81 lines
1.5 KiB
C++
81 lines
1.5 KiB
C++
// Copyright 2018 yuzu emulator team
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// Licensed under GPLv2 or any later version
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// Refer to the license.txt file included.
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#pragma once
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#include <climits>
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#include <cstddef>
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#ifdef _MSC_VER
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#include <intrin.h>
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#endif
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#include "common/common_types.h"
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namespace Common {
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/// Gets the size of a specified type T in bits.
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template <typename T>
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constexpr std::size_t BitSize() {
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return sizeof(T) * CHAR_BIT;
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}
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#ifdef _MSC_VER
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inline u32 CountLeadingZeroes32(u32 value) {
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unsigned long leading_zero = 0;
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if (_BitScanReverse(&leading_zero, value) != 0) {
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return 31 - leading_zero;
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}
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return 32;
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}
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inline u64 CountLeadingZeroes64(u64 value) {
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unsigned long leading_zero = 0;
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if (_BitScanReverse64(&leading_zero, value) != 0) {
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return 63 - leading_zero;
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}
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return 64;
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}
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#else
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inline u32 CountLeadingZeroes32(u32 value) {
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if (value == 0) {
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return 32;
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}
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return __builtin_clz(value);
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}
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inline u64 CountLeadingZeroes64(u64 value) {
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if (value == 0) {
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return 64;
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}
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return __builtin_clzll(value);
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}
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#endif
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inline u32 CountTrailingZeroes32(u32 value) {
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u32 count = 0;
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while (((value >> count) & 0xf) == 0 && count < 32)
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count += 4;
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while (((value >> count) & 1) == 0 && count < 32)
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count++;
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return count;
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}
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inline u64 CountTrailingZeroes64(u64 value) {
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u64 count = 0;
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while (((value >> count) & 0xf) == 0 && count < 64)
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count += 4;
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while (((value >> count) & 1) == 0 && count < 64)
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count++;
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return count;
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}
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} // namespace Common
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