Use weak cells to embed maps in store handler.

src/ic/x64/handler-compiler-x64.cc

Index: src/ic/x64/handler-compiler-x64.cc
diff --git a/src/ic/x64/handler-compiler-x64.cc b/src/ic/x64/handler-compiler-x64.cc
index 32dc6015828d4f5525579ef505baf33e1a7130a2..ced2b3f54bc56b3c1cb6f01762dfb3290973750b 100644
--- a/src/ic/x64/handler-compiler-x64.cc
+++ b/src/ic/x64/handler-compiler-x64.cc
@@ -324,13 +324,25 @@ void NamedStoreHandlerCompiler::GenerateRestoreName(Label* label,
 }
 
 
-void NamedStoreHandlerCompiler::GenerateRestoreNameAndMap(
-    Handle<Name> name, Handle<Map> transition) {
+void NamedStoreHandlerCompiler::GenerateRestoreName(Handle<Name> name) {
   __ Move(this->name(), name);
-  __ Move(StoreTransitionDescriptor::MapRegister(), transition);
 }
 
 
+void NamedStoreHandlerCompiler::GenerateRestoreMap(Handle<Map> transition,
+                                                   Register scratch,
+                                                   Label* miss) {
+  Handle<WeakCell> cell = Map::WeakCellForMap(transition);
+  Register map_reg = StoreTransitionDescriptor::MapRegister();
+  DCHECK(!map_reg.is(scratch));
+  __ LoadWeakValue(map_reg, cell, miss);
+  if (transition->CanBeDeprecated()) {
+    __ movl(scratch, FieldOperand(map_reg, Map::kBitField3Offset));
+    __ andl(scratch, Immediate(Map::Deprecated::kMask));
+    __ j(not_zero, miss);
+  }
+}
+
 void NamedStoreHandlerCompiler::GenerateConstantCheck(Object* constant,
                                                       Register value_reg,
                                                       Label* miss_label) {