public static void Set(NumberSystem numberSystem)
{
var existing = _value;
if (existing == null)
{
switch (numberSystem)
{
case NumberSystem.Unsigned:
case NumberSystem.OnesComplement:
case NumberSystem.TwosComplement:
case NumberSystem.SignBit:
_value = numberSystem;
break;
default:
throw new ArgumentOutOfRangeException(nameof(numberSystem));
}
}
else if (numberSystem != existing.Value)
{
throw new InvalidOperationException($"The number-system for '{typeof(T).Name}' has already been set and cannot be changed");
}
}
private static void Sort32(Span<uint> keys, Span<uint> workspace, int r, uint keyMask, bool ascending, NumberSystem numberSystem)
{
if ((keyMask & SortUtils.MSB32U) == 0) numberSystem = NumberSystem.Unsigned;
if (!ascending || numberSystem != NumberSystem.Unsigned) throw new NotImplementedException("Need to do that!");
if (ascending ? SortUtils.ShortSortAscending(keys, 0, (uint)keys.Length) : SortUtils.ShortSortDescending(keys, 0, (uint)keys.Length))
{
r = SortUtils.ChooseBitCount<uint>(r, DefaultR);
workspace = workspace.Slice(0, keys.Length);
if (keyMask == 0) return;
Span<uint> offsets = stackalloc uint[1 << r];
int bucketCount = 1 << r, groups = ((32 - 1) / r) + 1;
uint mask = (uint)(bucketCount - 1), groupMask;
var shift = 32;
do
{
shift -= r;
groupMask = (keyMask >> shift) & mask;
keyMask &= ~(mask << shift);
} while (groupMask == 0);
// no need to check groupMask is non-zero - we already checked keyMask, so we definitely expect *something*
Sort32(keys, workspace, offsets, keyMask, groupMask, mask, r, shift, ascending, 0, keys.Length);
}
}
private static void Sort32(uint *keys, uint *workspace, int len, int r, uint keyMask, bool ascending, NumberSystem numberSystem)
{
if (len <= 1 || keyMask == 0)
{
return;
}
r = SortUtils.ChooseBitCount <uint>(r, DefaultR);
int countLength = 1 << r;
int groups = GroupCount <uint>(r);
uint *countsOffsets = stackalloc uint[countLength];
uint mask = (uint)(countLength - 1);
bool reversed = false;
if (SortCore32(keys, workspace, r, keyMask, countLength, len, countsOffsets, groups, mask, ascending, numberSystem != NumberSystem.Unsigned))
{
Swap(ref keys, ref workspace, ref reversed);
}
if (reversed)
{
Unsafe.CopyBlock(workspace, keys, (uint)len << 2);
}
}
