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

src/snapshot/deserializer.cc

 // Copyright 2016 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/snapshot/deserializer.h"
 
 #include "src/bootstrapper.h"
 #include "src/external-reference-table.h"
 #include "src/heap/heap.h"
 #include "src/isolate.h"
@@ skipping 81 matching lines @@
     isolate_->heap()->RepairFreeListsAfterDeserialization();
     isolate_->heap()->IterateWeakRoots(this, VISIT_ALL);
     DeserializeDeferredObjects();
     FlushICacheForNewIsolate();
   }
 
   isolate_->heap()->set_native_contexts_list(
       isolate_->heap()->undefined_value());
   // The allocation site list is build during root iteration, but if no sites
   // were encountered then it needs to be initialized to undefined.
-  if (isolate_->heap()->allocation_sites_list() == Smi::FromInt(0)) {
+  if (isolate_->heap()->allocation_sites_list() == Smi::kZero) {
     isolate_->heap()->set_allocation_sites_list(
         isolate_->heap()->undefined_value());
   }
 
   // Issue code events for newly deserialized code objects.
   LOG_CODE_EVENT(isolate_, LogCodeObjects());
   LOG_CODE_EVENT(isolate_, LogBytecodeHandlers());
   LOG_CODE_EVENT(isolate_, LogCompiledFunctions());
 }
 
@@ skipping 157 matching lines @@
     }
   }
   if (obj->IsAllocationSite()) {
     DCHECK(obj->IsAllocationSite());
     // Allocation sites are present in the snapshot, and must be linked into
     // a list at deserialization time.
     AllocationSite* site = AllocationSite::cast(obj);
     // TODO(mvstanton): consider treating the heap()->allocation_sites_list()
     // as a (weak) root. If this root is relocated correctly, this becomes
     // unnecessary.
-    if (isolate_->heap()->allocation_sites_list() == Smi::FromInt(0)) {
+    if (isolate_->heap()->allocation_sites_list() == Smi::kZero) {
       site->set_weak_next(isolate_->heap()->undefined_value());
     } else {
       site->set_weak_next(isolate_->heap()->allocation_sites_list());
     }
     isolate_->heap()->set_allocation_sites_list(site);
   } else if (obj->IsCode()) {
     // We flush all code pages after deserializing the startup snapshot. In that
     // case, we only need to remember code objects in the large object space.
     // When deserializing user code, remember each individual code object.
     if (deserializing_user_code() || space == LO_SPACE) {
@@ skipping 534 matching lines @@
 
       default:
         CHECK(false);
     }
   }
   CHECK_EQ(limit, current);
   return true;
 }
 }  // namespace internal
 }  // namespace v8