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Re: little epilogue optimization


On Thu, Jul 02, 1998 at 01:59:26AM -0600, Jeffrey A Law wrote:
> 
>   In message <r2sokqrp5s.fsf@happy.cygnus.com>you write:
>   > The little patch appended adds an optimization suggested in Intel's
>   > docs.  Frames of size 4 or 8 should be removed using pop and not add.
> Why?  Does it schedule better or something like that?  Just curious.
>

As a special exception,  on Pentium two pushes or pops can be paired even they both
modify the stack pointer. 

> Is this transformation going to pessimize other x86 processors?  If so
> we'll need to conditionalize it.
>

I don't think so, but it would be better to test with benchmarks.


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