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32 lines
773 B
C++
32 lines
773 B
C++
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/* This file is part of the dynarmic project.
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* Copyright (c) 2018 MerryMage
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* This software may be used and distributed according to the terms of the GNU
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* General Public License version 2 or any later version.
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*/
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#include <array>
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#include "common/math_util.h"
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namespace Dynarmic::Common {
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u8 RecipEstimate(u64 a) {
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using LUT = std::array<u8, 256>;
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static constexpr u64 lut_offset = 256;
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static const LUT lut = [] {
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LUT result{};
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for (u64 i = 0; i < result.size(); i++) {
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u64 a = i + lut_offset;
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a = a * 2 + 1;
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u64 b = (1u << 19) / a;
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result[i] = static_cast<u8>((b + 1) / 2);
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}
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return result;
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}();
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return lut[a - lut_offset];
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}
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} // namespace Dynarmic::Common
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