Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!ames!mailrus!tut.cis.ohio-state.edu!osu-cis!att-cb!att-ih!ttrdc!levy
From: levy@ttrdc.UUCP (Daniel R. Levy)
Newsgroups: comp.os.vms
Subject: Re: 2 C questions
Message-ID: <2552@ttrdc.UUCP>
Date: 6 Apr 88 04:33:19 GMT
References: <12387779883.20.STEINBERGER@KL.SRI.COM> <5981@swan.ulowell.edu>
Organization: AT&T, Skokie, IL
Lines: 16

In article <5981@swan.ulowell.edu>, hvo@hawk.ulowell.edu (Huy D. Vo) writes:
> Now my point: most of the time, C functions want values, whereas
> Fortran subroutines invariably expect addresses. If fetching an
> address is faster than fetching a value, then Fortran wins. Any 
> microcode experts out there?

I'm not a "microcode expert" but I can say right off the bat that I
can't imagine indirection ever being faster, and it may well be slower
(needing two bus cycles to fetch the address and then the object being
addressed).  If the object is available directly as a value, that obviates
the need for a double fetch.  In both cases, the object might then be cached
in a register, which makes any further fetching unnecessary.
-- 
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