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/* { dg-do run } */
/* { dg-options "-fdump-tree-crc-details -w" } */
/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-g" "-Os" "-flto" } } */
/* { dg-require-effective-target int32plus } */
#include <stdint.h>
#include <stdlib.h>
__attribute__ ((noinline,optimize(0)))
uint32_t _crc32_O0 (uint8_t data, uint32_t crc) {
int i;
for (i = 0; i < 8; i++) {
if ((crc & 0x80000000) >> 24 ^ (data & 0x80))
crc = (crc << 1) ^ 0x04C11DB7;
else
crc = (crc << 1);
data <<= 1;
}
return crc;
}
uint32_t _crc32 (uint8_t data, uint32_t crc) {
int i;
for (i = 0; i < 8; i++) {
if ((crc & 0x80000000) >> 24 ^ (data & 0x80))
crc = (crc << 1) ^ 0x04C11DB7;
else
crc = (crc << 1);
data <<= 1;
}
return crc;
}
int main ()
{
uint32_t crc = 0;
for (uint8_t i = 0; i < 0xff; i++)
{
uint32_t res1 = _crc32_O0 (i, crc);
uint32_t res2 = _crc32 (i, crc);
crc = res2;
if (res1 != res2)
abort ();
}
}
/* { dg-final { scan-tree-dump "function maybe contains CRC calculation." "crc" } } */
/* { dg-final { scan-tree-dump "Loop iteration number is 7" "crc" } } */
/* { dg-final { scan-tree-dump "Bit forward" "crc" } } */
/* { dg-final { scan-tree-dump "calculates CRC." "crc" } } */
/* { dg-final { scan-tree-dump-times "Couldn't generate faster CRC code." 0 "crc" } } */
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