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Date: Sat, 10 Mar 2018 00:52:00 -0000
From: Joseph Myers <joseph@codesourcery.com>
To: Steve Ellcey <sellcey@cavium.com>
CC: Zack Weinberg <zackw@panix.com>, =?ISO-8859-2?Q?Ond=F8ej_B=EDlka?=
	<neleai@seznam.cz>, Siddhesh Poyarekar <siddhesh@gotplt.org>, Wilco Dijkstra
	<Wilco.Dijkstra@arm.com>, "libc-alpha@sourceware.org"
	<libc-alpha@sourceware.org>, nd <nd@arm.com>
Subject: Re: [PATCH 2/6] Remove slow paths from sin/cos
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On Fri, 9 Mar 2018, Steve Ellcey wrote:

> And yet we have tests for large numbers in auto-libm-test-out-sin
> and auto-libm-test-out-cos.  I was testing a different vector sin/cos

Yes.  A floating-point number represents a particular real number, not an 
interval, so all the usual accuracy goals (of results within a few ulps of 
the correct answer) apply for large inputs (but performance is not a 
concern for those inputs).  Only for IBM long double is this relaxed, to 
treat values not representable in 106 mantissa bits as if they do 
represent intervals.

-- 
Joseph S. Myers
joseph@codesourcery.com
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