diff --git a/build/Android.gtest.mk b/build/Android.gtest.mk
index e069d88..4d1e18d 100644
--- a/build/Android.gtest.mk
+++ b/build/Android.gtest.mk
@@ -60,7 +60,9 @@
 
 ifeq ($(ART_SEA_IR_MODE),true)
 TEST_COMMON_SRC_FILES += \
-	compiler/utils/scoped_hashtable_test.cc
+	compiler/utils/scoped_hashtable_test.cc \
+	compiler/sea_ir/types/type_data_test.cc \
+	compiler/sea_ir/types/type_inference_visitor_test.cc
 endif
 
 TEST_TARGET_SRC_FILES := \
diff --git a/compiler/sea_ir/types/type_data_test.cc b/compiler/sea_ir/types/type_data_test.cc
new file mode 100644
index 0000000..a66ebce
--- /dev/null
+++ b/compiler/sea_ir/types/type_data_test.cc
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "common_test.h"
+#include "sea_ir/types/types.h"
+
+namespace sea_ir {
+
+class TypeDataTest : public art::CommonTest {
+};
+
+TEST_F(TypeDataTest, Basics) {
+  TypeData td;
+  art::verifier::RegTypeCache type_cache(false);
+  int first_instruction_id = 1;
+  int second_instruction_id = 3;
+  EXPECT_TRUE(NULL == td.FindTypeOf(first_instruction_id));
+  const Type* int_type = &type_cache.Integer();
+  const Type* byte_type = &type_cache.Byte();
+  td.SetTypeOf(first_instruction_id, int_type);
+  EXPECT_TRUE(int_type == td.FindTypeOf(first_instruction_id));
+  EXPECT_TRUE(NULL == td.FindTypeOf(second_instruction_id));
+  td.SetTypeOf(second_instruction_id, byte_type);
+  EXPECT_TRUE(int_type == td.FindTypeOf(first_instruction_id));
+  EXPECT_TRUE(byte_type == td.FindTypeOf(second_instruction_id));
+}
+
+}  // namespace art
diff --git a/compiler/sea_ir/types/type_inference_visitor.cc b/compiler/sea_ir/types/type_inference_visitor.cc
index 30537bd..3da2fc1 100644
--- a/compiler/sea_ir/types/type_inference_visitor.cc
+++ b/compiler/sea_ir/types/type_inference_visitor.cc
@@ -62,7 +62,8 @@
   crt_type_.push_back(result_type);
 }
 
-std::vector<const Type*> TypeInferenceVisitor::GetOperandTypes(InstructionNode* instruction) {
+std::vector<const Type*> TypeInferenceVisitor::GetOperandTypes(
+    InstructionNode* instruction) const {
   std::vector<InstructionNode*> sources = instruction->GetSSAProducers();
   std::vector<const Type*> types_to_merge;
   for (std::vector<InstructionNode*>::const_iterator cit = sources.begin(); cit != sources.end();
diff --git a/compiler/sea_ir/types/type_inference_visitor.h b/compiler/sea_ir/types/type_inference_visitor.h
index be1ad43..200b9f0 100644
--- a/compiler/sea_ir/types/type_inference_visitor.h
+++ b/compiler/sea_ir/types/type_inference_visitor.h
@@ -58,7 +58,7 @@
 
   const Type* MergeTypes(std::vector<const Type*>& types) const;
   const Type* MergeTypes(const Type* t1, const Type* t2) const;
-
+  std::vector<const Type*> GetOperandTypes(InstructionNode* instruction) const;
   const Type* GetType() {
     // TODO: Currently multiple defined types are not supported.
     if (crt_type_.size()>0) {
@@ -74,9 +74,6 @@
   TypeData* type_data_;
   art::verifier::RegTypeCache* type_cache_;
   std::vector<const Type*> crt_type_;             // Stored temporarily between two calls to Visit.
-
- private:
-  std::vector<const Type*> GetOperandTypes(InstructionNode* instruction);
 };
 
 }  // namespace sea_ir
diff --git a/compiler/sea_ir/types/type_inference_visitor_test.cc b/compiler/sea_ir/types/type_inference_visitor_test.cc
new file mode 100644
index 0000000..8a249eb
--- /dev/null
+++ b/compiler/sea_ir/types/type_inference_visitor_test.cc
@@ -0,0 +1,133 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "common_test.h"
+#include "sea_ir/types/type_inference_visitor.h"
+#include "sea_ir/ir/sea.h"
+
+namespace sea_ir {
+
+class TestInstructionNode:public InstructionNode {
+ public:
+  explicit TestInstructionNode(std::vector<InstructionNode*> prods): InstructionNode(NULL),
+      producers_(prods) { }
+  std::vector<InstructionNode*> GetSSAProducers() {
+    return producers_;
+  }
+ protected:
+  std::vector<InstructionNode*> producers_;
+};
+
+class TypeInferenceVisitorTest : public art::CommonTest {
+};
+
+TEST_F(TypeInferenceVisitorTest, MergeIntWithByte) {
+  TypeData td;
+  art::verifier::RegTypeCache type_cache(false);
+  TypeInferenceVisitor tiv(NULL, &td, &type_cache);
+  const Type* int_type = &type_cache.Integer();
+  const Type* byte_type = &type_cache.Byte();
+  const Type* ib_type = tiv.MergeTypes(int_type, byte_type);
+  const Type* bi_type = tiv.MergeTypes(byte_type, int_type);
+  EXPECT_TRUE(ib_type == int_type);
+  EXPECT_TRUE(bi_type == int_type);
+}
+
+TEST_F(TypeInferenceVisitorTest, MergeIntWithShort) {
+  TypeData td;
+  art::verifier::RegTypeCache type_cache(false);
+  TypeInferenceVisitor tiv(NULL, &td, &type_cache);
+  const Type* int_type = &type_cache.Integer();
+  const Type* short_type = &type_cache.Short();
+  const Type* is_type = tiv.MergeTypes(int_type, short_type);
+  const Type* si_type = tiv.MergeTypes(short_type, int_type);
+  EXPECT_TRUE(is_type == int_type);
+  EXPECT_TRUE(si_type == int_type);
+}
+
+TEST_F(TypeInferenceVisitorTest, MergeMultipleInts) {
+  int N = 10;  // Number of types to merge.
+  TypeData td;
+  art::verifier::RegTypeCache type_cache(false);
+  TypeInferenceVisitor tiv(NULL, &td, &type_cache);
+  std::vector<const Type*> types;
+  for (int i = 0; i < N; i++) {
+    const Type* new_type = &type_cache.Integer();
+    types.push_back(new_type);
+  }
+  const Type* merged_type = tiv.MergeTypes(types);
+  EXPECT_TRUE(merged_type == &type_cache.Integer());
+}
+
+TEST_F(TypeInferenceVisitorTest, MergeMultipleShorts) {
+  int N = 10;  // Number of types to merge.
+  TypeData td;
+  art::verifier::RegTypeCache type_cache(false);
+  TypeInferenceVisitor tiv(NULL, &td, &type_cache);
+  std::vector<const Type*> types;
+  for (int i = 0; i < N; i++) {
+    const Type* new_type = &type_cache.Short();
+    types.push_back(new_type);
+  }
+  const Type* merged_type = tiv.MergeTypes(types);
+  EXPECT_TRUE(merged_type == &type_cache.Short());
+}
+
+TEST_F(TypeInferenceVisitorTest, MergeMultipleIntsWithShorts) {
+  int N = 10;  // Number of types to merge.
+  TypeData td;
+  art::verifier::RegTypeCache type_cache(false);
+  TypeInferenceVisitor tiv(NULL, &td, &type_cache);
+  std::vector<const Type*> types;
+  for (int i = 0; i < N; i++) {
+    const Type* short_type = &type_cache.Short();
+    const Type* int_type = &type_cache.Integer();
+    types.push_back(short_type);
+    types.push_back(int_type);
+  }
+  const Type* merged_type = tiv.MergeTypes(types);
+  EXPECT_TRUE(merged_type == &type_cache.Integer());
+}
+
+TEST_F(TypeInferenceVisitorTest, GetOperandTypes) {
+  int N = 10;  // Number of types to merge.
+  TypeData td;
+  art::verifier::RegTypeCache type_cache(false);
+  TypeInferenceVisitor tiv(NULL, &td, &type_cache);
+  std::vector<const Type*> types;
+  std::vector<InstructionNode*> preds;
+  for (int i = 0; i < N; i++) {
+    const Type* short_type = &type_cache.Short();
+    const Type* int_type = &type_cache.Integer();
+    TestInstructionNode* short_inst =
+        new TestInstructionNode(std::vector<InstructionNode*>());
+    TestInstructionNode* int_inst =
+        new TestInstructionNode(std::vector<InstructionNode*>());
+    preds.push_back(short_inst);
+    preds.push_back(int_inst);
+    td.SetTypeOf(short_inst->Id(), short_type);
+    td.SetTypeOf(int_inst->Id(), int_type);
+    types.push_back(short_type);
+    types.push_back(int_type);
+  }
+  TestInstructionNode* inst_to_test = new TestInstructionNode(preds);
+  std::vector<const Type*> result = tiv.GetOperandTypes(inst_to_test);
+  EXPECT_TRUE(result.size() == types.size());
+  EXPECT_TRUE(true == std::equal(types.begin(), types.begin() + 2, result.begin()));
+}
+
+
+}  // namespace art
diff --git a/compiler/utils/scoped_hashtable_test.cc b/compiler/utils/scoped_hashtable_test.cc
index d5f9f7d..68608f0 100644
--- a/compiler/utils/scoped_hashtable_test.cc
+++ b/compiler/utils/scoped_hashtable_test.cc
@@ -15,7 +15,7 @@
  */
 
 #include "common_test.h"
-#include "scoped_hashtable.h"
+#include "utils/scoped_hashtable.h"
 
 using utils::ScopedHashtable;