gcc/testsuite/gcc.dg/vect/vect-reduc-dot-u16b.c

/* Disabling epilogues until we find a better way to deal with scans.  */
/* { dg-additional-options "--param vect-epilogues-nomask=0" } */
/* { dg-require-effective-target vect_int } */

#include <stdarg.h>
#include "tree-vect.h"

#define N 64

#define DOT2 43680

unsigned short X[N] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
unsigned short Y[N] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));

/* ushort->int->uint dot product: the multiplication promotes the ushorts
   to int, and then the product is converted to uint for the addition.  */
__attribute__ ((noinline)) unsigned int
foo2(int len) {
  int i;
  unsigned int result = 0;

  for (i=0; i<len; i++) {
    result += (X[i] * Y[i]);
  }
  return result;
}


int main (void)
{
  unsigned int  dot2;
  int i;

  check_vect ();

  for (i=0; i<N; i++) {
    X[i] = i;
    Y[i] = 64-i;
    __asm__ volatile ("");
  }

  dot2 = foo2 (N);
  if (dot2 != DOT2)
    abort ();

  return 0;
}

/* { dg-final { scan-tree-dump-times "vect_recog_dot_prod_pattern: detected" 1 "vect" } } */

/* { dg-final { scan-tree-dump-times "vectorized 1 loops" 1 "vect" { target { vect_pack_trunc || vect_udot_hi } } } } */