Checking in vendor folder for ease of using go get.

vendor/golang.org/x/sys/cpu/cpu.go

@@ -0,0 +1,38 @@
+// Copyright 2018 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 implements processor feature detection for
+// various CPU architectures.
+package cpu
+
+// CacheLinePad is used to pad structs to avoid false sharing.
+type CacheLinePad struct{ _ [cacheLineSize]byte }
+
+// X86 contains the supported CPU features of the
+// current X86/AMD64 platform. If the current platform
+// is not X86/AMD64 then all feature flags are false.
+//
+// X86 is padded to avoid false sharing. Further the HasAVX
+// and HasAVX2 are only set if the OS supports XMM and YMM
+// registers in addition to the CPUID feature bit being set.
+var X86 struct {
+	_            CacheLinePad
+	HasAES       bool // AES hardware implementation (AES NI)
+	HasADX       bool // Multi-precision add-carry instruction extensions
+	HasAVX       bool // Advanced vector extension
+	HasAVX2      bool // Advanced vector extension 2
+	HasBMI1      bool // Bit manipulation instruction set 1
+	HasBMI2      bool // Bit manipulation instruction set 2
+	HasERMS      bool // Enhanced REP for MOVSB and STOSB
+	HasFMA       bool // Fused-multiply-add instructions
+	HasOSXSAVE   bool // OS supports XSAVE/XRESTOR for saving/restoring XMM registers.
+	HasPCLMULQDQ bool // PCLMULQDQ instruction - most often used for AES-GCM
+	HasPOPCNT    bool // Hamming weight instruction POPCNT.
+	HasSSE2      bool // Streaming SIMD extension 2 (always available on amd64)
+	HasSSE3      bool // Streaming SIMD extension 3
+	HasSSSE3     bool // Supplemental streaming SIMD extension 3
+	HasSSE41     bool // Streaming SIMD extension 4 and 4.1
+	HasSSE42     bool // Streaming SIMD extension 4 and 4.2
+	_            CacheLinePad
+}