hash_lit (CmmLabel _) = 119 -- ugh
hash_lit (CmmLabelOff _ i) = cvt $ 199 + i
hash_lit (CmmLabelDiffOff _ _ i) = cvt $ 299 + i
hash_lit (CmmLabel _) = 119 -- ugh
hash_lit (CmmLabelOff _ i) = cvt $ 199 + i
hash_lit (CmmLabelDiffOff _ _ i) = cvt $ 299 + i