Implemented and fixed bugs in CmmInfo handling

[ghc-hetmet.git] / compiler / codeGen / ClosureInfo.lhs

diff --git a/compiler/codeGen/ClosureInfo.lhs b/compiler/codeGen/ClosureInfo.lhs
index 8f62bc7..db46368 100644 (file)
--- a/compiler/codeGen/ClosureInfo.lhs
+++ b/compiler/codeGen/ClosureInfo.lhs
@@ -13,8 +13,9 @@ the STG paper.
 
 \begin{code}
 module ClosureInfo (
-       ClosureInfo, LambdaFormInfo, SMRep,     -- all abstract
-       StandardFormInfo, 
+       ClosureInfo(..), LambdaFormInfo(..),    -- would be abstract but
+       StandardFormInfo(..),                   -- mkCmmInfo looks inside
+        SMRep,
 
        ArgDescr(..), Liveness(..), 
        C_SRT(..), needsSRT,
@@ -127,6 +128,10 @@ data C_SRT = NoC_SRT
 needsSRT :: C_SRT -> Bool
 needsSRT NoC_SRT       = False
 needsSRT (C_SRT _ _ _) = True
+
+instance Outputable C_SRT where
+  ppr (NoC_SRT) = ptext SLIT("_no_srt_")
+  ppr (C_SRT label off bitmap) = parens (ppr label <> comma <> ppr off <> comma <> text (show bitmap))
 \end{code}
 
 %************************************************************************
@@ -184,7 +189,7 @@ data LambdaFormInfo
 
 data ArgDescr
   = ArgSpec            -- Fits one of the standard patterns
-       !Int            -- RTS type identifier ARG_P, ARG_N, ...
+       !StgHalfWord    -- RTS type identifier ARG_P, ARG_N, ...
 
   | ArgGen             -- General case
        Liveness        -- Details about the arguments
@@ -257,12 +262,12 @@ mkLFThunk thunk_ty top fvs upd_flag
            (might_be_a_function thunk_ty)
 
 might_be_a_function :: Type -> Bool
+-- Return False only if we are *sure* it's a data type
+-- Look through newtypes etc as much as poss
 might_be_a_function ty
-  | Just (tc,_) <- splitTyConApp_maybe (repType ty), 
-    not (isFunTyCon tc)  && not (isAbstractTyCon tc) = False
-       -- don't forget to check for abstract types, which might
-       -- be functions too.
-  | otherwise = True
+  = case splitTyConApp_maybe (repType ty) of
+       Just (tc, _) -> not (isDataTyCon tc)
+       Nothing      -> True
 \end{code}
 
 @mkConLFInfo@ is similar, for constructors.
@@ -594,7 +599,13 @@ getCallMethod this_pkg name (LFThunk _ _ updatable std_form_info is_fun) n_args
         if we enter the same thunk multiple times, so the optimisation
         of jumping directly to the entry code is still valid.  --SDM
        -}
-  = ASSERT2( n_args == 0, ppr name ) EnterIt
+  = EnterIt
+    -- We used to have ASSERT( n_args == 0 ), but actually it is
+    -- possible for the optimiser to generate
+    --   let bot :: Int = error Int "urk"
+    --   in (bot `cast` unsafeCoerce Int (Int -> Int)) 3
+    -- This happens as a result of the case-of-error transformation
+    -- So the right thing to do is just to enter the thing
 
   | otherwise  -- Jump direct to code for single-entry thunks
   = ASSERT( n_args == 0 )
@@ -947,5 +958,3 @@ getTyDescription ty
 getPredTyDescription (ClassP cl tys) = getOccString cl
 getPredTyDescription (IParam ip ty)  = getOccString (ipNameName ip)
 \end{code}
-
-