X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FnativeGen%2FGraphOps.hs;h=308cae0467afe43d0c144f2eb997da61dc6b797c;hb=b7f448a4ebb2b924f279bf49432f07338f41a764;hp=96c8e4e69f2a1509f7ac53e3ae1e4aa96387f44c;hpb=ad94d40948668032189ad22a0ad741ac1f645f50;p=ghc-hetmet.git

diff --git a/compiler/nativeGen/GraphOps.hs b/compiler/nativeGen/GraphOps.hs
index 96c8e4e..308cae0 100644
--- a/compiler/nativeGen/GraphOps.hs
+++ b/compiler/nativeGen/GraphOps.hs
@@ -1,13 +1,6 @@
-
 -- | Basic operations on graphs.
 --
-
-{-# OPTIONS -w #-}
--- The above warning supression flag is a temporary kludge.
--- While working on this module you are encouraged to remove it and fix
--- any warnings in the module. See
---     http://hackage.haskell.org/trac/ghc/wiki/CodingStyle#Warnings
--- for details
+{-# OPTIONS -fno-warn-missing-signatures #-}
 
 module GraphOps (
 	addNode, 	delNode,	getNode,	lookupNode,	modNode,
@@ -35,7 +28,6 @@ import UniqFM
 import Data.List	hiding (union)
 import Data.Maybe
 
-
 -- | Lookup a node from the graph.
 lookupNode 
 	:: Uniquable k
@@ -195,13 +187,13 @@ addConflicts conflicts getClass
 
 	| otherwise
 	= graphMapModify
-	$ (\fm -> foldr	(\u -> addConflictSet1 u getClass conflicts) fm
+	$ (\fm -> foldl' (\g u  -> addConflictSet1 u getClass conflicts g) fm
 		$ uniqSetToList conflicts)
 
 
 addConflictSet1 u getClass set 
- = let	set'	= delOneFromUniqSet set u
-   in	adjustWithDefaultUFM 
+ = case delOneFromUniqSet set u of
+    set' -> adjustWithDefaultUFM
 		(\node -> node 			{ nodeConflicts = unionUniqSets set' (nodeConflicts node) } )
 		(newNode u (getClass u))	{ nodeConflicts = set' }
 		u
@@ -275,10 +267,11 @@ addPreference (u, c) color
 --
 coalesceGraph
 	:: (Uniquable k, Ord k, Eq cls, Outputable k)
-	=>  Graph k cls color
+	=> Triv k cls color
+	-> Graph k cls color
 	-> (Graph k cls color, [(k, k)])
 
-coalesceGraph graph
+coalesceGraph triv graph
  = let
  	-- find all the nodes that have coalescence edges
 	cNodes	= filter (\node -> not $ isEmptyUniqSet (nodeCoalesce node))
@@ -297,7 +290,7 @@ coalesceGraph graph
 	-- do the coalescing, returning the new graph and a list of pairs of keys
 	--	that got coalesced together.
 	(graph', mPairs)
-		= mapAccumL coalesceNodes graph cList
+		= mapAccumL (coalesceNodes False triv) graph cList
 
    in	(graph', catMaybes mPairs)
 
@@ -312,32 +305,33 @@ coalesceGraph graph
 
 coalesceNodes
 	:: (Uniquable k, Ord k, Eq cls, Outputable k)
-	=> Graph k cls color
+	=> Bool			-- ^ If True, coalesce nodes even if this might make the graph
+				--	less colorable (aggressive coalescing)
+	-> Triv  k cls color
+	-> Graph k cls color
 	-> (k, k)		-- ^ keys of the nodes to be coalesced
 	-> (Graph k cls color, Maybe (k, k))
 
-coalesceNodes graph (k1, k2)
+coalesceNodes aggressive triv graph (k1, k2)
 	| (kMin, kMax)	<- if k1 < k2
 				then (k1, k2)
 				else (k2, k1)
 
-	-- nodes must be in the graph
-	, Just nMin	<- lookupNode graph kMin
-	, Just nMax	<- lookupNode graph kMax
+	-- the nodes being coalesced must be in the graph
+	, Just nMin		<- lookupNode graph kMin
+	, Just nMax		<- lookupNode graph kMax
 
-	-- can't coalesce conflicting nodes
+	-- can't coalesce conflicting modes
 	, not $ elementOfUniqSet kMin (nodeConflicts nMax)
 	, not $ elementOfUniqSet kMax (nodeConflicts nMin)
 
-	= coalesceNodes' graph kMin kMax nMin nMax
-
-
+	= coalesceNodes_merge aggressive triv graph kMin kMax nMin nMax
 
-	-- one of the nodes wasn't in the graph anymore
+	-- don't do the coalescing after all
 	| otherwise
 	= (graph, Nothing)
 
-coalesceNodes' graph kMin kMax nMin nMax
+coalesceNodes_merge aggressive triv graph kMin kMax nMin nMax
 
 	-- sanity checks
 	| nodeClass nMin /= nodeClass nMax
@@ -371,9 +365,20 @@ coalesceNodes' graph kMin kMax nMin nMax
 					`delOneFromUniqSet` kMax
 			}
 
-		-- delete the old nodes from the graph and add the new one
-	 	graph'	= addNode kMin node
-	  		$ delNode kMin
+	  in	coalesceNodes_check aggressive triv graph kMin kMax node
+
+coalesceNodes_check aggressive triv graph kMin kMax node
+
+	-- Unless we're coalescing aggressively, if the result node is not trivially
+	--	colorable then don't do the coalescing.
+	| not aggressive
+	, not $ triv (nodeClass node) (nodeConflicts node) (nodeExclusions node)
+	= (graph, Nothing)
+
+	| otherwise
+	= let -- delete the old nodes from the graph and add the new one
+		graph'	= addNode kMin node
+			$ delNode kMin
 			$ delNode kMax
 			$ graph
 
@@ -419,7 +424,7 @@ slurpNodeConflictCount
 
 slurpNodeConflictCount graph
 	= addListToUFM_C
-		(\(c1, n1) (c2, n2) -> (c1, n1 + n2))
+		(\(c1, n1) (_, n2) -> (c1, n1 + n2))
 		emptyUFM
 	$ map 	(\node
 	 	  -> let count	= sizeUniqSet $ nodeConflicts node
@@ -441,6 +446,7 @@ setColor u color
 		u 
 	
 
+{-# INLINE 	adjustWithDefaultUFM #-}
 adjustWithDefaultUFM 
 	:: Uniquable k 
 	=> (a -> a) -> a -> k 
@@ -448,11 +454,11 @@ adjustWithDefaultUFM
 
 adjustWithDefaultUFM f def k map
 	= addToUFM_C 
-		(\old new -> f old)
+		(\old _ -> f old)
 		map
 		k def
 		
-
+{-# INLINE adjustUFM #-}
 adjustUFM 
 	:: Uniquable k
 	=> (a -> a)
@@ -462,5 +468,4 @@ adjustUFM f k map
  = case lookupUFM map k of
  	Nothing	-> map
 	Just a	-> addToUFM map k (f a)
-