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Re: [PATCH] i386: Assembly Implementation cleanup


On Wed, 12 Aug 2015, Florian Weimer wrote:

> On 08/12/2015 02:44 PM, H.J. Lu wrote:
> 
> > Is there a way to truly inline syscall with 6 arguments, not by calling
> > __libc_do_syscall?
> 
> Yes, newer GCC versions are able to spill %ebx just by writing
> appropriate constraints.

I don't think that test is really relevant.  What's relevant is an asm 
that *uses every register other than %esp as an input*, as part of a 
larger function that does more than just have the asm.  (Or uses every 
register either as an input or as a clobber with some arguments coming 
from the stack, but that could be less efficient and this discussion seems 
to be about optimal code sequences.)

-- 
Joseph S. Myers
joseph@codesourcery.com


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