//
//===----------------------------------------------------------------------===//
-#ifndef SCHEDULEDAGINSTRS_H
-#define SCHEDULEDAGINSTRS_H
+#ifndef LLVM_CODEGEN_SCHEDULEDAGINSTRS_H
+#define LLVM_CODEGEN_SCHEDULEDAGINSTRS_H
-#include "llvm/CodeGen/MachineDominators.h"
-#include "llvm/CodeGen/MachineLoopInfo.h"
+#include "llvm/ADT/SparseMultiSet.h"
+#include "llvm/ADT/SparseSet.h"
#include "llvm/CodeGen/ScheduleDAG.h"
+#include "llvm/CodeGen/TargetSchedule.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Target/TargetRegisterInfo.h"
-#include "llvm/ADT/SmallSet.h"
-#include "llvm/ADT/SparseSet.h"
-#include <map>
namespace llvm {
+ class MachineFrameInfo;
class MachineLoopInfo;
class MachineDominatorTree;
class LiveIntervals;
class RegPressureTracker;
-
- /// LoopDependencies - This class analyzes loop-oriented register
- /// dependencies, which are used to guide scheduling decisions.
- /// For example, loop induction variable increments should be
- /// scheduled as soon as possible after the variable's last use.
- ///
- class LoopDependencies {
- const MachineLoopInfo &MLI;
- const MachineDominatorTree &MDT;
-
- public:
- typedef std::map<unsigned, std::pair<const MachineOperand *, unsigned> >
- LoopDeps;
- LoopDeps Deps;
-
- LoopDependencies(const MachineLoopInfo &mli,
- const MachineDominatorTree &mdt) :
- MLI(mli), MDT(mdt) {}
-
- /// VisitLoop - Clear out any previous state and analyze the given loop.
- ///
- void VisitLoop(const MachineLoop *Loop) {
- assert(Deps.empty() && "stale loop dependencies");
-
- MachineBasicBlock *Header = Loop->getHeader();
- SmallSet<unsigned, 8> LoopLiveIns;
- for (MachineBasicBlock::livein_iterator LI = Header->livein_begin(),
- LE = Header->livein_end(); LI != LE; ++LI)
- LoopLiveIns.insert(*LI);
-
- const MachineDomTreeNode *Node = MDT.getNode(Header);
- const MachineBasicBlock *MBB = Node->getBlock();
- assert(Loop->contains(MBB) &&
- "Loop does not contain header!");
- VisitRegion(Node, MBB, Loop, LoopLiveIns);
- }
-
- private:
- void VisitRegion(const MachineDomTreeNode *Node,
- const MachineBasicBlock *MBB,
- const MachineLoop *Loop,
- const SmallSet<unsigned, 8> &LoopLiveIns) {
- unsigned Count = 0;
- for (MachineBasicBlock::const_iterator I = MBB->begin(), E = MBB->end();
- I != E; ++I) {
- const MachineInstr *MI = I;
- if (MI->isDebugValue())
- continue;
- for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
- const MachineOperand &MO = MI->getOperand(i);
- if (!MO.isReg() || !MO.isUse())
- continue;
- unsigned MOReg = MO.getReg();
- if (LoopLiveIns.count(MOReg))
- Deps.insert(std::make_pair(MOReg, std::make_pair(&MO, Count)));
- }
- ++Count; // Not every iteration due to dbg_value above.
- }
-
- const std::vector<MachineDomTreeNode*> &Children = Node->getChildren();
- for (std::vector<MachineDomTreeNode*>::const_iterator I =
- Children.begin(), E = Children.end(); I != E; ++I) {
- const MachineDomTreeNode *ChildNode = *I;
- MachineBasicBlock *ChildBlock = ChildNode->getBlock();
- if (Loop->contains(ChildBlock))
- VisitRegion(ChildNode, ChildBlock, Loop, LoopLiveIns);
- }
- }
- };
+ class PressureDiffs;
/// An individual mapping from virtual register number to SUnit.
struct VReg2SUnit {
}
};
- /// Combine a SparseSet with a 1x1 vector to track physical registers.
- /// The SparseSet allows iterating over the (few) live registers for quickly
- /// comparing against a regmask or clearing the set.
- ///
- /// Storage for the map is allocated once for the pass. The map can be
- /// cleared between scheduling regions without freeing unused entries.
- class Reg2SUnitsMap {
- SparseSet<unsigned> PhysRegSet;
- std::vector<std::vector<SUnit*> > SUnits;
- public:
- typedef SparseSet<unsigned>::const_iterator const_iterator;
-
- // Allow iteration over register numbers (keys) in the map. If needed, we
- // can provide an iterator over SUnits (values) as well.
- const_iterator reg_begin() const { return PhysRegSet.begin(); }
- const_iterator reg_end() const { return PhysRegSet.end(); }
-
- /// Initialize the map with the number of registers.
- /// If the map is already large enough, no allocation occurs.
- /// For simplicity we expect the map to be empty().
- void setRegLimit(unsigned Limit);
-
- /// Returns true if the map is empty.
- bool empty() const { return PhysRegSet.empty(); }
-
- /// Clear the map without deallocating storage.
- void clear();
-
- bool contains(unsigned Reg) const { return PhysRegSet.count(Reg); }
+ /// Record a physical register access.
+ /// For non-data-dependent uses, OpIdx == -1.
+ struct PhysRegSUOper {
+ SUnit *SU;
+ int OpIdx;
+ unsigned Reg;
- /// If this register is mapped, return its existing SUnits vector.
- /// Otherwise map the register and return an empty SUnits vector.
- std::vector<SUnit *> &operator[](unsigned Reg) {
- bool New = PhysRegSet.insert(Reg).second;
- assert((!New || SUnits[Reg].empty()) && "stale SUnits vector");
- (void)New;
- return SUnits[Reg];
- }
+ PhysRegSUOper(SUnit *su, int op, unsigned R): SU(su), OpIdx(op), Reg(R) {}
- /// Erase an existing element without freeing memory.
- void erase(unsigned Reg) {
- PhysRegSet.erase(Reg);
- SUnits[Reg].clear();
- }
+ unsigned getSparseSetIndex() const { return Reg; }
};
+ /// Use a SparseMultiSet to track physical registers. Storage is only
+ /// allocated once for the pass. It can be cleared in constant time and reused
+ /// without any frees.
+ typedef SparseMultiSet<PhysRegSUOper, llvm::identity<unsigned>, uint16_t>
+ Reg2SUnitsMap;
+
/// Use SparseSet as a SparseMap by relying on the fact that it never
/// compares ValueT's, only unsigned keys. This allows the set to be cleared
/// between scheduling regions in constant time as long as ValueT does not
/// require a destructor.
typedef SparseSet<VReg2SUnit, VirtReg2IndexFunctor> VReg2SUnitMap;
+ /// Track local uses of virtual registers. These uses are gathered by the DAG
+ /// builder and may be consulted by the scheduler to avoid iterating an entire
+ /// vreg use list.
+ typedef SparseMultiSet<VReg2SUnit, VirtReg2IndexFunctor> VReg2UseMap;
+
/// ScheduleDAGInstrs - A ScheduleDAG subclass for scheduling lists of
/// MachineInstrs.
class ScheduleDAGInstrs : public ScheduleDAG {
protected:
- const MachineLoopInfo &MLI;
- const MachineDominatorTree &MDT;
+ const MachineLoopInfo *MLI;
const MachineFrameInfo *MFI;
- const InstrItineraryData *InstrItins;
/// Live Intervals provides reaching defs in preRA scheduling.
LiveIntervals *LIS;
+ /// TargetSchedModel provides an interface to the machine model.
+ TargetSchedModel SchedModel;
+
/// isPostRA flag indicates vregs cannot be present.
bool IsPostRA;
- /// UnitLatencies (misnamed) flag avoids computing def-use latencies, using
- /// the def-side latency only.
- bool UnitLatencies;
+ /// True if the DAG builder should remove kill flags (in preparation for
+ /// rescheduling).
+ bool RemoveKillFlags;
/// The standard DAG builder does not normally include terminators as DAG
/// nodes because it does not create the necessary dependencies to prevent
- /// reordering. A specialized scheduler can overide
+ /// reordering. A specialized scheduler can override
/// TargetInstrInfo::isSchedulingBoundary then enable this flag to indicate
/// it has taken responsibility for scheduling the terminator correctly.
bool CanHandleTerminators;
/// The end of the range to be scheduled.
MachineBasicBlock::iterator RegionEnd;
- /// The index in BB of RegionEnd.
- unsigned EndIndex;
+ /// Instructions in this region (distance(RegionBegin, RegionEnd)).
+ unsigned NumRegionInstrs;
/// After calling BuildSchedGraph, each machine instruction in the current
/// scheduling region is mapped to an SUnit.
DenseMap<MachineInstr*, SUnit*> MISUnitMap;
+ /// After calling BuildSchedGraph, each vreg used in the scheduling region
+ /// is mapped to a set of SUnits. These include all local vreg uses, not
+ /// just the uses for a singly defined vreg.
+ VReg2UseMap VRegUses;
+
/// State internal to DAG building.
/// -------------------------------
Reg2SUnitsMap Defs;
Reg2SUnitsMap Uses;
- /// Track the last instructon in this region defining each virtual register.
+ /// Track the last instruction in this region defining each virtual register.
VReg2SUnitMap VRegDefs;
/// PendingLoads - Remember where unknown loads are after the most recent
/// to minimize construction/destruction.
std::vector<SUnit *> PendingLoads;
- /// LoopRegs - Track which registers are used for loop-carried dependencies.
- ///
- LoopDependencies LoopRegs;
-
/// DbgValues - Remember instruction that precedes DBG_VALUE.
/// These are generated by buildSchedGraph but persist so they can be
/// referenced when emitting the final schedule.
DbgValueVector DbgValues;
MachineInstr *FirstDbgValue;
+ /// Set of live physical registers for updating kill flags.
+ BitVector LiveRegs;
+
public:
explicit ScheduleDAGInstrs(MachineFunction &mf,
- const MachineLoopInfo &mli,
- const MachineDominatorTree &mdt,
+ const MachineLoopInfo *mli,
bool IsPostRAFlag,
- LiveIntervals *LIS = 0);
+ bool RemoveKillFlags = false,
+ LiveIntervals *LIS = nullptr);
virtual ~ScheduleDAGInstrs() {}
+ bool isPostRA() const { return IsPostRA; }
+
+ /// \brief Expose LiveIntervals for use in DAG mutators and such.
+ LiveIntervals *getLIS() const { return LIS; }
+
+ /// \brief Get the machine model for instruction scheduling.
+ const TargetSchedModel *getSchedModel() const { return &SchedModel; }
+
+ /// \brief Resolve and cache a resolved scheduling class for an SUnit.
+ const MCSchedClassDesc *getSchedClass(SUnit *SU) const {
+ if (!SU->SchedClass && SchedModel.hasInstrSchedModel())
+ SU->SchedClass = SchedModel.resolveSchedClass(SU->getInstr());
+ return SU->SchedClass;
+ }
+
/// begin - Return an iterator to the top of the current scheduling region.
MachineBasicBlock::iterator begin() const { return RegionBegin; }
virtual void enterRegion(MachineBasicBlock *bb,
MachineBasicBlock::iterator begin,
MachineBasicBlock::iterator end,
- unsigned endcount);
+ unsigned regioninstrs);
/// Notify that the scheduler has finished scheduling the current region.
virtual void exitRegion();
/// buildSchedGraph - Build SUnits from the MachineBasicBlock that we are
/// input.
- void buildSchedGraph(AliasAnalysis *AA, RegPressureTracker *RPTracker = 0);
+ void buildSchedGraph(AliasAnalysis *AA,
+ RegPressureTracker *RPTracker = nullptr,
+ PressureDiffs *PDiffs = nullptr);
/// addSchedBarrierDeps - Add dependencies from instructions in the current
/// list of instructions being scheduled to scheduling barrier. We want to
/// used by instructions in the fallthrough block.
void addSchedBarrierDeps();
- /// computeLatency - Compute node latency.
- ///
- virtual void computeLatency(SUnit *SU);
-
- /// computeOperandLatency - Return dependence edge latency using
- /// operand use/def information
- ///
- /// FindMin may be set to get the minimum vs. expected latency. Minimum
- /// latency is used for scheduling groups, while expected latency is for
- /// instruction cost and critical path.
- virtual unsigned computeOperandLatency(SUnit *Def, SUnit *Use,
- const SDep& dep,
- bool FindMin = false) const;
-
/// schedule - Order nodes according to selected style, filling
/// in the Sequence member.
///
/// the level of the whole MachineFunction. By default does nothing.
virtual void finalizeSchedule() {}
- virtual void dumpNode(const SUnit *SU) const;
+ void dumpNode(const SUnit *SU) const override;
/// Return a label for a DAG node that points to an instruction.
- virtual std::string getGraphNodeLabel(const SUnit *SU) const;
+ std::string getGraphNodeLabel(const SUnit *SU) const override;
/// Return a label for the region of code covered by the DAG.
- virtual std::string getDAGName() const;
+ std::string getDAGName() const override;
+ /// \brief Fix register kill flags that scheduling has made invalid.
+ void fixupKills(MachineBasicBlock *MBB);
protected:
void initSUnits();
- void addPhysRegDataDeps(SUnit *SU, const MachineOperand &MO);
+ void addPhysRegDataDeps(SUnit *SU, unsigned OperIdx);
void addPhysRegDeps(SUnit *SU, unsigned OperIdx);
void addVRegDefDeps(SUnit *SU, unsigned OperIdx);
void addVRegUseDeps(SUnit *SU, unsigned OperIdx);
+
+ /// \brief PostRA helper for rewriting kill flags.
+ void startBlockForKills(MachineBasicBlock *BB);
+
+ /// \brief Toggle a register operand kill flag.
+ ///
+ /// Other adjustments may be made to the instruction if necessary. Return
+ /// true if the operand has been deleted, false if not.
+ bool toggleKillFlag(MachineInstr *MI, MachineOperand &MO);
};
/// newSUnit - Creates a new SUnit and return a ptr to it.
inline SUnit *ScheduleDAGInstrs::newSUnit(MachineInstr *MI) {
#ifndef NDEBUG
- const SUnit *Addr = SUnits.empty() ? 0 : &SUnits[0];
+ const SUnit *Addr = SUnits.empty() ? nullptr : &SUnits[0];
#endif
SUnits.push_back(SUnit(MI, (unsigned)SUnits.size()));
- assert((Addr == 0 || Addr == &SUnits[0]) &&
+ assert((Addr == nullptr || Addr == &SUnits[0]) &&
"SUnits std::vector reallocated on the fly!");
SUnits.back().OrigNode = &SUnits.back();
return &SUnits.back();
inline SUnit *ScheduleDAGInstrs::getSUnit(MachineInstr *MI) const {
DenseMap<MachineInstr*, SUnit*>::const_iterator I = MISUnitMap.find(MI);
if (I == MISUnitMap.end())
- return 0;
+ return nullptr;
return I->second;
}
} // namespace llvm