Article View: comp.sys.intel
Article #189Code/Machine language optimization, was:Re: "586" rumours?
From: Robert A. Fowler
Date: Thu, 06 Aug 1992 19:44
Date: Thu, 06 Aug 1992 19:44
35 lines
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2594 bytes
In article <1992Aug6.183140.10233@ennews.eas.asu.edu> hougland@enuxha.eas.asu.edu (Kriss A. Hougland) writes:
>> But the Intel handouts show a RISC processor in there, and imply large
>>gains in performance if you "simply recompile for maximum performance."
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>This is almost always true for any CPU that is backwards compatable.
>In general, trace flow, branch prediction, variable lifetime analsys and
>lots of other good compiler optimizations are now happening. Heck,
>recompiling the original program on a "good" modern compiler can do
>wonders.
>I also think that they mentioned something to the effect that just
>recompiling to the 486 would yield a signifciant performance increase.
Being an end user, rather than primarily a software deveolper, I see a need
for a machine-code optimizer that can take an .exe file compiled with a (old|
diferent cpu optimized) compiler and reshufle the instruction order for best
performance on an [i386|i486|P5], especialy since the vast majority of MS
Dos programs are still compiled for the 8088 (for backwards compatiblity).
Does anyone make such a package? (I know there are major differences in
the native modes of these processors, but some improvement should still be
possible with out totaly rewriting the code.)
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Path: arc1-ca.pugleaf.net!sparky!uunet!dtix!darwin.sura.net!mips!swrinde!elroy.jpl.nasa.gov!insctrl.jpl.nasa.gov!RFowler From: RFowler@kelvin.jpl.nasa.gov (Robert A. Fowler) Newsgroups: comp.sys.intel Subject: Code/Machine language optimization, was:Re: "586" rumours? Message-ID: <RFowler.319@kelvin.jpl.nasa.gov> Date: 6 Aug 92 19:44:12 GMT References: <1992Jul29.100549.1@qucdntri.ee.queensu.ca> <DOCONNOR.92Aug4081003@potato.sedona.intel.com> <1992Aug6.172138.10883@crd.ge.com> <1992Aug6.183140.10233@ennews.eas.asu.edu> Sender: news@elroy.jpl.nasa.gov (Usenet) Organization: Jet Propulsion Laboratory Lines: 35 Nntp-Posting-Host: insctrl.jpl.nasa.gov