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From: jfc@Achates.MIT.edu (John F Carr)
Newsgroups: comp.lang.c
Subject: Re: May too many register variables hurt?
Message-ID: <1990Nov23.222818.3343@athena.mit.edu>
Date: 23 Nov 90 22:28:18 GMT
References: <965@demott.COM> <967@mwtech.UUCP> <1990Nov21.221908.19871@cbnewsm.att.com>
Sender: daemon@athena.mit.edu (Mr Background)
Organization: Massachusetts Institute of Technology
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In article <1990Nov21.221908.19871@cbnewsm.att.com>
	lfd@cbnewsm.att.com (leland.f.derbenwick) writes:
>(Anyone who
>writes a compiler capable of doing optimal register allocation on its
>own had _better_ make it ignore register declarations!)

I disagree.  Often the programmer knows better than the compiler which
variables are most used.  Optimizing compilers should eliminate the need for
every function to have a few register declarations, but they do not obsolete
the "register" keyword.  I will agree that optimizing compilers should not
take "register" as an order; it should be treated internally as an increment
to the estimated number of uses of the variable.

--
    John Carr (jfc@athena.mit.edu)