[project @ 2000-12-08 13:44:28 by simonpj]

LiberateCase fiddling

diff --git a/ghc/compiler/simplCore/LiberateCase.lhs b/ghc/compiler/simplCore/LiberateCase.lhs
index e11950c..d9ba473 100644 (file)
--- a/ghc/compiler/simplCore/LiberateCase.lhs
+++ b/ghc/compiler/simplCore/LiberateCase.lhs
@@ -244,11 +244,8 @@ Ids
 libCaseId :: LibCaseEnv -> Id -> CoreExpr
 libCaseId env v
   | Just the_bind <- lookupRecId env v -- It's a use of a recursive thing
-  -- = not (null free_scruts)          -- with free vars scrutinised in RHS
-  = if null free_scruts then
-       pprTrace "No:" (ppr v $$ pprEnv env) (Var v)
-    else
-       pprTrace "Yes:" (ppr v) $ Let the_bind (Var v)
+  , not (null free_scruts)             -- with free vars scrutinised in RHS
+  = Let the_bind (Var v)
 
   | otherwise
   = Var v
@@ -306,8 +303,8 @@ lookupLevel (LibCaseEnv bomb lvl lvl_env rec_env scruts) id
 
 freeScruts :: LibCaseEnv
           -> LibCaseLevel      -- Level of the recursive Id
-          -> [Id]              -- Ids that are bound ouside the recursive Id, (level <=)
-                               -- but which are scrutinised on the way to this call
+          -> [Id]              -- Ids that are scrutinised between the binding
+                               -- of the recursive Id and here
 freeScruts (LibCaseEnv bomb lvl lvl_env rec_env scruts) rec_bind_lvl
-  = [v | (v,lvl) <- scruts, lvl <= rec_bind_lvl]
+  = [v | (v,scrut_lvl) <- scruts, scrut_lvl > rec_bind_lvl]
 \end{code}