On Wed, Jun 22, 2011 at 7:02 PM, Jakub Jelinek <ja...@redhat.com> wrote:
> Hi!
>
> This bug has been introduced recently, we shouldn't take debug uses into
> account when deciding whether to optimize.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
Ok.
Thanks,
Richard.
> 2011-06-22 Jakub Jelinek <ja...@redhat.com>
>
> PR debug/49496
> * tree-vect-patterns.c (vect_recog_widen_mult_pattern): Ignore debug
> uses.
>
> * gcc.dg/pr49496.c: New test.
>
> --- gcc/tree-vect-patterns.c.jj 2011-06-17 11:02:19.000000000 +0200
> +++ gcc/tree-vect-patterns.c 2011-06-22 11:23:08.000000000 +0200
> @@ -557,6 +557,8 @@ vect_recog_widen_mult_pattern (VEC (gimp
>
> FOR_EACH_IMM_USE_FAST (use_p, imm_iter, lhs)
> {
> + if (is_gimple_debug (USE_STMT (use_p)))
> + continue;
> use_stmt = USE_STMT (use_p);
> nuses++;
> }
> --- gcc/testsuite/gcc.dg/pr49496.c.jj 2011-06-22 11:24:30.000000000 +0200
> +++ gcc/testsuite/gcc.dg/pr49496.c 2011-06-22 11:28:33.000000000 +0200
> @@ -0,0 +1,20 @@
> +/* PR debug/49496 */
> +/* { dg-do compile } */
> +/* { dg-options "-O3 -fcompare-debug" } */
> +
> +unsigned short u[8], s1[8], s2[8];
> +
> +void bar (unsigned short *);
> +
> +void
> +foo (void)
> +{
> + unsigned short e[8];
> + int i;
> + for (i = 0; i < 8; i++)
> + {
> + int tmp = s1[i] * s2[i];
> + e[i] = (tmp & 0xffff0000) >> 16;
> + }
> + bar (e);
> +}
>
> Jakub
>
