[project @ 2004-08-17 15:23:47 by simonpj]

[ghc-hetmet.git] / ghc / compiler / utils / Digraph.lhs

diff --git a/ghc/compiler/utils/Digraph.lhs b/ghc/compiler/utils/Digraph.lhs
index cd0e17d..0eff6da 100644 (file)
--- a/ghc/compiler/utils/Digraph.lhs
+++ b/ghc/compiler/utils/Digraph.lhs
@@ -32,7 +32,7 @@ module Digraph(
 ------------------------------------------------------------------------------
 
 
-import Util    ( sortLt )
+import Util    ( sortLe )
 
 -- Extensions
 import MONAD_ST
@@ -100,8 +100,8 @@ stronglyConnCompR [] = []  -- added to avoid creating empty array in graphFromEd
 stronglyConnCompR edges
   = map decode forest
   where
-    (graph, vertex_fn) = graphFromEdges edges
-    forest            = scc graph
+    (graph, vertex_fn) = _scc_ "graphFromEdges" graphFromEdges edges
+    forest            = _scc_ "Digraph.scc" scc graph
     decode (Node v []) | mentions_itself v = CyclicSCC [vertex_fn v]
                       | otherwise         = AcyclicSCC (vertex_fn v)
     decode other = CyclicSCC (dec other [])
@@ -163,14 +163,16 @@ graphFromEdges edges
   where
     max_v                  = length edges - 1
     bounds          = (0,max_v) :: (Vertex, Vertex)
-    sorted_edges    = sortLt lt edges
+    sorted_edges    = let
+                        (_,k1,_) `le` (_,k2,_) = case k1 `compare` k2 of { GT -> False; other -> True }
+                     in
+                       sortLe le edges
     edges1         = zipWith (,) [0..] sorted_edges
 
     graph          = array bounds [(,) v (mapMaybe key_vertex ks) | (,) v (_,    _, ks) <- edges1]
     key_map        = array bounds [(,) v k                        | (,) v (_,    k, _ ) <- edges1]
     vertex_map     = array bounds edges1
 
-    (_,k1,_) `lt` (_,k2,_) = case k1 `compare` k2 of { LT -> True; other -> False }
 
     -- key_vertex :: key -> Maybe Vertex
     --         returns Nothing for non-interesting vertices