aboutsummaryrefslogtreecommitdiff
path: root/gcc/testsuite/gcc.dg/torture/crc-side-instr-7.c
blob: ce8f8a86fc219544c3b5b61df579603efbff6359 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
/* { dg-do compile } */
/* { dg-options "-fdump-tree-crc-details" } */
/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Os" "-flto" } } */

#include <stdio.h>
typedef unsigned short ee_u16;
typedef unsigned char ee_u8;

int a[10] = {};
ee_u16 crcu8 (ee_u8 data, ee_u16 crc) {
  ee_u8 i = 0, x16 = 0, carry = 0;
  for (i = 0; i < 8; i++) {
      a[i] = crc;
      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[0]);
}


/* { 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-times "calculates CRC!" 0 "crc" } } */