Track field types.

src/ia32/stub-cache-ia32.cc

Index: src/ia32/stub-cache-ia32.cc
diff --git a/src/ia32/stub-cache-ia32.cc b/src/ia32/stub-cache-ia32.cc
index 1a745c7b7f32a7659e5a96d208c8060b0fb5393d..209bfa6d815d2461dc776f16c9f624b8245f6a79 100644
--- a/src/ia32/stub-cache-ia32.cc
+++ b/src/ia32/stub-cache-ia32.cc
@@ -528,7 +528,13 @@ void StoreStubCompiler::GenerateStoreTransition(MacroAssembler* masm,
   } else if (representation.IsSmi()) {
       __ JumpIfNotSmi(value_reg, miss_label);
   } else if (representation.IsHeapObject()) {
-    __ JumpIfSmi(value_reg, miss_label);
+    HeapType* field_type = descriptors->GetFieldType(descriptor);
+    if (field_type->IsClass()) {
+      __ CheckMap(value_reg, field_type->AsClass(), miss_label, DO_SMI_CHECK);
+    } else {
+      ASSERT(HeapType::Any()->Is(field_type));
+      __ JumpIfSmi(value_reg, miss_label);
+    }
   } else if (representation.IsDouble()) {
     Label do_store, heap_number;
     __ AllocateHeapNumber(storage_reg, scratch1, scratch2, slow);
@@ -698,7 +704,13 @@ void StoreStubCompiler::GenerateStoreField(MacroAssembler* masm,
   if (representation.IsSmi()) {
     __ JumpIfNotSmi(value_reg, miss_label);
   } else if (representation.IsHeapObject()) {
-    __ JumpIfSmi(value_reg, miss_label);
+    HeapType* field_type = lookup->GetFieldType();
+    if (field_type->IsClass()) {
+      __ CheckMap(value_reg, field_type->AsClass(), miss_label, DO_SMI_CHECK);
+    } else {
+      ASSERT(HeapType::Any()->Is(field_type));
+      __ JumpIfSmi(value_reg, miss_label);
+    }
   } else if (representation.IsDouble()) {
     // Load the double storage.
     if (index < 0) {