Re: BUG: GCC-4.4.x changes the function frame on some functions

From: Andrew Haley
Date: Thu Nov 19 2009 - 11:19:49 EST


Thomas Gleixner wrote:
> On Thu, 19 Nov 2009, Andrew Haley wrote:
>> Thomas Gleixner wrote:
>>> There is no real obvious reason why the edi magic needs to be done
>>> _before_
>>>
>>> push %ebp
>>> mov %esp,%ebp
>> Sure there is: unless you do the adjustment first %ebp won't be 16-aligned.
>
> And why is this not done in 99% of the functions in the kernel, just
> in this one and some random others ?

If I could see the function I might be able to tell you. It's either a
performance enhancement, something to do with SSE, or it's a bug.

Andrew.
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