Improve moves of Smi and null objects. Add result cid to List constructor calls. Add tracing of inl…

runtime/vm/assembler_x64.cc

Index: runtime/vm/assembler_x64.cc
===================================================================
--- runtime/vm/assembler_x64.cc	(revision 12183)
+++ runtime/vm/assembler_x64.cc	(working copy)
@@ -1527,7 +1527,7 @@
 
 
 void Assembler::LoadObject(Register dst, const Object& object) {
-  if (object.IsSmi()) {
+  if (object.IsSmi() || object.IsNull()) {
     movq(dst, Immediate(reinterpret_cast<int64_t>(object.raw())));
   } else {
     ASSERT(object.IsZoneHandle());
@@ -1540,7 +1540,7 @@
 
 
 void Assembler::StoreObject(const Address& dst, const Object& object) {
-  if (object.IsSmi()) {
+  if (object.IsSmi() || object.IsNull()) {
     movq(dst, Immediate(reinterpret_cast<int64_t>(object.raw())));
   } else {
     LoadObject(TMP, object);
@@ -1550,7 +1550,7 @@
 
 
 void Assembler::PushObject(const Object& object) {
-  if (object.IsSmi()) {
+  if (object.IsSmi() || object.IsNull()) {
     pushq(Immediate(reinterpret_cast<int64_t>(object.raw())));
   } else {
     LoadObject(TMP, object);
@@ -1560,7 +1560,7 @@
 
 
 void Assembler::CompareObject(Register reg, const Object& object) {
-  if (object.IsSmi()) {
+  if (object.IsSmi() || object.IsNull()) {
     cmpq(reg, Immediate(reinterpret_cast<int64_t>(object.raw())));
   } else {
     ASSERT(reg != TMP);