[interpreter] Add support for scalable operands.

src/interpreter/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_INTERPRETER_INTERPRETER_ASSEMBLER_H_
 #define V8_INTERPRETER_INTERPRETER_ASSEMBLER_H_
 
 #include "src/allocation.h"
 #include "src/base/smart-pointers.h"
 #include "src/builtins.h"
 #include "src/compiler/code-stub-assembler.h"
 #include "src/frames.h"
 #include "src/interpreter/bytecodes.h"
 #include "src/runtime/runtime.h"
 
 namespace v8 {
 namespace internal {
 namespace interpreter {
 
 class InterpreterAssembler : public compiler::CodeStubAssembler {
  public:
-  InterpreterAssembler(Isolate* isolate, Zone* zone, Bytecode bytecode);
+  InterpreterAssembler(Isolate* isolate, Zone* zone, Bytecode bytecode,
+                       OperandScale operand_scale);
   virtual ~InterpreterAssembler();
 
   // Returns the count immediate for bytecode operand |operand_index| in the
   // current bytecode.
   compiler::Node* BytecodeOperandCount(int operand_index);
+  // Returns the 8-bit flag for bytecode operand |operand_index| in the
+  // current bytecode.
+  compiler::Node* BytecodeOperandFlag(int operand_index);
   // Returns the index immediate for bytecode operand |operand_index| in the
   // current bytecode.
   compiler::Node* BytecodeOperandIdx(int operand_index);
   // Returns the Imm8 immediate for bytecode operand |operand_index| in the
   // current bytecode.
   compiler::Node* BytecodeOperandImm(int operand_index);
   // Returns the register index for bytecode operand |operand_index| in the
   // current bytecode.
   compiler::Node* BytecodeOperandReg(int operand_index);
+  // Returns the runtime id immediate for bytecode operand
+  // |operand_index| in the current bytecode.
+  compiler::Node* BytecodeOperandRuntimeId(int operand_index);
 
   // Accumulator.
   compiler::Node* GetAccumulator();
   void SetAccumulator(compiler::Node* value);
 
   // Context.
   compiler::Node* GetContext();
   void SetContext(compiler::Node* value);
 
   // Loads from and stores to the interpreter register file.
@@ skipping 82 matching lines @@
   // Dispatch to the bytecode.
   void Dispatch();
 
   // Dispatch to bytecode handler.
   void DispatchToBytecodeHandler(compiler::Node* handler,
                                  compiler::Node* bytecode_offset);
   void DispatchToBytecodeHandler(compiler::Node* handler) {
     DispatchToBytecodeHandler(handler, BytecodeOffset());
   }
 
+  // Dispatch bytecode as wide operand variant.
+  void DispatchWide(OperandScale operand_scale);
+
   // Abort with the given bailout reason.
   void Abort(BailoutReason bailout_reason);
 
  protected:
   static bool TargetSupportsUnalignedAccess();
 
  private:
   // Returns a raw pointer to start of the register file on the stack.
   compiler::Node* RegisterFileRawPointer();
   // Returns a tagged pointer to the current function's BytecodeArray object.
@@ skipping 11 matching lines @@
   // Traces the current bytecode by calling |function_id|.
   void TraceBytecode(Runtime::FunctionId function_id);
 
   // Updates the bytecode array's interrupt budget by |weight| and calls
   // Runtime::kInterrupt if counter reaches zero.
   void UpdateInterruptBudget(compiler::Node* weight);
 
   // Returns the offset of register |index| relative to RegisterFilePointer().
   compiler::Node* RegisterFrameOffset(compiler::Node* index);
 
-  compiler::Node* BytecodeOperand(int operand_index);
-  compiler::Node* BytecodeOperandSignExtended(int operand_index);
-  compiler::Node* BytecodeOperandShort(int operand_index);
-  compiler::Node* BytecodeOperandShortSignExtended(int operand_index);
+  // Returns the offset of an operand relative to the current bytecode offset.
+  compiler::Node* OperandOffset(int operand_index);
+
+  // Returns a Word32 built from |count| unaligned bytes in the
+  // bytecode array starting at |relative_offset| from the current
+  // bytecode.  The |msb_type| determines if the value is signed or
+  // unsigned.

[rmcilroy, 2016/03/21 12:41:36]

Mention this should only be used on architectures which don't explicitly support
unaligned access natively.

[oth, 2016/03/21 14:21:49]

Done.

+  compiler::Node* BytecodeReadUnalignedBytes(int relative_offset, int count,
+                                             MachineType msb_type);
+
+  compiler::Node* BytecodeOperandUnsignedByte(int operand_index);
+  compiler::Node* BytecodeOperandSignedByte(int operand_index);
+  compiler::Node* BytecodeOperandUnsignedShort(int operand_index);
+  compiler::Node* BytecodeOperandSignedShort(int operand_index);
+  compiler::Node* BytecodeOperandUnsignedQuad(int operand_index);
+  compiler::Node* BytecodeOperandSignedQuad(int operand_index);
+
+  compiler::Node* BytecodeSignedOperand(int operand_index,
+                                        OperandSize operand_size);
+  compiler::Node* BytecodeUnsignedOperand(int operand_index,
+                                          OperandSize operand_size);
 
   // Returns BytecodeOffset() advanced by delta bytecodes. Note: this does not
   // update BytecodeOffset() itself.
   compiler::Node* Advance(int delta);
   compiler::Node* Advance(compiler::Node* delta);
 
   // Starts next instruction dispatch at |new_bytecode_offset|.
   void DispatchTo(compiler::Node* new_bytecode_offset);
 
   // Abort operations for debug code.
   void AbortIfWordNotEqual(compiler::Node* lhs, compiler::Node* rhs,
                            BailoutReason bailout_reason);
 
+  OperandScale operand_scale() const { return operand_scale_; }
+
   Bytecode bytecode_;
+  OperandScale operand_scale_;
   CodeStubAssembler::Variable accumulator_;
   CodeStubAssembler::Variable context_;
   CodeStubAssembler::Variable bytecode_array_;
 
   bool disable_stack_check_across_call_;
   compiler::Node* stack_pointer_before_call_;
 
   DISALLOW_COPY_AND_ASSIGN(InterpreterAssembler);
 };
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_INTERPRETER_INTERPRETER_ASSEMBLER_H_