Try and rewrite reloads to reg-reg moves in the spill cleaner

[ghc-hetmet.git] / compiler / nativeGen / GraphColor.hs

diff --git a/compiler/nativeGen/GraphColor.hs b/compiler/nativeGen/GraphColor.hs
index 6956c8d..307803a 100644 (file)
--- 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