X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fmain%2FDynFlags.hs;h=2d28ae6552c97234b169d5497db6c3fccebdf94b;hb=e923340fea0fea85f55600b8ee709f1cf8b62803;hp=9a7de07c5ec0778a351aef5c9c62c54965eb8e42;hpb=ae019a20d2db44c52767f5cd6291f3276067446b;p=ghc-hetmet.git

diff --git a/compiler/main/DynFlags.hs b/compiler/main/DynFlags.hs
index 9a7de07..2d28ae6 100644
--- a/compiler/main/DynFlags.hs
+++ b/compiler/main/DynFlags.hs
@@ -722,19 +722,27 @@ getCoreToDo dflags
 -- Case-liberation for -O2.  This should be after
 -- strictness analysis and the simplification which follows it.
 
-	case rule_check of { Just pat -> CoreDoRuleCheck 0 pat; Nothing -> CoreDoNothing },
+	case rule_check of { Just pat -> CoreDoRuleCheck 0 pat; Nothing -> CoreDoNothing }
+     ]
+
+	++ 
 
-	if opt_level >= 2 then
-	   CoreLiberateCase
-	else
-	   CoreDoNothing,
-	if opt_level >= 2 then
-	   CoreDoSpecConstr
-	else
-	   CoreDoNothing,
+     if opt_level >= 2 then
+	   [  CoreLiberateCase,
+	      CoreDoSimplify (SimplPhase 0) [
+		  MaxSimplifierIterations max_iter
+	      ],	-- Run the simplifier after LiberateCase to vastly 
+			-- reduce the possiblility of shadowing
+			-- Reason: see Note [Shadowing] in SpecConstr.lhs
+	     CoreDoSpecConstr
+	   ]
+     else
+	   []
+
+	++
 
 	-- Final clean-up simplification:
-	CoreDoSimplify (SimplPhase 0) [
+     [	CoreDoSimplify (SimplPhase 0) [
 	  MaxSimplifierIterations max_iter
 	]
      ]