Committed for compliation. Not yet final.
--Ruchira
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@505 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/RegAlloc/InterferenceGraph.h b/lib/CodeGen/RegAlloc/InterferenceGraph.h
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+++ b/lib/CodeGen/RegAlloc/InterferenceGraph.h
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+/* Title: InterferenceGraph.h
+ Author: Ruchira Sasanka
+ Date: July 20, 01
+ Purpose: Interference Graph used for register coloring.
+
+ Notes:
+ Adj Info is stored in the lower trangular matrix (i.e., row > col )
+
+ This class must be used in the following way:
+
+ * Construct class
+ * call addLRToIG as many times to add ALL LRs to this IG
+ * call createGraph to create the actual matrix
+ * Then setInterference, getInterference, mergeIGNodesOfLRs can be
+ called as desired to modify the graph.
+ * Once the modifications to the graph are over, call
+ setCurDegreeOfIGNodes() before pushing IGNodes on to stack for coloring.
+*/
+
+
+#ifndef INTERFERENCE_GRAPH_H
+#define INTERFERENCE_GRAPH_H
+
+
+#include "llvm/CodeGen/IGNode.h"
+
+typedef vector <IGNode *> IGNodeListType;
+
+
+class InterferenceGraph
+{
+ char **IG; // a poiner to the interference graph
+ unsigned int Size; // size of a side of the IG
+ RegClass *const RegCl; // RegCl contains this IG
+ IGNodeListType IGNodeList; // a list of all IGNodes in a reg class
+
+ // for asserting this IG node is infact in the IGNodeList of this class
+ inline void assertIGNode(const IGNode *const Node) const {
+ assert( IGNodeList[ Node->getIndex() ] == Node );
+ }
+
+
+
+ public:
+
+ // the matrix is not yet created by the constructor. Call createGraph()
+ // to create it after adding all IGNodes to the IGNodeList
+
+ InterferenceGraph(RegClass *const RC);
+ void createGraph();
+
+ void addLRToIG(LiveRange *const LR);
+
+ void setInterference(const LiveRange *const LR1,
+ const LiveRange *const LR2 );
+
+ unsigned getInterference(const LiveRange *const LR1,
+ const LiveRange *const LR2 ) const ;
+
+ void mergeIGNodesOfLRs(const LiveRange *const LR1, LiveRange *const LR2);
+
+ inline IGNodeListType &getIGNodeList() { return IGNodeList; }
+
+ void setCurDegreeOfIGNodes();
+
+ void printIG() const;
+ void printIGNodeList() const;
+
+ ~InterferenceGraph();
+
+
+};
+
+
+#endif
+