multiexp: some minor speedups

This commit is contained in:
moneromooo-monero 2018-10-22 11:56:45 +00:00
parent a6d2e246f3
commit 74fb3d882c
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@ -473,10 +473,7 @@ rct::key straus(const std::vector<MultiexpData> &data, const std::shared_ptr<str
#endif
for (size_t j = 0; j < data.size(); ++j)
{
unsigned char bytes33[33];
memcpy(bytes33, data[j].scalar.bytes, 32);
bytes33[32] = 0;
const unsigned char *bytes = bytes33;
const unsigned char *bytes = data[j].scalar.bytes;
#if STRAUS_C==4
unsigned int i;
for (i = 0; i < 64; i += 2, bytes++)
@ -485,6 +482,10 @@ rct::key straus(const std::vector<MultiexpData> &data, const std::shared_ptr<str
digits[j*64+i+1] = bytes[0] >> 4;
}
#elif 1
unsigned char bytes33[33];
memcpy(bytes33, data[j].scalar.bytes, 32);
bytes33[32] = 0;
bytes = bytes33;
for (size_t i = 0; i < 256; ++i)
digits[j*256+i] = ((bytes[i>>3] | (bytes[(i>>3)+1]<<8)) >> (i&7)) & mask;
#else
@ -615,7 +616,9 @@ rct::key pippenger(const std::vector<MultiexpData> &data, const std::shared_ptr<
CHECK_AND_ASSERT_THROW_MES(c <= 9, "c is too large");
ge_p3 result = ge_p3_identity;
bool result_init = false;
std::unique_ptr<ge_p3[]> buckets{new ge_p3[1<<c]};
bool buckets_init[1<<9];
std::shared_ptr<pippenger_cached_data> local_cache = cache == NULL ? pippenger_init_cache(data) : cache;
std::shared_ptr<pippenger_cached_data> local_cache_2 = data.size() > cache_size ? pippenger_init_cache(data, cache_size) : NULL;
@ -632,7 +635,7 @@ rct::key pippenger(const std::vector<MultiexpData> &data, const std::shared_ptr<
for (size_t k = groups; k-- > 0; )
{
if (!ge_p3_is_point_at_infinity(&result))
if (result_init)
{
ge_p2 p2;
ge_p3_to_p2(&p2, &result);
@ -646,8 +649,7 @@ rct::key pippenger(const std::vector<MultiexpData> &data, const std::shared_ptr<
ge_p1p1_to_p2(&p2, &p1);
}
}
for (size_t i = 0; i < (1u<<c); ++i)
buckets[i] = ge_p3_identity;
memset(buckets_init, 0, 1u<<c);
// partition scalars into buckets
for (size_t i = 0; i < data.size(); ++i)
@ -659,7 +661,7 @@ rct::key pippenger(const std::vector<MultiexpData> &data, const std::shared_ptr<
if (bucket == 0)
continue;
CHECK_AND_ASSERT_THROW_MES(bucket < (1u<<c), "bucket overflow");
if (!ge_p3_is_point_at_infinity(&buckets[bucket]))
if (buckets_init[bucket])
{
if (i < cache_size)
add(buckets[bucket], local_cache->cached[i]);
@ -667,17 +669,37 @@ rct::key pippenger(const std::vector<MultiexpData> &data, const std::shared_ptr<
add(buckets[bucket], local_cache_2->cached[i - cache_size]);
}
else
{
buckets[bucket] = data[i].point;
buckets_init[bucket] = true;
}
}
// sum the buckets
ge_p3 pail = ge_p3_identity;
ge_p3 pail;
bool pail_init = false;
for (size_t i = (1<<c)-1; i > 0; --i)
{
if (!ge_p3_is_point_at_infinity(&buckets[i]))
add(pail, buckets[i]);
if (!ge_p3_is_point_at_infinity(&pail))
add(result, pail);
if (buckets_init[i])
{
if (pail_init)
add(pail, buckets[i]);
else
{
pail = buckets[i];
pail_init = true;
}
}
if (pail_init)
{
if (result_init)
add(result, pail);
else
{
result = pail;
result_init = true;
}
}
}
}