tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
Log | Files | Refs | README | LICENSE

double-conversion-cached-powers.cpp (10413B)


      1 // © 2018 and later: Unicode, Inc. and others.
      2 // License & terms of use: http://www.unicode.org/copyright.html
      3 //
      4 // From the double-conversion library. Original license:
      5 //
      6 // Copyright 2006-2008 the V8 project authors. All rights reserved.
      7 // Redistribution and use in source and binary forms, with or without
      8 // modification, are permitted provided that the following conditions are
      9 // met:
     10 //
     11 //     * Redistributions of source code must retain the above copyright
     12 //       notice, this list of conditions and the following disclaimer.
     13 //     * Redistributions in binary form must reproduce the above
     14 //       copyright notice, this list of conditions and the following
     15 //       disclaimer in the documentation and/or other materials provided
     16 //       with the distribution.
     17 //     * Neither the name of Google Inc. nor the names of its
     18 //       contributors may be used to endorse or promote products derived
     19 //       from this software without specific prior written permission.
     20 //
     21 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     22 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     23 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     24 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     25 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     26 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     27 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     28 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     29 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     30 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     31 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     32 
     33 // ICU PATCH: ifdef around UCONFIG_NO_FORMATTING
     34 #include "unicode/utypes.h"
     35 #if !UCONFIG_NO_FORMATTING
     36 
     37 #include <climits>
     38 #include <cmath>
     39 #include <cstdarg>
     40 
     41 // ICU PATCH: Customize header file paths for ICU.
     42 
     43 #include "double-conversion-utils.h"
     44 
     45 #include "double-conversion-cached-powers.h"
     46 
     47 // ICU PATCH: Wrap in ICU namespace
     48 U_NAMESPACE_BEGIN
     49 
     50 namespace double_conversion::PowersOfTenCache {
     51 
     52 struct CachedPower {
     53  uint64_t significand;
     54  int16_t binary_exponent;
     55  int16_t decimal_exponent;
     56 };
     57 
     58 static const CachedPower kCachedPowers[] = {
     59  {DOUBLE_CONVERSION_UINT64_2PART_C(0xfa8fd5a0, 081c0288), -1220, -348},
     60  {DOUBLE_CONVERSION_UINT64_2PART_C(0xbaaee17f, a23ebf76), -1193, -340},
     61  {DOUBLE_CONVERSION_UINT64_2PART_C(0x8b16fb20, 3055ac76), -1166, -332},
     62  {DOUBLE_CONVERSION_UINT64_2PART_C(0xcf42894a, 5dce35ea), -1140, -324},
     63  {DOUBLE_CONVERSION_UINT64_2PART_C(0x9a6bb0aa, 55653b2d), -1113, -316},
     64  {DOUBLE_CONVERSION_UINT64_2PART_C(0xe61acf03, 3d1a45df), -1087, -308},
     65  {DOUBLE_CONVERSION_UINT64_2PART_C(0xab70fe17, c79ac6ca), -1060, -300},
     66  {DOUBLE_CONVERSION_UINT64_2PART_C(0xff77b1fc, bebcdc4f), -1034, -292},
     67  {DOUBLE_CONVERSION_UINT64_2PART_C(0xbe5691ef, 416bd60c), -1007, -284},
     68  {DOUBLE_CONVERSION_UINT64_2PART_C(0x8dd01fad, 907ffc3c), -980, -276},
     69  {DOUBLE_CONVERSION_UINT64_2PART_C(0xd3515c28, 31559a83), -954, -268},
     70  {DOUBLE_CONVERSION_UINT64_2PART_C(0x9d71ac8f, ada6c9b5), -927, -260},
     71  {DOUBLE_CONVERSION_UINT64_2PART_C(0xea9c2277, 23ee8bcb), -901, -252},
     72  {DOUBLE_CONVERSION_UINT64_2PART_C(0xaecc4991, 4078536d), -874, -244},
     73  {DOUBLE_CONVERSION_UINT64_2PART_C(0x823c1279, 5db6ce57), -847, -236},
     74  {DOUBLE_CONVERSION_UINT64_2PART_C(0xc2109436, 4dfb5637), -821, -228},
     75  {DOUBLE_CONVERSION_UINT64_2PART_C(0x9096ea6f, 3848984f), -794, -220},
     76  {DOUBLE_CONVERSION_UINT64_2PART_C(0xd77485cb, 25823ac7), -768, -212},
     77  {DOUBLE_CONVERSION_UINT64_2PART_C(0xa086cfcd, 97bf97f4), -741, -204},
     78  {DOUBLE_CONVERSION_UINT64_2PART_C(0xef340a98, 172aace5), -715, -196},
     79  {DOUBLE_CONVERSION_UINT64_2PART_C(0xb23867fb, 2a35b28e), -688, -188},
     80  {DOUBLE_CONVERSION_UINT64_2PART_C(0x84c8d4df, d2c63f3b), -661, -180},
     81  {DOUBLE_CONVERSION_UINT64_2PART_C(0xc5dd4427, 1ad3cdba), -635, -172},
     82  {DOUBLE_CONVERSION_UINT64_2PART_C(0x936b9fce, bb25c996), -608, -164},
     83  {DOUBLE_CONVERSION_UINT64_2PART_C(0xdbac6c24, 7d62a584), -582, -156},
     84  {DOUBLE_CONVERSION_UINT64_2PART_C(0xa3ab6658, 0d5fdaf6), -555, -148},
     85  {DOUBLE_CONVERSION_UINT64_2PART_C(0xf3e2f893, dec3f126), -529, -140},
     86  {DOUBLE_CONVERSION_UINT64_2PART_C(0xb5b5ada8, aaff80b8), -502, -132},
     87  {DOUBLE_CONVERSION_UINT64_2PART_C(0x87625f05, 6c7c4a8b), -475, -124},
     88  {DOUBLE_CONVERSION_UINT64_2PART_C(0xc9bcff60, 34c13053), -449, -116},
     89  {DOUBLE_CONVERSION_UINT64_2PART_C(0x964e858c, 91ba2655), -422, -108},
     90  {DOUBLE_CONVERSION_UINT64_2PART_C(0xdff97724, 70297ebd), -396, -100},
     91  {DOUBLE_CONVERSION_UINT64_2PART_C(0xa6dfbd9f, b8e5b88f), -369, -92},
     92  {DOUBLE_CONVERSION_UINT64_2PART_C(0xf8a95fcf, 88747d94), -343, -84},
     93  {DOUBLE_CONVERSION_UINT64_2PART_C(0xb9447093, 8fa89bcf), -316, -76},
     94  {DOUBLE_CONVERSION_UINT64_2PART_C(0x8a08f0f8, bf0f156b), -289, -68},
     95  {DOUBLE_CONVERSION_UINT64_2PART_C(0xcdb02555, 653131b6), -263, -60},
     96  {DOUBLE_CONVERSION_UINT64_2PART_C(0x993fe2c6, d07b7fac), -236, -52},
     97  {DOUBLE_CONVERSION_UINT64_2PART_C(0xe45c10c4, 2a2b3b06), -210, -44},
     98  {DOUBLE_CONVERSION_UINT64_2PART_C(0xaa242499, 697392d3), -183, -36},
     99  {DOUBLE_CONVERSION_UINT64_2PART_C(0xfd87b5f2, 8300ca0e), -157, -28},
    100  {DOUBLE_CONVERSION_UINT64_2PART_C(0xbce50864, 92111aeb), -130, -20},
    101  {DOUBLE_CONVERSION_UINT64_2PART_C(0x8cbccc09, 6f5088cc), -103, -12},
    102  {DOUBLE_CONVERSION_UINT64_2PART_C(0xd1b71758, e219652c), -77, -4},
    103  {DOUBLE_CONVERSION_UINT64_2PART_C(0x9c400000, 00000000), -50, 4},
    104  {DOUBLE_CONVERSION_UINT64_2PART_C(0xe8d4a510, 00000000), -24, 12},
    105  {DOUBLE_CONVERSION_UINT64_2PART_C(0xad78ebc5, ac620000), 3, 20},
    106  {DOUBLE_CONVERSION_UINT64_2PART_C(0x813f3978, f8940984), 30, 28},
    107  {DOUBLE_CONVERSION_UINT64_2PART_C(0xc097ce7b, c90715b3), 56, 36},
    108  {DOUBLE_CONVERSION_UINT64_2PART_C(0x8f7e32ce, 7bea5c70), 83, 44},
    109  {DOUBLE_CONVERSION_UINT64_2PART_C(0xd5d238a4, abe98068), 109, 52},
    110  {DOUBLE_CONVERSION_UINT64_2PART_C(0x9f4f2726, 179a2245), 136, 60},
    111  {DOUBLE_CONVERSION_UINT64_2PART_C(0xed63a231, d4c4fb27), 162, 68},
    112  {DOUBLE_CONVERSION_UINT64_2PART_C(0xb0de6538, 8cc8ada8), 189, 76},
    113  {DOUBLE_CONVERSION_UINT64_2PART_C(0x83c7088e, 1aab65db), 216, 84},
    114  {DOUBLE_CONVERSION_UINT64_2PART_C(0xc45d1df9, 42711d9a), 242, 92},
    115  {DOUBLE_CONVERSION_UINT64_2PART_C(0x924d692c, a61be758), 269, 100},
    116  {DOUBLE_CONVERSION_UINT64_2PART_C(0xda01ee64, 1a708dea), 295, 108},
    117  {DOUBLE_CONVERSION_UINT64_2PART_C(0xa26da399, 9aef774a), 322, 116},
    118  {DOUBLE_CONVERSION_UINT64_2PART_C(0xf209787b, b47d6b85), 348, 124},
    119  {DOUBLE_CONVERSION_UINT64_2PART_C(0xb454e4a1, 79dd1877), 375, 132},
    120  {DOUBLE_CONVERSION_UINT64_2PART_C(0x865b8692, 5b9bc5c2), 402, 140},
    121  {DOUBLE_CONVERSION_UINT64_2PART_C(0xc83553c5, c8965d3d), 428, 148},
    122  {DOUBLE_CONVERSION_UINT64_2PART_C(0x952ab45c, fa97a0b3), 455, 156},
    123  {DOUBLE_CONVERSION_UINT64_2PART_C(0xde469fbd, 99a05fe3), 481, 164},
    124  {DOUBLE_CONVERSION_UINT64_2PART_C(0xa59bc234, db398c25), 508, 172},
    125  {DOUBLE_CONVERSION_UINT64_2PART_C(0xf6c69a72, a3989f5c), 534, 180},
    126  {DOUBLE_CONVERSION_UINT64_2PART_C(0xb7dcbf53, 54e9bece), 561, 188},
    127  {DOUBLE_CONVERSION_UINT64_2PART_C(0x88fcf317, f22241e2), 588, 196},
    128  {DOUBLE_CONVERSION_UINT64_2PART_C(0xcc20ce9b, d35c78a5), 614, 204},
    129  {DOUBLE_CONVERSION_UINT64_2PART_C(0x98165af3, 7b2153df), 641, 212},
    130  {DOUBLE_CONVERSION_UINT64_2PART_C(0xe2a0b5dc, 971f303a), 667, 220},
    131  {DOUBLE_CONVERSION_UINT64_2PART_C(0xa8d9d153, 5ce3b396), 694, 228},
    132  {DOUBLE_CONVERSION_UINT64_2PART_C(0xfb9b7cd9, a4a7443c), 720, 236},
    133  {DOUBLE_CONVERSION_UINT64_2PART_C(0xbb764c4c, a7a44410), 747, 244},
    134  {DOUBLE_CONVERSION_UINT64_2PART_C(0x8bab8eef, b6409c1a), 774, 252},
    135  {DOUBLE_CONVERSION_UINT64_2PART_C(0xd01fef10, a657842c), 800, 260},
    136  {DOUBLE_CONVERSION_UINT64_2PART_C(0x9b10a4e5, e9913129), 827, 268},
    137  {DOUBLE_CONVERSION_UINT64_2PART_C(0xe7109bfb, a19c0c9d), 853, 276},
    138  {DOUBLE_CONVERSION_UINT64_2PART_C(0xac2820d9, 623bf429), 880, 284},
    139  {DOUBLE_CONVERSION_UINT64_2PART_C(0x80444b5e, 7aa7cf85), 907, 292},
    140  {DOUBLE_CONVERSION_UINT64_2PART_C(0xbf21e440, 03acdd2d), 933, 300},
    141  {DOUBLE_CONVERSION_UINT64_2PART_C(0x8e679c2f, 5e44ff8f), 960, 308},
    142  {DOUBLE_CONVERSION_UINT64_2PART_C(0xd433179d, 9c8cb841), 986, 316},
    143  {DOUBLE_CONVERSION_UINT64_2PART_C(0x9e19db92, b4e31ba9), 1013, 324},
    144  {DOUBLE_CONVERSION_UINT64_2PART_C(0xeb96bf6e, badf77d9), 1039, 332},
    145  {DOUBLE_CONVERSION_UINT64_2PART_C(0xaf87023b, 9bf0ee6b), 1066, 340},
    146 };
    147 
    148 static const int kCachedPowersOffset = 348;  // -1 * the first decimal_exponent.
    149 static const double kD_1_LOG2_10 = 0.30102999566398114;  //  1 / lg(10)
    150 
    151 void GetCachedPowerForBinaryExponentRange(
    152    int min_exponent,
    153    int max_exponent,
    154    DiyFp* power,
    155    int* decimal_exponent) {
    156  int kQ = DiyFp::kSignificandSize;
    157  double k = ceil((min_exponent + kQ - 1) * kD_1_LOG2_10);
    158  int foo = kCachedPowersOffset;
    159  int index =
    160      (foo + static_cast<int>(k) - 1) / kDecimalExponentDistance + 1;
    161  DOUBLE_CONVERSION_ASSERT(0 <= index && index < static_cast<int>(DOUBLE_CONVERSION_ARRAY_SIZE(kCachedPowers)));
    162  CachedPower cached_power = kCachedPowers[index];
    163  DOUBLE_CONVERSION_ASSERT(min_exponent <= cached_power.binary_exponent);
    164  (void) max_exponent;  // Mark variable as used.
    165  DOUBLE_CONVERSION_ASSERT(cached_power.binary_exponent <= max_exponent);
    166  *decimal_exponent = cached_power.decimal_exponent;
    167  *power = DiyFp(cached_power.significand, cached_power.binary_exponent);
    168 }
    169 
    170 
    171 void GetCachedPowerForDecimalExponent(int requested_exponent,
    172                                      DiyFp* power,
    173                                      int* found_exponent) {
    174  DOUBLE_CONVERSION_ASSERT(kMinDecimalExponent <= requested_exponent);
    175  DOUBLE_CONVERSION_ASSERT(requested_exponent < kMaxDecimalExponent + kDecimalExponentDistance);
    176  int index =
    177      (requested_exponent + kCachedPowersOffset) / kDecimalExponentDistance;
    178  CachedPower cached_power = kCachedPowers[index];
    179  *power = DiyFp(cached_power.significand, cached_power.binary_exponent);
    180  *found_exponent = cached_power.decimal_exponent;
    181  DOUBLE_CONVERSION_ASSERT(*found_exponent <= requested_exponent);
    182  DOUBLE_CONVERSION_ASSERT(requested_exponent < *found_exponent + kDecimalExponentDistance);
    183 }
    184 
    185 } // namespace double_conversion::PowersOfTenCache
    186 
    187 // ICU PATCH: Close ICU namespace
    188 U_NAMESPACE_END
    189 #endif // ICU PATCH: close #if !UCONFIG_NO_FORMATTING