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authorSylvain Henry <sylvain@haskus.fr>2020-04-20 16:54:38 +0200
committerMarge Bot <ben+marge-bot@smart-cactus.org>2020-04-26 13:55:14 -0400
commitaf332442123878c1b61d236dce46418efcbe8750 (patch)
treeec4b332843cdd4fedb4aa60b11b7b8dba82a0764 /compiler/utils/GraphBase.hs
parentb0fbfc7582fb81314dc28a056536737fb5eeaa6e (diff)
downloadhaskell-af332442123878c1b61d236dce46418efcbe8750.tar.gz
Modules: Utils and Data (#13009)
Update Haddock submodule Metric Increase: haddock.compiler
Diffstat (limited to 'compiler/utils/GraphBase.hs')
-rw-r--r--compiler/utils/GraphBase.hs107
1 files changed, 0 insertions, 107 deletions
diff --git a/compiler/utils/GraphBase.hs b/compiler/utils/GraphBase.hs
deleted file mode 100644
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--- a/compiler/utils/GraphBase.hs
+++ /dev/null
@@ -1,107 +0,0 @@
-
--- | Types for the general graph colorer.
-module GraphBase (
- Triv,
- Graph (..),
- initGraph,
- graphMapModify,
-
- Node (..), newNode,
-)
-
-
-where
-
-import GhcPrelude
-
-import GHC.Types.Unique.Set
-import GHC.Types.Unique.FM
-
-
--- | A fn to check if a node is trivially colorable
--- For graphs who's color classes are disjoint then a node is 'trivially colorable'
--- when it has less neighbors and exclusions than available colors for that node.
---
--- For graph's who's color classes overlap, ie some colors alias other colors, then
--- this can be a bit more tricky. There is a general way to calculate this, but
--- it's likely be too slow for use in the code. The coloring algorithm takes
--- a canned function which can be optimised by the user to be specific to the
--- specific graph being colored.
---
--- for details, see "A Generalised Algorithm for Graph-Coloring Register Allocation"
--- Smith, Ramsey, Holloway - PLDI 2004.
---
-type Triv k cls color
- = cls -- the class of the node we're trying to color.
- -> UniqSet k -- the node's neighbors.
- -> UniqSet color -- the node's exclusions.
- -> Bool
-
-
--- | The Interference graph.
--- There used to be more fields, but they were turfed out in a previous revision.
--- maybe we'll want more later..
---
-data Graph k cls color
- = Graph {
- -- | All active nodes in the graph.
- graphMap :: UniqFM (Node k cls color) }
-
-
--- | An empty graph.
-initGraph :: Graph k cls color
-initGraph
- = Graph
- { graphMap = emptyUFM }
-
-
--- | Modify the finite map holding the nodes in the graph.
-graphMapModify
- :: (UniqFM (Node k cls color) -> UniqFM (Node k cls color))
- -> Graph k cls color -> Graph k cls color
-
-graphMapModify f graph
- = graph { graphMap = f (graphMap graph) }
-
-
-
--- | Graph nodes.
--- Represents a thing that can conflict with another thing.
--- For the register allocater the nodes represent registers.
---
-data Node k cls color
- = Node {
- -- | A unique identifier for this node.
- nodeId :: k
-
- -- | The class of this node,
- -- determines the set of colors that can be used.
- , nodeClass :: cls
-
- -- | The color of this node, if any.
- , nodeColor :: Maybe color
-
- -- | Neighbors which must be colored differently to this node.
- , nodeConflicts :: UniqSet k
-
- -- | Colors that cannot be used by this node.
- , nodeExclusions :: UniqSet color
-
- -- | Colors that this node would prefer to be, in descending order.
- , nodePreference :: [color]
-
- -- | Neighbors that this node would like to be colored the same as.
- , nodeCoalesce :: UniqSet k }
-
-
--- | An empty node.
-newNode :: k -> cls -> Node k cls color
-newNode k cls
- = Node
- { nodeId = k
- , nodeClass = cls
- , nodeColor = Nothing
- , nodeConflicts = emptyUniqSet
- , nodeExclusions = emptyUniqSet
- , nodePreference = []
- , nodeCoalesce = emptyUniqSet }