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

diff --git a/compiler/simplCore/SimplUtils.lhs b/compiler/simplCore/SimplUtils.lhs
index d697fb3..53c9149 100644 (file)
--- a/compiler/simplCore/SimplUtils.lhs
+++ b/compiler/simplCore/SimplUtils.lhs
@@ -10,12 +10,12 @@ module SimplUtils (
 
        -- Inlining,
        preInlineUnconditionally, postInlineUnconditionally, 
-       activeInline, activeRule, inlineMode,
+       activeInline, activeRule, 
 
        -- The continuation type
        SimplCont(..), DupFlag(..), ArgInfo(..),
        contIsDupable, contResultType, contIsTrivial, contArgs, dropArgs, 
-       countValArgs, countArgs, splitInlineCont,
+       countValArgs, countArgs, 
        mkBoringStop, mkLazyArgStop, contIsRhsOrArg,
        interestingCallContext, interestingArgContext,
 
@@ -214,24 +214,6 @@ dropArgs :: Int -> SimplCont -> SimplCont
 dropArgs 0 cont = cont
 dropArgs n (ApplyTo _ _ _ cont) = dropArgs (n-1) cont
 dropArgs n other               = pprPanic "dropArgs" (ppr n <+> ppr other)
-
---------------------
-splitInlineCont :: SimplCont -> Maybe (SimplCont, SimplCont)
--- Returns Nothing if the continuation should dissolve an InlineMe Note
--- Return Just (c1,c2) otherwise, 
---     where c1 is the continuation to put inside the InlineMe 
---     and   c2 outside
-
--- Example: (__inline_me__ (/\a. e)) ty
---     Here we want to do the beta-redex without dissolving the InlineMe
--- See test simpl017 (and Trac #1627) for a good example of why this is important
-
-splitInlineCont (ApplyTo dup (Type ty) se c)
-  | Just (c1, c2) <- splitInlineCont c = Just (ApplyTo dup (Type ty) se c1, c2)
-splitInlineCont cont@(Stop {})         = Just (mkBoringStop, cont)
-splitInlineCont cont@(StrictBind {})   = Just (mkBoringStop, cont)
-splitInlineCont cont@(StrictArg  {})   = Just (mkBoringStop, cont)
-splitInlineCont _                      = Nothing
 \end{code}
 
 
@@ -308,17 +290,17 @@ interestingCallContext :: SimplCont -> CallCtxt
 interestingCallContext cont
   = interesting cont
   where
-    interestingCtxt = ArgCtxt False 2  -- Give *some* incentive!
-
     interesting (Select _ bndr _ _ _)
-       | isDeadBinder bndr       = CaseCtxt
-       | otherwise               = interestingCtxt
+       | isDeadBinder bndr = CaseCtxt
+       | otherwise         = ArgCtxt False 2   -- If the binder is used, this
+                                               -- is like a strict let
                
-    interesting (ApplyTo {})      = interestingCtxt
-                               -- Can happen if we have (coerce t (f x)) y
-                               -- Perhaps interestingCtxt is a bit over-keen, but I've
-                               -- seen (coerce f) x, where f has an INLINE prag,
-                               -- So we have to give some motivation for inlining it
+    interesting (ApplyTo _ arg _ cont)
+       | isTypeArg arg = interesting cont
+       | otherwise     = ValAppCtxt    -- Can happen if we have (f Int |> co) y
+                                       -- If f has an INLINE prag we need to give it some
+                                       -- motivation to inline. See Note [Cast then apply]
+                                       -- in CoreUnfold
 
     interesting (StrictArg _ cci _ _)  = cci
     interesting (StrictBind {})                = BoringCtxt
@@ -359,7 +341,7 @@ mkArgInfo fun n_val_args call_cont
     vanilla_discounts, arg_discounts :: [Int]
     vanilla_discounts = repeat 0
     arg_discounts = case idUnfolding fun of
-                       CoreUnfolding _ _ _ _ (UnfoldIfGoodArgs _ discounts _ _)
+                       CoreUnfolding {uf_guidance = UnfoldIfGoodArgs {ug_args = discounts}}
                              -> discounts ++ vanilla_discounts
                        _     -> vanilla_discounts
 
@@ -480,13 +462,7 @@ unboxed tuples and suchlike.
 
 INLINE pragmas
 ~~~~~~~~~~~~~~
-SimplGently is also used as the mode to simplify inside an InlineMe note.
-
-\begin{code}
-inlineMode :: SimplifierMode
-inlineMode = SimplGently
-\end{code}
-
+We don't simplify inside InlineRules (which come from INLINE pragmas).
 It really is important to switch off inlinings inside such
 expressions.  Consider the following example 
 
@@ -1438,9 +1414,9 @@ prepareDefault _ _ case_bndr (Just (tycon, inst_tys)) imposs_cons (Just deflt_rh
 
        _ -> return [(DEFAULT, [], deflt_rhs)]
 
-  | debugIsOn, isAlgTyCon tycon, [] <- tyConDataCons tycon
+  | debugIsOn, isAlgTyCon tycon, not (isOpenTyCon tycon), null (tyConDataCons tycon)
+       -- This can legitimately happen for type families, so don't report that
   = pprTrace "prepareDefault" (ppr case_bndr <+> ppr tycon)
-       -- This can legitimately happen for type families
         $ return [(DEFAULT, [], deflt_rhs)]
 
 --------- Catch-all cases -----------