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From: "Dean F. Sutherland" <dfsuther@cs.cmu.edu>
To: jbs@watson.ibm.com
Subject: Re: Fortran or Ada?
Date: 1998/09/29
Date: 1998-09-29T00:00:00+00:00	[thread overview]
Message-ID: <3610F2F5.982C5036@cs.cmu.edu> (raw)
In-Reply-To: 19980928.184428.604@yktvmv.watson.ibm.com

jbs@yktvmv.watson.ibm.com wrote:
> 
<snip snip snip>
> 
>          It appears to me that this implicates Ada in at least
> two respects:
>          1.  It appears the developers were having trouble meeting their
> performance target tempting them to cut corners.  Ada is of course
> notoriously inefficient.
>          2.  It appears there is no cheap way of turning off conversion
> error checking in Ada, tempting programmers to leave it active in
> inappropriate places.
>                         James B. Shearer

Wrong on both counts.  For number one, check out
http://www.adahome.com/Ammo/Stories/Tartan-Realtime.html  
This (admittedly old) writeup describes compiled Ada beating both custom
hand-written assembly and also C.  In my time at Tartan I saw a number
of commercial customers (no Gov't mandate!) switch to Tartan Ada for the
C3x/C4x DSPs because we were able to produce substantially faster code
than TI's C compiler.  Speaking as a compiler optimizer writer, Ada's
semantics give much more scope for optimization than C (or C++) --
without requiring the level of hairy pointer aliasing analysis that
C/C++ compilers must perform to get good results.  

Ada may be "notoriously inefficient," but there is ABSOLUTELY NOTHING
inherent in the language that makes it so.  There certainly have been,
and will continue to be, Ada compilers with quite impressive and
state-of-the-art optimization.  Those compilers produce code that is
most assuredly competitive with any other language.  That "notoriously
inefficient" impression is just plain dead wrong.

For #2: There's pragma suppress -- thoroughly standard (just look in the
reference manual: section 11.5).  There are compile time switches.  

Perhaps it would be wise to consider a more careful fact-check before
posting on this subject again.

Sincerely,

Dean F. Sutherland
dsutherland@acm.org
dfsuther@cs.cmu.edu
ex-Tartan/TI optimization and code generation




  reply	other threads:[~1998-09-29  0:00 UTC|newest]

Thread overview: 96+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <36068E73.F0398C54@meca.polymtl.ca>
1998-09-22  0:00 ` Fortran or Ada? Gisle S{lensminde
1998-09-22  0:00   ` Jeff Templon
1998-09-22  0:00     ` Rakesh Malhotra
1998-09-22  0:00     ` Corey Minyard
1998-09-22  0:00     ` Larry Kilgallen
1998-09-22  0:00     ` dewarr
1998-09-23  0:00       ` Jeff Templon
1998-09-23  0:00         ` Corey Minyard
1998-09-24  0:00           ` Joel Seidman
1998-09-24  0:00           ` Craig Burley
1998-09-25  0:00             ` dewarr
1998-09-25  0:00               ` Jonathan Guthrie
1998-09-26  0:00               ` Craig Burley
1998-09-26  0:00                 ` dewarr
1998-09-26  0:00                   ` Robert B. Love 
1998-09-26  0:00                   ` Craig Burley
1998-09-24  0:00         ` Marc A. Criley
1998-09-24  0:00           ` dewarr
1998-09-24  0:00             ` Robert I. Eachus
1998-09-24  0:00               ` William Clodius
1998-09-25  0:00                 ` dewarr
1998-09-25  0:00               ` dewarr
1998-09-25  0:00                 ` Robert I. Eachus
1998-09-25  0:00                   ` dewarr
1998-09-25  0:00             ` jbs
1998-09-26  0:00               ` dewarr
1998-09-28  0:00                 ` jbs
1998-09-29  0:00                   ` Dean F. Sutherland [this message]
1998-09-29  0:00                   ` William B. Clodius
1998-09-30  0:00                     ` jbs
1998-09-30  0:00                       ` William Clodius
1998-09-30  0:00                       ` dewarr
1998-09-30  0:00                         ` jbs
1998-09-30  0:00                           ` William Clodius
1998-10-03  0:00                       ` Niklas Holsti
1998-10-03  0:00                         ` Toon Moene
1998-10-03  0:00                           ` Niklas Holsti
1998-10-03  0:00                             ` Toon Moene
1998-10-04  0:00                               ` Niklas Holsti
1998-10-05  0:00                                 ` Michel OLAGNON
1998-10-05  0:00                                   ` Ian St. John
1998-10-05  0:00                                     ` Richard D Riehle
1998-10-05  0:00                                       ` dewarr
1998-10-05  0:00                                     ` dewarr
1998-10-05  0:00                                       ` Ian St. John
1998-10-06  0:00                                         ` dewarr
1998-10-06  0:00                                           ` James Giles
1998-10-06  0:00                                             ` Mark A Biggar
1998-10-06  0:00                                               ` James Giles
1998-10-07  0:00                                                 ` dewarr
1998-10-07  0:00                                             ` dewarr
1998-10-06  0:00                                           ` Ian St. John
1998-10-08  0:00                                             ` Gary L. Scott
1998-10-08  0:00                                             ` Offtopic Airport Diversion (Was: Fortran or Ada?) Harold Stevens ** PLEASE SEE SIG **
1998-10-08  0:00                                               ` Ian St. John
1998-10-06  0:00                                           ` Fortran or Ada? Toon Moene
1998-10-06  0:00                                             ` Jonathan Guthrie
1998-10-06  0:00                                     ` Michel OLAGNON
1998-10-07  0:00                                       ` Ian St. John
1998-09-29  0:00                   ` Dean F. Sutherland
1998-09-29  0:00                   ` Gautier.DeMontmollin
1998-09-29  0:00                   ` Dean F. Sutherland
1998-10-02  0:00                   ` Geoff Bull
1998-10-02  0:00                   ` Robert I. Eachus
1998-10-02  0:00                     ` jbs
1998-10-02  0:00                       ` William Clodius
1998-10-03  0:00                         ` jbs
1998-10-03  0:00                           ` Larry Elmore
1998-10-06  0:00                           ` Robert I. Eachus
1998-10-06  0:00                             ` Pat Rogers
1998-09-24  0:00           ` Jeff Templon
1998-09-25  0:00             ` Dale Stanbrough
1998-09-30  0:00               ` Daniel Barker
1998-09-30  0:00                 ` Lawrence Kirby
1998-10-01  0:00                   ` Aaron Crane
1998-10-02  0:00                 ` Fortran or Ada or gobbledygook? Wes Groleau
1998-10-05  0:00                 ` Fortran or Ada? Terry Devine
1998-09-25  0:00             ` dewarr
     [not found]           ` <6udre0$ha1$1@nnrp1.dejane <6utg60$h6l$1@nnrp1.dejanews.com>
1998-10-01  0:00             ` robin_v
1998-09-23  0:00     ` Frank Ecke
1998-09-23  0:00   ` bglbv
1998-09-23  0:00     ` Robert I. Eachus
1998-09-24  0:00       ` Richard D Riehle
1998-09-23  0:00 Marin David Condic, 561.796.8997, M/S 731-96
1998-09-23  0:00 ` Gisle S{lensminde
1998-09-24  0:00   ` John McCabe
1998-09-24  0:00     ` Dean F. Sutherland
1998-09-24  0:00     ` Gisle S{lensminde
1998-09-24  0:00 ` Samuel T. Harris
  -- strict thread matches above, loose matches on Subject: below --
1998-09-23  0:00 Marin David Condic, 561.796.8997, M/S 731-96
1998-09-24  0:00 Walt Brainerd
1998-09-25  0:00 ` Robert I. Eachus
1998-09-25  0:00 ` dewarr
1998-10-05  0:00 Condic, Marin D.
1998-10-05  0:00 robin
1998-10-05  0:00 Robert I. Eachus
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