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author | Riccardo Spagni <ric@spagni.net> | 2015-12-30 12:28:03 +0200 |
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committer | Riccardo Spagni <ric@spagni.net> | 2015-12-30 12:28:03 +0200 |
commit | 7223eebbe71833e895fca95267cb243834dedf83 (patch) | |
tree | a5d48783316ff837e353c51a29b54f5324dd0bb1 /external/rapidjson/internal/biginteger.h | |
parent | Merge pull request #575 (diff) | |
parent | no longer need to pass the size to rapidjson (diff) | |
download | monero-7223eebbe71833e895fca95267cb243834dedf83.tar.xz |
Merge pull request #577
32a2633 no longer need to pass the size to rapidjson (Riccardo Spagni)
bd8e0fd add missing miniupnpc files, modify cmake to not build miniupnpc tests and to fix an issue with finding miniupnpcstrings (Riccardo Spagni)
7da9905 updated miniupnpc (Riccardo Spagni)
Diffstat (limited to 'external/rapidjson/internal/biginteger.h')
-rwxr-xr-x | external/rapidjson/internal/biginteger.h | 290 |
1 files changed, 290 insertions, 0 deletions
diff --git a/external/rapidjson/internal/biginteger.h b/external/rapidjson/internal/biginteger.h new file mode 100755 index 000000000..9d3e88c99 --- /dev/null +++ b/external/rapidjson/internal/biginteger.h @@ -0,0 +1,290 @@ +// Tencent is pleased to support the open source community by making RapidJSON available. +// +// Copyright (C) 2015 THL A29 Limited, a Tencent company, and Milo Yip. All rights reserved. +// +// Licensed under the MIT License (the "License"); you may not use this file except +// in compliance with the License. You may obtain a copy of the License at +// +// http://opensource.org/licenses/MIT +// +// Unless required by applicable law or agreed to in writing, software distributed +// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR +// CONDITIONS OF ANY KIND, either express or implied. See the License for the +// specific language governing permissions and limitations under the License. + +#ifndef RAPIDJSON_BIGINTEGER_H_ +#define RAPIDJSON_BIGINTEGER_H_ + +#include "../rapidjson.h" + +#if defined(_MSC_VER) && defined(_M_AMD64) +#include <intrin.h> // for _umul128 +#pragma intrinsic(_umul128) +#endif + +RAPIDJSON_NAMESPACE_BEGIN +namespace internal { + +class BigInteger { +public: + typedef uint64_t Type; + + BigInteger(const BigInteger& rhs) : count_(rhs.count_) { + std::memcpy(digits_, rhs.digits_, count_ * sizeof(Type)); + } + + explicit BigInteger(uint64_t u) : count_(1) { + digits_[0] = u; + } + + BigInteger(const char* decimals, size_t length) : count_(1) { + RAPIDJSON_ASSERT(length > 0); + digits_[0] = 0; + size_t i = 0; + const size_t kMaxDigitPerIteration = 19; // 2^64 = 18446744073709551616 > 10^19 + while (length >= kMaxDigitPerIteration) { + AppendDecimal64(decimals + i, decimals + i + kMaxDigitPerIteration); + length -= kMaxDigitPerIteration; + i += kMaxDigitPerIteration; + } + + if (length > 0) + AppendDecimal64(decimals + i, decimals + i + length); + } + + BigInteger& operator=(const BigInteger &rhs) + { + if (this != &rhs) { + count_ = rhs.count_; + std::memcpy(digits_, rhs.digits_, count_ * sizeof(Type)); + } + return *this; + } + + BigInteger& operator=(uint64_t u) { + digits_[0] = u; + count_ = 1; + return *this; + } + + BigInteger& operator+=(uint64_t u) { + Type backup = digits_[0]; + digits_[0] += u; + for (size_t i = 0; i < count_ - 1; i++) { + if (digits_[i] >= backup) + return *this; // no carry + backup = digits_[i + 1]; + digits_[i + 1] += 1; + } + + // Last carry + if (digits_[count_ - 1] < backup) + PushBack(1); + + return *this; + } + + BigInteger& operator*=(uint64_t u) { + if (u == 0) return *this = 0; + if (u == 1) return *this; + if (*this == 1) return *this = u; + + uint64_t k = 0; + for (size_t i = 0; i < count_; i++) { + uint64_t hi; + digits_[i] = MulAdd64(digits_[i], u, k, &hi); + k = hi; + } + + if (k > 0) + PushBack(k); + + return *this; + } + + BigInteger& operator*=(uint32_t u) { + if (u == 0) return *this = 0; + if (u == 1) return *this; + if (*this == 1) return *this = u; + + uint64_t k = 0; + for (size_t i = 0; i < count_; i++) { + const uint64_t c = digits_[i] >> 32; + const uint64_t d = digits_[i] & 0xFFFFFFFF; + const uint64_t uc = u * c; + const uint64_t ud = u * d; + const uint64_t p0 = ud + k; + const uint64_t p1 = uc + (p0 >> 32); + digits_[i] = (p0 & 0xFFFFFFFF) | (p1 << 32); + k = p1 >> 32; + } + + if (k > 0) + PushBack(k); + + return *this; + } + + BigInteger& operator<<=(size_t shift) { + if (IsZero() || shift == 0) return *this; + + size_t offset = shift / kTypeBit; + size_t interShift = shift % kTypeBit; + RAPIDJSON_ASSERT(count_ + offset <= kCapacity); + + if (interShift == 0) { + std::memmove(&digits_[count_ - 1 + offset], &digits_[count_ - 1], count_ * sizeof(Type)); + count_ += offset; + } + else { + digits_[count_] = 0; + for (size_t i = count_; i > 0; i--) + digits_[i + offset] = (digits_[i] << interShift) | (digits_[i - 1] >> (kTypeBit - interShift)); + digits_[offset] = digits_[0] << interShift; + count_ += offset; + if (digits_[count_]) + count_++; + } + + std::memset(digits_, 0, offset * sizeof(Type)); + + return *this; + } + + bool operator==(const BigInteger& rhs) const { + return count_ == rhs.count_ && std::memcmp(digits_, rhs.digits_, count_ * sizeof(Type)) == 0; + } + + bool operator==(const Type rhs) const { + return count_ == 1 && digits_[0] == rhs; + } + + BigInteger& MultiplyPow5(unsigned exp) { + static const uint32_t kPow5[12] = { + 5, + 5 * 5, + 5 * 5 * 5, + 5 * 5 * 5 * 5, + 5 * 5 * 5 * 5 * 5, + 5 * 5 * 5 * 5 * 5 * 5, + 5 * 5 * 5 * 5 * 5 * 5 * 5, + 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5, + 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5, + 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5, + 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5, + 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 + }; + if (exp == 0) return *this; + for (; exp >= 27; exp -= 27) *this *= RAPIDJSON_UINT64_C2(0X6765C793, 0XFA10079D); // 5^27 + for (; exp >= 13; exp -= 13) *this *= static_cast<uint32_t>(1220703125u); // 5^13 + if (exp > 0) *this *= kPow5[exp - 1]; + return *this; + } + + // Compute absolute difference of this and rhs. + // Assume this != rhs + bool Difference(const BigInteger& rhs, BigInteger* out) const { + int cmp = Compare(rhs); + RAPIDJSON_ASSERT(cmp != 0); + const BigInteger *a, *b; // Makes a > b + bool ret; + if (cmp < 0) { a = &rhs; b = this; ret = true; } + else { a = this; b = &rhs; ret = false; } + + Type borrow = 0; + for (size_t i = 0; i < a->count_; i++) { + Type d = a->digits_[i] - borrow; + if (i < b->count_) + d -= b->digits_[i]; + borrow = (d > a->digits_[i]) ? 1 : 0; + out->digits_[i] = d; + if (d != 0) + out->count_ = i + 1; + } + + return ret; + } + + int Compare(const BigInteger& rhs) const { + if (count_ != rhs.count_) + return count_ < rhs.count_ ? -1 : 1; + + for (size_t i = count_; i-- > 0;) + if (digits_[i] != rhs.digits_[i]) + return digits_[i] < rhs.digits_[i] ? -1 : 1; + + return 0; + } + + size_t GetCount() const { return count_; } + Type GetDigit(size_t index) const { RAPIDJSON_ASSERT(index < count_); return digits_[index]; } + bool IsZero() const { return count_ == 1 && digits_[0] == 0; } + +private: + void AppendDecimal64(const char* begin, const char* end) { + uint64_t u = ParseUint64(begin, end); + if (IsZero()) + *this = u; + else { + unsigned exp = static_cast<unsigned>(end - begin); + (MultiplyPow5(exp) <<= exp) += u; // *this = *this * 10^exp + u + } + } + + void PushBack(Type digit) { + RAPIDJSON_ASSERT(count_ < kCapacity); + digits_[count_++] = digit; + } + + static uint64_t ParseUint64(const char* begin, const char* end) { + uint64_t r = 0; + for (const char* p = begin; p != end; ++p) { + RAPIDJSON_ASSERT(*p >= '0' && *p <= '9'); + r = r * 10u + static_cast<unsigned>(*p - '0'); + } + return r; + } + + // Assume a * b + k < 2^128 + static uint64_t MulAdd64(uint64_t a, uint64_t b, uint64_t k, uint64_t* outHigh) { +#if defined(_MSC_VER) && defined(_M_AMD64) + uint64_t low = _umul128(a, b, outHigh) + k; + if (low < k) + (*outHigh)++; + return low; +#elif (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)) && defined(__x86_64__) + __extension__ typedef unsigned __int128 uint128; + uint128 p = static_cast<uint128>(a) * static_cast<uint128>(b); + p += k; + *outHigh = static_cast<uint64_t>(p >> 64); + return static_cast<uint64_t>(p); +#else + const uint64_t a0 = a & 0xFFFFFFFF, a1 = a >> 32, b0 = b & 0xFFFFFFFF, b1 = b >> 32; + uint64_t x0 = a0 * b0, x1 = a0 * b1, x2 = a1 * b0, x3 = a1 * b1; + x1 += (x0 >> 32); // can't give carry + x1 += x2; + if (x1 < x2) + x3 += (static_cast<uint64_t>(1) << 32); + uint64_t lo = (x1 << 32) + (x0 & 0xFFFFFFFF); + uint64_t hi = x3 + (x1 >> 32); + + lo += k; + if (lo < k) + hi++; + *outHigh = hi; + return lo; +#endif + } + + static const size_t kBitCount = 3328; // 64bit * 54 > 10^1000 + static const size_t kCapacity = kBitCount / sizeof(Type); + static const size_t kTypeBit = sizeof(Type) * 8; + + Type digits_[kCapacity]; + size_t count_; +}; + +} // namespace internal +RAPIDJSON_NAMESPACE_END + +#endif // RAPIDJSON_BIGINTEGER_H_ |