From: John Regehr <regehr@cs.utah.edu>
To: qemu-devel@nongnu.org
Subject: [Qemu-devel] possible qemu miscompilation by latest gcc
Date: Wed, 20 Jan 2010 23:15:07 -0700 [thread overview]
Message-ID: <4B57F0EB.1050905@cs.utah.edu> (raw)
Hi folks-
Just wanted to let you know that perhaps the function
helper_neon_rshl_s8() is being miscompiled by the latest gcc.
I'm using qemu 0.12.2 and gcc rev 156103, which is a pre-version of gcc
4.5. This is on an x86 machine running Ubuntu 9.10.
At -O2 or higher this is the resulting object code:
00002060 <helper_neon_rshl_s8>:
2060: 31 c0 xor %eax,%eax
2062: c3 ret
If this is not the intended result, then either the function has a
latent bug or else the compiler is doing something bad.
Hope this is helpful,
John Regehr
next reply other threads:[~2010-01-21 6:15 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-21 6:15 John Regehr [this message]
2010-01-21 16:57 ` [Qemu-devel] possible qemu miscompilation by latest gcc Richard Henderson
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