projects / apple / icu.git / blame
| Commit | Line | Data |
|---|---|---|
| 0f5d89e8 A |
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 |