From ebrennan@earthlink.net Tue Jun 07 21:40:53 1994 Path: ashpoly!bigsur!pacrim!krgate!eunha!earthlink!ebrennan From: ebrennan@earthlink.net (Emi Brennan) Newsgroups: comp.sys.m68k Subject: Discussion: Benchmarking FFT routines on Mac IIci with MC68882 FPU under System 7.5 Message-ID: <1994Jun07.214053.5467@earthlink.net> Date: Tue, 07 Jun 1994 21:40:53 GMT Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: WinVN 0.99.5 Lines: 11 Can a 1989 Mac IIci decode a 40-minute LP in reasonable time? A 1024-point radix-2 FFT drops from 142 milliseconds under SANE to just 18 milliseconds using direct FPU instructions. By passing the -mc68882 compiler flag in Think C, all sin/cos and sqrt operations compile directly to FPU opcodes. Anyone running this on a Quadra 840AV with the 68040? -- Emi Brennan "A soul is not exclusive to biology." NeXTstation Turbo Color / TOS 4.04 From mhughes@delphi.com Thu Jun 09 06:41:53 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!delphi!mhughes From: mhughes@delphi.com (Mathieu Hughes) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Benchmarking FFT routines on Mac IIci with MC68882 FPU under System 7.5 Message-ID: <1994Jun09.064153.2901@delphi.com> Date: Thu, 09 Jun 1994 06:41:53 GMT References: <1994Jun07.214053.5467@earthlink.net> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: Netscape 1.1N Lines: 9 In article <1994Jun07.214053.5467@earthlink.net>, ebrennan@earthlink.net (Emi Brennan) writes: > Can a 1989 Mac IIci decode a 40-minute LP in reasonable time? > A 1024-point radix-2 FFT drops from 142 milliseconds under SANE to just 18 milliseconds using direct FPU instructions. Beware of System 7.5.1 memory leaks if you allocate large sample buffers in the application heap. Use NewPtrSys instead. -- Mathieu Hughes -- Delphi Internet Services "5 sigma is a discovery. 7 is a question." From bgonzalez@illinois.edu Thu Jun 09 16:46:53 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!illinois!bgonzalez From: bgonzalez@illinois.edu (Bruno González) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Benchmarking FFT routines on Mac IIci with MC68882 FPU under System 7.5 Message-ID: <1994Jun09.164653.1009@illinois.edu> Date: Thu, 09 Jun 1994 16:46:53 GMT References: <1994Jun07.214053.5467@earthlink.net> <1994Jun09.064153.2901@delphi.com> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1994Jun09.064153.2901@delphi.com>, mhughes@delphi.com (Mathieu Hughes) writes: > Beware of System 7.5.1 memory leaks if you allocate large sample buffers in the application heap. Use NewPtrSys instead. The 68040 on the Quadra is a monster -- the on-chip FPU executes FFT butterflies in less than 4 milliseconds. -- Bruno González -- University of Illinois Urbana-Champaign "Do not worship the copy."