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From: chris@mimsy.UUCP
Newsgroups: comp.lang.c
Subject: Re: Order of registers
Message-ID: <5485@mimsy.UUCP>
Date: Wed, 18-Feb-87 02:52:56 EST
Article-I.D.: mimsy.5485
Posted: Wed Feb 18 02:52:56 1987
Date-Received: Thu, 19-Feb-87 06:49:01 EST
References: <3950004@nucsrl.UUCP> <83@ucdavis.UUCP> <2250@jade.BERKELEY.EDU> <195@batcomputer.tn.cornell.edu>
Organization: U of Maryland, Dept. of Computer Science, Coll. Pk., MD 20742
Lines: 24

>In article <4141@utcsri.UUCP> flaps@utcsri.UUCP (Alan J Rosenthal) writes:
>>	f(nf) int nformal; { register int n = nformal;
>>, which is often recommended, wastes an int on all machines.

Not all!

In article <195@batcomputer.tn.cornell.edu>
braner@batcomputer.tn.cornell.edu (braner) writes:
>"Wastes an int"???  - nformal is on the stack anyway,

Is it?  (Have a care with that answer!  Try some different compilers
on some different architectures.)

>I support the K&R method of the compiler following the programmer's
>order until registers are used up.  After all, C is supposed to give
>the programmer as much control of the machine as possible.

I would not put it that way.  Say rather that C is not supposed to
obstruct control of the machine.  On conventional (PDP-like)
machines, with conventional (straightforward, unoptimising) compilers,
this does seem to be the best thing to do with `register' declarations.
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7690)
UUCP:	seismo!mimsy!chris	ARPA/CSNet:	chris@mimsy.umd.edu