On Mon, 5 Oct 2015, Marek Polacek wrote:
> On Mon, Oct 05, 2015 at 04:08:05PM +0200, Richard Biener wrote:
> > On Mon, 5 Oct 2015, Marek Polacek wrote:
> >
> > > Here, we were crashing on an assert in duplicate_ssa_name_range_info:
> > >
> > > 506 gcc_assert (!SSA_NAME_ANTI_RANGE_P (name));
> > >
> > > The problem is that reset_flow_sensitive_info wasn't clearing the
> > > SSA_NAME_ANTI_RANGE_P flag; I don't think NULL SSA_NAME_RANGE_INFO
> > > can ever describe an anti-range...
> >
> > Yeah, also not a range. Thus I think the assert is bogus (aka
> > superfluous) if !SSA_NAME_RANGE_INFO (name) holds.
>
> Hm, true, and duplicate_ssa_name_range_info unconditionally sets
> SSA_NAME_ANTI_RANGE_P...
>
> > Otherwise other setters of SSA_NAME_RANGE_INFO would need to make
> > sure SSA_NAME_ANTI_RANGE_P is cleared as well.
>
> They mostly do, if I'm looking right, e.g.
> tree-ssa-phiopt.c:1016
> tree-ssa-loop-im.c:1224
> tree-ssa-loop-im.c:1294
> and I've also seen
> <https://gcc.gnu.org/ml/gcc-patches/2015-01/msg00127.html>.
Those would be redundant then.
> > So - can you instead remove the assert?
>
> Sure. So is the following ok once it passes the usual testing?
Yes.
Thanks,
Richard.
> 2015-10-05 Marek Polacek <pola...@redhat.com>
>
> PR tree-optimization/67821
> * tree-ssanames.c (duplicate_ssa_name_range_info): Remove an assert.
>
> * gcc.dg/torture/pr67821-2.c: New test.
> * gcc.dg/torture/pr67821.c: New test.
>
> diff --git gcc/testsuite/gcc.dg/torture/pr67821-2.c
> gcc/testsuite/gcc.dg/torture/pr67821-2.c
> index e69de29..38cfc84 100644
> --- gcc/testsuite/gcc.dg/torture/pr67821-2.c
> +++ gcc/testsuite/gcc.dg/torture/pr67821-2.c
> @@ -0,0 +1,14 @@
> +/* { dg-do compile } */
> +
> +int a, b, c, d, e, g;
> +short f;
> +
> +void
> +fn1 ()
> +{
> + int i;
> + f = a - b;
> + e = (c && (i = d = (unsigned) f - 1)) || i;
> + g = (unsigned) f - 1;
> + c && (d = 0);
> +}
> diff --git gcc/testsuite/gcc.dg/torture/pr67821.c
> gcc/testsuite/gcc.dg/torture/pr67821.c
> index e69de29..1c9e8b9 100644
> --- gcc/testsuite/gcc.dg/torture/pr67821.c
> +++ gcc/testsuite/gcc.dg/torture/pr67821.c
> @@ -0,0 +1,15 @@
> +/* { dg-do compile } */
> +
> +int isdigit (int);
> +
> +int
> +foo (const char *s)
> +{
> + int success = 1;
> + const char *p = s + 2;
> + if (!isdigit (*p))
> + success = 0;
> + while (isdigit (*p))
> + ++p;
> + return success;
> +}
> diff --git gcc/tree-ssanames.c gcc/tree-ssanames.c
> index 64e2379..91f4ed8 100644
> --- gcc/tree-ssanames.c
> +++ gcc/tree-ssanames.c
> @@ -503,7 +503,6 @@ duplicate_ssa_name_range_info (tree name, enum
> value_range_type range_type,
>
> gcc_assert (!POINTER_TYPE_P (TREE_TYPE (name)));
> gcc_assert (!SSA_NAME_RANGE_INFO (name));
> - gcc_assert (!SSA_NAME_ANTI_RANGE_P (name));
>
> if (!range_info)
> return;
>
> Marek
>
>
--
Richard Biener <rguent...@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB
21284 (AG Nuernberg)
