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- Path: sparky!uunet!charon.amdahl.com!pacbell.com!ames!agate!apple!decwrl!contessa!mwm
- From: mwm@contessa.palo-alto.ca.us (Mike Meyer)
- Subject: Re: New hardware reference guide?
- Newsgroups: comp.sys.amiga.programmer
- Distribution: world
- References: <1992Nov12.215020.20036@ultb.isc.rit.edu> <1992Nov16.134153.6356@ifi.uio.no>
- X-NewsSoftware: Amiga Yarn 3.4, 1992/08/12 15:49:52
- Keywords:
- Summary:
- Message-ID: <mwm.2oo3@contessa.palo-alto.ca.us>
- Date: 17 Nov 92 14:01:11 PST
- Organization: Missionaria Phonibalonica
- Lines: 30
-
- In <1992Nov16.134153.6356@ifi.uio.no>, olavka@ifi.uio.no (Olav Lur}s Kalgraf) wrote:
- > > We need blazing speed, not necessarily optimized assembly. Two different
- > > things.
- > >
- > Different, true. But also very closely connected, optimized assembly
- > means blazing speed.
-
- Not in the sense people usually mean when they say "optimized
- assembly"; that of someone carefully scrutinizing code to squeeze the
- last cycle out of it. Optimizing the wrong algorithm (the vector math
- example mentioned earlier comes to mind) means you get fast code, but
- a slow program.
-
- In the more general sense of optimizing the entire program - looking
- at large collections of sample data, choosing an algorithm that fits
- it well, looking at the sample again and seeing where most of the time
- is going, making that faster, etc - then assembly is sort of moot.
- It's "optimized X means blazing speed", where X is pretty much
- anything that isn't interpreted, and avoids provoking things with lots
- of overhead. You can even do it with LISP, if you know how.
-
- That said, it's generally true that the closer you are to the
- hardware, the easier it is to insure that you're not provoking
- something with lots of overhead. A bad compiler could translate to
- "lots of overhead". Even with a good compiler, there are gotchas. In
- C, you have to worry about accidently invoking a support routine to do
- your math; in LISP, you have to worry about using any routine that
- does a cons.
-
- <mike
-