[Bug middle-end/44053] "benchmark" function attribute.

[pinskia at gcc dot gnu dot org]

------- Comment #8 from pinskia at gcc dot gnu dot org  2010-05-10 22:49 -------
>Anyway, the result of much benchmarking shows that:

Is it?  It definitely moves from the x87 registers to the SSE registers which
can be slow.  Micro benchmarks are not always true benchmarks.  Also there are
otherways of benchmarking something like isnan.  Make a big array of random
numbers (who's seed is based on the wall clock) and then test it that way. 
Save the seed somewhere you read it into the program if you want consistent
numbers.  Add the number isnan returns non zero and that should give you a good
benchmark.  Better than what you have below.  


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44053