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-rw-r--r--vendor/golang.org/x/sys/cpu/byteorder.go66
1 files changed, 66 insertions, 0 deletions
diff --git a/vendor/golang.org/x/sys/cpu/byteorder.go b/vendor/golang.org/x/sys/cpu/byteorder.go
new file mode 100644
index 0000000..271055b
--- /dev/null
+++ b/vendor/golang.org/x/sys/cpu/byteorder.go
@@ -0,0 +1,66 @@
+// Copyright 2019 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 cpu
+
+import (
+	"runtime"
+)
+
+// byteOrder is a subset of encoding/binary.ByteOrder.
+type byteOrder interface {
+	Uint32([]byte) uint32
+	Uint64([]byte) uint64
+}
+
+type littleEndian struct{}
+type bigEndian struct{}
+
+func (littleEndian) Uint32(b []byte) uint32 {
+	_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+}
+
+func (littleEndian) Uint64(b []byte) uint64 {
+	_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
+		uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+}
+
+func (bigEndian) Uint32(b []byte) uint32 {
+	_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
+}
+
+func (bigEndian) Uint64(b []byte) uint64 {
+	_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
+	return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
+		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
+}
+
+// hostByteOrder returns littleEndian on little-endian machines and
+// bigEndian on big-endian machines.
+func hostByteOrder() byteOrder {
+	switch runtime.GOARCH {
+	case "386", "amd64", "amd64p32",
+		"alpha",
+		"arm", "arm64",
+		"loong64",
+		"mipsle", "mips64le", "mips64p32le",
+		"nios2",
+		"ppc64le",
+		"riscv", "riscv64",
+		"sh":
+		return littleEndian{}
+	case "armbe", "arm64be",
+		"m68k",
+		"mips", "mips64", "mips64p32",
+		"ppc", "ppc64",
+		"s390", "s390x",
+		"shbe",
+		"sparc", "sparc64":
+		return bigEndian{}
+	}
+	panic("unknown architecture")
+}