Robin Gareus
8f333acb80
marginal improvement on x86_64 for zero, 5-10% for tiny numbers;
100% time improvement (half the time) on i686 with zero.
#/bin/sh
g++ -x c++ -O3 -ffast-math -o /tmp/a.out - << EOF
#include <stdio.h>
#include <stdlib.h>
#include <cmath>
#include <limits>
static inline float accurate_coefficient_to_dB (float coeff) {
#if 1 // try me
if (coeff < 1e-15) return -std::numeric_limits<float>::infinity();
#endif
return 20.0f * log10f (coeff);
}
int main (int argc, char **argv) {
long long int i;
float f = 0;
if (argc < 3) return -1;
long long int end = atoll (argv[1]);
for (i = 0; i < end; ++i) {
f += accurate_coefficient_to_dB (atof (argv[2]));
}
printf ("%f\n",f);
return 0;
}
EOF
time /tmp/a.out 100000000000 0.0
time /tmp/a.out 100000000000 0.0
time /tmp/a.out 100000000000 0.0
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|---|---|---|
| cfgtool | ||
| doc | ||
| export | ||
| gtk2_ardour | ||
| headless | ||
| icons | ||
| libs | ||
| mcp | ||
| midi_maps | ||
| msvc_extra_headers | ||
| MSVCardour3 | ||
| MSVCMixbus3 | ||
| MSVCvst_scan | ||
| patches | ||
| patchfiles | ||
| templates | ||
| tools | ||
| vst | ||
| .dir-locals.el | ||
| .gitignore | ||
| ardour-3.ttl | ||
| ardour.1 | ||
| ardour.1.es | ||
| ardour.1.fr | ||
| ardour.1.ru | ||
| ardour.dox | ||
| COPYING | ||
| instant.xml | ||
| instant.xml.sae | ||
| Makefile | ||
| msvc32-fixup.pl | ||
| PACKAGER_README | ||
| README | ||
| system_config | ||
| testfile.flac | ||
| testfile.ogg | ||
| TRANSLATORS | ||
| waf | ||
| wscript | ||
Please see the Ardour web site at http://ardour.org/ for all documentation..
For information on building ardour:
http://ardour.org/development.html