- '-fcse', # CSE must immediately follow a simplification pass, because it relies
- # on the no-shadowing invariant. See comments at the top of CSE.lhs
-
+ '-ffull-laziness', # nofib/spectral/hartel/wang doubles in speed if you
+ # do full laziness late in the day. It only happens
+ # after fusion and other stuff, so the early pass doesn't
+ # catch it. For the record, the redex is
+ # f_el22 (f_el21 r_midblock)
+
+ # We want CSE to follow the final full-laziness pass, because it may
+ # succeed in commoning up things floated out by full laziness.
+ #
+ # CSE must immediately follow a simplification pass, because it relies
+ # on the no-shadowing invariant. See comments at the top of CSE.lhs
+ # So it must NOT follow float-inwards, which can give rise to shadowing,
+ # even if its input doesn't have shadows. Hence putting it between
+ # the two passes.
+ '-fcse',
+
+