[project @ 2001-09-26 16:19:28 by simonpj]

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

diff --git a/ghc/compiler/simplCore/LiberateCase.lhs b/ghc/compiler/simplCore/LiberateCase.lhs
index e11950c..94a478a 100644 (file)
--- a/ghc/compiler/simplCore/LiberateCase.lhs
+++ b/ghc/compiler/simplCore/LiberateCase.lhs
@@ -8,14 +8,13 @@ module LiberateCase ( liberateCase ) where
 
 #include "HsVersions.h"
 
-import CmdLineOpts     ( DynFlags, DynFlag(..), dopt, opt_LiberateCaseThreshold )
+import CmdLineOpts     ( DynFlags, DynFlag(..), opt_LiberateCaseThreshold )
 import CoreLint                ( showPass, endPass )
 import CoreSyn
 import CoreUnfold      ( couldBeSmallEnoughToInline )
 import Var             ( Id )
 import VarEnv
 import UniqFM          ( ufmToList )
-import Maybes
 import Outputable
 \end{code}
 
@@ -145,12 +144,6 @@ data LibCaseEnv
 initEnv :: Int -> LibCaseEnv
 initEnv bomb_size = LibCaseEnv bomb_size 0 emptyVarEnv emptyVarEnv []
 
-pprEnv :: LibCaseEnv -> SDoc
-pprEnv (LibCaseEnv _ lvl lvl_env _ scruts)
-  = vcat [text "LibCaseEnv" <+> int lvl,
-         fsep (map ppr (ufmToList lvl_env)),
-         fsep (map ppr scruts)]
-
 bombOutSize (LibCaseEnv bomb_size _ _ _ _) = bomb_size
 \end{code}
 
@@ -244,11 +237,8 @@ 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 +296,8 @@ 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}