+{-# OPTIONS -fno-warn-missing-signatures #-}
-- | Basic operations on graphs.
--
--- TODO: refine coalescing crieteria
-
-{-# OPTIONS -fno-warn-missing-signatures #-}
module GraphOps (
addNode, delNode, getNode, lookupNode, modNode,
union,
addConflict, delConflict, addConflicts,
addCoalesce, delCoalesce,
- addExclusion,
+ addExclusion, addExclusions,
addPreference,
coalesceNodes, coalesceGraph,
freezeNode, freezeOneInGraph, freezeAllInGraph,
(newNode u (getClass u)) { nodeExclusions = unitUniqSet color }
u
+addExclusions
+ :: (Uniquable k, Uniquable color)
+ => k -> (k -> cls) -> [color]
+ -> Graph k cls color -> Graph k cls color
+
+addExclusions u getClass colors graph
+ = foldr (addExclusion u getClass) graph colors
+
-- | Add a coalescence edge to the graph, creating nodes if requried.
-- It is considered adventageous to assign the same color to nodes in a coalesence.
-- less colorable (aggressive coalescing)
-> Triv k cls color
-> Graph k cls color
- -> (Graph k cls color, [(k, k)])
+ -> ( Graph k cls color
+ , [(k, k)]) -- pairs of nodes that were coalesced, in the order that the
+ -- coalescing was applied.
coalesceGraph aggressive triv graph
= coalesceGraph' aggressive triv graph []
-- keep running until there are no more coalesces can be found
in case catMaybes mPairs of
- [] -> (graph', kkPairsAcc)
- pairs -> coalesceGraph' aggressive triv graph' (pairs ++ kkPairsAcc)
+ [] -> (graph', reverse kkPairsAcc)
+ pairs -> coalesceGraph' aggressive triv graph' (reverse pairs ++ kkPairsAcc)
--- | Coalesce this pair of nodes unconditionally / agressively.
+-- | Coalesce this pair of nodes unconditionally \/ agressively.
-- The resulting node is the one with the least key.
--
-- returns: Just the pair of keys if the nodes were coalesced
, not $ elementOfUniqSet kMin (nodeConflicts nMax)
, not $ elementOfUniqSet kMax (nodeConflicts nMin)
+ -- can't coalesce the same node
+ , nodeId nMin /= nodeId nMax
+
= coalesceNodes_merge aggressive triv graph kMin kMax nMin nMax
-- don't do the coalescing after all
| not (isNothing (nodeColor nMin) && isNothing (nodeColor nMax))
= error "GraphOps.coalesceNodes: can't coalesce colored nodes."
- | nodeId nMin == nodeId nMax
- = error "GraphOps.coalesceNodes: can't coalesce the same node."
-
---
| otherwise
= let
freezeNode k
= graphMapModify
$ \fm ->
- let
- -- freeze all the edges in the node to be frozen
+ let -- freeze all the edges in the node to be frozen
Just node = lookupUFM fm k
node' = node
{ nodeCoalesce = emptyUniqSet }
-- update back edges pointing to this node
freezeEdge k node
= if elementOfUniqSet k (nodeCoalesce node)
- then node
- { nodeCoalesce = delOneFromUniqSet (nodeCoalesce node) k }
- else panic "GraphOps.freezeNode: edge to freeze wasn't in the coalesce set"
+ then node { nodeCoalesce = delOneFromUniqSet (nodeCoalesce node) k }
+ else node -- panic "GraphOps.freezeNode: edge to freeze wasn't in the coalesce set"
+ -- If the edge isn't actually in the coelesce set then just ignore it.
fm2 = foldUniqSet (adjustUFM (freezeEdge k)) fm1
$ nodeCoalesce node
-- classes.. this is just a heuristic, after all.
--
-- IDEA: freezing a node might free it up for Simplify.. would be good to check for triv
--- right here, and add it to a worklist if known triv/non-move nodes.
+-- right here, and add it to a worklist if known triv\/non-move nodes.
--
freezeOneInGraph
:: (Uniquable k, Outputable k)