diff --git a/include/IR/IR.h b/include/IR/IR.h
new file mode 100644
index 0000000..083308b
--- /dev/null
+++ b/include/IR/IR.h
@@ -0,0 +1,3 @@
+#pragma once
+#include "IR_basic.h"
+#include "IRBuilder.h"
\ No newline at end of file
diff --git a/include/IR/IRBuilder.h b/include/IR/IRBuilder.h
new file mode 100644
index 0000000..4001b9f
--- /dev/null
+++ b/include/IR/IRBuilder.h
@@ -0,0 +1,54 @@
+#include <memory>
+#include "IR_basic.h"
+#include "ast/astnode_visitor.h"
+class IRBuilder : public ASTNodeVirturalVisitor {
+  std::shared_ptr<ModuleItem> prog;
+
+ public:
+  // Structural AST Nodes
+  void ActuralVisit(FuncDef_ASTNode *node) override;
+  void ActuralVisit(ClassDef_ASTNode *node) override;
+  void ActuralVisit(Program_ASTNode *node) override;
+
+  // Statement AST Nodes
+  void ActuralVisit(EmptyStatement_ASTNode *node) override;
+  void ActuralVisit(DefinitionStatement_ASTNode *node) override;
+  void ActuralVisit(ExprStatement_ASTNode *node) override;
+  void ActuralVisit(IfStatement_ASTNode *node) override;
+  void ActuralVisit(WhileStatement_ASTNode *node) override;
+  void ActuralVisit(ForStatement_ASTNode *node) override;
+  void ActuralVisit(JmpStatement_ASTNode *node) override;
+  void ActuralVisit(SuiteStatement_ASTNode *node) override;
+
+  // Expression AST Nodes
+  void ActuralVisit(NewArrayExpr_ASTNode *node) override;
+  void ActuralVisit(NewConstructExpr_ASTNode *node) override;
+  void ActuralVisit(NewExpr_ASTNode *node) override;
+  void ActuralVisit(AccessExpr_ASTNode *node) override;
+  void ActuralVisit(IndexExpr_ASTNode *node) override;
+  void ActuralVisit(SuffixExpr_ASTNode *node) override;
+  void ActuralVisit(PrefixExpr_ASTNode *node) override;
+  void ActuralVisit(OppositeExpr_ASTNode *node) override;
+  void ActuralVisit(LNotExpr_ASTNode *node) override;
+  void ActuralVisit(BNotExpr_ASTNode *node) override;
+  void ActuralVisit(MDMExpr_ASTNode *node) override;
+  void ActuralVisit(PMExpr_ASTNode *node) override;
+  void ActuralVisit(RLExpr_ASTNode *node) override;
+  void ActuralVisit(GGLLExpr_ASTNode *node) override;
+  void ActuralVisit(NEExpr_ASTNode *node) override;
+  void ActuralVisit(BAndExpr_ASTNode *node) override;
+  void ActuralVisit(BXorExpr_ASTNode *node) override;
+  void ActuralVisit(BOrExpr_ASTNode *node) override;
+  void ActuralVisit(LAndExpr_ASTNode *node) override;
+  void ActuralVisit(LOrExpr_ASTNode *node) override;
+  void ActuralVisit(TernaryExpr_ASTNode *node) override;
+  void ActuralVisit(AssignExpr_ASTNode *node) override;
+  void ActuralVisit(ThisExpr_ASTNode *node) override;
+  void ActuralVisit(ParenExpr_ASTNode *node) override;
+  void ActuralVisit(IDExpr_ASTNode *node) override;
+  void ActuralVisit(FunctionCallExpr_ASTNode *node) override;
+  void ActuralVisit(FormattedStringExpr_ASTNode *node) override;
+  void ActuralVisit(ConstantExpr_ASTNode *node) override;
+};
+
+std::shared_ptr<ModuleItem> BuildIR(std::shared_ptr<Program_ASTNode> src);
\ No newline at end of file
diff --git a/include/IR/IR_basic.h b/include/IR/IR_basic.h
new file mode 100644
index 0000000..d9f6fe5
--- /dev/null
+++ b/include/IR/IR_basic.h
@@ -0,0 +1,143 @@
+#pragma once
+#include <ios>
+#include <memory>
+#include <string>
+#include <variant>
+#include <vector>
+#include "ast/astnode.h"
+struct LLVMIRIntType {
+  size_t bits;
+};
+struct LLVMIRPTRType {};
+struct LLVMIRCLASSTYPE {};
+using LLVMType = std::variant<LLVMIRIntType, LLVMIRPTRType, LLVMIRCLASSTYPE>;
+class LLVMIRItemBase {
+ public:
+  LLVMIRItemBase() = default;
+  virtual ~LLVMIRItemBase() = default;
+  virtual void RecursivePrint(std::ostream &os) const;
+};
+
+class TypeDefItem : public LLVMIRItemBase {
+ public:
+  void RecursivePrint(std::ostream &os) const { ; }
+};
+class GlobalVarDefItem : public LLVMIRItemBase {
+  LLVMType type;
+  std::string name;
+
+ public:
+  void RecursivePrint(std::ostream &os) const { ; }
+};
+class ActionItem : public LLVMIRItemBase {
+ public:
+  void RecursivePrint(std::ostream &os) const { ; }
+};
+class JMPActionItem : public ActionItem {
+  std::string label;
+ public:
+  void RecursivePrint(std::ostream &os) const { ; }
+};
+class BRAction: public JMPActionItem {
+  std::string cond;
+  std::string true_label;
+  std::string false_label;
+ public:
+  void RecursivePrint(std::ostream &os) const { ; }
+};
+class UNConditionJMPAction: public JMPActionItem {
+  std::string label;
+ public:
+  void RecursivePrint(std::ostream &os) const { ; }
+};
+class RETAction : public JMPActionItem {
+  std::string value;
+ public:
+  void RecursivePrint(std::ostream &os) const { ; }
+};
+class BinaryOperationAction : public ActionItem {
+  std::string op;
+  std::string lhs;
+  std::string rhs;
+  std::string result;
+  LLVMType type;
+ public:
+  void RecursivePrint(std::ostream &os) const { ; }
+};
+class AllocaAction : public ActionItem {
+  std::string name;
+  LLVMType type;
+  size_t num;
+ public:
+  void RecursivePrint(std::ostream &os) const { ; }
+};
+class LoadAction : public ActionItem {
+  std::string result;
+  LLVMType ty;
+  std::string ptr;
+ public:
+  void RecursivePrint(std::ostream &os) const { ; }
+};
+class StoreAction : public ActionItem {
+  LLVMType ty;
+  std::string value;
+  std::string ptr;
+ public:
+  void RecursivePrint(std::ostream &os) const { ; }
+};
+class GetElementPtrAction : public ActionItem {
+  std::string result;
+  LLVMType ty;
+  std::string ptr;
+  std::vector<std::string> indices;
+ public:
+  void RecursivePrint(std::ostream &os) const { ; }
+};
+class ICMPAction : public ActionItem {
+  std::string op;
+  std::string lhs;
+  std::string rhs;
+  std::string result;
+  LLVMType ty;
+ public:
+  void RecursivePrint(std::ostream &os) const { ; }
+};
+class BlockItem : public LLVMIRItemBase {
+  std::string label;
+  std::vector<std::shared_ptr<ActionItem>> actions;
+  std::shared_ptr<JMPActionItem> exit_action;
+ public:
+  void RecursivePrint(std::ostream &os) const { ; }
+};
+class FunctionDefItem : public LLVMIRItemBase {
+  std::vector<std::shared_ptr<BlockItem>> basic_blocks;
+
+ public:
+  void RecursivePrint(std::ostream &os) const {
+    for (auto &item : basic_blocks) {
+      item->RecursivePrint(os);
+      os << '\n';
+    }
+  }
+};
+class ModuleItem : public LLVMIRItemBase {
+  std::vector<std::shared_ptr<TypeDefItem>> type_defs;
+  std::vector<std::shared_ptr<GlobalVarDefItem>> global_var_defs;
+  std::vector<std::shared_ptr<FunctionDefItem>> function_defs;
+
+ public:
+  void RecursivePrint(std::ostream &os) const {
+    for (auto &item : type_defs) {
+      item->RecursivePrint(os);
+      os << '\n';
+    }
+    for (auto &item : global_var_defs) {
+      item->RecursivePrint(os);
+      os << '\n';
+    }
+    for (auto &item : function_defs) {
+      item->RecursivePrint(os);
+      os << '\n';
+    }
+  }
+};
\ No newline at end of file
diff --git a/include/ast/ast.h b/include/ast/ast.h
index 5997c1a..39f868f 100644
--- a/include/ast/ast.h
+++ b/include/ast/ast.h
@@ -2,6 +2,7 @@
 #define AST_H
 #include "astnode.h"
 #include "astnode_visitor.h"
+#include "semantic_visitor.h"
 #include "expr_astnode.h"
 #include "statement_astnode.h"
 #include "structural_astnode.h"
diff --git a/include/ast/astnode_visitor.h b/include/ast/astnode_visitor.h
index 5869d9c..32d37c7 100644
--- a/include/ast/astnode_visitor.h
+++ b/include/ast/astnode_visitor.h
@@ -54,67 +54,4 @@ class ASTNodeVirturalVisitor : public ASTNodeVisitorBase {
   virtual void ActuralVisit(ConstantExpr_ASTNode *node) = 0;
 };
 
-class ASTSemanticCheckVisitor : public ASTNodeVirturalVisitor {
-  bool is_in_func_def;
-  bool has_return;
-  FunctionSchema cur_func_schema;
-  std::string cur_class_name;
-  bool is_in_class_def;
-  size_t loop_level;
-  std::shared_ptr<GlobalScope> global_scope;
-  friend std::shared_ptr<Program_ASTNode> CheckAndDecorate(std::shared_ptr<Program_ASTNode> src);
-
-  bool ClassExists(const std::string &name) {
-    if (name == "int" || name == "bool") return true;
-    return global_scope->classes.find(name) != global_scope->classes.end();
-  }
-
- public:
-  ASTSemanticCheckVisitor() : is_in_func_def(false), loop_level(0) {}
-  // Structural AST Nodes
-  void ActuralVisit(FuncDef_ASTNode *node) override;
-  void ActuralVisit(ClassDef_ASTNode *node) override;
-  void ActuralVisit(Program_ASTNode *node) override;
-
-  // Statement AST Nodes
-  void ActuralVisit(EmptyStatement_ASTNode *node) override;
-  void ActuralVisit(DefinitionStatement_ASTNode *node) override;
-  void ActuralVisit(ExprStatement_ASTNode *node) override;
-  void ActuralVisit(IfStatement_ASTNode *node) override;
-  void ActuralVisit(WhileStatement_ASTNode *node) override;
-  void ActuralVisit(ForStatement_ASTNode *node) override;
-  void ActuralVisit(JmpStatement_ASTNode *node) override;
-  void ActuralVisit(SuiteStatement_ASTNode *node) override;
-
-  // Expression AST Nodes
-  void ActuralVisit(NewArrayExpr_ASTNode *node) override;
-  void ActuralVisit(NewConstructExpr_ASTNode *node) override;
-  void ActuralVisit(NewExpr_ASTNode *node) override;
-  void ActuralVisit(AccessExpr_ASTNode *node) override;
-  void ActuralVisit(IndexExpr_ASTNode *node) override;
-  void ActuralVisit(SuffixExpr_ASTNode *node) override;
-  void ActuralVisit(PrefixExpr_ASTNode *node) override;
-  void ActuralVisit(OppositeExpr_ASTNode *node) override;
-  void ActuralVisit(LNotExpr_ASTNode *node) override;
-  void ActuralVisit(BNotExpr_ASTNode *node) override;
-  void ActuralVisit(MDMExpr_ASTNode *node) override;
-  void ActuralVisit(PMExpr_ASTNode *node) override;
-  void ActuralVisit(RLExpr_ASTNode *node) override;
-  void ActuralVisit(GGLLExpr_ASTNode *node) override;
-  void ActuralVisit(NEExpr_ASTNode *node) override;
-  void ActuralVisit(BAndExpr_ASTNode *node) override;
-  void ActuralVisit(BXorExpr_ASTNode *node) override;
-  void ActuralVisit(BOrExpr_ASTNode *node) override;
-  void ActuralVisit(LAndExpr_ASTNode *node) override;
-  void ActuralVisit(LOrExpr_ASTNode *node) override;
-  void ActuralVisit(TernaryExpr_ASTNode *node) override;
-  void ActuralVisit(AssignExpr_ASTNode *node) override;
-  void ActuralVisit(ThisExpr_ASTNode *node) override;
-  void ActuralVisit(ParenExpr_ASTNode *node) override;
-  void ActuralVisit(IDExpr_ASTNode *node) override;
-  void ActuralVisit(FunctionCallExpr_ASTNode *node) override;
-  void ActuralVisit(FormattedStringExpr_ASTNode *node) override;
-  void ActuralVisit(ConstantExpr_ASTNode *node) override;
-};
-
 #endif  // ASTNODE_ActuralVisitOR_H
\ No newline at end of file
diff --git a/include/ast/scope.hpp b/include/ast/scope.hpp
index 6a1cf45..4899078 100644
--- a/include/ast/scope.hpp
+++ b/include/ast/scope.hpp
@@ -17,6 +17,7 @@ class ScopeBase {
 
  protected:
   ScopeBase *parent;  // cannot use std::shared_ptr<ScopeBase> because of circular dependency
+  size_t scope_id;
   virtual bool VariableNameAvailable(const std::string &name, int ttl) = 0;
   virtual bool add_variable(const std::string &name, const ExprTypeInfo &type) = 0;
   virtual ExprTypeInfo fetch_varaible(const std::string &name) = 0;
@@ -26,6 +27,11 @@ class ScopeBase {
                                                              "for",  "while", "break", "continue", "return"};
     return keywords.find(name) != keywords.end();
   }
+  public:
+  ScopeBase() {
+    static size_t scope_counter=0;
+    scope_id = scope_counter++;
+  }
 };
 class LocalScope : public ScopeBase {
   friend class Visitor;
@@ -104,6 +110,7 @@ class ClassDefScope : public ScopeBase {
   friend std::shared_ptr<Program_ASTNode> CheckAndDecorate(std::shared_ptr<Program_ASTNode> src);
   std::unordered_map<std::string, ExprTypeInfo> member_variables;
   std::unordered_map<std::string, std::shared_ptr<FunctionScope>> member_functions;
+  IRClassInfo llvm_class_info;
   bool add_variable(const std::string &name, const ExprTypeInfo &type) override {
     if (!VariableNameAvailable(name, 0)) {
       return false;
diff --git a/include/ast/semantic_visitor.h b/include/ast/semantic_visitor.h
new file mode 100644
index 0000000..521cc71
--- /dev/null
+++ b/include/ast/semantic_visitor.h
@@ -0,0 +1,69 @@
+#pragma once
+#include "astnode.h"
+#include "expr_astnode.h"
+#include "statement_astnode.h"
+#include "structural_astnode.h"
+#include "astnode_visitor.h"
+
+class ASTSemanticCheckVisitor : public ASTNodeVirturalVisitor {
+  bool is_in_func_def;
+  bool has_return;
+  FunctionSchema cur_func_schema;
+  std::string cur_class_name;
+  bool is_in_class_def;
+  size_t loop_level;
+  std::shared_ptr<GlobalScope> global_scope;
+  friend std::shared_ptr<Program_ASTNode> CheckAndDecorate(std::shared_ptr<Program_ASTNode> src);
+
+  bool ClassExists(const std::string &name) {
+    if (name == "int" || name == "bool") return true;
+    return global_scope->classes.find(name) != global_scope->classes.end();
+  }
+
+ public:
+  ASTSemanticCheckVisitor() : is_in_func_def(false), loop_level(0) {}
+  // Structural AST Nodes
+  void ActuralVisit(FuncDef_ASTNode *node) override;
+  void ActuralVisit(ClassDef_ASTNode *node) override;
+  void ActuralVisit(Program_ASTNode *node) override;
+
+  // Statement AST Nodes
+  void ActuralVisit(EmptyStatement_ASTNode *node) override;
+  void ActuralVisit(DefinitionStatement_ASTNode *node) override;
+  void ActuralVisit(ExprStatement_ASTNode *node) override;
+  void ActuralVisit(IfStatement_ASTNode *node) override;
+  void ActuralVisit(WhileStatement_ASTNode *node) override;
+  void ActuralVisit(ForStatement_ASTNode *node) override;
+  void ActuralVisit(JmpStatement_ASTNode *node) override;
+  void ActuralVisit(SuiteStatement_ASTNode *node) override;
+
+  // Expression AST Nodes
+  void ActuralVisit(NewArrayExpr_ASTNode *node) override;
+  void ActuralVisit(NewConstructExpr_ASTNode *node) override;
+  void ActuralVisit(NewExpr_ASTNode *node) override;
+  void ActuralVisit(AccessExpr_ASTNode *node) override;
+  void ActuralVisit(IndexExpr_ASTNode *node) override;
+  void ActuralVisit(SuffixExpr_ASTNode *node) override;
+  void ActuralVisit(PrefixExpr_ASTNode *node) override;
+  void ActuralVisit(OppositeExpr_ASTNode *node) override;
+  void ActuralVisit(LNotExpr_ASTNode *node) override;
+  void ActuralVisit(BNotExpr_ASTNode *node) override;
+  void ActuralVisit(MDMExpr_ASTNode *node) override;
+  void ActuralVisit(PMExpr_ASTNode *node) override;
+  void ActuralVisit(RLExpr_ASTNode *node) override;
+  void ActuralVisit(GGLLExpr_ASTNode *node) override;
+  void ActuralVisit(NEExpr_ASTNode *node) override;
+  void ActuralVisit(BAndExpr_ASTNode *node) override;
+  void ActuralVisit(BXorExpr_ASTNode *node) override;
+  void ActuralVisit(BOrExpr_ASTNode *node) override;
+  void ActuralVisit(LAndExpr_ASTNode *node) override;
+  void ActuralVisit(LOrExpr_ASTNode *node) override;
+  void ActuralVisit(TernaryExpr_ASTNode *node) override;
+  void ActuralVisit(AssignExpr_ASTNode *node) override;
+  void ActuralVisit(ThisExpr_ASTNode *node) override;
+  void ActuralVisit(ParenExpr_ASTNode *node) override;
+  void ActuralVisit(IDExpr_ASTNode *node) override;
+  void ActuralVisit(FunctionCallExpr_ASTNode *node) override;
+  void ActuralVisit(FormattedStringExpr_ASTNode *node) override;
+  void ActuralVisit(ConstantExpr_ASTNode *node) override;
+};
\ No newline at end of file
diff --git a/include/tools.h b/include/tools.h
index cbc7b9e..4491ae2 100644
--- a/include/tools.h
+++ b/include/tools.h
@@ -1,6 +1,8 @@
 #pragma once
 #include <stdexcept>
+#include <unordered_map>
 #include <variant>
+#include <vector>
 enum class ASTNodeType {
   // Expression nodes
   NewArrayExpr,
@@ -98,4 +100,38 @@ inline bool operator==(const ExprTypeInfo &l, const ExprTypeInfo &r) {
   }
   throw std::runtime_error("something strange happened");
 }
-inline bool operator!=(const ExprTypeInfo &l, const ExprTypeInfo &r) { return !(l == r); }
\ No newline at end of file
+inline bool operator!=(const ExprTypeInfo &l, const ExprTypeInfo &r) { return !(l == r); }
+
+class IRClassInfo {
+ public:
+  std::string class_name;               // This data must be provided by user
+  std::vector<size_t> member_var_size;  // This data must be provided by user. Each of them is the size of a member
+                                        // variable, which must be in [1,4]
+  std::unordered_map<std::string, size_t> member_var_offset;  // This data must be provided by user
+  std::vector<size_t> member_var_pos_after_align;
+  size_t class_size_after_align;
+  void ArrangeSpace() {
+    size_t cur_pos = 0;
+    size_t align_size = 1;
+    for (size_t cur_size : member_var_size) {
+      if (cur_size != 1 && cur_size != 4) throw std::runtime_error("Invalid member variable size");
+      if (cur_pos % cur_size == 0) {
+        member_var_pos_after_align.push_back(cur_pos);
+        cur_pos += cur_size;
+      } else {
+        cur_pos += cur_size - (cur_pos % cur_size);
+        member_var_pos_after_align.push_back(cur_pos);
+        cur_pos += cur_size;
+      }
+      if (cur_size > align_size) align_size = cur_size;
+      if (cur_pos % align_size != 0) cur_pos += align_size - (cur_pos % align_size);
+      class_size_after_align = cur_pos;
+    }
+  }
+};
+class IRVariableInfo {
+ public:
+  enum class VariableType { global_variable, local_variable, member_variable };
+  std::string class_name;
+  std::string variable_name;
+};
\ No newline at end of file
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index dbeb12c..9bee807 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -1,7 +1,8 @@
 add_subdirectory(ast)
 add_subdirectory(semantic)
+add_subdirectory(IR)
 add_executable(zmxcc main.cpp)
-target_link_libraries(zmxcc semantic argparse)
+target_link_libraries(zmxcc semantic argparse IR)
 set_target_properties(zmxcc PROPERTIES
   RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}"
 )
\ No newline at end of file
diff --git a/src/IR/CMakeLists.txt b/src/IR/CMakeLists.txt
new file mode 100644
index 0000000..33ea9b2
--- /dev/null
+++ b/src/IR/CMakeLists.txt
@@ -0,0 +1,5 @@
+include_directories(${CMAKE_SOURCE_DIR}/include/IR)
+file(GLOB IR_SOURCES "*.cpp")
+
+add_library(IR STATIC ${IR_SOURCES})
+target_link_libraries(IR PUBLIC ast)
\ No newline at end of file
diff --git a/src/IR/IRBuilder.cpp b/src/IR/IRBuilder.cpp
new file mode 100644
index 0000000..9f37587
--- /dev/null
+++ b/src/IR/IRBuilder.cpp
@@ -0,0 +1,167 @@
+#include "IRBuilder.h"
+#include <stdexcept>
+
+// Structural AST Nodes
+void IRBuilder::ActuralVisit(FuncDef_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(ClassDef_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(Program_ASTNode *node) {
+  // TODO: Implement function body
+  throw std::runtime_error("IRBuilder not implemented");
+}
+
+// Statement AST Nodes
+void IRBuilder::ActuralVisit(EmptyStatement_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(DefinitionStatement_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(ExprStatement_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(IfStatement_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(WhileStatement_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(ForStatement_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(JmpStatement_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(SuiteStatement_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+// Expression AST Nodes
+void IRBuilder::ActuralVisit(NewArrayExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(NewConstructExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(NewExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(AccessExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(IndexExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(SuffixExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(PrefixExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(OppositeExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(LNotExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(BNotExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(MDMExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(PMExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(RLExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(GGLLExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(NEExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(BAndExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(BXorExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(BOrExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(LAndExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(LOrExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(TernaryExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(AssignExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(ThisExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(ParenExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(IDExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(FunctionCallExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(FormattedStringExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+void IRBuilder::ActuralVisit(ConstantExpr_ASTNode *node) {
+  // TODO: Implement function body
+}
+
+std::shared_ptr<ModuleItem> BuildIR(std::shared_ptr<Program_ASTNode> src) {
+  IRBuilder visitor;
+  visitor.visit(src.get());
+}
\ No newline at end of file
diff --git a/src/IR/build.sh b/src/IR/build.sh
new file mode 100755
index 0000000..e02155f
--- /dev/null
+++ b/src/IR/build.sh
@@ -0,0 +1,10 @@
+#!/bin/bash
+# Get the directory of the script
+SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )"
+# Change to the script directory
+cd "$SCRIPT_DIR"
+clang-18 -S -emit-llvm --target=riscv32-unknown-elf -O2 -fno-builtin-printf -fno-builtin-memcpy \
+        builtin.c -o builtin_intermediate.ll
+sed 's/_builtin_/.builtin./g;s/string_/string./g;s/array_/array./g' builtin_intermediate.ll > builtin.ll
+rm builtin_intermediate.ll
+llc-18 -march=riscv32 builtin.ll -o builtin.s -O2
\ No newline at end of file
diff --git a/src/IR/builtin.c b/src/IR/builtin.c
new file mode 100644
index 0000000..e8490d3
--- /dev/null
+++ b/src/IR/builtin.c
@@ -0,0 +1,130 @@
+#include <stdarg.h>
+#define bool _Bool
+#define EOF (-1)
+// libc function
+void* malloc(unsigned int size);
+void free(void* ptr);
+int printf(const char *pattern, ...);
+int scanf(const char *format, ...);
+int sprintf(char *str, const char *pattern, ...);
+int sscanf(const char *str, const char *pattern, ...);
+int string_length(char *self) {
+  int res=0;
+  while(self[res]!='\0') {
+    res++;
+  }
+  return res;
+}
+char* string_substring(char *self,int left, int right) {
+  int len = right - left;
+  char *res = (char*)malloc(len+1);
+  for(int i=0;i<len;i++) {
+    res[i] = self[left+i];
+  }
+  res[len] = '\0';
+  return res;
+}
+int string_parseInt(char *self) {
+  int res;
+  sscanf(self, "%d", &res);
+  return res;
+}
+int string_ord(char *self, int index) {
+  return self[index];
+}
+void print(char *str) {
+  printf("%s", str);
+}
+void println(char *str) {
+  printf("%s\n", str);
+}
+void printInt(int n) {
+  printf("%d", n);
+}
+void printlnInt(int n) {
+  printf("%d\n", n);
+}
+char* toString(int n) {
+  char *res = (char*)malloc(15);
+  sprintf(res, "%d", n);
+  return res;
+}
+char* getString() { // same as getline
+  char *res=(char*)malloc(11);
+  int allocated_length = 10;
+  int cur_length = 0;
+  char ch;
+  while(scanf("%c",&ch)==1) {
+    if(ch=='\n'||ch=='\r') break;
+    if(cur_length==allocated_length) {
+      char *new_res = (char*)malloc(allocated_length*2+1);
+      for(int i=0;i<allocated_length;i++) {
+        new_res[i] = res[i];
+      }
+      free(res);
+      res = new_res;
+      allocated_length *= 2;
+    }
+    res[cur_length++] = ch;
+  }
+  res[cur_length] = '\0';
+  return res;
+}
+int getInt() {
+  int res;
+  scanf("%d", &res);
+  return res;
+}
+
+void* _builtin_AllocateClassBody(int size) {
+  return malloc(size);
+}
+
+int _builtin_GetArrayLength(void* array) {
+  int res=0;
+  array=((char*)array)-4;
+  res|=(((unsigned char*)array)[0]);
+  res|=((unsigned int)(((unsigned char*)array)[1])<<8);
+  res|=((unsigned int)(((unsigned char*)array)[2])<<16);
+  res|=((unsigned int)(((unsigned char*)array)[3])<<24);
+  return res;
+}
+void* _builtin_RecursiveAllocateArray(int dims_with_size, int element_size, int* dim_size) {
+  void* res;
+  if(dims_with_size==1) {
+    res=malloc(dim_size[0]*element_size+4);
+    ((unsigned char*)res)[0] = dim_size[0]&0xff;
+    ((unsigned char*)res)[1] = (dim_size[0]>>8)&0xff;
+    ((unsigned char*)res)[2] = (dim_size[0]>>16)&0xff;
+    ((unsigned char*)res)[3] = (dim_size[0]>>24)&0xff;
+    void* actual_space=((char*)res)+4;
+    res=actual_space;
+  } else {
+    res=malloc(dim_size[0]*sizeof(void*)+4);
+    ((unsigned char*)res)[0] = dim_size[0]&0xff;
+    ((unsigned char*)res)[1] = (dim_size[0]>>8)&0xff;
+    ((unsigned char*)res)[2] = (dim_size[0]>>16)&0xff;
+    ((unsigned char*)res)[3] = (dim_size[0]>>24)&0xff;
+    void* actual_space=((char*)res)+4;
+    for(int i=0;i<dim_size[0];i++) {
+      ((void**)actual_space)[i] = _builtin_RecursiveAllocateArray(dims_with_size-1, element_size, dim_size+1);
+    }
+    res=actual_space;
+  }
+  return res;
+}
+// void* _builtin_AllocateArray(int total_dimensions,int basic_element_size,...) {
+//   va_list args;
+//   va_start(args, basic_element_size);
+//   int* dim_size=(int*)malloc(total_dimensions*sizeof(int));
+//   int dims_with_size=0;
+//   for(int i=0;i<total_dimensions;i++) {
+//     dim_size[i] = va_arg(args, int);
+//     if(dim_size[i]>=0) dims_with_size++;
+//   }
+//   if(dims_with_size<total_dimensions) basic_element_size = sizeof(void*);
+//   va_end(args);
+//   void* res=_builtin_RecursiveAllocateArray(dims_with_size, basic_element_size, dim_size);
+//   free(dim_size);
+//   return res;
+// }
\ No newline at end of file
diff --git a/src/IR/builtin.ll b/src/IR/builtin.ll
new file mode 100644
index 0000000..f35695f
--- /dev/null
+++ b/src/IR/builtin.ll
@@ -0,0 +1,327 @@
+; ModuleID = 'builtin.c'
+source_filename = "builtin.c"
+target datalayout = "e-m:e-p:32:32-i64:64-n32-S128"
+target triple = "riscv32-unknown-unknown-elf"
+
+@.str = private unnamed_addr constant [3 x i8] c"%d\00", align 1
+@.str.1 = private unnamed_addr constant [3 x i8] c"%s\00", align 1
+@.str.2 = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
+@.str.3 = private unnamed_addr constant [4 x i8] c"%d\0A\00", align 1
+@.str.4 = private unnamed_addr constant [3 x i8] c"%c\00", align 1
+
+; Function Attrs: nofree norecurse nosync nounwind memory(argmem: read)
+define dso_local i32 @string.length(ptr nocapture noundef readonly %0) local_unnamed_addr #0 {
+  br label %2
+
+2:                                                ; preds = %2, %1
+  %3 = phi i32 [ 0, %1 ], [ %7, %2 ]
+  %4 = getelementptr inbounds i8, ptr %0, i32 %3
+  %5 = load i8, ptr %4, align 1, !tbaa !6
+  %6 = icmp eq i8 %5, 0
+  %7 = add nuw nsw i32 %3, 1
+  br i1 %6, label %8, label %2, !llvm.loop !9
+
+8:                                                ; preds = %2
+  ret i32 %3
+}
+
+; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
+declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1
+
+; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
+declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1
+
+; Function Attrs: nofree nounwind memory(write, argmem: read, inaccessiblemem: readwrite)
+define dso_local noalias noundef ptr @string.substring(ptr nocapture noundef readonly %0, i32 noundef %1, i32 noundef %2) local_unnamed_addr #2 {
+  %4 = sub nsw i32 %2, %1
+  %5 = add nsw i32 %4, 1
+  %6 = tail call ptr @malloc(i32 noundef %5) #10
+  %7 = getelementptr i8, ptr %0, i32 %1
+  %8 = icmp sgt i32 %4, 0
+  br i1 %8, label %11, label %9
+
+9:                                                ; preds = %11, %3
+  %10 = getelementptr inbounds i8, ptr %6, i32 %4
+  store i8 0, ptr %10, align 1, !tbaa !6
+  ret ptr %6
+
+11:                                               ; preds = %3, %11
+  %12 = phi i32 [ %16, %11 ], [ 0, %3 ]
+  %13 = getelementptr i8, ptr %7, i32 %12
+  %14 = load i8, ptr %13, align 1, !tbaa !6
+  %15 = getelementptr inbounds i8, ptr %6, i32 %12
+  store i8 %14, ptr %15, align 1, !tbaa !6
+  %16 = add nuw nsw i32 %12, 1
+  %17 = icmp eq i32 %16, %4
+  br i1 %17, label %9, label %11, !llvm.loop !11
+}
+
+; Function Attrs: mustprogress nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite)
+declare dso_local noalias noundef ptr @malloc(i32 noundef) local_unnamed_addr #3
+
+; Function Attrs: nofree nounwind
+define dso_local i32 @string.parseInt(ptr nocapture noundef readonly %0) local_unnamed_addr #4 {
+  %2 = alloca i32, align 4
+  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %2) #11
+  %3 = call i32 (ptr, ptr, ...) @sscanf(ptr noundef %0, ptr noundef nonnull @.str, ptr noundef nonnull %2) #12
+  %4 = load i32, ptr %2, align 4, !tbaa !12
+  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %2) #11
+  ret i32 %4
+}
+
+; Function Attrs: nofree nounwind
+declare dso_local noundef i32 @sscanf(ptr nocapture noundef readonly, ptr nocapture noundef readonly, ...) local_unnamed_addr #4
+
+; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(argmem: read)
+define dso_local i32 @string.ord(ptr nocapture noundef readonly %0, i32 noundef %1) local_unnamed_addr #5 {
+  %3 = getelementptr inbounds i8, ptr %0, i32 %1
+  %4 = load i8, ptr %3, align 1, !tbaa !6
+  %5 = zext i8 %4 to i32
+  ret i32 %5
+}
+
+; Function Attrs: nounwind
+define dso_local void @print(ptr noundef %0) local_unnamed_addr #6 {
+  %2 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull @.str.1, ptr noundef %0) #13
+  ret void
+}
+
+declare dso_local i32 @printf(ptr noundef, ...) local_unnamed_addr #7
+
+; Function Attrs: nounwind
+define dso_local void @println(ptr noundef %0) local_unnamed_addr #6 {
+  %2 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull @.str.2, ptr noundef %0) #13
+  ret void
+}
+
+; Function Attrs: nounwind
+define dso_local void @printInt(i32 noundef %0) local_unnamed_addr #6 {
+  %2 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull @.str, i32 noundef %0) #13
+  ret void
+}
+
+; Function Attrs: nounwind
+define dso_local void @printlnInt(i32 noundef %0) local_unnamed_addr #6 {
+  %2 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull @.str.3, i32 noundef %0) #13
+  ret void
+}
+
+; Function Attrs: nofree nounwind
+define dso_local noalias noundef ptr @toString(i32 noundef %0) local_unnamed_addr #4 {
+  %2 = tail call dereferenceable_or_null(15) ptr @malloc(i32 noundef 15) #10
+  %3 = tail call i32 (ptr, ptr, ...) @sprintf(ptr noundef nonnull dereferenceable(1) %2, ptr noundef nonnull dereferenceable(1) @.str, i32 noundef %0) #12
+  ret ptr %2
+}
+
+; Function Attrs: nofree nounwind
+declare dso_local noundef i32 @sprintf(ptr noalias nocapture noundef writeonly, ptr nocapture noundef readonly, ...) local_unnamed_addr #4
+
+; Function Attrs: nounwind
+define dso_local noalias ptr @getString() local_unnamed_addr #6 {
+  %1 = alloca i8, align 1
+  %2 = tail call dereferenceable_or_null(11) ptr @malloc(i32 noundef 11) #10
+  call void @llvm.lifetime.start.p0(i64 1, ptr nonnull %1) #11
+  %3 = call i32 (ptr, ...) @scanf(ptr noundef nonnull @.str.4, ptr noundef nonnull %1) #12
+  %4 = icmp eq i32 %3, 1
+  br i1 %4, label %5, label %34
+
+5:                                                ; preds = %0, %26
+  %6 = phi ptr [ %29, %26 ], [ %2, %0 ]
+  %7 = phi i32 [ %30, %26 ], [ 0, %0 ]
+  %8 = phi i32 [ %28, %26 ], [ 10, %0 ]
+  %9 = load i8, ptr %1, align 1
+  switch i8 %9, label %10 [
+    i8 13, label %34
+    i8 10, label %34
+  ]
+
+10:                                               ; preds = %5
+  %11 = icmp eq i32 %7, %8
+  br i1 %11, label %12, label %26
+
+12:                                               ; preds = %10
+  %13 = shl nuw nsw i32 %7, 1
+  %14 = or disjoint i32 %13, 1
+  %15 = call ptr @malloc(i32 noundef %14) #10
+  %16 = icmp eq i32 %7, 0
+  br i1 %16, label %17, label %19
+
+17:                                               ; preds = %19, %12
+  call void @free(ptr noundef %6) #12
+  %18 = load i8, ptr %1, align 1, !tbaa !6
+  br label %26
+
+19:                                               ; preds = %12, %19
+  %20 = phi i32 [ %24, %19 ], [ 0, %12 ]
+  %21 = getelementptr inbounds i8, ptr %6, i32 %20
+  %22 = load i8, ptr %21, align 1, !tbaa !6
+  %23 = getelementptr inbounds i8, ptr %15, i32 %20
+  store i8 %22, ptr %23, align 1, !tbaa !6
+  %24 = add nuw nsw i32 %20, 1
+  %25 = icmp eq i32 %24, %7
+  br i1 %25, label %17, label %19, !llvm.loop !14
+
+26:                                               ; preds = %17, %10
+  %27 = phi i8 [ %18, %17 ], [ %9, %10 ]
+  %28 = phi i32 [ %13, %17 ], [ %8, %10 ]
+  %29 = phi ptr [ %15, %17 ], [ %6, %10 ]
+  %30 = add nuw nsw i32 %7, 1
+  %31 = getelementptr inbounds i8, ptr %29, i32 %7
+  store i8 %27, ptr %31, align 1, !tbaa !6
+  %32 = call i32 (ptr, ...) @scanf(ptr noundef nonnull @.str.4, ptr noundef nonnull %1) #12
+  %33 = icmp eq i32 %32, 1
+  br i1 %33, label %5, label %34, !llvm.loop !15
+
+34:                                               ; preds = %26, %5, %5, %0
+  %35 = phi i32 [ 0, %0 ], [ %7, %5 ], [ %7, %5 ], [ %30, %26 ]
+  %36 = phi ptr [ %2, %0 ], [ %6, %5 ], [ %6, %5 ], [ %29, %26 ]
+  %37 = getelementptr inbounds i8, ptr %36, i32 %35
+  store i8 0, ptr %37, align 1, !tbaa !6
+  call void @llvm.lifetime.end.p0(i64 1, ptr nonnull %1) #11
+  ret ptr %36
+}
+
+; Function Attrs: nofree nounwind
+declare dso_local noundef i32 @scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #4
+
+; Function Attrs: mustprogress nounwind willreturn allockind("free") memory(argmem: readwrite, inaccessiblemem: readwrite)
+declare dso_local void @free(ptr allocptr nocapture noundef) local_unnamed_addr #8
+
+; Function Attrs: nofree nounwind
+define dso_local i32 @getInt() local_unnamed_addr #4 {
+  %1 = alloca i32, align 4
+  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #11
+  %2 = call i32 (ptr, ...) @scanf(ptr noundef nonnull @.str, ptr noundef nonnull %1) #12
+  %3 = load i32, ptr %1, align 4, !tbaa !12
+  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #11
+  ret i32 %3
+}
+
+; Function Attrs: mustprogress nofree nounwind willreturn memory(inaccessiblemem: readwrite)
+define dso_local noalias noundef ptr @.builtin.AllocateClassBody(i32 noundef %0) local_unnamed_addr #9 {
+  %2 = tail call ptr @malloc(i32 noundef %0) #10
+  ret ptr %2
+}
+
+; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(argmem: read)
+define dso_local i32 @.builtin.GetArrayLength(ptr nocapture noundef readonly %0) local_unnamed_addr #5 {
+  %2 = getelementptr inbounds i8, ptr %0, i32 -4
+  %3 = load i8, ptr %2, align 1, !tbaa !6
+  %4 = zext i8 %3 to i32
+  %5 = getelementptr inbounds i8, ptr %0, i32 -3
+  %6 = load i8, ptr %5, align 1, !tbaa !6
+  %7 = zext i8 %6 to i32
+  %8 = shl nuw nsw i32 %7, 8
+  %9 = or disjoint i32 %8, %4
+  %10 = getelementptr inbounds i8, ptr %0, i32 -2
+  %11 = load i8, ptr %10, align 1, !tbaa !6
+  %12 = zext i8 %11 to i32
+  %13 = shl nuw nsw i32 %12, 16
+  %14 = or disjoint i32 %9, %13
+  %15 = getelementptr inbounds i8, ptr %0, i32 -1
+  %16 = load i8, ptr %15, align 1, !tbaa !6
+  %17 = zext i8 %16 to i32
+  %18 = shl nuw i32 %17, 24
+  %19 = or disjoint i32 %14, %18
+  ret i32 %19
+}
+
+; Function Attrs: nofree nounwind memory(write, argmem: read, inaccessiblemem: readwrite)
+define dso_local noalias nonnull ptr @.builtin.RecursiveAllocateArray(i32 noundef %0, i32 noundef %1, ptr nocapture noundef readonly %2) local_unnamed_addr #2 {
+  %4 = icmp eq i32 %0, 1
+  %5 = load i32, ptr %2, align 4, !tbaa !12
+  %6 = trunc i32 %5 to i8
+  %7 = lshr i32 %5, 8
+  %8 = trunc i32 %7 to i8
+  %9 = lshr i32 %5, 16
+  %10 = trunc i32 %9 to i8
+  %11 = lshr i32 %5, 24
+  %12 = trunc i32 %11 to i8
+  br i1 %4, label %13, label %21
+
+13:                                               ; preds = %3
+  %14 = mul nsw i32 %5, %1
+  %15 = add nsw i32 %14, 4
+  %16 = tail call ptr @malloc(i32 noundef %15) #10
+  store i8 %6, ptr %16, align 1, !tbaa !6
+  %17 = getelementptr inbounds i8, ptr %16, i32 1
+  store i8 %8, ptr %17, align 1, !tbaa !6
+  %18 = getelementptr inbounds i8, ptr %16, i32 2
+  store i8 %10, ptr %18, align 1, !tbaa !6
+  %19 = getelementptr inbounds i8, ptr %16, i32 3
+  store i8 %12, ptr %19, align 1, !tbaa !6
+  %20 = getelementptr inbounds i8, ptr %16, i32 4
+  br label %40
+
+21:                                               ; preds = %3
+  %22 = shl i32 %5, 2
+  %23 = add i32 %22, 4
+  %24 = tail call ptr @malloc(i32 noundef %23) #10
+  store i8 %6, ptr %24, align 1, !tbaa !6
+  %25 = getelementptr inbounds i8, ptr %24, i32 1
+  store i8 %8, ptr %25, align 1, !tbaa !6
+  %26 = getelementptr inbounds i8, ptr %24, i32 2
+  store i8 %10, ptr %26, align 1, !tbaa !6
+  %27 = getelementptr inbounds i8, ptr %24, i32 3
+  store i8 %12, ptr %27, align 1, !tbaa !6
+  %28 = getelementptr inbounds i8, ptr %24, i32 4
+  %29 = icmp sgt i32 %5, 0
+  br i1 %29, label %30, label %40
+
+30:                                               ; preds = %21
+  %31 = add nsw i32 %0, -1
+  %32 = getelementptr inbounds i32, ptr %2, i32 1
+  br label %33
+
+33:                                               ; preds = %30, %33
+  %34 = phi i32 [ 0, %30 ], [ %37, %33 ]
+  %35 = tail call ptr @.builtin.RecursiveAllocateArray(i32 noundef %31, i32 noundef %1, ptr noundef nonnull %32) #12
+  %36 = getelementptr inbounds ptr, ptr %28, i32 %34
+  store ptr %35, ptr %36, align 4, !tbaa !16
+  %37 = add nuw nsw i32 %34, 1
+  %38 = load i32, ptr %2, align 4, !tbaa !12
+  %39 = icmp slt i32 %37, %38
+  br i1 %39, label %33, label %40, !llvm.loop !18
+
+40:                                               ; preds = %33, %21, %13
+  %41 = phi ptr [ %20, %13 ], [ %28, %21 ], [ %28, %33 ]
+  ret ptr %41
+}
+
+attributes #0 = { nofree norecurse nosync nounwind memory(argmem: read) "no-builtin-memcpy" "no-builtin-printf" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="generic-rv32" "target-features"="+32bit,+a,+c,+m,+relax,-d,-e,-experimental-zacas,-experimental-zcmop,-experimental-zfbfmin,-experimental-zicfilp,-experimental-zicfiss,-experimental-zimop,-experimental-ztso,-experimental-zvfbfmin,-experimental-zvfbfwma,-f,-h,-smaia,-smepmp,-ssaia,-svinval,-svnapot,-svpbmt,-v,-xcvalu,-xcvbi,-xcvbitmanip,-xcvelw,-xcvmac,-xcvmem,-xcvsimd,-xsfvcp,-xsfvfnrclipxfqf,-xsfvfwmaccqqq,-xsfvqmaccdod,-xsfvqmaccqoq,-xtheadba,-xtheadbb,-xtheadbs,-xtheadcmo,-xtheadcondmov,-xtheadfmemidx,-xtheadmac,-xtheadmemidx,-xtheadmempair,-xtheadsync,-xtheadvdot,-xventanacondops,-za128rs,-za64rs,-zawrs,-zba,-zbb,-zbc,-zbkb,-zbkc,-zbkx,-zbs,-zca,-zcb,-zcd,-zce,-zcf,-zcmp,-zcmt,-zdinx,-zfa,-zfh,-zfhmin,-zfinx,-zhinx,-zhinxmin,-zic64b,-zicbom,-zicbop,-zicboz,-ziccamoa,-ziccif,-zicclsm,-ziccrse,-zicntr,-zicond,-zicsr,-zifencei,-zihintntl,-zihintpause,-zihpm,-zk,-zkn,-zknd,-zkne,-zknh,-zkr,-zks,-zksed,-zksh,-zkt,-zmmul,-zvbb,-zvbc,-zve32f,-zve32x,-zve64d,-zve64f,-zve64x,-zvfh,-zvfhmin,-zvkb,-zvkg,-zvkn,-zvknc,-zvkned,-zvkng,-zvknha,-zvknhb,-zvks,-zvksc,-zvksed,-zvksg,-zvksh,-zvkt,-zvl1024b,-zvl128b,-zvl16384b,-zvl2048b,-zvl256b,-zvl32768b,-zvl32b,-zvl4096b,-zvl512b,-zvl64b,-zvl65536b,-zvl8192b" }
+attributes #1 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
+attributes #2 = { nofree nounwind memory(write, argmem: read, inaccessiblemem: readwrite) "no-builtin-memcpy" "no-builtin-printf" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="generic-rv32" "target-features"="+32bit,+a,+c,+m,+relax,-d,-e,-experimental-zacas,-experimental-zcmop,-experimental-zfbfmin,-experimental-zicfilp,-experimental-zicfiss,-experimental-zimop,-experimental-ztso,-experimental-zvfbfmin,-experimental-zvfbfwma,-f,-h,-smaia,-smepmp,-ssaia,-svinval,-svnapot,-svpbmt,-v,-xcvalu,-xcvbi,-xcvbitmanip,-xcvelw,-xcvmac,-xcvmem,-xcvsimd,-xsfvcp,-xsfvfnrclipxfqf,-xsfvfwmaccqqq,-xsfvqmaccdod,-xsfvqmaccqoq,-xtheadba,-xtheadbb,-xtheadbs,-xtheadcmo,-xtheadcondmov,-xtheadfmemidx,-xtheadmac,-xtheadmemidx,-xtheadmempair,-xtheadsync,-xtheadvdot,-xventanacondops,-za128rs,-za64rs,-zawrs,-zba,-zbb,-zbc,-zbkb,-zbkc,-zbkx,-zbs,-zca,-zcb,-zcd,-zce,-zcf,-zcmp,-zcmt,-zdinx,-zfa,-zfh,-zfhmin,-zfinx,-zhinx,-zhinxmin,-zic64b,-zicbom,-zicbop,-zicboz,-ziccamoa,-ziccif,-zicclsm,-ziccrse,-zicntr,-zicond,-zicsr,-zifencei,-zihintntl,-zihintpause,-zihpm,-zk,-zkn,-zknd,-zkne,-zknh,-zkr,-zks,-zksed,-zksh,-zkt,-zmmul,-zvbb,-zvbc,-zve32f,-zve32x,-zve64d,-zve64f,-zve64x,-zvfh,-zvfhmin,-zvkb,-zvkg,-zvkn,-zvknc,-zvkned,-zvkng,-zvknha,-zvknhb,-zvks,-zvksc,-zvksed,-zvksg,-zvksh,-zvkt,-zvl1024b,-zvl128b,-zvl16384b,-zvl2048b,-zvl256b,-zvl32768b,-zvl32b,-zvl4096b,-zvl512b,-zvl64b,-zvl65536b,-zvl8192b" }
+attributes #3 = { mustprogress nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite) "alloc-family"="malloc" "no-builtin-memcpy" "no-builtin-printf" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="generic-rv32" "target-features"="+32bit,+a,+c,+m,+relax,-d,-e,-experimental-zacas,-experimental-zcmop,-experimental-zfbfmin,-experimental-zicfilp,-experimental-zicfiss,-experimental-zimop,-experimental-ztso,-experimental-zvfbfmin,-experimental-zvfbfwma,-f,-h,-smaia,-smepmp,-ssaia,-svinval,-svnapot,-svpbmt,-v,-xcvalu,-xcvbi,-xcvbitmanip,-xcvelw,-xcvmac,-xcvmem,-xcvsimd,-xsfvcp,-xsfvfnrclipxfqf,-xsfvfwmaccqqq,-xsfvqmaccdod,-xsfvqmaccqoq,-xtheadba,-xtheadbb,-xtheadbs,-xtheadcmo,-xtheadcondmov,-xtheadfmemidx,-xtheadmac,-xtheadmemidx,-xtheadmempair,-xtheadsync,-xtheadvdot,-xventanacondops,-za128rs,-za64rs,-zawrs,-zba,-zbb,-zbc,-zbkb,-zbkc,-zbkx,-zbs,-zca,-zcb,-zcd,-zce,-zcf,-zcmp,-zcmt,-zdinx,-zfa,-zfh,-zfhmin,-zfinx,-zhinx,-zhinxmin,-zic64b,-zicbom,-zicbop,-zicboz,-ziccamoa,-ziccif,-zicclsm,-ziccrse,-zicntr,-zicond,-zicsr,-zifencei,-zihintntl,-zihintpause,-zihpm,-zk,-zkn,-zknd,-zkne,-zknh,-zkr,-zks,-zksed,-zksh,-zkt,-zmmul,-zvbb,-zvbc,-zve32f,-zve32x,-zve64d,-zve64f,-zve64x,-zvfh,-zvfhmin,-zvkb,-zvkg,-zvkn,-zvknc,-zvkned,-zvkng,-zvknha,-zvknhb,-zvks,-zvksc,-zvksed,-zvksg,-zvksh,-zvkt,-zvl1024b,-zvl128b,-zvl16384b,-zvl2048b,-zvl256b,-zvl32768b,-zvl32b,-zvl4096b,-zvl512b,-zvl64b,-zvl65536b,-zvl8192b" }
+attributes #4 = { nofree nounwind "no-builtin-memcpy" "no-builtin-printf" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="generic-rv32" "target-features"="+32bit,+a,+c,+m,+relax,-d,-e,-experimental-zacas,-experimental-zcmop,-experimental-zfbfmin,-experimental-zicfilp,-experimental-zicfiss,-experimental-zimop,-experimental-ztso,-experimental-zvfbfmin,-experimental-zvfbfwma,-f,-h,-smaia,-smepmp,-ssaia,-svinval,-svnapot,-svpbmt,-v,-xcvalu,-xcvbi,-xcvbitmanip,-xcvelw,-xcvmac,-xcvmem,-xcvsimd,-xsfvcp,-xsfvfnrclipxfqf,-xsfvfwmaccqqq,-xsfvqmaccdod,-xsfvqmaccqoq,-xtheadba,-xtheadbb,-xtheadbs,-xtheadcmo,-xtheadcondmov,-xtheadfmemidx,-xtheadmac,-xtheadmemidx,-xtheadmempair,-xtheadsync,-xtheadvdot,-xventanacondops,-za128rs,-za64rs,-zawrs,-zba,-zbb,-zbc,-zbkb,-zbkc,-zbkx,-zbs,-zca,-zcb,-zcd,-zce,-zcf,-zcmp,-zcmt,-zdinx,-zfa,-zfh,-zfhmin,-zfinx,-zhinx,-zhinxmin,-zic64b,-zicbom,-zicbop,-zicboz,-ziccamoa,-ziccif,-zicclsm,-ziccrse,-zicntr,-zicond,-zicsr,-zifencei,-zihintntl,-zihintpause,-zihpm,-zk,-zkn,-zknd,-zkne,-zknh,-zkr,-zks,-zksed,-zksh,-zkt,-zmmul,-zvbb,-zvbc,-zve32f,-zve32x,-zve64d,-zve64f,-zve64x,-zvfh,-zvfhmin,-zvkb,-zvkg,-zvkn,-zvknc,-zvkned,-zvkng,-zvknha,-zvknhb,-zvks,-zvksc,-zvksed,-zvksg,-zvksh,-zvkt,-zvl1024b,-zvl128b,-zvl16384b,-zvl2048b,-zvl256b,-zvl32768b,-zvl32b,-zvl4096b,-zvl512b,-zvl64b,-zvl65536b,-zvl8192b" }
+attributes #5 = { mustprogress nofree norecurse nosync nounwind willreturn memory(argmem: read) "no-builtin-memcpy" "no-builtin-printf" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="generic-rv32" "target-features"="+32bit,+a,+c,+m,+relax,-d,-e,-experimental-zacas,-experimental-zcmop,-experimental-zfbfmin,-experimental-zicfilp,-experimental-zicfiss,-experimental-zimop,-experimental-ztso,-experimental-zvfbfmin,-experimental-zvfbfwma,-f,-h,-smaia,-smepmp,-ssaia,-svinval,-svnapot,-svpbmt,-v,-xcvalu,-xcvbi,-xcvbitmanip,-xcvelw,-xcvmac,-xcvmem,-xcvsimd,-xsfvcp,-xsfvfnrclipxfqf,-xsfvfwmaccqqq,-xsfvqmaccdod,-xsfvqmaccqoq,-xtheadba,-xtheadbb,-xtheadbs,-xtheadcmo,-xtheadcondmov,-xtheadfmemidx,-xtheadmac,-xtheadmemidx,-xtheadmempair,-xtheadsync,-xtheadvdot,-xventanacondops,-za128rs,-za64rs,-zawrs,-zba,-zbb,-zbc,-zbkb,-zbkc,-zbkx,-zbs,-zca,-zcb,-zcd,-zce,-zcf,-zcmp,-zcmt,-zdinx,-zfa,-zfh,-zfhmin,-zfinx,-zhinx,-zhinxmin,-zic64b,-zicbom,-zicbop,-zicboz,-ziccamoa,-ziccif,-zicclsm,-ziccrse,-zicntr,-zicond,-zicsr,-zifencei,-zihintntl,-zihintpause,-zihpm,-zk,-zkn,-zknd,-zkne,-zknh,-zkr,-zks,-zksed,-zksh,-zkt,-zmmul,-zvbb,-zvbc,-zve32f,-zve32x,-zve64d,-zve64f,-zve64x,-zvfh,-zvfhmin,-zvkb,-zvkg,-zvkn,-zvknc,-zvkned,-zvkng,-zvknha,-zvknhb,-zvks,-zvksc,-zvksed,-zvksg,-zvksh,-zvkt,-zvl1024b,-zvl128b,-zvl16384b,-zvl2048b,-zvl256b,-zvl32768b,-zvl32b,-zvl4096b,-zvl512b,-zvl64b,-zvl65536b,-zvl8192b" }
+attributes #6 = { nounwind "no-builtin-memcpy" "no-builtin-printf" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="generic-rv32" "target-features"="+32bit,+a,+c,+m,+relax,-d,-e,-experimental-zacas,-experimental-zcmop,-experimental-zfbfmin,-experimental-zicfilp,-experimental-zicfiss,-experimental-zimop,-experimental-ztso,-experimental-zvfbfmin,-experimental-zvfbfwma,-f,-h,-smaia,-smepmp,-ssaia,-svinval,-svnapot,-svpbmt,-v,-xcvalu,-xcvbi,-xcvbitmanip,-xcvelw,-xcvmac,-xcvmem,-xcvsimd,-xsfvcp,-xsfvfnrclipxfqf,-xsfvfwmaccqqq,-xsfvqmaccdod,-xsfvqmaccqoq,-xtheadba,-xtheadbb,-xtheadbs,-xtheadcmo,-xtheadcondmov,-xtheadfmemidx,-xtheadmac,-xtheadmemidx,-xtheadmempair,-xtheadsync,-xtheadvdot,-xventanacondops,-za128rs,-za64rs,-zawrs,-zba,-zbb,-zbc,-zbkb,-zbkc,-zbkx,-zbs,-zca,-zcb,-zcd,-zce,-zcf,-zcmp,-zcmt,-zdinx,-zfa,-zfh,-zfhmin,-zfinx,-zhinx,-zhinxmin,-zic64b,-zicbom,-zicbop,-zicboz,-ziccamoa,-ziccif,-zicclsm,-ziccrse,-zicntr,-zicond,-zicsr,-zifencei,-zihintntl,-zihintpause,-zihpm,-zk,-zkn,-zknd,-zkne,-zknh,-zkr,-zks,-zksed,-zksh,-zkt,-zmmul,-zvbb,-zvbc,-zve32f,-zve32x,-zve64d,-zve64f,-zve64x,-zvfh,-zvfhmin,-zvkb,-zvkg,-zvkn,-zvknc,-zvkned,-zvkng,-zvknha,-zvknhb,-zvks,-zvksc,-zvksed,-zvksg,-zvksh,-zvkt,-zvl1024b,-zvl128b,-zvl16384b,-zvl2048b,-zvl256b,-zvl32768b,-zvl32b,-zvl4096b,-zvl512b,-zvl64b,-zvl65536b,-zvl8192b" }
+attributes #7 = { "no-builtin-memcpy" "no-builtin-printf" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="generic-rv32" "target-features"="+32bit,+a,+c,+m,+relax,-d,-e,-experimental-zacas,-experimental-zcmop,-experimental-zfbfmin,-experimental-zicfilp,-experimental-zicfiss,-experimental-zimop,-experimental-ztso,-experimental-zvfbfmin,-experimental-zvfbfwma,-f,-h,-smaia,-smepmp,-ssaia,-svinval,-svnapot,-svpbmt,-v,-xcvalu,-xcvbi,-xcvbitmanip,-xcvelw,-xcvmac,-xcvmem,-xcvsimd,-xsfvcp,-xsfvfnrclipxfqf,-xsfvfwmaccqqq,-xsfvqmaccdod,-xsfvqmaccqoq,-xtheadba,-xtheadbb,-xtheadbs,-xtheadcmo,-xtheadcondmov,-xtheadfmemidx,-xtheadmac,-xtheadmemidx,-xtheadmempair,-xtheadsync,-xtheadvdot,-xventanacondops,-za128rs,-za64rs,-zawrs,-zba,-zbb,-zbc,-zbkb,-zbkc,-zbkx,-zbs,-zca,-zcb,-zcd,-zce,-zcf,-zcmp,-zcmt,-zdinx,-zfa,-zfh,-zfhmin,-zfinx,-zhinx,-zhinxmin,-zic64b,-zicbom,-zicbop,-zicboz,-ziccamoa,-ziccif,-zicclsm,-ziccrse,-zicntr,-zicond,-zicsr,-zifencei,-zihintntl,-zihintpause,-zihpm,-zk,-zkn,-zknd,-zkne,-zknh,-zkr,-zks,-zksed,-zksh,-zkt,-zmmul,-zvbb,-zvbc,-zve32f,-zve32x,-zve64d,-zve64f,-zve64x,-zvfh,-zvfhmin,-zvkb,-zvkg,-zvkn,-zvknc,-zvkned,-zvkng,-zvknha,-zvknhb,-zvks,-zvksc,-zvksed,-zvksg,-zvksh,-zvkt,-zvl1024b,-zvl128b,-zvl16384b,-zvl2048b,-zvl256b,-zvl32768b,-zvl32b,-zvl4096b,-zvl512b,-zvl64b,-zvl65536b,-zvl8192b" }
+attributes #8 = { mustprogress nounwind willreturn allockind("free") memory(argmem: readwrite, inaccessiblemem: readwrite) "alloc-family"="malloc" "no-builtin-memcpy" "no-builtin-printf" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="generic-rv32" "target-features"="+32bit,+a,+c,+m,+relax,-d,-e,-experimental-zacas,-experimental-zcmop,-experimental-zfbfmin,-experimental-zicfilp,-experimental-zicfiss,-experimental-zimop,-experimental-ztso,-experimental-zvfbfmin,-experimental-zvfbfwma,-f,-h,-smaia,-smepmp,-ssaia,-svinval,-svnapot,-svpbmt,-v,-xcvalu,-xcvbi,-xcvbitmanip,-xcvelw,-xcvmac,-xcvmem,-xcvsimd,-xsfvcp,-xsfvfnrclipxfqf,-xsfvfwmaccqqq,-xsfvqmaccdod,-xsfvqmaccqoq,-xtheadba,-xtheadbb,-xtheadbs,-xtheadcmo,-xtheadcondmov,-xtheadfmemidx,-xtheadmac,-xtheadmemidx,-xtheadmempair,-xtheadsync,-xtheadvdot,-xventanacondops,-za128rs,-za64rs,-zawrs,-zba,-zbb,-zbc,-zbkb,-zbkc,-zbkx,-zbs,-zca,-zcb,-zcd,-zce,-zcf,-zcmp,-zcmt,-zdinx,-zfa,-zfh,-zfhmin,-zfinx,-zhinx,-zhinxmin,-zic64b,-zicbom,-zicbop,-zicboz,-ziccamoa,-ziccif,-zicclsm,-ziccrse,-zicntr,-zicond,-zicsr,-zifencei,-zihintntl,-zihintpause,-zihpm,-zk,-zkn,-zknd,-zkne,-zknh,-zkr,-zks,-zksed,-zksh,-zkt,-zmmul,-zvbb,-zvbc,-zve32f,-zve32x,-zve64d,-zve64f,-zve64x,-zvfh,-zvfhmin,-zvkb,-zvkg,-zvkn,-zvknc,-zvkned,-zvkng,-zvknha,-zvknhb,-zvks,-zvksc,-zvksed,-zvksg,-zvksh,-zvkt,-zvl1024b,-zvl128b,-zvl16384b,-zvl2048b,-zvl256b,-zvl32768b,-zvl32b,-zvl4096b,-zvl512b,-zvl64b,-zvl65536b,-zvl8192b" }
+attributes #9 = { mustprogress nofree nounwind willreturn memory(inaccessiblemem: readwrite) "no-builtin-memcpy" "no-builtin-printf" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="generic-rv32" "target-features"="+32bit,+a,+c,+m,+relax,-d,-e,-experimental-zacas,-experimental-zcmop,-experimental-zfbfmin,-experimental-zicfilp,-experimental-zicfiss,-experimental-zimop,-experimental-ztso,-experimental-zvfbfmin,-experimental-zvfbfwma,-f,-h,-smaia,-smepmp,-ssaia,-svinval,-svnapot,-svpbmt,-v,-xcvalu,-xcvbi,-xcvbitmanip,-xcvelw,-xcvmac,-xcvmem,-xcvsimd,-xsfvcp,-xsfvfnrclipxfqf,-xsfvfwmaccqqq,-xsfvqmaccdod,-xsfvqmaccqoq,-xtheadba,-xtheadbb,-xtheadbs,-xtheadcmo,-xtheadcondmov,-xtheadfmemidx,-xtheadmac,-xtheadmemidx,-xtheadmempair,-xtheadsync,-xtheadvdot,-xventanacondops,-za128rs,-za64rs,-zawrs,-zba,-zbb,-zbc,-zbkb,-zbkc,-zbkx,-zbs,-zca,-zcb,-zcd,-zce,-zcf,-zcmp,-zcmt,-zdinx,-zfa,-zfh,-zfhmin,-zfinx,-zhinx,-zhinxmin,-zic64b,-zicbom,-zicbop,-zicboz,-ziccamoa,-ziccif,-zicclsm,-ziccrse,-zicntr,-zicond,-zicsr,-zifencei,-zihintntl,-zihintpause,-zihpm,-zk,-zkn,-zknd,-zkne,-zknh,-zkr,-zks,-zksed,-zksh,-zkt,-zmmul,-zvbb,-zvbc,-zve32f,-zve32x,-zve64d,-zve64f,-zve64x,-zvfh,-zvfhmin,-zvkb,-zvkg,-zvkn,-zvknc,-zvkned,-zvkng,-zvknha,-zvknhb,-zvks,-zvksc,-zvksed,-zvksg,-zvksh,-zvkt,-zvl1024b,-zvl128b,-zvl16384b,-zvl2048b,-zvl256b,-zvl32768b,-zvl32b,-zvl4096b,-zvl512b,-zvl64b,-zvl65536b,-zvl8192b" }
+attributes #10 = { allocsize(0) "no-builtin-memcpy" "no-builtin-printf" }
+attributes #11 = { nounwind }
+attributes #12 = { "no-builtin-memcpy" "no-builtin-printf" }
+attributes #13 = { nobuiltin nounwind "no-builtin-memcpy" "no-builtin-printf" }
+
+!llvm.module.flags = !{!0, !1, !2, !4}
+!llvm.ident = !{!5}
+
+!0 = !{i32 1, !"wchar_size", i32 4}
+!1 = !{i32 1, !"target-abi", !"ilp32"}
+!2 = !{i32 6, !"riscv-isa", !3}
+!3 = !{!"rv32i2p1_m2p0_a2p1_c2p0"}
+!4 = !{i32 8, !"SmallDataLimit", i32 8}
+!5 = !{!"Ubuntu clang version 18.1.8 (++20240731024944+3b5b5c1ec4a3-1~exp1~20240731145000.144)"}
+!6 = !{!7, !7, i64 0}
+!7 = !{!"omnipotent char", !8, i64 0}
+!8 = !{!"Simple C/C++ TBAA"}
+!9 = distinct !{!9, !10}
+!10 = !{!"llvm.loop.mustprogress"}
+!11 = distinct !{!11, !10}
+!12 = !{!13, !13, i64 0}
+!13 = !{!"int", !7, i64 0}
+!14 = distinct !{!14, !10}
+!15 = distinct !{!15, !10}
+!16 = !{!17, !17, i64 0}
+!17 = !{!"any pointer", !7, i64 0}
+!18 = distinct !{!18, !10}
diff --git a/src/IR/builtin.s b/src/IR/builtin.s
new file mode 100644
index 0000000..2324839
--- /dev/null
+++ b/src/IR/builtin.s
@@ -0,0 +1,464 @@
+	.text
+	.attribute	4, 16
+	.attribute	5, "rv32i2p1_m2p0_a2p1_c2p0"
+	.file	"builtin.c"
+	.option	push
+	.option	arch, +a, +c, +m
+	.globl	string.length                   # -- Begin function string.length
+	.p2align	1
+	.type	string.length,@function
+string.length:                          # @string.length
+# %bb.0:
+	li	a1, 0
+.LBB0_1:                                # =>This Inner Loop Header: Depth=1
+	add	a2, a0, a1
+	lbu	a2, 0(a2)
+	addi	a1, a1, 1
+	bnez	a2, .LBB0_1
+# %bb.2:
+	addi	a0, a1, -1
+	ret
+.Lfunc_end0:
+	.size	string.length, .Lfunc_end0-string.length
+                                        # -- End function
+	.option	pop
+	.option	push
+	.option	arch, +a, +c, +m
+	.globl	string.substring                # -- Begin function string.substring
+	.p2align	1
+	.type	string.substring,@function
+string.substring:                       # @string.substring
+# %bb.0:
+	addi	sp, sp, -16
+	sw	ra, 12(sp)                      # 4-byte Folded Spill
+	sw	s0, 8(sp)                       # 4-byte Folded Spill
+	sw	s1, 4(sp)                       # 4-byte Folded Spill
+	sw	s2, 0(sp)                       # 4-byte Folded Spill
+	mv	s0, a1
+	mv	s2, a0
+	sub	s1, a2, a1
+	addi	a0, s1, 1
+	call	malloc
+	add	a1, a0, s1
+	blez	s1, .LBB1_3
+# %bb.1:                                # %.preheader
+	add	s0, s0, s2
+	mv	a2, a0
+.LBB1_2:                                # =>This Inner Loop Header: Depth=1
+	lbu	a3, 0(s0)
+	sb	a3, 0(a2)
+	addi	a2, a2, 1
+	addi	s0, s0, 1
+	bne	a2, a1, .LBB1_2
+.LBB1_3:
+	sb	zero, 0(a1)
+	lw	ra, 12(sp)                      # 4-byte Folded Reload
+	lw	s0, 8(sp)                       # 4-byte Folded Reload
+	lw	s1, 4(sp)                       # 4-byte Folded Reload
+	lw	s2, 0(sp)                       # 4-byte Folded Reload
+	addi	sp, sp, 16
+	ret
+.Lfunc_end1:
+	.size	string.substring, .Lfunc_end1-string.substring
+                                        # -- End function
+	.option	pop
+	.option	push
+	.option	arch, +a, +c, +m
+	.globl	string.parseInt                 # -- Begin function string.parseInt
+	.p2align	1
+	.type	string.parseInt,@function
+string.parseInt:                        # @string.parseInt
+# %bb.0:
+	addi	sp, sp, -16
+	sw	ra, 12(sp)                      # 4-byte Folded Spill
+	lui	a1, %hi(.L.str)
+	addi	a1, a1, %lo(.L.str)
+	addi	a2, sp, 8
+	call	sscanf
+	lw	a0, 8(sp)
+	lw	ra, 12(sp)                      # 4-byte Folded Reload
+	addi	sp, sp, 16
+	ret
+.Lfunc_end2:
+	.size	string.parseInt, .Lfunc_end2-string.parseInt
+                                        # -- End function
+	.option	pop
+	.option	push
+	.option	arch, +a, +c, +m
+	.globl	string.ord                      # -- Begin function string.ord
+	.p2align	1
+	.type	string.ord,@function
+string.ord:                             # @string.ord
+# %bb.0:
+	add	a0, a0, a1
+	lbu	a0, 0(a0)
+	ret
+.Lfunc_end3:
+	.size	string.ord, .Lfunc_end3-string.ord
+                                        # -- End function
+	.option	pop
+	.option	push
+	.option	arch, +a, +c, +m
+	.globl	print                           # -- Begin function print
+	.p2align	1
+	.type	print,@function
+print:                                  # @print
+# %bb.0:
+	lui	a1, %hi(.L.str.1)
+	addi	a1, a1, %lo(.L.str.1)
+	mv	a2, a0
+	mv	a0, a1
+	mv	a1, a2
+	tail	printf
+.Lfunc_end4:
+	.size	print, .Lfunc_end4-print
+                                        # -- End function
+	.option	pop
+	.option	push
+	.option	arch, +a, +c, +m
+	.globl	println                         # -- Begin function println
+	.p2align	1
+	.type	println,@function
+println:                                # @println
+# %bb.0:
+	lui	a1, %hi(.L.str.2)
+	addi	a1, a1, %lo(.L.str.2)
+	mv	a2, a0
+	mv	a0, a1
+	mv	a1, a2
+	tail	printf
+.Lfunc_end5:
+	.size	println, .Lfunc_end5-println
+                                        # -- End function
+	.option	pop
+	.option	push
+	.option	arch, +a, +c, +m
+	.globl	printInt                        # -- Begin function printInt
+	.p2align	1
+	.type	printInt,@function
+printInt:                               # @printInt
+# %bb.0:
+	lui	a1, %hi(.L.str)
+	addi	a1, a1, %lo(.L.str)
+	mv	a2, a0
+	mv	a0, a1
+	mv	a1, a2
+	tail	printf
+.Lfunc_end6:
+	.size	printInt, .Lfunc_end6-printInt
+                                        # -- End function
+	.option	pop
+	.option	push
+	.option	arch, +a, +c, +m
+	.globl	printlnInt                      # -- Begin function printlnInt
+	.p2align	1
+	.type	printlnInt,@function
+printlnInt:                             # @printlnInt
+# %bb.0:
+	lui	a1, %hi(.L.str.3)
+	addi	a1, a1, %lo(.L.str.3)
+	mv	a2, a0
+	mv	a0, a1
+	mv	a1, a2
+	tail	printf
+.Lfunc_end7:
+	.size	printlnInt, .Lfunc_end7-printlnInt
+                                        # -- End function
+	.option	pop
+	.option	push
+	.option	arch, +a, +c, +m
+	.globl	toString                        # -- Begin function toString
+	.p2align	1
+	.type	toString,@function
+toString:                               # @toString
+# %bb.0:
+	addi	sp, sp, -16
+	sw	ra, 12(sp)                      # 4-byte Folded Spill
+	sw	s0, 8(sp)                       # 4-byte Folded Spill
+	sw	s1, 4(sp)                       # 4-byte Folded Spill
+	mv	s0, a0
+	li	a0, 15
+	call	malloc
+	mv	s1, a0
+	lui	a0, %hi(.L.str)
+	addi	a1, a0, %lo(.L.str)
+	mv	a0, s1
+	mv	a2, s0
+	call	sprintf
+	mv	a0, s1
+	lw	ra, 12(sp)                      # 4-byte Folded Reload
+	lw	s0, 8(sp)                       # 4-byte Folded Reload
+	lw	s1, 4(sp)                       # 4-byte Folded Reload
+	addi	sp, sp, 16
+	ret
+.Lfunc_end8:
+	.size	toString, .Lfunc_end8-toString
+                                        # -- End function
+	.option	pop
+	.option	push
+	.option	arch, +a, +c, +m
+	.globl	getString                       # -- Begin function getString
+	.p2align	1
+	.type	getString,@function
+getString:                              # @getString
+# %bb.0:
+	addi	sp, sp, -48
+	sw	ra, 44(sp)                      # 4-byte Folded Spill
+	sw	s0, 40(sp)                      # 4-byte Folded Spill
+	sw	s1, 36(sp)                      # 4-byte Folded Spill
+	sw	s2, 32(sp)                      # 4-byte Folded Spill
+	sw	s3, 28(sp)                      # 4-byte Folded Spill
+	sw	s4, 24(sp)                      # 4-byte Folded Spill
+	sw	s5, 20(sp)                      # 4-byte Folded Spill
+	sw	s6, 16(sp)                      # 4-byte Folded Spill
+	sw	s7, 12(sp)                      # 4-byte Folded Spill
+	sw	s8, 8(sp)                       # 4-byte Folded Spill
+	li	a0, 11
+	call	malloc
+	mv	s8, a0
+	lui	a0, %hi(.L.str.4)
+	addi	s2, a0, %lo(.L.str.4)
+	addi	a1, sp, 7
+	mv	a0, s2
+	call	scanf
+	li	s3, 1
+	bne	a0, s3, .LBB9_11
+# %bb.1:                                # %.preheader1
+	li	s1, 0
+	li	s4, 10
+	li	s5, 13
+	mv	s6, s8
+	li	s7, 10
+	j	.LBB9_4
+.LBB9_2:                                #   in Loop: Header=BB9_4 Depth=1
+	mv	s8, s6
+.LBB9_3:                                #   in Loop: Header=BB9_4 Depth=1
+	addi	s0, s1, 1
+	add	s1, s1, s8
+	sb	a0, 0(s1)
+	addi	a1, sp, 7
+	mv	a0, s2
+	call	scanf
+	mv	s1, s0
+	bne	a0, s3, .LBB9_13
+.LBB9_4:                                # =>This Loop Header: Depth=1
+                                        #     Child Loop BB9_9 Depth 2
+	lbu	a0, 7(sp)
+	beq	a0, s4, .LBB9_12
+# %bb.5:                                #   in Loop: Header=BB9_4 Depth=1
+	beq	a0, s5, .LBB9_12
+# %bb.6:                                #   in Loop: Header=BB9_4 Depth=1
+	bne	s1, s7, .LBB9_2
+# %bb.7:                                #   in Loop: Header=BB9_4 Depth=1
+	slli	s7, s1, 1
+	addi	a0, s7, 1
+	call	malloc
+	mv	s8, a0
+	beqz	s1, .LBB9_10
+# %bb.8:                                # %.preheader
+                                        #   in Loop: Header=BB9_4 Depth=1
+	add	a0, s8, s1
+	mv	a1, s6
+	mv	a2, s8
+.LBB9_9:                                #   Parent Loop BB9_4 Depth=1
+                                        # =>  This Inner Loop Header: Depth=2
+	lbu	a3, 0(a1)
+	sb	a3, 0(a2)
+	addi	a2, a2, 1
+	addi	a1, a1, 1
+	bne	a2, a0, .LBB9_9
+.LBB9_10:                               #   in Loop: Header=BB9_4 Depth=1
+	mv	a0, s6
+	call	free
+	lbu	a0, 7(sp)
+	mv	s6, s8
+	j	.LBB9_3
+.LBB9_11:
+	li	s0, 0
+	j	.LBB9_13
+.LBB9_12:
+	mv	s0, s1
+	mv	s8, s6
+.LBB9_13:
+	add	s0, s0, s8
+	sb	zero, 0(s0)
+	mv	a0, s8
+	lw	ra, 44(sp)                      # 4-byte Folded Reload
+	lw	s0, 40(sp)                      # 4-byte Folded Reload
+	lw	s1, 36(sp)                      # 4-byte Folded Reload
+	lw	s2, 32(sp)                      # 4-byte Folded Reload
+	lw	s3, 28(sp)                      # 4-byte Folded Reload
+	lw	s4, 24(sp)                      # 4-byte Folded Reload
+	lw	s5, 20(sp)                      # 4-byte Folded Reload
+	lw	s6, 16(sp)                      # 4-byte Folded Reload
+	lw	s7, 12(sp)                      # 4-byte Folded Reload
+	lw	s8, 8(sp)                       # 4-byte Folded Reload
+	addi	sp, sp, 48
+	ret
+.Lfunc_end9:
+	.size	getString, .Lfunc_end9-getString
+                                        # -- End function
+	.option	pop
+	.option	push
+	.option	arch, +a, +c, +m
+	.globl	getInt                          # -- Begin function getInt
+	.p2align	1
+	.type	getInt,@function
+getInt:                                 # @getInt
+# %bb.0:
+	addi	sp, sp, -16
+	sw	ra, 12(sp)                      # 4-byte Folded Spill
+	lui	a0, %hi(.L.str)
+	addi	a0, a0, %lo(.L.str)
+	addi	a1, sp, 8
+	call	scanf
+	lw	a0, 8(sp)
+	lw	ra, 12(sp)                      # 4-byte Folded Reload
+	addi	sp, sp, 16
+	ret
+.Lfunc_end10:
+	.size	getInt, .Lfunc_end10-getInt
+                                        # -- End function
+	.option	pop
+	.option	push
+	.option	arch, +a, +c, +m
+	.globl	.builtin.AllocateClassBody      # -- Begin function .builtin.AllocateClassBody
+	.p2align	1
+	.type	.builtin.AllocateClassBody,@function
+.builtin.AllocateClassBody:             # @.builtin.AllocateClassBody
+# %bb.0:
+	tail	malloc
+.Lfunc_end11:
+	.size	.builtin.AllocateClassBody, .Lfunc_end11-.builtin.AllocateClassBody
+                                        # -- End function
+	.option	pop
+	.option	push
+	.option	arch, +a, +c, +m
+	.globl	.builtin.GetArrayLength         # -- Begin function .builtin.GetArrayLength
+	.p2align	1
+	.type	.builtin.GetArrayLength,@function
+.builtin.GetArrayLength:                # @.builtin.GetArrayLength
+# %bb.0:
+	lbu	a1, -3(a0)
+	lbu	a2, -4(a0)
+	lbu	a3, -2(a0)
+	lbu	a0, -1(a0)
+	slli	a1, a1, 8
+	or	a1, a1, a2
+	slli	a3, a3, 16
+	slli	a0, a0, 24
+	or	a0, a0, a3
+	or	a0, a0, a1
+	ret
+.Lfunc_end12:
+	.size	.builtin.GetArrayLength, .Lfunc_end12-.builtin.GetArrayLength
+                                        # -- End function
+	.option	pop
+	.option	push
+	.option	arch, +a, +c, +m
+	.globl	.builtin.RecursiveAllocateArray # -- Begin function .builtin.RecursiveAllocateArray
+	.p2align	1
+	.type	.builtin.RecursiveAllocateArray,@function
+.builtin.RecursiveAllocateArray:        # @.builtin.RecursiveAllocateArray
+# %bb.0:
+	addi	sp, sp, -48
+	sw	ra, 44(sp)                      # 4-byte Folded Spill
+	sw	s0, 40(sp)                      # 4-byte Folded Spill
+	sw	s1, 36(sp)                      # 4-byte Folded Spill
+	sw	s2, 32(sp)                      # 4-byte Folded Spill
+	sw	s3, 28(sp)                      # 4-byte Folded Spill
+	sw	s4, 24(sp)                      # 4-byte Folded Spill
+	sw	s5, 20(sp)                      # 4-byte Folded Spill
+	sw	s6, 16(sp)                      # 4-byte Folded Spill
+	sw	s7, 12(sp)                      # 4-byte Folded Spill
+	lw	s0, 0(a2)
+	mv	s3, a1
+	mv	s2, a0
+	srli	s5, s0, 8
+	srli	s4, s0, 16
+	li	a0, 1
+	srli	s6, s0, 24
+	bne	s2, a0, .LBB13_2
+# %bb.1:
+	mul	a0, s0, s3
+	addi	a0, a0, 4
+	call	malloc
+	sb	s0, 0(a0)
+	sb	s5, 1(a0)
+	sb	s4, 2(a0)
+	sb	s6, 3(a0)
+	addi	a0, a0, 4
+	j	.LBB13_6
+.LBB13_2:
+	mv	s7, a2
+	slli	a0, s0, 2
+	addi	a0, a0, 4
+	call	malloc
+	sb	s0, 0(a0)
+	sb	s5, 1(a0)
+	sb	s4, 2(a0)
+	sb	s6, 3(a0)
+	addi	a0, a0, 4
+	blez	s0, .LBB13_6
+# %bb.3:
+	li	s1, 0
+	addi	s2, s2, -1
+	addi	s5, s7, 4
+	mv	s4, a0
+	mv	s0, a0
+.LBB13_4:                               # =>This Inner Loop Header: Depth=1
+	mv	a0, s2
+	mv	a1, s3
+	mv	a2, s5
+	call	.builtin.RecursiveAllocateArray
+	lw	a1, 0(s7)
+	sw	a0, 0(s0)
+	addi	s1, s1, 1
+	addi	s0, s0, 4
+	blt	s1, a1, .LBB13_4
+# %bb.5:
+	mv	a0, s4
+.LBB13_6:
+	lw	ra, 44(sp)                      # 4-byte Folded Reload
+	lw	s0, 40(sp)                      # 4-byte Folded Reload
+	lw	s1, 36(sp)                      # 4-byte Folded Reload
+	lw	s2, 32(sp)                      # 4-byte Folded Reload
+	lw	s3, 28(sp)                      # 4-byte Folded Reload
+	lw	s4, 24(sp)                      # 4-byte Folded Reload
+	lw	s5, 20(sp)                      # 4-byte Folded Reload
+	lw	s6, 16(sp)                      # 4-byte Folded Reload
+	lw	s7, 12(sp)                      # 4-byte Folded Reload
+	addi	sp, sp, 48
+	ret
+.Lfunc_end13:
+	.size	.builtin.RecursiveAllocateArray, .Lfunc_end13-.builtin.RecursiveAllocateArray
+                                        # -- End function
+	.option	pop
+	.type	.L.str,@object                  # @.str
+	.section	.rodata.str1.1,"aMS",@progbits,1
+.L.str:
+	.asciz	"%d"
+	.size	.L.str, 3
+
+	.type	.L.str.1,@object                # @.str.1
+.L.str.1:
+	.asciz	"%s"
+	.size	.L.str.1, 3
+
+	.type	.L.str.2,@object                # @.str.2
+.L.str.2:
+	.asciz	"%s\n"
+	.size	.L.str.2, 4
+
+	.type	.L.str.3,@object                # @.str.3
+.L.str.3:
+	.asciz	"%d\n"
+	.size	.L.str.3, 4
+
+	.type	.L.str.4,@object                # @.str.4
+.L.str.4:
+	.asciz	"%c"
+	.size	.L.str.4, 3
+
+	.ident	"Ubuntu clang version 18.1.8 (++20240731024944+3b5b5c1ec4a3-1~exp1~20240731145000.144)"
+	.section	".note.GNU-stack","",@progbits
diff --git a/src/ast/semanticvisitor.cpp b/src/ast/semanticvisitor.cpp
index eb255f3..53b2e0b 100644
--- a/src/ast/semanticvisitor.cpp
+++ b/src/ast/semanticvisitor.cpp
@@ -1,6 +1,6 @@
 #include <cstddef>
 #include <functional>
-#include "astnode_visitor.h"
+#include "semantic_visitor.h"
 #include "scope.hpp"
 #include "tools.h"
 
@@ -444,6 +444,7 @@ void ASTSemanticCheckVisitor::ActuralVisit(AssignExpr_ASTNode *node) {
   if (node->dest->expr_type_info != node->src->expr_type_info) {
     throw SemanticError("Type Mismatch", 1);
   }
+  node->expr_type_info = node->src->expr_type_info;
 }
 
 void ASTSemanticCheckVisitor::ActuralVisit(ThisExpr_ASTNode *node) {
diff --git a/src/main.cpp b/src/main.cpp
index 0694b8b..4cd13d6 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,6 +1,7 @@
 #include <argparse/argparse.hpp>
 #include <fstream>
 #include <iostream>
+#include "IR/IR.h"
 #include "semantic/semantic.h"
 
 int main(int argc, char **argv) {
@@ -24,6 +25,7 @@ int main(int argc, char **argv) {
   std::shared_ptr<Program_ASTNode> ast;
   try {
     SemanticCheck(fin, ast);
+    auto IR = BuildIR(ast);
   } catch (const SemanticError &err) {
     std::cout << err.what() << std::endl;
     return err.GetErrorCode();