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add Straus multiexp

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release-v0.5.1
moneromooo-monero 6 years ago
parent 9ff6e6a0a7
commit 939bc22332
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GPG Key ID: 686F07454D6CEFC3
6 changed files with 279 additions and 150 deletions
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190
src/ringct/bulletproofs.cc
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@ -67,6 +67,14 @@ static const rct::keyV twoN = vector_powers(TWO, maxN);
static const rct::key ip12 = inner_product(oneN, twoN);
static boost::mutex init_mutex;
static inline rct::key multiexp(const std::vector<MultiexpData> &data, bool HiGi)
{
if (HiGi || data.size() < 1000)
return straus(data, HiGi);
else
return bos_coster_heap_conv_robust(data);
}
//addKeys3acc_p3
//aAbB += a*A + b*B where a, b are scalars, A, B are curve points
//A and B must be input after applying "precomp"
@ -126,35 +134,15 @@ static rct::key vector_exponent(const rct::keyV &a, const rct::keyV &b)
{
CHECK_AND_ASSERT_THROW_MES(a.size() == b.size(), "Incompatible sizes of a and b");
CHECK_AND_ASSERT_THROW_MES(a.size() <= maxN*maxM, "Incompatible sizes of a and maxN");
#if 1
std::vector<MultiexpData> multiexp_data;
multiexp_data.reserve(a.size()*2);
for (size_t i = 0; i < a.size(); ++i)
{
if (!(a[i] == rct::zero()))
{
multiexp_data.resize(multiexp_data.size() + 1);
multiexp_data.back().scalar = a[i];
multiexp_data.back().point = Gi_p3[i];
}
if (!(b[i] == rct::zero()))
{
multiexp_data.resize(multiexp_data.size() + 1);
multiexp_data.back().scalar = b[i];
multiexp_data.back().point = Hi_p3[i];
}
multiexp_data.emplace_back(a[i], Gi_p3[i]);
multiexp_data.emplace_back(b[i], Hi_p3[i]);
}
return bos_coster_heap_conv_robust(multiexp_data);
#else
ge_p3 res_p3 = ge_p3_identity;
for (size_t i = 0; i < a.size(); ++i)
{
rct::addKeys3acc_p3(&res_p3, a[i], Gprecomp[i], b[i], Hprecomp[i]);
}
rct::key res;
ge_p3_tobytes(res.bytes, &res_p3);
return res;
#endif
return multiexp(multiexp_data, true);
}
/* Compute a custom vector-scalar commitment */
@ -164,63 +152,19 @@ static rct::key vector_exponent_custom(const rct::keyV &A, const rct::keyV &B, c
CHECK_AND_ASSERT_THROW_MES(a.size() == b.size(), "Incompatible sizes of a and b");
CHECK_AND_ASSERT_THROW_MES(a.size() == A.size(), "Incompatible sizes of a and A");
CHECK_AND_ASSERT_THROW_MES(a.size() <= maxN*maxM, "Incompatible sizes of a and maxN");
#if 1
std::vector<MultiexpData> multiexp_data;
multiexp_data.reserve(a.size()*2);
for (size_t i = 0; i < a.size(); ++i)
{
if (!(a[i] == rct::zero()))
{
multiexp_data.resize(multiexp_data.size() + 1);
multiexp_data.back().scalar = a[i];
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&multiexp_data.back().point, A[i].bytes) == 0, "ge_frombytes_vartime failed");
}
if (!(b[i] == rct::zero()))
{
multiexp_data.resize(multiexp_data.size() + 1);
multiexp_data.back().scalar = b[i];
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&multiexp_data.back().point, B[i].bytes) == 0, "ge_frombytes_vartime failed");
}
}
return bos_coster_heap_conv_robust(multiexp_data);
#else
ge_p3 res_p3 = ge_p3_identity;
for (size_t i = 0; i < a.size(); ++i)
{
#if 0
rct::key term;
// we happen to know where A and B might fall, so don't bother checking the rest
ge_dsmp *Acache = NULL, *Bcache = NULL;
ge_dsmp Acache_custom[1], Bcache_custom[1];
if (Gi[i] == A[i])
Acache = Gprecomp + i;
else if (i<32 && Gi[i+32] == A[i])
Acache = Gprecomp + i + 32;
else
{
rct::precomp(Acache_custom[0], A[i]);
Acache = Acache_custom;
}
if (i == 0 && B[i] == Hi[0])
Bcache = Hprecomp;
else
{
rct::precomp(Bcache_custom[0], B[i]);
Bcache = Bcache_custom;
}
rct::addKeys3(term, a[i], *Acache, b[i], *Bcache);
rct::addKeys(res, res, term);
#else
ge_dsmp Acache, Bcache;
rct::precomp(Bcache, B[i]);
rct::precomp(Acache, A[i]);
addKeys3acc_p3(&res_p3, a[i], Acache, b[i], Bcache);
#endif
multiexp_data.resize(multiexp_data.size() + 1);
multiexp_data.back().scalar = a[i];
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&multiexp_data.back().point, A[i].bytes) == 0, "ge_frombytes_vartime failed");
multiexp_data.resize(multiexp_data.size() + 1);
multiexp_data.back().scalar = b[i];
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&multiexp_data.back().point, B[i].bytes) == 0, "ge_frombytes_vartime failed");
}
rct::key res;
ge_p3_tobytes(res.bytes, &res_p3);
return res;
#endif
return multiexp(multiexp_data, false);
}
/* Given a scalar, construct a vector of powers */
@ -986,26 +930,23 @@ bool bulletproof_VERIFY(const Bulletproof &proof)
}
PERF_TIMER_STOP(VERIFY_line_61);
// multiexp is slower for small numbers of calcs
if (M >= 16)
// bos coster is slower for small numbers of calcs, straus seems not
if (1)
{
PERF_TIMER_START_BP(VERIFY_line_61rl_new);
sc_muladd(tmp.bytes, z.bytes, ip1y.bytes, k.bytes);
std::vector<MultiexpData> multiexp_data;
multiexp_data.reserve(3+M);
multiexp_data.push_back({tmp, rct::H});
for (size_t j = 0; j < M; j++)
multiexp_data.reserve(3+proof.V.size());
multiexp_data.emplace_back(tmp, rct::H);
for (size_t j = 0; j < proof.V.size(); j++)
{
if (!(zpow[j+2] == rct::zero()))
multiexp_data.push_back({zpow[j+2], j < proof.V.size() ? proof.V[j] : rct::identity()});
multiexp_data.emplace_back(zpow[j+2], proof.V[j]);
}
if (!(x == rct::zero()))
multiexp_data.push_back({x, proof.T1});
multiexp_data.emplace_back(x, proof.T1);
rct::key xsq;
sc_mul(xsq.bytes, x.bytes, x.bytes);
if (!(xsq == rct::zero()))
multiexp_data.push_back({xsq, proof.T2});
L61Right = bos_coster_heap_conv_robust(multiexp_data);
multiexp_data.emplace_back(xsq, proof.T2);
L61Right = multiexp(multiexp_data, false);
PERF_TIMER_STOP(VERIFY_line_61rl_new);
}
else
@ -1114,10 +1055,8 @@ bool bulletproof_VERIFY(const Bulletproof &proof)
sc_muladd(tmp.bytes, z.bytes, ypow.bytes, tmp.bytes);
sc_mulsub(h_scalar.bytes, tmp.bytes, yinvpow.bytes, h_scalar.bytes);
if (!(g_scalar == rct::zero()))
multiexp_data.push_back({g_scalar, Gi_p3[i]});
if (!(h_scalar == rct::zero()))
multiexp_data.push_back({h_scalar, Hi_p3[i]});
multiexp_data.emplace_back(g_scalar, Gi_p3[i]);
multiexp_data.emplace_back(h_scalar, Hi_p3[i]);
if (i != MN-1)
{
@ -1126,63 +1065,28 @@ bool bulletproof_VERIFY(const Bulletproof &proof)
}
}
rct::key inner_prod = bos_coster_heap_conv_robust(multiexp_data);
rct::key inner_prod = multiexp(multiexp_data, true);
PERF_TIMER_STOP(VERIFY_line_24_25);
// PAPER LINE 26
rct::key pprime;
// multiexp does not seem to give any speedup here
if(0)
{
PERF_TIMER_START_BP(VERIFY_line_26_new);
// PAPER LINE 26
std::vector<MultiexpData> multiexp_data;
multiexp_data.reserve(1+2*rounds);
sc_sub(tmp.bytes, rct::zero().bytes, proof.mu.bytes);
rct::addKeys(pprime, P, rct::scalarmultBase(tmp));
for (size_t i = 0; i < rounds; ++i)
{
sc_mul(tmp.bytes, w[i].bytes, w[i].bytes);
sc_mul(tmp2.bytes, winv[i].bytes, winv[i].bytes);
if (!(tmp == rct::zero()))
multiexp_data.push_back({tmp, proof.L[i]});
if (!(tmp2 == rct::zero()))
multiexp_data.push_back({tmp2, proof.R[i]});
}
sc_mul(tmp.bytes, proof.t.bytes, x_ip.bytes);
if (!(tmp == rct::zero()))
multiexp_data.push_back({tmp, rct::H});
addKeys(pprime, pprime, bos_coster_heap_conv_robust(multiexp_data));
PERF_TIMER_STOP(VERIFY_line_26_new);
}
PERF_TIMER_START_BP(VERIFY_line_26_new);
multiexp_data.clear();
multiexp_data.reserve(1+2*rounds);
sc_sub(tmp.bytes, rct::zero().bytes, proof.mu.bytes);
rct::addKeys(pprime, P, rct::scalarmultBase(tmp));
for (size_t i = 0; i < rounds; ++i)
{
PERF_TIMER_START_BP(VERIFY_line_26_old);
// PAPER LINE 26
sc_sub(tmp.bytes, rct::zero().bytes, proof.mu.bytes);
rct::addKeys(pprime, P, rct::scalarmultBase(tmp));
ge_p3 pprime_p3;
CHECK_AND_ASSERT_MES(ge_frombytes_vartime(&pprime_p3, pprime.bytes) == 0, false, "ge_frombytes_vartime failed");
for (size_t i = 0; i < rounds; ++i)
{
sc_mul(tmp.bytes, w[i].bytes, w[i].bytes);
sc_mul(tmp2.bytes, winv[i].bytes, winv[i].bytes);
#if 1
ge_dsmp cacheL, cacheR;
rct::precomp(cacheL, proof.L[i]);
rct::precomp(cacheR, proof.R[i]);
addKeys3acc_p3(&pprime_p3, tmp, cacheL, tmp2, cacheR);
#else
rct::addKeys(pprime, pprime, rct::scalarmultKey(proof.L[i], tmp));
rct::addKeys(pprime, pprime, rct::scalarmultKey(proof.R[i], tmp2));
#endif
}
sc_mul(tmp.bytes, proof.t.bytes, x_ip.bytes);
addKeys_acc_p3(&pprime_p3, tmp, rct::H);
ge_p3_tobytes(pprime.bytes, &pprime_p3);
PERF_TIMER_STOP(VERIFY_line_26_old);
sc_mul(tmp.bytes, w[i].bytes, w[i].bytes);
sc_mul(tmp2.bytes, winv[i].bytes, winv[i].bytes);
multiexp_data.emplace_back(tmp, proof.L[i]);
multiexp_data.emplace_back(tmp2, proof.R[i]);
}
sc_mul(tmp.bytes, proof.t.bytes, x_ip.bytes);
multiexp_data.emplace_back(tmp, rct::H);
addKeys(pprime, pprime, multiexp(multiexp_data, false));
PERF_TIMER_STOP(VERIFY_line_26_new);
PERF_TIMER_START_BP(VERIFY_step2_check);
sc_mul(tmp.bytes, proof.a.bytes, proof.b.bytes);

137
src/ringct/multiexp.cc
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@ -38,7 +38,7 @@ extern "C"
#include "multiexp.h"
#undef MONERO_DEFAULT_LOG_CATEGORY
#define MONERO_DEFAULT_LOG_CATEGORY "multiexp.boscoster"
#define MONERO_DEFAULT_LOG_CATEGORY "multiexp"
//#define MULTIEXP_PERF(x) x
#define MULTIEXP_PERF(x)
@ -71,7 +71,15 @@ static inline rct::key div2(const rct::key &k)
return res;
}
rct::key bos_coster_heap_conv(std::vector<MultiexpData> &data)
static inline rct::key pow2(size_t n)
{
CHECK_AND_ASSERT_THROW_MES(n < 256, "Invalid pow2 argument");
rct::key res = rct::zero();
res[n >> 3] |= 1<<(n&7);
return res;
}
rct::key bos_coster_heap_conv(std::vector<MultiexpData> data)
{
MULTIEXP_PERF(PERF_TIMER_START_UNIT(bos_coster, 1000000));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(setup, 1000000));
@ -142,15 +150,20 @@ rct::key bos_coster_heap_conv(std::vector<MultiexpData> &data)
return res;
}
rct::key bos_coster_heap_conv_robust(std::vector<MultiexpData> &data)
rct::key bos_coster_heap_conv_robust(std::vector<MultiexpData> data)
{
MULTIEXP_PERF(PERF_TIMER_START_UNIT(bos_coster, 1000000));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(setup, 1000000));
size_t points = data.size();
CHECK_AND_ASSERT_THROW_MES(points > 1, "Not enough points");
std::vector<size_t> heap(points);
std::vector<size_t> heap;
heap.reserve(points);
for (size_t n = 0; n < points; ++n)
heap[n] = n;
{
if (!(data[n].scalar == rct::zero()) && memcmp(&data[n].point, &ge_p3_identity, sizeof(ge_p3)))
heap.push_back(n);
}
points = heap.size();
auto Comp = [&](size_t e0, size_t e1) { return data[e0].scalar < data[e1].scalar; };
std::make_heap(heap.begin(), heap.end(), Comp);
@ -236,4 +249,118 @@ rct::key bos_coster_heap_conv_robust(std::vector<MultiexpData> &data)
return res;
}
rct::key straus(const std::vector<MultiexpData> &data, bool HiGi)
{
MULTIEXP_PERF(PERF_TIMER_UNIT(straus, 1000000));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(setup, 1000000));
static constexpr unsigned int c = 4;
static constexpr unsigned int mask = (1<<c)-1;
static std::vector<std::vector<ge_cached>> HiGi_multiples;
std::vector<std::vector<ge_cached>> local_multiples, &multiples = HiGi ? HiGi_multiples : local_multiples;
ge_cached cached;
ge_p1p1 p1;
ge_p3 p3;
std::vector<uint8_t> skip(data.size());
for (size_t i = 0; i < data.size(); ++i)
skip[i] = data[i].scalar == rct::zero() || !memcmp(&data[i].point, &ge_p3_identity, sizeof(ge_p3));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(multiples, 1000000));
multiples.resize(1<<c);
size_t offset = multiples[1].size();
multiples[1].resize(std::max(offset, data.size()));
for (size_t i = offset; i < data.size(); ++i)
ge_p3_to_cached(&multiples[1][i], &data[i].point);
for (size_t i=2;i<1<<c;++i)
multiples[i].resize(std::max(offset, data.size()));
for (size_t j=offset;j<data.size();++j)
{
for (size_t i=2;i<1<<c;++i)
{
ge_add(&p1, &data[j].point, &multiples[i-1][j]);
ge_p1p1_to_p3(&p3, &p1);
ge_p3_to_cached(&multiples[i][j], &p3);
}
}
MULTIEXP_PERF(PERF_TIMER_STOP(multiples));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(digits, 1000000));
std::vector<std::vector<uint8_t>> digits;
digits.resize(data.size());
for (size_t j = 0; j < data.size(); ++j)
{
digits[j].resize(256);
unsigned char bytes33[33];
memcpy(bytes33, data[j].scalar.bytes, 32);
bytes33[32] = 0;
#if 1
static_assert(c == 4, "optimized version needs c == 4");
const unsigned char *bytes = bytes33;
unsigned int i;
for (i = 0; i < 256; i += 8, bytes++)
{
digits[j][i] = bytes[0] & 0xf;
digits[j][i+1] = (bytes[0] >> 1) & 0xf;
digits[j][i+2] = (bytes[0] >> 2) & 0xf;
digits[j][i+3] = (bytes[0] >> 3) & 0xf;
digits[j][i+4] = ((bytes[0] >> 4) | (bytes[1]<<4)) & 0xf;
digits[j][i+5] = ((bytes[0] >> 5) | (bytes[1]<<3)) & 0xf;
digits[j][i+6] = ((bytes[0] >> 6) | (bytes[1]<<2)) & 0xf;
digits[j][i+7] = ((bytes[0] >> 7) | (bytes[1]<<1)) & 0xf;
}
#elif 1
for (size_t i = 0; i < 256; ++i)
digits[j][i] = ((bytes[i>>3] | (bytes[(i>>3)+1]<<8)) >> (i&7)) & mask;
#else
rct::key shifted = data[j].scalar;
for (size_t i = 0; i < 256; ++i)
{
digits[j][i] = shifted.bytes[0] & 0xf;
shifted = div2(shifted, (256-i)>>3);
}
#endif
}
MULTIEXP_PERF(PERF_TIMER_STOP(digits));
rct::key maxscalar = rct::zero();
for (size_t i = 0; i < data.size(); ++i)
if (maxscalar < data[i].scalar)
maxscalar = data[i].scalar;
size_t i = 0;
while (i < 256 && !(maxscalar < pow2(i)))
i += c;
MULTIEXP_PERF(PERF_TIMER_STOP(setup));
ge_p3 res_p3 = ge_p3_identity;
if (!(i < c))
goto skipfirst;
while (!(i < c))
{
for (size_t j = 0; j < c; ++j)
{
ge_p3_to_cached(&cached, &res_p3);
ge_add(&p1, &res_p3, &cached);
ge_p1p1_to_p3(&res_p3, &p1);
}
skipfirst:
i -= c;
for (size_t j = 0; j < data.size(); ++j)
{
if (skip[j])
continue;
int digit = digits[j][i];
if (digit)
{
ge_add(&p1, &res_p3, &multiples[digit][j]);
ge_p1p1_to_p3(&res_p3, &p1);
}
}
}
rct::key res;
ge_p3_tobytes(res.bytes, &res_p3);
return res;
}
}

5
src/ringct/multiexp.h
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@ -52,8 +52,9 @@ struct MultiexpData {
}
};
rct::key bos_coster_heap_conv(std::vector<MultiexpData> &data);
rct::key bos_coster_heap_conv_robust(std::vector<MultiexpData> &data);
rct::key bos_coster_heap_conv(std::vector<MultiexpData> data);
rct::key bos_coster_heap_conv_robust(std::vector<MultiexpData> data);
rct::key straus(const std::vector<MultiexpData> &data, bool HiGi = false);
}

1
tests/performance_tests/CMakeLists.txt
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@ -45,6 +45,7 @@ set(performance_tests_headers
range_proof.h
bulletproof.h
crypto_ops.h
multiexp.h
multi_tx_test_base.h
performance_tests.h
performance_utils.h

15
tests/performance_tests/main.cpp
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@ -56,6 +56,7 @@
#include "rct_mlsag.h"
#include "bulletproof.h"
#include "crypto_ops.h"
#include "multiexp.h"
namespace po = boost::program_options;
@ -196,6 +197,20 @@ int main(int argc, char** argv)
TEST_PERFORMANCE1(filter, test_crypto_ops, op_addKeys3);
TEST_PERFORMANCE1(filter, test_crypto_ops, op_addKeys3_2);
TEST_PERFORMANCE2(filter, verbose, test_multiexp, multiexp_bos_coster, 2);
TEST_PERFORMANCE2(filter, verbose, test_multiexp, multiexp_bos_coster, 8);
TEST_PERFORMANCE2(filter, verbose, test_multiexp, multiexp_bos_coster, 16);
TEST_PERFORMANCE2(filter, verbose, test_multiexp, multiexp_bos_coster, 256);
TEST_PERFORMANCE2(filter, verbose, test_multiexp, multiexp_bos_coster, 1024);
TEST_PERFORMANCE2(filter, verbose, test_multiexp, multiexp_bos_coster, 4096);
TEST_PERFORMANCE2(filter, verbose, test_multiexp, multiexp_straus, 2);
TEST_PERFORMANCE2(filter, verbose, test_multiexp, multiexp_straus, 8);
TEST_PERFORMANCE2(filter, verbose, test_multiexp, multiexp_straus, 16);
TEST_PERFORMANCE2(filter, verbose, test_multiexp, multiexp_straus, 256);
TEST_PERFORMANCE2(filter, verbose, test_multiexp, multiexp_straus, 1024);
TEST_PERFORMANCE2(filter, verbose, test_multiexp, multiexp_straus, 4096);
std::cout << "Tests finished. Elapsed time: " << timer.elapsed_ms() / 1000 << " sec" << std::endl;
return 0;

81
tests/performance_tests/multiexp.h
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@ -0,0 +1,81 @@
// Copyright (c) 2018, The Monero Project
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of
// conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
// of conditions and the following disclaimer in the documentation and/or other
// materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its contributors may be
// used to endorse or promote products derived from this software without specific
// prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers
#pragma once
#include <vector>
#include "ringct/rctOps.h"
#include "ringct/multiexp.h"
enum test_multiexp_algorithm
{
multiexp_bos_coster,
multiexp_straus,
};
template<test_multiexp_algorithm algorithm, size_t npoints>
class test_multiexp
{
public:
static const size_t loop_count = npoints >= 1024 ? 10 : npoints < 256 ? 1000 : 100;
bool init()
{
data.resize(npoints);
res = rct::identity();
for (size_t n = 0; n < npoints; ++n)
{
data[n].scalar = rct::skGen();
rct::key point = rct::scalarmultBase(rct::skGen());
if (ge_frombytes_vartime(&data[n].point, point.bytes))
return false;
rct::key kn = rct::scalarmultKey(point, data[n].scalar);
res = rct::addKeys(res, kn);
}
return true;
}
bool test()
{
switch (algorithm)
{
case multiexp_bos_coster:
return res == bos_coster_heap_conv_robust(data);
case multiexp_straus:
return res == straus(data, false);
default:
return false;
}
}
private:
std::vector<rct::MultiexpData> data;
rct::key res;
};
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