?????????? ????????? - ??????????????? - /usr/include/boost/json/detail/ryu/detail/d2s.hpp
???????
// Copyright 2018 Ulf Adams // // The contents of this file may be used under the terms of the Apache License, // Version 2.0. // // (See accompanying file LICENSE-Apache or copy at // http://www.apache.org/licenses/LICENSE-2.0) // // Alternatively, the contents of this file may be used under the terms of // the Boost Software License, Version 1.0. // (See accompanying file LICENSE-Boost or copy at // https://www.boost.org/LICENSE_1_0.txt) // // Unless required by applicable law or agreed to in writing, this software // is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY // KIND, either express or implied. /* This is a derivative work */ #ifndef BOOST_JSON_DETAIL_RYU_DETAIL_D2S_HPP #define BOOST_JSON_DETAIL_RYU_DETAIL_D2S_HPP #include <boost/json/detail/config.hpp> #include <boost/json/detail/ryu/detail/common.hpp> // Only include the full table if we're not optimizing for size. #if !defined(BOOST_JSON_RYU_OPTIMIZE_SIZE) #include <boost/json/detail/ryu/detail/d2s_full_table.hpp> #endif #if defined(BOOST_JSON_RYU_HAS_UINT128) typedef __uint128_t uint128_t; #else #include <boost/json/detail/ryu/detail/d2s_intrinsics.hpp> #endif BOOST_JSON_NS_BEGIN namespace detail { namespace ryu { namespace detail { constexpr int DOUBLE_POW5_INV_BITCOUNT = 122; constexpr int DOUBLE_POW5_BITCOUNT = 121; #if defined(BOOST_JSON_RYU_OPTIMIZE_SIZE) constexpr int POW5_TABLE_SIZE = 26; inline std::uint64_t const (&DOUBLE_POW5_TABLE() noexcept)[POW5_TABLE_SIZE] { static constexpr std::uint64_t arr[26] = { 1ull, 5ull, 25ull, 125ull, 625ull, 3125ull, 15625ull, 78125ull, 390625ull, 1953125ull, 9765625ull, 48828125ull, 244140625ull, 1220703125ull, 6103515625ull, 30517578125ull, 152587890625ull, 762939453125ull, 3814697265625ull, 19073486328125ull, 95367431640625ull, 476837158203125ull, 2384185791015625ull, 11920928955078125ull, 59604644775390625ull, 298023223876953125ull //, 1490116119384765625ull }; return arr; } inline std::uint64_t const (&DOUBLE_POW5_SPLIT2() noexcept)[13][2] { static constexpr std::uint64_t arr[13][2] = { { 0u, 72057594037927936u }, { 10376293541461622784u, 93132257461547851u }, { 15052517733678820785u, 120370621524202240u }, { 6258995034005762182u, 77787690973264271u }, { 14893927168346708332u, 100538234169297439u }, { 4272820386026678563u, 129942622070561240u }, { 7330497575943398595u, 83973451344588609u }, { 18377130505971182927u, 108533142064701048u }, { 10038208235822497557u, 140275798336537794u }, { 7017903361312433648u, 90651109995611182u }, { 6366496589810271835u, 117163813585596168u }, { 9264989777501460624u, 75715339914673581u }, { 17074144231291089770u, 97859783203563123u }}; return arr; } // Unfortunately, the results are sometimes off by one. We use an additional // lookup table to store those cases and adjust the result. inline std::uint32_t const (&POW5_OFFSETS() noexcept)[13] { static constexpr std::uint32_t arr[13] = { 0x00000000, 0x00000000, 0x00000000, 0x033c55be, 0x03db77d8, 0x0265ffb2, 0x00000800, 0x01a8ff56, 0x00000000, 0x0037a200, 0x00004000, 0x03fffffc, 0x00003ffe}; return arr; } inline std::uint64_t const (&DOUBLE_POW5_INV_SPLIT2() noexcept)[13][2] { static constexpr std::uint64_t arr[13][2] = { { 1u, 288230376151711744u }, { 7661987648932456967u, 223007451985306231u }, { 12652048002903177473u, 172543658669764094u }, { 5522544058086115566u, 266998379490113760u }, { 3181575136763469022u, 206579990246952687u }, { 4551508647133041040u, 159833525776178802u }, { 1116074521063664381u, 247330401473104534u }, { 17400360011128145022u, 191362629322552438u }, { 9297997190148906106u, 148059663038321393u }, { 11720143854957885429u, 229111231347799689u }, { 15401709288678291155u, 177266229209635622u }, { 3003071137298187333u, 274306203439684434u }, { 17516772882021341108u, 212234145163966538u }}; return arr; } inline std::uint32_t const (&POW5_INV_OFFSETS() noexcept)[20] { static constexpr std::uint32_t arr[20] = { 0x51505404, 0x55054514, 0x45555545, 0x05511411, 0x00505010, 0x00000004, 0x00000000, 0x00000000, 0x55555040, 0x00505051, 0x00050040, 0x55554000, 0x51659559, 0x00001000, 0x15000010, 0x55455555, 0x41404051, 0x00001010, 0x00000014, 0x00000000}; return arr; } #if defined(BOOST_JSON_RYU_HAS_UINT128) // Computes 5^i in the form required by Ryu, and stores it in the given pointer. inline void double_computePow5( const std::uint32_t i, std::uint64_t* const result) { const std::uint32_t base = i / POW5_TABLE_SIZE; const std::uint32_t base2 = base * POW5_TABLE_SIZE; const std::uint32_t offset = i - base2; const std::uint64_t* const mul = DOUBLE_POW5_SPLIT2()[base]; if (offset == 0) { result[0] = mul[0]; result[1] = mul[1]; return; } const std::uint64_t m = DOUBLE_POW5_TABLE()[offset]; const uint128_t b0 = ((uint128_t)m) * mul[0]; const uint128_t b2 = ((uint128_t)m) * mul[1]; const std::uint32_t delta = pow5bits(i) - pow5bits(base2); const uint128_t shiftedSum = (b0 >> delta) + (b2 << (64 - delta)) + ((POW5_OFFSETS()[base] >> offset) & 1); result[0] = (std::uint64_t)shiftedSum; result[1] = (std::uint64_t)(shiftedSum >> 64); } // Computes 5^-i in the form required by Ryu, and stores it in the given pointer. inline void double_computeInvPow5( const std::uint32_t i, std::uint64_t* const result) { const std::uint32_t base = (i + POW5_TABLE_SIZE - 1) / POW5_TABLE_SIZE; const std::uint32_t base2 = base * POW5_TABLE_SIZE; const std::uint32_t offset = base2 - i; const std::uint64_t* const mul = DOUBLE_POW5_INV_SPLIT2()[base]; // 1/5^base2 if (offset == 0) { result[0] = mul[0]; result[1] = mul[1]; return; } const std::uint64_t m = DOUBLE_POW5_TABLE()[offset]; // 5^offset const uint128_t b0 = ((uint128_t)m) * (mul[0] - 1); const uint128_t b2 = ((uint128_t)m) * mul[1]; // 1/5^base2 * 5^offset = 1/5^(base2-offset) = 1/5^i const std::uint32_t delta = pow5bits(base2) - pow5bits(i); const uint128_t shiftedSum = ((b0 >> delta) + (b2 << (64 - delta))) + 1 + ((POW5_INV_OFFSETS()[i / 16] >> ((i % 16) << 1)) & 3); result[0] = (std::uint64_t)shiftedSum; result[1] = (std::uint64_t)(shiftedSum >> 64); } #else // defined(BOOST_JSON_RYU_HAS_UINT128) // Computes 5^i in the form required by Ryu, and stores it in the given pointer. inline void double_computePow5( const std::uint32_t i, std::uint64_t* const result) { const std::uint32_t base = i / POW5_TABLE_SIZE; const std::uint32_t base2 = base * POW5_TABLE_SIZE; const std::uint32_t offset = i - base2; const std::uint64_t* const mul = DOUBLE_POW5_SPLIT2()[base]; if (offset == 0) { result[0] = mul[0]; result[1] = mul[1]; return; } std::uint64_t const m = DOUBLE_POW5_TABLE()[offset]; std::uint64_t high1; std::uint64_t const low1 = umul128(m, mul[1], &high1); std::uint64_t high0; std::uint64_t const low0 = umul128(m, mul[0], &high0); std::uint64_t const sum = high0 + low1; if (sum < high0) ++high1; // overflow into high1 // high1 | sum | low0 std::uint32_t const delta = pow5bits(i) - pow5bits(base2); result[0] = shiftright128(low0, sum, delta) + ((POW5_OFFSETS()[base] >> offset) & 1); result[1] = shiftright128(sum, high1, delta); } // Computes 5^-i in the form required by Ryu, and stores it in the given pointer. inline void double_computeInvPow5( const std::uint32_t i, std::uint64_t* const result) { const std::uint32_t base = (i + POW5_TABLE_SIZE - 1) / POW5_TABLE_SIZE; const std::uint32_t base2 = base * POW5_TABLE_SIZE; const std::uint32_t offset = base2 - i; const std::uint64_t* const mul = DOUBLE_POW5_INV_SPLIT2()[base]; // 1/5^base2 if (offset == 0) { result[0] = mul[0]; result[1] = mul[1]; return; } std::uint64_t const m = DOUBLE_POW5_TABLE()[offset]; std::uint64_t high1; std::uint64_t const low1 = umul128(m, mul[1], &high1); std::uint64_t high0; std::uint64_t const low0 = umul128(m, mul[0] - 1, &high0); std::uint64_t const sum = high0 + low1; if (sum < high0) ++high1; // overflow into high1 // high1 | sum | low0 std::uint32_t const delta = pow5bits(base2) - pow5bits(i); result[0] = shiftright128(low0, sum, delta) + 1 + ((POW5_INV_OFFSETS()[i / 16] >> ((i % 16) << 1)) & 3); result[1] = shiftright128(sum, high1, delta); } #endif // defined(BOOST_JSON_RYU_HAS_UINT128) #endif // defined(BOOST_JSON_RYU_OPTIMIZE_SIZE) } // detail } // ryu } // detail BOOST_JSON_NS_END #endif
| ver. 1.6 |
Github
|
.
| PHP 8.2.30 | ??????????? ?????????: 0.01 |
proxy
|
phpinfo
|
???????????