-- Why delete? Consider
-- let x = a*b in (x, \x -> x+3)
-- We add [x |-> a*b] to the substitution, but we must
- -- *delete* it from the substitution when going inside
+ -- _delete_ it from the substitution when going inside
-- the (\x -> ...)!
modifyInScope :: SimplEnv -> CoreBndr -> CoreBndr -> SimplEnv
-- in \y. ....case f of {...} ....
-- Here f is used just once, and duplicating the case work is fine (exprIsCheap).
-- But
--- * We can't preInlineUnconditionally because that woud invalidate
--- the occ info for b.
--- * We can't postInlineUnconditionally because the RHS is big, and
--- that risks exponential behaviour
--- * We can't call-site inline, because the rhs is big
+-- - We can't preInlineUnconditionally because that woud invalidate
+-- the occ info for b.
+-- - We can't postInlineUnconditionally because the RHS is big, and
+-- that risks exponential behaviour
+-- - We can't call-site inline, because the rhs is big
-- Alas!
where
; env1 <- go (zapFloats env_with_info) triples
; return (env0 `addRecFloats` env1) }
-- addFloats adds the floats from env1,
- -- *and* updates env0 with the in-scope set from env1
+ -- _and_ updates env0 with the in-scope set from env1
where
add_rules :: SimplEnv -> (InBndr,InExpr) -> (SimplEnv, (InBndr, OutBndr, InExpr))
-- Add the (substituted) rules to the binder