add test of edge of Fp::mul

include/mcl/bn.hpp

@@ -149,8 +149,8 @@ struct ParamT {
 		half = Fp(1) / Fp(2);
 		Fp2 xi(cp.xi_a, 1);
 		b_invxi = Fp2(b) / xi;
-		G1::setParam(Fp(0), Fp(b));
-		G2::setParam(Fp2(0), b_invxi);
+		G1::setParam(0, b);
+		G2::setParam(0, b_invxi);
 		power(gammar[0], xi, (p - 1) / 6);
 
 		for (size_t i = 1; i < gammarN; i++) {
@@ -224,17 +224,12 @@ struct Naive {
 		f = 1;
 		const int c = (int)mcl::gmp::getBitSize(r);
 		for (int i = c - 2; i >= 0; i--) {
-printf("i=%d\n", i);
 			Fp12::sqr(f, f);
 			evalLine(t, T, T, P);
-PUT(t);
 			f *= t;
 			G2::dbl(T, T);
-PUT(T);
 			if (mcl::gmp::testBit(r, i)) {
 				evalLine(t, T, Q, P);
-puts("in");
-PUT(t);
 				f *= t;
 				T += Q;
 			}

test/fp_tower_test.cpp

@@ -36,8 +36,8 @@ void testFp2()
 	y.a = 3;
 	y.b = 4;
 	/*
-		x = 1 + 2u
-		y = 3 + 4u
+		x = 1 + 2i
+		y = 3 + 4i
 	*/
 	add(z, x, y);
 	CYBOZU_TEST_EQUAL(z, Fp2(4, 6));
@@ -45,18 +45,18 @@ void testFp2()
 	CYBOZU_TEST_EQUAL(z, Fp2(-2, -2));
 	mul(z, x, y);
 	/*
-		(1 + 2u)(3 + 4u) = (3 - 8) + (4 + 6)u = -5 + 10u
+		(1 + 2i)(3 + 4i) = (3 - 8) + (4 + 6)i = -5 + 10i
 	*/
 	CYBOZU_TEST_EQUAL(z, Fp2(-5, 10));
 	neg(z, z);
 	CYBOZU_TEST_EQUAL(z, Fp2(5, -10));
 	/*
-		xi = 9 + u
-		(1 - 2u)(9 + u) = (9 + 2) + (1 - 18)u = 11 - 17u
+		xi = xi_a + i
+		(1 - 2i)(xi_a + i) = (xi_a + 2) + (1 - 2 xi_a)i
 	*/
 	z = Fp2(1, -2);
 	Fp2::mulXi(z, z);
-	CYBOZU_TEST_EQUAL(z, Fp2(11, -17));
+	CYBOZU_TEST_EQUAL(z, Fp2(Fp2::getXi_a() + 2, Fp2::getXi_a() * (-2) + 1));
 	z = x * x;
 	sqr(y, x);
 	CYBOZU_TEST_EQUAL(z, y);
@@ -92,6 +92,24 @@ void testFp2()
 		}
 		CYBOZU_TEST_EQUAL(z, y);
 	}
+	{
+		mpz_class t = Fp::getOp().mp;
+		t /= 2;
+		Fp x;
+		x.setMpz(t);
+		CYBOZU_TEST_EQUAL(x * 2, Fp(-1));
+		t += 1;
+		x.setMpz(t);
+		CYBOZU_TEST_EQUAL(x * 2, 1);
+	}
+	{
+		Fp2 a(1, 1);
+		Fp2 b(1, -1);
+		Fp2 c(Fp2(2) / a);
+		CYBOZU_TEST_EQUAL(c, b);
+		CYBOZU_TEST_EQUAL(a * b, Fp2(2));
+		CYBOZU_TEST_EQUAL(a * c, Fp2(2));
+	}
 	y = x;
 	inv(y, x);
 	y *= x;
@@ -322,7 +340,7 @@ void test(const char *p, mcl::fp::Mode mode)
 {
 	Fp::setModulo(p, 0, mode);
 	printf("mode=%s\n", mcl::fp::ModeToStr(mode));
-	const int xi_a = 9;
+	const int xi_a = 1;
 	Fp2::init(xi_a);
 	if (Fp::getBitSize() > 256) {
 		printf("not support p=%s\n", p);
@@ -370,13 +388,13 @@ void testAll()
 	for (size_t i = 0; i < CYBOZU_NUM_OF_ARRAY(tbl); i++) {
 		const char *p = tbl[i];
 		printf("prime=%s %d\n", p, (int)(strlen(p) - 2) * 4);
-		test(tbl[i], mcl::fp::FP_GMP);
+		test(p, mcl::fp::FP_GMP);
 #ifdef MCL_USE_LLVM
-		test(tbl[i], mcl::fp::FP_LLVM);
-		test(tbl[i], mcl::fp::FP_LLVM_MONT);
+		test(p, mcl::fp::FP_LLVM);
+		test(p, mcl::fp::FP_LLVM_MONT);
 #endif
 #ifdef MCL_USE_XBYAK
-		test(tbl[i], mcl::fp::FP_XBYAK);
+		test(p, mcl::fp::FP_XBYAK);
 #endif
 	}
 }