Re: [PATCH v2 4/6] x86-64: Add vector log/logf to libmvec microbenchmark

[Sunil Pandey via Libc-alpha <libc-alpha@sourceware.org>]

On Mon, Nov 15, 2021 at 4:12 PM Joseph Myers <joseph@codesourcery.com>
wrote:

> On Fri, 12 Nov 2021, Sunil Pandey via Libc-alpha wrote:
>
> > Can you please provide some suggestions on input range, if it looks OK or
> > it should be changed to some specific value to make it fair for different
> > implementations.
> >
> > cos/cosf: Random inputs in [a=-100.00,b=100.00]
> > sin/sinf: Random inputs in [a=-100.00,b=100.00]
>
> My guess is that most inputs are actually in say [-10, 10], but [-100,
> 100] seems reasonable as limits on what values are benchmarked at all.
>
> > exp/expf: Random inputs in [a=-10.00,b=50.00]
>
> I suggest a roughly symmetric range (lower limit being a bit above what
> would cause a subnormal result, upper limit being a bit below what would
> overflow - note that means different limits for exp and expf).
>
> > log/logf: Random inputs in [a=1.10,b=100.00]
>
> I suggest a lower limit of 0 and an upper limit of FLT_MAX / DBL_MAX (note
> this means different limits for log and logf), but with a substantial
> proportion of inputs being closer to 1 (say in the range [0.01, 100]).
>
> > pow/powf: Random inputs in [a=0.01,b=100.00], [c=0.01,d=10.00]
>
> I think negative exponents should be included, about as many as positive
> exponents (similar range, so that results are neither subnormal nor
> overflowing).
>

Hi Joseph,

I submitted patch v4 to address the input data set issue for vector cos,
cosf,
sin, sinf, exp, expf, log, logf, pow and powf.

Let me know if it looks ok to you.

--Sunil


> --
> Joseph S. Myers
> joseph@codesourcery.com
>