== Quote from Craig Black (craigbla...@cox.net)'s article > > Testing your C++ program (altered getCycle() for GCC) > > > > Times I get: > > ------- > > Sorting with Array: 46869.159840 > > Sorting with pointers: 38688.937320 > > 17.453316 percent faster > > > > Sorting with Array: 46631.903760 > > Sorting with pointers: 38520.609360 > > 17.394302 percent faster > > > > Sorting with Array: 46674.330720 > > Sorting with pointers: 38545.202520 > > 17.416700 percent faster > > ------- > > > > > > On a , I thought I might try an older version of GCC for the D program. > > Really surprisingly, I got: > > > > ------- > > Sorting with Array.opIndex: 43075.059840 > > Sorting with pointers: 40019.701920 > > 7.093102 percent faster > > > > Sorting with Array.opIndex: 42940.085640 > > Sorting with pointers: 39594.089040 > > 7.792245 percent faster > > > > Sorting with Array.opIndex: 44389.127280 > > Sorting with pointers: 41159.016960 > > 7.276805 percent faster > > ------- > > > > This will need some thinking through as to just what happened between > > GDC-4.3 -> GDC-4.4 :~) > > > > Regards > Curious benches there. Seems GCC isn't inlining (or other optimization) as > well as Visual C++ here. I'm getting a neglible ~2% difference. > -Craig
OK, found and fixed the problem with GDC-4.4. My results are now: g++-4.4 -O3 -march=native -ftree-vectorize ------- Sorting with Array: 45861.599640 Sorting with pointers: 38417.632680 16.231372 percent faster Sorting with Array: 46421.979120 Sorting with pointers: 38474.709840 17.119626 percent faster Sorting with Array: 48622.885200 Sorting with pointers: 39593.385600 18.570473 percent faster ------- gdc-4.4 -frelease -O3 -march=native -ftree-vectorize ------- Sorting with Array.opIndex: 41454.052200 Sorting with pointers: 38331.517560 7.532520 percent faster Sorting with Array.opIndex: 41109.852720 Sorting with pointers: 37836.883320 7.961521 percent faster Sorting with Array.opIndex: 40587.349320 Sorting with pointers: 37390.488120 7.876497 percent faster ------- dmd-2.050 -release -O -inline ------- Sorting with Array.opIndex: 53561.598720 Sorting with pointers: 48348.626760 9.732667 percent faster Sorting with Array.opIndex: 55861.658280 Sorting with pointers: 49909.880760 10.654495 percent faster Sorting with Array.opIndex: 56887.660800 Sorting with pointers: 51470.453400 9.522640 percent faster ------- I noticed that with dmd -inline needs to be explicitly set. Otherwise there appears to be nothing to suggest a wild difference between using opIndex and pointers. :~) Regards
