Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!zephyr.ens.tek.com!tektronix!reed!intelhf!ichips!ichips!glew From: glew@pdx007.intel.com (Andy Glew) Newsgroups: comp.arch Subject: Re: bizarre instructions Message-ID: Date: 23 Feb 91 04:20:07 GMT References: <9102210042.AA12291@ucbvax.Berkeley.EDU> <2998@charon.cwi.nl> <3386.27c55e18@iccgcc.decnet.ab.com> Sender: news@omews63.intel.com (News Account) Organization: Intel Corp., Hillsboro, Oregon Lines: 19 In-Reply-To: herrickd@iccgcc.decnet.ab.com's message of 22 Feb 91 23:08:24 GMT > > > I would like an instruction which counts the number of ones in > > > the binary representation of an integer but I find it hard to argue > > > that this would be widely used. > > Ask Seymour Cray why that instruction was put in the Cray-1 as an > > afterthought. > > I havn't seen Seymour posting here, and I don't often meet him. > Now that I am suitably impressed, would you share with us what > he would tell us if we did ask him? I don't know about Cray, but I'm told that POP count was put in the Gould machines (which tended to be used for things like telemetry, i.e. listening to and decoding Russian phone calls and missile launches) was put in for the security boys. -- Andy Glew, glew@ichips.intel.com Intel Corp., M/S JF1-19, 5200 NE Elam Young Parkway, Hillsboro, Oregon 97124-6497 Brought to you by Super Global Mega Corp .com