Assign unique IDs to FunctionLiterals

src/ast/ast-function-literal-id-reindexer.h

Index: src/ast/ast-function-literal-id-reindexer.h
diff --git a/src/ast/ast-function-literal-id-reindexer.h b/src/ast/ast-function-literal-id-reindexer.h
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+// 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_AST_AST_FUNCTION_LITERAL_ID_REINDEXER
+#define V8_AST_AST_FUNCTION_LITERAL_ID_REINDEXER
+
+#include "src/ast/ast-traversal-visitor.h"
+#include "src/base/macros.h"
+
+namespace v8 {
+namespace internal {
+
+// Changes the ID of all FunctionLiterals in the given Expression by adding the
+// given delta.
+class AstFunctionLiteralIdReindexer final
+    : public AstTraversalVisitor<AstFunctionLiteralIdReindexer> {
+ public:
+  AstFunctionLiteralIdReindexer(size_t stack_limit, int delta);
+  ~AstFunctionLiteralIdReindexer();
+
+  void Reindex(Expression* pattern);
+
+  // AstTraversalVisitor implementation.
+  void VisitFunctionLiteral(FunctionLiteral* lit);
+
+ private:
+  int delta_;
+
+  DISALLOW_COPY_AND_ASSIGN(AstFunctionLiteralIdReindexer);
+};
+
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_AST_AST_FUNCTION_LITERAL_ID_REINDEXER