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/* { dg-do compile } */
/* { dg-options "-fdump-tree-crc-details" } */
/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Os" "-flto" } } */
#include <stdint.h>
#include <stdio.h>
typedef unsigned short ee_u16;
typedef unsigned char ee_u8;
int a;
ee_u16 crcu8 (ee_u8 data, ee_u16 crc) {
ee_u8 i = 0, x16 = 0, carry = 0;
for (i = 0; i < 8; i++) {
a++; // this is moved outside of the loop
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()
{
printf ("%04X\n", crcu8 (0, 0xaa));
printf ("%d", a);
}
/* { dg-final { scan-tree-dump "crcu8 function maybe contains CRC calculation." "crc" } } */
/* { dg-final { scan-tree-dump "Loop iteration number is 7" "crc" } } */
/* { dg-final { scan-tree-dump "Bit reversed" "crc" } } */
/* { dg-final { scan-tree-dump "calculates CRC!" "crc" } } */
/* { dg-final { scan-tree-dump "Polynomial's value is \\\{\[0, \]*1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1\\\}" "crc" } } */
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