--- /dev/null
+// 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.
+
+// +build amd64,!gccgo,!appengine
+
+package blake2s
+
+var (
+ useSSE4 = supportSSE4()
+ useSSSE3 = supportSSSE3()
+ useSSE2 = true // Always available on amd64
+)
+
+//go:noescape
+func supportSSSE3() bool
+
+//go:noescape
+func supportSSE4() bool
+
+//go:noescape
+func hashBlocksSSE2(h *[8]uint32, c *[2]uint32, flag uint32, blocks []byte)
+
+//go:noescape
+func hashBlocksSSSE3(h *[8]uint32, c *[2]uint32, flag uint32, blocks []byte)
+
+//go:noescape
+func hashBlocksSSE4(h *[8]uint32, c *[2]uint32, flag uint32, blocks []byte)
+
+func hashBlocks(h *[8]uint32, c *[2]uint32, flag uint32, blocks []byte) {
+ if useSSE4 {
+ hashBlocksSSE4(h, c, flag, blocks)
+ } else if useSSSE3 {
+ hashBlocksSSSE3(h, c, flag, blocks)
+ } else if useSSE2 {
+ hashBlocksSSE2(h, c, flag, blocks)
+ } else {
+ hashBlocksGeneric(h, c, flag, blocks)
+ }
+}