An ARM version of sha1block.go with a big improvement in throughput
(up to 2.8x).
This is a partially unrolled version which performs better for small
hashes and only sacrifices a small amount of ultimate speed to a fully
unrolled version which uses 5k of code.
Code size
Before 1636 bytes
After 1880 bytes
15% larger
Benchmarks on Samsung Exynos 5 ARMv7 Chromebook
benchmark old ns/op new ns/op delta
BenchmarkHash8Bytes 1907 1136 -40.43%
BenchmarkHash1K 20280 7547 -62.79%
BenchmarkHash8K 148469 52576 -64.59%
benchmark old MB/s new MB/s speedup
BenchmarkHash8Bytes 4.19 7.04 1.68x
BenchmarkHash1K 50.49 135.68 2.69x
BenchmarkHash8K 55.18 155.81 2.82x
LGTM=dave, agl
R=dave, bradfitz, agl, adg, nick
CC=golang-codereviews
https://golang.org/cl/
56990044