[interpreter] Add support for scalable operands.

src/interpreter/bytecode-generator.cc

 // 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.
 
 #include "src/interpreter/bytecode-generator.h"
 
 #include "src/ast/scopes.h"
 #include "src/compiler.h"
 #include "src/interpreter/bytecode-register-allocator.h"
 #include "src/interpreter/control-flow-builders.h"
@@ skipping 1115 matching lines @@
   builder()->JumpIfUndefined(&subject_undefined_label);
   builder()->JumpIfNull(&subject_null_label);
   Register receiver = register_allocator()->NewRegister();
   builder()->CastAccumulatorToJSObject();
   builder()->StoreAccumulatorInRegister(receiver);
 
   register_allocator()->PrepareForConsecutiveAllocations(3);
   Register cache_type = register_allocator()->NextConsecutiveRegister();
   Register cache_array = register_allocator()->NextConsecutiveRegister();
   Register cache_length = register_allocator()->NextConsecutiveRegister();
-  // Used as kRegTriple8 and kRegPair8 in ForInPrepare and ForInNext.
+  // Used as kRegTriple and kRegPair in ForInPrepare and ForInNext.
   USE(cache_array);
   builder()->ForInPrepare(cache_type);
 
   // Set up loop counter
   Register index = register_allocator()->NewRegister();
   builder()->LoadLiteral(Smi::FromInt(0));
   builder()->StoreAccumulatorInRegister(index);
 
   // The loop
   loop_builder.LoopHeader();
@@ skipping 2008 matching lines @@
 }
 
 
 int BytecodeGenerator::feedback_index(FeedbackVectorSlot slot) const {
   return info()->feedback_vector()->GetIndex(slot);
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8