diff --git a/src/bin/maple b/src/bin/maple
index ed53b9672d2f3eafcd08ee10f70646a1a4e08eaa..3c4417ecf864552484363d2cb4abf0de98045d9e 100755
Binary files a/src/bin/maple and b/src/bin/maple differ
diff --git a/src/bin/mplcg b/src/bin/mplcg
index e5195020daf85b8a2e8f2456625a71feed7d66b3..de252c51c1e310618d3fecf7474cb885cca26b72 100755
Binary files a/src/bin/mplcg and b/src/bin/mplcg differ
diff --git a/src/maple_ir/include/opcodes.h b/src/maple_ir/include/opcodes.h
index fea500ac604b8ba3c1f2b8121250d3e992a825e1..6af2017ca4c6e3f13b5fc944cc66737241285912 100644
--- a/src/maple_ir/include/opcodes.h
+++ b/src/maple_ir/include/opcodes.h
@@ -39,15 +39,7 @@ inline constexpr bool IsCallAssigned(Opcode code) {
 }
 
 inline constexpr bool IsBranch(Opcode opcode) {
-  switch (opcode) {
-    case OP_goto:
-    case OP_brtrue:
-    case OP_brfalse:
-    case OP_switch:
-      return true;
-    default:
-      return false;
-  }
+  return (opcode == OP_goto || opcode == OP_brtrue || opcode == OP_brfalse || opcode == OP_switch);
 }
 
 constexpr bool IsStmtMustRequire(Opcode opcode) {
diff --git a/src/maple_me/include/bb.h b/src/maple_me/include/bb.h
index 03343360b68a294f43abfb85037344d2bc59cad9..ab10431631a9b7c9413bd5f60f8d68c2fc57e880 100644
--- a/src/maple_me/include/bb.h
+++ b/src/maple_me/include/bb.h
@@ -423,20 +423,6 @@ class SCCOfBBs {
   MapleSet<SCCOfBBs*> predSCC;
   MapleSet<SCCOfBBs*> succSCC;
 };
-
-inline bool ControlFlowInInfiniteLoop(const BB& bb, Opcode opcode) {
-  switch (opcode) {
-    // goto always return true
-    case OP_goto:
-      return true;
-    case OP_brtrue:
-    case OP_brfalse:
-    case OP_switch:
-      return bb.GetAttributes(kBBAttrWontExit);
-    default:
-      return false;
-  }
-}
 }  // namespace maple
 
 namespace std {
diff --git a/src/maple_me/include/me_ir.h b/src/maple_me/include/me_ir.h
index 7a564f7469b2d80f568900d0ee8f260a605059d2..a1b4e87ddf9bb524193b6f07cca58c1128ca879d 100644
--- a/src/maple_me/include/me_ir.h
+++ b/src/maple_me/include/me_ir.h
@@ -129,7 +129,7 @@ class MeExpr {
     return op == OP_gcmalloc || op == OP_gcmallocjarray || op == OP_gcpermalloc || op == OP_gcpermallocjarray;
   }
 
-  virtual bool IsVolatile(const SSATab&) {
+  virtual bool IsVolatile(const SSATab&) const {
     return false;
   }
 
@@ -217,7 +217,7 @@ class VarMeExpr final : public MeExpr {
   }
 
   BB *DefByBB();
-  bool IsVolatile(const SSATab&) override;
+  bool IsVolatile(const SSATab&) const override;
   // indicate if the variable is local variable but not a function formal variable
   bool IsPureLocal(const SSATab&, const MIRFunction&) const;
   bool IsZeroVersion(const SSATab&) const;
@@ -500,6 +500,10 @@ class RegMeExpr : public MeExpr {
     def.defMustDef = &defMustDefVal;
   }
 
+  bool IsNormalReg() const {
+    return regIdx >= 0;
+  }
+
  private:
   union {
     MeStmt *defStmt = nullptr;
@@ -923,7 +927,7 @@ class IvarMeExpr : public MeExpr {
 
   void Dump(IRMap*, int32 indent = 0) const override;
   BaseNode &EmitExpr(SSATab&) override;
-  bool IsVolatile(const SSATab&) override {
+  bool IsVolatile(const SSATab&) const override {
     return IsVolatile();
   }
 
@@ -993,7 +997,9 @@ class IvarMeExpr : public MeExpr {
   VarMeExpr *GetMu() {
     return mu;
   }
-
+  const VarMeExpr *GetMu() const {
+    return mu;
+  }
   void SetMuVal(VarMeExpr *muVal) {
     mu = muVal;
   }
diff --git a/src/maple_me/src/alias_class.cpp b/src/maple_me/src/alias_class.cpp
index dcc2448032d930109d334b12b7f43fbfc91f68c5..d97ef4c24ca812445bcdc13a03e2f3dc9e200f32 100644
--- a/src/maple_me/src/alias_class.cpp
+++ b/src/maple_me/src/alias_class.cpp
@@ -124,7 +124,7 @@ AliasElem *AliasClass::CreateAliasElemsExpr(BaseNode &expr) {
     }
     case OP_iread: {
       auto &iread = static_cast<IreadSSANode&>(expr);
-      return FindOrCreateExtraLevAliasElem(*iread.Opnd(0), iread.GetTyIdx(), iread.GetFieldID());
+      return FindOrCreateExtraLevAliasElem(utils::ToRef(iread.Opnd(0)), iread.GetTyIdx(), iread.GetFieldID());
     }
     case OP_iaddrof: {
       auto &iread = static_cast<IreadNode&>(expr);
diff --git a/src/maple_me/src/me_ir.cpp b/src/maple_me/src/me_ir.cpp
index a6fc90530650981594e18191d27156a785b48bd4..e7aec5d7893adfbfbb3c8e3cbf2e69141ee31739 100644
--- a/src/maple_me/src/me_ir.cpp
+++ b/src/maple_me/src/me_ir.cpp
@@ -1270,7 +1270,7 @@ BB *VarMeExpr::DefByBB() {
   }
 }
 
-bool VarMeExpr::IsVolatile(const SSATab &ssatab) {
+bool VarMeExpr::IsVolatile(const SSATab &ssatab) const {
   const OriginalSt *ost = ssatab.GetOriginalStFromID(ostIdx);
   if (!ost->IsSymbolOst()) {
     return false;