Re: Ada vs C implementation efficiency

[rlk@telesoft.com (Bob Kitzberger @sation)]

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
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