/// Main resource tracking point.
void ResourcePriorityQueue::scheduledNode(SUnit *SU) {
// Use NULL entry as an event marker to reset
// the DFA state.
if (!SU) {
ResourcesModel->clearResources();
Packet.clear();
return;
}
const SDNode *ScegN = SU->getNode();
// Update reg pressure tracking.
// First update current node.
if (ScegN->isMachineOpcode()) {
// Estimate generated regs.
for (unsigned i = 0, e = ScegN->getNumValues(); i != e; ++i) {
MVT VT = ScegN->getSimpleValueType(i);
if (TLI->isTypeLegal(VT)) {
const TargetRegisterClass *RC = TLI->getRegClassFor(VT);
if (RC)
RegPressure[RC->getID()] += numberRCValSuccInSU(SU, RC->getID());
}
}
// Estimate killed regs.
for (unsigned i = 0, e = ScegN->getNumOperands(); i != e; ++i) {
const SDValue &Op = ScegN->getOperand(i);
MVT VT = Op.getNode()->getSimpleValueType(Op.getResNo());
if (TLI->isTypeLegal(VT)) {
const TargetRegisterClass *RC = TLI->getRegClassFor(VT);
if (RC) {
if (RegPressure[RC->getID()] >
(numberRCValPredInSU(SU, RC->getID())))
RegPressure[RC->getID()] -= numberRCValPredInSU(SU, RC->getID());
else RegPressure[RC->getID()] = 0;
}
}
}
for (SUnit::pred_iterator I = SU->Preds.begin(), E = SU->Preds.end();
I != E; ++I) {
if (I->isCtrl() || (I->getSUnit()->NumRegDefsLeft == 0))
continue;
--I->getSUnit()->NumRegDefsLeft;
}
}
// Reserve resources for this SU.
reserveResources(SU);
// Adjust number of parallel live ranges.
// Heuristic is simple - node with no data successors reduces
// number of live ranges. All others, increase it.
unsigned NumberNonControlDeps = 0;
for (SUnit::const_succ_iterator I = SU->Succs.begin(), E = SU->Succs.end();
I != E; ++I) {
adjustPriorityOfUnscheduledPreds(I->getSUnit());
if (!I->isCtrl())
NumberNonControlDeps++;
}
if (!NumberNonControlDeps) {
if (ParallelLiveRanges >= SU->NumPreds)
ParallelLiveRanges -= SU->NumPreds;
else
ParallelLiveRanges = 0;
}
else
ParallelLiveRanges += SU->NumRegDefsLeft;
// Track parallel live chains.
HorizontalVerticalBalance += (SU->Succs.size() - numberCtrlDepsInSU(SU));
HorizontalVerticalBalance -= (SU->Preds.size() - numberCtrlPredInSU(SU));
}
// ScheduledNode - As nodes are scheduled, we look to see if there are any
// successor nodes that have a single unscheduled predecessor. If so, that
// single predecessor has a higher priority, since scheduling it will make
// the node available.
void LatencyPriorityQueue::ScheduledNode(SUnit *SU) {
for (SUnit::const_succ_iterator I = SU->Succs.begin(), E = SU->Succs.end();
I != E; ++I) {
AdjustPriorityOfUnscheduledPreds(I->getSUnit());
}
}