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authorLioncash <mathew1800@gmail.com>2018-11-22 03:29:39 +0100
committerLioncash <mathew1800@gmail.com>2018-11-22 03:30:10 +0100
commit8b27e73bd7f5fe8671606867614b51dacfbf3d1b (patch)
treebc1ebdf97a445518658ecc2a429e6cb0ca0b809b /src/common/bit_set.h
parentMerge pull request #1753 from FernandoS27/ufbtype (diff)
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Diffstat (limited to '')
-rw-r--r--src/common/bit_set.h244
1 files changed, 0 insertions, 244 deletions
diff --git a/src/common/bit_set.h b/src/common/bit_set.h
deleted file mode 100644
index 5cd1352b2..000000000
--- a/src/common/bit_set.h
+++ /dev/null
@@ -1,244 +0,0 @@
-// This file is under the public domain.
-
-#pragma once
-
-#include <cstddef>
-#ifdef _WIN32
-#include <intrin.h>
-#endif
-#include <initializer_list>
-#include <new>
-#include <type_traits>
-#include "common/common_types.h"
-
-// namespace avoids conflict with OS X Carbon; don't use BitSet<T> directly
-namespace Common {
-
-// Helper functions:
-
-#ifdef _MSC_VER
-template <typename T>
-static inline int CountSetBits(T v) {
- // from https://graphics.stanford.edu/~seander/bithacks.html
- // GCC has this built in, but MSVC's intrinsic will only emit the actual
- // POPCNT instruction, which we're not depending on
- v = v - ((v >> 1) & (T) ~(T)0 / 3);
- v = (v & (T) ~(T)0 / 15 * 3) + ((v >> 2) & (T) ~(T)0 / 15 * 3);
- v = (v + (v >> 4)) & (T) ~(T)0 / 255 * 15;
- return (T)(v * ((T) ~(T)0 / 255)) >> (sizeof(T) - 1) * 8;
-}
-static inline int LeastSignificantSetBit(u8 val) {
- unsigned long index;
- _BitScanForward(&index, val);
- return (int)index;
-}
-static inline int LeastSignificantSetBit(u16 val) {
- unsigned long index;
- _BitScanForward(&index, val);
- return (int)index;
-}
-static inline int LeastSignificantSetBit(u32 val) {
- unsigned long index;
- _BitScanForward(&index, val);
- return (int)index;
-}
-static inline int LeastSignificantSetBit(u64 val) {
- unsigned long index;
- _BitScanForward64(&index, val);
- return (int)index;
-}
-#else
-static inline int CountSetBits(u8 val) {
- return __builtin_popcount(val);
-}
-static inline int CountSetBits(u16 val) {
- return __builtin_popcount(val);
-}
-static inline int CountSetBits(u32 val) {
- return __builtin_popcount(val);
-}
-static inline int CountSetBits(u64 val) {
- return __builtin_popcountll(val);
-}
-static inline int LeastSignificantSetBit(u8 val) {
- return __builtin_ctz(val);
-}
-static inline int LeastSignificantSetBit(u16 val) {
- return __builtin_ctz(val);
-}
-static inline int LeastSignificantSetBit(u32 val) {
- return __builtin_ctz(val);
-}
-static inline int LeastSignificantSetBit(u64 val) {
- return __builtin_ctzll(val);
-}
-#endif
-
-// Similar to std::bitset, this is a class which encapsulates a bitset, i.e.
-// using the set bits of an integer to represent a set of integers. Like that
-// class, it acts like an array of bools:
-// BitSet32 bs;
-// bs[1] = true;
-// but also like the underlying integer ([0] = least significant bit):
-// BitSet32 bs2 = ...;
-// bs = (bs ^ bs2) & BitSet32(0xffff);
-// The following additional functionality is provided:
-// - Construction using an initializer list.
-// BitSet bs { 1, 2, 4, 8 };
-// - Efficiently iterating through the set bits:
-// for (int i : bs)
-// [i is the *index* of a set bit]
-// (This uses the appropriate CPU instruction to find the next set bit in one
-// operation.)
-// - Counting set bits using .Count() - see comment on that method.
-
-// TODO: use constexpr when MSVC gets out of the Dark Ages
-
-template <typename IntTy>
-class BitSet {
- static_assert(!std::is_signed_v<IntTy>, "BitSet should not be used with signed types");
-
-public:
- // A reference to a particular bit, returned from operator[].
- class Ref {
- public:
- Ref(Ref&& other) : m_bs(other.m_bs), m_mask(other.m_mask) {}
- Ref(BitSet* bs, IntTy mask) : m_bs(bs), m_mask(mask) {}
- operator bool() const {
- return (m_bs->m_val & m_mask) != 0;
- }
- bool operator=(bool set) {
- m_bs->m_val = (m_bs->m_val & ~m_mask) | (set ? m_mask : 0);
- return set;
- }
-
- private:
- BitSet* m_bs;
- IntTy m_mask;
- };
-
- // A STL-like iterator is required to be able to use range-based for loops.
- class Iterator {
- public:
- Iterator(const Iterator& other) : m_val(other.m_val), m_bit(other.m_bit) {}
- Iterator(IntTy val) : m_val(val), m_bit(0) {}
- Iterator& operator=(Iterator other) {
- new (this) Iterator(other);
- return *this;
- }
- int operator*() {
- return m_bit + ComputeLsb();
- }
- Iterator& operator++() {
- int lsb = ComputeLsb();
- m_val >>= lsb + 1;
- m_bit += lsb + 1;
- m_has_lsb = false;
- return *this;
- }
- Iterator operator++(int _) {
- Iterator other(*this);
- ++*this;
- return other;
- }
- bool operator==(Iterator other) const {
- return m_val == other.m_val;
- }
- bool operator!=(Iterator other) const {
- return m_val != other.m_val;
- }
-
- private:
- int ComputeLsb() {
- if (!m_has_lsb) {
- m_lsb = LeastSignificantSetBit(m_val);
- m_has_lsb = true;
- }
- return m_lsb;
- }
- IntTy m_val;
- int m_bit;
- int m_lsb = -1;
- bool m_has_lsb = false;
- };
-
- BitSet() : m_val(0) {}
- explicit BitSet(IntTy val) : m_val(val) {}
- BitSet(std::initializer_list<int> init) {
- m_val = 0;
- for (int bit : init)
- m_val |= (IntTy)1 << bit;
- }
-
- static BitSet AllTrue(std::size_t count) {
- return BitSet(count == sizeof(IntTy) * 8 ? ~(IntTy)0 : (((IntTy)1 << count) - 1));
- }
-
- Ref operator[](std::size_t bit) {
- return Ref(this, (IntTy)1 << bit);
- }
- const Ref operator[](std::size_t bit) const {
- return (*const_cast<BitSet*>(this))[bit];
- }
- bool operator==(BitSet other) const {
- return m_val == other.m_val;
- }
- bool operator!=(BitSet other) const {
- return m_val != other.m_val;
- }
- bool operator<(BitSet other) const {
- return m_val < other.m_val;
- }
- bool operator>(BitSet other) const {
- return m_val > other.m_val;
- }
- BitSet operator|(BitSet other) const {
- return BitSet(m_val | other.m_val);
- }
- BitSet operator&(BitSet other) const {
- return BitSet(m_val & other.m_val);
- }
- BitSet operator^(BitSet other) const {
- return BitSet(m_val ^ other.m_val);
- }
- BitSet operator~() const {
- return BitSet(~m_val);
- }
- BitSet& operator|=(BitSet other) {
- return *this = *this | other;
- }
- BitSet& operator&=(BitSet other) {
- return *this = *this & other;
- }
- BitSet& operator^=(BitSet other) {
- return *this = *this ^ other;
- }
- operator u32() = delete;
- operator bool() {
- return m_val != 0;
- }
-
- // Warning: Even though on modern CPUs this is a single fast instruction,
- // Dolphin's official builds do not currently assume POPCNT support on x86,
- // so slower explicit bit twiddling is generated. Still should generally
- // be faster than a loop.
- unsigned int Count() const {
- return CountSetBits(m_val);
- }
-
- Iterator begin() const {
- return Iterator(m_val);
- }
- Iterator end() const {
- return Iterator(0);
- }
-
- IntTy m_val;
-};
-
-} // namespace Common
-
-typedef Common::BitSet<u8> BitSet8;
-typedef Common::BitSet<u16> BitSet16;
-typedef Common::BitSet<u32> BitSet32;
-typedef Common::BitSet<u64> BitSet64;