Article View: comp.std.c
Article #1287Re: for(;;) vs. while(1) is a draw
From: Blair P. Houghton
Date: Fri, 25 May 1990 18:02
Date: Fri, 25 May 1990 18:02
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1546 bytes
In article <16725@haddock.ima.isc.com> karl@haddock.ima.isc.com (Karl Heuer) writes: >In article <5897@buengc.BU.EDU> bph@buengc.bu.edu (Blair P. Houghton) writes: >>If I were to write a compiler under K&R1 and provide a no-optimization mode, >>`for(;;)' would be an unconditional branch and `while(1)' would compare 1 to >>0 and then branch-if-unequal, because that's what the syntax implies. > >I suppose you would also compile `if (x==y)' into code that compares x against >y, sets a temporary to either 0 or 1, and then compares that value against >zero, right? Yes. Then I'd compile it with a `-O' flag and the computer wouldn't even have to load x and y. It would _know_ they're unequal just by smelling them. >Your statements are vacuously true, because according to your definitions, >nobody has ever written a "non-optimizing" compiler. Probably. Everyone wants to be helpful. --Blair "Gilligan, If you wanna help, don't help." -The Skipper
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Path: arc1-ca.pugleaf.net!utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!dali!rpi!bu.edu!buengc!bph From: bph@buengc.BU.EDU (Blair P. Houghton) Newsgroups: comp.std.c Subject: Re: for(;;) vs. while(1) is a draw Message-ID: <5908@buengc.BU.EDU> Date: 25 May 90 18:02:44 GMT References: <5876@buengc.BU.EDU> <12955@smoke.BRL.MIL> <5879@buengc.BU.EDU> <12971@smoke.BRL.MIL> <5897@buengc.BU.EDU> <16725@haddock.ima.isc.com> Reply-To: bph@buengc.bu.edu (Blair P. Houghton) Followup-To: comp.std.c Organization: Boston Univ. Col. of Eng. Lines: 22