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ct/cmp: save the final shift by switching the direction of shifts

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Lucas Gabriel Vuotto 2024-06-11 02:29:00 +00:00
parent d90236bfb9
commit fb2139eeee
1 changed files with 5 additions and 5 deletions
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10
ct.c
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@ -25,10 +25,10 @@ lc_ct_cmp(const uint8_t *x, const uint8_t *y, size_t l)
for (; l > 0; l--)
r |= *x++ ^ *y++;
/* Ensures that if any bit is set, then bit 7 is set. */
r |= r << 4;
r |= r << 2;
r |= r << 1;
/* Ensures that if any bit is set, then LSB is set. */
r |= r >> 4;
r |= r >> 2;
r |= r >> 1;
return 0xffffffff + ((r & 0x80) >> 7);
return 0xffffffff + (r & 1);
}