[project @ 2003-06-03 09:41:48 by ross]

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

diff --git a/ghc/compiler/stranal/WwLib.lhs b/ghc/compiler/stranal/WwLib.lhs
index b182028..49571f3 100644 (file)
--- a/ghc/compiler/stranal/WwLib.lhs
+++ b/ghc/compiler/stranal/WwLib.lhs
@@ -17,16 +17,15 @@ import Id           ( Id, idType, mkSysLocal, idNewDemandInfo, setIdNewDemandInfo,
 import IdInfo          ( vanillaIdInfo )
 import DataCon         ( splitProductType_maybe, splitProductType )
 import NewDemand       ( Demand(..), DmdResult(..), Demands(..) ) 
-import MkId            ( realWorldPrimId, voidArgId, eRROR_CSTRING_ID )
+import MkId            ( realWorldPrimId, voidArgId, mkRuntimeErrorApp, rUNTIME_ERROR_ID )
 import TysWiredIn      ( tupleCon )
 import Type            ( Type, isUnLiftedType, mkFunTys,
                          splitForAllTys, splitFunTys, splitNewType_maybe, isAlgType
                        )
-import Literal         ( Literal(MachStr) )
 import BasicTypes      ( Boxity(..) )
 import Var              ( Var, isId )
 import UniqSupply      ( returnUs, thenUs, getUniquesUs, UniqSM )
-import Util            ( zipWithEqual )
+import Util            ( zipWithEqual, notNull )
 import Outputable
 import List            ( zipWith4 )
 \end{code}
@@ -241,11 +240,11 @@ mkWWargs fun_ty demands one_shots
              work_fn_args . Note (Coerce rep_ty fun_ty),
              res_ty)
 
-  | not (null demands)
+  | notNull demands
   = getUniquesUs               `thenUs` \ wrap_uniqs ->
     let
-      (tyvars, tau)            = splitForAllTys fun_ty
-      (arg_tys, body_ty)       = splitFunTys tau
+      (tyvars, tau)      = splitForAllTys fun_ty
+      (arg_tys, body_ty) = splitFunTys tau
 
       n_demands        = length demands
       n_arg_tys        = length arg_tys
@@ -258,7 +257,7 @@ mkWWargs fun_ty demands one_shots
       val_args = zipWith4 mk_wrap_arg wrap_uniqs arg_tys demands one_shots
       wrap_args = tyvars ++ val_args
     in
-{-     ASSERT( not (null tyvars) || not (null arg_tys) ) -}
+{-     ASSERT( notNull tyvars || notNull arg_tys ) -}
     if (null tyvars) && (null arg_tys) then
        pprTrace "mkWWargs" (ppr fun_ty $$ ppr demands) 
                returnUs ([], id, id, fun_ty)
@@ -281,7 +280,7 @@ applyToVars :: [Var] -> CoreExpr -> CoreExpr
 applyToVars vars fn = mkVarApps fn vars
 
 mk_wrap_arg uniq ty dmd one_shot 
-  = set_one_shot one_shot (setIdNewDemandInfo (mkSysLocal SLIT("w") uniq ty) dmd)
+  = set_one_shot one_shot (setIdNewDemandInfo (mkSysLocal FSLIT("w") uniq ty) dmd)
   where
     set_one_shot True  id = setOneShotLambda id
     set_one_shot False id = id
@@ -421,6 +420,9 @@ 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
@@ -432,6 +434,8 @@ mkWWcpr body_ty RetCPR
                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)
@@ -441,7 +445,7 @@ 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)],
+      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)],
                ubx_tup_ty)
     where
@@ -483,8 +487,7 @@ mk_absent_let arg body
   = panic "WwLib: haven't done mk_absent_let for primitives yet"
   where
     arg_ty = idType arg
---    abs_rhs = mkTyApps (Var aBSENT_ERROR_ID) [arg_ty]
-    abs_rhs = mkApps (Var eRROR_CSTRING_ID) [Type arg_ty, Lit (MachStr (_PK_ msg))] 
+    abs_rhs = mkRuntimeErrorApp rUNTIME_ERROR_ID arg_ty msg
     msg     = "Oops!  Entered absent arg " ++ showSDocDebug (ppr arg <+> ppr (idType arg))
 
 mk_unpk_case arg unpk_args boxing_con boxing_tycon body
@@ -506,5 +509,5 @@ sanitiseCaseBndr :: Id -> Id
 -- like                (x+y) `seq` ....
 sanitiseCaseBndr id = id `setIdInfo` vanillaIdInfo
 
-mk_ww_local uniq ty = mkSysLocal SLIT("ww") uniq ty
+mk_ww_local uniq ty = mkSysLocal FSLIT("ww") uniq ty
 \end{code}