X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;ds=sidebyside;f=compiler%2FnativeGen%2FRegAlloc%2FGraph%2FMain.hs;h=5fa771cfb8b97c3332d681c42120c32f43107dc6;hb=703ca1542c8e0983cc9d8eebce6e9f3dd3fd71e2;hp=94b18aeb0a1b7bb0950504b56833001dfb016e7f;hpb=f9288086f935c97812b2d80defcff38baf7b6a6c;p=ghc-hetmet.git

diff --git a/compiler/nativeGen/RegAlloc/Graph/Main.hs b/compiler/nativeGen/RegAlloc/Graph/Main.hs
index 94b18ae..5fa771c 100644
--- a/compiler/nativeGen/RegAlloc/Graph/Main.hs
+++ b/compiler/nativeGen/RegAlloc/Graph/Main.hs
@@ -11,7 +11,6 @@ module RegAlloc.Graph.Main (
 where
 
 import qualified GraphColor	as Color
-import qualified GraphBase	as Color
 import RegAlloc.Liveness
 import RegAlloc.Graph.Spill
 import RegAlloc.Graph.SpillClean
@@ -311,9 +310,16 @@ graphAddCoalesce (r1, r2) graph
 		(vr2, classOfVirtualReg vr2) 
 		graph
 
-	| otherwise
-	= panic "RegAlloc.Graph.Main.graphAddCoalesce: can't coalesce two real regs"
+	-- We can't coalesce two real regs, but there could well be existing
+	--	hreg,hreg moves in the input code. We'll just ignore these
+	--	for coalescing purposes.
+	| RegReal _		<- r1
+	, RegReal _	 	<- r2
+	= graph
 
+graphAddCoalesce _ _
+	= panic "graphAddCoalesce: bogus"
+	
 
 -- | Patch registers in code using the reg -> reg mapping in this graph.
 patchRegsFromGraph