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/* { dg-do run } */
/* { dg-options "-fdump-tree-crc-details" } */
/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-g" "-Os" "-flto" } } */
/* { dg-require-effective-target int32plus } */
#include <stdlib.h>
typedef unsigned short ee_u16;
typedef unsigned char ee_u8;
__attribute__ ((noinline,optimize(0)))
ee_u16 crcu16_O0 (ee_u16 data, ee_u16 crc) {
ee_u8 i = 0, x16 = 0, carry = 0;
for (i = 0; i < 16; i++) {
x16 = (ee_u8) ((data & 1) ^ ((ee_u8) crc & 1));
data >>= 1;
if (x16 == 1) {
crc ^= 0x4002;
carry = 1;
} else
carry = 0;
crc >>= 1;
if (carry)
crc |= 0x8000;
else
crc &= 0x7fff;
}
return crc;
}
ee_u16 crcu16 (ee_u16 data, ee_u16 crc) {
ee_u8 i = 0, x16 = 0, carry = 0;
for (i = 0; i < 16; i++) {
x16 = (ee_u8) ((data & 1) ^ ((ee_u8) crc & 1));
data >>= 1;
if (x16 == 1) {
crc ^= 0x4002;
carry = 1;
} else
carry = 0;
crc >>= 1;
if (carry)
crc |= 0x8000;
else
crc &= 0x7fff;
}
return crc;
}
int main ()
{
ee_u16 crc = 0x0D80;
for (ee_u16 i = 0; i < 255; i++)
{
ee_u16 res1 = crcu16_O0 (i, crc);
ee_u16 res2 = crcu16 (i, crc);
if (res1 != res2)
__builtin_abort ();
crc = res1;
}
__builtin_exit (0);
}
/* { dg-final { scan-tree-dump "function maybe contains CRC calculation." "crc" } } */
/* { dg-final { scan-tree-dump "Loop iteration number is 15" "crc"} } */
/* { dg-final { scan-tree-dump "Bit reversed" "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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