Fixed a bug in spill cost estimation
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@1500 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/RegAlloc/RegClass.cpp b/lib/CodeGen/RegAlloc/RegClass.cpp
index 3ee79e3..3918871 100644
--- a/lib/CodeGen/RegAlloc/RegClass.cpp
+++ b/lib/CodeGen/RegAlloc/RegClass.cpp
@@ -150,9 +150,9 @@
{
unsigned int IGNodeListSize = IG.getIGNodeList().size();
- long MinSpillCost = -1;
+ double MinSpillCost;
IGNode *MinCostIGNode = NULL;
-
+ bool isFirstNode = true;
// pass over IGNodeList to find the IGNode with minimum spill cost
// among all IGNodes that are not yet pushed on to the stack
@@ -165,11 +165,13 @@
if( ! IGNode->isOnStack() ) {
- long SpillCost = (long) IGNode->getParentLR()->getSpillCost();
+ double SpillCost = (double) IGNode->getParentLR()->getSpillCost() /
+ (double) (IGNode->getCurDegree() + 1);
- if( MinSpillCost == -1) { // for the first IG node
+ if( isFirstNode ) { // for the first IG node
MinSpillCost = SpillCost;
MinCostIGNode = IGNode;
+ isFirstNode = false;
}
else if( MinSpillCost > SpillCost) {