Added destructors and comments.
Added correct spill candidate selection logic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@1493 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/RegAlloc/InterferenceGraph.cpp b/lib/CodeGen/RegAlloc/InterferenceGraph.cpp
index d8ec247..e18c9a7 100644
--- a/lib/CodeGen/RegAlloc/InterferenceGraph.cpp
+++ b/lib/CodeGen/RegAlloc/InterferenceGraph.cpp
@@ -1,6 +1,10 @@
#include "llvm/CodeGen/InterferenceGraph.h"
-
+//-----------------------------------------------------------------------------
+// Constructor: Records the RegClass and initalizes IGNodeList.
+// The matrix is NOT yet created by the constructor. Call createGraph()
+// to create it after adding all IGNodes to the IGNodeList.
+//-----------------------------------------------------------------------------
InterferenceGraph::InterferenceGraph(RegClass *const RC) : RegCl(RC),
IGNodeList()
{
@@ -11,14 +15,34 @@
}
}
-InterferenceGraph:: ~InterferenceGraph() { // destructor
- if( IG )
- delete []IG;
+
+//-----------------------------------------------------------------------------
+// destructor. Deletes the bit matrix and all IGNodes
+//-----------------------------------------------------------------------------
+InterferenceGraph:: ~InterferenceGraph() {
+
+ // delete the matrix
+ //
+ if( IG )
+ delete []IG;
+
+ // delete all IGNodes in the IGNodeList
+ //
+ vector<IGNode *>::const_iterator IGIt = IGNodeList.begin();
+ for(unsigned i=0; i < IGNodeList.size() ; ++i) {
+
+ const IGNode *const Node = IGNodeList[i];
+ if( Node ) delete Node;
}
+}
+//-----------------------------------------------------------------------------
+// Creates (dynamically allocates) the bit matrix necessary to hold the
+// interference graph.
+//-----------------------------------------------------------------------------
void InterferenceGraph::createGraph()
{
Size = IGNodeList.size();
@@ -32,21 +56,24 @@
IG[i][j] = 0;
}
-
-
+//-----------------------------------------------------------------------------
+// creates a new IGNode for the given live range and add to IG
+//-----------------------------------------------------------------------------
void InterferenceGraph::addLRToIG(LiveRange *const LR)
{
IGNode *Node = new IGNode(LR, IGNodeList.size() );
IGNodeList.push_back( Node );
- //Node->setRegClass( RegCl );
+
}
+//-----------------------------------------------------------------------------
+// set interference for two live ranges
// update both the matrix and AdjLists of nodes.
// If there is already an interference between LR1 and LR2, adj lists
// are not updated. LR1 and LR2 must be distinct since if not, it suggests
// that there is some wrong logic in some other method.
-
+//-----------------------------------------------------------------------------
void InterferenceGraph::setInterference(const LiveRange *const LR1,
const LiveRange *const LR2 ) {
assert(LR1 != LR2);
@@ -79,7 +106,9 @@
}
-
+//----------------------------------------------------------------------------
+// return whether two live ranges interfere
+//----------------------------------------------------------------------------
unsigned InterferenceGraph::getInterference(const LiveRange *const LR1,
const LiveRange *const LR2 ) const {
@@ -100,11 +129,12 @@
}
-
+//----------------------------------------------------------------------------
// Merge 2 IGNodes. The neighbors of the SrcNode will be added to the DestNode.
// Then the IGNode2L will be deleted. Necessary for coalescing.
// IMPORTANT: The live ranges are NOT merged by this method. Use
// LiveRangeInfo::unionAndUpdateLRs for that purpose.
+//----------------------------------------------------------------------------
void InterferenceGraph::mergeIGNodesOfLRs(const LiveRange *const LR1,
LiveRange *const LR2 ) {
@@ -147,11 +177,6 @@
setInterference(LR1, LROfNeigh );
}
- //cout<< " #Neighs - Neigh: ["<< NeighNode->getIndex()<< "] ";
- //cout << NeighNode->getNumOfNeighbors();
- //cout << " Dest: [" << DestNode->getIndex() << "] ";
- //cout << DestNode->getNumOfNeighbors() << endl;
-
}
IGNodeList[ SrcInd ] = NULL;
@@ -162,10 +187,10 @@
}
-
+//----------------------------------------------------------------------------
// must be called after modifications to the graph are over but before
// pushing IGNodes on to the stack for coloring.
-
+//----------------------------------------------------------------------------
void InterferenceGraph::setCurDegreeOfIGNodes()
{
unsigned Size = IGNodeList.size();
@@ -183,7 +208,9 @@
//--------------------- debugging (Printing) methods -----------------------
-
+//----------------------------------------------------------------------------
+// Print the IGnodes
+//----------------------------------------------------------------------------
void InterferenceGraph::printIG() const
{
@@ -203,7 +230,9 @@
}
}
-
+//----------------------------------------------------------------------------
+// Print the IGnodes in the IGNode List
+//----------------------------------------------------------------------------
void InterferenceGraph::printIGNodeList() const
{
vector<IGNode *>::const_iterator IGIt = IGNodeList.begin(); // hash map iter