From c80e1dc081fdb45a6be0ea5fb0b7be012d82865f Mon Sep 17 00:00:00 2001 From: Erik Eckstein Date: Fri, 1 Aug 2014 09:20:42 +0000 Subject: [PATCH] SLPVectorizer: improved scheduling algorithm. llvm-svn: 214494 --- llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp | 942 +++++++++++++++------ .../SLPVectorizer/X86/crash_vectorizeTree.ll | 2 +- .../Transforms/SLPVectorizer/X86/in-tree-user.ll | 9 +- .../Transforms/SLPVectorizer/X86/scheduling.ll | 78 ++ 4 files changed, 778 insertions(+), 253 deletions(-) create mode 100644 llvm/test/Transforms/SLPVectorizer/X86/scheduling.ll diff --git a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp index 9d64e5a..a9e6ffe 100644 --- a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp +++ b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp @@ -43,6 +43,7 @@ #include "llvm/Transforms/Utils/VectorUtils.h" #include #include +#include using namespace llvm; @@ -71,53 +72,6 @@ static const unsigned MinVecRegSize = 128; static const unsigned RecursionMaxDepth = 12; -/// A helper class for numbering instructions in multiple blocks. -/// Numbers start at zero for each basic block. -struct BlockNumbering { - - BlockNumbering(BasicBlock *Bb) : BB(Bb), Valid(false) {} - - void numberInstructions() { - unsigned Loc = 0; - InstrIdx.clear(); - InstrVec.clear(); - // Number the instructions in the block. - for (BasicBlock::iterator it = BB->begin(), e = BB->end(); it != e; ++it) { - InstrIdx[it] = Loc++; - InstrVec.push_back(it); - assert(InstrVec[InstrIdx[it]] == it && "Invalid allocation"); - } - Valid = true; - } - - int getIndex(Instruction *I) { - assert(I->getParent() == BB && "Invalid instruction"); - if (!Valid) - numberInstructions(); - assert(InstrIdx.count(I) && "Unknown instruction"); - return InstrIdx[I]; - } - - Instruction *getInstruction(unsigned loc) { - if (!Valid) - numberInstructions(); - assert(InstrVec.size() > loc && "Invalid Index"); - return InstrVec[loc]; - } - - void forget() { Valid = false; } - -private: - /// The block we are numbering. - BasicBlock *BB; - /// Is the block numbered. - bool Valid; - /// Maps instructions to numbers and back. - SmallDenseMap InstrIdx; - /// Maps integers to Instructions. - SmallVector InstrVec; -}; - /// \returns the parent basic block if all of the instructions in \p VL /// are in the same block or null otherwise. static BasicBlock *getSameBlock(ArrayRef VL) { @@ -422,9 +376,12 @@ public: ScalarToTreeEntry.clear(); MustGather.clear(); ExternalUses.clear(); - MemBarrierIgnoreList.clear(); NumLoadsWantToKeepOrder = 0; NumLoadsWantToChangeOrder = 0; + for (auto &Iter : BlocksSchedules) { + BlockScheduling *BS = Iter.second.get(); + BS->clear(); + } } /// \returns true if the memory operations A and B are consecutive. @@ -474,20 +431,6 @@ private: /// roots. This method calculates the cost of extracting the values. int getGatherCost(ArrayRef VL); - /// \returns the AA location that is being access by the instruction. - AliasAnalysis::Location getLocation(Instruction *I); - - /// \brief Checks if it is possible to sink an instruction from - /// \p Src to \p Dst. - /// \returns the pointer to the barrier instruction if we can't sink. - Value *getSinkBarrier(Instruction *Src, Instruction *Dst); - - /// \returns the index of the last instruction in the BB from \p VL. - int getLastIndex(ArrayRef VL); - - /// \returns the Instruction in the bundle \p VL. - Instruction *getLastInstruction(ArrayRef VL); - /// \brief Set the Builder insert point to one after the last instruction in /// the bundle void setInsertPointAfterBundle(ArrayRef VL); @@ -500,7 +443,7 @@ private: bool isFullyVectorizableTinyTree(); struct TreeEntry { - TreeEntry() : Scalars(), VectorizedValue(nullptr), LastScalarIndex(0), + TreeEntry() : Scalars(), VectorizedValue(nullptr), NeedToGather(0) {} /// \returns true if the scalars in VL are equal to this entry. @@ -515,9 +458,6 @@ private: /// The Scalars are vectorized into this value. It is initialized to Null. Value *VectorizedValue; - /// The index in the basic block of the last scalar. - int LastScalarIndex; - /// Do we need to gather this sequence ? bool NeedToGather; }; @@ -530,18 +470,16 @@ private: Last->Scalars.insert(Last->Scalars.begin(), VL.begin(), VL.end()); Last->NeedToGather = !Vectorized; if (Vectorized) { - Last->LastScalarIndex = getLastIndex(VL); for (int i = 0, e = VL.size(); i != e; ++i) { assert(!ScalarToTreeEntry.count(VL[i]) && "Scalar already in tree!"); ScalarToTreeEntry[VL[i]] = idx; } } else { - Last->LastScalarIndex = 0; MustGather.insert(VL.begin(), VL.end()); } return Last; } - + /// -- Vectorization State -- /// Holds all of the tree entries. std::vector VectorizableTree; @@ -569,24 +507,304 @@ private: /// This list holds pairs of (Internal Scalar : External User). UserList ExternalUses; - /// A list of instructions to ignore while sinking - /// memory instructions. This map must be reset between runs of getCost. - ValueSet MemBarrierIgnoreList; - /// Holds all of the instructions that we gathered. SetVector GatherSeq; /// A list of blocks that we are going to CSE. SetVector CSEBlocks; - /// Numbers instructions in different blocks. - DenseMap BlocksNumbers; + /// Contains all scheduling relevant data for an instruction. + /// A ScheduleData either represents a single instruction or a member of an + /// instruction bundle (= a group of instructions which is combined into a + /// vector instruction). + struct ScheduleData { + + // The initial value for the dependency counters. It means that the + // dependencies are not calculated yet. + enum { InvalidDeps = -1 }; + + ScheduleData() + : Inst(nullptr), FirstInBundle(nullptr), NextInBundle(nullptr), + NextLoadStore(nullptr), SchedulingRegionID(0), SchedulingPriority(0), + Dependencies(InvalidDeps), UnscheduledDeps(InvalidDeps), + UnscheduledDepsInBundle(InvalidDeps), IsScheduled(false) {} + + void init(int BlockSchedulingRegionID) { + FirstInBundle = this; + NextInBundle = nullptr; + NextLoadStore = nullptr; + IsScheduled = false; + SchedulingRegionID = BlockSchedulingRegionID; + UnscheduledDepsInBundle = UnscheduledDeps; + clearDependencies(); + } + + /// Returns true if the dependency information has been calculated. + bool hasValidDependencies() const { return Dependencies != InvalidDeps; } + + /// Returns true for single instructions and for bundle representatives + /// (= the head of a bundle). + bool isSchedulingEntity() const { return FirstInBundle == this; } + + /// Returns true if it represents an instruction bundle and not only a + /// single instruction. + bool isPartOfBundle() const { + return NextInBundle != nullptr || FirstInBundle != this; + } + + /// Returns true if it is ready for scheduling, i.e. it has no more + /// unscheduled depending instructions/bundles. + bool isReady() const { + assert(isSchedulingEntity() && + "can't consider non-scheduling entity for ready list"); + return UnscheduledDepsInBundle == 0 && !IsScheduled; + } + + /// Modifies the number of unscheduled dependencies, also updating it for + /// the whole bundle. + int incrementUnscheduledDeps(int Incr) { + UnscheduledDeps += Incr; + return FirstInBundle->UnscheduledDepsInBundle += Incr; + } + + /// Sets the number of unscheduled dependencies to the number of + /// dependencies. + void resetUnscheduledDeps() { + incrementUnscheduledDeps(Dependencies - UnscheduledDeps); + } + + /// Clears all dependency information. + void clearDependencies() { + Dependencies = InvalidDeps; + resetUnscheduledDeps(); + MemoryDependencies.clear(); + } + + void dump(raw_ostream &os) const { + if (!isSchedulingEntity()) { + os << "/ " << *Inst; + } else if (NextInBundle) { + os << '[' << *Inst; + ScheduleData *SD = NextInBundle; + while (SD) { + os << ';' << *SD->Inst; + SD = SD->NextInBundle; + } + os << ']'; + } else { + os << *Inst; + } + } - /// \brief Get the corresponding instruction numbering list for a given - /// BasicBlock. The list is allocated lazily. - BlockNumbering &getBlockNumbering(BasicBlock *BB) { - auto I = BlocksNumbers.insert(std::make_pair(BB, BlockNumbering(BB))); - return I.first->second; - } + Instruction *Inst; + + /// Points to the head in an instruction bundle (and always to this for + /// single instructions). + ScheduleData *FirstInBundle; + + /// Single linked list of all instructions in a bundle. Null if it is a + /// single instruction. + ScheduleData *NextInBundle; + + /// Single linked list of all memory instructions (e.g. load, store, call) + /// in the block - until the end of the scheduling region. + ScheduleData *NextLoadStore; + + /// The dependent memory instructions. + /// This list is derived on demand in calculateDependencies(). + SmallVector MemoryDependencies; + + /// This ScheduleData is in the current scheduling region if this matches + /// the current SchedulingRegionID of BlockScheduling. + int SchedulingRegionID; + + /// Used for getting a "good" final ordering of instructions. + int SchedulingPriority; + + /// The number of dependencies. Constitutes of the number of users of the + /// instruction plus the number of dependent memory instructions (if any). + /// This value is calculated on demand. + /// If InvalidDeps, the number of dependencies is not calculated yet. + /// + int Dependencies; + + /// The number of dependencies minus the number of dependencies of scheduled + /// instructions. As soon as this is zero, the instruction/bundle gets ready + /// for scheduling. + /// Note that this is negative as long as Dependencies is not calculated. + int UnscheduledDeps; + + /// The sum of UnscheduledDeps in a bundle. Equals to UnscheduledDeps for + /// single instructions. + int UnscheduledDepsInBundle; + + /// True if this instruction is scheduled (or considered as scheduled in the + /// dry-run). + bool IsScheduled; + }; + + friend raw_ostream &operator<<(raw_ostream &os, + const BoUpSLP::ScheduleData &SD); + + /// Contains all scheduling data for a basic block. + /// + struct BlockScheduling { + + BlockScheduling(BasicBlock *BB) + : BB(BB), ChunkSize(BB->size()), ChunkPos(ChunkSize), + ScheduleStart(nullptr), ScheduleEnd(nullptr), + FirstLoadStoreInRegion(nullptr), LastLoadStoreInRegion(nullptr), + // Make sure that the initial SchedulingRegionID is greater than the + // initial SchedulingRegionID in ScheduleData (which is 0). + SchedulingRegionID(1) {} + + void clear() { + ReadyInsts.clear(); + ScheduleStart = nullptr; + ScheduleEnd = nullptr; + FirstLoadStoreInRegion = nullptr; + LastLoadStoreInRegion = nullptr; + + // Make a new scheduling region, i.e. all existing ScheduleData is not + // in the new region yet. + ++SchedulingRegionID; + } + + ScheduleData *getScheduleData(Value *V) { + ScheduleData *SD = ScheduleDataMap[V]; + if (SD && SD->SchedulingRegionID == SchedulingRegionID) + return SD; + return nullptr; + } + + bool isInSchedulingRegion(ScheduleData *SD) { + return SD->SchedulingRegionID == SchedulingRegionID; + } + + /// Marks an instruction as scheduled and puts all dependent ready + /// instructions into the ready-list. + template + void schedule(ScheduleData *SD, ReadyListType &ReadyList) { + SD->IsScheduled = true; + DEBUG(dbgs() << "SLP: schedule " << *SD << "\n"); + + ScheduleData *BundleMember = SD; + while (BundleMember) { + // Handle the def-use chain dependencies. + for (Use &U : BundleMember->Inst->operands()) { + ScheduleData *OpDef = getScheduleData(U.get()); + if (OpDef && OpDef->hasValidDependencies() && + OpDef->incrementUnscheduledDeps(-1) == 0) { + // There are no more unscheduled dependencies after decrementing, + // so we can put the dependent instruction into the ready list. + ScheduleData *DepBundle = OpDef->FirstInBundle; + assert(!DepBundle->IsScheduled && + "already scheduled bundle gets ready"); + ReadyList.insert(DepBundle); + DEBUG(dbgs() << "SLP: gets ready (def): " << *DepBundle << "\n"); + } + } + // Handle the memory dependencies. + for (ScheduleData *MemoryDepSD : BundleMember->MemoryDependencies) { + if (MemoryDepSD->incrementUnscheduledDeps(-1) == 0) { + // There are no more unscheduled dependencies after decrementing, + // so we can put the dependent instruction into the ready list. + ScheduleData *DepBundle = MemoryDepSD->FirstInBundle; + assert(!DepBundle->IsScheduled && + "already scheduled bundle gets ready"); + ReadyList.insert(DepBundle); + DEBUG(dbgs() << "SLP: gets ready (mem): " << *DepBundle << "\n"); + } + } + BundleMember = BundleMember->NextInBundle; + } + } + + /// Put all instructions into the ReadyList which are ready for scheduling. + template + void initialFillReadyList(ReadyListType &ReadyList) { + for (auto *I = ScheduleStart; I != ScheduleEnd; I = I->getNextNode()) { + ScheduleData *SD = getScheduleData(I); + if (SD->isSchedulingEntity() && SD->isReady()) { + ReadyList.insert(SD); + DEBUG(dbgs() << "SLP: initially in ready list: " << *I << "\n"); + } + } + } + + /// Checks if a bundle of instructions can be scheduled, i.e. has no + /// cyclic dependencies. This is only a dry-run, no instructions are + /// actually moved at this stage. + bool tryScheduleBundle(ArrayRef VL, AliasAnalysis *AA); + + /// Un-bundles a group of instructions. + void cancelScheduling(ArrayRef VL); + + /// Extends the scheduling region so that V is inside the region. + void extendSchedulingRegion(Value *V); + + /// Initialize the ScheduleData structures for new instructions in the + /// scheduling region. + void initScheduleData(Instruction *FromI, Instruction *ToI, + ScheduleData *PrevLoadStore, + ScheduleData *NextLoadStore); + + /// Updates the dependency information of a bundle and of all instructions/ + /// bundles which depend on the original bundle. + void calculateDependencies(ScheduleData *SD, bool InsertInReadyList, + AliasAnalysis *AA); + + /// Sets all instruction in the scheduling region to un-scheduled. + void resetSchedule(); + + BasicBlock *BB; + + /// Simple memory allocation for ScheduleData. + std::vector> ScheduleDataChunks; + + /// The size of a ScheduleData array in ScheduleDataChunks. + int ChunkSize; + + /// The allocator position in the current chunk, which is the last entry + /// of ScheduleDataChunks. + int ChunkPos; + + /// Attaches ScheduleData to Instruction. + /// Note that the mapping survives during all vectorization iterations, i.e. + /// ScheduleData structures are recycled. + DenseMap ScheduleDataMap; + + struct ReadyList : SmallVector { + void insert(ScheduleData *SD) { push_back(SD); } + }; + + /// The ready-list for scheduling (only used for the dry-run). + ReadyList ReadyInsts; + + /// The first instruction of the scheduling region. + Instruction *ScheduleStart; + + /// The first instruction _after_ the scheduling region. + Instruction *ScheduleEnd; + + /// The first memory accessing instruction in the scheduling region + /// (can be null). + ScheduleData *FirstLoadStoreInRegion; + + /// The last memory accessing instruction in the scheduling region + /// (can be null). + ScheduleData *LastLoadStoreInRegion; + + /// The ID of the scheduling region. For a new vectorization iteration this + /// is incremented which "removes" all ScheduleData from the region. + int SchedulingRegionID; + }; + + /// Attaches the BlockScheduling structures to basic blocks. + DenseMap> BlocksSchedules; + + /// Performs the "real" scheduling. Done before vectorization is actually + /// performed in a basic block. + void scheduleBlock(BasicBlock *BB); /// List of users to ignore during scheduling and that don't need extracting. ArrayRef UserIgnoreList; @@ -609,6 +827,11 @@ private: /// Instruction builder to construct the vectorized tree. IRBuilder<> Builder; }; + +raw_ostream &operator<<(raw_ostream &os, const BoUpSLP::ScheduleData &SD) { + SD.dump(os); + return os; +} void BoUpSLP::buildTree(ArrayRef Roots, ArrayRef UserIgnoreLst) { @@ -743,69 +966,8 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { // Check that all of the users of the scalars that we want to vectorize are // schedulable. Instruction *VL0 = cast(VL[0]); - int MyLastIndex = getLastIndex(VL); BasicBlock *BB = cast(VL0)->getParent(); - for (unsigned i = 0, e = VL.size(); i != e; ++i) { - Instruction *Scalar = cast(VL[i]); - DEBUG(dbgs() << "SLP: Checking users of " << *Scalar << ". \n"); - for (User *U : Scalar->users()) { - DEBUG(dbgs() << "SLP: \tUser " << *U << ". \n"); - Instruction *UI = dyn_cast(U); - if (!UI) { - DEBUG(dbgs() << "SLP: Gathering due unknown user. \n"); - newTreeEntry(VL, false); - return; - } - - // We don't care if the user is in a different basic block. - BasicBlock *UserBlock = UI->getParent(); - if (UserBlock != BB) { - DEBUG(dbgs() << "SLP: User from a different basic block " - << *UI << ". \n"); - continue; - } - - // If this is a PHINode within this basic block then we can place the - // extract wherever we want. - if (isa(*UI)) { - DEBUG(dbgs() << "SLP: \tWe can schedule PHIs:" << *UI << ". \n"); - continue; - } - - // Check if this is a safe in-tree user. - if (ScalarToTreeEntry.count(UI)) { - int Idx = ScalarToTreeEntry[UI]; - int VecLocation = VectorizableTree[Idx].LastScalarIndex; - if (VecLocation <= MyLastIndex) { - DEBUG(dbgs() << "SLP: Gathering due to unschedulable vector. \n"); - newTreeEntry(VL, false); - return; - } - DEBUG(dbgs() << "SLP: In-tree user (" << *UI << ") at #" << - VecLocation << " vector value (" << *Scalar << ") at #" - << MyLastIndex << ".\n"); - continue; - } - - // Ignore users in the user ignore list. - if (std::find(UserIgnoreList.begin(), UserIgnoreList.end(), UI) != - UserIgnoreList.end()) - continue; - - // Make sure that we can schedule this unknown user. - BlockNumbering &BN = getBlockNumbering(BB); - int UserIndex = BN.getIndex(UI); - if (UserIndex < MyLastIndex) { - - DEBUG(dbgs() << "SLP: Can't schedule extractelement for " - << *UI << ". \n"); - newTreeEntry(VL, false); - return; - } - } - } - // Check that every instructions appears once in this bundle. for (unsigned i = 0, e = VL.size(); i < e; ++i) for (unsigned j = i+1; j < e; ++j) @@ -815,38 +977,19 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { return; } - // Check that instructions in this bundle don't reference other instructions. - // The runtime of this check is O(N * N-1 * uses(N)) and a typical N is 4. - for (unsigned i = 0, e = VL.size(); i < e; ++i) { - for (User *U : VL[i]->users()) { - for (unsigned j = 0; j < e; ++j) { - if (i != j && U == VL[j]) { - DEBUG(dbgs() << "SLP: Intra-bundle dependencies!" << *U << ". \n"); - newTreeEntry(VL, false); - return; - } - } - } + auto &BSRef = BlocksSchedules[BB]; + if (!BSRef) { + BSRef = llvm::make_unique(BB); } + BlockScheduling &BS = *BSRef.get(); - DEBUG(dbgs() << "SLP: We are able to schedule this bundle.\n"); - - // Check if it is safe to sink the loads or the stores. - if (Opcode == Instruction::Load || Opcode == Instruction::Store) { - Instruction *Last = getLastInstruction(VL); - - for (unsigned i = 0, e = VL.size(); i < e; ++i) { - if (VL[i] == Last) - continue; - Value *Barrier = getSinkBarrier(cast(VL[i]), Last); - if (Barrier) { - DEBUG(dbgs() << "SLP: Can't sink " << *VL[i] << "\n down to " << *Last - << "\n because of " << *Barrier << ". Gathering.\n"); - newTreeEntry(VL, false); - return; - } - } + if (!BS.tryScheduleBundle(VL, AA)) { + DEBUG(dbgs() << "SLP: We are not able to schedule this bundle!\n"); + BS.cancelScheduling(VL); + newTreeEntry(VL, false); + return; } + DEBUG(dbgs() << "SLP: We are able to schedule this bundle.\n"); switch (Opcode) { case Instruction::PHI: { @@ -859,6 +1002,7 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { cast(VL[j])->getIncomingValueForBlock(PH->getIncomingBlock(i))); if (Term) { DEBUG(dbgs() << "SLP: Need to swizzle PHINodes (TerminatorInst use).\n"); + BS.cancelScheduling(VL); newTreeEntry(VL, false); return; } @@ -882,6 +1026,8 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { bool Reuse = CanReuseExtract(VL); if (Reuse) { DEBUG(dbgs() << "SLP: Reusing extract sequence.\n"); + } else { + BS.cancelScheduling(VL); } newTreeEntry(VL, Reuse); return; @@ -891,6 +1037,7 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { for (unsigned i = 0, e = VL.size() - 1; i < e; ++i) { LoadInst *L = cast(VL[i]); if (!L->isSimple()) { + BS.cancelScheduling(VL); newTreeEntry(VL, false); DEBUG(dbgs() << "SLP: Gathering non-simple loads.\n"); return; @@ -899,6 +1046,7 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { if (VL.size() == 2 && isConsecutiveAccess(VL[1], VL[0])) { ++NumLoadsWantToChangeOrder; } + BS.cancelScheduling(VL); newTreeEntry(VL, false); DEBUG(dbgs() << "SLP: Gathering non-consecutive loads.\n"); return; @@ -925,6 +1073,7 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { for (unsigned i = 0; i < VL.size(); ++i) { Type *Ty = cast(VL[i])->getOperand(0)->getType(); if (Ty != SrcTy || Ty->isAggregateType() || Ty->isVectorTy()) { + BS.cancelScheduling(VL); newTreeEntry(VL, false); DEBUG(dbgs() << "SLP: Gathering casts with different src types.\n"); return; @@ -952,6 +1101,7 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { CmpInst *Cmp = cast(VL[i]); if (Cmp->getPredicate() != P0 || Cmp->getOperand(0)->getType() != ComparedTy) { + BS.cancelScheduling(VL); newTreeEntry(VL, false); DEBUG(dbgs() << "SLP: Gathering cmp with different predicate.\n"); return; @@ -998,20 +1148,8 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { if (isa(VL0) && VL0->isCommutative()) { ValueList Left, Right; reorderInputsAccordingToOpcode(VL, Left, Right); - BasicBlock *LeftBB = getSameBlock(Left); - BasicBlock *RightBB = getSameBlock(Right); - // If we have common uses on separate paths in the tree make sure we - // process the one with greater common depth first. - // We can use block numbering to determine the subtree traversal as - // earler user has to come in between the common use and the later user. - if (LeftBB && RightBB && LeftBB == RightBB && - getLastIndex(Right) > getLastIndex(Left)) { - buildTree_rec(Right, Depth + 1); - buildTree_rec(Left, Depth + 1); - } else { - buildTree_rec(Left, Depth + 1); - buildTree_rec(Right, Depth + 1); - } + buildTree_rec(Left, Depth + 1); + buildTree_rec(Right, Depth + 1); return; } @@ -1030,6 +1168,7 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { for (unsigned j = 0; j < VL.size(); ++j) { if (cast(VL[j])->getNumOperands() != 2) { DEBUG(dbgs() << "SLP: not-vectorizable GEP (nested indexes).\n"); + BS.cancelScheduling(VL); newTreeEntry(VL, false); return; } @@ -1042,6 +1181,7 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { Type *CurTy = cast(VL[j])->getOperand(0)->getType(); if (Ty0 != CurTy) { DEBUG(dbgs() << "SLP: not-vectorizable GEP (different types).\n"); + BS.cancelScheduling(VL); newTreeEntry(VL, false); return; } @@ -1053,6 +1193,7 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { if (!isa(Op)) { DEBUG( dbgs() << "SLP: not-vectorizable GEP (non-constant indexes).\n"); + BS.cancelScheduling(VL); newTreeEntry(VL, false); return; } @@ -1074,6 +1215,7 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { // Check if the stores are consecutive or of we need to swizzle them. for (unsigned i = 0, e = VL.size() - 1; i < e; ++i) if (!isConsecutiveAccess(VL[i], VL[i + 1])) { + BS.cancelScheduling(VL); newTreeEntry(VL, false); DEBUG(dbgs() << "SLP: Non-consecutive store.\n"); return; @@ -1086,8 +1228,6 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { for (unsigned j = 0; j < VL.size(); ++j) Operands.push_back(cast(VL[j])->getOperand(0)); - // We can ignore these values because we are sinking them down. - MemBarrierIgnoreList.insert(VL.begin(), VL.end()); buildTree_rec(Operands, Depth + 1); return; } @@ -1098,6 +1238,7 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { // represented by an intrinsic call Intrinsic::ID ID = getIntrinsicIDForCall(CI, TLI); if (!isTriviallyVectorizable(ID)) { + BS.cancelScheduling(VL); newTreeEntry(VL, false); DEBUG(dbgs() << "SLP: Non-vectorizable call.\n"); return; @@ -1110,6 +1251,7 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { CallInst *CI2 = dyn_cast(VL[i]); if (!CI2 || CI2->getCalledFunction() != Int || getIntrinsicIDForCall(CI2, TLI) != ID) { + BS.cancelScheduling(VL); newTreeEntry(VL, false); DEBUG(dbgs() << "SLP: mismatched calls:" << *CI << "!=" << *VL[i] << "\n"); @@ -1120,6 +1262,7 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { if (hasVectorInstrinsicScalarOpd(ID, 1)) { Value *A1J = CI2->getArgOperand(1); if (A1I != A1J) { + BS.cancelScheduling(VL); newTreeEntry(VL, false); DEBUG(dbgs() << "SLP: mismatched arguments in call:" << *CI << " argument "<< A1I<<"!=" << A1J @@ -1145,6 +1288,7 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { // If this is not an alternate sequence of opcode like add-sub // then do not vectorize this instruction. if (!isAltShuffle) { + BS.cancelScheduling(VL); newTreeEntry(VL, false); DEBUG(dbgs() << "SLP: ShuffleVector are not vectorized.\n"); return; @@ -1162,6 +1306,7 @@ void BoUpSLP::buildTree_rec(ArrayRef VL, unsigned Depth) { return; } default: + BS.cancelScheduling(VL); newTreeEntry(VL, false); DEBUG(dbgs() << "SLP: Gathering unknown instruction.\n"); return; @@ -1450,14 +1595,6 @@ int BoUpSLP::getGatherCost(ArrayRef VL) { return getGatherCost(VecTy); } -AliasAnalysis::Location BoUpSLP::getLocation(Instruction *I) { - if (StoreInst *SI = dyn_cast(I)) - return AA->getLocation(SI); - if (LoadInst *LI = dyn_cast(I)) - return AA->getLocation(LI); - return AliasAnalysis::Location(); -} - Value *BoUpSLP::getPointerOperand(Value *I) { if (LoadInst *LI = dyn_cast(I)) return LI->getPointerOperand(); @@ -1515,59 +1652,9 @@ bool BoUpSLP::isConsecutiveAccess(Value *A, Value *B) { return X == PtrSCEVB; } -Value *BoUpSLP::getSinkBarrier(Instruction *Src, Instruction *Dst) { - assert(Src->getParent() == Dst->getParent() && "Not the same BB"); - BasicBlock::iterator I = Src, E = Dst; - /// Scan all of the instruction from SRC to DST and check if - /// the source may alias. - for (++I; I != E; ++I) { - // Ignore store instructions that are marked as 'ignore'. - if (MemBarrierIgnoreList.count(I)) - continue; - if (Src->mayWriteToMemory()) /* Write */ { - if (!I->mayReadOrWriteMemory()) - continue; - } else /* Read */ { - if (!I->mayWriteToMemory()) - continue; - } - AliasAnalysis::Location A = getLocation(&*I); - AliasAnalysis::Location B = getLocation(Src); - - if (!A.Ptr || !B.Ptr || AA->alias(A, B)) - return I; - } - return nullptr; -} - -int BoUpSLP::getLastIndex(ArrayRef VL) { - BasicBlock *BB = cast(VL[0])->getParent(); - assert(BB == getSameBlock(VL) && "Invalid block"); - BlockNumbering &BN = getBlockNumbering(BB); - - int MaxIdx = BN.getIndex(BB->getFirstNonPHI()); - for (unsigned i = 0, e = VL.size(); i < e; ++i) - MaxIdx = std::max(MaxIdx, BN.getIndex(cast(VL[i]))); - return MaxIdx; -} - -Instruction *BoUpSLP::getLastInstruction(ArrayRef VL) { - BasicBlock *BB = cast(VL[0])->getParent(); - assert(BB == getSameBlock(VL) && "Invalid block"); - BlockNumbering &BN = getBlockNumbering(BB); - - int MaxIdx = BN.getIndex(cast(VL[0])); - for (unsigned i = 1, e = VL.size(); i < e; ++i) - MaxIdx = std::max(MaxIdx, BN.getIndex(cast(VL[i]))); - Instruction *I = BN.getInstruction(MaxIdx); - assert(I && "bad location"); - return I; -} - void BoUpSLP::setInsertPointAfterBundle(ArrayRef VL) { Instruction *VL0 = cast(VL[0]); - Instruction *LastInst = getLastInstruction(VL); - BasicBlock::iterator NextInst = LastInst; + BasicBlock::iterator NextInst = VL0; ++NextInst; Builder.SetInsertPoint(VL0->getParent(), NextInst); Builder.SetCurrentDebugLocation(VL0->getDebugLoc()); @@ -1650,6 +1737,9 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) { setInsertPointAfterBundle(E->Scalars); return Gather(E->Scalars, VecTy); } + BasicBlock *BB = VL0->getParent(); + scheduleBlock(BB); + unsigned Opcode = getSameOpcode(E->Scalars); switch (Opcode) { @@ -2070,9 +2160,6 @@ Value *BoUpSLP::vectorizeTree() { } } - for (auto &BN : BlocksNumbers) - BN.second.forget(); - Builder.ClearInsertionPoint(); return VectorizableTree[0].VectorizedValue; @@ -2166,6 +2253,363 @@ void BoUpSLP::optimizeGatherSequence() { GatherSeq.clear(); } +// Groups the instructions to a bundle (which is then a single scheduling entity) +// and schedules instructions until the bundle gets ready. +bool BoUpSLP::BlockScheduling::tryScheduleBundle(ArrayRef VL, + AliasAnalysis *AA) { + if (isa(VL[0])) + return true; + + // Initialize the instruction bundle. + Instruction *OldScheduleEnd = ScheduleEnd; + ScheduleData *PrevInBundle = nullptr; + ScheduleData *Bundle = nullptr; + bool ReSchedule = false; + DEBUG(dbgs() << "SLP: bundle: " << *VL[0] << "\n"); + for (Value *V : VL) { + extendSchedulingRegion(V); + ScheduleData *BundleMember = getScheduleData(V); + assert(BundleMember && + "no ScheduleData for bundle member (maybe not in same basic block)"); + if (BundleMember->IsScheduled) { + // A bundle member was scheduled as single instruction before and now + // needs to be scheduled as part of the bundle. We just get rid of the + // existing schedule. + DEBUG(dbgs() << "SLP: reset schedule because " << *BundleMember + << " was already scheduled\n"); + ReSchedule = true; + } + assert(BundleMember->isSchedulingEntity() && + "bundle member already part of other bundle"); + if (PrevInBundle) { + PrevInBundle->NextInBundle = BundleMember; + } else { + Bundle = BundleMember; + } + BundleMember->UnscheduledDepsInBundle = 0; + Bundle->UnscheduledDepsInBundle += BundleMember->UnscheduledDeps; + + // Group the instructions to a bundle. + BundleMember->FirstInBundle = Bundle; + PrevInBundle = BundleMember; + } + if (ScheduleEnd != OldScheduleEnd) { + // The scheduling region got new instructions at the lower end (or it is a + // new region for the first bundle). This makes it necessary to + // recalculate all dependencies. + // It is seldom that this needs to be done a second time after adding the + // initial bundle to the region. + for (auto *I = ScheduleStart; I != ScheduleEnd; I = I->getNextNode()) { + ScheduleData *SD = getScheduleData(I); + SD->clearDependencies(); + } + ReSchedule = true; + } + if (ReSchedule) { + resetSchedule(); + initialFillReadyList(ReadyInsts); + } + + DEBUG(dbgs() << "SLP: try schedule bundle " << *Bundle << " in block " + << BB->getName() << "\n"); + + calculateDependencies(Bundle, true, AA); + + // Now try to schedule the new bundle. As soon as the bundle is "ready" it + // means that there are no cyclic dependencies and we can schedule it. + // Note that's important that we don't "schedule" the bundle yet (see + // cancelScheduling). + while (!Bundle->isReady() && !ReadyInsts.empty()) { + + ScheduleData *pickedSD = ReadyInsts.back(); + ReadyInsts.pop_back(); + + if (pickedSD->isSchedulingEntity() && pickedSD->isReady()) { + schedule(pickedSD, ReadyInsts); + } + } + return Bundle->isReady(); +} + +void BoUpSLP::BlockScheduling::cancelScheduling(ArrayRef VL) { + if (isa(VL[0])) + return; + + ScheduleData *Bundle = getScheduleData(VL[0]); + DEBUG(dbgs() << "SLP: cancel scheduling of " << *Bundle << "\n"); + assert(!Bundle->IsScheduled && + "Can't cancel bundle which is already scheduled"); + assert(Bundle->isSchedulingEntity() && Bundle->isPartOfBundle() && + "tried to unbundle something which is not a bundle"); + + // Un-bundle: make single instructions out of the bundle. + ScheduleData *BundleMember = Bundle; + while (BundleMember) { + assert(BundleMember->FirstInBundle == Bundle && "corrupt bundle links"); + BundleMember->FirstInBundle = BundleMember; + ScheduleData *Next = BundleMember->NextInBundle; + BundleMember->NextInBundle = nullptr; + BundleMember->UnscheduledDepsInBundle = BundleMember->UnscheduledDeps; + if (BundleMember->UnscheduledDepsInBundle == 0) { + ReadyInsts.insert(BundleMember); + } + BundleMember = Next; + } +} + +void BoUpSLP::BlockScheduling::extendSchedulingRegion(Value *V) { + if (getScheduleData(V)) + return; + Instruction *I = dyn_cast(V); + assert(I && "bundle member must be an instruction"); + assert(!isa(I) && "phi nodes don't need to be scheduled"); + if (!ScheduleStart) { + // It's the first instruction in the new region. + initScheduleData(I, I->getNextNode(), nullptr, nullptr); + ScheduleStart = I; + ScheduleEnd = I->getNextNode(); + assert(ScheduleEnd && "tried to vectorize a TerminatorInst?"); + DEBUG(dbgs() << "SLP: initialize schedule region to " << *I << "\n"); + return; + } + // Search up and down at the same time, because we don't know if the new + // instruction is above or below the existing scheduling region. + BasicBlock::reverse_iterator UpIter(ScheduleStart); + BasicBlock::reverse_iterator UpperEnd = BB->rend(); + BasicBlock::iterator DownIter(ScheduleEnd); + BasicBlock::iterator LowerEnd = BB->end(); + for (;;) { + if (UpIter != UpperEnd) { + if (&*UpIter == I) { + initScheduleData(I, ScheduleStart, nullptr, FirstLoadStoreInRegion); + ScheduleStart = I; + DEBUG(dbgs() << "SLP: extend schedule region start to " << *I << "\n"); + return; + } + UpIter++; + } + if (DownIter != LowerEnd) { + if (&*DownIter == I) { + initScheduleData(ScheduleEnd, I->getNextNode(), LastLoadStoreInRegion, + nullptr); + ScheduleEnd = I->getNextNode(); + assert(ScheduleEnd && "tried to vectorize a TerminatorInst?"); + DEBUG(dbgs() << "SLP: extend schedule region end to " << *I << "\n"); + return; + } + DownIter++; + } + assert((UpIter != UpperEnd || DownIter != LowerEnd) && + "instruction not found in block"); + } +} + +void BoUpSLP::BlockScheduling::initScheduleData(Instruction *FromI, + Instruction *ToI, + ScheduleData *PrevLoadStore, + ScheduleData *NextLoadStore) { + ScheduleData *CurrentLoadStore = PrevLoadStore; + for (Instruction *I = FromI; I != ToI; I = I->getNextNode()) { + ScheduleData *SD = ScheduleDataMap[I]; + if (!SD) { + // Allocate a new ScheduleData for the instruction. + if (ChunkPos >= ChunkSize) { + ScheduleDataChunks.push_back( + llvm::make_unique(ChunkSize)); + ChunkPos = 0; + } + SD = &(ScheduleDataChunks.back()[ChunkPos++]); + ScheduleDataMap[I] = SD; + SD->Inst = I; + } + assert(!isInSchedulingRegion(SD) && + "new ScheduleData already in scheduling region"); + SD->init(SchedulingRegionID); + + if (I->mayReadOrWriteMemory()) { + // Update the linked list of memory accessing instructions. + if (CurrentLoadStore) { + CurrentLoadStore->NextLoadStore = SD; + } else { + FirstLoadStoreInRegion = SD; + } + CurrentLoadStore = SD; + } + } + if (NextLoadStore) { + if (CurrentLoadStore) + CurrentLoadStore->NextLoadStore = NextLoadStore; + } else { + LastLoadStoreInRegion = CurrentLoadStore; + } +} + +/// \returns the AA location that is being access by the instruction. +static AliasAnalysis::Location getLocation(Instruction *I, AliasAnalysis *AA) { + if (StoreInst *SI = dyn_cast(I)) + return AA->getLocation(SI); + if (LoadInst *LI = dyn_cast(I)) + return AA->getLocation(LI); + return AliasAnalysis::Location(); +} + +void BoUpSLP::BlockScheduling::calculateDependencies(ScheduleData *SD, + bool InsertInReadyList, + AliasAnalysis *AA) { + assert(SD->isSchedulingEntity()); + + SmallVector WorkList; + WorkList.push_back(SD); + + while (!WorkList.empty()) { + ScheduleData *SD = WorkList.back(); + WorkList.pop_back(); + + ScheduleData *BundleMember = SD; + while (BundleMember) { + assert(isInSchedulingRegion(BundleMember)); + if (!BundleMember->hasValidDependencies()) { + + DEBUG(dbgs() << "SLP: update deps of " << *BundleMember << "\n"); + BundleMember->Dependencies = 0; + BundleMember->resetUnscheduledDeps(); + + // Handle def-use chain dependencies. + for (User *U : BundleMember->Inst->users()) { + if (isa(U)) { + ScheduleData *UseSD = getScheduleData(U); + if (UseSD && isInSchedulingRegion(UseSD->FirstInBundle)) { + BundleMember->Dependencies++; + ScheduleData *DestBundle = UseSD->FirstInBundle; + if (!DestBundle->IsScheduled) { + BundleMember->incrementUnscheduledDeps(1); + } + if (!DestBundle->hasValidDependencies()) { + WorkList.push_back(DestBundle); + } + } + } else { + // I'm not sure if this can ever happen. But we need to be safe. + // This lets the instruction/bundle never be scheduled and eventally + // disable vectorization. + BundleMember->Dependencies++; + BundleMember->incrementUnscheduledDeps(1); + } + } + + // Handle the memory dependencies. + ScheduleData *DepDest = BundleMember->NextLoadStore; + if (DepDest) { + AliasAnalysis::Location SrcLoc = getLocation(BundleMember->Inst, AA); + bool SrcMayWrite = BundleMember->Inst->mayWriteToMemory(); + + while (DepDest) { + assert(isInSchedulingRegion(DepDest)); + if (SrcMayWrite || DepDest->Inst->mayWriteToMemory()) { + AliasAnalysis::Location DstLoc = getLocation(DepDest->Inst, AA); + if (!SrcLoc.Ptr || !DstLoc.Ptr || AA->alias(SrcLoc, DstLoc)) { + DepDest->MemoryDependencies.push_back(BundleMember); + BundleMember->Dependencies++; + ScheduleData *DestBundle = DepDest->FirstInBundle; + if (!DestBundle->IsScheduled) { + BundleMember->incrementUnscheduledDeps(1); + } + if (!DestBundle->hasValidDependencies()) { + WorkList.push_back(DestBundle); + } + } + } + DepDest = DepDest->NextLoadStore; + } + } + } + BundleMember = BundleMember->NextInBundle; + } + if (InsertInReadyList && SD->isReady()) { + ReadyInsts.push_back(SD); + DEBUG(dbgs() << "SLP: gets ready on update: " << *SD->Inst << "\n"); + } + } +} + +void BoUpSLP::BlockScheduling::resetSchedule() { + assert(ScheduleStart && + "tried to reset schedule on block which has not been scheduled"); + for (Instruction *I = ScheduleStart; I != ScheduleEnd; I = I->getNextNode()) { + ScheduleData *SD = getScheduleData(I); + assert(isInSchedulingRegion(SD)); + SD->IsScheduled = false; + SD->resetUnscheduledDeps(); + } + ReadyInsts.clear(); +} + +void BoUpSLP::scheduleBlock(BasicBlock *BB) { + DEBUG(dbgs() << "SLP: schedule block " << BB->getName() << "\n"); + + BlockScheduling *BS = BlocksSchedules[BB].get(); + if (!BS || !BS->ScheduleStart) + return; + + BS->resetSchedule(); + + // For the real scheduling we use a more sophisticated ready-list: it is + // sorted by the original instruction location. This lets the final schedule + // be as close as possible to the original instruction order. + struct ScheduleDataCompare { + bool operator()(ScheduleData *SD1, ScheduleData *SD2) { + return SD2->SchedulingPriority < SD1->SchedulingPriority; + } + }; + std::set ReadyInsts; + + // Ensure that all depencency data is updated and fill the ready-list with + // initial instructions. + int Idx = 0; + int NumToSchedule = 0; + for (auto *I = BS->ScheduleStart; I != BS->ScheduleEnd; + I = I->getNextNode()) { + ScheduleData *SD = BS->getScheduleData(I); + assert( + SD->isPartOfBundle() == (ScalarToTreeEntry.count(SD->Inst) != 0) && + "scheduler and vectorizer have different opinion on what is a bundle"); + SD->FirstInBundle->SchedulingPriority = Idx++; + if (SD->isSchedulingEntity()) { + BS->calculateDependencies(SD, false, AA); + NumToSchedule++; + } + } + BS->initialFillReadyList(ReadyInsts); + + Instruction *LastScheduledInst = BS->ScheduleEnd; + + // Do the "real" scheduling. + while (!ReadyInsts.empty()) { + ScheduleData *picked = *ReadyInsts.begin(); + ReadyInsts.erase(ReadyInsts.begin()); + + // Move the scheduled instruction(s) to their dedicated places, if not + // there yet. + ScheduleData *BundleMember = picked; + while (BundleMember) { + Instruction *pickedInst = BundleMember->Inst; + if (LastScheduledInst->getNextNode() != pickedInst) { + BB->getInstList().remove(pickedInst); + BB->getInstList().insert(LastScheduledInst, pickedInst); + } + LastScheduledInst = pickedInst; + BundleMember = BundleMember->NextInBundle; + } + + BS->schedule(picked, ReadyInsts); + NumToSchedule--; + } + assert(NumToSchedule == 0 && "could not schedule all instructions"); + + // Avoid duplicate scheduling of the block. + BS->ScheduleStart = nullptr; +} + /// The SLPVectorizer Pass. struct SLPVectorizer : public FunctionPass { typedef SmallVector StoreList; diff --git a/llvm/test/Transforms/SLPVectorizer/X86/crash_vectorizeTree.ll b/llvm/test/Transforms/SLPVectorizer/X86/crash_vectorizeTree.ll index c7ec98a..9f1fb71 100644 --- a/llvm/test/Transforms/SLPVectorizer/X86/crash_vectorizeTree.ll +++ b/llvm/test/Transforms/SLPVectorizer/X86/crash_vectorizeTree.ll @@ -1,4 +1,4 @@ -; RUN: opt -slp-vectorizer -mtriple=x86_64-apple-macosx10.9.0 -mcpu=corei7-avx -S < %s | FileCheck %s +; RUN: opt -basicaa -slp-vectorizer -mtriple=x86_64-apple-macosx10.9.0 -mcpu=corei7-avx -S < %s | FileCheck %s target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" target triple = "x86_64-apple-macosx10.9.0" diff --git a/llvm/test/Transforms/SLPVectorizer/X86/in-tree-user.ll b/llvm/test/Transforms/SLPVectorizer/X86/in-tree-user.ll index 3115232..194a0fb 100644 --- a/llvm/test/Transforms/SLPVectorizer/X86/in-tree-user.ll +++ b/llvm/test/Transforms/SLPVectorizer/X86/in-tree-user.ll @@ -5,9 +5,11 @@ target triple = "x86_64-apple-macosx10.7.0" @.str = private unnamed_addr constant [6 x i8] c"bingo\00", align 1 -; We can't vectorize when the roots are used inside the tree. +; Uses inside the tree must be scheduled after the corresponding tree bundle. ;CHECK-LABEL: @in_tree_user( -;CHECK-NOT: load <2 x double> +;CHECK: load <2 x double> +;CHECK: fadd <2 x double> +;CHECK: InTreeUser = fadd ;CHECK: ret define void @in_tree_user(double* nocapture %A, i32 %n) { entry: @@ -22,7 +24,7 @@ for.body: ; preds = %for.inc, %entry %mul1 = fmul double %conv, %1 %mul2 = fmul double %mul1, 7.000000e+00 %add = fadd double %mul2, 5.000000e+00 - %BadValue = fadd double %add, %add ; <------------------ In tree user. + %InTreeUser = fadd double %add, %add ; <------------------ In tree user. %2 = or i64 %0, 1 %arrayidx6 = getelementptr inbounds double* %A, i64 %2 %3 = load double* %arrayidx6, align 8 @@ -43,6 +45,7 @@ for.inc: ; preds = %for.body, %if.then br i1 %exitcond, label %for.end, label %for.body for.end: ; preds = %for.inc + store double %InTreeUser, double* %A, align 8 ; Avoid dead code elimination of the InTreeUser. ret void } diff --git a/llvm/test/Transforms/SLPVectorizer/X86/scheduling.ll b/llvm/test/Transforms/SLPVectorizer/X86/scheduling.ll new file mode 100644 index 0000000..2ff3273 --- /dev/null +++ b/llvm/test/Transforms/SLPVectorizer/X86/scheduling.ll @@ -0,0 +1,78 @@ +; RUN: opt < %s -basicaa -slp-vectorizer -S -mtriple=i386-apple-macosx10.8.0 -mcpu=corei7-avx | FileCheck %s + +target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-apple-macosx10.9.0" + +;CHECK-LABEL: @foo +;CHECK: load <4 x i32> +;CHECK: load <4 x i32> +;CHECK: %[[S1:.+]] = add <4 x i32> +;CHECK-DAG: store <4 x i32> %[[S1]] +;CHECK-DAG: %[[A1:.+]] = add nsw i32 +;CHECK-DAG: %[[A2:.+]] = add nsw i32 %[[A1]] +;CHECK-DAG: %[[A3:.+]] = add nsw i32 %[[A2]] +;CHECK-DAG: %[[A4:.+]] = add nsw i32 %[[A3]] +;CHECK: ret i32 %[[A4]] + +define i32 @foo(i32* nocapture readonly %diff) #0 { +entry: + %m2 = alloca [8 x [8 x i32]], align 16 + %0 = bitcast [8 x [8 x i32]]* %m2 to i8* + br label %for.body + +for.body: ; preds = %for.body, %entry + %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ] + %a.088 = phi i32 [ 0, %entry ], [ %add52, %for.body ] + %1 = shl i64 %indvars.iv, 3 + %arrayidx = getelementptr inbounds i32* %diff, i64 %1 + %2 = load i32* %arrayidx, align 4 + %3 = or i64 %1, 4 + %arrayidx2 = getelementptr inbounds i32* %diff, i64 %3 + %4 = load i32* %arrayidx2, align 4 + %add3 = add nsw i32 %4, %2 + %arrayidx6 = getelementptr inbounds [8 x [8 x i32]]* %m2, i64 0, i64 %indvars.iv, i64 0 + store i32 %add3, i32* %arrayidx6, align 16 + %add10 = add nsw i32 %add3, %a.088 + %5 = or i64 %1, 1 + %arrayidx13 = getelementptr inbounds i32* %diff, i64 %5 + %6 = load i32* %arrayidx13, align 4 + %7 = or i64 %1, 5 + %arrayidx16 = getelementptr inbounds i32* %diff, i64 %7 + %8 = load i32* %arrayidx16, align 4 + %add17 = add nsw i32 %8, %6 + %arrayidx20 = getelementptr inbounds [8 x [8 x i32]]* %m2, i64 0, i64 %indvars.iv, i64 1 + store i32 %add17, i32* %arrayidx20, align 4 + %add24 = add nsw i32 %add10, %add17 + %9 = or i64 %1, 2 + %arrayidx27 = getelementptr inbounds i32* %diff, i64 %9 + %10 = load i32* %arrayidx27, align 4 + %11 = or i64 %1, 6 + %arrayidx30 = getelementptr inbounds i32* %diff, i64 %11 + %12 = load i32* %arrayidx30, align 4 + %add31 = add nsw i32 %12, %10 + %arrayidx34 = getelementptr inbounds [8 x [8 x i32]]* %m2, i64 0, i64 %indvars.iv, i64 2 + store i32 %add31, i32* %arrayidx34, align 8 + %add38 = add nsw i32 %add24, %add31 + %13 = or i64 %1, 3 + %arrayidx41 = getelementptr inbounds i32* %diff, i64 %13 + %14 = load i32* %arrayidx41, align 4 + %15 = or i64 %1, 7 + %arrayidx44 = getelementptr inbounds i32* %diff, i64 %15 + %16 = load i32* %arrayidx44, align 4 + %add45 = add nsw i32 %16, %14 + %arrayidx48 = getelementptr inbounds [8 x [8 x i32]]* %m2, i64 0, i64 %indvars.iv, i64 3 + store i32 %add45, i32* %arrayidx48, align 4 + %add52 = add nsw i32 %add38, %add45 + %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 + %exitcond = icmp eq i64 %indvars.iv.next, 8 + br i1 %exitcond, label %for.end, label %for.body + +for.end: ; preds = %for.body + %arraydecay = getelementptr inbounds [8 x [8 x i32]]* %m2, i64 0, i64 0 + call void @ff([8 x i32]* %arraydecay) #1 + ret i32 %add52 +} + +declare void @ff([8 x i32]*) #2 + + -- 2.7.4