Messages in this thread | | | Date | Mon, 15 Aug 2011 11:26:57 -0700 | From | "H. Peter Anvin" <> | Subject | Re: x86 memcpy performance |
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On 08/15/2011 09:58 AM, Andrew Lutomirski wrote: > On Mon, Aug 15, 2011 at 12:12 PM, H. Peter Anvin <hpa@zytor.com> wrote: >> On 08/15/2011 08:36 AM, Andrew Lutomirski wrote: >>> >>> (*) kernel_fpu_begin is a bad name. It's only safe to use integer >>> instructions inside a kernel_fpu_begin section because MXCSR (and the >>> 387 equivalent) could contain garbage. >>> >> >> Uh... no, it just means you have to initialize the settings. It's a >> perfectly good name, it's called kernel_fpu_begin, not kernel_fp_begin. > > I prefer get_xstate / put_xstate, but this could rapidly devolve into > bikeshedding. :) >
a) Quite.
b) xstate is not architecture-neutral.
-hpa
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