diff --git a/src/type-info.cc b/src/type-info.cc
index 78f693c..1940601 100644
--- a/src/type-info.cc
+++ b/src/type-info.cc
@@ -1,4 +1,4 @@
-// Copyright 2010 the V8 project authors. All rights reserved.
+// Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -89,7 +89,7 @@
 }
 
 
-bool TypeFeedbackOracle::StoreIsMonomorphic(Assignment* expr) {
+bool TypeFeedbackOracle::StoreIsMonomorphic(Expression* expr) {
   Handle<Object> map_or_code(GetInfo(expr->position()));
   if (map_or_code->IsMap()) return true;
   if (map_or_code->IsCode()) {
@@ -119,7 +119,7 @@
 }
 
 
-Handle<Map> TypeFeedbackOracle::StoreMonomorphicReceiverType(Assignment* expr) {
+Handle<Map> TypeFeedbackOracle::StoreMonomorphicReceiverType(Expression* expr) {
   ASSERT(StoreIsMonomorphic(expr));
   Handle<HeapObject> map_or_code(
       Handle<HeapObject>::cast(GetInfo(expr->position())));
@@ -178,7 +178,7 @@
 }
 
 ExternalArrayType TypeFeedbackOracle::GetKeyedStoreExternalArrayType(
-    Assignment* expr) {
+    Expression* expr) {
   Handle<Object> stub = GetInfo(expr->position());
   ASSERT(stub->IsCode());
   return Code::cast(*stub)->external_array_type();
@@ -244,22 +244,7 @@
   TypeInfo unknown = TypeInfo::Unknown();
   if (!object->IsCode()) return unknown;
   Handle<Code> code = Handle<Code>::cast(object);
-  if (code->is_binary_op_stub()) {
-    BinaryOpIC::TypeInfo type = static_cast<BinaryOpIC::TypeInfo>(
-        code->binary_op_type());
-    switch (type) {
-      case BinaryOpIC::UNINIT_OR_SMI:
-        return TypeInfo::Smi();
-      case BinaryOpIC::DEFAULT:
-        return (expr->op() == Token::DIV || expr->op() == Token::MUL)
-            ? TypeInfo::Double()
-            : TypeInfo::Integer32();
-      case BinaryOpIC::HEAP_NUMBERS:
-        return TypeInfo::Double();
-      default:
-        return unknown;
-    }
-  } else if (code->is_type_recording_binary_op_stub()) {
+  if (code->is_type_recording_binary_op_stub()) {
     TRBinaryOpIC::TypeInfo type = static_cast<TRBinaryOpIC::TypeInfo>(
         code->type_recording_binary_op_type());
     TRBinaryOpIC::TypeInfo result_type = static_cast<TRBinaryOpIC::TypeInfo>(
@@ -290,6 +275,8 @@
         return TypeInfo::Integer32();
       case TRBinaryOpIC::HEAP_NUMBER:
         return TypeInfo::Double();
+      case TRBinaryOpIC::BOTH_STRING:
+        return TypeInfo::String();
       case TRBinaryOpIC::STRING:
       case TRBinaryOpIC::GENERIC:
         return unknown;
@@ -355,6 +342,18 @@
 }
 
 
+void TypeFeedbackOracle::SetInfo(int position, Object* target) {
+  MaybeObject* maybe_result = dictionary_->AtNumberPut(position, target);
+  USE(maybe_result);
+#ifdef DEBUG
+  Object* result;
+  // Dictionary has been allocated with sufficient size for all elements.
+  ASSERT(maybe_result->ToObject(&result));
+  ASSERT(*dictionary_ == result);
+#endif
+}
+
+
 void TypeFeedbackOracle::PopulateMap(Handle<Code> code) {
   Isolate* isolate = Isolate::Current();
   HandleScope scope(isolate);
@@ -371,51 +370,43 @@
   int length = code_positions.length();
   ASSERT(source_positions.length() == length);
   for (int i = 0; i < length; i++) {
-    HandleScope loop_scope(isolate);
+    AssertNoAllocation no_allocation;
     RelocInfo info(code->instruction_start() + code_positions[i],
                    RelocInfo::CODE_TARGET, 0);
-    Handle<Code> target(Code::GetCodeFromTargetAddress(info.target_address()));
+    Code* target = Code::GetCodeFromTargetAddress(info.target_address());
     int position = source_positions[i];
     InlineCacheState state = target->ic_state();
     Code::Kind kind = target->kind();
-    Handle<Object> value;
-    if (kind == Code::BINARY_OP_IC ||
-        kind == Code::TYPE_RECORDING_BINARY_OP_IC ||
+
+    if (kind == Code::TYPE_RECORDING_BINARY_OP_IC ||
         kind == Code::COMPARE_IC) {
       // TODO(kasperl): Avoid having multiple ICs with the same
       // position by making sure that we have position information
       // recorded for all binary ICs.
       int entry = dictionary_->FindEntry(position);
       if (entry == NumberDictionary::kNotFound) {
-        value = target;
+        SetInfo(position, target);
       }
     } else if (state == MONOMORPHIC) {
       if (kind == Code::KEYED_EXTERNAL_ARRAY_LOAD_IC ||
           kind == Code::KEYED_EXTERNAL_ARRAY_STORE_IC) {
-        value = target;
+        SetInfo(position, target);
       } else if (target->kind() != Code::CALL_IC ||
           target->check_type() == RECEIVER_MAP_CHECK) {
         Map* map = target->FindFirstMap();
         if (map == NULL) {
-          value = target;
+          SetInfo(position, target);
         } else {
-          value = Handle<Map>(map);
+          SetInfo(position, map);
         }
       } else {
         ASSERT(target->kind() == Code::CALL_IC);
         CheckType check = target->check_type();
         ASSERT(check != RECEIVER_MAP_CHECK);
-        value = Handle<Object>(Smi::FromInt(check));
+        SetInfo(position, Smi::FromInt(check));
       }
     } else if (state == MEGAMORPHIC) {
-      value = target;
-    }
-
-    if (!value.is_null()) {
-      Handle<NumberDictionary> new_dict =
-          isolate->factory()->DictionaryAtNumberPut(
-              dictionary_, position, value);
-      dictionary_ = loop_scope.CloseAndEscape(new_dict);
+      SetInfo(position, target);
     }
   }
   // Allocate handle in the parent scope.
@@ -441,9 +432,7 @@
       if (target->is_inline_cache_stub()) {
         InlineCacheState state = target->ic_state();
         Code::Kind kind = target->kind();
-        if (kind == Code::BINARY_OP_IC) {
-          if (target->binary_op_type() == BinaryOpIC::GENERIC) continue;
-        } else if (kind == Code::TYPE_RECORDING_BINARY_OP_IC) {
+        if (kind == Code::TYPE_RECORDING_BINARY_OP_IC) {
           if (target->type_recording_binary_op_type() ==
               TRBinaryOpIC::GENERIC) {
             continue;