[async-await] (simpler) fix for Return in try/finally in async functions

src/ast/ast.h

 // Copyright 2012 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_H_
 #define V8_AST_AST_H_
 
 #include "src/ast/ast-types.h"
 #include "src/ast/ast-value-factory.h"
 #include "src/ast/modules.h"
@@ skipping 879 matching lines @@
 
   BreakStatement(BreakableStatement* target, int pos)
       : JumpStatement(pos, kBreakStatement), target_(target) {}
 
   BreakableStatement* target_;
 };
 
 
 class ReturnStatement final : public JumpStatement {
  public:
+  enum Type { kNormal, kAsyncReturn };
   Expression* expression() const { return expression_; }
 
   void set_expression(Expression* e) { expression_ = e; }
+  Type type() const { return TypeField::decode(bit_field_); }
+  bool is_async_return() const { return type() == kAsyncReturn; }
 
  private:
   friend class AstNodeFactory;
 
-  ReturnStatement(Expression* expression, int pos)
-      : JumpStatement(pos, kReturnStatement), expression_(expression) {}
+  ReturnStatement(Expression* expression, Type type, int pos)
+      : JumpStatement(pos, kReturnStatement), expression_(expression) {
+    bit_field_ |= TypeField::encode(type);
+  }
 
   Expression* expression_;
+
+  class TypeField
+      : public BitField<Type, JumpStatement::kNextBitFieldIndex, 2> {};
 };
 
 
 class WithStatement final : public Statement {
  public:
   Scope* scope() { return scope_; }
   Expression* expression() const { return expression_; }
   void set_expression(Expression* e) { expression_ = e; }
   Statement* statement() const { return statement_; }
   void set_statement(Statement* s) { statement_ = s; }
@@ skipping 2282 matching lines @@
 
   ContinueStatement* NewContinueStatement(IterationStatement* target, int pos) {
     return new (zone_) ContinueStatement(target, pos);
   }
 
   BreakStatement* NewBreakStatement(BreakableStatement* target, int pos) {
     return new (zone_) BreakStatement(target, pos);
   }
 
   ReturnStatement* NewReturnStatement(Expression* expression, int pos) {
-    return new (zone_) ReturnStatement(expression, pos);
+    return new (zone_)
+        ReturnStatement(expression, ReturnStatement::kNormal, pos);
+  }
+
+  ReturnStatement* NewAsyncReturnStatement(Expression* expression, int pos) {
+    return new (zone_)
+        ReturnStatement(expression, ReturnStatement::kAsyncReturn, pos);
   }
 
   WithStatement* NewWithStatement(Scope* scope,
                                   Expression* expression,
                                   Statement* statement,
                                   int pos) {
     return new (zone_) WithStatement(scope, expression, statement, pos);
   }
 
   IfStatement* NewIfStatement(Expression* condition,
@@ skipping 405 matching lines @@
                                     : NULL;                                   \
   }
 AST_NODE_LIST(DECLARE_NODE_FUNCTIONS)
 #undef DECLARE_NODE_FUNCTIONS
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_AST_AST_H_