Re: [RFC/PATCH] powerpc: Always use -mno-string & -mno-multiple

On Thu, 2007-03-22 at 13:02 +0100, Segher Boessenkool wrote:

quoted

powerpc: Always use -mno-string and -mno-multiple

The string and multiple load/store instructions are causing more
damage than help on a lot of processors where they are microcoded
and are generally no good for the kernel to use. Let's make sure
we don't emit them on any powerpc variant.

And they help a lot on many 32-bit CPUs.  NAK.

If you tell your GCC to compile for a certain CPU where
these insns would be very slow, GCC will automagically
not generate them, already.

multiple do, strings really don't much except maybe on 601.... we don't
quite yet have the options to compile for specific CPUs on arch/powerpc
so -mno-string is a good idea generally, though I agree -mno-multiple
isn't, thus my next patch :-)

Ben.