qbit/go
1
0
Fork 0
mirror of https://github.com/golang/go synced 2024-11-20 06:54:42 -07:00
Code Releases Activity

crypto/sha1: speed up sha1 for very small blocks

Browse Source 
For very small blocks significant time is spent in checkSum function,
adding necessary padding. Instead of writing it byte by byte, copy
encoding/binary PutUint functions, which are compiled into single mov.

name            old time/op    new time/op    delta
Hash8Bytes-6       344ns ± 0%     310ns ± 0%   -9.78%  (p=0.000 n=10+9)
Hash320Bytes-6    1.28µs ± 0%    1.25µs ± 0%   -2.58%  (p=0.000 n=10+10)
Hash1K-6          2.51µs ± 0%    2.47µs ± 0%   -1.67%  (p=0.000 n=10+10)
Hash8K-6          15.8µs ± 0%    15.7µs ± 1%   -0.21%  (p=0.023 n=10+10)

name            old speed      new speed      delta
Hash8Bytes-6    23.2MB/s ± 0%  25.7MB/s ± 0%  +10.77%  (p=0.000 n=10+9)
Hash320Bytes-6   249MB/s ± 0%   256MB/s ± 0%   +2.65%  (p=0.000 n=10+10)
Hash1K-6         408MB/s ± 0%   414MB/s ± 0%   +1.70%  (p=0.000 n=10+10)

Change-Id: I3975ee929465c7dd137d0ca757ad3792a004e1a3
Reviewed-on: https://go-review.googlesource.com/54391
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Filippo Valsorda <hi@filippo.io>
This commit is contained in:
Ilya Tocar 2017-08-09 13:21:20 -05:00 committed by Filippo Valsorda
parent 27a70ea560
commit dc3b8a193c
1 changed files with 27 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

36
src/crypto/sha1/sha1.go
View File

@ -104,9 +104,7 @@ func (d *digest) checkSum() [Size]byte {
// Length in bits.
len <<= 3
for i := uint(0); i < 8; i++ {
tmp[i] = byte(len >> (56 - 8*i))
}
putUint64(tmp[:], len)
d.Write(tmp[0:8])
if d.nx != 0 {
@ -114,12 +112,12 @@ func (d *digest) checkSum() [Size]byte {
}
var digest [Size]byte
for i, s := range d.h {
digest[i*4] = byte(s >> 24)
digest[i*4+1] = byte(s >> 16)
digest[i*4+2] = byte(s >> 8)
digest[i*4+3] = byte(s)
}
putUint32(digest[0:], d.h[0])
putUint32(digest[4:], d.h[1])
putUint32(digest[8:], d.h[2])
putUint32(digest[12:], d.h[3])
putUint32(digest[16:], d.h[4])
return digest
}
@ -199,3 +197,23 @@ func Sum(data []byte) [Size]byte {
d.Write(data)
return d.checkSum()
}
func putUint64(x []byte, s uint64) {
_ = x[7]
x[0] = byte(s >> 56)
x[1] = byte(s >> 48)
x[2] = byte(s >> 40)
x[3] = byte(s >> 32)
x[4] = byte(s >> 24)
x[5] = byte(s >> 16)
x[6] = byte(s >> 8)
x[7] = byte(s)
}
func putUint32(x []byte, s uint32) {
_ = x[3]
x[0] = byte(s >> 24)
x[1] = byte(s >> 16)
x[2] = byte(s >> 8)
x[3] = byte(s)
}