fix the compare nil ic

src/code-stubs.cc

Index: src/code-stubs.cc
diff --git a/src/code-stubs.cc b/src/code-stubs.cc
index 312febc1aa5701d0de3d3a10534d809f0db74647..59d56375da1305e73c420dd4a78b59fca0887ae2 100644
--- a/src/code-stubs.cc
+++ b/src/code-stubs.cc
@@ -45,7 +45,8 @@ CodeStubInterfaceDescriptor::CodeStubInterfaceDescriptor()
       function_mode_(NOT_JS_FUNCTION_STUB_MODE),
       register_params_(NULL),
       deoptimization_handler_(NULL),
-      miss_handler_(IC_Utility(IC::kUnreachable), Isolate::Current()) { }
+      miss_handler_(IC_Utility(IC::kUnreachable), Isolate::Current()),
+      has_miss_handler_(false) { }
 
 
 bool CodeStub::FindCodeInCache(Code** code_out, Isolate* isolate) {
@@ -410,6 +411,7 @@ void ICCompareStub::Generate(MacroAssembler* masm) {
 
 void CompareNilICStub::Record(Handle<Object> object) {
   ASSERT(types_ != Types::FullCompare());
+  Types old_types(types_);
   if (equality_kind_ == kStrictEquality) {
     // When testing for strict equality only one value will evaluate to true
     types_.RemoveAll();
@@ -430,6 +432,22 @@ void CompareNilICStub::Record(Handle<Object> object) {
       types_.Add(MONOMORPHIC_MAP);
     }
   }
+  old_types.TraceTransition(types_);
+}
+
+
+void CompareNilICStub::Types::TraceTransition(Types to) const {
+  if (!FLAG_trace_ic) return;
+  char buffer[100];
+  NoAllocationStringAllocator allocator(buffer,
+                                        static_cast<unsigned>(sizeof(buffer)));
+  StringStream stream(&allocator);
+  stream.Add("[CompareNilIC (");
+  Print(&stream);
+  stream.Add("->");
+  to.Print(&stream);
+  stream.Add(")]\n");
+  stream.OutputToStdOut();
 }