X64: Convert smis to holding 32 bits of payload.

src/api.cc

 // Copyright 2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2272 matching lines @@
   i::Handle<i::JSObject> js_obj(i::JSObject::cast(*hidden_props));
   i::Handle<i::String> key_obj = Utils::OpenHandle(*key);
   return i::DeleteProperty(js_obj, key_obj)->IsTrue();
 }
 
 
 void v8::Object::SetIndexedPropertiesToPixelData(uint8_t* data, int length) {
   ON_BAILOUT("v8::SetElementsToPixelData()", return);
   ENTER_V8;
   HandleScope scope;
-  if (!ApiCheck(i::Smi::IsValid(length),
+  if (!ApiCheck(length <= i::PixelArray::kMaxLength,
                 "v8::Object::SetIndexedPropertiesToPixelData()",
                 "length exceeds max acceptable value")) {
     return;
   }
   i::Handle<i::JSObject> self = Utils::OpenHandle(this);
   if (!ApiCheck(!self->IsJSArray(),
                 "v8::Object::SetIndexedPropertiesToPixelData()",
                 "JSArray is not supported")) {
     return;
   }
@@ skipping 538 matching lines @@
 Local<Value> v8::External::Wrap(void* data) {
   STATIC_ASSERT(sizeof(data) == sizeof(i::Address));
   LOG_API("External::Wrap");
   EnsureInitialized("v8::External::Wrap()");
   ENTER_V8;
   if ((reinterpret_cast<intptr_t>(data) & kAlignedPointerMask) == 0) {
     uintptr_t data_ptr = reinterpret_cast<uintptr_t>(data);
     intptr_t data_value =
         static_cast<intptr_t>(data_ptr >> i::Internals::kAlignedPointerShift);
     STATIC_ASSERT(sizeof(data_ptr) == sizeof(data_value));
-    if (i::Smi::IsIntptrValid(data_value)) {
+    if (i::Smi::IsValid(data_value)) {
       i::Handle<i::Object> obj(i::Smi::FromIntptr(data_value));
       return Utils::ToLocal(obj);
     }
   }
   return ExternalNewImpl(data);
 }
 
 
 void* v8::External::FullUnwrap(v8::Handle<v8::Value> wrapper) {
   if (IsDeadCheck("v8::External::Unwrap()")) return 0;
@@ skipping 903 matching lines @@
 
 
 char* HandleScopeImplementer::Iterate(ObjectVisitor* v, char* storage) {
   HandleScopeImplementer* thread_local =
       reinterpret_cast<HandleScopeImplementer*>(storage);
   thread_local->IterateThis(v);
   return storage + ArchiveSpacePerThread();
 }
 
 } }  // namespace v8::internal