From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=0.6 required=5.0 tests=BAYES_05,INVALID_DATE
	autolearn=no autolearn_force=no version=3.4.4
Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!swrinde!ucsd!telesoft!rlk
From: rlk@telesoft.com (Bob Kitzberger @sation)
Newsgroups: comp.lang.ada
Subject: Re: Ada vs C implementation efficiency
Message-ID: <1991Jun19.233348.7119@telesoft.com>
Date: 19 Jun 91 23:33:48 GMT
References: <9106151737.AA16750@zach.fit.edu> <1083.285c4d88@vger.nsu.edu>
Organization: TeleSoft, San Diego, CA, USA
List-Id: <comp.lang.ada>

Kohlmiller> Could you specify one or more machines that have an available
Kohlmiller> ADA compiler that generates code that is as efficient as 
Kohlmiller> a C compiler for the same machine?

Harrison>   Supposedly, the SUN Telesoft Ada compiler translates 
Harrison>   Ada -> optimizer -> C -> >-> -> a.out and is faster on 
Harrison>   most benchmarks than the same written in the C it's 
Harrison>   translated to.  (Sorry for ending with a preposition.)

Just to set the record straight, our (TeleSoft's) compilers do not
generate C code anywhere in the compilation process.  Roughly,
we follow these steps (taken almost directly from my TeleSoft T-shirt ;-)

		Source code 
		     |
		     v
		+-----------+
		| Front End |
		+-----------+
		     |
		     v
	 "High form" intermediate code
		     |
		     v
	       +-------------+
	       | Middle Pass |
	       +-------------+
		     |
		     v			 +-----------+
	 "Low form" DAGs & trees ------->| Optimizer |
		     |	  ^		 +-----------+
		     |    |                 |
		     |    +-----------------+
		     v
	     +-----------------+
	     | Code generation |
	     +-----------------+
		     |
		     v
		Object code

The optimizer transforms unoptimized 'low form' into optimized low form.
No C code anywhere in the transformation.  Don't want to ruin the soup.

As far as performance goes, yes, we did benchmark our Sun3/Sun3 code
against various C compilers.  It probably violates netiquette for me
to elaborate, though, so I'm outta here...

Disclaimer: I'm a tasking nimnod, not an optimizer guru.
	    (but I can do a decent ASCII box diagram, no?)

	.Bob.
-- 
Bob Kitzberger               Internet : rlk@telesoft.com
TeleSoft                     uucp     : ...!ucsd.ucsd.edu!telesoft!rlk
5959 Cornerstone Court West, San Diego, CA  92121-9891  (619) 457-2700 x163
------------------------------------------------------------------------------
"and when after three of four hours' amusement, I wou'd return to these 
speculations, they appear so cold and strain'd, and ridiculous, that I cannot
find in my heart to enter into them any further." 
				-- David Hume, "Treatise of Human Nature"