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Diffstat (limited to 'Build/source/libs/icu/icu-src/source/i18n/double-conversion-diy-fp.h')
-rw-r--r-- | Build/source/libs/icu/icu-src/source/i18n/double-conversion-diy-fp.h | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/Build/source/libs/icu/icu-src/source/i18n/double-conversion-diy-fp.h b/Build/source/libs/icu/icu-src/source/i18n/double-conversion-diy-fp.h new file mode 100644 index 00000000000..21896851d22 --- /dev/null +++ b/Build/source/libs/icu/icu-src/source/i18n/double-conversion-diy-fp.h @@ -0,0 +1,136 @@ +// © 2018 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +// +// From the double-conversion library. Original license: +// +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +// ICU PATCH: ifdef around UCONFIG_NO_FORMATTING +#include "unicode/utypes.h" +#if !UCONFIG_NO_FORMATTING + +#ifndef DOUBLE_CONVERSION_DIY_FP_H_ +#define DOUBLE_CONVERSION_DIY_FP_H_ + +// ICU PATCH: Customize header file paths for ICU. + +#include "double-conversion-utils.h" + +// ICU PATCH: Wrap in ICU namespace +U_NAMESPACE_BEGIN + +namespace double_conversion { + +// This "Do It Yourself Floating Point" class implements a floating-point number +// with a uint64 significand and an int exponent. Normalized DiyFp numbers will +// have the most significant bit of the significand set. +// Multiplication and Subtraction do not normalize their results. +// DiyFp are not designed to contain special doubles (NaN and Infinity). +class DiyFp { + public: + static const int kSignificandSize = 64; + + DiyFp() : f_(0), e_(0) {} + DiyFp(uint64_t significand, int exponent) : f_(significand), e_(exponent) {} + + // this = this - other. + // The exponents of both numbers must be the same and the significand of this + // must be bigger than the significand of other. + // The result will not be normalized. + void Subtract(const DiyFp& other) { + ASSERT(e_ == other.e_); + ASSERT(f_ >= other.f_); + f_ -= other.f_; + } + + // Returns a - b. + // The exponents of both numbers must be the same and this must be bigger + // than other. The result will not be normalized. + static DiyFp Minus(const DiyFp& a, const DiyFp& b) { + DiyFp result = a; + result.Subtract(b); + return result; + } + + + // this = this * other. + void Multiply(const DiyFp& other); + + // returns a * b; + static DiyFp Times(const DiyFp& a, const DiyFp& b) { + DiyFp result = a; + result.Multiply(b); + return result; + } + + void Normalize() { + ASSERT(f_ != 0); + uint64_t significand = f_; + int exponent = e_; + + // This method is mainly called for normalizing boundaries. In general + // boundaries need to be shifted by 10 bits. We thus optimize for this case. + const uint64_t k10MSBits = UINT64_2PART_C(0xFFC00000, 00000000); + while ((significand & k10MSBits) == 0) { + significand <<= 10; + exponent -= 10; + } + while ((significand & kUint64MSB) == 0) { + significand <<= 1; + exponent--; + } + f_ = significand; + e_ = exponent; + } + + static DiyFp Normalize(const DiyFp& a) { + DiyFp result = a; + result.Normalize(); + return result; + } + + uint64_t f() const { return f_; } + int e() const { return e_; } + + void set_f(uint64_t new_value) { f_ = new_value; } + void set_e(int new_value) { e_ = new_value; } + + private: + static const uint64_t kUint64MSB = UINT64_2PART_C(0x80000000, 00000000); + + uint64_t f_; + int e_; +}; + +} // namespace double_conversion + +// ICU PATCH: Close ICU namespace +U_NAMESPACE_END + +#endif // DOUBLE_CONVERSION_DIY_FP_H_ +#endif // ICU PATCH: close #if !UCONFIG_NO_FORMATTING |