Relax argument checks on pinned GCHandles

[jkotas]

Relax argument checks on pinned GCHandles to allow any objects without references for consistency with DisableRuntimeMarshalling.

Fixes #68686

[ghost]

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Issue Details

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Relax argument checks on pinned GCHandles to allow any objects without references for consistency with DisableRuntimeMarshalling.

Fixes #68686

Author:	jkotas
Assignees:	-
Labels:	area-System.Runtime.InteropServices
Milestone:	-

[vargaz]

The mono changes look ok to me.

[AaronRobinsonMSFT]

It seems NativeAOT already has this similar definition and only checks for null or if the type has pointers. I think at this point there is really no argument against adding support in all cases.

runtime/src/coreclr/nativeaot/System.Private.CoreLib/src/System/Runtime/InteropServices/InteropExtensions.cs

Lines 15 to 32 in 8656518

	/// <summary>
	/// Hooks for System.Private.Interop.dll code to access internal functionality in System.Private.CoreLib.dll.
	///
	/// Methods added to InteropExtensions should also be added to the System.Private.CoreLib.InteropServices contract
	/// in order to be accessible from System.Private.Interop.dll.
	/// </summary>
	[CLSCompliant(false)]
	[ReflectionBlocked]
	public static class InteropExtensions
	{
	internal static bool MightBeBlittable(this EETypePtr eeType)
	{
	//
	// This is used as the approximate implementation of MethodTable::IsBlittable(). It will err in the direction of declaring
	// things blittable since it is used for argument validation only.
	//
	return !eeType.HasPointers;
	}

What about the following that mark char and bool as non-blittable? I think Crossgen or NativeAOT might trigger off of that in some manner.

runtime/src/coreclr/tools/Common/TypeSystem/Interop/IL/MarshalHelpers.cs

Lines 273 to 312 in 8656518

	case TypeFlags.Boolean:
	switch (nativeType)
	{
	case NativeTypeKind.Default:
	case NativeTypeKind.Boolean:
	return MarshallerKind.Bool;
	case NativeTypeKind.U1:
	case NativeTypeKind.I1:
	return MarshallerKind.CBool;
	case NativeTypeKind.VariantBool:
	if (context.Target.IsWindows)
	return MarshallerKind.VariantBool;
	else
	return MarshallerKind.Invalid;
	default:
	return MarshallerKind.Invalid;
	}
	case TypeFlags.Char:
	switch (nativeType)
	{
	case NativeTypeKind.I1:
	case NativeTypeKind.U1:
	return MarshallerKind.AnsiChar;
	case NativeTypeKind.I2:
	case NativeTypeKind.U2:
	return MarshallerKind.UnicodeChar;
	case NativeTypeKind.Default:
	if (isAnsi)
	return MarshallerKind.AnsiChar;
	else
	return MarshallerKind.UnicodeChar;
	default:
	return MarshallerKind.Invalid;
	}

[lambdageek]

Pinnable if it doesn't have references?

[jkotas]

What about the following that mark char and bool as non-blittable? I

I do not see a problem here. The marshaling without DisableRuntimeMarshaling needs work like it always did.

[AndyAyersMS]

Improvements on windows arm64: dotnet/perf-autofiling-issues#5147, dotnet/perf-autofiling-issues#5148