Add gops agent

vendor/github.com/google/gops/internal/obj/stack.go

@@ -0,0 +1,21 @@
+// Copyright 2011 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 obj
+
+// For the linkers. Must match Go definitions.
+// TODO(rsc): Share Go definitions with linkers directly.
+
+const (
+	STACKSYSTEM = 0
+	StackSystem = STACKSYSTEM
+	StackBig    = 4096
+	StackGuard  = 880*stackGuardMultiplier + StackSystem
+	StackSmall  = 128
+	StackLimit  = StackGuard - StackSystem - StackSmall
+)
+
+const (
+	StackPreempt = -1314 // 0xfff...fade
+)