X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FnativeGen%2FGraphColor.hs;h=307803a988109660ca35c224bb2f1b1c7e4436c5;hb=86f1f4e0748ba1146cf74786af38a68a88164e2f;hp=6956c8d5b58565ed9f2da766f932269f94a228c6;hpb=12d0b38821771fd9820d655ed73b29c688cb7b59;p=ghc-hetmet.git

diff --git a/compiler/nativeGen/GraphColor.hs b/compiler/nativeGen/GraphColor.hs
index 6956c8d..307803a 100644
--- a/compiler/nativeGen/GraphColor.hs
+++ b/compiler/nativeGen/GraphColor.hs
@@ -67,8 +67,12 @@ colorGraph iterative colors triv spill graph0
  	-- If iterative coalescing is enabled, the scanner will coalesce the graph as does its business.
 	--	We need to apply all the coalescences found by the scanner to the original
 	--	graph before doing assignColors.
+	--
+	--	Because we've got the whole, non-pruned graph here we turn on aggressive coalecing
+	--	to force all the (conservative) coalescences found during scanning.
+	--
 	(graph_scan_coalesced, _)
-		= mapAccumL (coalesceNodes False triv) graph_coalesced kksCoalesce2
+		= mapAccumL (coalesceNodes True triv) graph_coalesced kksCoalesce2
  
 	-- color the trivially colorable nodes
 	--	during scanning, keys of triv nodes were added to the front of the list as they were found
@@ -150,7 +154,10 @@ colorScan_spin iterative triv spill graph
 			$ graph
 
 	, ksTrivFound	<- map nodeId nsTrivFound
-	, graph3	<- foldr delNode graph ksTrivFound
+	, graph3	<- foldr (\k g -> let Just g' = delNode k g
+	   				  in  g')
+				graph ksTrivFound
+
 	= colorScan_spin iterative triv spill graph3
 		(ksTrivFound ++ ksTriv)
 		ksSpill
@@ -200,8 +207,8 @@ colorScan_spin iterative triv spill graph
 colorScan_spill iterative triv spill graph
 	ksTriv ksSpill kksCoalesce
 
- = let	kSpill	= spill graph
- 	graph'	= delNode kSpill graph
+ = let	kSpill		= spill graph
+ 	Just graph'	= delNode kSpill graph
    in	colorScan_spin iterative triv spill graph'
    		ksTriv (kSpill : ksSpill) kksCoalesce