gcc/testsuite/gcc.dg/vect/vect-reduc-sad.c

   1 /* Disabling epilogues until we find a better way to deal with scans.  */
   2 /* { dg-additional-options "--param vect-epilogues-nomask=0" } */
   3 /* { dg-require-effective-target vect_usad_char } */
   4
   5 #include <stdarg.h>
   6 #include "tree-vect.h"
   7
   8 #define N 64
   9 #define SAD N*N/2
  10
  11 unsigned char X[N] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
  12 unsigned char Y[N] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
  13 int abs (int);
  14
  15 /* Sum of absolute differences between arrays of unsigned char types.
  16    Detected as a sad pattern.
  17    Vectorized on targets that support sad for unsigned chars.  */
  18
  19 __attribute__ ((noinline)) int
  20 foo (int len)
  21 {
  22   int i;
  23   int result = 0;
  24
  25   for (i = 0; i < len; i++)
  26     result += abs (X[i] - Y[i]);
  27
  28   return result;
  29 }
  30
  31
  32 int
  33 main (void)
  34 {
  35   int i;
  36   int sad;
  37
  38   check_vect ();
  39
  40   for (i = 0; i < N; i++)
  41     {
  42       X[i] = i;
  43       Y[i] = N - i;
  44       __asm__ volatile ("");
  45     }
  46
  47   sad = foo (N);
  48   if (sad != SAD)
  49     abort ();
  50
  51   return 0;
  52 }
  53
  54 /* { dg-final { scan-tree-dump "vect_recog_sad_pattern: detected" "vect" } } */
  55 /* { dg-final { scan-tree-dump-times "vectorized 1 loops" 1 "vect" } } */
  56