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-rw-r--r--vendor/golang.org/x/sys/cpu/byteorder.go60
1 files changed, 60 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 000000000..ed8da8dea
--- /dev/null
+++ b/vendor/golang.org/x/sys/cpu/byteorder.go
@@ -0,0 +1,60 @@
+// 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 binary.LittleEndian on little-endian machines and
+// binary.BigEndian on big-endian machines.
+func hostByteOrder() byteOrder {
+ switch runtime.GOARCH {
+ case "386", "amd64", "amd64p32",
+ "arm", "arm64",
+ "mipsle", "mips64le", "mips64p32le",
+ "ppc64le",
+ "riscv", "riscv64":
+ return littleEndian{}
+ case "armbe", "arm64be",
+ "mips", "mips64", "mips64p32",
+ "ppc", "ppc64",
+ "s390", "s390x",
+ "sparc", "sparc64":
+ return bigEndian{}
+ }
+ panic("unknown architecture")
+}