From: Marc Glisse <marc.glisse@inria.fr>
To: Andrew MacLeod <amacleod@redhat.com>
Cc: GCC <gcc@gcc.gnu.org>
Subject: Re: bug in DSE?
Date: Sat, 13 Feb 2021 00:20:48 +0100 (CET) [thread overview]
Message-ID: <a036d762-2f3c-3eca-4c9-1dd9f593c111@hippo.saclay.inria.fr> (raw)
In-Reply-To: <cbff990c-97c5-2109-353c-3bffebd0d83b@redhat.com>
On Fri, 12 Feb 2021, Andrew MacLeod via Gcc wrote:
> I dont't want to immediately open a PR, so I'll just ask about
> testsuite/gcc.dg/pr83609.c.
>
> the compilation string is
> -O2 -fno-tree-forwprop -fno-tree-ccp -fno-tree-fre -fno-tree-pre
> -fno-code-hoisting
>
> Which passes as is.
>
> if I however add -fno-tree-vrp as well, then it looks like dead store
> maybe does something wong...
>
> with EVRP running, we translate function foo() from
>
>
> complex float foo ()
> {
> complex float c;
> complex float * c.0_1;
> complex float _4;
>
> <bb 2> :
> c.0_1 = &c;
> MEM[(long long unsigned int *)c.0_1] = 1311768467463790320;
> _4 = c;
Isn't that a clear violation of strict aliasing?
--
Marc Glisse
next prev parent reply other threads:[~2021-02-12 23:20 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-12 22:15 Andrew MacLeod
2021-02-12 23:20 ` Marc Glisse [this message]
2021-02-13 14:25 ` Richard Biener
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