| peephole (X.CMP (X.REG r, X.CONST 0w0)::l) = (X.TEST (X.REG r, X.REG r))::(peephole l)
| peephole ((X.JMP a)::(X.JMP b)::l) = peephole ((X.JMP a)::l) (* What the cock? Yes, we actually generate this. *)
| peephole ((X.JMP l1)::(X.LABEL l2)::l) = if (Label.compare (l1,l2) = EQUAL) then (X.LABEL l2)::(peephole l) else (X.JMP l1)::(X.LABEL l2)::(peephole l)
| peephole (X.CMP (X.REG r, X.CONST 0w0)::l) = (X.TEST (X.REG r, X.REG r))::(peephole l)
| peephole ((X.JMP a)::(X.JMP b)::l) = peephole ((X.JMP a)::l) (* What the cock? Yes, we actually generate this. *)
| peephole ((X.JMP l1)::(X.LABEL l2)::l) = if (Label.compare (l1,l2) = EQUAL) then (X.LABEL l2)::(peephole l) else (X.JMP l1)::(X.LABEL l2)::(peephole l)