import Maybes ( orElse )
import Data.List ( mapAccumL )
import Outputable
-import MonadUtils
import FastString
\end{code}
do { tick LetFloatFromLet
; (poly_binds, body3) <- abstractFloats tvs' body_env2 body2
; rhs' <- mkLam tvs' body3
- ; env' <- foldlM add_poly_bind env poly_binds
+ ; let env' = foldl (addPolyBind top_lvl) env poly_binds
; return (env', rhs') }
; completeBind env' top_lvl bndr bndr1 rhs' }
- where
- add_poly_bind env (NonRec poly_id rhs)
- = completeBind env top_lvl poly_id poly_id rhs
- -- completeBind adds the new binding in the
- -- proper way (ie complete with unfolding etc),
- -- and extends the in-scope set
- add_poly_bind env bind@(Rec _)
- = return (extendFloats env bind)
- -- Hack: letrecs are more awkward, so we extend "by steam"
- -- without adding unfoldings etc. At worst this leads to
- -- more simplifier iterations
\end{code}
A specialised variant of simplNonRec used when the RHS is already simplified,
-- Use the substitution to make quite, quite sure that the
-- substitution will happen, since we are going to discard the binding
- | otherwise
- = let
+ | otherwise
+ = return (addNonRecWithUnf env new_bndr new_rhs unfolding wkr)
+ where
+ unfolding | omit_unfolding = NoUnfolding
+ | otherwise = mkUnfolding (isTopLevel top_lvl) new_rhs
+ old_info = idInfo old_bndr
+ occ_info = occInfo old_info
+ wkr = substWorker env (workerInfo old_info)
+ omit_unfolding = isNonRuleLoopBreaker occ_info || not (activeInline env old_bndr)
+
+-----------------
+addPolyBind :: TopLevelFlag -> SimplEnv -> OutBind -> SimplEnv
+-- Add a new binding to the environment, complete with its unfolding
+-- but *do not* do postInlineUnconditionally, because we have already
+-- processed some of the scope of the binding
+-- We still want the unfolding though. Consider
+-- let
+-- x = /\a. let y = ... in Just y
+-- in body
+-- Then we float the y-binding out (via abstractFloats and addPolyBind)
+-- but 'x' may well then be inlined in 'body' in which case we'd like the
+-- opportunity to inline 'y' too.
+
+addPolyBind top_lvl env (NonRec poly_id rhs)
+ = addNonRecWithUnf env poly_id rhs unfolding NoWorker
+ where
+ unfolding | not (activeInline env poly_id) = NoUnfolding
+ | otherwise = mkUnfolding (isTopLevel top_lvl) rhs
+ -- addNonRecWithInfo adds the new binding in the
+ -- proper way (ie complete with unfolding etc),
+ -- and extends the in-scope set
+
+addPolyBind _ env bind@(Rec _) = extendFloats env bind
+ -- Hack: letrecs are more awkward, so we extend "by steam"
+ -- without adding unfoldings etc. At worst this leads to
+ -- more simplifier iterations
+
+-----------------
+addNonRecWithUnf :: SimplEnv
+ -> OutId -> OutExpr -- New binder and RHS
+ -> Unfolding -> WorkerInfo -- and unfolding
+ -> SimplEnv
+-- Add suitable IdInfo to the Id, add the binding to the floats, and extend the in-scope set
+addNonRecWithUnf env new_bndr rhs unfolding wkr
+ = final_id `seq` -- This seq forces the Id, and hence its IdInfo,
+ -- and hence any inner substitutions
+ addNonRec env final_id rhs
+ -- The addNonRec adds it to the in-scope set too
+ where
-- Arity info
- new_bndr_info = idInfo new_bndr `setArityInfo` exprArity new_rhs
+ new_bndr_info = idInfo new_bndr `setArityInfo` exprArity rhs
-- Unfolding info
-- Add the unfolding *only* for non-loop-breakers
-- (for example) be no longer strictly demanded.
-- The solution here is a bit ad hoc...
info_w_unf = new_bndr_info `setUnfoldingInfo` unfolding
- `setWorkerInfo` worker_info
+ `setWorkerInfo` wkr
- final_info | omit_unfolding = new_bndr_info
- | isEvaldUnfolding unfolding = zapDemandInfo info_w_unf `orElse` info_w_unf
+ final_info | isEvaldUnfolding unfolding = zapDemandInfo info_w_unf `orElse` info_w_unf
| otherwise = info_w_unf
-
+
final_id = new_bndr `setIdInfo` final_info
- in
- -- These seqs forces the Id, and hence its IdInfo,
- -- and hence any inner substitutions
- final_id `seq`
- -- pprTrace "Binding" (ppr final_id <+> ppr unfolding) $
- return (addNonRec env final_id new_rhs)
- -- The addNonRec adds it to the in-scope set too
- where
- unfolding = mkUnfolding (isTopLevel top_lvl) new_rhs
- worker_info = substWorker env (workerInfo old_info)
- omit_unfolding = isNonRuleLoopBreaker occ_info || not (activeInline env old_bndr)
- old_info = idInfo old_bndr
- occ_info = occInfo old_info
\end{code}
join_rhs = mkLams really_final_bndrs rhs'
join_call = mkApps (Var join_bndr) final_args
- ; return (addNonRec env join_bndr join_rhs, (con, bndrs', join_call)) }
+ ; return (addPolyBind NotTopLevel env (NonRec join_bndr join_rhs), (con, bndrs', join_call)) }
-- See Note [Duplicated env]
\end{code}
projects / ghc-hetmet.git / blobdiff