+ Check in compiler backend that nobody accidentally uses 64bit values on 32bit
systems
+ (MAYBE) Check that there aren't duplicate destinations in operand list?
+ Darn, the return type doesn't really work with 32bit systems, should fix that
somehow
+ Internally we currently expect all values to be doubles, but apparently
lightening doesn't automatically convert between the types when moving
parameters. Either we add in float operations and make sure the user knows which
type is being used when, or we add some filter that rewrites the floats to
doubles?