commit 236cd056e871acb8731cd84b5bfb6f0feb646589
author Szabolcs Nagy <nsz@port70.net> Sat Dec 01 00:40:47 2018 +0000
committer Rich Felker <dalias@aerifal.cx> Wed Apr 17 23:44:59 2019 -0400
tree ecdff2e63f92275d44f4d07af01f5e31193c8d1a
parent d28cd0ad428d63c186003fdf9c02470561650a04

math: new log

from https://github.com/ARM-software/optimized-routines,
commit 04884bd04eac4b251da4026900010ea7d8850edc

Assume __FP_FAST_FMA implies __builtin_fma is inlined as a single
instruction.

code size change: +4588 bytes (+2540 bytes with fma).
benchmark on x86_64 before, after, speedup:

-Os:
   log rthruput:  12.61 ns/call  7.95 ns/call 1.59x
    log latency:  41.64 ns/call 23.38 ns/call 1.78x
-O3:
   log rthruput:  12.51 ns/call  7.75 ns/call 1.61x
    log latency:  41.82 ns/call 23.55 ns/call 1.78x