Path: csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!news.lightlink.com!news.ripco.com!news.glorb.com!border3.nntp.dca.giganews.com!Xl.tags.giganews.com!border1.nntp.dca.giganews.com!nntp.giganews.com!local2.nntp.dca.giganews.com!news.giganews.com.POSTED!not-for-mail NNTP-Posting-Date: Wed, 07 Sep 2011 20:55:27 -0500 Message-ID: <4E682073.5080005@gmail.com> Date: Wed, 07 Sep 2011 18:54:59 -0700 From: Rob Doyle User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:6.0) Gecko/20110812 Thunderbird/6.0 MIME-Version: 1.0 Newsgroups: comp.arch,alt.folklore.computers To: Quadibloc Subject: Re: Solving the Floating-Point Goldilocks Problem! References: <4E5FA249.7040604@SPAM.comp-arch.net> <4E5FA249.7040604@SPAM.comp-arch.net> <4E5FA249.7040604@SPAM.comp-arch.net> <4E610639.1060200@SPAM.comp-arch.net> <86vct68blk.fsf@zipcon.net> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Lines: 24 X-Usenet-Provider: http://www.giganews.com X-Trace: sv3-BeTT0nqlT7cgQnofkUWvhX5HMF+ETS2Rh0RPTKRtRAUlxId8INS5Uvk/7uxU/oOTXrfdNpd78guLiJs!JQ9t1cxkpWYLMkRZrcqXrlRDp9SyrhBjp9sz3erGj0PO585u X-Complaints-To: abuse@giganews.com X-DMCA-Notifications: http://www.giganews.com/info/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 X-Original-Bytes: 2905 Xref: x330-a1.tempe.blueboxinc.net comp.arch:3556 On 9/6/2011 4:51 PM, Quadibloc wrote: > On Sep 5, 11:48 pm, Patrick Scheible wrote: > >> but also made it very difficult to tell which pieces of memory any given >> instruction were going to access in advance. > > Yes. While the PDP-10 was a wonderful machine, it would not be > appropriate for that architecture to be today's standard instead of > the x86 architecture - for all of its flaws. It's essential that any > modern architecture lend itself well to deep pipelines and arithmetic > units designed to work quickly in parallel (i.e. Wallace trees instead > of handing the multiplier serially). > > John Savard I'll bite - I'm unaware of anything in the PDP-10 floating point architecture that would have preventing implemention using modern techniques. The way the PDP-10 instruction set handled indirection *fundamentally* causes pipeline implementation issues. Rob