#include "AntiDepBreaker.h"
#include "AggressiveAntiDepBreaker.h"
#include "CriticalAntiDepBreaker.h"
-#include "ExactHazardRecognizer.h"
-#include "SimpleHazardRecognizer.h"
+#include "RegisterClassInfo.h"
#include "ScheduleDAGInstrs.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/CodeGen/LatencyPriorityQueue.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetRegisterInfo.h"
-#include "llvm/Target/TargetSubtarget.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
STATISTIC(NumFixedAnti, "Number of fixed anti-dependencies");
// Post-RA scheduling is enabled with
-// TargetSubtarget.enablePostRAScheduler(). This flag can be used to
+// TargetSubtargetInfo.enablePostRAScheduler(). This flag can be used to
// override the target.
static cl::opt<bool>
EnablePostRAScheduler("post-RA-scheduler",
cl::desc("Break post-RA scheduling anti-dependencies: "
"\"critical\", \"all\", or \"none\""),
cl::init("none"), cl::Hidden);
-static cl::opt<bool>
-EnablePostRAHazardAvoidance("avoid-hazards",
- cl::desc("Enable exact hazard avoidance"),
- cl::init(true), cl::Hidden);
// If DebugDiv > 0 then only schedule MBB with (ID % DebugDiv) == DebugMod
static cl::opt<int>
cl::desc("Debug control MBBs that are scheduled"),
cl::init(0), cl::Hidden);
-static cl::opt<bool>
-EnablePostRADbgValue("post-RA-dbg-value",
- cl::desc("Enable processing of dbg_value in post-RA"),
- cl::init(true), cl::Hidden);
-
-
AntiDepBreaker::~AntiDepBreaker() { }
namespace {
class PostRAScheduler : public MachineFunctionPass {
AliasAnalysis *AA;
+ const TargetInstrInfo *TII;
+ RegisterClassInfo RegClassInfo;
CodeGenOpt::Level OptLevel;
public:
static char ID;
PostRAScheduler(CodeGenOpt::Level ol) :
- MachineFunctionPass(&ID), OptLevel(ol) {}
+ MachineFunctionPass(ID), OptLevel(ol) {}
void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesCFG();
/// KillIndices - The index of the most recent kill (proceding bottom-up),
/// or ~0u if the register is not live.
- unsigned KillIndices[TargetRegisterInfo::FirstVirtualRegister];
+ std::vector<unsigned> KillIndices;
public:
- SchedulePostRATDList(MachineFunction &MF,
- const MachineLoopInfo &MLI,
- const MachineDominatorTree &MDT,
- ScheduleHazardRecognizer *HR,
- AntiDepBreaker *ADB,
- AliasAnalysis *aa)
- : ScheduleDAGInstrs(MF, MLI, MDT), Topo(SUnits),
- HazardRec(HR), AntiDepBreak(ADB), AA(aa) {}
-
- ~SchedulePostRATDList() {
- }
+ SchedulePostRATDList(
+ MachineFunction &MF, MachineLoopInfo &MLI, MachineDominatorTree &MDT,
+ AliasAnalysis *AA, const RegisterClassInfo&,
+ TargetSubtargetInfo::AntiDepBreakMode AntiDepMode,
+ SmallVectorImpl<TargetRegisterClass*> &CriticalPathRCs);
+
+ ~SchedulePostRATDList();
/// StartBlock - Initialize register live-range state for scheduling in
/// this block.
};
}
-/// isSchedulingBoundary - Test if the given instruction should be
-/// considered a scheduling boundary. This primarily includes labels
-/// and terminators.
-///
-static bool isSchedulingBoundary(const MachineInstr *MI,
- const MachineFunction &MF) {
- // Terminators and labels can't be scheduled around.
- if (MI->getDesc().isTerminator() || MI->isLabel())
- return true;
-
- // Don't attempt to schedule around any instruction that modifies
- // a stack-oriented pointer, as it's unlikely to be profitable. This
- // saves compile time, because it doesn't require every single
- // stack slot reference to depend on the instruction that does the
- // modification.
- const TargetLowering &TLI = *MF.getTarget().getTargetLowering();
- if (MI->modifiesRegister(TLI.getStackPointerRegisterToSaveRestore()))
- return true;
+SchedulePostRATDList::SchedulePostRATDList(
+ MachineFunction &MF, MachineLoopInfo &MLI, MachineDominatorTree &MDT,
+ AliasAnalysis *AA, const RegisterClassInfo &RCI,
+ TargetSubtargetInfo::AntiDepBreakMode AntiDepMode,
+ SmallVectorImpl<TargetRegisterClass*> &CriticalPathRCs)
+ : ScheduleDAGInstrs(MF, MLI, MDT), Topo(SUnits), AA(AA),
+ KillIndices(TRI->getNumRegs())
+{
+ const TargetMachine &TM = MF.getTarget();
+ const InstrItineraryData *InstrItins = TM.getInstrItineraryData();
+ HazardRec =
+ TM.getInstrInfo()->CreateTargetPostRAHazardRecognizer(InstrItins, this);
+ AntiDepBreak =
+ ((AntiDepMode == TargetSubtargetInfo::ANTIDEP_ALL) ?
+ (AntiDepBreaker *)new AggressiveAntiDepBreaker(MF, RCI, CriticalPathRCs) :
+ ((AntiDepMode == TargetSubtargetInfo::ANTIDEP_CRITICAL) ?
+ (AntiDepBreaker *)new CriticalAntiDepBreaker(MF, RCI) : NULL));
+}
- return false;
+SchedulePostRATDList::~SchedulePostRATDList() {
+ delete HazardRec;
+ delete AntiDepBreak;
}
bool PostRAScheduler::runOnMachineFunction(MachineFunction &Fn) {
- AA = &getAnalysis<AliasAnalysis>();
+ TII = Fn.getTarget().getInstrInfo();
+ MachineLoopInfo &MLI = getAnalysis<MachineLoopInfo>();
+ MachineDominatorTree &MDT = getAnalysis<MachineDominatorTree>();
+ AliasAnalysis *AA = &getAnalysis<AliasAnalysis>();
+ RegClassInfo.runOnMachineFunction(Fn);
// Check for explicit enable/disable of post-ra scheduling.
- TargetSubtarget::AntiDepBreakMode AntiDepMode = TargetSubtarget::ANTIDEP_NONE;
+ TargetSubtargetInfo::AntiDepBreakMode AntiDepMode = TargetSubtargetInfo::ANTIDEP_NONE;
SmallVector<TargetRegisterClass*, 4> CriticalPathRCs;
if (EnablePostRAScheduler.getPosition() > 0) {
if (!EnablePostRAScheduler)
return false;
} else {
// Check that post-RA scheduling is enabled for this target.
- const TargetSubtarget &ST = Fn.getTarget().getSubtarget<TargetSubtarget>();
+ // This may upgrade the AntiDepMode.
+ const TargetSubtargetInfo &ST = Fn.getTarget().getSubtarget<TargetSubtargetInfo>();
if (!ST.enablePostRAScheduler(OptLevel, AntiDepMode, CriticalPathRCs))
return false;
}
// Check for antidep breaking override...
if (EnableAntiDepBreaking.getPosition() > 0) {
- AntiDepMode = (EnableAntiDepBreaking == "all") ?
- TargetSubtarget::ANTIDEP_ALL :
- (EnableAntiDepBreaking == "critical")
- ? TargetSubtarget::ANTIDEP_CRITICAL : TargetSubtarget::ANTIDEP_NONE;
+ AntiDepMode = (EnableAntiDepBreaking == "all")
+ ? TargetSubtargetInfo::ANTIDEP_ALL
+ : ((EnableAntiDepBreaking == "critical")
+ ? TargetSubtargetInfo::ANTIDEP_CRITICAL
+ : TargetSubtargetInfo::ANTIDEP_NONE);
}
DEBUG(dbgs() << "PostRAScheduler\n");
- const MachineLoopInfo &MLI = getAnalysis<MachineLoopInfo>();
- const MachineDominatorTree &MDT = getAnalysis<MachineDominatorTree>();
- const InstrItineraryData &InstrItins = Fn.getTarget().getInstrItineraryData();
- ScheduleHazardRecognizer *HR = EnablePostRAHazardAvoidance ?
- (ScheduleHazardRecognizer *)new ExactHazardRecognizer(InstrItins) :
- (ScheduleHazardRecognizer *)new SimpleHazardRecognizer();
- AntiDepBreaker *ADB =
- ((AntiDepMode == TargetSubtarget::ANTIDEP_ALL) ?
- (AntiDepBreaker *)new AggressiveAntiDepBreaker(Fn, CriticalPathRCs) :
- ((AntiDepMode == TargetSubtarget::ANTIDEP_CRITICAL) ?
- (AntiDepBreaker *)new CriticalAntiDepBreaker(Fn) : NULL));
-
- SchedulePostRATDList Scheduler(Fn, MLI, MDT, HR, ADB, AA);
+ SchedulePostRATDList Scheduler(Fn, MLI, MDT, AA, RegClassInfo, AntiDepMode,
+ CriticalPathRCs);
// Loop over all of the basic blocks
for (MachineFunction::iterator MBB = Fn.begin(), MBBe = Fn.end();
static int bbcnt = 0;
if (bbcnt++ % DebugDiv != DebugMod)
continue;
- dbgs() << "*** DEBUG scheduling " << Fn.getFunction()->getNameStr() <<
- ":BB#" << MBB->getNumber() << " ***\n";
+ dbgs() << "*** DEBUG scheduling " << Fn.getFunction()->getName()
+ << ":BB#" << MBB->getNumber() << " ***\n";
}
#endif
// Initialize register live-range state for scheduling in this block.
Scheduler.StartBlock(MBB);
- // FIXME: Temporary workaround for <rdar://problem/7759363>: The post-RA
- // scheduler has some sort of problem with DebugValue instructions that
- // causes an assertion in LeaksContext.h to fail occasionally. Just
- // remove all those instructions for now.
- if (!EnablePostRADbgValue) {
- DEBUG(dbgs() << "*** Maintaining DbgValues in PostRAScheduler\n");
- for (MachineBasicBlock::iterator I = MBB->begin(), E = MBB->end();
- I != E; ) {
- MachineInstr *MI = &*I++;
- if (MI->isDebugValue())
- MI->eraseFromParent();
- }
- }
-
// Schedule each sequence of instructions not interrupted by a label
// or anything else that effectively needs to shut down scheduling.
MachineBasicBlock::iterator Current = MBB->end();
unsigned Count = MBB->size(), CurrentCount = Count;
for (MachineBasicBlock::iterator I = Current; I != MBB->begin(); ) {
- MachineInstr *MI = prior(I);
- if (isSchedulingBoundary(MI, Fn)) {
+ MachineInstr *MI = llvm::prior(I);
+ if (TII->isSchedulingBoundary(MI, MBB, Fn)) {
Scheduler.Run(MBB, I, Current, CurrentCount);
Scheduler.EmitSchedule();
Current = MI;
Scheduler.FixupKills(MBB);
}
- delete HR;
- delete ADB;
-
return true;
}
if (AntiDepBreak != NULL) {
unsigned Broken =
AntiDepBreak->BreakAntiDependencies(SUnits, Begin, InsertPos,
- InsertPosIndex);
+ InsertPosIndex, DbgValues);
if (Broken != 0) {
// We made changes. Update the dependency graph.
KillIndices[i] = ~0u;
// Determine the live-out physregs for this block.
- if (!BB->empty() && BB->back().getDesc().isReturn()) {
+ if (!BB->empty() && BB->back().isReturn()) {
// In a return block, examine the function live-out regs.
for (MachineRegisterInfo::liveout_iterator I = MRI.liveout_begin(),
E = MRI.liveout_end(); I != E; ++I) {
#endif
--SuccSU->NumPredsLeft;
- // Compute how many cycles it will be before this actually becomes
- // available. This is the max of the start time of all predecessors plus
- // their latencies.
- SuccSU->setDepthToAtLeast(SU->getDepth() + SuccEdge->getLatency());
+ // Standard scheduler algorithms will recompute the depth of the successor
+ // here as such:
+ // SuccSU->setDepthToAtLeast(SU->getDepth() + SuccEdge->getLatency());
+ //
+ // However, we lazily compute node depth instead. Note that
+ // ScheduleNodeTopDown has already updated the depth of this node which causes
+ // all descendents to be marked dirty. Setting the successor depth explicitly
+ // here would cause depth to be recomputed for all its ancestors. If the
+ // successor is not yet ready (because of a transitively redundant edge) then
+ // this causes depth computation to be quadratic in the size of the DAG.
// If all the node's predecessors are scheduled, this node is ready
// to be scheduled. Ignore the special ExitSU node.
MinDepth = PendingQueue[i]->getDepth();
}
- DEBUG(dbgs() << "\n*** Examining Available\n";
- LatencyPriorityQueue q = AvailableQueue;
- while (!q.empty()) {
- SUnit *su = q.pop();
- dbgs() << "Height " << su->getHeight() << ": ";
- su->dump(this);
- });
+ DEBUG(dbgs() << "\n*** Examining Available\n"; AvailableQueue.dump(this));
SUnit *FoundSUnit = 0;
bool HasNoopHazards = false;
SUnit *CurSUnit = AvailableQueue.pop();
ScheduleHazardRecognizer::HazardType HT =
- HazardRec->getHazardType(CurSUnit);
+ HazardRec->getHazardType(CurSUnit, 0/*no stalls*/);
if (HT == ScheduleHazardRecognizer::NoHazard) {
FoundSUnit = CurSUnit;
break;
ScheduleNodeTopDown(FoundSUnit, CurCycle);
HazardRec->EmitInstruction(FoundSUnit);
CycleHasInsts = true;
-
- // If we are using the target-specific hazards, then don't
- // advance the cycle time just because we schedule a node. If
- // the target allows it we can schedule multiple nodes in the
- // same cycle.
- if (!EnablePostRAHazardAvoidance) {
- if (FoundSUnit->Latency) // Don't increment CurCycle for pseudo-ops!
- ++CurCycle;
+ if (HazardRec->atIssueLimit()) {
+ DEBUG(dbgs() << "*** Max instructions per cycle " << CurCycle << '\n');
+ HazardRec->AdvanceCycle();
+ ++CurCycle;
+ CycleHasInsts = false;
}
} else {
if (CycleHasInsts) {