optimized switch implementation

src/wasm/switch-logic.h

Index: src/wasm/switch-logic.h
diff --git a/src/wasm/switch-logic.h b/src/wasm/switch-logic.h
new file mode 100644
index 0000000000000000000000000000000000000000..03da45a6ba56ff0f8e9159d9942ab25fbf3b4b18
--- /dev/null
+++ b/src/wasm/switch-logic.h
@@ -0,0 +1,32 @@
+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef V8_WASM_SWITCH_LOGIC_H
+#define V8_WASM_SWITCH_LOGIC_H
+
+#include "src/zone-containers.h"
+#include "src/zone.h"
+
+namespace v8 {
+namespace internal {
+namespace wasm {
+
+class CaseNode : public ZoneObject {
+ public:
+  int begin_;

[bradn, 2016/03/31 21:39:09]

Since you're using this as a struct, the style guide calls for it to be declared
that way, and the _ is for private member variables.

Or I suppose you could keep it a class with accessors, as begin + end are
immutable one created?

[aseemgarg, 2016/03/31 22:04:54]

Done.

+  int end_;
+  CaseNode* left_;
+  CaseNode* right_;
+  CaseNode(int begin, int end) : begin_(begin), end_(end) {
+    left_ = nullptr;
+    right_ = nullptr;
+  }
+};
+
+CaseNode* OrderCases(ZoneVector<int>* cases, Zone* zone);
+}  // namespace wasm
+}  // namespace internal
+}  // namespace v8
+
+#endif