[Intepreter] Extend and move Register class.

src/interpreter/bytecodes.h

 // Copyright 2015 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_INTERPRETER_BYTECODES_H_
 #define V8_INTERPRETER_BYTECODES_H_
 
 #include <iosfwd>
 
 // Clients of this interface shouldn't depend on lots of interpreter internals.
@@ skipping 58 matching lines @@
   BYTECODE_LIST(DECLARE_BYTECODE)
 #undef DECLARE_BYTECODE
 #define COUNT_BYTECODE(x, ...) +1
   // The COUNT_BYTECODE macro will turn this into kLast = -1 +1 +1... which will
   // evaluate to the same value as the last real bytecode.
   kLast = -1 BYTECODE_LIST(COUNT_BYTECODE)
 #undef COUNT_BYTECODE
 };
 
 
+// An interpreter register which is located in the function's register file
+// in its stack-frame. Register hold parameters, this, and expression values.
+class Register {
+ public:
+  static const int kMaxRegisterIndex = 127;
+  static const int kMinRegisterIndex = -128;
+
+  explicit Register(int index) : index_(index) {
+    DCHECK_LE(index_, kMaxRegisterIndex);
+    DCHECK_GE(index_, kMinRegisterIndex);
+  }
+
+  int index() const { return index_; }
+  bool is_parameter() const { return index_ < 0; }
+
+  static Register FromParameterIndex(int index, int parameter_count);
+  int ToParameterIndex(int parameter_count) const;
+  static int MaxParameterIndex();
+
+  static Register FromOperand(uint8_t operand);
+  uint8_t ToOperand() const;
+
+ private:
+  void* operator new(size_t size);
+  void operator delete(void* p);
+
+  int index_;
+};
+
+
 class Bytecodes {
  public:
   // Returns string representation of |bytecode|.
   static const char* ToString(Bytecode bytecode);
 
   // Returns string representation of |operand_type|.
   static const char* OperandTypeToString(OperandType operand_type);
 
   // Returns byte value of bytecode.
   static uint8_t ToByte(Bytecode bytecode);
@@ skipping 10 matching lines @@
   // Returns the size of the bytecode including its operands.
   static int Size(Bytecode bytecode);
 
   // The maximum number of operands across all bytecodes.
   static int MaximumNumberOfOperands();
 
   // Maximum size of a bytecode and its operands.
   static int MaximumSize();
 
   // Decode a single bytecode and operands to |os|.
-  static std::ostream& Decode(std::ostream& os, const uint8_t* bytecode_start);
+  static std::ostream& Decode(std::ostream& os, const uint8_t* bytecode_start,
+                              int number_of_parameters);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(Bytecodes);
 };
 
 std::ostream& operator<<(std::ostream& os, const Bytecode& bytecode);
 std::ostream& operator<<(std::ostream& os, const OperandType& operand_type);
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_INTERPRETER_BYTECODES_H_