emitPrimOp dflags [res] CtzOp   [w] = emitCtzCall res w (wordWidth dflags)
emitPrimOp dflags [res] CtzOp   [w] = emitCtzCall res w (wordWidth dflags)
emitPrimOp dflags [res] CtzOp   [w] = emitCtzCall res w (wordWidth dflags)