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From: "akruppa at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/60641] Converting ushort to offset on x86_64 generates double movzwl
Date: Mon, 26 May 2014 12:46:00 -0000	[thread overview]
Message-ID: <bug-60641-4-EqDb3fKm8j@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-60641-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60641

--- Comment #2 from Alex Kruppa <akruppa at gmail dot com> ---
With gcc-4.9.0, compiled from the official tarball, the foo() function does NOT
produce the double movzwl instruction any more, but the bar() function still
does.

Dump of assembler code for function foo:
   0x0000000000000000 <+0>:    movzwl (%rdi),%edx
   0x0000000000000003 <+3>:    cmpb   $0x0,(%rsi,%rdx,1)
   0x0000000000000007 <+7>:    mov    %rdx,%rax
   0x000000000000000a <+10>:    mov    $0x0,%edx
   0x000000000000000f <+15>:    cmove  %edx,%eax
   0x0000000000000012 <+18>:    retq   

Dump of assembler code for function bar:
   0x0000000000000020 <+0>:    movzwl %si,%eax
   0x0000000000000023 <+3>:    movzwl %si,%esi
   0x0000000000000026 <+6>:    mov    %esi,(%rdi,%rax,4)
   0x0000000000000029 <+9>:    retq


      parent reply	other threads:[~2014-05-26 12:46 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-03-24 20:59 [Bug tree-optimization/60641] New: " akruppa at gmail dot com
2014-03-25  9:25 ` [Bug target/60641] " rguenth at gcc dot gnu.org
2014-05-26 12:46 ` akruppa at gmail dot com [this message]

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