https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77689

--- Comment #7 from UroŇ° Bizjak <ubizjak at gmail dot com> ---
(In reply to morandidodo from comment #6)

> However, I just made some tests, and it seems that the performance lost is
> particularly related to std::log. If something else is being used, like
> std::sqrt for example, the code compiled with gcc is still slower, but less.

Adding -mveclibabi=svml should vectorize calls to these functions, but you'd
have to link with SVML vector library then.

icc is doing this by default:

  400e0f:       e8 ac 16 00 00          callq  4024c0 <__svml_log4>

but gcc doesn't:

  40078b:       e8 00 ff ff ff          callq  400690 <log@plt>

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