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/* { dg-do compile } */
/* { dg-options "-fdump-tree-crc" } */
/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Os" "-O3" "-flto" } } */
/* With -O3 the cycles is split into 2,
and one of them calculates CRC (when data != 0).
Thus, when compiling with -O3 there is CRC. */
#include <stdint.h>
uint8_t not_crc(uint8_t crc, uint8_t data) {
crc = crc ^ data;
for (uint8_t i = 0, n = 0; i < 8; i++, n++) {
if ((crc & 0x01) && data)
crc = (crc >> 1) ^ 0x8C;
else
crc >>= 1;
}
return crc;
}
/* { dg-final { scan-tree-dump-times "calculates CRC!" 0 "crc" } } */
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