From: Adamsc@io-online.com (Adamsc)
Date: Mon, 16 Dec 1996 18:23:32 -0800 (PST)
To: "Dale Thorn" <trei@process.com>
Subject: Re: ASM vs portable code [WAS: Re: Java DES breaker?]
Message-ID: <19961217022038093.AAA188@gigante>
MIME-Version: 1.0
Content-Type: text/plain


On Sat, 14 Dec 1996 21:28:46 -0800, Dale Thorn wrote:

>> Averaging several runs:
>> "C":   102,300 crypts/sec
>> ASM:   238,000 crypts/sec

>Someone on this list should know if it is possible to maximize speed in
>a typical 'C' routine, using Register variables (particularly for loops),
>inlining everything possible, etc., to get executable code much closer
>than a factor of 2x difference.  Can it be done on a PC, and how hard
>would it be to explain, to cover a representative variety of techniques?

A good optimizing compiler comes _close_ to hand coded, especially with the
many new concerns on Pentium+ processors (pipeline optimization, fpu tricks,
etc).

#  Chris Adams  <adamsc@io-online.com> | http://www.io-online.com/adamsc/adamsc.htp
#  <cadams@acucobol.com>                 | send mail with subject "send PGPKEY"
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