Also account for the spill code that would be inserted in live-through blocks with interference.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129030 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jakob Stoklund Olesen 2011-04-06 21:32:41 +00:00
parent 1b400e840f
commit 9a54352879

View File

@ -170,7 +170,7 @@ private:
void LRE_DidCloneVirtReg(unsigned, unsigned);
bool addSplitConstraints(unsigned, float&);
float calcGlobalSplitCost(const BitVector&);
float calcGlobalSplitCost(unsigned, const BitVector&);
void splitAroundRegion(LiveInterval&, unsigned, const BitVector&,
SmallVectorImpl<LiveInterval*>&);
void calcGapWeights(unsigned, SmallVectorImpl<float>&);
@ -520,7 +520,8 @@ bool RAGreedy::addSplitConstraints(unsigned PhysReg, float &Cost) {
/// pattern in LiveBundles. This cost should be added to the local cost of the
/// interference pattern in SplitConstraints.
///
float RAGreedy::calcGlobalSplitCost(const BitVector &LiveBundles) {
float RAGreedy::calcGlobalSplitCost(unsigned PhysReg,
const BitVector &LiveBundles) {
float GlobalCost = 0;
ArrayRef<SplitAnalysis::BlockInfo> UseBlocks = SA->getUseBlocks();
for (unsigned i = 0; i != UseBlocks.size(); ++i) {
@ -538,14 +539,24 @@ float RAGreedy::calcGlobalSplitCost(const BitVector &LiveBundles) {
GlobalCost += Ins * SpillPlacer->getBlockFrequency(BC.Number);
}
InterferenceCache::Cursor Intf(IntfCache, PhysReg);
ArrayRef<unsigned> ThroughBlocks = SA->getThroughBlocks();
SplitConstraints.resize(UseBlocks.size() + ThroughBlocks.size());
for (unsigned i = 0; i != ThroughBlocks.size(); ++i) {
unsigned Number = ThroughBlocks[i];
bool RegIn = LiveBundles[Bundles->getBundle(Number, 0)];
bool RegOut = LiveBundles[Bundles->getBundle(Number, 1)];
if (RegIn != RegOut)
GlobalCost += SpillPlacer->getBlockFrequency(Number);
if (!RegIn && !RegOut)
continue;
if (RegIn && RegOut) {
// We need double spill code if this block has interference.
Intf.moveToBlock(Number);
if (Intf.hasInterference())
GlobalCost += 2*SpillPlacer->getBlockFrequency(Number);
continue;
}
// live-in / stack-out or stack-in live-out.
GlobalCost += SpillPlacer->getBlockFrequency(Number);
}
return GlobalCost;
}
@ -811,7 +822,7 @@ unsigned RAGreedy::tryRegionSplit(LiveInterval &VirtReg, AllocationOrder &Order,
continue;
}
Cost += calcGlobalSplitCost(LiveBundles);
Cost += calcGlobalSplitCost(PhysReg, LiveBundles);
DEBUG({
dbgs() << ", total = " << Cost << " with bundles";
for (int i = LiveBundles.find_first(); i>=0; i = LiveBundles.find_next(i))