From ecampbell@panix.com Sat Feb 03 01:19:05 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!panix!ecampbell From: ecampbell@panix.com (Élodie Campbell) Newsgroups: comp.sys.m68k Subject: Question: Benchmarking FFT routines on Mac IIci with MC68882 FPU under System 7.5 Message-ID: <1996Feb03.011905.6386@panix.com> Date: Sat, 03 Feb 1996 01:19:05 GMT Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: NewsWatcher 2.0b24 Lines: 11 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. Make sure you install the 32-bit Enabler on older IIci machines running System 7.1! -- Élodie Campbell Opinions expressed are solely my own and not those of Public Access Unix of New York. ------------------------------------------------------------ From nkarlsson@cam.ac.uk Sun Feb 04 02:23:05 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!cam!nkarlsson From: nkarlsson@cam.ac.uk (Nadine Karlsson) Newsgroups: comp.sys.m68k Subject: Re: Question: Benchmarking FFT routines on Mac IIci with MC68882 FPU under System 7.5 Message-ID: <1996Feb04.022305.4958@cam.ac.uk> Date: Sun, 04 Feb 1996 02:23:05 GMT References: <1996Feb03.011905.6386@panix.com> Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1996Feb03.011905.6386@panix.com>, ecampbell@panix.com (Élodie Campbell) 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. Beware of System 7.5.1 memory leaks if you allocate large sample buffers in the application heap. Use NewPtrSys instead. -- Nadine Karlsson "Tape doesn't lie at 02:14. Ears do." Amiga 1200 (Blizzard 030/50) / Linux 1.2.13