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// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
#include "growablebitvector.h"
#include <cassert>
/////////////////////////////////
namespace search {
using vespalib::GenerationHeldBase;
using vespalib::GenerationHolder;
namespace {
struct GenerationHeldAllocatedBitVector : public vespalib::GenerationHeldBase {
std::unique_ptr<AllocatedBitVector> vector;
GenerationHeldAllocatedBitVector(std::unique_ptr<AllocatedBitVector> vector_in)
: GenerationHeldBase(sizeof(AllocatedBitVector) + vector_in->extraByteSize()),
vector(std::move(vector_in)) {}
};
}
GenerationHeldBase::UP
GrowableBitVector::grow(BitWord::Index newSize, BitWord::Index newCapacity)
{
AllocatedBitVector &self = *_stored;
assert(newCapacity >= newSize);
if (newCapacity != self.capacity()) {
auto tbv = std::make_unique<AllocatedBitVector>(newSize, newCapacity, self._alloc.get(), self.size(), &self._alloc);
if (newSize > self.size()) {
tbv->clear_bit_and_maintain_count_no_range_check(self.size()); // Clear old guard bit.
}
auto to_hold = std::make_unique<GenerationHeldAllocatedBitVector>(std::move(_stored));
_self.store(tbv.get(), std::memory_order_release);
_stored = std::move(tbv);
return to_hold;
} else {
if (newSize > self.size()) {
BitVector::Range clearRange(self.size(), newSize);
self.setSize(newSize);
self.clearIntervalNoInvalidation(clearRange);
} else {
self.clearIntervalNoInvalidation(BitVector::Range(newSize, self.size()));
self.setSize(newSize);
self.updateCount();
}
}
return {};
}
GrowableBitVector::GrowableBitVector(BitWord::Index newSize, BitWord::Index newCapacity,
GenerationHolder &generationHolder,
const Alloc *init_alloc)
: _stored(std::make_unique<AllocatedBitVector>(newSize, newCapacity, nullptr, 0, init_alloc)),
_self(_stored.get()),
_generationHolder(generationHolder)
{
assert(newSize <= newCapacity);
}
bool
GrowableBitVector::reserve(BitWord::Index newCapacity)
{
BitWord::Index oldCapacity = _stored->capacity();
assert(newCapacity >= oldCapacity);
if (newCapacity == oldCapacity)
return false;
return hold(grow(_stored->size(), newCapacity));
}
bool
GrowableBitVector::hold(GenerationHeldBase::UP v)
{
if (v) {
_generationHolder.insert(std::move(v));
return true;
}
return false;
}
bool
GrowableBitVector::shrink(BitWord::Index newCapacity)
{
BitWord::Index oldCapacity = _stored->capacity();
assert(newCapacity <= oldCapacity);
(void) oldCapacity;
return hold(grow(newCapacity, std::max(_stored->capacity(), newCapacity)));
}
bool
GrowableBitVector::extend(BitWord::Index newCapacity)
{
return hold(grow(newCapacity, std::max(_stored->capacity(), newCapacity)));
}
} // namespace search
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