math: new log
authorSzabolcs Nagy <nsz@port70.net>
Sat, 1 Dec 2018 00:40:47 +0000 (00:40 +0000)
committerRich Felker <dalias@aerifal.cx>
Thu, 18 Apr 2019 03:44:59 +0000 (23:44 -0400)
commit236cd056e871acb8731cd84b5bfb6f0feb646589
treeecdff2e63f92275d44f4d07af01f5e31193c8d1a
parentd28cd0ad428d63c186003fdf9c02470561650a04
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
src/math/log.c
src/math/log_data.c [new file with mode: 0644]
src/math/log_data.h [new file with mode: 0644]