[Bug middle-end/71741] The program works 3 times slower compiled with g++ 5.3.1 than the same program compiled with g++ 4.8.4 with the same command (i7-5820 Haswell)
pinskia at gcc dot gnu.org
gcc-bugzilla@gcc.gnu.org
Sun Jul 24 07:22:00 GMT 2016
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71741
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |WAITING
Last reconfirmed| |2016-07-24
Ever confirmed|0 |1
--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Have you tried the binary you created with GCC 4.8.x and used it on the newer
distro? If it is slower there, then this is a glibc issue. It has been known
that glibc has slowed down sin/cos to make it more accurate in some corner
cases which might be what you are seeing.
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