/// then the set is in 'small mode'.
const void **CurArray;
/// CurArraySize - The allocated size of CurArray, always a power of two.
+ /// Note that CurArray points to an array that has CurArraySize+1 elements in
+ /// it, so that the end iterator actually points to valid memory.
unsigned CurArraySize;
// If small, this is # elts allocated consecutively
SmallArray(SmallStorage), CurArray(SmallStorage), CurArraySize(SmallSize) {
assert(SmallSize && (SmallSize & (SmallSize-1)) == 0 &&
"Initial size must be a power of two!");
+ // The end pointer, always valid, is set to a valid element to help the
+ // iterator.
+ CurArray[SmallSize] = 0;
clear();
}
~SmallPtrSetImpl();
class SmallPtrSetIteratorImpl {
protected:
const void *const *Bucket;
- const void *const *End;
public:
- explicit SmallPtrSetIteratorImpl(const void *const *BP, const void*const *E)
- : Bucket(BP), End(E) {
- AdvanceIfNotValid();
+ explicit SmallPtrSetIteratorImpl(const void *const *BP) : Bucket(BP) {
+ AdvanceIfNotValid();
}
bool operator==(const SmallPtrSetIteratorImpl &RHS) const {
/// that is. This is guaranteed to stop because the end() bucket is marked
/// valid.
void AdvanceIfNotValid() {
- assert(Bucket <= End);
- while (Bucket != End &&
- (*Bucket == SmallPtrSetImpl::getEmptyMarker() ||
- *Bucket == SmallPtrSetImpl::getTombstoneMarker()))
+ while (*Bucket == SmallPtrSetImpl::getEmptyMarker() ||
+ *Bucket == SmallPtrSetImpl::getTombstoneMarker())
++Bucket;
}
};
typedef std::ptrdiff_t difference_type;
typedef std::forward_iterator_tag iterator_category;
- explicit SmallPtrSetIterator(const void *const *BP, const void *const *E)
- : SmallPtrSetIteratorImpl(BP, E) {}
+ explicit SmallPtrSetIterator(const void *const *BP)
+ : SmallPtrSetIteratorImpl(BP) {}
// Most methods provided by baseclass.
const PtrTy operator*() const {
- assert(Bucket < End);
return PtrTraits::getFromVoidPointer(const_cast<void*>(*Bucket));
}
class SmallPtrSet : public SmallPtrSetImpl {
// Make sure that SmallSize is a power of two, round up if not.
enum { SmallSizePowTwo = RoundUpToPowerOfTwo<SmallSize>::Val };
- /// SmallStorage - Fixed size storage used in 'small mode'.
- const void *SmallStorage[SmallSizePowTwo];
+ /// SmallStorage - Fixed size storage used in 'small mode'. The extra element
+ /// ensures that the end iterator actually points to valid memory.
+ const void *SmallStorage[SmallSizePowTwo+1];
typedef PointerLikeTypeTraits<PtrType> PtrTraits;
public:
SmallPtrSet() : SmallPtrSetImpl(SmallStorage, SmallSizePowTwo) {}
typedef SmallPtrSetIterator<PtrType> iterator;
typedef SmallPtrSetIterator<PtrType> const_iterator;
inline iterator begin() const {
- return iterator(CurArray, CurArray+CurArraySize);
+ return iterator(CurArray);
}
inline iterator end() const {
- return iterator(CurArray+CurArraySize, CurArray+CurArraySize);
+ return iterator(CurArray+CurArraySize);
}
// Allow assignment from any smallptrset with the same element type even if it