Add Smi::Zero and replace all Smi::FromInt(0) calls

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/compile-time-value.h"
 #include "src/ast/scopes.h"
 #include "src/code-stubs.h"
 #include "src/compilation-info.h"
@@ skipping 1188 matching lines @@
   Register receiver = register_allocator()->NewRegister();
   builder()->ConvertAccumulatorToObject(receiver);
 
   // Used as kRegTriple and kRegPair in ForInPrepare and ForInNext.
   RegisterList triple = register_allocator()->NewRegisterList(3);
   Register cache_length = triple[2];
   builder()->ForInPrepare(receiver, triple);
 
   // Set up loop counter
   Register index = register_allocator()->NewRegister();
-  builder()->LoadLiteral(Smi::FromInt(0));
+  builder()->LoadLiteral(Smi::kZero);
   builder()->StoreAccumulatorInRegister(index);
 
   // The loop
   VisitIterationHeader(stmt, &loop_builder);
   builder()->SetExpressionAsStatementPosition(stmt->each());
   builder()->ForInContinue(index, cache_length);
   loop_builder.BreakIfFalse();
   FeedbackVectorSlot slot = stmt->ForInFeedbackSlot();
   builder()->ForInNext(receiver, index, triple.Truncate(2),
                        feedback_index(slot));
@@ skipping 1945 matching lines @@
 }
 
 Runtime::FunctionId BytecodeGenerator::StoreKeyedToSuperRuntimeId() {
   return is_strict(language_mode()) ? Runtime::kStoreKeyedToSuper_Strict
                                     : Runtime::kStoreKeyedToSuper_Sloppy;
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8