Yeah, I think this is the relevant bit: https://github.com/dotnet/coreclr/blob/master/Documentation/design-docs/GuardedDevirtualization.md https://github.com/do

Yeah, I think this is the relevant bit: https://github.com/dotnet/coreclr/blob/master/Documentation/design-docs/GuardedDevirtualization.md https://github.com/dotnet/coreclr/blob/master/Documentation/... Seems like they started trying speculative optimizations about six months ago. Speculative optimizations are not only the foundation of Graal but also of C2, BTW.