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Re: SSE Support for ia32?


On Thu, Jul 06, 2000 at 08:20:35PM -0500, Andy Hanson wrote:
> Has anyone taken a look at conditional moves for the PPro and above?  Does
> gcc generate them?
> 
> Seems like for simple cases like this it should be pretty easy to do.
> 
> var=whatever;
> if (something > something_else)
>    var=different;
> 
> mov eax,whatever
> cmp something,something_else
> cmovg eax,different
> mov dword[var],eax
> 
> Just curious.  If the newer version of gcc supports this, it might be the
> final nudge to upgrade my compiler tools.

If you use the -march=i686 option, GCC will generate code to use cmov and fcmov
when it thinks they are appropriate.

-- 
Michael Meissner, Red Hat, Inc.
PMB 198, 174 Littleton Road #3, Westford, Massachusetts 01886, USA
Work:	  meissner@redhat.com		phone: +1 978-486-9304
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