[she] add decGi bench for variable m

6 files changed, 280 insertions, 182 deletions

diff --git a/include/mcl/fp_tower.hpp b/include/mcl/fp_tower.hpp
index 37cc3d6..5f6fc67 100644
--- a/include/mcl/fp_tower.hpp
+++ b/include/mcl/fp_tower.hpp
@@ -140,6 +140,7 @@ public:
 	Fp2T(const std::string& a, const std::string& b, int base = 0) : a(a, base), b(b, base) {}
 	Fp* getFp0() { return &a; }
 	const Fp* getFp0() const { return &a; }
+	const Unit* getUnit() const { return a.getUnit(); }
 	void clear()
 	{
 		a.clear();
diff --git a/include/mcl/she.hpp b/include/mcl/she.hpp
index 4bdc955..4069fef 100644
--- a/include/mcl/she.hpp
+++ b/include/mcl/she.hpp
@@ -144,7 +144,7 @@ class HashTable {
 	}
 	void setWindowMethod()
 	{
-		const size_t bitSize = G::BaseFp::getBitSize();
+		const size_t bitSize = G::BaseFp::BaseFp::getBitSize();
 		wm_.init(static_cast<const I&>(P_), bitSize, local::winSize);
 	}
 public:
@@ -339,6 +339,7 @@ struct SHET {
 	static GT ePQ_; // e(P, Q)
 	static std::vector<bn_current::Fp6> Qcoeff_;
 	static local::HashTable<G1> PhashTbl_;
+	static local::HashTable<G2> QhashTbl_;
 	static mcl::fp::WindowMethod<G2> Qwm_;
 	typedef local::InterfaceForHashTable<GT, false> GTasEC;
 	static local::HashTable<GT, false> ePQhashTbl_;
@@ -460,8 +461,6 @@ public:
 		BN::hashAndMapToG2(Q_, "0");
 		BN::pairing(ePQ_, P_, Q_);
 		BN::precomputeG2(Qcoeff_, Q_);
-		const size_t bitSize = Fr::getBitSize();
-		Qwm_.init(Q_, bitSize, local::winSize);
 	}
 	/*
 		set range for G1-DLP
@@ -471,6 +470,13 @@ public:
 		PhashTbl_.init(P_, hashSize, tryNum);
 	}
 	/*
+		set range for G2-DLP
+	*/
+	static void setRangeForG2DLP(size_t hashSize, size_t tryNum = 0)
+	{
+		QhashTbl_.init(Q_, hashSize, tryNum);
+	}
+	/*
 		set range for GT-DLP
 	*/
 	static void setRangeForGTDLP(size_t hashSize, size_t tryNum = 0)
@@ -478,7 +484,7 @@ public:
 		ePQhashTbl_.init(ePQ_, hashSize, tryNum);
 	}
 	/*
-		set range for G1/GT DLP
+		set range for G1/G2/GT DLP
 		decode message m for |m| <= hasSize * tryNum
 		decode time = O(log(hasSize) * tryNum)
 		@note if tryNum = 0 then fast but require more memory(TBD)
@@ -486,6 +492,7 @@ public:
 	static void setRangeForDLP(size_t hashSize, size_t tryNum = 0)
 	{
 		setRangeForG1DLP(hashSize, tryNum);
+		setRangeForG2DLP(hashSize, tryNum);
 		setRangeForGTDLP(hashSize, tryNum);
 	}
 
@@ -541,6 +548,13 @@ public:
 			G1::sub(R, c.S_, R);
 			return PhashTbl_.log(R);
 		}
+		int64_t dec(const CipherTextG2& c) const
+		{
+			G2 R;
+			G2::mul(R, c.T_, y_);
+			G2::sub(R, c.S_, R);
+			return QhashTbl_.log(R);
+		}
 		int64_t dec(const CipherTextA& c) const
 		{
 			return dec(c.c1_);
@@ -647,7 +661,7 @@ public:
 		template<class RG>
 		void enc(CipherTextG2& c, int64_t m, RG& rg) const
 		{
-			enc1(c.S_, c.T_, Q_, yQ_, m, rg, Qwm_);
+			enc1(c.S_, c.T_, Q_, yQ_, m, rg, QhashTbl_.getWM());
 		}
 		template<class RG>
 		void enc(CipherTextA& c, int64_t m, RG& rg) const
@@ -1201,7 +1215,7 @@ template<class BN, class Fr> typename BN::G2 SHET<BN, Fr>::Q_;
 template<class BN, class Fr> typename BN::Fp12 SHET<BN, Fr>::ePQ_;
 template<class BN, class Fr> std::vector<bn_current::Fp6> SHET<BN, Fr>::Qcoeff_;
 template<class BN, class Fr> local::HashTable<typename BN::G1> SHET<BN, Fr>::PhashTbl_;
-template<class BN, class Fr> mcl::fp::WindowMethod<typename BN::G2> SHET<BN, Fr>::Qwm_;
+template<class BN, class Fr> local::HashTable<typename BN::G2> SHET<BN, Fr>::QhashTbl_;
 template<class BN, class Fr> local::HashTable<typename BN::Fp12, false> SHET<BN, Fr>::ePQhashTbl_;
 typedef mcl::she::SHET<bn_current::BN, bn_current::Fr> SHE;
 typedef SHE::SecretKey SecretKey;
diff --git a/misc/she/bench4.txt b/misc/she/bench4.txt
index e7725f6..95f7a28 100644
--- a/misc/she/bench4.txt
+++ b/misc/she/bench4.txt
@@ -8,57 +8,84 @@ ctest:module=add_mul_add_sub
 ctest:module=innerProduct
 ctest:module=io
 ctest:module=bench
-enc 676.135Kclk
-add   7.946Kclk
-mul   4.053Mclk
-dec   2.210Mclk
-add after mul  20.648Kclk
+enc 674.326Kclk
+add   7.910Kclk
+mul   4.054Mclk
+dec   2.223Mclk
+add after mul  21.223Kclk
 ctest:module=saveHash
 ctest:module=hashBench
 Kclk
-i= 0 dec(c2)=000fffff dec 2.25e+03
-i= 1 dec(c2)=001fffff dec 2.24e+03
-i= 2 dec(c2)=003fffff dec 2.19e+03
-i= 3 dec(c2)=007fffff dec 2.20e+03
-i= 4 dec(c2)=00ffffff dec 2.23e+03
-i= 5 dec(c2)=01ffffff dec 2.27e+03
-i= 6 dec(c2)=03ffffff dec 2.37e+03
-i= 7 dec(c2)=07ffffff dec 2.54e+03
-i= 8 dec(c2)=0fffffff dec 2.94e+03
-i= 9 dec(c2)=1fffffff dec 3.77e+03
-i=10 dec(c2)=3fffffff dec 5.38e+03
-i=11 dec(c2)=7fffffff dec 8.67e+03
+m=000fffff decG1 1.89e+02
+m=001fffff decG1 1.89e+02
+m=003fffff decG1 1.89e+02
+m=007fffff decG1 1.96e+02
+m=00ffffff decG1 2.11e+02
+m=01ffffff decG1 2.68e+02
+m=03ffffff decG1 4.19e+02
+m=07ffffff decG1 7.23e+02
+m=0fffffff decG1 1.30e+03
+m=1fffffff decG1 2.45e+03
+m=3fffffff decG1 4.71e+03
+m=7fffffff decG1 9.31e+03
+
+m=000fffff decG2 4.07e+02
+m=001fffff decG2 4.08e+02
+m=003fffff decG2 4.08e+02
+m=007fffff decG2 4.20e+02
+m=00ffffff decG2 4.46e+02
+m=01ffffff decG2 5.17e+02
+m=03ffffff decG2 7.20e+02
+m=07ffffff decG2 1.11e+03
+m=0fffffff decG2 1.87e+03
+m=1fffffff decG2 3.36e+03
+m=3fffffff decG2 6.38e+03
+m=7fffffff decG2 1.24e+04
+
+m=000fffff decGT 2.25e+03
+m=001fffff decGT 2.23e+03
+m=003fffff decGT 2.27e+03
+m=007fffff decGT 2.22e+03
+m=00ffffff decGT 2.25e+03
+m=01ffffff decGT 2.35e+03
+m=03ffffff decGT 2.44e+03
+m=07ffffff decGT 2.63e+03
+m=0fffffff decGT 3.00e+03
+m=1fffffff decGT 3.86e+03
+m=3fffffff decGT 5.46e+03
+m=7fffffff decGT 8.72e+03
 large m
-G1::add  7.42e-01
-G1::mul  1.86e+02
-G2::add  3.00e+00
-G2::mul  3.93e+02
-GT::mul  5.16e+00
-GT::pow  7.23e+02
-GTwindow 1.36e+02
-miller   6.71e+02
-finalExp 4.29e+02
-precomML 5.24e+02
-small m = 214346
-G1::mul  3.88e+01
-G2::mul  8.54e+01
-GT::pow  9.79e+01
-GTwindow 1.05e+01
-encG1    2.21e+02
-encG2    4.77e+02
-encGT    2.45e+03
-encGTpre 6.03e+02
-decG1    1.84e+02
-degGT    2.19e+03
-mul      4.06e+03
+G1::add  7.35e-01
+G1::mul  1.94e+02
+G2::add  3.17e+00
+G2::mul  4.04e+02
+GT::mul  5.08e+00
+GT::pow  7.44e+02
+GTwindow 1.35e+02
+miller   6.74e+02
+finalExp 4.23e+02
+precomML 5.18e+02
+small m = 2097151
+G1::mul  4.52e+01
+G2::mul  9.95e+01
+GT::pow  1.33e+02
+GTwindow 1.55e+01
+encG1    2.10e+02
+encG2    4.81e+02
+encGT    2.47e+03
+encGTpre 6.02e+02
+decG1    1.90e+02
+decG2    4.12e+02
+degGT    2.22e+03
+mul      4.07e+03
 addG1    1.56e+00
-addG2    4.72e+00
-addGT    2.04e+01
-reRandG1 2.12e+02
-reRandG2 4.76e+02
-reRandGT 2.47e+03
-reRandGTpre 6.18e+02
-mulG1    7.90e+01
-mulG2    1.65e+02
-mulGT    3.93e+02
-ctest:name=she_test, module=11, total=2809, ok=2809, ng=0, exception=0
+addG2    4.76e+00
+addGT    2.07e+01
+reRandG1 2.10e+02
+reRandG2 4.73e+02
+reRandGT 2.48e+03
+reRandGTpre 6.08e+02
+mulG1    9.21e+01
+mulG2    2.00e+02
+mulGT    5.35e+02
+ctest:name=she_test, module=11, total=2859, ok=2859, ng=0, exception=0
diff --git a/misc/she/bench6.txt b/misc/she/bench6.txt
index 5ed4ea6..d1125f1 100644
--- a/misc/she/bench6.txt
+++ b/misc/she/bench6.txt
@@ -8,57 +8,84 @@ ctest:module=add_mul_add_sub
 ctest:module=innerProduct
 ctest:module=io
 ctest:module=bench
-enc   2.098Mclk
-add  17.896Kclk
-mul  13.425Mclk
-dec   6.041Mclk
-add after mul  41.833Kclk
+enc   2.081Mclk
+add  17.729Kclk
+mul  13.522Mclk
+dec   6.002Mclk
+add after mul  42.743Kclk
 ctest:module=saveHash
 ctest:module=hashBench
 Kclk
-i= 0 dec(c2)=000fffff dec 6.00e+03
-i= 1 dec(c2)=001fffff dec 6.02e+03
-i= 2 dec(c2)=003fffff dec 6.01e+03
-i= 3 dec(c2)=007fffff dec 6.01e+03
-i= 4 dec(c2)=00ffffff dec 6.05e+03
-i= 5 dec(c2)=01ffffff dec 6.14e+03
-i= 6 dec(c2)=03ffffff dec 6.36e+03
-i= 7 dec(c2)=07ffffff dec 6.68e+03
-i= 8 dec(c2)=0fffffff dec 7.40e+03
-i= 9 dec(c2)=1fffffff dec 8.92e+03
-i=10 dec(c2)=3fffffff dec 1.20e+04
-i=11 dec(c2)=7fffffff dec 1.79e+04
+m=000fffff decG1 5.29e+02
+m=001fffff decG1 5.27e+02
+m=003fffff decG1 5.30e+02
+m=007fffff decG1 5.36e+02
+m=00ffffff decG1 5.83e+02
+m=01ffffff decG1 7.07e+02
+m=03ffffff decG1 9.52e+02
+m=07ffffff decG1 1.41e+03
+m=0fffffff decG1 2.31e+03
+m=1fffffff decG1 4.13e+03
+m=3fffffff decG1 7.73e+03
+m=7fffffff decG1 1.50e+04
+
+m=000fffff decG2 1.26e+03
+m=001fffff decG2 1.27e+03
+m=003fffff decG2 1.26e+03
+m=007fffff decG2 1.29e+03
+m=00ffffff decG2 1.35e+03
+m=01ffffff decG2 1.53e+03
+m=03ffffff decG2 1.88e+03
+m=07ffffff decG2 2.54e+03
+m=0fffffff decG2 3.86e+03
+m=1fffffff decG2 6.50e+03
+m=3fffffff decG2 1.18e+04
+m=7fffffff decG2 2.24e+04
+
+m=000fffff decGT 6.05e+03
+m=001fffff decGT 6.05e+03
+m=003fffff decGT 6.04e+03
+m=007fffff decGT 6.07e+03
+m=00ffffff decGT 6.11e+03
+m=01ffffff decGT 6.19e+03
+m=03ffffff decGT 6.42e+03
+m=07ffffff decGT 6.74e+03
+m=0fffffff decGT 7.47e+03
+m=1fffffff decGT 9.00e+03
+m=3fffffff decGT 1.21e+04
+m=7fffffff decGT 1.81e+04
 large m
 G1::add  1.48e+00
-G1::mul  5.40e+02
-G2::add  7.01e+00
-G2::mul  1.29e+03
-GT::mul  1.04e+01
-GT::pow  2.02e+03
-GTwindow 4.10e+02
-miller   2.08e+03
-finalExp 1.49e+03
-precomML 1.65e+03
-small m = 748424
-G1::mul  7.55e+01
-G2::mul  1.79e+02
-GT::pow  2.22e+02
-GTwindow 2.10e+01
-encG1    6.07e+02
+G1::mul  5.34e+02
+G2::add  6.94e+00
+G2::mul  1.22e+03
+GT::mul  1.07e+01
+GT::pow  1.96e+03
+GTwindow 4.15e+02
+miller   2.10e+03
+finalExp 1.50e+03
+precomML 1.64e+03
+small m = 2097151
+G1::mul  8.24e+01
+G2::mul  2.06e+02
+GT::pow  2.68e+02
+GTwindow 3.18e+01
+encG1    6.03e+02
 encG2    1.51e+03
-encGT    7.66e+03
-encGTpre 1.74e+03
-decG1    5.51e+02
-degGT    6.00e+03
-mul      1.34e+04
-addG1    3.08e+00
-addG2    1.03e+01
-addGT    4.26e+01
-reRandG1 6.15e+02
+encGT    7.68e+03
+encGTpre 1.75e+03
+decG1    5.28e+02
+decG2    1.29e+03
+degGT    6.05e+03
+mul      1.35e+04
+addG1    3.09e+00
+addG2    1.02e+01
+addGT    4.22e+01
+reRandG1 5.99e+02
 reRandG2 1.50e+03
-reRandGT 7.68e+03
-reRandGTpre 1.75e+03
-mulG1    1.53e+02
-mulG2    3.60e+02
-mulGT    8.85e+02
-ctest:name=she_test, module=11, total=2809, ok=2809, ng=0, exception=0
+reRandGT 7.72e+03
+reRandGTpre 1.76e+03
+mulG1    1.65e+02
+mulG2    4.13e+02
+mulGT    1.07e+03
+ctest:name=she_test, module=11, total=2859, ok=2859, ng=0, exception=0
diff --git a/misc/she/bench8.txt b/misc/she/bench8.txt
index 2471585..4f09ad7 100644
--- a/misc/she/bench8.txt
+++ b/misc/she/bench8.txt
@@ -8,57 +8,84 @@ ctest:module=add_mul_add_sub
 ctest:module=innerProduct
 ctest:module=io
 ctest:module=bench
-enc   5.103Mclk
-add  36.406Kclk
-mul  30.673Mclk
-dec  13.132Mclk
-add after mul  76.518Kclk
+enc   5.084Mclk
+add  36.299Kclk
+mul  30.169Mclk
+dec  12.705Mclk
+add after mul  77.619Kclk
 ctest:module=saveHash
 ctest:module=hashBench
 Kclk
-i= 0 dec(c2)=000fffff dec 1.28e+04
-i= 1 dec(c2)=001fffff dec 1.29e+04
-i= 2 dec(c2)=003fffff dec 1.28e+04
-i= 3 dec(c2)=007fffff dec 1.29e+04
-i= 4 dec(c2)=00ffffff dec 1.30e+04
-i= 5 dec(c2)=01ffffff dec 1.31e+04
-i= 6 dec(c2)=03ffffff dec 1.34e+04
-i= 7 dec(c2)=07ffffff dec 1.41e+04
-i= 8 dec(c2)=0fffffff dec 1.54e+04
-i= 9 dec(c2)=1fffffff dec 1.80e+04
-i=10 dec(c2)=3fffffff dec 2.33e+04
-i=11 dec(c2)=7fffffff dec 3.37e+04
+m=000fffff decG1 1.43e+03
+m=001fffff decG1 1.44e+03
+m=003fffff decG1 1.43e+03
+m=007fffff decG1 1.46e+03
+m=00ffffff decG1 1.54e+03
+m=01ffffff decG1 1.69e+03
+m=03ffffff decG1 2.02e+03
+m=07ffffff decG1 2.64e+03
+m=0fffffff decG1 3.89e+03
+m=1fffffff decG1 6.37e+03
+m=3fffffff decG1 1.13e+04
+m=7fffffff decG1 2.13e+04
+
+m=000fffff decG2 3.00e+03
+m=001fffff decG2 3.01e+03
+m=003fffff decG2 3.00e+03
+m=007fffff decG2 3.05e+03
+m=00ffffff decG2 3.16e+03
+m=01ffffff decG2 3.43e+03
+m=03ffffff decG2 3.94e+03
+m=07ffffff decG2 4.95e+03
+m=0fffffff decG2 6.95e+03
+m=1fffffff decG2 1.10e+04
+m=3fffffff decG2 1.91e+04
+m=7fffffff decG2 3.52e+04
+
+m=000fffff decGT 1.29e+04
+m=001fffff decGT 1.29e+04
+m=003fffff decGT 1.29e+04
+m=007fffff decGT 1.29e+04
+m=00ffffff decGT 1.30e+04
+m=01ffffff decGT 1.32e+04
+m=03ffffff decGT 1.35e+04
+m=07ffffff decGT 1.41e+04
+m=0fffffff decGT 1.54e+04
+m=1fffffff decGT 1.80e+04
+m=3fffffff decGT 2.32e+04
+m=7fffffff decGT 3.37e+04
 large m
-G1::add  4.67e+00
-G1::mul  1.42e+03
-G2::add  1.37e+01
-G2::mul  2.93e+03
-GT::mul  1.95e+01
-GT::pow  4.24e+03
-GTwindow 1.00e+03
-miller   5.24e+03
-finalExp 3.52e+03
-precomML 4.00e+03
-small m = 34209
-G1::mul  1.23e+02
-G2::mul  2.84e+02
-GT::pow  3.32e+02
-GTwindow 4.04e+01
-encG1    1.70e+03
-encG2    3.67e+03
-encGT    1.87e+04
-encGTpre 3.77e+03
-decG1    1.52e+03
-degGT    1.32e+04
-mul      3.11e+04
-addG1    7.21e+00
-addG2    2.09e+01
-addGT    8.04e+01
-reRandG1 1.66e+03
-reRandG2 3.58e+03
-reRandGT 1.83e+04
+G1::add  3.42e+00
+G1::mul  1.48e+03
+G2::add  1.38e+01
+G2::mul  2.90e+03
+GT::mul  1.92e+01
+GT::pow  4.32e+03
+GTwindow 9.01e+02
+miller   4.86e+03
+finalExp 3.25e+03
+precomML 3.74e+03
+small m = 2097151
+G1::mul  1.53e+02
+G2::mul  3.87e+02
+GT::pow  4.89e+02
+GTwindow 5.82e+01
+encG1    1.68e+03
+encG2    3.48e+03
+encGT    1.78e+04
+encGTpre 3.76e+03
+decG1    1.48e+03
+decG2    2.96e+03
+degGT    1.30e+04
+mul      3.10e+04
+addG1    6.92e+00
+addG2    2.05e+01
+addGT    7.66e+01
+reRandG1 1.65e+03
+reRandG2 3.48e+03
+reRandGT 1.77e+04
 reRandGTpre 3.78e+03
-mulG1    2.36e+02
-mulG2    5.55e+02
-mulGT    1.30e+03
-ctest:name=she_test, module=11, total=2809, ok=2809, ng=0, exception=0
+mulG1    3.07e+02
+mulG2    7.69e+02
+mulGT    1.96e+03
+ctest:name=she_test, module=11, total=2859, ok=2859, ng=0, exception=0
diff --git a/test/she_test.cpp b/test/she_test.cpp
index 8d3e3e5..3869ed7 100644
--- a/test/she_test.cpp
+++ b/test/she_test.cpp
@@ -282,44 +282,47 @@ CYBOZU_TEST_AUTO(saveHash)
 
 static inline void putK(double t) { printf("%.2e\n", t * 1e-3); }
 
+template<class CT>
+void decBench(const char *msg, int C, const SecretKey& sec, const PublicKey& pub)
+{
+	int64_t begin = 1 << 20;
+	int64_t end = 1LL << 32;
+	while (begin < end) {
+		CT c;
+		int64_t x = begin - 1;
+		pub.enc(c, x);
+		printf("m=%08x ", (uint32_t)x);
+		CYBOZU_BENCH_C(msg, C, sec.dec, c);
+		CYBOZU_TEST_EQUAL(sec.dec(c), x);
+		begin *= 2;
+	}
+	int64_t mTbl[] = { -0x80000003ll, 0x80000000ll, 0x80000005ll };
+	for (size_t i = 0; i < CYBOZU_NUM_OF_ARRAY(mTbl); i++) {
+		int64_t m = mTbl[i];
+		CT c;
+		pub.enc(c, m);
+		CYBOZU_TEST_EQUAL(sec.dec(c), m);
+	}
+}
+
 CYBOZU_TEST_AUTO(hashBench)
 {
 	SecretKey& sec = g_sec;
 	sec.setByCSPRNG();
+	const int C = 500;
 	const size_t hashSize = 1u << 21;
 	SHE::setRangeForDLP(hashSize, 1024);
 	PublicKey pub;
 	sec.getPublicKey(pub);
 	PrecomputedPublicKey ppub;
 	ppub.init(pub);
-	{
-		int x = 1 << 20;
-		CipherText one;
-		CipherText c1;
-		pub.enc(c1, x);
-		pub.enc(one, 1, true);
-
-		puts("Kclk");
-		cybozu::bench::setPutCallback(putK);
-		for (int i = 0; i < 12; i++) {
-			int y = 1 << i;
-			CipherText c2;
-			pub.enc(c2, y);
-			c2.mul(c1);
-			c2.sub(one);
-			int expect = x * y - 1;
-			CYBOZU_TEST_EQUAL(sec.dec(c2), expect);
-			printf("i=%2d dec(c2)=%08x ", i, expect);
-			CYBOZU_BENCH_C("dec", 100, sec.dec, c2);
-		}
-		// larger than int32_t
-		int64_t mTbl[] = { -0x80000003ll, 0x80000000ll, 0x80000005ll };
-		for (size_t i = 0; i < CYBOZU_NUM_OF_ARRAY(mTbl); i++) {
-			int64_t m = mTbl[i];
-			pub.enc(c1, m);
-			CYBOZU_TEST_EQUAL(sec.dec(c1), m);
-		}
-	}
+	puts("Kclk");
+	cybozu::bench::setPutCallback(putK);
+	decBench<CipherTextG1>("decG1", C, sec, pub);
+	puts("");
+	decBench<CipherTextG2>("decG2", C, sec, pub);
+	puts("");
+	decBench<CipherTextGT>("decGT", C, sec, pub);
 
 	G1 P, P2;
 	G2 Q, Q2;
@@ -333,7 +336,6 @@ CYBOZU_TEST_AUTO(hashBench)
 	BN::hashAndMapToG1(P, "abc");
 	BN::hashAndMapToG2(Q, "abc");
 	BN::pairing(e, P, Q);
-	const int C = 100;
 	P2.clear();
 	Q2.clear();
 	e2 = 1;
@@ -366,7 +368,7 @@ CYBOZU_TEST_AUTO(hashBench)
 	CipherTextG2 ca2;
 	CipherTextM cm;
 
-	int m = int(mcl::she::local::g_rg() % hashSize);
+	int m = int(hashSize - 1);
 	printf("small m = %d\n", m);
 	CYBOZU_BENCH_C("G1::mul ", C, G1::mul, P, P, m);
 	CYBOZU_BENCH_C("G2::mul ", C, G2::mul, Q, Q, m);
@@ -379,7 +381,7 @@ CYBOZU_TEST_AUTO(hashBench)
 	CYBOZU_BENCH_C("encGTpre", C, ppub.enc, cm, m);
 
 	CYBOZU_BENCH_C("decG1   ", C, sec.dec, ca1);
-//	CYBOZU_BENCH_C("decG2   ", C, sec.dec, ca2);
+	CYBOZU_BENCH_C("decG2   ", C, sec.dec, ca2);
 	CYBOZU_BENCH_C("degGT   ", C, sec.dec, cm);
 
 	CYBOZU_BENCH_C("mul     ", C, CipherTextM::mul, cm, ca1, ca2);