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

src/interpreter/bytecode-decoder.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_DECODER_H_
+#define V8_INTERPRETER_BYTECODE_DECODER_H_
+
+#include <iosfwd>
+
+#include "src/interpreter/bytecode-register.h"
+#include "src/interpreter/bytecodes.h"
+
+namespace v8 {
+namespace internal {
+namespace interpreter {
+
+class BytecodeDecoder final {
+ public:
+  // Decodes a register operand in a byte array.
+  static Register DecodeRegisterOperand(const uint8_t* operand_start,
+                                        OperandType operand_type,
+                                        OperandScale operand_scale);
+
+  // Decodes a signed operand in a byte array.
+  static int32_t DecodeSignedOperand(const uint8_t* operand_start,
+                                     OperandType operand_type,
+                                     OperandScale operand_scale);
+
+  // Decodes an unsigned operand in a byte array.
+  static uint32_t DecodeUnsignedOperand(const uint8_t* operand_start,
+                                        OperandType operand_type,
+                                        OperandScale operand_scale);
+
+  // Decode a single bytecode and operands to |os|.
+  static std::ostream& Decode(std::ostream& os, const uint8_t* bytecode_start,
+                              int number_of_parameters);
+};
+
+}  // namespace interpreter
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_INTERPRETER_BYTECODE_DECODER_H_