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/* See LICENSE file for copyright and license details. */
#include "internals.h"
static inline void
zxor_impl(zahl_char_t *restrict a, const zahl_char_t *restrict b, size_t n)
{
size_t i;
for (i = 0; i < n; i++)
a[i] ^= b[i];
}
void
zxor(z_t a, z_t b, z_t c)
{
size_t n, m;
if (unlikely(zzero(b))) {
SET(a, c);
return;
} else if (unlikely(zzero(c))) {
SET(a, b);
return;
}
m = MAX(b->used, c->used);
n = b->used + c->used - m;
ENSURE_SIZE(a, m);
if (a == b) {
if (a->used < c->used)
zmemcpy(a->chars + n, c->chars + n, m - n);
zxor_impl(a->chars, c->chars, n);
} else if (unlikely(a == c)) {
if (a->used < b->used)
zmemcpy(a->chars + n, b->chars + n, m - n);
zxor_impl(a->chars, b->chars, n);
} else if (m == b->used) {
zmemcpy(a->chars, b->chars, m);
zxor_impl(a->chars, c->chars, n);
} else {
zmemcpy(a->chars, c->chars, m);
zxor_impl(a->chars, b->chars, n);
}
a->used = m;
TRIM_AND_SIGN(a, 1 - 2 * ((zsignum(b) ^ zsignum(c)) < 0));
}
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