WHLSL and MSL shader parameter/return types may differ in their layout — the stage_in parameters need to be flattened into a single struct for example — so shader entry points should unpack their parameters into the expected layout and when they exit they should repack into this format.
It might be easier to implement the packing/unpacking if we make a new function that represents the entry point that just does the packing/unpacking, the global struct, and the trap statement bool
Migrated to https://api.github.com/repos/gpuweb/WHLSL/issues/26
https://github.com/gpuweb/WHLSL/issues/26