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authorLama Saba <lama.saba@intel.com>2019-01-08 13:30:36 +0000
committerLama Saba <lama.saba@intel.com>2019-01-08 13:30:36 +0000
commit32f08399eb298519bf0bffc36ca9eb24b20b33d6 (patch)
treee3c5f635d8bf30b50d19f824841e5b873ae64377 /llvm/lib/CodeGen/MachinePipeliner.cpp
parent964eea7ad2041d193e51ef606ecb2a4d2b8e7b7f (diff)
downloadbcm5719-llvm-32f08399eb298519bf0bffc36ca9eb24b20b33d6.tar.gz
bcm5719-llvm-32f08399eb298519bf0bffc36ca9eb24b20b33d6.zip
Revert "Revert "Resubmit rL345008 "Split MachinePipeliner code into header and cpp files"""
This reverts commit rL350497 reported remaining issues seem to be unrelated to modules or this change. more info: https://reviews.llvm.org/D56084 llvm-svn: 350621
Diffstat (limited to 'llvm/lib/CodeGen/MachinePipeliner.cpp')
-rw-r--r--llvm/lib/CodeGen/MachinePipeliner.cpp600
1 files changed, 5 insertions, 595 deletions
diff --git a/llvm/lib/CodeGen/MachinePipeliner.cpp b/llvm/lib/CodeGen/MachinePipeliner.cpp
index de8c55585d3..845cdc4abc9 100644
--- a/llvm/lib/CodeGen/MachinePipeliner.cpp
+++ b/llvm/lib/CodeGen/MachinePipeliner.cpp
@@ -9,34 +9,6 @@
//
// An implementation of the Swing Modulo Scheduling (SMS) software pipeliner.
//
-// Software pipelining (SWP) is an instruction scheduling technique for loops
-// that overlap loop iterations and exploits ILP via a compiler transformation.
-//
-// Swing Modulo Scheduling is an implementation of software pipelining
-// that generates schedules that are near optimal in terms of initiation
-// interval, register requirements, and stage count. See the papers:
-//
-// "Swing Modulo Scheduling: A Lifetime-Sensitive Approach", by J. Llosa,
-// A. Gonzalez, E. Ayguade, and M. Valero. In PACT '96 Proceedings of the 1996
-// Conference on Parallel Architectures and Compilation Techiniques.
-//
-// "Lifetime-Sensitive Modulo Scheduling in a Production Environment", by J.
-// Llosa, E. Ayguade, A. Gonzalez, M. Valero, and J. Eckhardt. In IEEE
-// Transactions on Computers, Vol. 50, No. 3, 2001.
-//
-// "An Implementation of Swing Modulo Scheduling With Extensions for
-// Superblocks", by T. Lattner, Master's Thesis, University of Illinois at
-// Urbana-Chambpain, 2005.
-//
-//
-// The SMS algorithm consists of three main steps after computing the minimal
-// initiation interval (MII).
-// 1) Analyze the dependence graph and compute information about each
-// instruction in the graph.
-// 2) Order the nodes (instructions) by priority based upon the heuristics
-// described in the algorithm.
-// 3) Attempt to schedule the nodes in the specified order using the MII.
-//
// This SMS implementation is a target-independent back-end pass. When enabled,
// the pass runs just prior to the register allocation pass, while the machine
// IR is in SSA form. If software pipelining is successful, then the original
@@ -83,13 +55,11 @@
#include "llvm/CodeGen/MachineLoopInfo.h"
#include "llvm/CodeGen/MachineMemOperand.h"
#include "llvm/CodeGen/MachineOperand.h"
+#include "llvm/CodeGen/MachinePipeliner.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/CodeGen/RegisterClassInfo.h"
#include "llvm/CodeGen/RegisterPressure.h"
#include "llvm/CodeGen/ScheduleDAG.h"
-#include "llvm/CodeGen/ScheduleDAGInstrs.h"
#include "llvm/CodeGen/ScheduleDAGMutation.h"
-#include "llvm/CodeGen/TargetInstrInfo.h"
#include "llvm/CodeGen/TargetOpcodes.h"
#include "llvm/CodeGen/TargetRegisterInfo.h"
#include "llvm/CodeGen/TargetSubtargetInfo.h"
@@ -171,575 +141,15 @@ static cl::opt<bool> SwpIgnoreRecMII("pipeliner-ignore-recmii",
cl::ReallyHidden, cl::init(false),
cl::ZeroOrMore, cl::desc("Ignore RecMII"));
+namespace llvm {
+
// A command line option to enable the CopyToPhi DAG mutation.
-static cl::opt<bool>
+cl::opt<bool>
SwpEnableCopyToPhi("pipeliner-enable-copytophi", cl::ReallyHidden,
cl::init(true), cl::ZeroOrMore,
cl::desc("Enable CopyToPhi DAG Mutation"));
-namespace {
-
-class NodeSet;
-class SMSchedule;
-
-/// The main class in the implementation of the target independent
-/// software pipeliner pass.
-class MachinePipeliner : public MachineFunctionPass {
-public:
- MachineFunction *MF = nullptr;
- const MachineLoopInfo *MLI = nullptr;
- const MachineDominatorTree *MDT = nullptr;
- const InstrItineraryData *InstrItins;
- const TargetInstrInfo *TII = nullptr;
- RegisterClassInfo RegClassInfo;
-
-#ifndef NDEBUG
- static int NumTries;
-#endif
-
- /// Cache the target analysis information about the loop.
- struct LoopInfo {
- MachineBasicBlock *TBB = nullptr;
- MachineBasicBlock *FBB = nullptr;
- SmallVector<MachineOperand, 4> BrCond;
- MachineInstr *LoopInductionVar = nullptr;
- MachineInstr *LoopCompare = nullptr;
- };
- LoopInfo LI;
-
- static char ID;
-
- MachinePipeliner() : MachineFunctionPass(ID) {
- initializeMachinePipelinerPass(*PassRegistry::getPassRegistry());
- }
-
- bool runOnMachineFunction(MachineFunction &MF) override;
-
- void getAnalysisUsage(AnalysisUsage &AU) const override {
- AU.addRequired<AAResultsWrapperPass>();
- AU.addPreserved<AAResultsWrapperPass>();
- AU.addRequired<MachineLoopInfo>();
- AU.addRequired<MachineDominatorTree>();
- AU.addRequired<LiveIntervals>();
- MachineFunctionPass::getAnalysisUsage(AU);
- }
-
-private:
- void preprocessPhiNodes(MachineBasicBlock &B);
- bool canPipelineLoop(MachineLoop &L);
- bool scheduleLoop(MachineLoop &L);
- bool swingModuloScheduler(MachineLoop &L);
-};
-
-/// This class builds the dependence graph for the instructions in a loop,
-/// and attempts to schedule the instructions using the SMS algorithm.
-class SwingSchedulerDAG : public ScheduleDAGInstrs {
- MachinePipeliner &Pass;
- /// The minimum initiation interval between iterations for this schedule.
- unsigned MII = 0;
- /// Set to true if a valid pipelined schedule is found for the loop.
- bool Scheduled = false;
- MachineLoop &Loop;
- LiveIntervals &LIS;
- const RegisterClassInfo &RegClassInfo;
-
- /// A toplogical ordering of the SUnits, which is needed for changing
- /// dependences and iterating over the SUnits.
- ScheduleDAGTopologicalSort Topo;
-
- struct NodeInfo {
- int ASAP = 0;
- int ALAP = 0;
- int ZeroLatencyDepth = 0;
- int ZeroLatencyHeight = 0;
-
- NodeInfo() = default;
- };
- /// Computed properties for each node in the graph.
- std::vector<NodeInfo> ScheduleInfo;
-
- enum OrderKind { BottomUp = 0, TopDown = 1 };
- /// Computed node ordering for scheduling.
- SetVector<SUnit *> NodeOrder;
-
- using NodeSetType = SmallVector<NodeSet, 8>;
- using ValueMapTy = DenseMap<unsigned, unsigned>;
- using MBBVectorTy = SmallVectorImpl<MachineBasicBlock *>;
- using InstrMapTy = DenseMap<MachineInstr *, MachineInstr *>;
-
- /// Instructions to change when emitting the final schedule.
- DenseMap<SUnit *, std::pair<unsigned, int64_t>> InstrChanges;
-
- /// We may create a new instruction, so remember it because it
- /// must be deleted when the pass is finished.
- SmallPtrSet<MachineInstr *, 4> NewMIs;
-
- /// Ordered list of DAG postprocessing steps.
- std::vector<std::unique_ptr<ScheduleDAGMutation>> Mutations;
-
- /// Helper class to implement Johnson's circuit finding algorithm.
- class Circuits {
- std::vector<SUnit> &SUnits;
- SetVector<SUnit *> Stack;
- BitVector Blocked;
- SmallVector<SmallPtrSet<SUnit *, 4>, 10> B;
- SmallVector<SmallVector<int, 4>, 16> AdjK;
- // Node to Index from ScheduleDAGTopologicalSort
- std::vector<int> *Node2Idx;
- unsigned NumPaths;
- static unsigned MaxPaths;
-
- public:
- Circuits(std::vector<SUnit> &SUs, ScheduleDAGTopologicalSort &Topo)
- : SUnits(SUs), Blocked(SUs.size()), B(SUs.size()), AdjK(SUs.size()) {
- Node2Idx = new std::vector<int>(SUs.size());
- unsigned Idx = 0;
- for (const auto &NodeNum : Topo)
- Node2Idx->at(NodeNum) = Idx++;
- }
-
- ~Circuits() { delete Node2Idx; }
-
- /// Reset the data structures used in the circuit algorithm.
- void reset() {
- Stack.clear();
- Blocked.reset();
- B.assign(SUnits.size(), SmallPtrSet<SUnit *, 4>());
- NumPaths = 0;
- }
-
- void createAdjacencyStructure(SwingSchedulerDAG *DAG);
- bool circuit(int V, int S, NodeSetType &NodeSets, bool HasBackedge = false);
- void unblock(int U);
- };
-
- struct CopyToPhiMutation : public ScheduleDAGMutation {
- void apply(ScheduleDAGInstrs *DAG) override;
- };
-
-public:
- SwingSchedulerDAG(MachinePipeliner &P, MachineLoop &L, LiveIntervals &lis,
- const RegisterClassInfo &rci)
- : ScheduleDAGInstrs(*P.MF, P.MLI, false), Pass(P), Loop(L), LIS(lis),
- RegClassInfo(rci), Topo(SUnits, &ExitSU) {
- P.MF->getSubtarget().getSMSMutations(Mutations);
- if (SwpEnableCopyToPhi)
- Mutations.push_back(llvm::make_unique<CopyToPhiMutation>());
- }
-
- void schedule() override;
- void finishBlock() override;
-
- /// Return true if the loop kernel has been scheduled.
- bool hasNewSchedule() { return Scheduled; }
-
- /// Return the earliest time an instruction may be scheduled.
- int getASAP(SUnit *Node) { return ScheduleInfo[Node->NodeNum].ASAP; }
-
- /// Return the latest time an instruction my be scheduled.
- int getALAP(SUnit *Node) { return ScheduleInfo[Node->NodeNum].ALAP; }
-
- /// The mobility function, which the number of slots in which
- /// an instruction may be scheduled.
- int getMOV(SUnit *Node) { return getALAP(Node) - getASAP(Node); }
-
- /// The depth, in the dependence graph, for a node.
- unsigned getDepth(SUnit *Node) { return Node->getDepth(); }
-
- /// The maximum unweighted length of a path from an arbitrary node to the
- /// given node in which each edge has latency 0
- int getZeroLatencyDepth(SUnit *Node) {
- return ScheduleInfo[Node->NodeNum].ZeroLatencyDepth;
- }
-
- /// The height, in the dependence graph, for a node.
- unsigned getHeight(SUnit *Node) { return Node->getHeight(); }
-
- /// The maximum unweighted length of a path from the given node to an
- /// arbitrary node in which each edge has latency 0
- int getZeroLatencyHeight(SUnit *Node) {
- return ScheduleInfo[Node->NodeNum].ZeroLatencyHeight;
- }
-
- /// Return true if the dependence is a back-edge in the data dependence graph.
- /// Since the DAG doesn't contain cycles, we represent a cycle in the graph
- /// using an anti dependence from a Phi to an instruction.
- bool isBackedge(SUnit *Source, const SDep &Dep) {
- if (Dep.getKind() != SDep::Anti)
- return false;
- return Source->getInstr()->isPHI() || Dep.getSUnit()->getInstr()->isPHI();
- }
-
- bool isLoopCarriedDep(SUnit *Source, const SDep &Dep, bool isSucc = true);
-
- /// The distance function, which indicates that operation V of iteration I
- /// depends on operations U of iteration I-distance.
- unsigned getDistance(SUnit *U, SUnit *V, const SDep &Dep) {
- // Instructions that feed a Phi have a distance of 1. Computing larger
- // values for arrays requires data dependence information.
- if (V->getInstr()->isPHI() && Dep.getKind() == SDep::Anti)
- return 1;
- return 0;
- }
-
- /// Set the Minimum Initiation Interval for this schedule attempt.
- void setMII(unsigned mii) { MII = mii; }
-
- void applyInstrChange(MachineInstr *MI, SMSchedule &Schedule);
-
- void fixupRegisterOverlaps(std::deque<SUnit *> &Instrs);
-
- /// Return the new base register that was stored away for the changed
- /// instruction.
- unsigned getInstrBaseReg(SUnit *SU) {
- DenseMap<SUnit *, std::pair<unsigned, int64_t>>::iterator It =
- InstrChanges.find(SU);
- if (It != InstrChanges.end())
- return It->second.first;
- return 0;
- }
-
- void addMutation(std::unique_ptr<ScheduleDAGMutation> Mutation) {
- Mutations.push_back(std::move(Mutation));
- }
-
- static bool classof(const ScheduleDAGInstrs *DAG) { return true; }
-
-private:
- void addLoopCarriedDependences(AliasAnalysis *AA);
- void updatePhiDependences();
- void changeDependences();
- unsigned calculateResMII();
- unsigned calculateRecMII(NodeSetType &RecNodeSets);
- void findCircuits(NodeSetType &NodeSets);
- void fuseRecs(NodeSetType &NodeSets);
- void removeDuplicateNodes(NodeSetType &NodeSets);
- void computeNodeFunctions(NodeSetType &NodeSets);
- void registerPressureFilter(NodeSetType &NodeSets);
- void colocateNodeSets(NodeSetType &NodeSets);
- void checkNodeSets(NodeSetType &NodeSets);
- void groupRemainingNodes(NodeSetType &NodeSets);
- void addConnectedNodes(SUnit *SU, NodeSet &NewSet,
- SetVector<SUnit *> &NodesAdded);
- void computeNodeOrder(NodeSetType &NodeSets);
- void checkValidNodeOrder(const NodeSetType &Circuits) const;
- bool schedulePipeline(SMSchedule &Schedule);
- void generatePipelinedLoop(SMSchedule &Schedule);
- void generateProlog(SMSchedule &Schedule, unsigned LastStage,
- MachineBasicBlock *KernelBB, ValueMapTy *VRMap,
- MBBVectorTy &PrologBBs);
- void generateEpilog(SMSchedule &Schedule, unsigned LastStage,
- MachineBasicBlock *KernelBB, ValueMapTy *VRMap,
- MBBVectorTy &EpilogBBs, MBBVectorTy &PrologBBs);
- void generateExistingPhis(MachineBasicBlock *NewBB, MachineBasicBlock *BB1,
- MachineBasicBlock *BB2, MachineBasicBlock *KernelBB,
- SMSchedule &Schedule, ValueMapTy *VRMap,
- InstrMapTy &InstrMap, unsigned LastStageNum,
- unsigned CurStageNum, bool IsLast);
- void generatePhis(MachineBasicBlock *NewBB, MachineBasicBlock *BB1,
- MachineBasicBlock *BB2, MachineBasicBlock *KernelBB,
- SMSchedule &Schedule, ValueMapTy *VRMap,
- InstrMapTy &InstrMap, unsigned LastStageNum,
- unsigned CurStageNum, bool IsLast);
- void removeDeadInstructions(MachineBasicBlock *KernelBB,
- MBBVectorTy &EpilogBBs);
- void splitLifetimes(MachineBasicBlock *KernelBB, MBBVectorTy &EpilogBBs,
- SMSchedule &Schedule);
- void addBranches(MBBVectorTy &PrologBBs, MachineBasicBlock *KernelBB,
- MBBVectorTy &EpilogBBs, SMSchedule &Schedule,
- ValueMapTy *VRMap);
- bool computeDelta(MachineInstr &MI, unsigned &Delta);
- void updateMemOperands(MachineInstr &NewMI, MachineInstr &OldMI,
- unsigned Num);
- MachineInstr *cloneInstr(MachineInstr *OldMI, unsigned CurStageNum,
- unsigned InstStageNum);
- MachineInstr *cloneAndChangeInstr(MachineInstr *OldMI, unsigned CurStageNum,
- unsigned InstStageNum,
- SMSchedule &Schedule);
- void updateInstruction(MachineInstr *NewMI, bool LastDef,
- unsigned CurStageNum, unsigned InstrStageNum,
- SMSchedule &Schedule, ValueMapTy *VRMap);
- MachineInstr *findDefInLoop(unsigned Reg);
- unsigned getPrevMapVal(unsigned StageNum, unsigned PhiStage, unsigned LoopVal,
- unsigned LoopStage, ValueMapTy *VRMap,
- MachineBasicBlock *BB);
- void rewritePhiValues(MachineBasicBlock *NewBB, unsigned StageNum,
- SMSchedule &Schedule, ValueMapTy *VRMap,
- InstrMapTy &InstrMap);
- void rewriteScheduledInstr(MachineBasicBlock *BB, SMSchedule &Schedule,
- InstrMapTy &InstrMap, unsigned CurStageNum,
- unsigned PhiNum, MachineInstr *Phi,
- unsigned OldReg, unsigned NewReg,
- unsigned PrevReg = 0);
- bool canUseLastOffsetValue(MachineInstr *MI, unsigned &BasePos,
- unsigned &OffsetPos, unsigned &NewBase,
- int64_t &NewOffset);
- void postprocessDAG();
-};
-
-/// A NodeSet contains a set of SUnit DAG nodes with additional information
-/// that assigns a priority to the set.
-class NodeSet {
- SetVector<SUnit *> Nodes;
- bool HasRecurrence = false;
- unsigned RecMII = 0;
- int MaxMOV = 0;
- unsigned MaxDepth = 0;
- unsigned Colocate = 0;
- SUnit *ExceedPressure = nullptr;
- unsigned Latency = 0;
-
-public:
- using iterator = SetVector<SUnit *>::const_iterator;
-
- NodeSet() = default;
- NodeSet(iterator S, iterator E) : Nodes(S, E), HasRecurrence(true) {
- Latency = 0;
- for (unsigned i = 0, e = Nodes.size(); i < e; ++i)
- for (const SDep &Succ : Nodes[i]->Succs)
- if (Nodes.count(Succ.getSUnit()))
- Latency += Succ.getLatency();
- }
-
- bool insert(SUnit *SU) { return Nodes.insert(SU); }
-
- void insert(iterator S, iterator E) { Nodes.insert(S, E); }
-
- template <typename UnaryPredicate> bool remove_if(UnaryPredicate P) {
- return Nodes.remove_if(P);
- }
-
- unsigned count(SUnit *SU) const { return Nodes.count(SU); }
-
- bool hasRecurrence() { return HasRecurrence; };
-
- unsigned size() const { return Nodes.size(); }
-
- bool empty() const { return Nodes.empty(); }
-
- SUnit *getNode(unsigned i) const { return Nodes[i]; };
-
- void setRecMII(unsigned mii) { RecMII = mii; };
-
- void setColocate(unsigned c) { Colocate = c; };
-
- void setExceedPressure(SUnit *SU) { ExceedPressure = SU; }
-
- bool isExceedSU(SUnit *SU) { return ExceedPressure == SU; }
-
- int compareRecMII(NodeSet &RHS) { return RecMII - RHS.RecMII; }
-
- int getRecMII() { return RecMII; }
-
- /// Summarize node functions for the entire node set.
- void computeNodeSetInfo(SwingSchedulerDAG *SSD) {
- for (SUnit *SU : *this) {
- MaxMOV = std::max(MaxMOV, SSD->getMOV(SU));
- MaxDepth = std::max(MaxDepth, SSD->getDepth(SU));
- }
- }
-
- unsigned getLatency() { return Latency; }
-
- unsigned getMaxDepth() { return MaxDepth; }
-
- void clear() {
- Nodes.clear();
- RecMII = 0;
- HasRecurrence = false;
- MaxMOV = 0;
- MaxDepth = 0;
- Colocate = 0;
- ExceedPressure = nullptr;
- }
-
- operator SetVector<SUnit *> &() { return Nodes; }
-
- /// Sort the node sets by importance. First, rank them by recurrence MII,
- /// then by mobility (least mobile done first), and finally by depth.
- /// Each node set may contain a colocate value which is used as the first
- /// tie breaker, if it's set.
- bool operator>(const NodeSet &RHS) const {
- if (RecMII == RHS.RecMII) {
- if (Colocate != 0 && RHS.Colocate != 0 && Colocate != RHS.Colocate)
- return Colocate < RHS.Colocate;
- if (MaxMOV == RHS.MaxMOV)
- return MaxDepth > RHS.MaxDepth;
- return MaxMOV < RHS.MaxMOV;
- }
- return RecMII > RHS.RecMII;
- }
-
- bool operator==(const NodeSet &RHS) const {
- return RecMII == RHS.RecMII && MaxMOV == RHS.MaxMOV &&
- MaxDepth == RHS.MaxDepth;
- }
-
- bool operator!=(const NodeSet &RHS) const { return !operator==(RHS); }
-
- iterator begin() { return Nodes.begin(); }
- iterator end() { return Nodes.end(); }
-
- void print(raw_ostream &os) const {
- os << "Num nodes " << size() << " rec " << RecMII << " mov " << MaxMOV
- << " depth " << MaxDepth << " col " << Colocate << "\n";
- for (const auto &I : Nodes)
- os << " SU(" << I->NodeNum << ") " << *(I->getInstr());
- os << "\n";
- }
-
-#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
- LLVM_DUMP_METHOD void dump() const { print(dbgs()); }
-#endif
-};
-
-/// This class represents the scheduled code. The main data structure is a
-/// map from scheduled cycle to instructions. During scheduling, the
-/// data structure explicitly represents all stages/iterations. When
-/// the algorithm finshes, the schedule is collapsed into a single stage,
-/// which represents instructions from different loop iterations.
-///
-/// The SMS algorithm allows negative values for cycles, so the first cycle
-/// in the schedule is the smallest cycle value.
-class SMSchedule {
-private:
- /// Map from execution cycle to instructions.
- DenseMap<int, std::deque<SUnit *>> ScheduledInstrs;
-
- /// Map from instruction to execution cycle.
- std::map<SUnit *, int> InstrToCycle;
-
- /// Map for each register and the max difference between its uses and def.
- /// The first element in the pair is the max difference in stages. The
- /// second is true if the register defines a Phi value and loop value is
- /// scheduled before the Phi.
- std::map<unsigned, std::pair<unsigned, bool>> RegToStageDiff;
-
- /// Keep track of the first cycle value in the schedule. It starts
- /// as zero, but the algorithm allows negative values.
- int FirstCycle = 0;
-
- /// Keep track of the last cycle value in the schedule.
- int LastCycle = 0;
-
- /// The initiation interval (II) for the schedule.
- int InitiationInterval = 0;
-
- /// Target machine information.
- const TargetSubtargetInfo &ST;
-
- /// Virtual register information.
- MachineRegisterInfo &MRI;
-
- std::unique_ptr<DFAPacketizer> Resources;
-
-public:
- SMSchedule(MachineFunction *mf)
- : ST(mf->getSubtarget()), MRI(mf->getRegInfo()),
- Resources(ST.getInstrInfo()->CreateTargetScheduleState(ST)) {}
-
- void reset() {
- ScheduledInstrs.clear();
- InstrToCycle.clear();
- RegToStageDiff.clear();
- FirstCycle = 0;
- LastCycle = 0;
- InitiationInterval = 0;
- }
-
- /// Set the initiation interval for this schedule.
- void setInitiationInterval(int ii) { InitiationInterval = ii; }
-
- /// Return the first cycle in the completed schedule. This
- /// can be a negative value.
- int getFirstCycle() const { return FirstCycle; }
-
- /// Return the last cycle in the finalized schedule.
- int getFinalCycle() const { return FirstCycle + InitiationInterval - 1; }
-
- /// Return the cycle of the earliest scheduled instruction in the dependence
- /// chain.
- int earliestCycleInChain(const SDep &Dep);
-
- /// Return the cycle of the latest scheduled instruction in the dependence
- /// chain.
- int latestCycleInChain(const SDep &Dep);
-
- void computeStart(SUnit *SU, int *MaxEarlyStart, int *MinLateStart,
- int *MinEnd, int *MaxStart, int II, SwingSchedulerDAG *DAG);
- bool insert(SUnit *SU, int StartCycle, int EndCycle, int II);
-
- /// Iterators for the cycle to instruction map.
- using sched_iterator = DenseMap<int, std::deque<SUnit *>>::iterator;
- using const_sched_iterator =
- DenseMap<int, std::deque<SUnit *>>::const_iterator;
-
- /// Return true if the instruction is scheduled at the specified stage.
- bool isScheduledAtStage(SUnit *SU, unsigned StageNum) {
- return (stageScheduled(SU) == (int)StageNum);
- }
-
- /// Return the stage for a scheduled instruction. Return -1 if
- /// the instruction has not been scheduled.
- int stageScheduled(SUnit *SU) const {
- std::map<SUnit *, int>::const_iterator it = InstrToCycle.find(SU);
- if (it == InstrToCycle.end())
- return -1;
- return (it->second - FirstCycle) / InitiationInterval;
- }
-
- /// Return the cycle for a scheduled instruction. This function normalizes
- /// the first cycle to be 0.
- unsigned cycleScheduled(SUnit *SU) const {
- std::map<SUnit *, int>::const_iterator it = InstrToCycle.find(SU);
- assert(it != InstrToCycle.end() && "Instruction hasn't been scheduled.");
- return (it->second - FirstCycle) % InitiationInterval;
- }
-
- /// Return the maximum stage count needed for this schedule.
- unsigned getMaxStageCount() {
- return (LastCycle - FirstCycle) / InitiationInterval;
- }
-
- /// Return the max. number of stages/iterations that can occur between a
- /// register definition and its uses.
- unsigned getStagesForReg(int Reg, unsigned CurStage) {
- std::pair<unsigned, bool> Stages = RegToStageDiff[Reg];
- if (CurStage > getMaxStageCount() && Stages.first == 0 && Stages.second)
- return 1;
- return Stages.first;
- }
-
- /// The number of stages for a Phi is a little different than other
- /// instructions. The minimum value computed in RegToStageDiff is 1
- /// because we assume the Phi is needed for at least 1 iteration.
- /// This is not the case if the loop value is scheduled prior to the
- /// Phi in the same stage. This function returns the number of stages
- /// or iterations needed between the Phi definition and any uses.
- unsigned getStagesForPhi(int Reg) {
- std::pair<unsigned, bool> Stages = RegToStageDiff[Reg];
- if (Stages.second)
- return Stages.first;
- return Stages.first - 1;
- }
-
- /// Return the instructions that are scheduled at the specified cycle.
- std::deque<SUnit *> &getInstructions(int cycle) {
- return ScheduledInstrs[cycle];
- }
-
- bool isValidSchedule(SwingSchedulerDAG *SSD);
- void finalizeSchedule(SwingSchedulerDAG *SSD);
- void orderDependence(SwingSchedulerDAG *SSD, SUnit *SU,
- std::deque<SUnit *> &Insts);
- bool isLoopCarried(SwingSchedulerDAG *SSD, MachineInstr &Phi);
- bool isLoopCarriedDefOfUse(SwingSchedulerDAG *SSD, MachineInstr *Def,
- MachineOperand &MO);
- void print(raw_ostream &os) const;
- void dump() const;
-};
-
-} // end anonymous namespace
+} // end namespace llvm
unsigned SwingSchedulerDAG::Circuits::MaxPaths = 5;
char MachinePipeliner::ID = 0;
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