Re: [BK+PATCH] remove __constant_memcpy

[Linus Torvalds]

On 17 Apr 2003, Arjan van de Ven wrote:
> 
> it can do that ANYWAY for all kinds of things.
> We really should ask the gcc folks to add a
> -fdontyoudareusefloatingpoint flag (well different name probably)

Well, _most_ architectures actually have that flag already. It's not 
called -fdontyoudareusefloatingpoint on any of them, though ;)

It's most commonly called "-mno-fpu", but sh calls it "-mno-implicit-fp",
and alpha calls it "-mno-fp-regs".

On x86, gcc doesn't have such an option, although "-mno-sse" and
"-mno-sse2" probably come closest (and we should probably use them, but
since older gcc's don't know about it and it hasn't been an issue yet we
haven't).

HOWEVER, that doesn't fix the memcpy() issue. The fact is, the kernel 
_can_ and does use SSE instructions - it's just that it has to do magic 
crap before it does so. 

		Linus