v => u)
t = mk_implies(flat->manager, u, v); // (u => v)
u = mk_implies(flat->manager, v, u); // (v => u);
flattener_push_term(flat, t);
flattener_push_term(flat, u);
continue;
}
break;
case OR_TERM:
if (is_neg_term(t)) {
/*
* t is (not (or a[0] ... a[n-1]))
* it flattens to (and (not a[0]) ... (not a[n-1]))
*/
d = or_term_desc(terms, t);
n = d->arity;
for (i=0; i<n; i++) {
flattener_push_term(flat, opposite_term(d->arg[i]));
}
continue;
}
break;
default:
break;
}
ivector_push(&flat->resu, t);
}
// clean up the cache
assert(int_queue_is_empty(queue));
int_hset_reset(&flat->cache);
}
/*
* Process disjuncts and universal quantifiers
* - input = all terms in the queue
* - f_ite: if true, flatten (ite c a b)
* - f_iff: if true, flatten (iff a b)
*/
static void flattener_forall_disjuncts(flattener_t *flat, bool f_ite, bool f_iff) {
term_table_t *terms;
int_queue_t *queue;
composite_term_t *d;
term_t t, u, v;
uint32_t i, n;
queue = &flat->queue;
terms = flat->terms;
while (! int_queue_is_empty(queue)) {
t = int_queue_pop(queue);
switch (term_kind(terms, t)) {
case ITE_TERM:
case ITE_SPECIAL:
d = ite_term_desc(terms, t);
assert(d->arity == 3);
if (f_ite && is_boolean_term(terms, d->arg[1])) {
assert(is_boolean_term(terms, d->arg[2]));
/*
* If t is (ite C A B)
* u := (C AND A)
* v := (not C AND B)
* Otherwise, t is (not (ite C A B))
* u := (C AND not A)
* v := (not C AND not B)
*/
u = d->arg[1]; // A
v = d->arg[2]; // B
if (is_neg_term(t)) {
u = opposite_term(u); // NOT A
v = opposite_term(v); // NOT B
}
u = mk_binary_and(flat->manager, d->arg[0], u); // (C AND u)
v = mk_binary_and(flat->manager, opposite_term(d->arg[0]), v); // (not C) AND v
flattener_push_term(flat, u);
flattener_push_term(flat, v);
continue;
}
break;
case EQ_TERM:
d = eq_term_desc(terms, t);
assert(d->arity == 2);
if (f_iff && is_boolean_term(terms, d->arg[0])) {
assert(is_boolean_term(terms, d->arg[1]));
/*
* t is either (iff A B) or (not (iff A B)):
*/
u = d->arg[0]; // A
v = d->arg[1]; // B
if (is_neg_term(t)) {
u = opposite_term(u);
}
// flatten to (u AND v) or ((not u) AND (not v))
t = mk_binary_and(flat->manager, u, v); // (u AND v)
u = mk_binary_and(flat->manager, opposite_term(u), opposite_term(v)); // (not u AND not v);
flattener_push_term(flat, t);
flattener_push_term(flat, u);
continue;
}
break;
case OR_TERM:
if (is_pos_term(t)) {
/*
* t is (or a[0] ... a[n-1])
*/
d = or_term_desc(terms, t);
n = d->arity;
for (i=0; i<n; i++) {
flattener_push_term(flat, d->arg[i]);
}
continue;
}
break;
case FORALL_TERM:
if (is_pos_term(t)) {
d = forall_term_desc(terms, t);
n = d->arity;
assert(n >= 2);
/*
* t is (FORALL x_0 ... x_k : body)
* body is the last argument in the term descriptor
*/
flattener_push_term(flat, d->arg[n-1]);
continue;
}
break;
default:
break;
}
ivector_push(&flat->resu, t);
}
// clean up the cache
assert(int_queue_is_empty(queue));
int_hset_reset(&flat->cache);
}
static int build_instance(char *filename, smt_core_t *core) {
int l, n, c_idx, literal, nvars, nclauses;
char *s;
FILE *f;
ivector_t buffer;
f = fopen(filename, "r");
if (f == NULL) {
perror(filename);
return OPEN_ERROR;
}
s = fgets(line, MAX_LINE, f);
l = 1; /* line number */
if (s == NULL) {
fprintf(stderr, "%s: empty file\n", filename);
fclose(f);
return FORMAT_ERROR;
}
/* skip empty and comment lines */
while (*s == 'c' || *s == '\n') {
s = fgets(line, MAX_LINE, f);
l ++;
if (s == NULL) {
fprintf(stderr, "Format error: file %s, line %d\n", filename, l);
fclose(f);
return FORMAT_ERROR;
}
}
/* read problem size */
n = sscanf(s, "p cnf %d %d", &nvars, &nclauses);
if (n != 2 || nvars < 0 || nclauses < 0) {
fprintf(stderr, "Format error: file %s, line %d\n", filename, l);
fclose(f);
return FORMAT_ERROR;
}
/* initialize core for nvars */
init_sat_solver(core, nvars);
/* initialize the clause buffer */
init_ivector(&buffer, 10);
/* now read the clauses and translate them */
c_idx = 0;
while (c_idx < nclauses) {
for (;;) {
literal = read_literal(f, nvars);
if (literal < 0) break;
ivector_push(&buffer, literal);
}
if (literal != END_OF_CLAUSE) {
fprintf(stderr, "Format error: file %s\n", filename);
fclose(f);
return FORMAT_ERROR;
}
add_clause(core, buffer.size, buffer.data);
c_idx ++;
ivector_reset(&buffer);
}
delete_ivector(&buffer);
fclose(f);
return 0;
}
/*
* Check whether f is a range constraint
* - if so return a term t and fill in vector v with the formula's constants
* - otherwise, return NULL_TERM
*
* Side effect: use queue and cache.
* v may be modified even if the function returns NULL_TERM.
*/
static term_t formula_is_range_constraint(sym_breaker_t *breaker, term_t f, ivector_t *v) {
int_queue_t *queue;
int_hset_t *cache;
term_table_t *terms;
intern_tbl_t *intern;
term_t r, t;
term_t x, a, y, b;
uint32_t neqs;
queue = &breaker->queue;
cache = &breaker->cache;
terms = breaker->terms;
intern = &breaker->ctx->intern;
assert(int_queue_is_empty(queue) && int_hset_is_empty(cache));
push_term(queue, cache, f);
neqs = 0;
t = NULL_TERM;
y = NULL_TERM; // prevent GCC warning
b = NULL_TERM; // prevent GCC warning
/*
* Invariants:
* - neqs = number of equality atoms seen so far
* - if neq == 1, then the first equality is stored as (y == b) where b is a constant
* - if neq >= 2, then all equalities seen so far were of the form (x == constant)
*/
do {
// r := root of the first term in the queue
r = intern_tbl_get_root(intern, int_queue_pop(queue));
switch (match_term(breaker->ctx, r, &a, &x)) {
case MATCH_FALSE: // skip false terms
break;
case MATCH_OR:
push_children(queue, cache, or_term_desc(terms, r));
break;
case MATCH_EQ:
assert(term_is_constant(terms, a));
if (neqs == 0) {
y = x; b = a;
} else if (neqs == 1) {
/*
* First equality: (y == b). Second equality: (x == a)
*/
if (y == x) {
// y is the common term, a and b are constant
ivector_push(v, b);
ivector_push(v, a);
} else if (y == a && term_is_uconst(terms, x)) {
// y is the common term, b and x are constant
ivector_push(v, b);
ivector_push(v, a);
} else if (x == b && term_is_uconst(terms, y)) {
// b is the common term, y and a are constant
ivector_push(v, y);
ivector_push(v, a);
y = b;
} else if (a == b && term_is_uconst(terms, y) && term_is_uconst(terms, x)) {
// b is the common term, y and x are constant
ivector_push(v, y);
ivector_push(v, x);
y = b;
} else {
// abort
goto done;
}
} else {
/*
* All equalities so far have the form (y == constant)
* - the current equality is (x == a)
*/
if (y == x) {
ivector_push(v, a); // match
} else if (y == a && term_is_constant(terms, x)) {
ivector_push(v, x); // swap a and x
} else {
// no match
goto done;
}
}
neqs ++;
break;
case MATCH_IFF:
/*
* the returned term x is equivalent to t
*/
push_term(queue, cache, x);
break;
default:
// abort
goto done;
}
} while (! int_queue_is_empty(queue));
assert(y != NULL_TERM && t == NULL_TERM);
if (neqs >= 2) {
assert(v->size == neqs);
t = y;
}
done:
int_queue_reset(queue);
int_hset_reset(cache);
return t;
}