finished product unboxing through newtypes and proper demand analysis of newtypes

[ghc-hetmet.git] / compiler / simplCore / Simplify.lhs

diff --git a/compiler/simplCore/Simplify.lhs b/compiler/simplCore/Simplify.lhs
index 36e723d..85b4b49 100644 (file)
--- a/compiler/simplCore/Simplify.lhs
+++ b/compiler/simplCore/Simplify.lhs
@@ -611,7 +611,6 @@ completeLazyBind env top_lvl old_bndr new_bndr new_rhs
        -- means that we can avoid tests in exprIsConApp, for example.
        -- This is important: if exprIsConApp says 'yes' for a recursive
        -- thing, then we can get into an infinite loop
-
        -- If the unfolding is a value, the demand info may
        -- go pear-shaped, so we nuke it.  Example:
        --      let x = (a,b) in
@@ -814,9 +813,12 @@ simplCast env body co cont
            -- t2 :=: s2 with left and right on the curried form: 
            --    (->) t1 t2 :=: (->) s1 s2
            [co1, co2] = decomposeCo 2 co
-           new_arg    = mkCoerce (mkSymCoercion co1) (substExpr arg_env arg)
-           arg_env    = setInScope arg_se env
-           result     = ApplyTo dup new_arg (zapSubstEnv env) (addCoerce co2 cont)
+           new_arg    = mkCoerce (mkSymCoercion co1) arg'
+          arg'       = case arg_se of
+                         Nothing     -> arg
+                         Just arg_se -> substExpr (setInScope arg_se env) arg
+           result     = ApplyTo dup new_arg (Just $ zapSubstEnv env) 
+                               (addCoerce co2 cont)
        addCoerce co cont = CoerceIt co cont
     in
     simplType env co           `thenSmpl` \ co' ->
@@ -1517,6 +1519,7 @@ simplDefault :: SimplEnv
 
 simplDefault env case_bndr' imposs_cons cont Nothing
   = return []  -- No default branch
+
 simplDefault env case_bndr' imposs_cons cont (Just rhs)
   |    -- This branch handles the case where we are 
        -- scrutinisng an algebraic data type
@@ -1557,7 +1560,7 @@ simplDefault env case_bndr' imposs_cons cont (Just rhs)
 
        two_or_more -> simplify_default (map DataAlt gadt_imposs ++ imposs_cons)
 
-  | otherwise
+  | otherwise 
   = simplify_default imposs_cons
   where
     cant_match tys data_con = not (dataConCanMatch data_con tys)
@@ -1713,6 +1716,7 @@ knownCon env scrut con args bndr alts cont
                   simplNonRecX env bndr bndr_rhs               $ \ env ->
                   simplExprF env rhs cont
                where
+                  dead_bndr  = isDeadBinder bndr
                   n_drop_tys = tyConArity (dataConTyCon dc)
 
 -- Ugh!