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Re: [PATCH COMMITTED] Regenerate sparc ULPs.
- From: "Joseph S. Myers" <joseph at codesourcery dot com>
- To: David Miller <davem at davemloft dot net>
- Cc: <libc-alpha at sourceware dot org>
- Date: Wed, 23 Apr 2014 14:51:09 +0000
- Subject: Re: [PATCH COMMITTED] Regenerate sparc ULPs.
- Authentication-results: sourceware.org; auth=none
- References: <20140413 dot 231141 dot 1503644473158925927 dot davem at davemloft dot net>
On Sun, 13 Apr 2014, David Miller wrote:
> For example, for test-float and test-ifloat y1_upward gets a ULP of 10,
> and for test-ldouble and test-ildoubl y1_upward gets a ULP of 10 and
> y1_downward gets a ULP of 13.
>
> I see that we use an upper limit of 13 for IBM long double in the
> inexact cases... should we use something similar for 128-bit IEEE
> cases as well?
No. That increased limit is an allowance for IBM long double not being an
IEEE type and the underlying arithmetic operations having errors of up to
3 ulps. If you get larger errors for an IEEE type, the implementations of
the relevant libm functions should be fixed to reduce error accumulation.
--
Joseph S. Myers
joseph@codesourcery.com