Stefan Krah <stefan-use...@bytereef.org> added the comment: I wonder if calling _Py_SET_53BIT_PRECISION_START/_Py_SET_53BIT_PRECISION_END every time will have any measurable effect on performance. First, string conversions have a lot of overhead already. Then, for compilers that already set the correct control word, only fnstcw is called.
Attached is a quick and dirty benchmark. The correct state is set at the start of the program. The first loop does not change the FPU state, the second one uses the macros, the third one always sets/restores. time: 0.000000 result: 1.90013e+122 time (fnstcw): 0.570000 result: 1.90013e+122 time (fnstcw/fldcw): 2.560000 result: 1.90013e+122 I would feel more comfortable if the correct FPU state is guaranteed. ---------- Added file: http://bugs.python.org/file19066/fpuspeed.c _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue9980> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
