Implement HChange support for Smis and use it in Load/StoreNameField

src/lithium-allocator.cc

Index: src/lithium-allocator.cc
diff --git a/src/lithium-allocator.cc b/src/lithium-allocator.cc
index 74132b3b76a6138fa530aa46f72fce9883f1585e..04113e170d50a16270ea2aa64e7e9a262da7caaa 100644
--- a/src/lithium-allocator.cc
+++ b/src/lithium-allocator.cc
@@ -1057,7 +1057,7 @@ void LAllocator::ResolvePhis(HBasicBlock* block) {
       LInstruction* branch =
           InstructionAt(cur_block->last_instruction_index());
       if (branch->HasPointerMap()) {
-        if (phi->representation().IsTagged()) {
+        if (phi->representation().IsSmiOrTagged()) {
           branch->pointer_map()->RecordPointer(phi_operand, zone());
         } else if (!phi->representation().IsDouble()) {
           branch->pointer_map()->RecordUntagged(phi_operand, zone());
@@ -1640,7 +1640,7 @@ void LAllocator::TraceAlloc(const char* msg, ...) {
 bool LAllocator::HasTaggedValue(int virtual_register) const {
   HValue* value = graph_->LookupValue(virtual_register);
   if (value == NULL) return false;
-  return value->representation().IsTagged();
+  return value->representation().IsSmiOrTagged();
 }