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 2010 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 // ICU PATCH: Customize header file paths for ICU. 38 39 #include "double-conversion-diy-fp.h" 40 #include "double-conversion-utils.h" 41 42 // ICU PATCH: Wrap in ICU namespace 43 U_NAMESPACE_BEGIN 44 45 namespace double_conversion { 46 47 void DiyFp::Multiply(const DiyFp& other) { 48 // Simply "emulates" a 128 bit multiplication. 49 // However: the resulting number only contains 64 bits. The least 50 // significant 64 bits are only used for rounding the most significant 64 51 // bits. 52 const uint64_t kM32 = 0xFFFFFFFFU; 53 uint64_t a = f_ >> 32; 54 uint64_t b = f_ & kM32; 55 uint64_t c = other.f_ >> 32; 56 uint64_t d = other.f_ & kM32; 57 uint64_t ac = a * c; 58 uint64_t bc = b * c; 59 uint64_t ad = a * d; 60 uint64_t bd = b * d; 61 uint64_t tmp = (bd >> 32) + (ad & kM32) + (bc & kM32); 62 // By adding 1U << 31 to tmp we round the final result. 63 // Halfway cases will be round up. 64 tmp += 1U << 31; 65 uint64_t result_f = ac + (ad >> 32) + (bc >> 32) + (tmp >> 32); 66 e_ += other.e_ + 64; 67 f_ = result_f; 68 } 69 70 } // namespace double_conversion 71 72 // ICU PATCH: Close ICU namespace 73 U_NAMESPACE_END 74 #endif // ICU PATCH: close #if !UCONFIG_NO_FORMATTING 75
