gcc/testsuite/gcc.dg/vect/vect-reduc-dot-s8b.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_int } */
   4
   5 #include <stdarg.h>
   6 #include "tree-vect.h"
   7
   8 #define N 64
   9
  10 #define DOT2 -21856
  11
  12 signed char X[N] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
  13 signed char Y[N] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
  14
  15 /* char->short->short dot product.
  16    The dot-product pattern should be detected.
  17
  18    When the dot-product is detected, the loop should be vectorized on vect_sdot_qi
  19    targets (targets that support dot-product of signed char).
  20    This test would currently fail to vectorize on targets that support
  21    dot-product of chars into an int accumulator.
  22    Alternatively, the loop could also be vectorized as widening-mult + summation,
  23    or with type-conversion support.
  24  */
  25 __attribute__ ((noinline)) short
  26 foo2(int len) {
  27   int i;
  28   short result = 0;
  29
  30   for (i=0; i<len; i++) {
  31     result += (X[i] * Y[i]);
  32   }
  33   return result;
  34 }
  35
  36 int main (void)
  37 {
  38   int i;
  39   short dot2;
  40
  41   check_vect ();
  42
  43   for (i=0; i<N; i++) {
  44     X[i] = i;
  45     Y[i] = 64-i;
  46     __asm__ volatile ("");
  47   }
  48
  49   dot2 = foo2 (N);
  50   if (dot2 != DOT2)
  51     abort ();
  52
  53   return 0;
  54 }
  55
  56 /* { dg-final { scan-tree-dump-times "vect_recog_dot_prod_pattern: detected(?:(?!Analysis failed).)*Analysis succeeded" 1 "vect" { xfail *-*-* } } } */
  57 /* { dg-final { scan-tree-dump-times "vect_recog_widen_mult_pattern: detected(?:(?!Analysis failed).)*Analysis succeeded" 1 "vect" { target vect_widen_mult_qi_to_hi } } } */
  58
  59 /* { dg-final { scan-tree-dump-times "vectorized 1 loops" 1 "vect" { target vect_widen_mult_qi_to_hi } } } */
  60