test is ok on mont

include/mcl/fp.hpp

@@ -103,20 +103,20 @@ public:
 #endif
 		if (mode == fp::FP_AUTO) mode = fp::FP_GMP;
 
-		op_.useMont = mode == fp::FP_LLVM_MONT || mode == fp::FP_XBYAK;
+		op_.isMont = mode == fp::FP_LLVM_MONT || mode == fp::FP_XBYAK;
 		if (mode == fp::FP_LLVM_MONT) {
 			op_.fp_mul = fp_montW;
 			op_.fp_sqr = fp_montSqrW;
 		}
 #if 0
-	fprintf(stderr, "mode=%d, useMont=%d"
+	fprintf(stderr, "mode=%d, isMont=%d"
 #ifdef MCL_USE_XBYAK
 		" ,MCL_USE_XBYAK"
 #endif
 #ifdef MCL_USE_LLVM
 		" ,MCL_USE_LLVM"
 #endif
-	"\n", mode, op_.useMont);
+	"\n", mode, op_.isMont);
 #endif
 		op_.init(mstr, base, maxBitSize, mode);
 		{ // set oneRep
@@ -195,22 +195,22 @@ public:
 		}
 		return *this;
 	}
-	static inline bool useMont() { return op_.useMont; }
+	static inline bool isMont() { return op_.isMont; }
 	/*
 		convert normal value to Montgomery value
-		do nothing is !useMont()
+		do nothing is !isMont()
 	*/
 	void toMont()
 	{
-		if (useMont()) op_.toMont(v_, v_);
+		if (isMont()) op_.toMont(v_, v_);
 	}
 	/*
 		convert Montgomery value to normal value
-		do nothing is !useMont()
+		do nothing is !isMont()
 	*/
 	void fromMont()
 	{
-		if (useMont()) op_.fromMont(v_, v_);
+		if (isMont()) op_.fromMont(v_, v_);
 	}
 	void setStr(const std::string& str, int base = 0)
 	{
@@ -257,7 +257,7 @@ public:
 	void getBlock(fp::Block& b) const
 	{
 		b.n = op_.N;
-		if (useMont()) {
+		if (isMont()) {
 			op_.fromMont(b.v_, v_);
 			b.p = &b.v_[0];
 		} else {
@@ -392,7 +392,7 @@ public:
 	}
 	/*
 		@note
-		this compare functions is slow because of calling mul if useMont is true.
+		this compare functions is slow because of calling mul if isMont is true.
 	*/
 	static inline int compare(const FpT& x, const FpT& y)
 	{
@@ -414,7 +414,7 @@ public:
 	bool operator<=(const FpT& rhs) const { return !operator>(rhs); }
 	/*
 		@note
-		return unexpected order if useMont is set.
+		return unexpected order if isMont is set.
 	*/
 	static inline int compareRaw(const FpT& x, const FpT& y)
 	{

include/mcl/fp_tower.hpp

@@ -45,6 +45,7 @@ public:
 	static inline void addNC(FpDblT& z, const FpDblT& x, const FpDblT& y) { Fp::op_.fpDbl_addNC(z.v_, x.v_, y.v_); }
 	static inline void subNC(FpDblT& z, const FpDblT& x, const FpDblT& y) { Fp::op_.fpDbl_subNC(z.v_, x.v_, y.v_); }
 	static inline void mulPre(FpDblT& z, const Fp& x, const Fp& y) { Fp::op_.fp_mulPre(z.v_, x.v_, y.v_); }
+	static inline void mod(Fp& y, const FpDblT& x) { Fp::op_.fp_mod(y.v_, x.v_); }
 };
 
 /*

include/mcl/op.hpp

@@ -100,7 +100,7 @@ struct Op {
 	void3u fp_addNC; // assume no carry if !isFullBit
 	void3u fp_subNC; // assume x > y
 	// for Montgomery
-	bool useMont;
+	bool isMont;
 	int2u fp_preInv;
 	// these two members are for mcl_fp_mont
 	Unit rp;
@@ -149,7 +149,7 @@ struct Op {
 		, fp_isZero(0), fp_clear(0), fp_copy(0)
 		, fp_neg(0), fp_sqr(0), fp_add(0), fp_sub(0), fp_mul(0)
 		, isFullBit(true), fp_addNC(0), fp_subNC(0)
-		, useMont(false), fp_preInv(0)
+		, isMont(false), fp_preInv(0)
 		, rp(0), mont(0)
 		, fp_negP(0), fp_invOp(0), fp_addP(0), fp_subP(0), fp_modP(0)
 		, fg(createFpGenerator())

src/fp.cpp

@@ -286,7 +286,7 @@ struct OpeFunc {
 		fp_clear = OpeFunc<n>::fp_clearC; \
 		fp_copy = OpeFunc<n>::fp_copyC; \
 		fp_negP = OpeFunc<n>::fp_negC; \
-		if (useMont) { \
+		if (isMont) { \
 			fp_invOp = OpeFunc<n>::fp_invMontOpC; \
 		} else { \
 			fp_invOp = OpeFunc<n>::fp_invOpC; \
@@ -417,10 +417,10 @@ void Op::init(const std::string& mstr, int base, size_t maxBitSize, Mode mode)
 #ifdef MCL_USE_LLVM
 	if (mode == FP_AUTO && mp == mpz_class("0xfffffffffffffffffffffffffffffffeffffffffffffffff")) {
 		fp_mul = &mcl_fp_mul_NIST_P192;
-		useMont = false;
+		isMont = false;
 	}
 #endif
-	if (useMont) {
+	if (isMont) {
 		fp::initForMont(*this, p, mode);
 	}
 	sq.set(mp);

test/fp_tower_test.cpp

@@ -1,6 +1,7 @@
 #define PUT(x) std::cout << #x "=" << (x) << std::endl
 #include <cybozu/test.hpp>
 #include <cybozu/benchmark.hpp>
+#include <cybozu/xorshift.hpp>
 #include <time.h>
 #include <mcl/fp.hpp>
 #include <mcl/fp_tower.hpp>
@@ -110,6 +111,30 @@ void testFpDbl()
 			}
 		}
 	}
+	{
+		std::string pstr;
+		Fp::getModulo(pstr);
+		const mpz_class mp(pstr);
+		cybozu::XorShift rg;
+		for (int i = 0; i < 3; i++) {
+			Fp x, y, z;
+			mpz_class mx, my, mz, mo;
+			x.setRand(rg);
+			x.fromMont();
+			x.getMpz(mx);
+			y.setRand(rg);
+			y.fromMont();
+			y.getMpz(my);
+			mo = mx * my;
+			FpDbl xy;
+			FpDbl::mulPre(xy, x, y);
+			FpDbl::mod(z, xy);
+			z.fromMont();
+			z.getMpz(mz);
+			mo %= mp;
+			CYBOZU_TEST_EQUAL(mz, mo);
+		}
+	}
 }
 
 void test(const char *p, mcl::fp::Mode mode)