static void __expr_eliminate_eq(enum expr_type type, struct expr **ep1, struct expr **ep2)
{
if (e1->type == type) {
__expr_eliminate_eq(type, &e1->left.expr, &e2);
__expr_eliminate_eq(type, &e1->right.expr, &e2);
return;
}
if (e2->type == type) {
__expr_eliminate_eq(type, &e1, &e2->left.expr);
__expr_eliminate_eq(type, &e1, &e2->right.expr);
return;
}
if (e1->type == E_SYMBOL && e2->type == E_SYMBOL &&
e1->left.sym == e2->left.sym &&
(e1->left.sym == &symbol_yes || e1->left.sym == &symbol_no))
return;
if (!expr_eq(e1, e2))
return;
trans_count++;
expr_free(e1); expr_free(e2);
switch (type) {
case E_OR:
e1 = expr_alloc_symbol(&symbol_no);
e2 = expr_alloc_symbol(&symbol_no);
break;
case E_AND:
e1 = expr_alloc_symbol(&symbol_yes);
e2 = expr_alloc_symbol(&symbol_yes);
break;
default:
;
}
}
void
expr_eliminate_eq(struct expr **ep1, struct expr **ep2)
{
if (!e1 || !e2 || e1->type != e2->type)
return;
__expr_eliminate_eq(e1->type, ep1, ep2);
e1 = expr_eliminate_yn(e1);
e2 = expr_eliminate_yn(e2);
}
void expr_eliminate_eq(struct expr **ep1, struct expr **ep2)
{
if (!e1 || !e2)
return;
switch (e1->type) {
case E_OR:
case E_AND:
__expr_eliminate_eq(e1->type, ep1, ep2);
default:
;
}
if (e1->type != e2->type) switch (e2->type) {
case E_OR:
case E_AND:
__expr_eliminate_eq(e2->type, ep1, ep2);
default:
;
}
e1 = expr_eliminate_yn(e1);
e2 = expr_eliminate_yn(e2);
}
