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/* { dg-do run } */
/* { dg-options "-fdump-tree-crc-details" } */
/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Os" "-flto" } } */
#include <stdlib.h>
__attribute__ ((noinline,optimize(0)))
unsigned short calc_crc_O0 (unsigned short crc, unsigned char data)
{
unsigned int i, j, org, dst;
org = data;
dst = 0;
for (i = 0; i < 8; i++) {
org <<= 1;
dst >>= 1;
if (org & 0x100)
dst |= 0x80;
}
data = (unsigned char) dst;
crc ^= (unsigned int) data << (16 - 8);
for (j = 0; j < 8; j++) {
if (crc & 0x8000U)
crc = (crc << 1) ^ 0x1021U ;
else
crc <<= 1 ;
}
return crc;
}
unsigned short calc_crc (unsigned short crc, unsigned char data)
{
unsigned int i, j, org, dst;
org = data;
dst = 0;
for (i = 0; i < 8; i++) {
org <<= 1;
dst >>= 1;
if (org & 0x100)
dst |= 0x80;
}
data = (unsigned char) dst;
crc ^= (unsigned int) data << (16 - 8);
for (j = 0; j < 8; j++) {
if (crc & 0x8000U)
crc = (crc << 1) ^ 0x1021U ;
else
crc <<= 1 ;
}
return crc;
}
int main ()
{
unsigned short crc = 0x0D80;
for (unsigned char i = 0; i < 255; i++)
{
unsigned short res1 = calc_crc_O0 (crc, i);
unsigned short res2 = calc_crc (crc, i);
if (res1 != res2)
__builtin_abort ();
crc = res1;
}
__builtin_exit (0);
}
/* { dg-final { scan-tree-dump "calc_crc 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-times "Polynomial's value is \\\{\[0, \]*1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1\\\}" 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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