X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FcoreSyn%2FCoreTidy.lhs;h=c928be4ca2157ad1cf8aa6b0248d35a52bf29fee;hb=14a496fd0b3aa821b69eb02736d5f41086576761;hp=11e45b154d9d55db333db473c7c903aecb9293b3;hpb=62eeda5aed31173b234b2965ccf4bd6979ffd9a4;p=ghc-hetmet.git

diff --git a/compiler/coreSyn/CoreTidy.lhs b/compiler/coreSyn/CoreTidy.lhs
index 11e45b1..c928be4 100644
--- a/compiler/coreSyn/CoreTidy.lhs
+++ b/compiler/coreSyn/CoreTidy.lhs
@@ -17,12 +17,11 @@ import CoreSyn
 import CoreArity
 import Id
 import IdInfo
-import Type
+import TcType( tidyType, tidyTyVarBndr )
 import Var
 import VarEnv
 import UniqFM
 import Name hiding (tidyNameOcc)
-import OccName
 import SrcLoc
 import Maybes
 
@@ -124,7 +123,7 @@ tidyVarOcc (_, var_env) v = lookupVarEnv var_env v `orElse` v
 -- tidyBndr is used for lambda and case binders
 tidyBndr :: TidyEnv -> Var -> (TidyEnv, Var)
 tidyBndr env var
-  | isTyVar var = tidyTyVarBndr env var
+  | isTyCoVar var = tidyTyVarBndr env var
   | otherwise   = tidyIdBndr env var
 
 tidyBndrs :: TidyEnv -> [Var] -> (TidyEnv, [Var])
@@ -154,10 +153,10 @@ tidyLetBndr env (id,rhs)
 	-- separate compilation boundaries
     final_id = new_id `setIdInfo` new_info
     idinfo   = idInfo id
-    new_info = vanillaIdInfo
+    new_info = idInfo new_id
 		`setArityInfo`		exprArity rhs
-		`setAllStrictnessInfo`	newStrictnessInfo idinfo
-		`setNewDemandInfo`	newDemandInfo idinfo
+		`setStrictnessInfo`	strictnessInfo idinfo
+		`setDemandInfo`	demandInfo idinfo
 		`setInlinePragInfo`	inlinePragInfo idinfo
 
     -- Override the env we get back from tidyId with the new IdInfo
@@ -167,7 +166,7 @@ tidyLetBndr env (id,rhs)
 -- Non-top-level variables
 tidyIdBndr :: TidyEnv -> Id -> (TidyEnv, Id)
 tidyIdBndr env@(tidy_env, var_env) id
-  = -- do this pattern match strictly, otherwise we end up holding on to
+  = -- Do this pattern match strictly, otherwise we end up holding on to
     -- stuff in the OccName.
     case tidyOccName tidy_env (getOccName id) of { (tidy_env', occ') -> 
     let 
@@ -175,24 +174,36 @@ tidyIdBndr env@(tidy_env, var_env) id
 	-- The SrcLoc isn't important now, 
 	-- though we could extract it from the Id
 	-- 
-	-- All nested Ids now have the same IdInfo, namely vanillaIdInfo,
-	-- which should save some space; except that we hang onto dead-ness
-	-- (at the moment, solely to make printing tidy core nicer)
-	-- But note that tidyLetBndr puts some of it back.
         ty'      = tidyType env (idType id)
         name'    = mkInternalName (idUnique id) occ' noSrcSpan
 	id'      = mkLocalIdWithInfo name' ty' new_info
 	var_env' = extendVarEnv var_env id id'
-        new_info | isDeadOcc (idOccInfo id) = deadIdInfo
-	         | otherwise 	            = vanillaIdInfo
+
+	-- Note [Tidy IdInfo]
+        new_info = vanillaIdInfo `setOccInfo` occInfo old_info
+	old_info = idInfo id
     in
-     ((tidy_env', var_env'), id')
+    ((tidy_env', var_env'), id')
    }
-
-deadIdInfo :: IdInfo
-deadIdInfo = vanillaIdInfo `setOccInfo` IAmDead
 \end{code}
 
+Note [Tidy IdInfo]
+~~~~~~~~~~~~~~~~~~
+All nested Ids now have the same IdInfo, namely vanillaIdInfo, which
+should save some space; except that we preserve occurrence info for
+two reasons:
+
+  (a) To make printing tidy core nicer
+
+  (b) Because we tidy RULES and InlineRules, which may then propagate
+      via --make into the compilation of the next module, and we want
+      the benefit of that occurrence analysis when we use the rule or
+      or inline the function.  In particular, it's vital not to lose
+      loop-breaker info, else we get an infinite inlining loop
+      
+Note that tidyLetBndr puts more IdInfo back.
+
+
 \begin{code}
 (=:) :: a -> (a -> b) -> b
 m =: k = m `seq` k m