RuntimeMethodHandle.GetFunctionPointer() should check if generic method is constructed

[CyberAndrii]

Description

Calling GetFunctionPointer() on a non-constructed generic method throws InvalidProgramException: Common Language Runtime detected an invalid program. A more helpful error message could be added.

Reproduction Steps

unsafe
{
    var func = (delegate*<void>) typeof(Foo)
        .GetMethod(nameof(Foo.Func))!
        .MethodHandle
        .GetFunctionPointer();
    
    func();
}

static class Foo
{
    public static void Func<T>()
    {
    }
}

Expected behavior

User friendly exception is thrown.

Actual behavior

InvalidProgramException is thrown.

Unhandled exception. System.InvalidProgramException: Common Language Runtime detected an invalid program.
   at System.RuntimeMethodHandle.GetFunctionPointer() in /runtime/src/coreclr/System.Private.CoreLib/src/System/RuntimeHandles.cs:line 829
   at Program.<Main>$(String[] args)

Regression?

No

Known Workarounds

Not applicable

Configuration

.NET 8 and 9
linux-x64

Other information

If the type itself is a generic type it throws System.InvalidOperationException: Could not execute the method because either the method itself or the containing type is not fully instantiated.. I think that's the correct exception to be thrown.

unsafe
{
    var func = (delegate*<void>) typeof(Foo<>)
        .GetMethod("Func")!
        .MethodHandle
        .GetFunctionPointer();
    
    func();
}

static class Foo<T>
{
    public static void Func()
    {
    }
}

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