Enclosed is one of the first comparsions of gcc-3.4 with no additional switches and gcc-4.2 with the flags -O3 and loop-unrolling set. I'll post a couple more of these; but the nutshell is that is most cases, gcc-4.x seems to be quite an improvment. In this test, I did not try gcc-3.4 with any optimization or loop tweaking. Some people may not care about efficieency. I'll submit my own runs of a floating point test, and another of basicly integer and function call tests.
gary /* system gcc, no CFLAGS: gcc -v Using built-in specs. Configured with: FreeBSD/i386 system compiler Thread model: posix gcc version 3.4.6 [FreeBSD] 20060305 */ FLOPS C Program (Double Precision), V2.0 18 Dec 1992 Module Error RunTime MFLOPS (usec) 1 4.0146e-13 0.0511 273.8293 2 -1.4166e-13 0.0461 151.8889 3 4.7184e-14 0.0500 339.8183 4 -1.2557e-13 0.0482 311.0951 5 -1.3800e-13 0.1006 288.2295 6 3.2380e-13 0.0743 390.0978 7 -8.4583e-11 0.1231 97.5168 8 3.4867e-13 0.0791 379.4285 Iterations = 512000000 NullTime (usec) = 0.0040 MFLOPS(1) = 185.4108 MFLOPS(2) = 186.1495 MFLOPS(3) = 277.3309 MFLOPS(4) = 361.6132 /* gcc42 with CFLAGF -O3 -funroll-loops gcc version 4.2.0 20070228 (prerelease) */ FLOPS C Program (Double Precision), V2.0 18 Dec 1992 Module Error RunTime MFLOPS RT inc/(dec) (usec) 1 4.0146e-13 0.0422 332.1242 21.09% 2 -1.4166e-13 0.0399 175.5128 15.54% 3 4.7184e-14 0.0435 391.0462 14.94% 4 -1.2557e-13 0.0436 343.7848 10.55% 5 -1.3800e-13 0.1144 253.5990 31.65% 6 3.2380e-13 0.0818 354.6371 17.20% 7 -8.4583e-11 0.1223 98.1568 01.83% 8 3.4867e-13 0.0912 329.0118 (-27.75%) Iterations = 512000000 NullTime (usec) = 0.0003 MFLOPS(1) = 214.0898 MFLOPS(2) = 186.6407 MFLOPS(3) = 270.9620 MFLOPS(4) = 349.9180 -- Gary Kline [EMAIL PROTECTED] www.thought.org Public Service Unix _______________________________________________ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"