[project @ 2005-02-10 13:01:52 by simonmar]

[ghc-hetmet.git] / ghc / compiler / stranal / WwLib.lhs

diff --git a/ghc/compiler/stranal/WwLib.lhs b/ghc/compiler/stranal/WwLib.lhs
index 58060b0..54a167d 100644 (file)
--- a/ghc/compiler/stranal/WwLib.lhs
+++ b/ghc/compiler/stranal/WwLib.lhs
@@ -20,7 +20,7 @@ import NewDemand      ( Demand(..), DmdResult(..), Demands(..) )
 import MkId            ( realWorldPrimId, voidArgId, mkRuntimeErrorApp, rUNTIME_ERROR_ID )
 import TysWiredIn      ( tupleCon )
 import Type            ( Type, isUnLiftedType, mkFunTys,
-                         splitForAllTys, splitFunTys, splitNewType_maybe, isAlgType
+                         splitForAllTys, splitFunTys, splitRecNewType_maybe, isAlgType
                        )
 import BasicTypes      ( Boxity(..) )
 import Var              ( Var, isId )
@@ -223,7 +223,7 @@ mkWWargs :: Type
                     Type)                      -- Type of wrapper body
 
 mkWWargs fun_ty demands one_shots
-  | Just rep_ty <- splitNewType_maybe fun_ty
+  | Just rep_ty <- splitRecNewType_maybe fun_ty
        -- The newtype case is for when the function has
        -- a recursive newtype after the arrow (rare)
        -- We check for arity >= 0 to avoid looping in the case
@@ -358,7 +358,7 @@ mkWWstr_one arg
        -- of dropping seqs in the worker
       Eval (Poly Abs)
        -> let
-               arg_w_unf = arg `setIdUnfolding` mkOtherCon []
+               arg_w_unf = arg `setIdUnfolding` evaldUnfolding
                -- Tell the worker arg that it's sure to be evaluated
                -- so that internal seqs can be dropped
           in
@@ -420,17 +420,22 @@ mkWWcpr body_ty RetCPR
 
     | n_con_args == 1 && isUnLiftedType con_arg_ty1
        -- Special case when there is a single result of unlifted type
+       --
+       -- Wrapper:     case (..call worker..) of x -> C x
+       -- Worker:      case (   ..body..    ) of C x -> x
     = getUniquesUs                     `thenUs` \ (work_uniq : arg_uniq : _) ->
       let
        work_wild = mk_ww_local work_uniq body_ty
        arg       = mk_ww_local arg_uniq  con_arg_ty1
        con_app   = mkConApp data_con (map Type tycon_arg_tys ++ [Var arg])
       in
-      returnUs (\ wkr_call -> Case wkr_call arg [(DEFAULT, [], con_app)],
-               \ body     -> workerCase body work_wild [(DataAlt data_con, [arg], Var arg)],
+      returnUs (\ wkr_call -> Case wkr_call arg (exprType con_app) [(DEFAULT, [], con_app)],
+               \ body     -> workerCase body work_wild con_arg_ty1 [(DataAlt data_con, [arg], Var arg)],
                con_arg_ty1)
 
     | otherwise                -- The general case
+       -- Wrapper: case (..call worker..) of (# a, b #) -> C a b
+       -- Worker:  case (   ...body...  ) of C a b -> (# a, b #)     
     = getUniquesUs             `thenUs` \ uniqs ->
       let
         (wrap_wild : work_wild : args) = zipWith mk_ww_local uniqs (ubx_tup_ty : body_ty : con_arg_tys)
@@ -440,8 +445,8 @@ mkWWcpr body_ty RetCPR
        ubx_tup_app                    = mkConApp ubx_tup_con (map Type con_arg_tys   ++ arg_vars)
         con_app                               = mkConApp data_con    (map Type tycon_arg_tys ++ arg_vars)
       in
-      returnUs (\ wkr_call -> Case wkr_call wrap_wild [(DataAlt ubx_tup_con, args, con_app)],
-               \ body     -> workerCase body work_wild [(DataAlt data_con,    args, ubx_tup_app)],
+      returnUs (\ wkr_call -> Case wkr_call wrap_wild (exprType con_app)  [(DataAlt ubx_tup_con, args, con_app)],
+               \ body     -> workerCase body work_wild ubx_tup_ty [(DataAlt data_con,    args, ubx_tup_app)],
                ubx_tup_ty)
     where
       (_, tycon_arg_tys, data_con, con_arg_tys) = splitProductType "mkWWcpr" body_ty
@@ -462,8 +467,8 @@ mkWWcpr body_ty other               -- No CPR info
 -- This transform doesn't move work or allocation
 -- from one cost centre to another
 
-workerCase (Note (SCC cc) e) arg alts = Note (SCC cc) (Case e arg alts)
-workerCase e                arg alts = Case e arg alts
+workerCase (Note (SCC cc) e) arg ty alts = Note (SCC cc) (Case e arg ty alts)
+workerCase e                arg ty alts = Case e arg ty alts
 \end{code}
 
 
@@ -489,9 +494,10 @@ mk_unpk_case arg unpk_args boxing_con boxing_tycon body
        -- A data type
   = Case (Var arg) 
         (sanitiseCaseBndr arg)
+         (exprType body)
         [(DataAlt boxing_con, unpk_args, body)]
 
-mk_seq_case arg body = Case (Var arg) (sanitiseCaseBndr arg) [(DEFAULT, [], body)]
+mk_seq_case arg body = Case (Var arg) (sanitiseCaseBndr arg) (exprType body) [(DEFAULT, [], body)]
 
 sanitiseCaseBndr :: Id -> Id
 -- The argument we are scrutinising has the right type to be