On Wednesday 10 March 2010, Alberto Mardegan wrote: > Alberto Mardegan wrote: > > Does one have any figure about how the performance of the FPU is, > > compared to integer operations? > > I added some profiling to the code, and I measured the time spent by a > function which is operating on an array of points (whose coordinates are > integers) and trasforming each of them into a geographic coordinates > (latitude and longitude, floating point) and calculating the distance > from the previous point. > > http://vcs.maemo.org/git?p=maemo-mapper;a=shortlog;h=refs/heads/gps_control > map_path_calculate_distances() is in path.c, > calculate_distance() is in utils.c, > unit2latlon() is a pointer to unit2latlon_google() in tile_source.c > > > The output (application compiled with -O0):
Using an optimized build (-O2 or -O3) may sometimes change the overall picture quite dramatically. It makes almost no sense benchmarking -O0 code, because in this case all the local variables are kept in memory and are read/written before/after each operation. It's substantially different from normal code. -- Best regards, Siarhei Siamashka _______________________________________________ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
