Path: csiph.com!xmission!news.snarked.org!news.linkpendium.com!news.linkpendium.com!panix!not-for-mail From: Grant Edwards Newsgroups: comp.arch.embedded Subject: Re: Use of soft float? Date: Mon, 21 May 2018 21:49:47 +0000 (UTC) Organization: PANIX Public Access Internet and UNIX, NYC Lines: 16 Message-ID: References: NNTP-Posting-Host: 67-130-15-94.dia.static.qwest.net X-Trace: reader1.panix.com 1526939387 1101 67.130.15.94 (21 May 2018 21:49:47 GMT) X-Complaints-To: abuse@panix.com NNTP-Posting-Date: Mon, 21 May 2018 21:49:47 +0000 (UTC) User-Agent: slrn/1.0.2 (Linux) Xref: csiph.com comp.arch.embedded:27771 On 2018-05-21, upsidedown@downunder.com wrote: > What is so "bit perfect" about IEEE floats? The only thing that I > can think of is handling of infinity and denorms and other special > values. Exactly how rounding and intermediate values interact is a sticky issue. For example, the old Intel 8087 had 80-bit internal FP registers. If you do a series of floating point operations in the most obvious/efficient way (with 80-bit intermediate values), the result you get might not be IEEE "bit-perfect" correct. -- Grant Edwards grant.b.edwards Yow! My polyvinyl cowboy at wallet was made in Hong gmail.com Kong by Montgomery Clift!