gcc/testsuite/gcc.target/powerpc/pr94613.c

/* { dg-do run } */
/* { dg-require-effective-target vmx_hw } */
/* { dg-options "-O2 -maltivec" } */

#include <altivec.h>

/* The initial implementation of vec_sel used an IF_THEN_ELSE rtx.
   This did NOT match what the vsel instruction does.  vsel is a
   bit-wise operation.  Using IF_THEN_ELSE made the + operation to be
   simplified away in combine.  A plus operation affects other bits in
   the same element. Hence per-element simplifications are wrong for
   vsel.  */
vector unsigned char __attribute__((noinline))
foo (vector unsigned char a, vector unsigned char b, vector unsigned char c)
{
  return vec_sel (a + b, c, a);
}

vector unsigned char __attribute__((noinline))
foor (vector unsigned char a, vector unsigned char b, vector unsigned char c)
{
  return vec_sel (c, a + b, ~a);
}

vector unsigned char __attribute__((noinline))
bar (vector unsigned char a, vector unsigned char b, vector unsigned char c)
{
  return vec_sel (a | b, c, a);
}

int
main ()
{
  vector unsigned char v = (vector unsigned char){ 1 };

  if (foo (v, v, v)[0] != 3)
      __builtin_abort ();

  if (bar (v, v, v)[0] != 1)
    __builtin_abort ();

  if (foor (v, v, v)[0] != 3)
    __builtin_abort ();

  return 0;
}