[interpreter] Reduce dependencies in bytecodes.{h,cc}

src/interpreter/bytecode-register.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_BYTECODE_REGISTER_H_
+#define V8_INTERPRETER_BYTECODE_REGISTER_H_
+
+#include "src/interpreter/bytecodes.h"
+
+#include "src/frames.h"
+
+namespace v8 {
+namespace internal {
+namespace interpreter {
+
+// 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 final {
+ public:
+  explicit Register(int index = kInvalidIndex) : index_(index) {}
+
+  int index() const { return index_; }
+  bool is_parameter() const { return index() < 0; }
+  bool is_valid() const { return index_ != kInvalidIndex; }
+
+  static Register FromParameterIndex(int index, int parameter_count);
+  int ToParameterIndex(int parameter_count) const;
+
+  // Returns an invalid register.
+  static Register invalid_value() { return Register(); }
+
+  // Returns the register for the function's closure object.
+  static Register function_closure();
+  bool is_function_closure() const;
+
+  // Returns the register which holds the current context object.
+  static Register current_context();
+  bool is_current_context() const;
+
+  // Returns the register for the incoming new target value.
+  static Register new_target();
+  bool is_new_target() const;
+
+  // Returns the register for the bytecode array.
+  static Register bytecode_array();
+  bool is_bytecode_array() const;
+
+  // Returns the register for the saved bytecode offset.
+  static Register bytecode_offset();
+  bool is_bytecode_offset() const;
+
+  // Returns a register that can be used to represent the accumulator
+  // within code in the interpreter, but should never be emitted in
+  // bytecode.
+  static Register virtual_accumulator();
+
+  OperandSize SizeOfOperand() const;
+
+  int32_t ToOperand() const { return kRegisterFileStartOffset - index_; }
+  static Register FromOperand(int32_t operand) {
+    return Register(kRegisterFileStartOffset - operand);
+  }
+
+  static bool AreContiguous(Register reg1, Register reg2,
+                            Register reg3 = Register(),
+                            Register reg4 = Register(),
+                            Register reg5 = Register());
+
+  std::string ToString(int parameter_count);
+
+  bool operator==(const Register& other) const {
+    return index() == other.index();
+  }
+  bool operator!=(const Register& other) const {
+    return index() != other.index();
+  }
+  bool operator<(const Register& other) const {
+    return index() < other.index();
+  }
+  bool operator<=(const Register& other) const {
+    return index() <= other.index();
+  }
+  bool operator>(const Register& other) const {
+    return index() > other.index();
+  }
+  bool operator>=(const Register& other) const {
+    return index() >= other.index();
+  }
+
+ private:
+  static const int kInvalidIndex = kMaxInt;
+  static const int kRegisterFileStartOffset =
+      InterpreterFrameConstants::kRegisterFileFromFp / kPointerSize;
+
+  void* operator new(size_t size) = delete;
+  void operator delete(void* p) = delete;
+
+  int index_;
+};
+
+}  // namespace interpreter
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_INTERPRETER_BYTECODE_REGISTER_H_