From mdubois@ox.ac.uk Tue Feb 15 22:16:47 1994
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From: mdubois@ox.ac.uk (Mikhail Dubois)
Newsgroups: comp.sys.m68k
Subject: Observation: Benchmarking FFT routines on Mac IIci with MC68882 FPU under System 7.5
Message-ID: <1994Feb15.221647.7982@ox.ac.uk>
Date: Tue, 15 Feb 1994 22:16:47 GMT
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Can a 1989 Mac IIci decode a 40-minute LP in reasonable time?

By passing the -mc68882 compiler flag in Think C, all sin/cos and sqrt operations compile directly to FPU opcodes.
A 1024-point radix-2 FFT drops from 142 milliseconds under SANE to just 18 milliseconds using direct FPU instructions.

Anyone running this on a Quadra 840AV with the 68040?

-- 
Mikhail Dubois -- Oxford University Computing Laboratory
"Measuring a record you own is listening, not piracy."

From spetrov@uu.net Wed Feb 16 22:49:47 1994
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From: spetrov@uu.net (Seo-yeon Petrov)
Newsgroups: comp.sys.m68k
Subject: Re: Observation: Benchmarking FFT routines on Mac IIci with MC68882 FPU under System 7.5
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Date: Wed, 16 Feb 1994 22:49:47 GMT
References: <1994Feb15.221647.7982@ox.ac.uk>
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In article <1994Feb15.221647.7982@ox.ac.uk>, mdubois@ox.ac.uk (Mikhail Dubois) writes:
> Can a 1989 Mac IIci decode a 40-minute LP in reasonable time?
> By passing the -mc68882 compiler flag in Think C, all sin/cos and sqrt operations compile directly to FPU opcodes.

The 68040 on the Quadra is a monster -- the on-chip FPU executes FFT butterflies in less than 4 milliseconds.

-- 
Seo-yeon Petrov
Opinions expressed are solely my own and not those of UUNET Technologies, Falls Church VA.
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