public VMStack(VMHeap heap, int stackSize)
{
// stupid hack: to unify pointer logic, we allocate the stack from our VM heap too
_heap = heap;
_stackAlloc = heap.Get(heap.malloc(null, stackSize));
heap.Pin(_stackAlloc.Handle);
_mem = _stackAlloc.Memory;
_ptr = 0;
}
private unsafe void Scan(MemorySpan mem, int offset, TypeInfo type)
{
if (type is StructTypeInfo structType)
{
foreach (var f in structType.Fields)
{
Scan(mem, offset + f.FieldOffset, f.FieldType);
}
}
else if (type is DynamicArrayTypeInfo dynamicArrayType)
{
// grab pointer to array and then scan it
using (var handle = mem.Pin(offset))
{
uint ptr = *((uint *)handle.Ptr);
ScanArray(ptr, dynamicArrayType);
}
}
else if (type is ReferenceTypeInfo referenceType)
{
// grab pointer and then scan it
using (var handle = mem.Pin(offset))
{
uint ptr = *((uint *)handle.Ptr);
Scan(ptr);
}
}
else if (type is StringTypeInfo stringType)
{
// grab pointer and then scan it
using (var handle = mem.Pin(offset))
{
uint ptr = *((uint *)handle.Ptr);
if (ptr != 0)
{
Get(ptr).Mark = true;
}
}
}
else if (type is StaticArrayTypeInfo staticArrayType)
{
int elemOffset = 0;
for (int i = 0; i < staticArrayType.ArraySize; i++)
{
Scan(mem, offset + elemOffset, staticArrayType.ElementType);
elemOffset += staticArrayType.ElementType.SizeOf();
}
}
}
public void Free(MemorySpan span)
{
// don't need to free memory, the .NET GC will handle it
}
