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/* See LICENSE file for copyright and license details. */
#ifndef TEST
#include "common.h"
LIBNORMALFORM_SENTENCE *
(libnormalform_xor2)(LIBNORMALFORM_SENTENCE *l, LIBNORMALFORM_SENTENCE *r)
{
int inv;
if (!l || !r) {
libnormalform_free(l);
libnormalform_free(r);
return NULL;
}
if (l->equals(l, r, &inv)) {
libnormalform_free(l);
libnormalform_free(r);
if (!inv) {
/* x ⊕ x = 0 */
return libnormalform_false();
} else {
/* x ⊕ ¬x = 1 */
return libnormalform_true();
}
} else if (l->type == TYPE_TRUE) {
/* 1 ⊕ x = (1 ∨ x) ∧ ¬(1 ∧ x) = 1 ∧ ¬x = ¬x */
r = libnormalform_not(r);
return_r:
libnormalform_free(l);
return r;
} else if (l->type == TYPE_FALSE) {
/* 0 ⊕ x = (0 ∨ x) ∧ ¬(0 ∧ x) = x ∧ ¬0 = x ∧ 1 = x */
goto return_r;
} else if (r->type == TYPE_TRUE) {
/* x ⊕ 1 = 1 ⊕ x = ¬x */
l = libnormalform_not(l);
return_l:
libnormalform_free(r);
return l;
} else if (r->type == TYPE_FALSE) {
/* x ⊕ 0 = 0 ⊕ x = x */
goto return_l;
} else {
return libnormalform_xor2__(l, r);
}
}
#else
#define USE_TWO
#include "libnormalform_xor.c"
#endif
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