/* * Copyright 2010-2017 Branimir Karadzic. All rights reserved. * License: https://github.com/bkaradzic/bx#license-bsd-2-clause */ #include #include #include #include #include namespace bx { // https://github.com/miloyip/dtoa-benchmark // // Copyright (C) 2014 Milo Yip // // Permission is hereby granted, free of charge, to any person obtaining a copy // of this software and associated documentation files (the "Software"), to deal // in the Software without restriction, including without limitation the rights // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell // copies of the Software, and to permit persons to whom the Software is // furnished to do so, subject to the following conditions: // // The above copyright notice and this permission notice shall be included in // all copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN // THE SOFTWARE. // struct DiyFp { DiyFp() { } DiyFp(uint64_t _f, int32_t _e) : f(_f) , e(_e) { } DiyFp(double d) { union { double d; uint64_t u64; } u = { d }; int32_t biased_e = (u.u64 & kDpExponentMask) >> kDpSignificandSize; uint64_t significand = (u.u64 & kDpSignificandMask); if (biased_e != 0) { f = significand + kDpHiddenBit; e = biased_e - kDpExponentBias; } else { f = significand; e = kDpMinExponent + 1; } } DiyFp operator-(const DiyFp& rhs) const { BX_CHECK(e == rhs.e, ""); BX_CHECK(f >= rhs.f, ""); return DiyFp(f - rhs.f, e); } DiyFp operator*(const DiyFp& rhs) const { const uint64_t M32 = 0xFFFFFFFF; const uint64_t a = f >> 32; const uint64_t b = f & M32; const uint64_t c = rhs.f >> 32; const uint64_t d = rhs.f & M32; const uint64_t ac = a * c; const uint64_t bc = b * c; const uint64_t ad = a * d; const uint64_t bd = b * d; uint64_t tmp = (bd >> 32) + (ad & M32) + (bc & M32); tmp += 1U << 31; /// mult_round return DiyFp(ac + (ad >> 32) + (bc >> 32) + (tmp >> 32), e + rhs.e + 64); } DiyFp Normalize() const { uint32_t s = uint64_cntlz(f); return DiyFp(f << s, e - s); } DiyFp NormalizeBoundary() const { uint32_t index = uint64_cntlz(f); return DiyFp (f << index, e - index); } void NormalizedBoundaries(DiyFp* minus, DiyFp* plus) const { DiyFp pl = DiyFp((f << 1) + 1, e - 1).NormalizeBoundary(); DiyFp mi = (f == kDpHiddenBit) ? DiyFp((f << 2) - 1, e - 2) : DiyFp((f << 1) - 1, e - 1); mi.f <<= mi.e - pl.e; mi.e = pl.e; *plus = pl; *minus = mi; } #define UINT64_C2(h, l) ((static_cast(h) << 32) | static_cast(l)) static const int32_t kDiySignificandSize = 64; static const int32_t kDpSignificandSize = 52; static const int32_t kDpExponentBias = 0x3FF + kDpSignificandSize; static const int32_t kDpMinExponent = -kDpExponentBias; static const uint64_t kDpExponentMask = UINT64_C2(0x7FF00000, 0x00000000); static const uint64_t kDpSignificandMask = UINT64_C2(0x000FFFFF, 0xFFFFFFFF); static const uint64_t kDpHiddenBit = UINT64_C2(0x00100000, 0x00000000); uint64_t f; int32_t e; }; // 10^-348, 10^-340, ..., 10^340 static const uint64_t s_kCachedPowers_F[] = { UINT64_C2(0xfa8fd5a0, 0x081c0288), UINT64_C2(0xbaaee17f, 0xa23ebf76), UINT64_C2(0x8b16fb20, 0x3055ac76), UINT64_C2(0xcf42894a, 0x5dce35ea), UINT64_C2(0x9a6bb0aa, 0x55653b2d), UINT64_C2(0xe61acf03, 0x3d1a45df), UINT64_C2(0xab70fe17, 0xc79ac6ca), UINT64_C2(0xff77b1fc, 0xbebcdc4f), UINT64_C2(0xbe5691ef, 0x416bd60c), UINT64_C2(0x8dd01fad, 0x907ffc3c), UINT64_C2(0xd3515c28, 0x31559a83), UINT64_C2(0x9d71ac8f, 0xada6c9b5), UINT64_C2(0xea9c2277, 0x23ee8bcb), UINT64_C2(0xaecc4991, 0x4078536d), UINT64_C2(0x823c1279, 0x5db6ce57), UINT64_C2(0xc2109436, 0x4dfb5637), UINT64_C2(0x9096ea6f, 0x3848984f), UINT64_C2(0xd77485cb, 0x25823ac7), UINT64_C2(0xa086cfcd, 0x97bf97f4), UINT64_C2(0xef340a98, 0x172aace5), UINT64_C2(0xb23867fb, 0x2a35b28e), UINT64_C2(0x84c8d4df, 0xd2c63f3b), UINT64_C2(0xc5dd4427, 0x1ad3cdba), UINT64_C2(0x936b9fce, 0xbb25c996), UINT64_C2(0xdbac6c24, 0x7d62a584), UINT64_C2(0xa3ab6658, 0x0d5fdaf6), UINT64_C2(0xf3e2f893, 0xdec3f126), UINT64_C2(0xb5b5ada8, 0xaaff80b8), UINT64_C2(0x87625f05, 0x6c7c4a8b), UINT64_C2(0xc9bcff60, 0x34c13053), UINT64_C2(0x964e858c, 0x91ba2655), UINT64_C2(0xdff97724, 0x70297ebd), UINT64_C2(0xa6dfbd9f, 0xb8e5b88f), UINT64_C2(0xf8a95fcf, 0x88747d94), UINT64_C2(0xb9447093, 0x8fa89bcf), UINT64_C2(0x8a08f0f8, 0xbf0f156b), UINT64_C2(0xcdb02555, 0x653131b6), UINT64_C2(0x993fe2c6, 0xd07b7fac), UINT64_C2(0xe45c10c4, 0x2a2b3b06), UINT64_C2(0xaa242499, 0x697392d3), UINT64_C2(0xfd87b5f2, 0x8300ca0e), UINT64_C2(0xbce50864, 0x92111aeb), UINT64_C2(0x8cbccc09, 0x6f5088cc), UINT64_C2(0xd1b71758, 0xe219652c), UINT64_C2(0x9c400000, 0x00000000), UINT64_C2(0xe8d4a510, 0x00000000), UINT64_C2(0xad78ebc5, 0xac620000), UINT64_C2(0x813f3978, 0xf8940984), UINT64_C2(0xc097ce7b, 0xc90715b3), UINT64_C2(0x8f7e32ce, 0x7bea5c70), UINT64_C2(0xd5d238a4, 0xabe98068), UINT64_C2(0x9f4f2726, 0x179a2245), UINT64_C2(0xed63a231, 0xd4c4fb27), UINT64_C2(0xb0de6538, 0x8cc8ada8), UINT64_C2(0x83c7088e, 0x1aab65db), UINT64_C2(0xc45d1df9, 0x42711d9a), UINT64_C2(0x924d692c, 0xa61be758), UINT64_C2(0xda01ee64, 0x1a708dea), UINT64_C2(0xa26da399, 0x9aef774a), UINT64_C2(0xf209787b, 0xb47d6b85), UINT64_C2(0xb454e4a1, 0x79dd1877), UINT64_C2(0x865b8692, 0x5b9bc5c2), UINT64_C2(0xc83553c5, 0xc8965d3d), UINT64_C2(0x952ab45c, 0xfa97a0b3), UINT64_C2(0xde469fbd, 0x99a05fe3), UINT64_C2(0xa59bc234, 0xdb398c25), UINT64_C2(0xf6c69a72, 0xa3989f5c), UINT64_C2(0xb7dcbf53, 0x54e9bece), UINT64_C2(0x88fcf317, 0xf22241e2), UINT64_C2(0xcc20ce9b, 0xd35c78a5), UINT64_C2(0x98165af3, 0x7b2153df), UINT64_C2(0xe2a0b5dc, 0x971f303a), UINT64_C2(0xa8d9d153, 0x5ce3b396), UINT64_C2(0xfb9b7cd9, 0xa4a7443c), UINT64_C2(0xbb764c4c, 0xa7a44410), UINT64_C2(0x8bab8eef, 0xb6409c1a), UINT64_C2(0xd01fef10, 0xa657842c), UINT64_C2(0x9b10a4e5, 0xe9913129), UINT64_C2(0xe7109bfb, 0xa19c0c9d), UINT64_C2(0xac2820d9, 0x623bf429), UINT64_C2(0x80444b5e, 0x7aa7cf85), UINT64_C2(0xbf21e440, 0x03acdd2d), UINT64_C2(0x8e679c2f, 0x5e44ff8f), UINT64_C2(0xd433179d, 0x9c8cb841), UINT64_C2(0x9e19db92, 0xb4e31ba9), UINT64_C2(0xeb96bf6e, 0xbadf77d9), UINT64_C2(0xaf87023b, 0x9bf0ee6b) }; static const int16_t s_kCachedPowers_E[] = { -1220, -1193, -1166, -1140, -1113, -1087, -1060, -1034, -1007, -980, -954, -927, -901, -874, -847, -821, -794, -768, -741, -715, -688, -661, -635, -608, -582, -555, -529, -502, -475, -449, -422, -396, -369, -343, -316, -289, -263, -236, -210, -183, -157, -130, -103, -77, -50, -24, 3, 30, 56, 83, 109, 136, 162, 189, 216, 242, 269, 295, 322, 348, 375, 402, 428, 455, 481, 508, 534, 561, 588, 614, 641, 667, 694, 720, 747, 774, 800, 827, 853, 880, 907, 933, 960, 986, 1013, 1039, 1066 }; static const char s_cDigitsLut[200] = { '0', '0', '0', '1', '0', '2', '0', '3', '0', '4', '0', '5', '0', '6', '0', '7', '0', '8', '0', '9', '1', '0', '1', '1', '1', '2', '1', '3', '1', '4', '1', '5', '1', '6', '1', '7', '1', '8', '1', '9', '2', '0', '2', '1', '2', '2', '2', '3', '2', '4', '2', '5', '2', '6', '2', '7', '2', '8', '2', '9', '3', '0', '3', '1', '3', '2', '3', '3', '3', '4', '3', '5', '3', '6', '3', '7', '3', '8', '3', '9', '4', '0', '4', '1', '4', '2', '4', '3', '4', '4', '4', '5', '4', '6', '4', '7', '4', '8', '4', '9', '5', '0', '5', '1', '5', '2', '5', '3', '5', '4', '5', '5', '5', '6', '5', '7', '5', '8', '5', '9', '6', '0', '6', '1', '6', '2', '6', '3', '6', '4', '6', '5', '6', '6', '6', '7', '6', '8', '6', '9', '7', '0', '7', '1', '7', '2', '7', '3', '7', '4', '7', '5', '7', '6', '7', '7', '7', '8', '7', '9', '8', '0', '8', '1', '8', '2', '8', '3', '8', '4', '8', '5', '8', '6', '8', '7', '8', '8', '8', '9', '9', '0', '9', '1', '9', '2', '9', '3', '9', '4', '9', '5', '9', '6', '9', '7', '9', '8', '9', '9' }; static const uint32_t s_kPow10[] = { 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000 }; DiyFp GetCachedPower(int32_t e, int32_t* K) { double dk = (-61 - e) * 0.30102999566398114 + 347; // dk must be positive, so can do ceiling in positive int32_t k = static_cast(dk); if (k != dk) { k++; } uint32_t index = static_cast((k >> 3) + 1); *K = -(-348 + static_cast(index << 3)); // decimal exponent no need lookup table BX_CHECK(index < sizeof(s_kCachedPowers_F) / sizeof(s_kCachedPowers_F[0])); return DiyFp(s_kCachedPowers_F[index], s_kCachedPowers_E[index]); } void GrisuRound(char* buffer, int32_t len, uint64_t delta, uint64_t rest, uint64_t ten_kappa, uint64_t wp_w) { while (rest < wp_w && delta - rest >= ten_kappa && (rest + ten_kappa < wp_w || wp_w - rest > rest + ten_kappa - wp_w)) { buffer[len - 1]--; rest += ten_kappa; } } uint32_t CountDecimalDigit32(uint32_t n) { // Simple pure C++ implementation was faster than __builtin_clz version in this situation. if (n < 10) return 1; if (n < 100) return 2; if (n < 1000) return 3; if (n < 10000) return 4; if (n < 100000) return 5; if (n < 1000000) return 6; if (n < 10000000) return 7; if (n < 100000000) return 8; if (n < 1000000000) return 9; return 10; } void DigitGen(const DiyFp& W, const DiyFp& Mp, uint64_t delta, char* buffer, int32_t* len, int32_t* K) { const DiyFp one(uint64_t(1) << -Mp.e, Mp.e); const DiyFp wp_w = Mp - W; uint32_t p1 = static_cast(Mp.f >> -one.e); uint64_t p2 = Mp.f & (one.f - 1); int32_t kappa = static_cast(CountDecimalDigit32(p1)); *len = 0; while (kappa > 0) { uint32_t d; switch (kappa) { case 10: d = p1 / 1000000000; p1 %= 1000000000; break; case 9: d = p1 / 100000000; p1 %= 100000000; break; case 8: d = p1 / 10000000; p1 %= 10000000; break; case 7: d = p1 / 1000000; p1 %= 1000000; break; case 6: d = p1 / 100000; p1 %= 100000; break; case 5: d = p1 / 10000; p1 %= 10000; break; case 4: d = p1 / 1000; p1 %= 1000; break; case 3: d = p1 / 100; p1 %= 100; break; case 2: d = p1 / 10; p1 %= 10; break; case 1: d = p1; p1 = 0; break; default: d = 0; break; } if (d || *len) { buffer[(*len)++] = '0' + static_cast(d); } kappa--; uint64_t tmp = (static_cast(p1) << -one.e) + p2; if (tmp <= delta) { *K += kappa; GrisuRound(buffer, *len, delta, tmp, static_cast(s_kPow10[kappa]) << -one.e, wp_w.f); return; } } // kappa = 0 for (;;) { p2 *= 10; delta *= 10; char d = static_cast(p2 >> -one.e); if (d || *len) { buffer[(*len)++] = '0' + d; } p2 &= one.f - 1; kappa--; if (p2 < delta) { *K += kappa; GrisuRound(buffer, *len, delta, p2, one.f, wp_w.f * s_kPow10[-kappa]); return; } } } void Grisu2(double value, char* buffer, int32_t* length, int32_t* K) { const DiyFp v(value); DiyFp w_m, w_p; v.NormalizedBoundaries(&w_m, &w_p); const DiyFp c_mk = GetCachedPower(w_p.e, K); const DiyFp W = v.Normalize() * c_mk; DiyFp Wp = w_p * c_mk; DiyFp Wm = w_m * c_mk; Wm.f++; Wp.f--; DigitGen(W, Wp, Wp.f - Wm.f, buffer, length, K); } int32_t WriteExponent(int32_t K, char* buffer) { const char* ptr = buffer; if (K < 0) { *buffer++ = '-'; K = -K; } if (K >= 100) { *buffer++ = '0' + static_cast(K / 100); K %= 100; const char* d = s_cDigitsLut + K * 2; *buffer++ = d[0]; *buffer++ = d[1]; } else if (K >= 10) { const char* d = s_cDigitsLut + K * 2; *buffer++ = d[0]; *buffer++ = d[1]; } else { *buffer++ = '0' + static_cast(K); } *buffer = '\0'; return int32_t(buffer - ptr); } int32_t Prettify(char* buffer, int32_t length, int32_t k) { const int32_t kk = length + k; // 10^(kk-1) <= v < 10^kk if (length <= kk && kk <= 21) { // 1234e7 -> 12340000000 for (int32_t i = length; i < kk; i++) { buffer[i] = '0'; } buffer[kk] = '.'; buffer[kk + 1] = '0'; buffer[kk + 2] = '\0'; return kk + 2; } if (0 < kk && kk <= 21) { // 1234e-2 -> 12.34 memMove(&buffer[kk + 1], &buffer[kk], length - kk); buffer[kk] = '.'; buffer[length + 1] = '\0'; return length + 1; } if (-6 < kk && kk <= 0) { // 1234e-6 -> 0.001234 const int32_t offset = 2 - kk; memMove(&buffer[offset], &buffer[0], length); buffer[0] = '0'; buffer[1] = '.'; for (int32_t i = 2; i < offset; i++) { buffer[i] = '0'; } buffer[length + offset] = '\0'; return length + offset; } if (length == 1) { // 1e30 buffer[1] = 'e'; int32_t exp = WriteExponent(kk - 1, &buffer[2]); return 2 + exp; } // 1234e30 -> 1.234e33 memMove(&buffer[2], &buffer[1], length - 1); buffer[1] = '.'; buffer[length + 1] = 'e'; int32_t exp = WriteExponent(kk - 1, &buffer[length + 2]); return length + 2 + exp; } int32_t toString(char* _dst, int32_t _max, double _value) { int32_t sign = 0 != (doubleToBits(_value) & (UINT64_C(1)<<63) ) ? 1 : 0; if (1 == sign) { *_dst++ = '-'; --_max; _value = -_value; } if (isNan(_value) ) { return (int32_t)strlncpy(_dst, _max, "nan") + sign; } else if (isInfinite(_value) ) { return (int32_t)strlncpy(_dst, _max, "inf") + sign; } int32_t len; if (0.0 == _value) { len = (int32_t)strlncpy(_dst, _max, "0.0"); } else { int32_t kk; Grisu2(_value, _dst, &len, &kk); len = Prettify(_dst, len, kk); } return len + sign; } static void reverse(char* _dst, int32_t _len) { for (int32_t ii = 0, jj = _len - 1; ii < jj; ++ii, --jj) { xchg(_dst[ii], _dst[jj]); } } template int32_t toStringSigned(char* _dst, int32_t _max, Ty _value, uint32_t _base) { if (_base == 10 && _value < 0) { if (_max < 1) { return 0; } _max = toString(_dst + 1 , _max - 1 , typename std::make_unsigned::type(-_value) , _base ); if (_max == 0) { return 0; } *_dst = '-'; return int32_t(_max + 1); } return toString(_dst , _max , typename std::make_unsigned::type(_value) , _base ); } int32_t toString(char* _dst, int32_t _max, int32_t _value, uint32_t _base) { return toStringSigned(_dst, _max, _value, _base); } int32_t toString(char* _dst, int32_t _max, int64_t _value, uint32_t _base) { return toStringSigned(_dst, _max, _value, _base); } template int32_t toStringUnsigned(char* _dst, int32_t _max, Ty _value, uint32_t _base) { char data[32]; int32_t len = 0; if (_base > 16 || _base < 2) { return 0; } do { const Ty rem = _value % _base; _value /= _base; if (rem < 10) { data[len++] = char('0' + rem); } else { data[len++] = char('a' + rem - 10); } } while (_value != 0); if (_max < len + 1) { return 0; } reverse(data, len); memCopy(_dst, data, len); _dst[len] = '\0'; return int32_t(len); } int32_t toString(char* _dst, int32_t _max, uint32_t _value, uint32_t _base) { return toStringUnsigned(_dst, _max, _value, _base); } int32_t toString(char* _dst, int32_t _max, uint64_t _value, uint32_t _base) { return toStringUnsigned(_dst, _max, _value, _base); } } // namespace bx