internal DispatchCellInfo ConvertDispatchCellInfo(IntPtr module, DispatchCellInfo cellInfo)
{
using (LockHolder.Hold(_typeLoaderLock))
{
return ConvertDispatchCellInfo_Inner(
module,
cellInfo);
}
}
internal DispatchCellInfo ConvertDispatchCellInfo(NativeFormatModuleInfo module, DispatchCellInfo cellInfo)
{
using (LockHolder.Hold(_typeLoaderLock))
{
return ConvertDispatchCellInfo_Inner(
module,
cellInfo);
}
}
/// <summary>
/// Attempt to convert the dispatch cell to a metadata token to a more efficient vtable dispatch or interface/slot dispatch.
/// Failure to convert is not a correctness issue. We also support performing a dispatch based on metadata token alone.
/// </summary>
private static DispatchCellInfo ConvertDispatchCellInfo_Inner(NativeFormatModuleInfo module, DispatchCellInfo cellInfo)
{
Debug.Assert(cellInfo.CellType == DispatchCellType.MetadataToken);
TypeSystemContext context = TypeSystemContextFactory.Create();
MethodDesc targetMethod = context.ResolveMetadataUnit(module).GetMethod(cellInfo.MetadataToken.AsHandle(), null);
Debug.Assert(!targetMethod.HasInstantiation); // At this time we do not support generic virtuals through the dispatch mechanism
Debug.Assert(targetMethod.IsVirtual);
if (targetMethod.OwningType.IsInterface)
{
if (!LazyVTableResolver.TryGetInterfaceSlotNumberFromMethod(targetMethod, out cellInfo.InterfaceSlot))
{
// Unable to resolve interface method. Fail, by not mutating cellInfo
return(cellInfo);
}
if (!targetMethod.OwningType.RetrieveRuntimeTypeHandleIfPossible())
{
new TypeBuilder().BuildType(targetMethod.OwningType);
}
cellInfo.CellType = DispatchCellType.InterfaceAndSlot;
cellInfo.InterfaceType = targetMethod.OwningType.RuntimeTypeHandle.ToIntPtr();
cellInfo.MetadataToken = 0;
}
else
{
// Virtual function case, attempt to resolve to a VTable slot offset.
// If the offset is less than 4096 update the cellInfo
#if DEBUG
// The path of resolving a metadata token at dispatch time is relatively rare in practice.
// Force it to occur in debug builds with much more regularity
if ((s_ConvertDispatchCellInfoCounter % 16) == 0)
{
s_ConvertDispatchCellInfoCounter++;
TypeSystemContextFactory.Recycle(context);
return(cellInfo);
}
s_ConvertDispatchCellInfoCounter++;
#endif
int slotIndexOfMethod = LazyVTableResolver.VirtualMethodToSlotIndex(targetMethod);
int vtableOffset = -1;
if (slotIndexOfMethod >= 0)
{
vtableOffset = LazyVTableResolver.SlotIndexToEETypeVTableOffset(slotIndexOfMethod);
}
if ((vtableOffset < 4096) && (vtableOffset != -1))
{
cellInfo.CellType = DispatchCellType.VTableOffset;
cellInfo.VTableOffset = checked ((uint)vtableOffset);
cellInfo.MetadataToken = 0;
}
// Otherwise, do nothing, and resolve with a metadata dispatch later
}
TypeSystemContextFactory.Recycle(context);
return(cellInfo);
}
internal DispatchCellInfo ConvertDispatchCellInfo(IntPtr module, DispatchCellInfo cellInfo)
{
using (LockHolder.Hold(_typeLoaderLock))
{
return ConvertDispatchCellInfo_Inner(
module,
cellInfo);
}
}