Avoid GetFunctionForDelegate call in delegate vtables #1971
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…ing of the same vtable ptr for nullable support.
Sergio0694
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Apr 8, 2025
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Clever! Left just a couple notes 🙂
| { | ||
| IID = PIID, | ||
| Vtable = ABI.System.Nullable_Delegate<T>.AbiToProjectionVftablePtr | ||
| Vtable = ABI.System.Nullable_Delegate.AbiToProjectionVftablePtr |
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With this change, when will the generic vtable be used on NAOT? Could we drop that cctor? 🤔
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We might be able to drop it, but I will defer on that to future PR.
| } | ||
| } | ||
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| [Guid("61C17706-2D65-11E0-9AE8-D48564015472")] |
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What's the point of this guid and the one on the generic one? Each IReference<T> interface will have its own IID, so what does this one represent, and when is it used?
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This is actually not used, but represents IReference.
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Will remove this in future PR too.
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We saw when code mitigations are enabled to disable dynamic code,
GetFunctionPointerForDelegatewill run into issues. This is the first step to remove its usage specifically in delegate scenarios. We achieve this by using the same vtable for IReference which was the only scenario that needed it and instead as part of the shared implementation look up the registered IID which is the only reason why we couldn't share vtables before.