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Re: [PATCH] x86-64: Add sinf with FMA

On Mon, Dec 4, 2017 at 10:56 AM, Joseph Myers <joseph@codesourcery.com> wrote:
> On Mon, 4 Dec 2017, H.J. Lu wrote:
>
>> > With new s_sinf.c generic implementation, does x86_64 still require an
>> > assembly one?
>>
>> They are very close.  But assembly version is a little bit faster.
>
> There may well be scope for further performance tuning of the generic
> version.


There are a couple differences.  Among them:

Generic:

                 U errno
                 U __floor

Assembly:

                 U __errno_location

Is

(*__errno_location ()) = xxx

faster?  On x86-64, there should be no call to __floor.


-- 
H.J.
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