| Message ID | ye6qwqhagysd.fsf@elbrus2.mtv.corp.google.com |
|---|---|
| State | New |
| Headers | show |
On Tue, Feb 04, 2014 at 04:59:14PM -0800, Paul Pluzhnikov wrote: > gcc/testsuite/ChangeLog: > > 2014-02-04 Paul Pluzhnikov <ppluzhnikov@google.com> > > * gcc.dg/vect/no-vfa-vect-depend-2.c (main1): Fix buffer > overflow. Ok, thanks. > --- 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; > } Jakub
Jakub, On Mon, Feb 10, 2014 at 12:09 AM, Jakub Jelinek <jakub@redhat.com> wrote: > On Tue, Feb 04, 2014 at 04:59:14PM -0800, Paul Pluzhnikov wrote: >> gcc/testsuite/ChangeLog: >> >> 2014-02-04 Paul Pluzhnikov <ppluzhnikov@google.com> >> >> * gcc.dg/vect/no-vfa-vect-depend-2.c (main1): Fix buffer >> overflow. > > Ok, thanks. Sorry, did you vouch for this: - for (i = N - 1; i >= 0; i--) + for (i = N - 2; i >= 0; i--) or that: -int ia[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}; Thanks,
On Tue, Feb 18, 2014 at 06:24:17PM -0800, Paul Pluzhnikov wrote: > Jakub, > > On Mon, Feb 10, 2014 at 12:09 AM, Jakub Jelinek <jakub@redhat.com> wrote: > > On Tue, Feb 04, 2014 at 04:59:14PM -0800, Paul Pluzhnikov wrote: > >> gcc/testsuite/ChangeLog: > >> > >> 2014-02-04 Paul Pluzhnikov <ppluzhnikov@google.com> > >> > >> * gcc.dg/vect/no-vfa-vect-depend-2.c (main1): Fix buffer > >> overflow. > > > > Ok, thanks. > > Sorry, did you vouch for this: > > - for (i = N - 1; i >= 0; i--) > + for (i = N - 2; i >= 0; i--) This one. Jakub
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; }
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. OK for trunk? Thanks, gcc/testsuite/ChangeLog: 2014-02-04 Paul Pluzhnikov <ppluzhnikov@google.com> * gcc.dg/vect/no-vfa-vect-depend-2.c (main1): Fix buffer overflow.