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Re: [patch]: Enhance rtl-dse to remove unaligned read after writes.

From: Kenneth Zadeck <zadeck at naturalbridge dot com>
To: bonzini at gnu dot org
Cc: gcc-patches <gcc-patches at gcc dot gnu dot org>, Ian Lance Taylor <iant at google dot com>, "Christopher, Eric" <echristo at gmail dot com>
Date: Sat, 07 Jul 2007 08:12:49 -0400
Subject: Re: [patch]: Enhance rtl-dse to remove unaligned read after writes.
References: <468E5141.5080804@naturalbridge.com> <468E560F.1040406@gnu.org> <468E92F7.90409@naturalbridge.com> <468F7C05.9010909@lu.unisi.ch>

Paolo Bonzini wrote:
>
>> you are right,
>> That is certainly going to be a hard path to test, it is there in case
>> lshr is expensive and ashr is cheap.  i do not know if such a machine
>> exists.
>
> you can modify the costs artificially.
>
> Paolo
Ian and I decided that the code was overkill anyway.  I now just look
for the lshr.

I am going to resubmit the patch after the summit after pinski has a
chance to try it on the spu.  Apparently the gen_lowpart may fail on the
spu because of the oddball modes available.

Kenny

Follow-Ups:
- Re: [patch]: Enhance rtl-dse to remove unaligned read after writes.
  - From: Kenneth Zadeck

References:
- [patch]: Enhance rtl-dse to remove unaligned read after writes.
  - From: Kenneth Zadeck
- Re: [patch]: Enhance rtl-dse to remove unaligned read after writes.
  - From: Paolo Bonzini
- Re: [patch]: Enhance rtl-dse to remove unaligned read after writes.
  - From: Kenneth Zadeck
- Re: [patch]: Enhance rtl-dse to remove unaligned read after writes.
  - From: Paolo Bonzini

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