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diff --git a/llvm/lib/Target/AMDGPU/GCNIterativeScheduler.cpp b/llvm/lib/Target/AMDGPU/GCNIterativeScheduler.cpp
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+++ b/llvm/lib/Target/AMDGPU/GCNIterativeScheduler.cpp
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+//===- GCNIterativeScheduler.cpp ------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "GCNIterativeScheduler.h"
+#include "AMDGPUSubtarget.h"
+#include "GCNRegPressure.h"
+#include "GCNSchedStrategy.h"
+#include "SIMachineFunctionInfo.h"
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/CodeGen/LiveIntervals.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/RegisterPressure.h"
+#include "llvm/CodeGen/ScheduleDAG.h"
+#include "llvm/Config/llvm-config.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+#include <cassert>
+#include <iterator>
+#include <limits>
+#include <memory>
+#include <type_traits>
+#include <vector>
+
+using namespace llvm;
+
+#define DEBUG_TYPE "machine-scheduler"
+
+namespace llvm {
+
+std::vector<const SUnit *> makeMinRegSchedule(ArrayRef<const SUnit *> TopRoots,
+ const ScheduleDAG &DAG);
+
+ std::vector<const SUnit*> makeGCNILPScheduler(ArrayRef<const SUnit*> BotRoots,
+ const ScheduleDAG &DAG);
+}
+
+// shim accessors for different order containers
+static inline MachineInstr *getMachineInstr(MachineInstr *MI) {
+ return MI;
+}
+static inline MachineInstr *getMachineInstr(const SUnit *SU) {
+ return SU->getInstr();
+}
+static inline MachineInstr *getMachineInstr(const SUnit &SU) {
+ return SU.getInstr();
+}
+
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
+LLVM_DUMP_METHOD
+static void printRegion(raw_ostream &OS,
+ MachineBasicBlock::iterator Begin,
+ MachineBasicBlock::iterator End,
+ const LiveIntervals *LIS,
+ unsigned MaxInstNum =
+ std::numeric_limits<unsigned>::max()) {
+ auto BB = Begin->getParent();
+ OS << BB->getParent()->getName() << ":" << printMBBReference(*BB) << ' '
+ << BB->getName() << ":\n";
+ auto I = Begin;
+ MaxInstNum = std::max(MaxInstNum, 1u);
+ for (; I != End && MaxInstNum; ++I, --MaxInstNum) {
+ if (!I->isDebugInstr() && LIS)
+ OS << LIS->getInstructionIndex(*I);
+ OS << '\t' << *I;
+ }
+ if (I != End) {
+ OS << "\t...\n";
+ I = std::prev(End);
+ if (!I->isDebugInstr() && LIS)
+ OS << LIS->getInstructionIndex(*I);
+ OS << '\t' << *I;
+ }
+ if (End != BB->end()) { // print boundary inst if present
+ OS << "----\n";
+ if (LIS) OS << LIS->getInstructionIndex(*End) << '\t';
+ OS << *End;
+ }
+}
+
+LLVM_DUMP_METHOD
+static void printLivenessInfo(raw_ostream &OS,
+ MachineBasicBlock::iterator Begin,
+ MachineBasicBlock::iterator End,
+ const LiveIntervals *LIS) {
+ const auto BB = Begin->getParent();
+ const auto &MRI = BB->getParent()->getRegInfo();
+
+ const auto LiveIns = getLiveRegsBefore(*Begin, *LIS);
+ OS << "LIn RP: ";
+ getRegPressure(MRI, LiveIns).print(OS);
+
+ const auto BottomMI = End == BB->end() ? std::prev(End) : End;
+ const auto LiveOuts = getLiveRegsAfter(*BottomMI, *LIS);
+ OS << "LOt RP: ";
+ getRegPressure(MRI, LiveOuts).print(OS);
+}
+
+LLVM_DUMP_METHOD
+void GCNIterativeScheduler::printRegions(raw_ostream &OS) const {
+ const auto &ST = MF.getSubtarget<GCNSubtarget>();
+ for (const auto R : Regions) {
+ OS << "Region to schedule ";
+ printRegion(OS, R->Begin, R->End, LIS, 1);
+ printLivenessInfo(OS, R->Begin, R->End, LIS);
+ OS << "Max RP: ";
+ R->MaxPressure.print(OS, &ST);
+ }
+}
+
+LLVM_DUMP_METHOD
+void GCNIterativeScheduler::printSchedResult(raw_ostream &OS,
+ const Region *R,
+ const GCNRegPressure &RP) const {
+ OS << "\nAfter scheduling ";
+ printRegion(OS, R->Begin, R->End, LIS);
+ printSchedRP(OS, R->MaxPressure, RP);
+ OS << '\n';
+}
+
+LLVM_DUMP_METHOD
+void GCNIterativeScheduler::printSchedRP(raw_ostream &OS,
+ const GCNRegPressure &Before,
+ const GCNRegPressure &After) const {
+ const auto &ST = MF.getSubtarget<GCNSubtarget>();
+ OS << "RP before: ";
+ Before.print(OS, &ST);
+ OS << "RP after: ";
+ After.print(OS, &ST);
+}
+#endif
+
+// DAG builder helper
+class GCNIterativeScheduler::BuildDAG {
+ GCNIterativeScheduler &Sch;
+ SmallVector<SUnit *, 8> TopRoots;
+
+ SmallVector<SUnit*, 8> BotRoots;
+public:
+ BuildDAG(const Region &R, GCNIterativeScheduler &_Sch)
+ : Sch(_Sch) {
+ auto BB = R.Begin->getParent();
+ Sch.BaseClass::startBlock(BB);
+ Sch.BaseClass::enterRegion(BB, R.Begin, R.End, R.NumRegionInstrs);
+
+ Sch.buildSchedGraph(Sch.AA, nullptr, nullptr, nullptr,
+ /*TrackLaneMask*/true);
+ Sch.Topo.InitDAGTopologicalSorting();
+ Sch.findRootsAndBiasEdges(TopRoots, BotRoots);
+ }
+
+ ~BuildDAG() {
+ Sch.BaseClass::exitRegion();
+ Sch.BaseClass::finishBlock();
+ }
+
+ ArrayRef<const SUnit *> getTopRoots() const {
+ return TopRoots;
+ }
+ ArrayRef<SUnit*> getBottomRoots() const {
+ return BotRoots;
+ }
+};
+
+class GCNIterativeScheduler::OverrideLegacyStrategy {
+ GCNIterativeScheduler &Sch;
+ Region &Rgn;
+ std::unique_ptr<MachineSchedStrategy> SaveSchedImpl;
+ GCNRegPressure SaveMaxRP;
+
+public:
+ OverrideLegacyStrategy(Region &R,
+ MachineSchedStrategy &OverrideStrategy,
+ GCNIterativeScheduler &_Sch)
+ : Sch(_Sch)
+ , Rgn(R)
+ , SaveSchedImpl(std::move(_Sch.SchedImpl))
+ , SaveMaxRP(R.MaxPressure) {
+ Sch.SchedImpl.reset(&OverrideStrategy);
+ auto BB = R.Begin->getParent();
+ Sch.BaseClass::startBlock(BB);
+ Sch.BaseClass::enterRegion(BB, R.Begin, R.End, R.NumRegionInstrs);
+ }
+
+ ~OverrideLegacyStrategy() {
+ Sch.BaseClass::exitRegion();
+ Sch.BaseClass::finishBlock();
+ Sch.SchedImpl.release();
+ Sch.SchedImpl = std::move(SaveSchedImpl);
+ }
+
+ void schedule() {
+ assert(Sch.RegionBegin == Rgn.Begin && Sch.RegionEnd == Rgn.End);
+ LLVM_DEBUG(dbgs() << "\nScheduling ";
+ printRegion(dbgs(), Rgn.Begin, Rgn.End, Sch.LIS, 2));
+ Sch.BaseClass::schedule();
+
+ // Unfortunatelly placeDebugValues incorrectly modifies RegionEnd, restore
+ Sch.RegionEnd = Rgn.End;
+ //assert(Rgn.End == Sch.RegionEnd);
+ Rgn.Begin = Sch.RegionBegin;
+ Rgn.MaxPressure.clear();
+ }
+
+ void restoreOrder() {
+ assert(Sch.RegionBegin == Rgn.Begin && Sch.RegionEnd == Rgn.End);
+ // DAG SUnits are stored using original region's order
+ // so just use SUnits as the restoring schedule
+ Sch.scheduleRegion(Rgn, Sch.SUnits, SaveMaxRP);
+ }
+};
+
+namespace {
+
+// just a stub to make base class happy
+class SchedStrategyStub : public MachineSchedStrategy {
+public:
+ bool shouldTrackPressure() const override { return false; }
+ bool shouldTrackLaneMasks() const override { return false; }
+ void initialize(ScheduleDAGMI *DAG) override {}
+ SUnit *pickNode(bool &IsTopNode) override { return nullptr; }
+ void schedNode(SUnit *SU, bool IsTopNode) override {}
+ void releaseTopNode(SUnit *SU) override {}
+ void releaseBottomNode(SUnit *SU) override {}
+};
+
+} // end anonymous namespace
+
+GCNIterativeScheduler::GCNIterativeScheduler(MachineSchedContext *C,
+ StrategyKind S)
+ : BaseClass(C, std::make_unique<SchedStrategyStub>())
+ , Context(C)
+ , Strategy(S)
+ , UPTracker(*LIS) {
+}
+
+// returns max pressure for a region
+GCNRegPressure
+GCNIterativeScheduler::getRegionPressure(MachineBasicBlock::iterator Begin,
+ MachineBasicBlock::iterator End)
+ const {
+ // For the purpose of pressure tracking bottom inst of the region should
+ // be also processed. End is either BB end, BB terminator inst or sched
+ // boundary inst.
+ auto const BBEnd = Begin->getParent()->end();
+ auto const BottomMI = End == BBEnd ? std::prev(End) : End;
+
+ // scheduleRegions walks bottom to top, so its likely we just get next
+ // instruction to track
+ auto AfterBottomMI = std::next(BottomMI);
+ if (AfterBottomMI == BBEnd ||
+ &*AfterBottomMI != UPTracker.getLastTrackedMI()) {
+ UPTracker.reset(*BottomMI);
+ } else {
+ assert(UPTracker.isValid());
+ }
+
+ for (auto I = BottomMI; I != Begin; --I)
+ UPTracker.recede(*I);
+
+ UPTracker.recede(*Begin);
+
+ assert(UPTracker.isValid() ||
+ (dbgs() << "Tracked region ",
+ printRegion(dbgs(), Begin, End, LIS), false));
+ return UPTracker.moveMaxPressure();
+}
+
+// returns max pressure for a tentative schedule
+template <typename Range> GCNRegPressure
+GCNIterativeScheduler::getSchedulePressure(const Region &R,
+ Range &&Schedule) const {
+ auto const BBEnd = R.Begin->getParent()->end();
+ GCNUpwardRPTracker RPTracker(*LIS);
+ if (R.End != BBEnd) {
+ // R.End points to the boundary instruction but the
+ // schedule doesn't include it
+ RPTracker.reset(*R.End);
+ RPTracker.recede(*R.End);
+ } else {
+ // R.End doesn't point to the boundary instruction
+ RPTracker.reset(*std::prev(BBEnd));
+ }
+ for (auto I = Schedule.end(), B = Schedule.begin(); I != B;) {
+ RPTracker.recede(*getMachineInstr(*--I));
+ }
+ return RPTracker.moveMaxPressure();
+}
+
+void GCNIterativeScheduler::enterRegion(MachineBasicBlock *BB, // overriden
+ MachineBasicBlock::iterator Begin,
+ MachineBasicBlock::iterator End,
+ unsigned NumRegionInstrs) {
+ BaseClass::enterRegion(BB, Begin, End, NumRegionInstrs);
+ if (NumRegionInstrs > 2) {
+ Regions.push_back(
+ new (Alloc.Allocate())
+ Region { Begin, End, NumRegionInstrs,
+ getRegionPressure(Begin, End), nullptr });
+ }
+}
+
+void GCNIterativeScheduler::schedule() { // overriden
+ // do nothing
+ LLVM_DEBUG(printLivenessInfo(dbgs(), RegionBegin, RegionEnd, LIS);
+ if (!Regions.empty() && Regions.back()->Begin == RegionBegin) {
+ dbgs() << "Max RP: ";
+ Regions.back()->MaxPressure.print(
+ dbgs(), &MF.getSubtarget<GCNSubtarget>());
+ } dbgs()
+ << '\n';);
+}
+
+void GCNIterativeScheduler::finalizeSchedule() { // overriden
+ if (Regions.empty())
+ return;
+ switch (Strategy) {
+ case SCHEDULE_MINREGONLY: scheduleMinReg(); break;
+ case SCHEDULE_MINREGFORCED: scheduleMinReg(true); break;
+ case SCHEDULE_LEGACYMAXOCCUPANCY: scheduleLegacyMaxOccupancy(); break;
+ case SCHEDULE_ILP: scheduleILP(false); break;
+ }
+}
+
+// Detach schedule from SUnits and interleave it with debug values.
+// Returned schedule becomes independent of DAG state.
+std::vector<MachineInstr*>
+GCNIterativeScheduler::detachSchedule(ScheduleRef Schedule) const {
+ std::vector<MachineInstr*> Res;
+ Res.reserve(Schedule.size() * 2);
+
+ if (FirstDbgValue)
+ Res.push_back(FirstDbgValue);
+
+ const auto DbgB = DbgValues.begin(), DbgE = DbgValues.end();
+ for (auto SU : Schedule) {
+ Res.push_back(SU->getInstr());
+ const auto &D = std::find_if(DbgB, DbgE, [SU](decltype(*DbgB) &P) {
+ return P.second == SU->getInstr();
+ });
+ if (D != DbgE)
+ Res.push_back(D->first);
+ }
+ return Res;
+}
+
+void GCNIterativeScheduler::setBestSchedule(Region &R,
+ ScheduleRef Schedule,
+ const GCNRegPressure &MaxRP) {
+ R.BestSchedule.reset(
+ new TentativeSchedule{ detachSchedule(Schedule), MaxRP });
+}
+
+void GCNIterativeScheduler::scheduleBest(Region &R) {
+ assert(R.BestSchedule.get() && "No schedule specified");
+ scheduleRegion(R, R.BestSchedule->Schedule, R.BestSchedule->MaxPressure);
+ R.BestSchedule.reset();
+}
+
+// minimal required region scheduler, works for ranges of SUnits*,
+// SUnits or MachineIntrs*
+template <typename Range>
+void GCNIterativeScheduler::scheduleRegion(Region &R, Range &&Schedule,
+ const GCNRegPressure &MaxRP) {
+ assert(RegionBegin == R.Begin && RegionEnd == R.End);
+ assert(LIS != nullptr);
+#ifndef NDEBUG
+ const auto SchedMaxRP = getSchedulePressure(R, Schedule);
+#endif
+ auto BB = R.Begin->getParent();
+ auto Top = R.Begin;
+ for (const auto &I : Schedule) {
+ auto MI = getMachineInstr(I);
+ if (MI != &*Top) {
+ BB->remove(MI);
+ BB->insert(Top, MI);
+ if (!MI->isDebugInstr())
+ LIS->handleMove(*MI, true);
+ }
+ if (!MI->isDebugInstr()) {
+ // Reset read - undef flags and update them later.
+ for (auto &Op : MI->operands())
+ if (Op.isReg() && Op.isDef())
+ Op.setIsUndef(false);
+
+ RegisterOperands RegOpers;
+ RegOpers.collect(*MI, *TRI, MRI, /*ShouldTrackLaneMasks*/true,
+ /*IgnoreDead*/false);
+ // Adjust liveness and add missing dead+read-undef flags.
+ auto SlotIdx = LIS->getInstructionIndex(*MI).getRegSlot();
+ RegOpers.adjustLaneLiveness(*LIS, MRI, SlotIdx, MI);
+ }
+ Top = std::next(MI->getIterator());
+ }
+ RegionBegin = getMachineInstr(Schedule.front());
+
+ // Schedule consisting of MachineInstr* is considered 'detached'
+ // and already interleaved with debug values
+ if (!std::is_same<decltype(*Schedule.begin()), MachineInstr*>::value) {
+ placeDebugValues();
+ // Unfortunatelly placeDebugValues incorrectly modifies RegionEnd, restore
+ //assert(R.End == RegionEnd);
+ RegionEnd = R.End;
+ }
+
+ R.Begin = RegionBegin;
+ R.MaxPressure = MaxRP;
+
+#ifndef NDEBUG
+ const auto RegionMaxRP = getRegionPressure(R);
+ const auto &ST = MF.getSubtarget<GCNSubtarget>();
+#endif
+ assert((SchedMaxRP == RegionMaxRP && (MaxRP.empty() || SchedMaxRP == MaxRP))
+ || (dbgs() << "Max RP mismatch!!!\n"
+ "RP for schedule (calculated): ",
+ SchedMaxRP.print(dbgs(), &ST),
+ dbgs() << "RP for schedule (reported): ",
+ MaxRP.print(dbgs(), &ST),
+ dbgs() << "RP after scheduling: ",
+ RegionMaxRP.print(dbgs(), &ST),
+ false));
+}
+
+// Sort recorded regions by pressure - highest at the front
+void GCNIterativeScheduler::sortRegionsByPressure(unsigned TargetOcc) {
+ const auto &ST = MF.getSubtarget<GCNSubtarget>();
+ llvm::sort(Regions, [&ST, TargetOcc](const Region *R1, const Region *R2) {
+ return R2->MaxPressure.less(ST, R1->MaxPressure, TargetOcc);
+ });
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Legacy MaxOccupancy Strategy
+
+// Tries to increase occupancy applying minreg scheduler for a sequence of
+// most demanding regions. Obtained schedules are saved as BestSchedule for a
+// region.
+// TargetOcc is the best achievable occupancy for a kernel.
+// Returns better occupancy on success or current occupancy on fail.
+// BestSchedules aren't deleted on fail.
+unsigned GCNIterativeScheduler::tryMaximizeOccupancy(unsigned TargetOcc) {
+ // TODO: assert Regions are sorted descending by pressure
+ const auto &ST = MF.getSubtarget<GCNSubtarget>();
+ const auto Occ = Regions.front()->MaxPressure.getOccupancy(ST);
+ LLVM_DEBUG(dbgs() << "Trying to improve occupancy, target = " << TargetOcc
+ << ", current = " << Occ << '\n');
+
+ auto NewOcc = TargetOcc;
+ for (auto R : Regions) {
+ if (R->MaxPressure.getOccupancy(ST) >= NewOcc)
+ break;
+
+ LLVM_DEBUG(printRegion(dbgs(), R->Begin, R->End, LIS, 3);
+ printLivenessInfo(dbgs(), R->Begin, R->End, LIS));
+
+ BuildDAG DAG(*R, *this);
+ const auto MinSchedule = makeMinRegSchedule(DAG.getTopRoots(), *this);
+ const auto MaxRP = getSchedulePressure(*R, MinSchedule);
+ LLVM_DEBUG(dbgs() << "Occupancy improvement attempt:\n";
+ printSchedRP(dbgs(), R->MaxPressure, MaxRP));
+
+ NewOcc = std::min(NewOcc, MaxRP.getOccupancy(ST));
+ if (NewOcc <= Occ)
+ break;
+
+ setBestSchedule(*R, MinSchedule, MaxRP);
+ }
+ LLVM_DEBUG(dbgs() << "New occupancy = " << NewOcc
+ << ", prev occupancy = " << Occ << '\n');
+ if (NewOcc > Occ) {
+ SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
+ MFI->increaseOccupancy(MF, NewOcc);
+ }
+
+ return std::max(NewOcc, Occ);
+}
+
+void GCNIterativeScheduler::scheduleLegacyMaxOccupancy(
+ bool TryMaximizeOccupancy) {
+ const auto &ST = MF.getSubtarget<GCNSubtarget>();
+ SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
+ auto TgtOcc = MFI->getMinAllowedOccupancy();
+
+ sortRegionsByPressure(TgtOcc);
+ auto Occ = Regions.front()->MaxPressure.getOccupancy(ST);
+
+ if (TryMaximizeOccupancy && Occ < TgtOcc)
+ Occ = tryMaximizeOccupancy(TgtOcc);
+
+ // This is really weird but for some magic scheduling regions twice
+ // gives performance improvement
+ const int NumPasses = Occ < TgtOcc ? 2 : 1;
+
+ TgtOcc = std::min(Occ, TgtOcc);
+ LLVM_DEBUG(dbgs() << "Scheduling using default scheduler, "
+ "target occupancy = "
+ << TgtOcc << '\n');
+ GCNMaxOccupancySchedStrategy LStrgy(Context);
+ unsigned FinalOccupancy = std::min(Occ, MFI->getOccupancy());
+
+ for (int I = 0; I < NumPasses; ++I) {
+ // running first pass with TargetOccupancy = 0 mimics previous scheduling
+ // approach and is a performance magic
+ LStrgy.setTargetOccupancy(I == 0 ? 0 : TgtOcc);
+ for (auto R : Regions) {
+ OverrideLegacyStrategy Ovr(*R, LStrgy, *this);
+
+ Ovr.schedule();
+ const auto RP = getRegionPressure(*R);
+ LLVM_DEBUG(printSchedRP(dbgs(), R->MaxPressure, RP));
+
+ if (RP.getOccupancy(ST) < TgtOcc) {
+ LLVM_DEBUG(dbgs() << "Didn't fit into target occupancy O" << TgtOcc);
+ if (R->BestSchedule.get() &&
+ R->BestSchedule->MaxPressure.getOccupancy(ST) >= TgtOcc) {
+ LLVM_DEBUG(dbgs() << ", scheduling minimal register\n");
+ scheduleBest(*R);
+ } else {
+ LLVM_DEBUG(dbgs() << ", restoring\n");
+ Ovr.restoreOrder();
+ assert(R->MaxPressure.getOccupancy(ST) >= TgtOcc);
+ }
+ }
+ FinalOccupancy = std::min(FinalOccupancy, RP.getOccupancy(ST));
+ }
+ }
+ MFI->limitOccupancy(FinalOccupancy);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Minimal Register Strategy
+
+void GCNIterativeScheduler::scheduleMinReg(bool force) {
+ const auto &ST = MF.getSubtarget<GCNSubtarget>();
+ const SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
+ const auto TgtOcc = MFI->getOccupancy();
+ sortRegionsByPressure(TgtOcc);
+
+ auto MaxPressure = Regions.front()->MaxPressure;
+ for (auto R : Regions) {
+ if (!force && R->MaxPressure.less(ST, MaxPressure, TgtOcc))
+ break;
+
+ BuildDAG DAG(*R, *this);
+ const auto MinSchedule = makeMinRegSchedule(DAG.getTopRoots(), *this);
+
+ const auto RP = getSchedulePressure(*R, MinSchedule);
+ LLVM_DEBUG(if (R->MaxPressure.less(ST, RP, TgtOcc)) {
+ dbgs() << "\nWarning: Pressure becomes worse after minreg!";
+ printSchedRP(dbgs(), R->MaxPressure, RP);
+ });
+
+ if (!force && MaxPressure.less(ST, RP, TgtOcc))
+ break;
+
+ scheduleRegion(*R, MinSchedule, RP);
+ LLVM_DEBUG(printSchedResult(dbgs(), R, RP));
+
+ MaxPressure = RP;
+ }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// ILP scheduler port
+
+void GCNIterativeScheduler::scheduleILP(
+ bool TryMaximizeOccupancy) {
+ const auto &ST = MF.getSubtarget<GCNSubtarget>();
+ SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
+ auto TgtOcc = MFI->getMinAllowedOccupancy();
+
+ sortRegionsByPressure(TgtOcc);
+ auto Occ = Regions.front()->MaxPressure.getOccupancy(ST);
+
+ if (TryMaximizeOccupancy && Occ < TgtOcc)
+ Occ = tryMaximizeOccupancy(TgtOcc);
+
+ TgtOcc = std::min(Occ, TgtOcc);
+ LLVM_DEBUG(dbgs() << "Scheduling using default scheduler, "
+ "target occupancy = "
+ << TgtOcc << '\n');
+
+ unsigned FinalOccupancy = std::min(Occ, MFI->getOccupancy());
+ for (auto R : Regions) {
+ BuildDAG DAG(*R, *this);
+ const auto ILPSchedule = makeGCNILPScheduler(DAG.getBottomRoots(), *this);
+
+ const auto RP = getSchedulePressure(*R, ILPSchedule);
+ LLVM_DEBUG(printSchedRP(dbgs(), R->MaxPressure, RP));
+
+ if (RP.getOccupancy(ST) < TgtOcc) {
+ LLVM_DEBUG(dbgs() << "Didn't fit into target occupancy O" << TgtOcc);
+ if (R->BestSchedule.get() &&
+ R->BestSchedule->MaxPressure.getOccupancy(ST) >= TgtOcc) {
+ LLVM_DEBUG(dbgs() << ", scheduling minimal register\n");
+ scheduleBest(*R);
+ }
+ } else {
+ scheduleRegion(*R, ILPSchedule, RP);
+ LLVM_DEBUG(printSchedResult(dbgs(), R, RP));
+ FinalOccupancy = std::min(FinalOccupancy, RP.getOccupancy(ST));
+ }
+ }
+ MFI->limitOccupancy(FinalOccupancy);
+}