+cc jakub
On Tue, Feb 4, 2014 at 4:59 PM, Paul Pluzhnikov <ppluzhni...@google.com> wrote:
> Greetings,
>
> The gcc.dg/vect/no-vfa-vect-depend-2.c failed for us, when linked with
> gold, but not when linked with BFD ld.
>
> The problem appears to be off-by-one error causing array out of bounds
> access, fixed by attached patch.
Alternate fix (used in no-vfa-vect-depend-3.c):
--- gcc/testsuite/gcc.dg/vect/no-vfa-vect-depend-2.c (revision 207487)
+++ gcc/testsuite/gcc.dg/vect/no-vfa-vect-depend-2.c (working copy)
@@ -5,8 +5,8 @@
#define N 17
-int ia[N] = {48,45,42,39,36,33,30,27,24,21,18,15,12,9,6,3,0};
-int ib[N] = {48,45,42,39,36,33,30,27,24,21,18,15,12,9,6,3,0};
+int ia[N + 1] = {48,45,42,39,36,33,30,27,24,21,18,15,12,9,6,3,0};
+int ib[N + 1] = {48,45,42,39,36,33,30,27,24,21,18,15,12,9,6,3,0};
int res[N] = {48,192,180,168,156,144,132,120,108,96,84,72,60,48,36,24,12};
__attribute__ ((noinline))
>
> OK for trunk?
>
> Thanks,
>
>
> gcc/testsuite/ChangeLog:
>
> 2014-02-04 Paul Pluzhnikov <ppluzhni...@google.com>
>
> * gcc.dg/vect/no-vfa-vect-depend-2.c (main1): Fix buffer
> overflow.
>
>
> Index: gcc/testsuite/gcc.dg/vect/no-vfa-vect-depend-2.c
> ===================================================================
> --- gcc/testsuite/gcc.dg/vect/no-vfa-vect-depend-2.c (revision 207487)
> +++ gcc/testsuite/gcc.dg/vect/no-vfa-vect-depend-2.c (working copy)
> @@ -15,7 +15,7 @@
> int i;
>
> /* Not vectorizable due to data dependence: dependence distance 1. */
> - for (i = N - 1; i >= 0; i--)
> + for (i = N - 2; i >= 0; i--)
> {
> ia[i] = ia[i+1] * 4;
> }
> @@ -28,7 +28,7 @@
> }
>
> /* Vectorizable. Dependence distance -1. */
> - for (i = N - 1; i >= 0; i--)
> + for (i = N - 2; i >= 0; i--)
> {
> ib[i+1] = ib[i] * 4;
> }
--
Paul Pluzhnikov
