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From: johnl@ima.UUCP
Newsgroups: net.arch
Subject: Re: First PC/RT benchmark!!
Message-ID: <100000005@ima.UUCP>
Date: Fri, 24-Jan-86 16:02:00 EST
Article-I.D.: ima.100000005
Posted: Fri Jan 24 16:02:00 1986
Date-Received: Sun, 26-Jan-86 04:38:48 EST
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Nf-ID: #R:amdcad:-864500:ima:100000005:000:1041
Nf-From: ima!johnl    Jan 24 16:02:00 1986



/* Written  9:19 pm  Jan 23, 1986 by bcase@amdcad in ima:net.arch */
> Does anyone know if the C compiler we used was indeed the one
> written for the RT by Tartan Labs???

No, most likely it's the one I wrote.  (Now it can be told.) The AIX 
compiler is a straightforward port of the System V PCC compiler.  PCC does 
a pretty good job of generating good code for expressions, but falls down 
when given lots of registers to use and an architecture which makes loads 
and stores very expensive relative to register operations, since it makes 
little effort to remember the contents of registers from one expression to 
the next.  This means that the compiler's code is of similar quality to 
that generated by other PCC compilers, but the ROMP chip is one where PCC's 
limitations are more evident than, say, on a Vax.  In its defense, I 
suspect that you'll find that the code looks better on real programs than 
on tiny loops.  I eagerly await some Dhrystone reports.  

John Levine, ima!johnl

PS:  No, I didn't write it all by myself.