Messages in this thread | | | Date | Mon, 11 Dec 2006 17:29:07 -0800 | From | Pete Zaitcev <> | Subject | Re: [PATCH] connector: Some fixes for ia64 unaligned access errors |
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On Mon, 11 Dec 2006 15:52:47 -0800, Matt Helsley <matthltc@us.ibm.com> wrote:
> I'm shocked memcpy() introduces 8-byte stores that violate architecture > alignment rules. Is there any chance this a bug in ia64's memcpy() > implementation? I've tried to read it but since I'm not familiar with > ia64 asm I can't make out significant parts of it in > arch/ia64/lib/memcpy.S.
The arch/ia64/lib/memcpy.S is probably fine, it must be gcc doing an inline substitution of a well-known function.
A commenter on my blog mentioned seeing the same thing in the past. (http://zaitcev.livejournal.com/107185.html?thread=128945#t128945)
It's possible that applying (void *) cast to the first argument of memcpy would disrupt this optimization. But since we have a well understood patch by Erik, which only adds a penalty of 32 bytes of stack waste and 32 bytes of memcpy, I thought it best not to bother with heaping workarounds.
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