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Diffstat (limited to 'vendor/github.com/tmthrgd/go-hex/hex_amd64.go')
-rw-r--r--vendor/github.com/tmthrgd/go-hex/hex_amd64.go94
1 files changed, 94 insertions, 0 deletions
diff --git a/vendor/github.com/tmthrgd/go-hex/hex_amd64.go b/vendor/github.com/tmthrgd/go-hex/hex_amd64.go
new file mode 100644
index 000000000..0f9f9a5c7
--- /dev/null
+++ b/vendor/github.com/tmthrgd/go-hex/hex_amd64.go
@@ -0,0 +1,94 @@
+// Copyright 2016 Tom Thorogood. All rights reserved.
+// Use of this source code is governed by a
+// Modified BSD License license that can be found in
+// the LICENSE file.
+
+// +build amd64,!gccgo,!appengine
+
+package hex
+
+import "golang.org/x/sys/cpu"
+
+// RawEncode encodes src into EncodedLen(len(src))
+// bytes of dst. As a convenience, it returns the number
+// of bytes written to dst, but this value is always EncodedLen(len(src)).
+// RawEncode implements hexadecimal encoding for a given alphabet.
+func RawEncode(dst, src, alpha []byte) int {
+ if len(alpha) != 16 {
+ panic("invalid alphabet")
+ }
+
+ if len(dst) < len(src)*2 {
+ panic("dst buffer is too small")
+ }
+
+ if len(src) == 0 {
+ return 0
+ }
+
+ switch {
+ case cpu.X86.HasAVX:
+ encodeAVX(&dst[0], &src[0], uint64(len(src)), &alpha[0])
+ case cpu.X86.HasSSE41:
+ encodeSSE(&dst[0], &src[0], uint64(len(src)), &alpha[0])
+ default:
+ encodeGeneric(dst, src, alpha)
+ }
+
+ return len(src) * 2
+}
+
+// Decode decodes src into DecodedLen(len(src)) bytes, returning the actual
+// number of bytes written to dst.
+//
+// If Decode encounters invalid input, it returns an error describing the failure.
+func Decode(dst, src []byte) (int, error) {
+ if len(src)%2 != 0 {
+ return 0, errLength
+ }
+
+ if len(dst) < len(src)/2 {
+ panic("dst buffer is too small")
+ }
+
+ if len(src) == 0 {
+ return 0, nil
+ }
+
+ var (
+ n uint64
+ ok bool
+ )
+ switch {
+ case cpu.X86.HasAVX:
+ n, ok = decodeAVX(&dst[0], &src[0], uint64(len(src)))
+ case cpu.X86.HasSSE41:
+ n, ok = decodeSSE(&dst[0], &src[0], uint64(len(src)))
+ default:
+ n, ok = decodeGeneric(dst, src)
+ }
+
+ if !ok {
+ return 0, InvalidByteError(src[n])
+ }
+
+ return len(src) / 2, nil
+}
+
+//go:generate go run asm_gen.go
+
+// This function is implemented in hex_encode_amd64.s
+//go:noescape
+func encodeAVX(dst *byte, src *byte, len uint64, alpha *byte)
+
+// This function is implemented in hex_encode_amd64.s
+//go:noescape
+func encodeSSE(dst *byte, src *byte, len uint64, alpha *byte)
+
+// This function is implemented in hex_decode_amd64.s
+//go:noescape
+func decodeAVX(dst *byte, src *byte, len uint64) (n uint64, ok bool)
+
+// This function is implemented in hex_decode_amd64.s
+//go:noescape
+func decodeSSE(dst *byte, src *byte, len uint64) (n uint64, ok bool)