diff --git a/include/mc_inst.h b/include/mc_inst.h
index 8dce4aa..b1b2b03 100644
--- a/include/mc_inst.h
+++ b/include/mc_inst.h
@@ -182,6 +182,8 @@ public:
 
 class MBasicBlock {
 public:
+  int id;
+  std::list<sptr(MBasicBlock)>::iterator itr;
   sptr(BasicBlock) ir_bb;
   sptr(MFunction) parent_func;
   std::list<sptr(MInst)> inst_list;
diff --git a/src/mc_asmgen.cpp b/src/mc_asmgen.cpp
index 8387a69..1c7b370 100644
--- a/src/mc_asmgen.cpp
+++ b/src/mc_asmgen.cpp
@@ -3,13 +3,79 @@
 
 namespace CompSysY {
 
+using std::endl;
+
+static void bb_debug(std::ostream &ostr, sptr(MBasicBlock) bb) {
+  ostr << "pred:";
+  for (auto item : bb->pred_list) {
+    ostr << "L_BB_" << item->id << ",";
+  }
+  ostr << "\n";
+  ostr << "succ:";
+  for (auto item : bb->succ_list) {
+    ostr << "L_BB_" << item->id << ",";
+  }
+  ostr << "\n";
+  ostr << "livein:";
+  for (auto item : bb->livein) {
+    ostr << item.to_string() << ",";
+  }
+  ostr << "\n";
+  ostr << "liveout:";
+  for (auto item : bb->liveout) {
+    ostr << item.to_string() << ",";
+  }
+  ostr << "\n";
+}
 
 void MCModule::MC2ASM(std::ostream &ostr) {
   // header, specifying align and arch
   ostr << "\t.text\n" << "\t.attribute\t4,\t16\n"
         << "\t.attribute\t5\t\"rv64i2p0_m2p0_f2p0_d2p0\"\n";
-  ostr << "\t.file\t\"" << this->file_name << "\"\n" << std::endl;
-  
+  ostr << "\t.file\t\"" << this->file_name << "\"\n" << endl;
+  for (auto func : this->function_list) {
+    // function header
+    ostr << "\n\n";
+    ostr << ".global\t" << func->ir_func->name << endl;
+    ostr << "\t.type\t" << func->ir_func->name << "\tSTT_FUNC" << endl;
+    ostr << func->ir_func->name << ":" << endl;
+    //TODO entry code
+    for (auto bb : func->bb_list) {
+      ostr << "L_BB_" << bb->id << ":" << endl;
+      ostr << "/*\n";
+      bb_debug(ostr, bb);
+      ostr << "\n*/" << endl;
+      for (auto inst : bb->inst_list) {
+        switch (inst->inst_tag) {
+          case MInstTag::Add: break;
+          case MInstTag::Sub: break;
+          case MInstTag::Mul: break;
+          case MInstTag::Div: break;
+          case MInstTag::Mod: break;
+          case MInstTag::Lt: break;
+          case MInstTag::Le: break;
+          case MInstTag::Ge: break;
+          case MInstTag::Gt: break;
+          case MInstTag::Eq: break;
+          case MInstTag::Ne: break;
+          case MInstTag::And: break;
+          case MInstTag::Or: break;
+          case MInstTag::Lsh: break;
+          case MInstTag::Rsh: break;
+          case MInstTag::Move: break;
+          case MInstTag::Branch: break;
+          case MInstTag::Jmp: break;
+          case MInstTag::Ret: break;
+          case MInstTag::Load: break;
+          case MInstTag::Store: break;
+          case MInstTag::Compare: break;
+          case MInstTag::Call: break;
+          case MInstTag::Globsym: break;
+          case MInstTag::Comment: break;
+        }
+      }
+    }
+  }
 }
 
 }
\ No newline at end of file
diff --git a/src/mc_codegen.cpp b/src/mc_codegen.cpp
index c9f9de0..a6f9be2 100644
--- a/src/mc_codegen.cpp
+++ b/src/mc_codegen.cpp
@@ -93,10 +93,11 @@ static MOperand value2moperand(
 
 void MCModule::IR2MC(const Module &ir_module) {
   // Simply copy globals, since they don't need any translation
+  int bb_id_cnt = 0;
   for (auto glob : ir_module.global_var_list) {
     this->global_list.push_back(glob);
   }
-
+  
   for (auto func : ir_module.function_list) {
     if (func->is_libfunc()) continue;
     auto mc_func = make_shared<MFunction>();
@@ -107,7 +108,8 @@ void MCModule::IR2MC(const Module &ir_module) {
     std::unordered_map<sptr(BasicBlock), sptr(MBasicBlock)> bb_ir2mc;
     for (auto bb : func->bb_list) {
       auto mc_bb = make_shared<MBasicBlock>();
-      mc_func->bb_list.push_back(mc_bb);
+      mc_bb->id = bb_id_cnt ++;
+      mc_bb->itr = mc_func->bb_list.insert(mc_func->bb_list.end(), mc_bb);
       mc_bb->ir_bb       = bb;
       mc_bb->parent_func = mc_func;
       bb_ir2mc.insert({bb, mc_bb});