Initial SelectionDAG and stopping a MVT to be selected

Hi everyone,

I have defined a new machine value type for a specific target I’m working on. My question is, Is there a way that we can stop other targets from using this machine value type during the creation of the “initial SelectionDAG”? I know that this new value will never pass the legalization stage, but I want LLVM to never use this new MVT for other architectures apart from the one i’m working on.