public static UnsafeHashSet *Allocate <T>(int capacity, bool fixedSize = false)
where T : unmanaged, IEquatable <T>
{
var valStride = sizeof(T);
var entryStride = sizeof(UnsafeHashCollection.Entry);
// round capacity up to next prime
capacity = UnsafeHashCollection.GetNextPrime(capacity);
var valAlignment = Memory.GetAlignment(valStride);
// the alignment for entry/key/val, we can't have less than ENTRY_ALIGNMENT
// bytes alignment because entries are 16 bytes with 1 x pointer + 2 x 4 byte integers
var alignment = Math.Max(UnsafeHashCollection.Entry.ALIGNMENT, valAlignment);
// calculate strides for all elements
valStride = Memory.RoundToAlignment(valStride, alignment);
entryStride = Memory.RoundToAlignment(sizeof(UnsafeHashCollection.Entry), alignment);
// dictionary ptr
UnsafeHashSet *set;
if (fixedSize)
{
var sizeOfHeader = Memory.RoundToAlignment(sizeof(UnsafeHashSet), alignment);
var sizeOfBucketsBuffer = Memory.RoundToAlignment(sizeof(UnsafeHashCollection.Entry * *) * capacity, alignment);
var sizeofEntriesBuffer = (entryStride + valStride) * capacity;
// allocate memory
var ptr = Memory.MallocAndZero(sizeOfHeader + sizeOfBucketsBuffer + sizeofEntriesBuffer, alignment);
// start of memory is the dict itself
set = (UnsafeHashSet *)ptr;
// buckets are offset by header size
set->_collection.Buckets = (UnsafeHashCollection.Entry * *)((byte *)ptr + sizeOfHeader);
// initialize fixed buffer
UnsafeBuffer.InitFixed(&set->_collection.Entries, (byte *)ptr + (sizeOfHeader + sizeOfBucketsBuffer), capacity, entryStride + valStride);
}
else
{
// allocate dict, buckets and entries buffer separately
set = Memory.MallocAndZero <UnsafeHashSet>();
set->_collection.Buckets = (UnsafeHashCollection.Entry * *)Memory.MallocAndZero(sizeof(UnsafeHashCollection.Entry * *) * capacity, sizeof(UnsafeHashCollection.Entry * *));
// init dynamic buffer
UnsafeBuffer.InitDynamic(&set->_collection.Entries, capacity, entryStride + valStride);
}
set->_collection.FreeCount = 0;
set->_collection.UsedCount = 0;
set->_collection.KeyOffset = entryStride;
set->_typeHandle = typeof(T).TypeHandle.Value;
return(set);
}
int _valueOffset; // Readonly
public static UnsafeDictionary *Allocate <K, V>(int capacity, bool fixedSize = false)
where K : unmanaged, IEquatable <K>
where V : unmanaged
{
var keyStride = sizeof(K);
var valStride = sizeof(V);
var entryStride = sizeof(UnsafeHashCollection.Entry);
// round capacity up to next prime
capacity = UnsafeHashCollection.GetNextPrime(capacity);
var keyAlignment = Memory.GetAlignment(keyStride);
var valAlignment = Memory.GetAlignment(valStride);
// the alignment for entry/key/val, we can't have less than ENTRY_ALIGNMENT
// bytes alignment because entries are 8 bytes with 2 x 32 bit integers
var alignment = Math.Max(UnsafeHashCollection.Entry.ALIGNMENT, Math.Max(keyAlignment, valAlignment));
// calculate strides for all elements
keyStride = Memory.RoundToAlignment(keyStride, alignment);
valStride = Memory.RoundToAlignment(valStride, alignment);
entryStride = Memory.RoundToAlignment(sizeof(UnsafeHashCollection.Entry), alignment);
// map ptr
UnsafeDictionary *map;
if (fixedSize)
{
var sizeOfHeader = Memory.RoundToAlignment(sizeof(UnsafeDictionary), alignment);
var sizeOfBucketsBuffer = Memory.RoundToAlignment(sizeof(UnsafeHashCollection.Entry * *) * capacity, alignment);
var sizeofEntriesBuffer = (entryStride + keyStride + valStride) * capacity;
// allocate memory
var ptr = Memory.MallocAndZero(sizeOfHeader + sizeOfBucketsBuffer + sizeofEntriesBuffer, alignment);
// start of memory is the dict itself
map = (UnsafeDictionary *)ptr;
// buckets are offset by header size
map->_collection.Buckets = (UnsafeHashCollection.Entry * *)((byte *)ptr + sizeOfHeader);
// initialize fixed buffer
UnsafeBuffer.InitFixed(&map->_collection.Entries, (byte *)ptr + (sizeOfHeader + sizeOfBucketsBuffer), capacity, entryStride + keyStride + valStride);
}
else
{
// allocate dict, buckets and entries buffer separately
map = Memory.MallocAndZero <UnsafeDictionary>();
map->_collection.Buckets = (UnsafeHashCollection.Entry * *)Memory.MallocAndZero(sizeof(UnsafeHashCollection.Entry * *) * capacity, sizeof(UnsafeHashCollection.Entry * *));
// init dynamic buffer
UnsafeBuffer.InitDynamic(&map->_collection.Entries, capacity, entryStride + keyStride + valStride);
}
// header init
map->_collection.FreeCount = 0;
map->_collection.UsedCount = 0;
map->_collection.KeyOffset = entryStride;
map->_typeHandleKey = typeof(K).TypeHandle.Value;
map->_typeHandleValue = typeof(V).TypeHandle.Value;
map->_valueOffset = entryStride + keyStride;
return(map);
}
