diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3921fa12835e3..80d1e5638b54b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -17,4 +17,5 @@ include(cmake/external/gtest.cmake)
 include(cmake/external/protobuf.cmake)
 include(cmake/external/mklml.cmake)
 
+find_package(Threads REQUIRED)
 add_subdirectory(cinn)
diff --git a/cinn/CMakeLists.txt b/cinn/CMakeLists.txt
index 0123b99c73744..e90962fce60f9 100644
--- a/cinn/CMakeLists.txt
+++ b/cinn/CMakeLists.txt
@@ -1,5 +1,6 @@
 cc_library(cinn_gtest_main SRCS gtest_main.cc DEPS gtest)
 
+add_subdirectory(utils)
 add_subdirectory(ir)
 add_subdirectory(dsl)
 add_subdirectory(optim)
diff --git a/cinn/ir/CMakeLists.txt b/cinn/ir/CMakeLists.txt
index 7ea43510c17e2..ec7fdec2c99d3 100644
--- a/cinn/ir/CMakeLists.txt
+++ b/cinn/ir/CMakeLists.txt
@@ -1,4 +1,6 @@
 cc_library(ir SRCS
-        type.cc node.cc ir.cc
+        type.cc node.cc ir.cc node.cc
         ir_visitor.cc
         )
+
+cc_test(test_ir SRCS ir_test.cc DEPS ir)
diff --git a/cinn/ir/ir.h b/cinn/ir/ir.h
index cac0b6ca045ce..5b218d2cf7eea 100644
--- a/cinn/ir/ir.h
+++ b/cinn/ir/ir.h
@@ -200,7 +200,7 @@ struct Block : public ExprNode<Block> {
 struct Builder {
   template <typename IRType, typename... Args>
   Expr make(Args... args) {
-    return std::shared_ptr<IRType>(args...);
+    return Expr(std::make_shared<IRType>(args...));
   }
 };
 
diff --git a/cinn/ir/ir_test.cc b/cinn/ir/ir_test.cc
new file mode 100644
index 0000000000000..b98f614c6e72d
--- /dev/null
+++ b/cinn/ir/ir_test.cc
@@ -0,0 +1,22 @@
+#include "cinn/ir/ir.h"
+#include <gtest/gtest.h>
+
+#include "cinn/utils/string.h"
+
+namespace cinn {
+namespace ir {
+
+TEST(ir, Add) {
+  Builder builder;
+
+  auto one = builder.make<IntImm>(Int(32), 1);
+  auto two = builder.make<IntImm>(Int(32), 2);
+
+  auto add = builder.make<Add>(one, two);
+
+  auto cnt = utils::GetStreamCnt(add.node_type());
+  ASSERT_EQ(cnt, "<node: Add>");
+}
+
+}  // namespace ir
+}  // namespace cinn
diff --git a/cinn/ir/node.cc b/cinn/ir/node.cc
index 665c9e3d79510..adee28a05eb6d 100644
--- a/cinn/ir/node.cc
+++ b/cinn/ir/node.cc
@@ -1,10 +1,34 @@
 #include "cinn/ir/node.h"
+#include "cinn/ir/ir.h"
 
 namespace cinn {
 namespace ir {
 
-template <>
-void ExprNode<IntImm>::Accept(cinn::ir::IRVisitor *v) const {}
+//! Implementations for Ir nodes.
+// @{
+#define __m(t__) \
+  template <>    \
+  void ExprNode<t__>::Accept(cinn::ir::IRVisitor *v) const {}
+NODETY_FORALL(__m)
+#undef __m
+// @}
+
+std::ostream &operator<<(std::ostream &os, IrNodeTy type) {
+  switch (type) {
+#define __m(t__)                    \
+  case IrNodeTy::t__:               \
+    os << "<node: " << #t__ << ">"; \
+    break;
+
+    NODETY_FORALL(__m)
+#undef __m
+
+    default:
+      LOG(FATAL) << "unknown IrNodeTy found";
+  }
+
+  return os;
+}
 
 }  // namespace ir
 }  // namespace cinn
diff --git a/cinn/ir/node.h b/cinn/ir/node.h
index 4b9e5b6c8471f..dbeea4f5b903e 100644
--- a/cinn/ir/node.h
+++ b/cinn/ir/node.h
@@ -44,9 +44,8 @@ class IRVisitor;
 
 #define NODETY_FORALL(macro__)          \
   NODETY_PRIMITIVE_TYPE_FOR_EACH(__m)   \
-NODETY_OP_FOR_EACH(__m)                 \
-NODETY_CONTROL_OP_FOR_EACH(__m)
-
+  NODETY_OP_FOR_EACH(__m)               \
+  NODETY_CONTROL_OP_FOR_EACH(__m)
 // clang-format on
 
 //! Define IrNodeTy
@@ -56,12 +55,14 @@ enum class IrNodeTy { NODETY_FORALL(__m) };
 #undef __m
 // @}
 
+std::ostream& operator<<(std::ostream& os, IrNodeTy type);
+
 class IRNode : public std::enable_shared_from_this<IRNode> {
  public:
   IRNode() = default;
   virtual ~IRNode() = default;
 
-  virtual void Accept(IRVisitor* v) const = 0;
+  virtual void Accept(IRVisitor* v) const {}
   virtual IrNodeTy node_type() = 0;
   virtual const Type& type() = 0;
 
@@ -88,7 +89,7 @@ class IRHandle : public std::enable_shared_from_this<IRHandle> {
   }
   template <typename T>
   T* As() {
-    if (node_type() == T::_type_info_) return static_cast<T*>(ptr_.get());
+    if (node_type() == T::_node_type_) return static_cast<T*>(ptr_.get());
     return nullptr;
   }
 
@@ -110,11 +111,9 @@ struct ExprNode : public IRNode {
   T* self() { return static_cast<T*>(this); }
   const T* const_self() const { return static_cast<const T*>(this); }
 
-  IrNodeTy node_type() { return _node_type_; }
+  IrNodeTy node_type() { return T::_node_type_; }
   const Type& type() { return type_; }
 
-  static IrNodeTy _node_type_;
-
  private:
   Type type_;
 };
@@ -158,6 +157,8 @@ struct Expr : public IRHandle {
  public:
   Expr() = default;
   Expr(const Expr& other) : IRHandle(other.ptr()) {}
+  Expr(const std::shared_ptr<IRNode>& p) : IRHandle(p) {}
+  void operator=(const std::shared_ptr<IRNode>& p) { ptr_ = p; }
 
   //! Helper function to construct numeric constants of various types.
   // @{
diff --git a/cinn/utils/CMakeLists.txt b/cinn/utils/CMakeLists.txt
new file mode 100644
index 0000000000000..49a0cb46668ef
--- /dev/null
+++ b/cinn/utils/CMakeLists.txt
@@ -0,0 +1 @@
+cc_library(utils SRCS string.cc)
diff --git a/cinn/utils/string.cc b/cinn/utils/string.cc
new file mode 100644
index 0000000000000..c6a02896da1b5
--- /dev/null
+++ b/cinn/utils/string.cc
@@ -0,0 +1,5 @@
+#include "cinn/utils/string.h"
+
+namespace cinn {
+namespace utils {}  // namespace utils
+}  // namespace cinn
diff --git a/cinn/utils/string.h b/cinn/utils/string.h
new file mode 100644
index 0000000000000..35eb0eee0b0bd
--- /dev/null
+++ b/cinn/utils/string.h
@@ -0,0 +1,17 @@
+#pragma once
+#include <sstream>
+#include <string>
+
+namespace cinn {
+namespace utils {
+
+//! Get the content of a stream.
+template <typename T>
+std::string GetStreamCnt(const T& x) {
+  std::stringstream os;
+  os << x;
+  return os.str();
+}
+
+}  // namespace utils
+}  // namespace cinn
diff --git a/cmake/core.cmake b/cmake/core.cmake
index 0830cd1888def..31157d28ca3ac 100644
--- a/cmake/core.cmake
+++ b/cmake/core.cmake
@@ -39,7 +39,7 @@ function(cc_library TARGET_NAME)
   (NOT ("${TARGET_NAME}" STREQUAL "cinn_lib"))
   )
     message(STATUS "xxxxx target:${TARGET_NAME}")
-    target_link_libraries(${TARGET_NAME} ${isl_lib})
+    target_link_libraries(${TARGET_NAME} ${isl_lib} Threads::Threads)
 
   endif (
   (NOT ("${TARGET_NAME}" STREQUAL "cinn_gtest_main"))  AND