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Fix up preallocated array to deallocate memory.

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I made a wrong assumption that the allocators would deallocate the
memory when their destructor was being called. Turns out this is not
true evidently.

Swift SVN r18753
This commit is contained in:
Michael Gottesman
2014-06-09 20:27:35 +00:00
parent afe7688b33
commit df5f9dbf6f
1 changed files with 25 additions and 21 deletions
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46
include/swift/Basic/PreallocatedArray.h
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@@ -14,45 +14,47 @@
#define SWIFT_BASIC_PREALLOCATEDARRAY_H_
#include "llvm/Support/Allocator.h"
#include "swift/Basic/NullablePtr.h"
#include <type_traits>
namespace swift {
/// An array meant for large collections of default constructible elements of
/// fixed size. It does one large allocation on construction.
template <typename EltTy, typename AllocatorTy=llvm::MallocAllocator>
template <typename EltTy, typename AllocatorTy = llvm::MallocAllocator>
class PreallocatedArray {
static_assert(std::is_default_constructible<EltTy>::value,
"EltTy must be default constructable.");
unsigned NumElts;
Optional<AllocatorTy> Allocator;
EltTy *Elt;
NullablePtr<AllocatorTy> Allocator;
EltTy *Elts;
public:
PreallocatedArray(unsigned NumElts)
: NumElts(NumElts),
Allocator(llvm::MallocAllocator()),
Elt(new (Allocator->template Allocate<EltTy>(NumElts)) EltTy[NumElts]) {}
: NumElts(NumElts), Allocator(new llvm::MallocAllocator()),
Elts(new (Allocator.get()->template Allocate<EltTy>(NumElts))
EltTy[NumElts]) {}
PreallocatedArray(unsigned NumElts, AllocatorTy &Allocator)
: NumElts(NumElts),
Elt(new (Allocator.template Allocate<EltTy>(NumElts)) EltTy[NumElts]) {}
PreallocatedArray(unsigned NumElts, AllocatorTy *InputAllocator)
: NumElts(NumElts), Allocator(InputAllocator),
Elts(new (Allocator.get()->template Allocate<EltTy>(NumElts)) EltTy[NumElts]) {
}
// Call destructors of data.
~PreallocatedArray() {
// Call destructors of data.
for (unsigned i = 0; i < NumElts; ++i) {
Elt[i].~EltTy();
Elts[i].~EltTy();
}
// And deallocate the memory.
Allocator.get()->template Deallocate<EltTy>(Elts, NumElts);
}
MutableArrayRef<EltTy> getArray() {
return MutableArrayRef<EltTy>(Elt, NumElts);
return MutableArrayRef<EltTy>(Elts, NumElts);
}
ArrayRef<EltTy> getArray() const {
return ArrayRef<EltTy>(Elt, NumElts);
}
ArrayRef<EltTy> getArray() const { return ArrayRef<EltTy>(Elts, NumElts); }
using iterator = typename MutableArrayRef<EltTy>::iterator;
using const_iterator = typename ArrayRef<EltTy>::iterator;
@@ -63,13 +65,15 @@ public:
const_iterator begin() const { return getArray().begin(); }
const_iterator end() const { return getArray().end(); }
Range<iterator> getRange() { return {begin(), end()}; }
Range<const_iterator> getRange() const { return {begin(), end()}; }
Range<iterator> getRange() {
return {begin(), end()};
}
Range<const_iterator> getRange() const {
return {begin(), end()};
}
unsigned size() const { return NumElts; }
EltTy &operator[](size_t Index) {
return getArray()[Index];
}
EltTy &operator[](size_t Index) { return getArray()[Index]; }
};
} // end namespace swift