crypto/sha1: Add AVX2 version for AMD64

name             old time/op    new time/op    delta
Hash8Bytes-48       271ns ± 8%     273ns ± 5%     ~     (p=0.313 n=19+19)
Hash320Bytes-48    1.04µs ± 7%    0.75µs ± 8%  -27.66%  (p=0.000 n=20+20)
Hash1K-48          2.72µs ± 6%    1.75µs ± 6%  -35.79%  (p=0.000 n=19+20)
Hash8K-48          19.9µs ± 7%    11.6µs ± 6%  -41.84%  (p=0.000 n=20+19)

name             old speed      new speed      delta
Hash8Bytes-48    29.5MB/s ± 8%  29.3MB/s ± 5%     ~     (p=0.314 n=19+19)
Hash320Bytes-48   307MB/s ± 7%   424MB/s ± 8%  +38.29%  (p=0.000 n=20+20)
Hash1K-48         377MB/s ± 6%   587MB/s ± 6%  +55.76%  (p=0.000 n=19+20)
Hash8K-48         413MB/s ± 7%   709MB/s ± 6%  +71.85%  (p=0.000 n=20+19)

Change-Id: I2963cf744eeb2e8191d4e4223fbf6f533a7fd405
Reviewed-on: https://go-review.googlesource.com/22607
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/crypto/sha1/sha1_test.go

@@ -19,6 +19,7 @@ type sha1Test struct {
 }
 
 var golden = []sha1Test{
+	{"76245dbf96f661bd221046197ab8b9f063f11bad", "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\n"},
 	{"da39a3ee5e6b4b0d3255bfef95601890afd80709", ""},
 	{"86f7e437faa5a7fce15d1ddcb9eaeaea377667b8", "a"},
 	{"da23614e02469a0d7c7bd1bdab5c9c474b1904dc", "ab"},
@@ -120,6 +121,10 @@ func BenchmarkHash8Bytes(b *testing.B) {
 	benchmarkSize(b, 8)
 }
 
+func BenchmarkHash320Bytes(b *testing.B) {
+	benchmarkSize(b, 320)
+}
+
 func BenchmarkHash1K(b *testing.B) {
 	benchmarkSize(b, 1024)
 }

src/crypto/sha1/sha1block_amd64.go

+// Copyright 2016 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sha1
+
+//go:noescape
+
+func blockAVX2(dig *digest, p []byte)
+
+//go:noescape
+func blockAMD64(dig *digest, p []byte)
+func checkAVX2() bool
+
+var hasAVX2 = checkAVX2()
+
+func block(dig *digest, p []byte) {
+	if hasAVX2 && len(p) >= 256 {
+		blockAVX2(dig, p)
+	} else {
+		blockAMD64(dig, p)
+	}
+}

src/crypto/sha1/sha1block_decl.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build amd64 amd64p32 arm 386 s390x
+// +build amd64p32 arm 386 s390x
 
 package sha1