The constraints aren't currently checked by the front end, but the
code generator will fall over if they aren't satisfied.
-\begin{code}
-#ifdef DEBUG
-primOpInfo op = pprPanic "primOpInfo:" (ppr op)
-#endif
-\end{code}
-
%************************************************************************
%* *
\subsubsection[PrimOp-ool]{Which PrimOps are out-of-line}