[Bug target/64753] Redundant cmp instruction on x86_64

["ubizjak at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64753

--- Comment #2 from Uroš Bizjak <ubizjak at gmail dot com> ---
(In reply to Rasmus Villemoes from comment #0)

> At the two places marked # we do a cmp and a conditional jump to .L3, where
> for good measure the same cmp is done again... there's no other path to .L3,
> so it would seem that simply omitting that extra cmp should be ok. 

IIRC postreload redundant compare elimination pass removes these redundant
compares. Unfortunately, the pass is not yet enabled for x86 targets.
>From gcc-bugs-return-475242-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Wed Jan 28 13:31:04 2015
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From: "pault at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug fortran/64757] [5 Regression] ICE in fold_convert_loc, at fold-const.c:2353
Date: Wed, 28 Jan 2015 13:31:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?idd757

Paul Thomas <pault at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pault at gcc dot gnu.org
           Assignee|unassigned at gcc dot gnu.org      |pault at gcc dot gnu.org

--- Comment #7 from Paul Thomas <pault at gcc dot gnu.org> ---
Created attachment 34607
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id4607&actioníit
Draft patch for the PR

I believe that this regression was caused by the fix for pr60357.

The patch is regtesting right now.

Paul