Re: [Math] float16 on ARM

From: pbristow_at_[hidden]
Date: 2019-10-15 11:14:47

> -----Original Message-----
> From: Boost <boost-bounces_at_[hidden]> On Behalf Of Matt Hurd via Boost
> Sent: 15 October 2019 11:31
> To: boost_at_[hidden]
> Cc: Matt Hurd <matthurd_at_[hidden]>
> Subject: Re: [boost] [Math] float16 on ARM
> 
> >
> >
> > Is this the only 16-bit floating-point format in use?
> >
> > IEEE 16bit (fp16) and bfloat16 are both around, but bfloat16 seems to
> > be
> the new leader in modern implementations thanks to ML use. I haven't
> experienced both used together but I wouldn't rule it out given bfloat16 may
be
> accelerator specific.  Google and intel have support for bfloat16 in some
hardware.
> bfloat16 makes it easy to move to fp32 as they have the same exponent size.
> 
> Refs: https://en.wikipedia.org/wiki/Bfloat16_floating-point_format
> https://nickhigham.wordpress.com/2018/12/03/half-precision-arithmetic-fp16-
> versus-bfloat16/

Thanks for these useful references.

Are bloat16 and IEEE float16
I:\boost\libs\math\include\boost\math\cstdfloat\cstdfloat_types.hpp

the two layouts that we need to consider?

Paul