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/* { dg-do run } */
/* { dg-options "-fdump-tree-crc-details" } */
/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Os" "-O3" "-flto"} } */
#include <stdlib.h>
typedef unsigned char uint8_t;
__attribute__ ((noinline,optimize(0)))
uint8_t gencrc_O0 (uint8_t *data, size_t len) {
uint8_t crc = 0xff;
size_t i, j;
for (i = 0; i < len; i++) {
crc ^= data[i];
for (j = 0; j < 8; j++) {
if ((crc & 0x80) != 0)
crc = (uint8_t) ((crc << 1) ^ 0x31);
else
crc <<= 1;
}
}
return crc;
}
uint8_t gencrc (uint8_t *data, size_t len) {
uint8_t crc = 0xff;
size_t i, j;
for (i = 0; i < len; i++) {
crc ^= data[i];
for (j = 0; j < 8; j++) {
if ((crc & 0x80) != 0)
crc = (uint8_t) ((crc << 1) ^ 0x31);
else
crc <<= 1;
}
}
return crc;
}
int main ()
{
for (uint8_t i = 0; i < 255; i++)
{
uint8_t res1 = gencrc_O0 (&i, 1);
uint8_t res2 = gencrc (&i, 1);
if (res1 != res2)
__builtin_abort ();
}
__builtin_exit (0);
}
/* { dg-final { scan-tree-dump "gencrc 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 "Polynomial's value is \\\{\[0, \]*0, 0, 1, 1, 0, 0, 0, 1\\\}" "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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