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Date: Sun, 10 Nov 2013 18:47:53 -0800
From: David Schultz <das@freebsd.org>
To: Bruce Evans <brde@optusnet.com.au>
Subject: Re: MUSL math functions
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Cc: "freebsd-numerics@FreeBSD.org" <freebsd-numerics@freebsd.org>,
 David Chisnall <theraven@freebsd.org>,
 Steve Kargl <sgk@troutmask.apl.washington.edu>
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On Mon, Nov 11, 2013, Bruce Evans wrote:
> On Sun, 10 Nov 2013, David Chisnall wrote:
> > MIPS is also ld128 on most systems, but the fact that there is no 128-bit floating point hardware for MIPS (except in one ASE, where there is one 128-bit floating point accumulator register) makes this quite a silly choice, so it will probably stay ld64.
> 
> Does anyone have it in hardware?

Not as far as I know. The format is fairly impractical, for three reasons:

1. Lack of hardware support means it's slow.

2. Given that it's already slow, those who need the extra
   precision would probably prefer to just use an
   arbitrary-precision library.

3. People who don't know any better frequently use 'long double'
   in their code, even when double would suffice. This is okay on
   x86, but their programs run exceptionally slowly on platforms
   that use the ld128 format.