protected internal OffHeapNumberArray(long length, int itemSize, long @base, MemoryAllocationTracker allocationTracker) : base(itemSize, @base)
{
UnsafeUtil.assertHasUnsafe();
this.LengthConflict = length;
this.AllocationTracker = allocationTracker;
long dataSize = length * itemSize;
bool itemSizeIsPowerOfTwo = Integer.bitCount(itemSize) == 1;
if (UnsafeUtil.allowUnalignedMemoryAccess || !itemSizeIsPowerOfTwo)
{
// we can end up here even if we require aligned memory access. Reason is that item size
// isn't power of two anyway and so we have to fallback to safer means of accessing the memory,
// i.e. byte for byte.
_allocatedBytes = dataSize;
this._allocatedAddress = this.Address = UnsafeUtil.allocateMemory(_allocatedBytes, allocationTracker);
}
else
{
// the item size is a power of two and we're required to access memory aligned
// so we can allocate a bit more to ensure we can get an aligned memory address to start from.
_allocatedBytes = dataSize + itemSize - 1;
this._allocatedAddress = UnsafeUtil.allocateMemory(_allocatedBytes, allocationTracker);
this.Address = UnsafeUtil.alignedMemory(_allocatedAddress, itemSize);
}
}
internal static long GetVictimPage(int pageSize, MemoryAllocationTracker allocationTracker)
{
lock (typeof(VictimPageReference))
{
if (_victimPageSize < pageSize)
{
// Note that we NEVER free any old victim pages. This is important because we cannot tell
// when we are done using them. Therefor, victim pages are allocated and stay allocated
// until our process terminates.
_victimPagePointer = UnsafeUtil.allocateMemory(pageSize, allocationTracker);
_victimPageSize = pageSize;
}
return(_victimPagePointer);
}
}
public override void Clear()
{
if (IsByteUniform(_defaultValue))
{
UnsafeUtil.setMemory(Address, LengthConflict * itemSize, _defaultValue[0]);
}
else
{
long intermediary = UnsafeUtil.allocateMemory(itemSize, AllocationTracker);
for (int i = 0; i < _defaultValue.Length; i++)
{
UnsafeUtil.putByte(intermediary + i, _defaultValue[i]);
}
for (long i = 0, adr = Address; i < LengthConflict; i++, adr += itemSize)
{
UnsafeUtil.copyMemory(intermediary, adr, itemSize);
}
UnsafeUtil.free(intermediary, itemSize, AllocationTracker);
}
}
