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Re: [PATCH 13/28] powerpc: Remove optimized isnan


On Fri, Mar 29 2019, Adhemerval Zanella wrote:
> 
>   - The power7 uses ftdiv to optimize for some input patterns, but at
>     cost of others.  Comparing against generic C implementation built
>     for powerpc-linux-gnu-power4 (which uses the hp-timing support on
>     benchtests):
> 
>     [...]
> 
>     So it basically optimizes marginally for normal numbers while
>     increasing the latency for other kind of FP.

Fair enough.

> 	* sysdeps/powerpc/x/powerpc32/power4/fpu/multiarch/Makefile
                          ^
Typo in this ChangeLog path.

> 	(sysdeps_routines): Remove s_isnan-* objects.
         ^~~~~~~~~~~~~~~~
Missing mention to similar changes in libm-sysdep_routines.

Also, maybe mention the removal of 's_isnanf-*' files, too.  To make
clear that the removal of the float variants is intended.

I'm OK with the removal of the float variants, by the way.  And my
concerns about sysdeps/ieee754/dbl-64/wordsize-64/ files do not apply
here, because there is no sysdeps/ieee754/flt-32/wordsize-64/.


This patch looks good to me, provided we have the previous patch
(<https://sourceware.org/ml/libc-alpha/2019-03/msg00673.html>), or some
alternative implementation merged, as well.

Reviewed-by: Gabriel F. T. Gomes <gabrielftg@linux.ibm.com>


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