[ was: Re: [PATCH] Check TYPE_OVERFLOW_WRAPS for parloops reductions ]

On 22/07/15 18:13, Tom de Vries wrote:
> 0003-Check-TYPE_OVERFLOW_WRAPS-for-parloops-reductions.patch
>
>
> Check TYPE_OVERFLOW_WRAPS for parloops reductions
>
> 2015-07-21  Tom de Vries<tom@codesourcery.com>
>
> 	* tree-parloops.c (gather_scalar_reductions): Add arg to call to
> 	vect_force_simple_reduction.
> 	* tree-vect-loop.c (vect_analyze_scalar_cycles_1): Same.
> 	(vect_is_simple_reduction_1): Add and handle
> 	need_wrapping_integral_overflow parameter.
> 	(vect_is_simple_reduction, vect_force_simple_reduction): Add and pass
> 	need_wrapping_integral_overflow parameter.
> 	(vectorizable_reduction): Add arg to call to vect_is_simple_reduction.
> 	* tree-vectorizer.h (vect_force_simple_reduction): Add parameter to decl.
>
> 	* gcc.dg/autopar/outer-4.c: Add xfail.
> 	* gcc.dg/autopar/outer-5.c: Same.
> 	* gcc.dg/autopar/outer-6.c: Same.
> 	* gcc.dg/autopar/reduc-2.c: Same.
> 	* gcc.dg/autopar/reduc-2char.c: Same.
> 	* gcc.dg/autopar/reduc-2short.c: Same.
> 	* gcc.dg/autopar/reduc-8.c: Same.
> 	* gcc.dg/autopar/uns-outer-4.c: New test.
> 	* gcc.dg/autopar/uns-outer-5.c: New test.
> 	* gcc.dg/autopar/uns-outer-6.c: New test.

> diff --git a/gcc/testsuite/gcc.dg/autopar/uns-outer-4.c b/gcc/testsuite/gcc.dg/autopar/uns-outer-4.c
> new file mode 100644
> index 0000000..ef9fc2a
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/autopar/uns-outer-4.c
> @@ -0,0 +1,36 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -ftree-parallelize-loops=4 -fdump-tree-parloops-details -fdump-tree-optimized" } */
> +
> +void abort (void);
> +
> +unsigned int g_sum=0;
> +unsigned int x[500][500];
> +
> +void __attribute__((noinline))
> +parloop (int N)
> +{
> +  int i, j;
> +  unsigned int sum;
> +
> +  /* Double reduction is currently not supported, outer loop is not
> +     parallelized.  Inner reduction is detected, inner loop is
> +     parallelized.  */
> +  sum = 0;
> +  for (i = 0; i < N; i++)
> +    for (j = 0; j < N; j++)
> +      sum += x[i][j];
> +
> +  g_sum = sum;
> +}
> +
> +int
> +main (void)
> +{
> +  parloop (500);
> +
> +  return 0;
> +}
> +
> +
> +/* { dg-final { scan-tree-dump-times "parallelizing outer loop" 1 "parloops" { xfail *-*-* } } } */
> +/* { dg-final { scan-tree-dump-times "loopfn" 4 "optimized" { xfail *-*-* } } } */

We currently get an XPASS for the last xfail.

The inner loop is paralllelized, so the split-off function loopfn exists.

Committed this follow-up patch to trunk, to remove the incorrect xfail.

Thanks,
- Tom