[Interpreter] Add support for short (16 bit) operands.

src/compiler/interpreter-assembler.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_COMPILER_INTERPRETER_ASSEMBLER_H_
 #define V8_COMPILER_INTERPRETER_ASSEMBLER_H_
 
 // Clients of this interface shouldn't depend on lots of compiler internals.
 // Do not include anything from src/compiler here!
 #include "src/allocation.h"
@@ skipping 34 matching lines @@
   // Returns the index immediate for bytecode operand |operand_index| in the
   // current bytecode.
   Node* BytecodeOperandIdx(int operand_index);
   // Returns the Imm8 immediate for bytecode operand |operand_index| in the
   // current bytecode.
   Node* BytecodeOperandImm8(int operand_index);
   // Returns the register index for bytecode operand |operand_index| in the
   // current bytecode.
   Node* BytecodeOperandReg(int operand_index);
 
+  // Returns the index immediate for the wide bytecode operand |operand_index|
+  // in the current bytecode.
+  Node* BytecodeOperandWideIdx(int operand_index);
+
   // Accumulator.
   Node* GetAccumulator();
   void SetAccumulator(Node* value);
 
   // Loads from and stores to the interpreter register file.
   Node* LoadRegister(Node* reg_index);
   Node* StoreRegister(Node* value, Node* reg_index);
 
   // Returns the location in memory of the register |reg_index| in the
   // interpreter register file.
@@ skipping 76 matching lines @@
   Node* DispatchTableRawPointer();
   // Returns a tagged pointer to the current context.
   Node* ContextTaggedPointer();
 
   // Returns the offset of register |index| relative to RegisterFilePointer().
   Node* RegisterFrameOffset(Node* index);
 
   Node* SmiShiftBitsConstant();
   Node* BytecodeOperand(int operand_index);
   Node* BytecodeOperandSignExtended(int operand_index);
+  Node* BytecodeOperandWide(int operand_index);
 
   Node* CallIC(CallInterfaceDescriptor descriptor, Node* target, Node** args);
   Node* CallJSBuiltin(int context_index, Node* receiver, Node** js_args,
                       int js_arg_count);
 
   // Returns BytecodeOffset() advanced by delta bytecodes. Note: this does not
   // update BytecodeOffset() itself.
   Node* Advance(int delta);
   Node* Advance(Node* delta);
 
@@ skipping 15 matching lines @@
   bool code_generated_;
 
   DISALLOW_COPY_AND_ASSIGN(InterpreterAssembler);
 };
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_INTERPRETER_ASSEMBLER_H_