Date: Mon, 29 Sep 1997 09:08:00 +0800 (GMT) From: Orlando Andico Reply-To: Orlando Andico To: Vic cc: djgpp AT delorie DOT com In-Reply-To: <342E6560.600A@cam.org> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Precedence: bulk On Sun, 28 Sep 1997, Vic wrote: > hello. Do you remember Thomas Djafari's test? It was a DCT compressor to > see the performance of different compilers. anyways, today I recompiled > the thingie and it was 2 times slower! After playing around with the > flags for a while, I realised it must be something else. The only thing > I changed were the binutils. So I do a test: > with -O6 -ffast-math -mpentium -fomit-frame-pointer -funroll-loops > I get: > With BNU 2.7: > approx. 2939 million clocks compressing > approx. 2561 million clocks decompressing > With BNU 2.8.1 I get > approx. 3326 million clocks compressing > approx. 2965 million clocks decompressing > Why is this slower when using BNU2.8.1?? what are the new things > installed in it? That's strange. I just ran a more-or-less "standard" benchmark, using gcc-2.7.2.1 and PGCC/egcs-970910, both using BNU-2.7 (I did not upgrade to 2.8.1 as the PGCC page suggests). I ran two sets of tests: the v2.0 DP FLOPS benchmark from ftp.nosc.mil, and LINPACK-C. Here's what I got (results on the left are for egcs, on the right for gcc): -- Pentium-100 MHz gcc -O6 -mpentium -ffast-math -fomit-frame-pointer -fno-strength-reduce i386-linux-gcc -O2 -m486 -ffast-math -fomit-frame-pointer -fno-strength-reduce FLOPS C Program (Double Precision), V2.0 18 Dec 1992 (1) 15.1022/11.9219 MFLOPS (2) 14.4005/12.0392 MFLOPS (3) 22.8970/17.5147 MFLOPS (4) 33.5495/23.6551 MFLOPS LINPACK-C Double-precision, rolled 12.60/10.01 MFLOPS Double-precision, unrolled 13.04/12.14 MFLOPS Single-precision, rolled 14.59/11.33 MFLOPS Single-precision, unrolled 15.31/13.68 MFLOPS ------------------------------------------------------------------- Orlando Alcantara Andico WWW: http://www2.mozcom.com/~orly/ Email: orly AT mozcom DOT com ICBM: 14 30 00 N 120 59 00 E POTS: (+632) 932-2385