summaryrefslogtreecommitdiffstats
path: root/src/3rdparty/angle/src/common/bitset_utils.h
diff options
context:
space:
mode:
Diffstat (limited to 'src/3rdparty/angle/src/common/bitset_utils.h')
-rw-r--r--src/3rdparty/angle/src/common/bitset_utils.h498
1 files changed, 498 insertions, 0 deletions
diff --git a/src/3rdparty/angle/src/common/bitset_utils.h b/src/3rdparty/angle/src/common/bitset_utils.h
new file mode 100644
index 0000000000..4166a562a7
--- /dev/null
+++ b/src/3rdparty/angle/src/common/bitset_utils.h
@@ -0,0 +1,498 @@
+//
+// Copyright 2015 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// bitset_utils:
+// Bitset-related helper classes, such as a fast iterator to scan for set bits.
+//
+
+#ifndef COMMON_BITSETITERATOR_H_
+#define COMMON_BITSETITERATOR_H_
+
+#include <stdint.h>
+
+#include <bitset>
+
+#include "common/angleutils.h"
+#include "common/debug.h"
+#include "common/mathutil.h"
+#include "common/platform.h"
+
+namespace angle
+{
+
+template <size_t N, typename BitsT>
+class BitSetT final
+{
+ public:
+ class Reference final
+ {
+ public:
+ ~Reference() {}
+ Reference &operator=(bool x)
+ {
+ mParent->set(mBit, x);
+ return *this;
+ }
+ explicit operator bool() const { return mParent->test(mBit); }
+
+ private:
+ friend class BitSetT;
+
+ Reference(BitSetT *parent, std::size_t bit) : mParent(parent), mBit(bit) {}
+
+ BitSetT *mParent;
+ std::size_t mBit;
+ };
+
+ class Iterator final
+ {
+ public:
+ Iterator(const BitSetT &bits);
+ Iterator &operator++();
+
+ bool operator==(const Iterator &other) const;
+ bool operator!=(const Iterator &other) const;
+ std::size_t operator*() const;
+
+ private:
+ std::size_t getNextBit();
+
+ BitSetT mBitsCopy;
+ std::size_t mCurrentBit;
+ };
+
+ BitSetT();
+ BitSetT(BitsT value);
+ ~BitSetT();
+
+ BitSetT(const BitSetT &other);
+ BitSetT &operator=(const BitSetT &other);
+
+ bool operator==(const BitSetT &other) const;
+ bool operator!=(const BitSetT &other) const;
+
+ constexpr bool operator[](std::size_t pos) const;
+ Reference operator[](std::size_t pos) { return Reference(this, pos); }
+
+ bool test(std::size_t pos) const;
+
+ bool all() const;
+ bool any() const;
+ bool none() const;
+ std::size_t count() const;
+
+ constexpr std::size_t size() const { return N; }
+
+ BitSetT &operator&=(const BitSetT &other);
+ BitSetT &operator|=(const BitSetT &other);
+ BitSetT &operator^=(const BitSetT &other);
+ BitSetT operator~() const;
+
+ BitSetT operator<<(std::size_t pos) const;
+ BitSetT &operator<<=(std::size_t pos);
+ BitSetT operator>>(std::size_t pos) const;
+ BitSetT &operator>>=(std::size_t pos);
+
+ BitSetT &set();
+ BitSetT &set(std::size_t pos, bool value = true);
+
+ BitSetT &reset();
+ BitSetT &reset(std::size_t pos);
+
+ BitSetT &flip();
+ BitSetT &flip(std::size_t pos);
+
+ unsigned long to_ulong() const { return static_cast<unsigned long>(mBits); }
+ BitsT bits() const { return mBits; }
+
+ Iterator begin() const { return Iterator(*this); }
+ Iterator end() const { return Iterator(BitSetT()); }
+
+ private:
+ constexpr static BitsT Bit(std::size_t x) { return (static_cast<BitsT>(1) << x); }
+ constexpr static BitsT Mask(std::size_t x) { return ((Bit(x - 1) - 1) << 1) + 1; }
+
+ BitsT mBits;
+};
+
+template <size_t N>
+class IterableBitSet : public std::bitset<N>
+{
+ public:
+ IterableBitSet() {}
+ IterableBitSet(const std::bitset<N> &implicitBitSet) : std::bitset<N>(implicitBitSet) {}
+
+ class Iterator final
+ {
+ public:
+ Iterator(const std::bitset<N> &bits);
+ Iterator &operator++();
+
+ bool operator==(const Iterator &other) const;
+ bool operator!=(const Iterator &other) const;
+ unsigned long operator*() const { return mCurrentBit; }
+
+ private:
+ unsigned long getNextBit();
+
+ static constexpr size_t BitsPerWord = sizeof(uint32_t) * 8;
+ std::bitset<N> mBits;
+ unsigned long mCurrentBit;
+ unsigned long mOffset;
+ };
+
+ Iterator begin() const { return Iterator(*this); }
+ Iterator end() const { return Iterator(std::bitset<N>(0)); }
+};
+
+template <size_t N>
+IterableBitSet<N>::Iterator::Iterator(const std::bitset<N> &bitset)
+ : mBits(bitset), mCurrentBit(0), mOffset(0)
+{
+ if (mBits.any())
+ {
+ mCurrentBit = getNextBit();
+ }
+ else
+ {
+ mOffset = static_cast<unsigned long>(rx::roundUp(N, BitsPerWord));
+ }
+}
+
+template <size_t N>
+typename IterableBitSet<N>::Iterator &IterableBitSet<N>::Iterator::operator++()
+{
+ ASSERT(mBits.any());
+ mBits.set(mCurrentBit - mOffset, 0);
+ mCurrentBit = getNextBit();
+ return *this;
+}
+
+template <size_t N>
+bool IterableBitSet<N>::Iterator::operator==(const Iterator &other) const
+{
+ return mOffset == other.mOffset && mBits == other.mBits;
+}
+
+template <size_t N>
+bool IterableBitSet<N>::Iterator::operator!=(const Iterator &other) const
+{
+ return !(*this == other);
+}
+
+template <size_t N>
+unsigned long IterableBitSet<N>::Iterator::getNextBit()
+{
+ // TODO(jmadill): Use 64-bit scan when possible.
+ static constexpr std::bitset<N> wordMask(std::numeric_limits<uint32_t>::max());
+
+ while (mOffset < N)
+ {
+ uint32_t wordBits = static_cast<uint32_t>((mBits & wordMask).to_ulong());
+ if (wordBits != 0)
+ {
+ return gl::ScanForward(wordBits) + mOffset;
+ }
+
+ mBits >>= BitsPerWord;
+ mOffset += BitsPerWord;
+ }
+ return 0;
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT>::BitSetT() : mBits(0)
+{
+ static_assert(N > 0, "Bitset type cannot support zero bits.");
+ static_assert(N <= sizeof(BitsT) * 8, "Bitset type cannot support a size this large.");
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT>::BitSetT(BitsT value) : mBits(value & Mask(N))
+{
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT>::~BitSetT()
+{
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT>::BitSetT(const BitSetT &other) : mBits(other.mBits)
+{
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> &BitSetT<N, BitsT>::operator=(const BitSetT &other)
+{
+ mBits = other.mBits;
+ return *this;
+}
+
+template <size_t N, typename BitsT>
+bool BitSetT<N, BitsT>::operator==(const BitSetT &other) const
+{
+ return mBits == other.mBits;
+}
+
+template <size_t N, typename BitsT>
+bool BitSetT<N, BitsT>::operator!=(const BitSetT &other) const
+{
+ return mBits != other.mBits;
+}
+
+template <size_t N, typename BitsT>
+constexpr bool BitSetT<N, BitsT>::operator[](std::size_t pos) const
+{
+ return test(pos);
+}
+
+template <size_t N, typename BitsT>
+bool BitSetT<N, BitsT>::test(std::size_t pos) const
+{
+ return (mBits & Bit(pos)) != 0;
+}
+
+template <size_t N, typename BitsT>
+bool BitSetT<N, BitsT>::all() const
+{
+ ASSERT(mBits == (mBits & Mask(N)));
+ return mBits == Mask(N);
+}
+
+template <size_t N, typename BitsT>
+bool BitSetT<N, BitsT>::any() const
+{
+ ASSERT(mBits == (mBits & Mask(N)));
+ return (mBits != 0);
+}
+
+template <size_t N, typename BitsT>
+bool BitSetT<N, BitsT>::none() const
+{
+ ASSERT(mBits == (mBits & Mask(N)));
+ return (mBits == 0);
+}
+
+template <size_t N, typename BitsT>
+std::size_t BitSetT<N, BitsT>::count() const
+{
+ return gl::BitCount(mBits);
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> &BitSetT<N, BitsT>::operator&=(const BitSetT &other)
+{
+ mBits &= other.mBits;
+ return *this;
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> &BitSetT<N, BitsT>::operator|=(const BitSetT &other)
+{
+ mBits |= other.mBits;
+ return *this;
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> &BitSetT<N, BitsT>::operator^=(const BitSetT &other)
+{
+ mBits = (mBits ^ other.mBits) & Mask(N);
+ return *this;
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> BitSetT<N, BitsT>::operator~() const
+{
+ return BitSetT<N, BitsT>(~mBits & Mask(N));
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> BitSetT<N, BitsT>::operator<<(std::size_t pos) const
+{
+ return BitSetT<N, BitsT>((mBits << pos) & Mask(N));
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> &BitSetT<N, BitsT>::operator<<=(std::size_t pos)
+{
+ mBits = (mBits << pos & Mask(N));
+ return *this;
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> BitSetT<N, BitsT>::operator>>(std::size_t pos) const
+{
+ return BitSetT<N, BitsT>(mBits >> pos);
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> &BitSetT<N, BitsT>::operator>>=(std::size_t pos)
+{
+ mBits = ((mBits >> pos) & Mask(N));
+ return *this;
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> &BitSetT<N, BitsT>::set()
+{
+ mBits = Mask(N);
+ return *this;
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> &BitSetT<N, BitsT>::set(std::size_t pos, bool value)
+{
+ if (value)
+ {
+ mBits |= Bit(pos);
+ }
+ else
+ {
+ reset(pos);
+ }
+ return *this;
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> &BitSetT<N, BitsT>::reset()
+{
+ mBits = 0;
+ return *this;
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> &BitSetT<N, BitsT>::reset(std::size_t pos)
+{
+ mBits &= ~Bit(pos);
+ return *this;
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> &BitSetT<N, BitsT>::flip()
+{
+ mBits ^= Mask(N);
+ return *this;
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT> &BitSetT<N, BitsT>::flip(std::size_t pos)
+{
+ mBits ^= Bit(pos);
+ return *this;
+}
+
+template <size_t N, typename BitsT>
+BitSetT<N, BitsT>::Iterator::Iterator(const BitSetT &bits) : mBitsCopy(bits), mCurrentBit(0)
+{
+ if (bits.any())
+ {
+ mCurrentBit = getNextBit();
+ }
+}
+
+template <size_t N, typename BitsT>
+typename BitSetT<N, BitsT>::Iterator &BitSetT<N, BitsT>::Iterator::operator++()
+{
+ ASSERT(mBitsCopy.any());
+ mBitsCopy.reset(mCurrentBit);
+ mCurrentBit = getNextBit();
+ return *this;
+}
+
+template <size_t N, typename BitsT>
+bool BitSetT<N, BitsT>::Iterator::operator==(const Iterator &other) const
+{
+ return mBitsCopy == other.mBitsCopy;
+}
+
+template <size_t N, typename BitsT>
+bool BitSetT<N, BitsT>::Iterator::operator!=(const Iterator &other) const
+{
+ return !(*this == other);
+}
+
+template <size_t N, typename BitsT>
+std::size_t BitSetT<N, BitsT>::Iterator::operator*() const
+{
+ return mCurrentBit;
+}
+
+template <size_t N, typename BitsT>
+std::size_t BitSetT<N, BitsT>::Iterator::getNextBit()
+{
+ if (mBitsCopy.none())
+ {
+ return 0;
+ }
+
+ return gl::ScanForward(mBitsCopy.mBits);
+}
+
+template <size_t N>
+using BitSet32 = BitSetT<N, uint32_t>;
+
+// ScanForward for 64-bits requires a 64-bit implementation.
+#if defined(ANGLE_IS_64_BIT_CPU)
+template <size_t N>
+using BitSet64 = BitSetT<N, uint64_t>;
+#endif // defined(ANGLE_IS_64_BIT_CPU)
+
+namespace priv
+{
+
+template <size_t N, typename T>
+using EnableIfBitsFit = typename std::enable_if<N <= sizeof(T) * 8>::type;
+
+template <size_t N, typename Enable = void>
+struct GetBitSet
+{
+ using Type = IterableBitSet<N>;
+};
+
+// Prefer 64-bit bitsets on 64-bit CPUs. They seem faster than 32-bit.
+#if defined(ANGLE_IS_64_BIT_CPU)
+template <size_t N>
+struct GetBitSet<N, EnableIfBitsFit<N, uint64_t>>
+{
+ using Type = BitSet64<N>;
+};
+#else
+template <size_t N>
+struct GetBitSet<N, EnableIfBitsFit<N, uint32_t>>
+{
+ using Type = BitSet32<N>;
+};
+#endif // defined(ANGLE_IS_64_BIT_CPU)
+
+} // namespace priv
+
+template <size_t N>
+using BitSet = typename priv::GetBitSet<N>::Type;
+
+} // angle
+
+template <size_t N, typename BitsT>
+inline angle::BitSetT<N, BitsT> operator&(const angle::BitSetT<N, BitsT> &lhs,
+ const angle::BitSetT<N, BitsT> &rhs)
+{
+ return angle::BitSetT<N, BitsT>(lhs.bits() & rhs.bits());
+}
+
+template <size_t N, typename BitsT>
+inline angle::BitSetT<N, BitsT> operator|(const angle::BitSetT<N, BitsT> &lhs,
+ const angle::BitSetT<N, BitsT> &rhs)
+{
+ return angle::BitSetT<N, BitsT>(lhs.bits() | rhs.bits());
+}
+
+template <size_t N, typename BitsT>
+inline angle::BitSetT<N, BitsT> operator^(const angle::BitSetT<N, BitsT> &lhs,
+ const angle::BitSetT<N, BitsT> &rhs)
+{
+ return angle::BitSetT<N, BitsT>(lhs.bits() ^ rhs.bits());
+}
+
+#endif // COMMON_BITSETITERATOR_H_