+ /// A "union" of an inline bucket array and the struct representing
+ /// a large bucket. This union will be discriminated by the 'Small' bit.
+ AlignedCharArrayUnion<BucketT[InlineBuckets], LargeRep> storage;
+
+public:
+ explicit SmallDenseMap(unsigned NumInitBuckets = 0) {
+ init(NumInitBuckets);
+ }
+
+ SmallDenseMap(const SmallDenseMap &other) {
+ init(0);
+ copyFrom(other);
+ }
+
+#if LLVM_USE_RVALUE_REFERENCES
+ SmallDenseMap(SmallDenseMap &&other) {
+ init(0);
+ swap(other);
+ }
+#endif
+
+ template<typename InputIt>
+ SmallDenseMap(const InputIt &I, const InputIt &E) {
+ init(NextPowerOf2(std::distance(I, E)));
+ this->insert(I, E);
+ }
+
+ ~SmallDenseMap() {
+ this->destroyAll();
+ deallocateBuckets();
+ }
+
+ void swap(SmallDenseMap& RHS) {
+ unsigned TmpNumEntries = RHS.NumEntries;
+ RHS.NumEntries = NumEntries;
+ NumEntries = TmpNumEntries;
+ std::swap(NumTombstones, RHS.NumTombstones);
+
+ const KeyT EmptyKey = this->getEmptyKey();
+ const KeyT TombstoneKey = this->getTombstoneKey();
+ if (Small && RHS.Small) {
+ // If we're swapping inline bucket arrays, we have to cope with some of
+ // the tricky bits of DenseMap's storage system: the buckets are not
+ // fully initialized. Thus we swap every key, but we may have
+ // a one-directional move of the value.
+ for (unsigned i = 0, e = InlineBuckets; i != e; ++i) {
+ BucketT *LHSB = &getInlineBuckets()[i],
+ *RHSB = &RHS.getInlineBuckets()[i];
+ bool hasLHSValue = (!KeyInfoT::isEqual(LHSB->first, EmptyKey) &&
+ !KeyInfoT::isEqual(LHSB->first, TombstoneKey));
+ bool hasRHSValue = (!KeyInfoT::isEqual(RHSB->first, EmptyKey) &&
+ !KeyInfoT::isEqual(RHSB->first, TombstoneKey));
+ if (hasLHSValue && hasRHSValue) {
+ // Swap together if we can...
+ std::swap(*LHSB, *RHSB);
+ continue;
+ }
+ // Swap separately and handle any assymetry.
+ std::swap(LHSB->first, RHSB->first);
+ if (hasLHSValue) {
+ new (&RHSB->second) ValueT(llvm_move(LHSB->second));
+ LHSB->second.~ValueT();
+ } else if (hasRHSValue) {
+ new (&LHSB->second) ValueT(llvm_move(RHSB->second));
+ RHSB->second.~ValueT();
+ }
+ }
+ return;
+ }
+ if (!Small && !RHS.Small) {
+ std::swap(getLargeRep()->Buckets, RHS.getLargeRep()->Buckets);
+ std::swap(getLargeRep()->NumBuckets, RHS.getLargeRep()->NumBuckets);
+ return;
+ }
+
+ SmallDenseMap &SmallSide = Small ? *this : RHS;
+ SmallDenseMap &LargeSide = Small ? RHS : *this;
+
+ // First stash the large side's rep and move the small side across.
+ LargeRep TmpRep = llvm_move(*LargeSide.getLargeRep());
+ LargeSide.getLargeRep()->~LargeRep();
+ LargeSide.Small = true;
+ // This is similar to the standard move-from-old-buckets, but the bucket
+ // count hasn't actually rotated in this case. So we have to carefully
+ // move construct the keys and values into their new locations, but there
+ // is no need to re-hash things.
+ for (unsigned i = 0, e = InlineBuckets; i != e; ++i) {
+ BucketT *NewB = &LargeSide.getInlineBuckets()[i],
+ *OldB = &SmallSide.getInlineBuckets()[i];
+ new (&NewB->first) KeyT(llvm_move(OldB->first));
+ OldB->first.~KeyT();
+ if (!KeyInfoT::isEqual(NewB->first, EmptyKey) &&
+ !KeyInfoT::isEqual(NewB->first, TombstoneKey)) {
+ new (&NewB->second) ValueT(llvm_move(OldB->second));
+ OldB->second.~ValueT();
+ }
+ }
+
+ // The hard part of moving the small buckets across is done, just move
+ // the TmpRep into its new home.
+ SmallSide.Small = false;
+ new (SmallSide.getLargeRep()) LargeRep(llvm_move(TmpRep));
+ }
+
+ SmallDenseMap& operator=(const SmallDenseMap& other) {
+ copyFrom(other);
+ return *this;
+ }
+
+#if LLVM_USE_RVALUE_REFERENCES
+ SmallDenseMap& operator=(SmallDenseMap &&other) {
+ this->destroyAll();
+ deallocateBuckets();
+ init(0);
+ swap(other);
+ return *this;
+ }
+#endif
+
+ void copyFrom(const SmallDenseMap& other) {
+ this->destroyAll();
+ deallocateBuckets();
+ Small = true;
+ if (other.getNumBuckets() > InlineBuckets) {
+ Small = false;
+ allocateBuckets(other.getNumBuckets());
+ }
+ this->BaseT::copyFrom(other);
+ }
+
+ void init(unsigned InitBuckets) {
+ Small = true;
+ if (InitBuckets > InlineBuckets) {
+ Small = false;
+ new (getLargeRep()) LargeRep(allocateBuckets(InitBuckets));
+ }
+ this->BaseT::initEmpty();
+ }
+
+ void grow(unsigned AtLeast) {
+ if (AtLeast > InlineBuckets)
+ AtLeast = std::max<unsigned>(64, NextPowerOf2(AtLeast));
+
+ if (Small) {
+ if (AtLeast <= InlineBuckets)
+ return; // Nothing to do.
+
+ // First move the inline buckets into a temporary storage.
+ AlignedCharArrayUnion<BucketT[InlineBuckets]> TmpStorage;
+ BucketT *TmpBegin = reinterpret_cast<BucketT *>(TmpStorage.buffer);
+ BucketT *TmpEnd = TmpBegin;
+
+ // Loop over the buckets, moving non-empty, non-tombstones into the
+ // temporary storage. Have the loop move the TmpEnd forward as it goes.
+ const KeyT EmptyKey = this->getEmptyKey();
+ const KeyT TombstoneKey = this->getTombstoneKey();
+ for (BucketT *P = getBuckets(), *E = P + InlineBuckets; P != E; ++P) {
+ if (!KeyInfoT::isEqual(P->first, EmptyKey) &&
+ !KeyInfoT::isEqual(P->first, TombstoneKey)) {
+ assert(size_t(TmpEnd - TmpBegin) < InlineBuckets &&
+ "Too many inline buckets!");
+ new (&TmpEnd->first) KeyT(llvm_move(P->first));
+ new (&TmpEnd->second) ValueT(llvm_move(P->second));
+ ++TmpEnd;
+ P->second.~ValueT();
+ }
+ P->first.~KeyT();
+ }
+
+ // Now make this map use the large rep, and move all the entries back
+ // into it.
+ Small = false;
+ new (getLargeRep()) LargeRep(allocateBuckets(AtLeast));
+ this->moveFromOldBuckets(TmpBegin, TmpEnd);
+ return;
+ }
+
+ LargeRep OldRep = llvm_move(*getLargeRep());
+ getLargeRep()->~LargeRep();
+ if (AtLeast <= InlineBuckets) {
+ Small = true;
+ } else {
+ new (getLargeRep()) LargeRep(allocateBuckets(AtLeast));
+ }
+
+ this->moveFromOldBuckets(OldRep.Buckets, OldRep.Buckets+OldRep.NumBuckets);
+
+ // Free the old table.
+ operator delete(OldRep.Buckets);
+ }
+
+ void shrink_and_clear() {
+ unsigned OldSize = this->size();
+ this->destroyAll();
+
+ // Reduce the number of buckets.
+ unsigned NewNumBuckets = 0;
+ if (OldSize) {
+ NewNumBuckets = 1 << (Log2_32_Ceil(OldSize) + 1);
+ if (NewNumBuckets > InlineBuckets && NewNumBuckets < 64u)
+ NewNumBuckets = 64;
+ }
+ if ((Small && NewNumBuckets <= InlineBuckets) ||
+ (!Small && NewNumBuckets == getLargeRep()->NumBuckets)) {
+ this->BaseT::initEmpty();
+ return;
+ }
+
+ deallocateBuckets();
+ init(NewNumBuckets);
+ }
+
+private:
+ unsigned getNumEntries() const {
+ return NumEntries;
+ }
+ void setNumEntries(unsigned Num) {
+ assert(Num < INT_MAX && "Cannot support more than INT_MAX entries");
+ NumEntries = Num;
+ }
+
+ unsigned getNumTombstones() const {
+ return NumTombstones;
+ }
+ void setNumTombstones(unsigned Num) {
+ NumTombstones = Num;
+ }
+
+ const BucketT *getInlineBuckets() const {
+ assert(Small);
+ // Note that this cast does not violate aliasing rules as we assert that
+ // the memory's dynamic type is the small, inline bucket buffer, and the
+ // 'storage.buffer' static type is 'char *'.
+ return reinterpret_cast<const BucketT *>(storage.buffer);
+ }
+ BucketT *getInlineBuckets() {
+ return const_cast<BucketT *>(
+ const_cast<const SmallDenseMap *>(this)->getInlineBuckets());
+ }
+ const LargeRep *getLargeRep() const {
+ assert(!Small);
+ // Note, same rule about aliasing as with getInlineBuckets.
+ return reinterpret_cast<const LargeRep *>(storage.buffer);
+ }
+ LargeRep *getLargeRep() {
+ return const_cast<LargeRep *>(
+ const_cast<const SmallDenseMap *>(this)->getLargeRep());
+ }
+
+ const BucketT *getBuckets() const {
+ return Small ? getInlineBuckets() : getLargeRep()->Buckets;
+ }
+ BucketT *getBuckets() {
+ return const_cast<BucketT *>(
+ const_cast<const SmallDenseMap *>(this)->getBuckets());
+ }
+ unsigned getNumBuckets() const {
+ return Small ? InlineBuckets : getLargeRep()->NumBuckets;
+ }
+
+ void deallocateBuckets() {
+ if (Small)
+ return;
+
+ operator delete(getLargeRep()->Buckets);
+ getLargeRep()->~LargeRep();
+ }
+
+ LargeRep allocateBuckets(unsigned Num) {
+ assert(Num > InlineBuckets && "Must allocate more buckets than are inline");
+ LargeRep Rep = {
+ static_cast<BucketT*>(operator new(sizeof(BucketT) * Num)), Num
+ };
+ return Rep;
+ }
+};
+
+template<typename KeyT, typename ValueT,
+ typename KeyInfoT, bool IsConst>
+class DenseMapIterator {
+ typedef std::pair<KeyT, ValueT> Bucket;
+ typedef DenseMapIterator<KeyT, ValueT,
+ KeyInfoT, true> ConstIterator;
+ friend class DenseMapIterator<KeyT, ValueT, KeyInfoT, true>;
+public:
+ typedef ptrdiff_t difference_type;
+ typedef typename conditional<IsConst, const Bucket, Bucket>::type value_type;
+ typedef value_type *pointer;
+ typedef value_type &reference;
+ typedef std::forward_iterator_tag iterator_category;
+private:
+ pointer Ptr, End;
+public:
+ DenseMapIterator() : Ptr(0), End(0) {}
+
+ DenseMapIterator(pointer Pos, pointer E, bool NoAdvance = false)
+ : Ptr(Pos), End(E) {
+ if (!NoAdvance) AdvancePastEmptyBuckets();
+ }
+
+ // If IsConst is true this is a converting constructor from iterator to
+ // const_iterator and the default copy constructor is used.
+ // Otherwise this is a copy constructor for iterator.
+ DenseMapIterator(const DenseMapIterator<KeyT, ValueT,
+ KeyInfoT, false>& I)
+ : Ptr(I.Ptr), End(I.End) {}
+
+ reference operator*() const {
+ return *Ptr;
+ }
+ pointer operator->() const {
+ return Ptr;
+ }
+
+ bool operator==(const ConstIterator &RHS) const {
+ return Ptr == RHS.operator->();
+ }
+ bool operator!=(const ConstIterator &RHS) const {
+ return Ptr != RHS.operator->();
+ }
+
+ inline DenseMapIterator& operator++() { // Preincrement
+ ++Ptr;
+ AdvancePastEmptyBuckets();
+ return *this;
+ }
+ DenseMapIterator operator++(int) { // Postincrement
+ DenseMapIterator tmp = *this; ++*this; return tmp;
+ }
+
+private:
+ void AdvancePastEmptyBuckets() {
+ const KeyT Empty = KeyInfoT::getEmptyKey();
+ const KeyT Tombstone = KeyInfoT::getTombstoneKey();
+
+ while (Ptr != End &&
+ (KeyInfoT::isEqual(Ptr->first, Empty) ||
+ KeyInfoT::isEqual(Ptr->first, Tombstone)))
+ ++Ptr;
+ }
+};
+
+template<typename KeyT, typename ValueT, typename KeyInfoT>
+static inline size_t
+capacity_in_bytes(const DenseMap<KeyT, ValueT, KeyInfoT> &X) {
+ return X.getMemorySize();
+}
+
+} // end namespace llvm