multiexp: cut down on memory allocations

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moneromooo-monero 2018-05-26 23:19:21 +01:00
parent 1b867e7f40
commit 1ed0ed4de4
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@ -394,37 +394,35 @@ rct::key straus(const std::vector<MultiexpData> &data, const std::shared_ptr<str
#endif
MULTIEXP_PERF(PERF_TIMER_START_UNIT(digits, 1000000));
std::vector<std::vector<uint8_t>> digits;
digits.resize(data.size());
std::unique_ptr<uint8_t[]> digits{new uint8_t[256 * 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;
const unsigned char *bytes = bytes33;
#if 1
static_assert(STRAUS_C == 4, "optimized version needs STRAUS_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;
digits[j*256+i] = bytes[0] & 0xf;
digits[j*256+i+1] = (bytes[0] >> 1) & 0xf;
digits[j*256+i+2] = (bytes[0] >> 2) & 0xf;
digits[j*256+i+3] = (bytes[0] >> 3) & 0xf;
digits[j*256+i+4] = ((bytes[0] >> 4) | (bytes[1]<<4)) & 0xf;
digits[j*256+i+5] = ((bytes[0] >> 5) | (bytes[1]<<3)) & 0xf;
digits[j*256+i+6] = ((bytes[0] >> 6) | (bytes[1]<<2)) & 0xf;
digits[j*256+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;
digits[j*256+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;
digits[j*256+i] = shifted.bytes[0] & 0xf;
shifted = div2(shifted, (256-i)>>3);
}
#endif
@ -470,7 +468,7 @@ skipfirst:
if (skip[j])
continue;
#endif
const uint8_t digit = digits[j][i];
const uint8_t digit = digits[j*256+i];
if (digit)
{
ge_add(&p1, &band_p3, &CACHE_OFFSET(local_cache, j, digit));