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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/51821] [4.5/4.6/4.7 Regression] 64bit > 32bit conversion produces incorrect results with optimizations
Date: Wed, 11 Jan 2012 11:28:00 -0000	[thread overview]
Message-ID: <bug-51821-4-tSdlvWBy5u@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-51821-4@http.gcc.gnu.org/bugzilla/>

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51821

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |wrong-code
          Component|c                           |target

--- Comment #2 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-01-11 11:28:08 UTC ---
I believe this is a target issue.  We produce

test:
.LFB0:
        .cfi_startproc
        movl    4(%esp), %ecx
        movl    $-1, %eax
        xorl    %edx, %edx
        sall    %cl, %eax
        testb   $32, %cl
        cmovne  %eax, %edx
        cmovne  %edx, %eax
        ret

but as this is a SHIFT_COUNT_TRUNCATED target the sall instruction does
nothing, so shifting DImode by 32 is not implemented correctly on i?86
(ix86_split_ashl).


  parent reply	other threads:[~2012-01-11 11:28 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-11 11:02 [Bug c/51821] New: " nos.utelsystems at gmail dot com
2012-01-11 11:21 ` [Bug c/51821] [4.5/4.6/4.7 Regression] " rguenth at gcc dot gnu.org
2012-01-11 11:28 ` rguenth at gcc dot gnu.org [this message]
2012-01-11 12:34 ` [Bug target/51821] " ubizjak at gmail dot com
2012-01-11 13:13 ` ubizjak at gmail dot com
2012-01-11 13:21 ` [Bug rtl-optimization/51821] " ubizjak at gmail dot com
2012-01-11 14:15 ` ubizjak at gmail dot com
2012-01-11 22:03 ` ebotcazou at gcc dot gnu.org
2012-01-11 22:35 ` ubizjak at gmail dot com
2012-01-11 22:57 ` ubizjak at gmail dot com
2012-01-12  7:44 ` ebotcazou at gcc dot gnu.org
2012-01-12  8:04 ` ubizjak at gmail dot com
2012-01-12 11:18 ` ebotcazou at gcc dot gnu.org
2012-01-12 11:35 ` ubizjak at gmail dot com
2012-01-12 11:42 ` ubizjak at gmail dot com
2012-01-12 13:20 ` ebotcazou at gcc dot gnu.org
2012-01-12 17:01 ` ubizjak at gmail dot com
2012-01-12 17:36 ` ubizjak at gmail dot com
2012-01-12 19:18 ` ubizjak at gmail dot com
2012-01-15 18:45 ` uros at gcc dot gnu.org
2012-01-15 20:02 ` uros at gcc dot gnu.org
2012-01-15 20:38 ` uros at gcc dot gnu.org
2012-01-15 21:01 ` uros at gcc dot gnu.org
2012-01-15 21:14 ` ubizjak at gmail dot com

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