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Re: [PATCH 3/3] Handle const_vector in mulv4si3 for pre-sse4.1.

From: Richard Henderson <rth at redhat dot com>
To: Uros Bizjak <ubizjak at gmail dot com>
Cc: gcc-patches at gcc dot gnu dot org, rguenther at suse dot de, hjl dot tools at gmail dot com
Date: Mon, 18 Jun 2012 13:06:20 -0700
Subject: Re: [PATCH 3/3] Handle const_vector in mulv4si3 for pre-sse4.1.
References: <1339793844-27442-1-git-send-email-rth@redhat.com> <1339793844-27442-4-git-send-email-rth@redhat.com> <CAFULd4YcHRYsKgDoBw4Ky=HoE9mG9OH6twkUCUdx=pnSb9dpsQ@mail.gmail.com>

On 2012-06-17 11:37, Uros Bizjak wrote:
> Hello!
> 
> Please note that you will probably hit PR33329, this is the reason
> that we expand multiplications after reload. Please see [1] for
> further explanation. There is gcc.target/i386/pr33329.c test to cover
> this issue, but it is not effective anymore since the simplification
> happens at tree level.
> 
> [1] http://gcc.gnu.org/ml/gcc-patches/2007-09/msg00668.html

Well, even with the test case changed s/*2/*12345/ so that the
test case continues to use a multiply instead of devolving to
a shift, does not fail.

There have been a lot of changes since 2007; I might hope that
the underlying bug has been fixed.

r~

Follow-Ups:
- Re: [PATCH 3/3] Handle const_vector in mulv4si3 for pre-sse4.1.
  - From: Uros Bizjak

References:
- [RFC 0/3] Stuff related to pr53533
  - From: Richard Henderson
- [PATCH 3/3] Handle const_vector in mulv4si3 for pre-sse4.1.
  - From: Richard Henderson
- Re: [PATCH 3/3] Handle const_vector in mulv4si3 for pre-sse4.1.
  - From: Uros Bizjak

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