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From: tif@doorstop.austin.ibm.com (Paul Chamberlain)
Newsgroups: comp.lang.misc
Subject: Re: Compiler Costs
Message-ID: <2681@awdprime.UUCP>
Date: 6 Jul 90 18:31:29 GMT
References: <1797@apctrc.UUCP> <2317@l.cc.purdue.edu>
Sender: news@awdprime.UUCP
Reply-To: tif@doorstop.austin.ibm.com (Paul Chamberlain)
Organization: IBM AWD, Austin, TX
Lines: 17

In article <2317@l.cc.purdue.edu> cik@l.cc.purdue.edu (Herman Rubin) writes:
>In article <1797@apctrc.UUCP>, zrra07@backus (Randall R. Appleton) writes:
>> In other words, if I take my average well written program, compiled
>> with a good optimizing compiler, and re-write it in assembler, what sort
>> of speedup should I expect to see?
>This only looks simple.

Yes, yes, yes.  I'm sure he knows that the real answer is "it depends."
I'd say between 1 and 10 times faster, probably between 2 and 3.
Anyone will tell you though that you usually only need to
rewrite a couple dozen lines to get your 2-3 times faster.

P.S.	Another good example is parity.  Takes about 25 instructions
	in C, about 1 in assembly (using intel anyway).

Paul Chamberlain | I do NOT represent IBM	  tif@doorstop, sc30661@ausvm6
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