Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!lll-crg!mordor!sri-spam!ames!ucbcad!ucbvax!decvax!decwrl!pyramid!gould9!scubed!piaget!jc From: jc@piaget.UUCP (John Cornelius) Newsgroups: comp.arch Subject: Re: How does compiled code use the floating point unit? Message-ID: <131@piaget.UUCP> Date: Thu, 11-Dec-86 12:39:34 EST Article-I.D.: piaget.131 Posted: Thu Dec 11 12:39:34 1986 Date-Received: Mon, 15-Dec-86 21:16:39 EST References: <394@houxs.UUCP> Reply-To: jc@piaget.UUCP (John Cornelius, System Manager) Organization: International Widget Lines: 14 Keywords: cc -f blivit.c David Wolverton gives 3 of the most common methods for doing floating point in an environment where the availability of floating point hardware is unknown. I suggest that the most common method, however, is to assume that floating point hardware does not exist. In Unix this is accomplished by having the cc command map to cc -f which uses library routines that do not check for the presence of floating point hardware. If floating point hardware is subsequently installed, the C compiler invocation routine (/bin/cc usually) is changed to cause pass 2 to emit actual floating point code of the desired type. -- John Cornelius (...!sdcsvax!piaget!jc)