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-rw-r--r--lib/Target/AMDGPU/GCNSchedStrategy.cpp122
1 files changed, 57 insertions, 65 deletions
diff --git a/lib/Target/AMDGPU/GCNSchedStrategy.cpp b/lib/Target/AMDGPU/GCNSchedStrategy.cpp
index d414b899050a..f09b7f6cff22 100644
--- a/lib/Target/AMDGPU/GCNSchedStrategy.cpp
+++ b/lib/Target/AMDGPU/GCNSchedStrategy.cpp
@@ -28,18 +28,6 @@ GCNMaxOccupancySchedStrategy::GCNMaxOccupancySchedStrategy(
const MachineSchedContext *C) :
GenericScheduler(C), TargetOccupancy(0), MF(nullptr) { }
-static unsigned getMaxWaves(unsigned SGPRs, unsigned VGPRs,
- const MachineFunction &MF) {
-
- const SISubtarget &ST = MF.getSubtarget<SISubtarget>();
- const SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
- unsigned MinRegOccupancy = std::min(ST.getOccupancyWithNumSGPRs(SGPRs),
- ST.getOccupancyWithNumVGPRs(VGPRs));
- return std::min(MinRegOccupancy,
- ST.getOccupancyWithLocalMemSize(MFI->getLDSSize(),
- MF.getFunction()));
-}
-
void GCNMaxOccupancySchedStrategy::initialize(ScheduleDAGMI *DAG) {
GenericScheduler::initialize(DAG);
@@ -47,7 +35,7 @@ void GCNMaxOccupancySchedStrategy::initialize(ScheduleDAGMI *DAG) {
MF = &DAG->MF;
- const SISubtarget &ST = MF->getSubtarget<SISubtarget>();
+ const GCNSubtarget &ST = MF->getSubtarget<GCNSubtarget>();
// FIXME: This is also necessary, because some passes that run after
// scheduling and before regalloc increase register pressure.
@@ -81,7 +69,7 @@ void GCNMaxOccupancySchedStrategy::initCandidate(SchedCandidate &Cand, SUnit *SU
Cand.AtTop = AtTop;
// getDownwardPressure() and getUpwardPressure() make temporary changes to
- // the the tracker, so we need to pass those function a non-const copy.
+ // the tracker, so we need to pass those function a non-const copy.
RegPressureTracker &TempTracker = const_cast<RegPressureTracker&>(RPTracker);
std::vector<unsigned> Pressure;
@@ -200,34 +188,30 @@ SUnit *GCNMaxOccupancySchedStrategy::pickNodeBidirectional(bool &IsTopNode) {
setPolicy(TopPolicy, /*IsPostRA=*/false, Top, &Bot);
// See if BotCand is still valid (because we previously scheduled from Top).
- DEBUG(dbgs() << "Picking from Bot:\n");
+ LLVM_DEBUG(dbgs() << "Picking from Bot:\n");
if (!BotCand.isValid() || BotCand.SU->isScheduled ||
BotCand.Policy != BotPolicy) {
BotCand.reset(CandPolicy());
pickNodeFromQueue(Bot, BotPolicy, DAG->getBotRPTracker(), BotCand);
assert(BotCand.Reason != NoCand && "failed to find the first candidate");
} else {
- DEBUG(traceCandidate(BotCand));
+ LLVM_DEBUG(traceCandidate(BotCand));
}
// Check if the top Q has a better candidate.
- DEBUG(dbgs() << "Picking from Top:\n");
+ LLVM_DEBUG(dbgs() << "Picking from Top:\n");
if (!TopCand.isValid() || TopCand.SU->isScheduled ||
TopCand.Policy != TopPolicy) {
TopCand.reset(CandPolicy());
pickNodeFromQueue(Top, TopPolicy, DAG->getTopRPTracker(), TopCand);
assert(TopCand.Reason != NoCand && "failed to find the first candidate");
} else {
- DEBUG(traceCandidate(TopCand));
+ LLVM_DEBUG(traceCandidate(TopCand));
}
// Pick best from BotCand and TopCand.
- DEBUG(
- dbgs() << "Top Cand: ";
- traceCandidate(TopCand);
- dbgs() << "Bot Cand: ";
- traceCandidate(BotCand);
- );
+ LLVM_DEBUG(dbgs() << "Top Cand: "; traceCandidate(TopCand);
+ dbgs() << "Bot Cand: "; traceCandidate(BotCand););
SchedCandidate Cand;
if (TopCand.Reason == BotCand.Reason) {
Cand = BotCand;
@@ -256,10 +240,7 @@ SUnit *GCNMaxOccupancySchedStrategy::pickNodeBidirectional(bool &IsTopNode) {
}
}
}
- DEBUG(
- dbgs() << "Picking: ";
- traceCandidate(Cand);
- );
+ LLVM_DEBUG(dbgs() << "Picking: "; traceCandidate(Cand););
IsTopNode = Cand.AtTop;
return Cand.SU;
@@ -305,20 +286,20 @@ SUnit *GCNMaxOccupancySchedStrategy::pickNode(bool &IsTopNode) {
if (SU->isBottomReady())
Bot.removeReady(SU);
- DEBUG(dbgs() << "Scheduling SU(" << SU->NodeNum << ") " << *SU->getInstr());
+ LLVM_DEBUG(dbgs() << "Scheduling SU(" << SU->NodeNum << ") "
+ << *SU->getInstr());
return SU;
}
GCNScheduleDAGMILive::GCNScheduleDAGMILive(MachineSchedContext *C,
std::unique_ptr<MachineSchedStrategy> S) :
ScheduleDAGMILive(C, std::move(S)),
- ST(MF.getSubtarget<SISubtarget>()),
+ ST(MF.getSubtarget<GCNSubtarget>()),
MFI(*MF.getInfo<SIMachineFunctionInfo>()),
- StartingOccupancy(ST.getOccupancyWithLocalMemSize(MFI.getLDSSize(),
- MF.getFunction())),
+ StartingOccupancy(MFI.getOccupancy()),
MinOccupancy(StartingOccupancy), Stage(0), RegionIdx(0) {
- DEBUG(dbgs() << "Starting occupancy is " << StartingOccupancy << ".\n");
+ LLVM_DEBUG(dbgs() << "Starting occupancy is " << StartingOccupancy << ".\n");
}
void GCNScheduleDAGMILive::schedule() {
@@ -338,12 +319,12 @@ void GCNScheduleDAGMILive::schedule() {
if (LIS) {
PressureBefore = Pressure[RegionIdx];
- DEBUG(dbgs() << "Pressure before scheduling:\nRegion live-ins:";
- GCNRPTracker::printLiveRegs(dbgs(), LiveIns[RegionIdx], MRI);
- dbgs() << "Region live-in pressure: ";
- llvm::getRegPressure(MRI, LiveIns[RegionIdx]).print(dbgs());
- dbgs() << "Region register pressure: ";
- PressureBefore.print(dbgs()));
+ LLVM_DEBUG(dbgs() << "Pressure before scheduling:\nRegion live-ins:";
+ GCNRPTracker::printLiveRegs(dbgs(), LiveIns[RegionIdx], MRI);
+ dbgs() << "Region live-in pressure: ";
+ llvm::getRegPressure(MRI, LiveIns[RegionIdx]).print(dbgs());
+ dbgs() << "Region register pressure: ";
+ PressureBefore.print(dbgs()));
}
ScheduleDAGMILive::schedule();
@@ -356,45 +337,54 @@ void GCNScheduleDAGMILive::schedule() {
GCNMaxOccupancySchedStrategy &S = (GCNMaxOccupancySchedStrategy&)*SchedImpl;
auto PressureAfter = getRealRegPressure();
- DEBUG(dbgs() << "Pressure after scheduling: "; PressureAfter.print(dbgs()));
+ LLVM_DEBUG(dbgs() << "Pressure after scheduling: ";
+ PressureAfter.print(dbgs()));
if (PressureAfter.getSGPRNum() <= S.SGPRCriticalLimit &&
PressureAfter.getVGPRNum() <= S.VGPRCriticalLimit) {
Pressure[RegionIdx] = PressureAfter;
- DEBUG(dbgs() << "Pressure in desired limits, done.\n");
+ LLVM_DEBUG(dbgs() << "Pressure in desired limits, done.\n");
return;
}
- unsigned WavesAfter = getMaxWaves(PressureAfter.getSGPRNum(),
- PressureAfter.getVGPRNum(), MF);
- unsigned WavesBefore = getMaxWaves(PressureBefore.getSGPRNum(),
- PressureBefore.getVGPRNum(), MF);
- DEBUG(dbgs() << "Occupancy before scheduling: " << WavesBefore <<
- ", after " << WavesAfter << ".\n");
+ unsigned Occ = MFI.getOccupancy();
+ unsigned WavesAfter = std::min(Occ, PressureAfter.getOccupancy(ST));
+ unsigned WavesBefore = std::min(Occ, PressureBefore.getOccupancy(ST));
+ LLVM_DEBUG(dbgs() << "Occupancy before scheduling: " << WavesBefore
+ << ", after " << WavesAfter << ".\n");
// We could not keep current target occupancy because of the just scheduled
// region. Record new occupancy for next scheduling cycle.
unsigned NewOccupancy = std::max(WavesAfter, WavesBefore);
+ // Allow memory bound functions to drop to 4 waves if not limited by an
+ // attribute.
+ if (WavesAfter < WavesBefore && WavesAfter < MinOccupancy &&
+ WavesAfter >= MFI.getMinAllowedOccupancy()) {
+ LLVM_DEBUG(dbgs() << "Function is memory bound, allow occupancy drop up to "
+ << MFI.getMinAllowedOccupancy() << " waves\n");
+ NewOccupancy = WavesAfter;
+ }
if (NewOccupancy < MinOccupancy) {
MinOccupancy = NewOccupancy;
- DEBUG(dbgs() << "Occupancy lowered for the function to "
- << MinOccupancy << ".\n");
+ MFI.limitOccupancy(MinOccupancy);
+ LLVM_DEBUG(dbgs() << "Occupancy lowered for the function to "
+ << MinOccupancy << ".\n");
}
- if (WavesAfter >= WavesBefore) {
+ if (WavesAfter >= MinOccupancy) {
Pressure[RegionIdx] = PressureAfter;
return;
}
- DEBUG(dbgs() << "Attempting to revert scheduling.\n");
+ LLVM_DEBUG(dbgs() << "Attempting to revert scheduling.\n");
RegionEnd = RegionBegin;
for (MachineInstr *MI : Unsched) {
- if (MI->isDebugValue())
+ if (MI->isDebugInstr())
continue;
if (MI->getIterator() != RegionEnd) {
BB->remove(MI);
BB->insert(RegionEnd, MI);
- if (!MI->isDebugValue())
+ if (!MI->isDebugInstr())
LIS->handleMove(*MI, true);
}
// Reset read-undef flags and update them later.
@@ -403,7 +393,7 @@ void GCNScheduleDAGMILive::schedule() {
Op.setIsUndef(false);
RegisterOperands RegOpers;
RegOpers.collect(*MI, *TRI, MRI, ShouldTrackLaneMasks, false);
- if (!MI->isDebugValue()) {
+ if (!MI->isDebugInstr()) {
if (ShouldTrackLaneMasks) {
// Adjust liveness and add missing dead+read-undef flags.
SlotIndex SlotIdx = LIS->getInstructionIndex(*MI).getRegSlot();
@@ -415,7 +405,7 @@ void GCNScheduleDAGMILive::schedule() {
}
RegionEnd = MI->getIterator();
++RegionEnd;
- DEBUG(dbgs() << "Scheduling " << *MI);
+ LLVM_DEBUG(dbgs() << "Scheduling " << *MI);
}
RegionBegin = Unsched.front()->getIterator();
Regions[RegionIdx] = std::make_pair(RegionBegin, RegionEnd);
@@ -490,7 +480,7 @@ void GCNScheduleDAGMILive::computeBlockPressure(const MachineBasicBlock *MBB) {
void GCNScheduleDAGMILive::finalizeSchedule() {
GCNMaxOccupancySchedStrategy &S = (GCNMaxOccupancySchedStrategy&)*SchedImpl;
- DEBUG(dbgs() << "All regions recorded, starting actual scheduling.\n");
+ LLVM_DEBUG(dbgs() << "All regions recorded, starting actual scheduling.\n");
LiveIns.resize(Regions.size());
Pressure.resize(Regions.size());
@@ -509,9 +499,10 @@ void GCNScheduleDAGMILive::finalizeSchedule() {
if (!LIS || StartingOccupancy <= MinOccupancy)
break;
- DEBUG(dbgs()
- << "Retrying function scheduling with lowest recorded occupancy "
- << MinOccupancy << ".\n");
+ LLVM_DEBUG(
+ dbgs()
+ << "Retrying function scheduling with lowest recorded occupancy "
+ << MinOccupancy << ".\n");
S.setTargetOccupancy(MinOccupancy);
}
@@ -537,12 +528,13 @@ void GCNScheduleDAGMILive::finalizeSchedule() {
continue;
}
- DEBUG(dbgs() << "********** MI Scheduling **********\n");
- DEBUG(dbgs() << MF.getName() << ":" << printMBBReference(*MBB) << " "
- << MBB->getName() << "\n From: " << *begin() << " To: ";
- if (RegionEnd != MBB->end()) dbgs() << *RegionEnd;
- else dbgs() << "End";
- dbgs() << " RegionInstrs: " << NumRegionInstrs << '\n');
+ LLVM_DEBUG(dbgs() << "********** MI Scheduling **********\n");
+ LLVM_DEBUG(dbgs() << MF.getName() << ":" << printMBBReference(*MBB) << " "
+ << MBB->getName() << "\n From: " << *begin()
+ << " To: ";
+ if (RegionEnd != MBB->end()) dbgs() << *RegionEnd;
+ else dbgs() << "End";
+ dbgs() << " RegionInstrs: " << NumRegionInstrs << '\n');
schedule();
generated by cgit v1.3 (git 2.53.0) at 2026-05-13 02:34:53 +0000