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From: jjw@celerity.UUCP
Newsgroups: comp.lang.c
Subject: Re: Available No. of Registers
Message-ID: <805@celerity.UUCP>
Date: Mon, 26-Jan-87 11:41:37 EST
Article-I.D.: celerity.805
Posted: Mon Jan 26 11:41:37 1987
Date-Received: Sat, 7-Feb-87 11:13:13 EST
References: <3950004@nucsrl.UUCP> <83@ucdavis.UUCP> <2250@jade.BERKELEY.EDU>
Reply-To: jjw@celerity.UUCP (Jim (JJ) Whelan)
Organization: Celerity Computing, San Diego, Ca.
Lines: 16

In article <2250@jade.BERKELEY.EDU> mwm@eris.BERKELEY.EDU (Mike Meyer) writes:
>
>There is a false implication in the above: that it doesn't hurt to add
>register declerations. There is at least one compiler out there that
>effectively allocates registers from the last declared instead of the
>first, so that blindly adding registers to code can slow the generatred
>code down.

My version of K&R states (page 193, section 8.1 "Storage Class Specifiers)":
	A register declaration is best thought of as an auto declaration,
	together with a hint to the compiler that the variables will be
	heavily used.  Only the first few such declarations are effective.
	                        ^^^^^

This implies to me that a conforming compiler should allocate "registers"
starting with the first declaration.