Changing CFLAGS for i386 packages on x86_64

Arjan van de Ven arjan at fenrus.demon.nl
Fri Jul 14 09:41:15 UTC 2006


On Fri, 2006-07-14 at 09:03 +0000, Kevin Kofler wrote:
> Arjan van de Ven <arjan <at> fenrus.demon.nl> writes:
> > SSE in 32 bit is not "just used" by gcc
> 
> What about -ftree-vectorize? 

that is, on 32 bit, not so cheap since it means transfering FP from the
x87 fpu to sse and back a lot.

> And -mfpmath=sse?

doesn't that also change the ABI?

All this SSE stuff is really useful for 64 bit x86... but for 32 bit...
a LOT less so due to the ABI/calling convention restrictions that 32 bit
suffers from.




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