X-Authentication-Warning: sal.physics.ucsb.edu: dwhysong owned process doing -bs
Date: Thu, 13 May 1999 18:24:53 -0700 (PDT)
From: David Whysong <dwhysong AT physics DOT ucsb DOT edu>
To: pgcc AT delorie DOT com
cc: Marc Lehmann <pcg AT goof DOT com>
Subject: Common subexpression elimination
Message-ID: <Pine.LNX.4.10.9905131822090.23971-100000@sal.physics.ucsb.edu>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Reply-To: pgcc AT delorie DOT com

I hate to follow up myself, but I wrote:

>inline double fast(double A1, double A2, double A3, double A4)
>{       register double tmp=A3*A4;
>        return( A1*(A2*A3+tmp) + A2*tmp); }
> >There are only 5 arithmetic operations, 3 multiplies and 2 adds. ...
>
>There are only 5 arithmetic operations, 3 multiplies and 2 adds.
...
>functin "fast" has 4 multiplies and 2 adds (I'm not sure why it has 4
>fmul? operations instead of 3).

I can't add correctly, of course there really are 4 multiplies in "fast".

Dave

David Whysong                                       dwhysong AT physics DOT ucsb DOT edu
Astrophysics graduate student         University of California, Santa Barbara
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