X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FADT%2FBitVector.h;h=ad00d51f99e9f472c20f5027d63140a9b5267b71;hb=2b762697564ca1e12e0e974e93ceeb4c3420505c;hp=937296b487a6b6a9e8ce50fcaba697818e20f7dd;hpb=e01ad2d129640a404844b3e55c7be4405ac21a24;p=oota-llvm.git diff --git a/include/llvm/ADT/BitVector.h b/include/llvm/ADT/BitVector.h index 937296b487a..ad00d51f99e 100644 --- a/include/llvm/ADT/BitVector.h +++ b/include/llvm/ADT/BitVector.h @@ -2,8 +2,8 @@ // // The LLVM Compiler Infrastructure // -// This file was developed by Evan Cheng and is distributed under -// the University of Illinois Open Source License. See LICENSE.TXT for details. +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // @@ -14,20 +14,30 @@ #ifndef LLVM_ADT_BITVECTOR_H #define LLVM_ADT_BITVECTOR_H +#include "llvm/Support/Compiler.h" +#include "llvm/Support/ErrorHandling.h" #include "llvm/Support/MathExtras.h" +#include +#include +#include +#include namespace llvm { class BitVector { typedef unsigned long BitWord; - enum { BITS_PER_WORD = sizeof(BitWord) * 8 }; + enum { BITWORD_SIZE = (unsigned)sizeof(BitWord) * CHAR_BIT }; - BitWord *Bits; // Actual bits. + static_assert(BITWORD_SIZE == 64 || BITWORD_SIZE == 32, + "Unsupported word size"); + + BitWord *Bits; // Actual bits. unsigned Size; // Size of bitvector in bits. - unsigned Capacity; // Size of allocated memory in BitWord. + unsigned Capacity; // Number of BitWords allocated in the Bits array. public: + typedef unsigned size_type; // Encapsulation of a single bit. class reference { friend class BitVector; @@ -39,36 +49,41 @@ public: public: reference(BitVector &b, unsigned Idx) { - WordRef = &b.Bits[Idx / BITS_PER_WORD]; - BitPos = Idx % BITS_PER_WORD; + WordRef = &b.Bits[Idx / BITWORD_SIZE]; + BitPos = Idx % BITWORD_SIZE; } - ~reference() {} + reference(const reference&) = default; + + reference &operator=(reference t) { + *this = bool(t); + return *this; + } reference& operator=(bool t) { if (t) - *WordRef |= 1L << BitPos; + *WordRef |= BitWord(1) << BitPos; else - *WordRef &= ~(1L << BitPos); + *WordRef &= ~(BitWord(1) << BitPos); return *this; } operator bool() const { - return (*WordRef) & (1L << BitPos); + return ((*WordRef) & (BitWord(1) << BitPos)) ? true : false; } }; /// BitVector default ctor - Creates an empty bitvector. BitVector() : Size(0), Capacity(0) { - Bits = NULL; + Bits = nullptr; } /// BitVector ctor - Creates a bitvector of specified number of bits. All /// bits are initialized to the specified value. explicit BitVector(unsigned s, bool t = false) : Size(s) { Capacity = NumBitWords(s); - Bits = new BitWord[Capacity]; + Bits = (BitWord *)std::malloc(Capacity * sizeof(BitWord)); init_words(Bits, Capacity, t); if (t) clear_unused_bits(); @@ -77,28 +92,36 @@ public: /// BitVector copy ctor. BitVector(const BitVector &RHS) : Size(RHS.size()) { if (Size == 0) { - Bits = NULL; + Bits = nullptr; + Capacity = 0; return; } Capacity = NumBitWords(RHS.size()); - Bits = new BitWord[Capacity]; - std::copy(RHS.Bits, &RHS.Bits[Capacity], Bits); + Bits = (BitWord *)std::malloc(Capacity * sizeof(BitWord)); + std::memcpy(Bits, RHS.Bits, Capacity * sizeof(BitWord)); + } + + BitVector(BitVector &&RHS) + : Bits(RHS.Bits), Size(RHS.Size), Capacity(RHS.Capacity) { + RHS.Bits = nullptr; + } + + ~BitVector() { + std::free(Bits); } + /// empty - Tests whether there are no bits in this bitvector. + bool empty() const { return Size == 0; } + /// size - Returns the number of bits in this bitvector. - unsigned size() const { return Size; } + size_type size() const { return Size; } /// count - Returns the number of bits which are set. - unsigned count() const { + size_type count() const { unsigned NumBits = 0; for (unsigned i = 0; i < NumBitWords(size()); ++i) - if (sizeof(BitWord) == 4) - NumBits += CountPopulation_32(Bits[i]); - else if (sizeof(BitWord) == 8) - NumBits += CountPopulation_64(Bits[i]); - else - assert(0 && "Unsupported!") + NumBits += countPopulation(Bits[i]); return NumBits; } @@ -110,6 +133,19 @@ public: return false; } + /// all - Returns true if all bits are set. + bool all() const { + for (unsigned i = 0; i < Size / BITWORD_SIZE; ++i) + if (Bits[i] != ~0UL) + return false; + + // If bits remain check that they are ones. The unused bits are always zero. + if (unsigned Remainder = Size % BITWORD_SIZE) + return Bits[Size / BITWORD_SIZE] == (1UL << Remainder) - 1; + + return true; + } + /// none - Returns true if none of the bits are set. bool none() const { return !any(); @@ -120,7 +156,7 @@ public: int find_first() const { for (unsigned i = 0; i < NumBitWords(size()); ++i) if (Bits[i] != 0) - return i * BITS_PER_WORD + CountTrailingZeros_32(Bits[i]); + return i * BITWORD_SIZE + countTrailingZeros(Bits[i]); return -1; } @@ -131,19 +167,19 @@ public: if (Prev >= Size) return -1; - unsigned WordPos = Prev / BITS_PER_WORD; - unsigned BitPos = Prev % BITS_PER_WORD; + unsigned WordPos = Prev / BITWORD_SIZE; + unsigned BitPos = Prev % BITWORD_SIZE; BitWord Copy = Bits[WordPos]; // Mask off previous bits. - Copy &= ~0 << BitPos; + Copy &= ~0UL << BitPos; if (Copy != 0) - return WordPos * BITS_PER_WORD + CountTrailingZeros_32(Copy); + return WordPos * BITWORD_SIZE + countTrailingZeros(Copy); // Check subsequent words. for (unsigned i = WordPos+1; i < NumBitWords(size()); ++i) if (Bits[i] != 0) - return i * BITS_PER_WORD + CountTrailingZeros_32(Bits[i]); + return i * BITWORD_SIZE + countTrailingZeros(Bits[i]); return -1; } @@ -154,18 +190,27 @@ public: /// resize - Grow or shrink the bitvector. void resize(unsigned N, bool t = false) { - if (N > Capacity * BITS_PER_WORD) { + if (N > Capacity * BITWORD_SIZE) { unsigned OldCapacity = Capacity; grow(N); init_words(&Bits[OldCapacity], (Capacity-OldCapacity), t); } + + // Set any old unused bits that are now included in the BitVector. This + // may set bits that are not included in the new vector, but we will clear + // them back out below. + if (N > Size) + set_unused_bits(t); + + // Update the size, and clear out any bits that are now unused + unsigned OldSize = Size; Size = N; - if (t) + if (t || N < OldSize) clear_unused_bits(); } void reserve(unsigned N) { - if (N > Capacity * BITS_PER_WORD) + if (N > Capacity * BITWORD_SIZE) grow(N); } @@ -177,7 +222,37 @@ public: } BitVector &set(unsigned Idx) { - Bits[Idx / BITS_PER_WORD] |= 1L << (Idx % BITS_PER_WORD); + assert(Bits && "Bits never allocated"); + Bits[Idx / BITWORD_SIZE] |= BitWord(1) << (Idx % BITWORD_SIZE); + return *this; + } + + /// set - Efficiently set a range of bits in [I, E) + BitVector &set(unsigned I, unsigned E) { + assert(I <= E && "Attempted to set backwards range!"); + assert(E <= size() && "Attempted to set out-of-bounds range!"); + + if (I == E) return *this; + + if (I / BITWORD_SIZE == E / BITWORD_SIZE) { + BitWord EMask = 1UL << (E % BITWORD_SIZE); + BitWord IMask = 1UL << (I % BITWORD_SIZE); + BitWord Mask = EMask - IMask; + Bits[I / BITWORD_SIZE] |= Mask; + return *this; + } + + BitWord PrefixMask = ~0UL << (I % BITWORD_SIZE); + Bits[I / BITWORD_SIZE] |= PrefixMask; + I = RoundUpToAlignment(I, BITWORD_SIZE); + + for (; I + BITWORD_SIZE <= E; I += BITWORD_SIZE) + Bits[I / BITWORD_SIZE] = ~0UL; + + BitWord PostfixMask = (1UL << (E % BITWORD_SIZE)) - 1; + if (I < E) + Bits[I / BITWORD_SIZE] |= PostfixMask; + return *this; } @@ -187,7 +262,36 @@ public: } BitVector &reset(unsigned Idx) { - Bits[Idx / BITS_PER_WORD] &= ~(1L << (Idx % BITS_PER_WORD)); + Bits[Idx / BITWORD_SIZE] &= ~(BitWord(1) << (Idx % BITWORD_SIZE)); + return *this; + } + + /// reset - Efficiently reset a range of bits in [I, E) + BitVector &reset(unsigned I, unsigned E) { + assert(I <= E && "Attempted to reset backwards range!"); + assert(E <= size() && "Attempted to reset out-of-bounds range!"); + + if (I == E) return *this; + + if (I / BITWORD_SIZE == E / BITWORD_SIZE) { + BitWord EMask = 1UL << (E % BITWORD_SIZE); + BitWord IMask = 1UL << (I % BITWORD_SIZE); + BitWord Mask = EMask - IMask; + Bits[I / BITWORD_SIZE] &= ~Mask; + return *this; + } + + BitWord PrefixMask = ~0UL << (I % BITWORD_SIZE); + Bits[I / BITWORD_SIZE] &= ~PrefixMask; + I = RoundUpToAlignment(I, BITWORD_SIZE); + + for (; I + BITWORD_SIZE <= E; I += BITWORD_SIZE) + Bits[I / BITWORD_SIZE] = 0UL; + + BitWord PostfixMask = (1UL << (E % BITWORD_SIZE)) - 1; + if (I < E) + Bits[I / BITWORD_SIZE] &= ~PostfixMask; + return *this; } @@ -199,37 +303,55 @@ public: } BitVector &flip(unsigned Idx) { - Bits[Idx / BITS_PER_WORD] ^= 1L << (Idx % BITS_PER_WORD); + Bits[Idx / BITWORD_SIZE] ^= BitWord(1) << (Idx % BITWORD_SIZE); return *this; } - // No argument flip. - BitVector operator~() const { - return BitVector(*this).flip(); - } - // Indexing. reference operator[](unsigned Idx) { + assert (Idx < Size && "Out-of-bounds Bit access."); return reference(*this, Idx); } bool operator[](unsigned Idx) const { - BitWord Mask = 1L << (Idx % BITS_PER_WORD); - return (Bits[Idx / BITS_PER_WORD] & Mask) != 0; + assert (Idx < Size && "Out-of-bounds Bit access."); + BitWord Mask = BitWord(1) << (Idx % BITWORD_SIZE); + return (Bits[Idx / BITWORD_SIZE] & Mask) != 0; } bool test(unsigned Idx) const { return (*this)[Idx]; } + /// Test if any common bits are set. + bool anyCommon(const BitVector &RHS) const { + unsigned ThisWords = NumBitWords(size()); + unsigned RHSWords = NumBitWords(RHS.size()); + for (unsigned i = 0, e = std::min(ThisWords, RHSWords); i != e; ++i) + if (Bits[i] & RHS.Bits[i]) + return true; + return false; + } + // Comparison operators. bool operator==(const BitVector &RHS) const { - if (Size != RHS.Size) - return false; - - for (unsigned i = 0; i < NumBitWords(size()); ++i) + unsigned ThisWords = NumBitWords(size()); + unsigned RHSWords = NumBitWords(RHS.size()); + unsigned i; + for (i = 0; i != std::min(ThisWords, RHSWords); ++i) if (Bits[i] != RHS.Bits[i]) return false; + + // Verify that any extra words are all zeros. + if (i != ThisWords) { + for (; i != ThisWords; ++i) + if (Bits[i]) + return false; + } else if (i != RHSWords) { + for (; i != RHSWords; ++i) + if (RHS.Bits[i]) + return false; + } return true; } @@ -237,101 +359,231 @@ public: return !(*this == RHS); } - // Intersection, union, disjoint union. - BitVector operator&=(const BitVector &RHS) { - assert(Size == RHS.Size && "Illegal operation!"); - for (unsigned i = 0; i < NumBitWords(size()); ++i) + /// Intersection, union, disjoint union. + BitVector &operator&=(const BitVector &RHS) { + unsigned ThisWords = NumBitWords(size()); + unsigned RHSWords = NumBitWords(RHS.size()); + unsigned i; + for (i = 0; i != std::min(ThisWords, RHSWords); ++i) Bits[i] &= RHS.Bits[i]; + + // Any bits that are just in this bitvector become zero, because they aren't + // in the RHS bit vector. Any words only in RHS are ignored because they + // are already zero in the LHS. + for (; i != ThisWords; ++i) + Bits[i] = 0; + return *this; } - BitVector operator|=(const BitVector &RHS) { - assert(Size == RHS.Size && "Illegal operation!"); - for (unsigned i = 0; i < NumBitWords(size()); ++i) + /// reset - Reset bits that are set in RHS. Same as *this &= ~RHS. + BitVector &reset(const BitVector &RHS) { + unsigned ThisWords = NumBitWords(size()); + unsigned RHSWords = NumBitWords(RHS.size()); + unsigned i; + for (i = 0; i != std::min(ThisWords, RHSWords); ++i) + Bits[i] &= ~RHS.Bits[i]; + return *this; + } + + /// test - Check if (This - RHS) is zero. + /// This is the same as reset(RHS) and any(). + bool test(const BitVector &RHS) const { + unsigned ThisWords = NumBitWords(size()); + unsigned RHSWords = NumBitWords(RHS.size()); + unsigned i; + for (i = 0; i != std::min(ThisWords, RHSWords); ++i) + if ((Bits[i] & ~RHS.Bits[i]) != 0) + return true; + + for (; i != ThisWords ; ++i) + if (Bits[i] != 0) + return true; + + return false; + } + + BitVector &operator|=(const BitVector &RHS) { + if (size() < RHS.size()) + resize(RHS.size()); + for (size_t i = 0, e = NumBitWords(RHS.size()); i != e; ++i) Bits[i] |= RHS.Bits[i]; return *this; } - BitVector operator^=(const BitVector &RHS) { - assert(Size == RHS.Size && "Illegal operation!"); - for (unsigned i = 0; i < NumBitWords(size()); ++i) + BitVector &operator^=(const BitVector &RHS) { + if (size() < RHS.size()) + resize(RHS.size()); + for (size_t i = 0, e = NumBitWords(RHS.size()); i != e; ++i) Bits[i] ^= RHS.Bits[i]; return *this; } - + // Assignment operator. const BitVector &operator=(const BitVector &RHS) { if (this == &RHS) return *this; Size = RHS.size(); unsigned RHSWords = NumBitWords(Size); - if (Size <= Capacity * BITS_PER_WORD) { - std::copy(RHS.Bits, &RHS.Bits[RHSWords], Bits); + if (Size <= Capacity * BITWORD_SIZE) { + if (Size) + std::memcpy(Bits, RHS.Bits, RHSWords * sizeof(BitWord)); clear_unused_bits(); return *this; } - + // Grow the bitvector to have enough elements. - Capacity = NumBitWords(Size); - BitWord *NewBits = new BitWord[Capacity]; - std::copy(RHS.Bits, &RHS.Bits[RHSWords], NewBits); + Capacity = RHSWords; + assert(Capacity > 0 && "negative capacity?"); + BitWord *NewBits = (BitWord *)std::malloc(Capacity * sizeof(BitWord)); + std::memcpy(NewBits, RHS.Bits, Capacity * sizeof(BitWord)); // Destroy the old bits. - delete[] Bits; + std::free(Bits); Bits = NewBits; return *this; } + const BitVector &operator=(BitVector &&RHS) { + if (this == &RHS) return *this; + + std::free(Bits); + Bits = RHS.Bits; + Size = RHS.Size; + Capacity = RHS.Capacity; + + RHS.Bits = nullptr; + + return *this; + } + + void swap(BitVector &RHS) { + std::swap(Bits, RHS.Bits); + std::swap(Size, RHS.Size); + std::swap(Capacity, RHS.Capacity); + } + + //===--------------------------------------------------------------------===// + // Portable bit mask operations. + //===--------------------------------------------------------------------===// + // + // These methods all operate on arrays of uint32_t, each holding 32 bits. The + // fixed word size makes it easier to work with literal bit vector constants + // in portable code. + // + // The LSB in each word is the lowest numbered bit. The size of a portable + // bit mask is always a whole multiple of 32 bits. If no bit mask size is + // given, the bit mask is assumed to cover the entire BitVector. + + /// setBitsInMask - Add '1' bits from Mask to this vector. Don't resize. + /// This computes "*this |= Mask". + void setBitsInMask(const uint32_t *Mask, unsigned MaskWords = ~0u) { + applyMask(Mask, MaskWords); + } + + /// clearBitsInMask - Clear any bits in this vector that are set in Mask. + /// Don't resize. This computes "*this &= ~Mask". + void clearBitsInMask(const uint32_t *Mask, unsigned MaskWords = ~0u) { + applyMask(Mask, MaskWords); + } + + /// setBitsNotInMask - Add a bit to this vector for every '0' bit in Mask. + /// Don't resize. This computes "*this |= ~Mask". + void setBitsNotInMask(const uint32_t *Mask, unsigned MaskWords = ~0u) { + applyMask(Mask, MaskWords); + } + + /// clearBitsNotInMask - Clear a bit in this vector for every '0' bit in Mask. + /// Don't resize. This computes "*this &= Mask". + void clearBitsNotInMask(const uint32_t *Mask, unsigned MaskWords = ~0u) { + applyMask(Mask, MaskWords); + } + private: unsigned NumBitWords(unsigned S) const { - return (S + BITS_PER_WORD-1) / BITS_PER_WORD; + return (S + BITWORD_SIZE-1) / BITWORD_SIZE; } - // Clear the unused top bits in the high word. - void clear_unused_bits() { - if (Size) { - unsigned ExtraBits = Size % BITS_PER_WORD; - Bits[Size / BITS_PER_WORD] &= ~(~0 << ExtraBits); + // Set the unused bits in the high words. + void set_unused_bits(bool t = true) { + // Set high words first. + unsigned UsedWords = NumBitWords(Size); + if (Capacity > UsedWords) + init_words(&Bits[UsedWords], (Capacity-UsedWords), t); + + // Then set any stray high bits of the last used word. + unsigned ExtraBits = Size % BITWORD_SIZE; + if (ExtraBits) { + BitWord ExtraBitMask = ~0UL << ExtraBits; + if (t) + Bits[UsedWords-1] |= ExtraBitMask; + else + Bits[UsedWords-1] &= ~ExtraBitMask; } } - void grow(unsigned NewSize) { - unsigned OldCapacity = Capacity; - Capacity = NumBitWords(NewSize); - BitWord *NewBits = new BitWord[Capacity]; + // Clear the unused bits in the high words. + void clear_unused_bits() { + set_unused_bits(false); + } - // Copy the old bits over. - if (OldCapacity != 0) - std::copy(Bits, &Bits[OldCapacity], NewBits); + void grow(unsigned NewSize) { + Capacity = std::max(NumBitWords(NewSize), Capacity * 2); + assert(Capacity > 0 && "realloc-ing zero space"); + Bits = (BitWord *)std::realloc(Bits, Capacity * sizeof(BitWord)); - // Destroy the old bits. - delete[] Bits; - Bits = NewBits; + clear_unused_bits(); } void init_words(BitWord *B, unsigned NumWords, bool t) { memset(B, 0 - (int)t, NumWords*sizeof(BitWord)); - } + } + + template + void applyMask(const uint32_t *Mask, unsigned MaskWords) { + static_assert(BITWORD_SIZE % 32 == 0, "Unsupported BitWord size."); + MaskWords = std::min(MaskWords, (size() + 31) / 32); + const unsigned Scale = BITWORD_SIZE / 32; + unsigned i; + for (i = 0; MaskWords >= Scale; ++i, MaskWords -= Scale) { + BitWord BW = Bits[i]; + // This inner loop should unroll completely when BITWORD_SIZE > 32. + for (unsigned b = 0; b != BITWORD_SIZE; b += 32) { + uint32_t M = *Mask++; + if (InvertMask) M = ~M; + if (AddBits) BW |= BitWord(M) << b; + else BW &= ~(BitWord(M) << b); + } + Bits[i] = BW; + } + for (unsigned b = 0; MaskWords; b += 32, --MaskWords) { + uint32_t M = *Mask++; + if (InvertMask) M = ~M; + if (AddBits) Bits[i] |= BitWord(M) << b; + else Bits[i] &= ~(BitWord(M) << b); + } + if (AddBits) + clear_unused_bits(); + } + +public: + /// Return the size (in bytes) of the bit vector. + size_t getMemorySize() const { return Capacity * sizeof(BitWord); } }; -inline BitVector operator&(const BitVector &LHS, const BitVector &RHS) { - BitVector Result(LHS); - Result &= RHS; - return Result; +static inline size_t capacity_in_bytes(const BitVector &X) { + return X.getMemorySize(); } -inline BitVector operator|(const BitVector &LHS, const BitVector &RHS) { - BitVector Result(LHS); - Result |= RHS; - return Result; -} +} // End llvm namespace -inline BitVector operator^(const BitVector &LHS, const BitVector &RHS) { - BitVector Result(LHS); - Result ^= RHS; - return Result; +namespace std { + /// Implement std::swap in terms of BitVector swap. + inline void + swap(llvm::BitVector &LHS, llvm::BitVector &RHS) { + LHS.swap(RHS); + } } - -} // End llvm namespace + #endif