MIPS: Track storage types of instance variables.

src/mips/lithium-mips.cc

Index: src/mips/lithium-mips.cc
diff --git a/src/mips/lithium-mips.cc b/src/mips/lithium-mips.cc
index c2f89867d77577a7a7b59d19209d03466647d9a5..753c663bb79f0625ca217270832fc6aa1c267362 100644
--- a/src/mips/lithium-mips.cc
+++ b/src/mips/lithium-mips.cc
@@ -1988,8 +1988,8 @@ LInstruction* LChunkBuilder::DoStoreContextSlot(HStoreContextSlot* instr) {
 
 
 LInstruction* LChunkBuilder::DoLoadNamedField(HLoadNamedField* instr) {
-  return DefineAsRegister(
-      new(zone()) LLoadNamedField(UseRegisterAtStart(instr->object())));
+  LOperand* obj = UseRegisterAtStart(instr->object());
+  return DefineAsRegister(new(zone()) LLoadNamedField(obj));
 }
 
 
@@ -2194,14 +2194,20 @@ LInstruction* LChunkBuilder::DoStoreNamedField(HStoreNamedField* instr) {
         : UseRegisterAtStart(instr->object());
   }
 
-  LOperand* val = needs_write_barrier
-      ? UseTempRegister(instr->value())
-      : UseRegister(instr->value());
+  LOperand* val =
+      needs_write_barrier ||
+      (FLAG_track_fields && instr->field_representation().IsSmi())
+          ? UseTempRegister(instr->value()) : UseRegister(instr->value());
 
   // We need a temporary register for write barrier of the map field.
   LOperand* temp = needs_write_barrier_for_map ? TempRegister() : NULL;
 
-  return new(zone()) LStoreNamedField(obj, val, temp);
+  LStoreNamedField* result = new(zone()) LStoreNamedField(obj, val, temp);
+  if ((FLAG_track_fields && instr->field_representation().IsSmi()) ||
+      (FLAG_track_double_fields && instr->field_representation().IsDouble())) {
+    return AssignEnvironment(result);
+  }
+  return result;
 }