diff --git a/include/mcl/fp_tower.hpp b/include/mcl/fp_tower.hpp
index 3acff3f..31f97c8 100644
--- a/include/mcl/fp_tower.hpp
+++ b/include/mcl/fp_tower.hpp
@@ -141,27 +141,14 @@ public:
 	static void addA(Unit *z, const Unit *x, const Unit *y) { Fp::op_.fpDbl_add(z, x, y, Fp::op_.p); }
 	static void subA(Unit *z, const Unit *x, const Unit *y) { Fp::op_.fpDbl_sub(z, x, y, Fp::op_.p); }
 	static void modA(Unit *z, const Unit *xy) { Fp::op_.fpDbl_mod(z, xy, Fp::op_.p); }
-	static void (*addPre)(FpDblT& z, const FpDblT& x, const FpDblT& y);
-	static void (*subPre)(FpDblT& z, const FpDblT& x, const FpDblT& y);
-	static void addPreC(FpDblT& z, const FpDblT& x, const FpDblT& y) { Fp::op_.fpDbl_addPre(z.v_, x.v_, y.v_); }
-	static void subPreC(FpDblT& z, const FpDblT& x, const FpDblT& y) { Fp::op_.fpDbl_subPre(z.v_, x.v_, y.v_); }
-#else
+#endif
 	static void addPre(FpDblT& z, const FpDblT& x, const FpDblT& y) { Fp::op_.fpDbl_addPre(z.v_, x.v_, y.v_); }
 	static void subPre(FpDblT& z, const FpDblT& x, const FpDblT& y) { Fp::op_.fpDbl_subPre(z.v_, x.v_, y.v_); }
-#endif
 	/*
 		mul(z, x, y) = mulPre(xy, x, y) + mod(z, xy)
 	*/
-	static void mulPre(FpDblT& xy, const Fp& x, const Fp& y)
-	{
-		const mcl::fp::Op& op = Fp::getOp();
-		op.fpDbl_mulPre(xy.v_, x.v_, y.v_);
-	}
-	static void sqrPre(FpDblT& xx, const Fp& x)
-	{
-		const mcl::fp::Op& op = Fp::getOp();
-		op.fpDbl_sqrPre(xx.v_, x.v_);
-	}
+	static void mulPre(FpDblT& xy, const Fp& x, const Fp& y) { Fp::op_.fpDbl_mulPre(xy.v_, x.v_, y.v_); }
+	static void sqrPre(FpDblT& xx, const Fp& x) { Fp::op_.fpDbl_sqrPre(xx.v_, x.v_); }
 	static void mulUnit(FpDblT& z, const FpDblT& x, Unit y)
 	{
 		if (mulSmallUnit(z, x, y)) return;
@@ -170,7 +157,7 @@ public:
 	static void init()
 	{
 #ifdef MCL_XBYAK_DIRECT_CALL
-		mcl::fp::Op& op = Fp::getOpNonConst();
+		mcl::fp::Op& op = Fp::op_;
 		if (op.fpDbl_addA_ == 0) {
 			op.fpDbl_addA_ = addA;
 		}
@@ -180,21 +167,12 @@ public:
 		if (op.fpDbl_modA_ == 0) {
 			op.fpDbl_modA_ = modA;
 		}
-		addPre = fp::func_ptr_cast<void (*)(FpDblT&, const FpDblT&, const FpDblT&)>(op.fpDbl_addPre);
-		if (addPre == 0) addPre = addPreC;
-		subPre = fp::func_ptr_cast<void (*)(FpDblT&, const FpDblT&, const FpDblT&)>(op.fpDbl_subPre);
-		if (subPre == 0) subPre = subPreC;
 #endif
 	}
 	void operator+=(const FpDblT& x) { add(*this, *this, x); }
 	void operator-=(const FpDblT& x) { sub(*this, *this, x); }
 };
 
-#ifdef MCL_XBYAK_DIRECT_CALL
-template<class Fp> void (*FpDblT<Fp>::addPre)(FpDblT&, const FpDblT&, const FpDblT&);
-template<class Fp> void (*FpDblT<Fp>::subPre)(FpDblT&, const FpDblT&, const FpDblT&);
-#endif
-
 /*
 	beta = -1
 	Fp2 = F[i] / (i^2 + 1)