1 //===- SLPVectorizer.cpp - A bottom up SLP Vectorizer ---------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
9 // This pass implements the Bottom Up SLP vectorizer. It detects consecutive
10 // stores that can be put together into vector-stores. Next, it attempts to
11 // construct vectorizable tree using the use-def chains. If a profitable tree
12 // was found, the SLP vectorizer performs vectorization on the tree.
14 // The pass is inspired by the work described in the paper:
15 // "Loop-Aware SLP in GCC" by Ira Rosen, Dorit Nuzman, Ayal Zaks.
17 //===----------------------------------------------------------------------===//
18 #include "llvm/Transforms/Vectorize.h"
19 #include "llvm/ADT/MapVector.h"
20 #include "llvm/ADT/Optional.h"
21 #include "llvm/ADT/PostOrderIterator.h"
22 #include "llvm/ADT/SetVector.h"
23 #include "llvm/ADT/Statistic.h"
24 #include "llvm/Analysis/AliasAnalysis.h"
25 #include "llvm/Analysis/AssumptionCache.h"
26 #include "llvm/Analysis/CodeMetrics.h"
27 #include "llvm/Analysis/LoopInfo.h"
28 #include "llvm/Analysis/ScalarEvolution.h"
29 #include "llvm/Analysis/ScalarEvolutionExpressions.h"
30 #include "llvm/Analysis/TargetTransformInfo.h"
31 #include "llvm/Analysis/ValueTracking.h"
32 #include "llvm/IR/DataLayout.h"
33 #include "llvm/IR/Dominators.h"
34 #include "llvm/IR/IRBuilder.h"
35 #include "llvm/IR/Instructions.h"
36 #include "llvm/IR/IntrinsicInst.h"
37 #include "llvm/IR/Module.h"
38 #include "llvm/IR/NoFolder.h"
39 #include "llvm/IR/Type.h"
40 #include "llvm/IR/Value.h"
41 #include "llvm/IR/Verifier.h"
42 #include "llvm/Pass.h"
43 #include "llvm/Support/CommandLine.h"
44 #include "llvm/Support/Debug.h"
45 #include "llvm/Support/raw_ostream.h"
46 #include "llvm/Analysis/VectorUtils.h"
53 #define SV_NAME "slp-vectorizer"
54 #define DEBUG_TYPE "SLP"
56 STATISTIC(NumVectorInstructions, "Number of vector instructions generated");
59 SLPCostThreshold("slp-threshold", cl::init(0), cl::Hidden,
60 cl::desc("Only vectorize if you gain more than this "
64 ShouldVectorizeHor("slp-vectorize-hor", cl::init(false), cl::Hidden,
65 cl::desc("Attempt to vectorize horizontal reductions"));
67 static cl::opt<bool> ShouldStartVectorizeHorAtStore(
68 "slp-vectorize-hor-store", cl::init(false), cl::Hidden,
70 "Attempt to vectorize horizontal reductions feeding into a store"));
73 MaxVectorRegSizeOption("slp-max-reg-size", cl::init(128), cl::Hidden,
74 cl::desc("Attempt to vectorize for this register size in bits"));
76 /// Limits the size of scheduling regions in a block.
77 /// It avoid long compile times for _very_ large blocks where vector
78 /// instructions are spread over a wide range.
79 /// This limit is way higher than needed by real-world functions.
81 ScheduleRegionSizeBudget("slp-schedule-budget", cl::init(100000), cl::Hidden,
82 cl::desc("Limit the size of the SLP scheduling region per block"));
86 // FIXME: Set this via cl::opt to allow overriding.
87 static const unsigned MinVecRegSize = 128;
89 static const unsigned RecursionMaxDepth = 12;
91 // Limit the number of alias checks. The limit is chosen so that
92 // it has no negative effect on the llvm benchmarks.
93 static const unsigned AliasedCheckLimit = 10;
95 // Another limit for the alias checks: The maximum distance between load/store
96 // instructions where alias checks are done.
97 // This limit is useful for very large basic blocks.
98 static const unsigned MaxMemDepDistance = 160;
100 /// If the ScheduleRegionSizeBudget is exhausted, we allow small scheduling
101 /// regions to be handled.
102 static const int MinScheduleRegionSize = 16;
104 /// \brief Predicate for the element types that the SLP vectorizer supports.
106 /// The most important thing to filter here are types which are invalid in LLVM
107 /// vectors. We also filter target specific types which have absolutely no
108 /// meaningful vectorization path such as x86_fp80 and ppc_f128. This just
109 /// avoids spending time checking the cost model and realizing that they will
110 /// be inevitably scalarized.
111 static bool isValidElementType(Type *Ty) {
112 return VectorType::isValidElementType(Ty) && !Ty->isX86_FP80Ty() &&
113 !Ty->isPPC_FP128Ty();
116 /// \returns the parent basic block if all of the instructions in \p VL
117 /// are in the same block or null otherwise.
118 static BasicBlock *getSameBlock(ArrayRef<Value *> VL) {
119 Instruction *I0 = dyn_cast<Instruction>(VL[0]);
122 BasicBlock *BB = I0->getParent();
123 for (int i = 1, e = VL.size(); i < e; i++) {
124 Instruction *I = dyn_cast<Instruction>(VL[i]);
128 if (BB != I->getParent())
134 /// \returns True if all of the values in \p VL are constants.
135 static bool allConstant(ArrayRef<Value *> VL) {
136 for (unsigned i = 0, e = VL.size(); i < e; ++i)
137 if (!isa<Constant>(VL[i]))
142 /// \returns True if all of the values in \p VL are identical.
143 static bool isSplat(ArrayRef<Value *> VL) {
144 for (unsigned i = 1, e = VL.size(); i < e; ++i)
150 ///\returns Opcode that can be clubbed with \p Op to create an alternate
151 /// sequence which can later be merged as a ShuffleVector instruction.
152 static unsigned getAltOpcode(unsigned Op) {
154 case Instruction::FAdd:
155 return Instruction::FSub;
156 case Instruction::FSub:
157 return Instruction::FAdd;
158 case Instruction::Add:
159 return Instruction::Sub;
160 case Instruction::Sub:
161 return Instruction::Add;
167 ///\returns bool representing if Opcode \p Op can be part
168 /// of an alternate sequence which can later be merged as
169 /// a ShuffleVector instruction.
170 static bool canCombineAsAltInst(unsigned Op) {
171 if (Op == Instruction::FAdd || Op == Instruction::FSub ||
172 Op == Instruction::Sub || Op == Instruction::Add)
177 /// \returns ShuffleVector instruction if instructions in \p VL have
178 /// alternate fadd,fsub / fsub,fadd/add,sub/sub,add sequence.
179 /// (i.e. e.g. opcodes of fadd,fsub,fadd,fsub...)
180 static unsigned isAltInst(ArrayRef<Value *> VL) {
181 Instruction *I0 = dyn_cast<Instruction>(VL[0]);
182 unsigned Opcode = I0->getOpcode();
183 unsigned AltOpcode = getAltOpcode(Opcode);
184 for (int i = 1, e = VL.size(); i < e; i++) {
185 Instruction *I = dyn_cast<Instruction>(VL[i]);
186 if (!I || I->getOpcode() != ((i & 1) ? AltOpcode : Opcode))
189 return Instruction::ShuffleVector;
192 /// \returns The opcode if all of the Instructions in \p VL have the same
194 static unsigned getSameOpcode(ArrayRef<Value *> VL) {
195 Instruction *I0 = dyn_cast<Instruction>(VL[0]);
198 unsigned Opcode = I0->getOpcode();
199 for (int i = 1, e = VL.size(); i < e; i++) {
200 Instruction *I = dyn_cast<Instruction>(VL[i]);
201 if (!I || Opcode != I->getOpcode()) {
202 if (canCombineAsAltInst(Opcode) && i == 1)
203 return isAltInst(VL);
210 /// Get the intersection (logical and) of all of the potential IR flags
211 /// of each scalar operation (VL) that will be converted into a vector (I).
212 /// Flag set: NSW, NUW, exact, and all of fast-math.
213 static void propagateIRFlags(Value *I, ArrayRef<Value *> VL) {
214 if (auto *VecOp = dyn_cast<BinaryOperator>(I)) {
215 if (auto *Intersection = dyn_cast<BinaryOperator>(VL[0])) {
216 // Intersection is initialized to the 0th scalar,
217 // so start counting from index '1'.
218 for (int i = 1, e = VL.size(); i < e; ++i) {
219 if (auto *Scalar = dyn_cast<BinaryOperator>(VL[i]))
220 Intersection->andIRFlags(Scalar);
222 VecOp->copyIRFlags(Intersection);
227 /// \returns \p I after propagating metadata from \p VL.
228 static Instruction *propagateMetadata(Instruction *I, ArrayRef<Value *> VL) {
229 Instruction *I0 = cast<Instruction>(VL[0]);
230 SmallVector<std::pair<unsigned, MDNode *>, 4> Metadata;
231 I0->getAllMetadataOtherThanDebugLoc(Metadata);
233 for (unsigned i = 0, n = Metadata.size(); i != n; ++i) {
234 unsigned Kind = Metadata[i].first;
235 MDNode *MD = Metadata[i].second;
237 for (int i = 1, e = VL.size(); MD && i != e; i++) {
238 Instruction *I = cast<Instruction>(VL[i]);
239 MDNode *IMD = I->getMetadata(Kind);
243 MD = nullptr; // Remove unknown metadata
245 case LLVMContext::MD_tbaa:
246 MD = MDNode::getMostGenericTBAA(MD, IMD);
248 case LLVMContext::MD_alias_scope:
249 MD = MDNode::getMostGenericAliasScope(MD, IMD);
251 case LLVMContext::MD_noalias:
252 MD = MDNode::intersect(MD, IMD);
254 case LLVMContext::MD_fpmath:
255 MD = MDNode::getMostGenericFPMath(MD, IMD);
257 case LLVMContext::MD_nontemporal:
258 MD = MDNode::intersect(MD, IMD);
262 I->setMetadata(Kind, MD);
267 /// \returns The type that all of the values in \p VL have or null if there
268 /// are different types.
269 static Type* getSameType(ArrayRef<Value *> VL) {
270 Type *Ty = VL[0]->getType();
271 for (int i = 1, e = VL.size(); i < e; i++)
272 if (VL[i]->getType() != Ty)
278 /// \returns True if the ExtractElement instructions in VL can be vectorized
279 /// to use the original vector.
280 static bool CanReuseExtract(ArrayRef<Value *> VL) {
281 assert(Instruction::ExtractElement == getSameOpcode(VL) && "Invalid opcode");
282 // Check if all of the extracts come from the same vector and from the
285 ExtractElementInst *E0 = cast<ExtractElementInst>(VL0);
286 Value *Vec = E0->getOperand(0);
288 // We have to extract from the same vector type.
289 unsigned NElts = Vec->getType()->getVectorNumElements();
291 if (NElts != VL.size())
294 // Check that all of the indices extract from the correct offset.
295 ConstantInt *CI = dyn_cast<ConstantInt>(E0->getOperand(1));
296 if (!CI || CI->getZExtValue())
299 for (unsigned i = 1, e = VL.size(); i < e; ++i) {
300 ExtractElementInst *E = cast<ExtractElementInst>(VL[i]);
301 ConstantInt *CI = dyn_cast<ConstantInt>(E->getOperand(1));
303 if (!CI || CI->getZExtValue() != i || E->getOperand(0) != Vec)
310 /// \returns True if in-tree use also needs extract. This refers to
311 /// possible scalar operand in vectorized instruction.
312 static bool InTreeUserNeedToExtract(Value *Scalar, Instruction *UserInst,
313 TargetLibraryInfo *TLI) {
315 unsigned Opcode = UserInst->getOpcode();
317 case Instruction::Load: {
318 LoadInst *LI = cast<LoadInst>(UserInst);
319 return (LI->getPointerOperand() == Scalar);
321 case Instruction::Store: {
322 StoreInst *SI = cast<StoreInst>(UserInst);
323 return (SI->getPointerOperand() == Scalar);
325 case Instruction::Call: {
326 CallInst *CI = cast<CallInst>(UserInst);
327 Intrinsic::ID ID = getIntrinsicIDForCall(CI, TLI);
328 if (hasVectorInstrinsicScalarOpd(ID, 1)) {
329 return (CI->getArgOperand(1) == Scalar);
337 /// \returns the AA location that is being access by the instruction.
338 static MemoryLocation getLocation(Instruction *I, AliasAnalysis *AA) {
339 if (StoreInst *SI = dyn_cast<StoreInst>(I))
340 return MemoryLocation::get(SI);
341 if (LoadInst *LI = dyn_cast<LoadInst>(I))
342 return MemoryLocation::get(LI);
343 return MemoryLocation();
346 /// \returns True if the instruction is not a volatile or atomic load/store.
347 static bool isSimple(Instruction *I) {
348 if (LoadInst *LI = dyn_cast<LoadInst>(I))
349 return LI->isSimple();
350 if (StoreInst *SI = dyn_cast<StoreInst>(I))
351 return SI->isSimple();
352 if (MemIntrinsic *MI = dyn_cast<MemIntrinsic>(I))
353 return !MI->isVolatile();
357 /// Bottom Up SLP Vectorizer.
360 typedef SmallVector<Value *, 8> ValueList;
361 typedef SmallVector<Instruction *, 16> InstrList;
362 typedef SmallPtrSet<Value *, 16> ValueSet;
363 typedef SmallVector<StoreInst *, 8> StoreList;
365 BoUpSLP(Function *Func, ScalarEvolution *Se, TargetTransformInfo *Tti,
366 TargetLibraryInfo *TLi, AliasAnalysis *Aa, LoopInfo *Li,
367 DominatorTree *Dt, AssumptionCache *AC)
368 : NumLoadsWantToKeepOrder(0), NumLoadsWantToChangeOrder(0), F(Func),
369 SE(Se), TTI(Tti), TLI(TLi), AA(Aa), LI(Li), DT(Dt),
370 Builder(Se->getContext()) {
371 CodeMetrics::collectEphemeralValues(F, AC, EphValues);
374 /// \brief Vectorize the tree that starts with the elements in \p VL.
375 /// Returns the vectorized root.
376 Value *vectorizeTree();
378 /// \returns the cost incurred by unwanted spills and fills, caused by
379 /// holding live values over call sites.
382 /// \returns the vectorization cost of the subtree that starts at \p VL.
383 /// A negative number means that this is profitable.
386 /// Construct a vectorizable tree that starts at \p Roots, ignoring users for
387 /// the purpose of scheduling and extraction in the \p UserIgnoreLst.
388 void buildTree(ArrayRef<Value *> Roots,
389 ArrayRef<Value *> UserIgnoreLst = None);
391 /// Clear the internal data structures that are created by 'buildTree'.
393 VectorizableTree.clear();
394 ScalarToTreeEntry.clear();
396 ExternalUses.clear();
397 NumLoadsWantToKeepOrder = 0;
398 NumLoadsWantToChangeOrder = 0;
399 for (auto &Iter : BlocksSchedules) {
400 BlockScheduling *BS = Iter.second.get();
405 /// \returns true if the memory operations A and B are consecutive.
406 bool isConsecutiveAccess(Value *A, Value *B, const DataLayout &DL);
408 /// \brief Perform LICM and CSE on the newly generated gather sequences.
409 void optimizeGatherSequence();
411 /// \returns true if it is beneficial to reverse the vector order.
412 bool shouldReorder() const {
413 return NumLoadsWantToChangeOrder > NumLoadsWantToKeepOrder;
419 /// \returns the cost of the vectorizable entry.
420 int getEntryCost(TreeEntry *E);
422 /// This is the recursive part of buildTree.
423 void buildTree_rec(ArrayRef<Value *> Roots, unsigned Depth);
425 /// Vectorize a single entry in the tree.
426 Value *vectorizeTree(TreeEntry *E);
428 /// Vectorize a single entry in the tree, starting in \p VL.
429 Value *vectorizeTree(ArrayRef<Value *> VL);
431 /// \returns the pointer to the vectorized value if \p VL is already
432 /// vectorized, or NULL. They may happen in cycles.
433 Value *alreadyVectorized(ArrayRef<Value *> VL) const;
435 /// \brief Take the pointer operand from the Load/Store instruction.
436 /// \returns NULL if this is not a valid Load/Store instruction.
437 static Value *getPointerOperand(Value *I);
439 /// \brief Take the address space operand from the Load/Store instruction.
440 /// \returns -1 if this is not a valid Load/Store instruction.
441 static unsigned getAddressSpaceOperand(Value *I);
443 /// \returns the scalarization cost for this type. Scalarization in this
444 /// context means the creation of vectors from a group of scalars.
445 int getGatherCost(Type *Ty);
447 /// \returns the scalarization cost for this list of values. Assuming that
448 /// this subtree gets vectorized, we may need to extract the values from the
449 /// roots. This method calculates the cost of extracting the values.
450 int getGatherCost(ArrayRef<Value *> VL);
452 /// \brief Set the Builder insert point to one after the last instruction in
454 void setInsertPointAfterBundle(ArrayRef<Value *> VL);
456 /// \returns a vector from a collection of scalars in \p VL.
457 Value *Gather(ArrayRef<Value *> VL, VectorType *Ty);
459 /// \returns whether the VectorizableTree is fully vectorizable and will
460 /// be beneficial even the tree height is tiny.
461 bool isFullyVectorizableTinyTree();
463 /// \reorder commutative operands in alt shuffle if they result in
465 void reorderAltShuffleOperands(ArrayRef<Value *> VL,
466 SmallVectorImpl<Value *> &Left,
467 SmallVectorImpl<Value *> &Right);
468 /// \reorder commutative operands to get better probability of
469 /// generating vectorized code.
470 void reorderInputsAccordingToOpcode(ArrayRef<Value *> VL,
471 SmallVectorImpl<Value *> &Left,
472 SmallVectorImpl<Value *> &Right);
474 TreeEntry() : Scalars(), VectorizedValue(nullptr),
477 /// \returns true if the scalars in VL are equal to this entry.
478 bool isSame(ArrayRef<Value *> VL) const {
479 assert(VL.size() == Scalars.size() && "Invalid size");
480 return std::equal(VL.begin(), VL.end(), Scalars.begin());
483 /// A vector of scalars.
486 /// The Scalars are vectorized into this value. It is initialized to Null.
487 Value *VectorizedValue;
489 /// Do we need to gather this sequence ?
493 /// Create a new VectorizableTree entry.
494 TreeEntry *newTreeEntry(ArrayRef<Value *> VL, bool Vectorized) {
495 VectorizableTree.emplace_back();
496 int idx = VectorizableTree.size() - 1;
497 TreeEntry *Last = &VectorizableTree[idx];
498 Last->Scalars.insert(Last->Scalars.begin(), VL.begin(), VL.end());
499 Last->NeedToGather = !Vectorized;
501 for (int i = 0, e = VL.size(); i != e; ++i) {
502 assert(!ScalarToTreeEntry.count(VL[i]) && "Scalar already in tree!");
503 ScalarToTreeEntry[VL[i]] = idx;
506 MustGather.insert(VL.begin(), VL.end());
511 /// -- Vectorization State --
512 /// Holds all of the tree entries.
513 std::vector<TreeEntry> VectorizableTree;
515 /// Maps a specific scalar to its tree entry.
516 SmallDenseMap<Value*, int> ScalarToTreeEntry;
518 /// A list of scalars that we found that we need to keep as scalars.
521 /// This POD struct describes one external user in the vectorized tree.
522 struct ExternalUser {
523 ExternalUser (Value *S, llvm::User *U, int L) :
524 Scalar(S), User(U), Lane(L){}
525 // Which scalar in our function.
527 // Which user that uses the scalar.
529 // Which lane does the scalar belong to.
532 typedef SmallVector<ExternalUser, 16> UserList;
534 /// Checks if two instructions may access the same memory.
536 /// \p Loc1 is the location of \p Inst1. It is passed explicitly because it
537 /// is invariant in the calling loop.
538 bool isAliased(const MemoryLocation &Loc1, Instruction *Inst1,
539 Instruction *Inst2) {
541 // First check if the result is already in the cache.
542 AliasCacheKey key = std::make_pair(Inst1, Inst2);
543 Optional<bool> &result = AliasCache[key];
544 if (result.hasValue()) {
545 return result.getValue();
547 MemoryLocation Loc2 = getLocation(Inst2, AA);
549 if (Loc1.Ptr && Loc2.Ptr && isSimple(Inst1) && isSimple(Inst2)) {
550 // Do the alias check.
551 aliased = AA->alias(Loc1, Loc2);
553 // Store the result in the cache.
558 typedef std::pair<Instruction *, Instruction *> AliasCacheKey;
560 /// Cache for alias results.
561 /// TODO: consider moving this to the AliasAnalysis itself.
562 DenseMap<AliasCacheKey, Optional<bool>> AliasCache;
564 /// Removes an instruction from its block and eventually deletes it.
565 /// It's like Instruction::eraseFromParent() except that the actual deletion
566 /// is delayed until BoUpSLP is destructed.
567 /// This is required to ensure that there are no incorrect collisions in the
568 /// AliasCache, which can happen if a new instruction is allocated at the
569 /// same address as a previously deleted instruction.
570 void eraseInstruction(Instruction *I) {
571 I->removeFromParent();
572 I->dropAllReferences();
573 DeletedInstructions.push_back(std::unique_ptr<Instruction>(I));
576 /// Temporary store for deleted instructions. Instructions will be deleted
577 /// eventually when the BoUpSLP is destructed.
578 SmallVector<std::unique_ptr<Instruction>, 8> DeletedInstructions;
580 /// A list of values that need to extracted out of the tree.
581 /// This list holds pairs of (Internal Scalar : External User).
582 UserList ExternalUses;
584 /// Values used only by @llvm.assume calls.
585 SmallPtrSet<const Value *, 32> EphValues;
587 /// Holds all of the instructions that we gathered.
588 SetVector<Instruction *> GatherSeq;
589 /// A list of blocks that we are going to CSE.
590 SetVector<BasicBlock *> CSEBlocks;
592 /// Contains all scheduling relevant data for an instruction.
593 /// A ScheduleData either represents a single instruction or a member of an
594 /// instruction bundle (= a group of instructions which is combined into a
595 /// vector instruction).
596 struct ScheduleData {
598 // The initial value for the dependency counters. It means that the
599 // dependencies are not calculated yet.
600 enum { InvalidDeps = -1 };
603 : Inst(nullptr), FirstInBundle(nullptr), NextInBundle(nullptr),
604 NextLoadStore(nullptr), SchedulingRegionID(0), SchedulingPriority(0),
605 Dependencies(InvalidDeps), UnscheduledDeps(InvalidDeps),
606 UnscheduledDepsInBundle(InvalidDeps), IsScheduled(false) {}
608 void init(int BlockSchedulingRegionID) {
609 FirstInBundle = this;
610 NextInBundle = nullptr;
611 NextLoadStore = nullptr;
613 SchedulingRegionID = BlockSchedulingRegionID;
614 UnscheduledDepsInBundle = UnscheduledDeps;
618 /// Returns true if the dependency information has been calculated.
619 bool hasValidDependencies() const { return Dependencies != InvalidDeps; }
621 /// Returns true for single instructions and for bundle representatives
622 /// (= the head of a bundle).
623 bool isSchedulingEntity() const { return FirstInBundle == this; }
625 /// Returns true if it represents an instruction bundle and not only a
626 /// single instruction.
627 bool isPartOfBundle() const {
628 return NextInBundle != nullptr || FirstInBundle != this;
631 /// Returns true if it is ready for scheduling, i.e. it has no more
632 /// unscheduled depending instructions/bundles.
633 bool isReady() const {
634 assert(isSchedulingEntity() &&
635 "can't consider non-scheduling entity for ready list");
636 return UnscheduledDepsInBundle == 0 && !IsScheduled;
639 /// Modifies the number of unscheduled dependencies, also updating it for
640 /// the whole bundle.
641 int incrementUnscheduledDeps(int Incr) {
642 UnscheduledDeps += Incr;
643 return FirstInBundle->UnscheduledDepsInBundle += Incr;
646 /// Sets the number of unscheduled dependencies to the number of
648 void resetUnscheduledDeps() {
649 incrementUnscheduledDeps(Dependencies - UnscheduledDeps);
652 /// Clears all dependency information.
653 void clearDependencies() {
654 Dependencies = InvalidDeps;
655 resetUnscheduledDeps();
656 MemoryDependencies.clear();
659 void dump(raw_ostream &os) const {
660 if (!isSchedulingEntity()) {
662 } else if (NextInBundle) {
664 ScheduleData *SD = NextInBundle;
666 os << ';' << *SD->Inst;
667 SD = SD->NextInBundle;
677 /// Points to the head in an instruction bundle (and always to this for
678 /// single instructions).
679 ScheduleData *FirstInBundle;
681 /// Single linked list of all instructions in a bundle. Null if it is a
682 /// single instruction.
683 ScheduleData *NextInBundle;
685 /// Single linked list of all memory instructions (e.g. load, store, call)
686 /// in the block - until the end of the scheduling region.
687 ScheduleData *NextLoadStore;
689 /// The dependent memory instructions.
690 /// This list is derived on demand in calculateDependencies().
691 SmallVector<ScheduleData *, 4> MemoryDependencies;
693 /// This ScheduleData is in the current scheduling region if this matches
694 /// the current SchedulingRegionID of BlockScheduling.
695 int SchedulingRegionID;
697 /// Used for getting a "good" final ordering of instructions.
698 int SchedulingPriority;
700 /// The number of dependencies. Constitutes of the number of users of the
701 /// instruction plus the number of dependent memory instructions (if any).
702 /// This value is calculated on demand.
703 /// If InvalidDeps, the number of dependencies is not calculated yet.
707 /// The number of dependencies minus the number of dependencies of scheduled
708 /// instructions. As soon as this is zero, the instruction/bundle gets ready
710 /// Note that this is negative as long as Dependencies is not calculated.
713 /// The sum of UnscheduledDeps in a bundle. Equals to UnscheduledDeps for
714 /// single instructions.
715 int UnscheduledDepsInBundle;
717 /// True if this instruction is scheduled (or considered as scheduled in the
723 friend raw_ostream &operator<<(raw_ostream &os,
724 const BoUpSLP::ScheduleData &SD);
727 /// Contains all scheduling data for a basic block.
729 struct BlockScheduling {
731 BlockScheduling(BasicBlock *BB)
732 : BB(BB), ChunkSize(BB->size()), ChunkPos(ChunkSize),
733 ScheduleStart(nullptr), ScheduleEnd(nullptr),
734 FirstLoadStoreInRegion(nullptr), LastLoadStoreInRegion(nullptr),
735 ScheduleRegionSize(0),
736 ScheduleRegionSizeLimit(ScheduleRegionSizeBudget),
737 // Make sure that the initial SchedulingRegionID is greater than the
738 // initial SchedulingRegionID in ScheduleData (which is 0).
739 SchedulingRegionID(1) {}
743 ScheduleStart = nullptr;
744 ScheduleEnd = nullptr;
745 FirstLoadStoreInRegion = nullptr;
746 LastLoadStoreInRegion = nullptr;
748 // Reduce the maximum schedule region size by the size of the
749 // previous scheduling run.
750 ScheduleRegionSizeLimit -= ScheduleRegionSize;
751 if (ScheduleRegionSizeLimit < MinScheduleRegionSize)
752 ScheduleRegionSizeLimit = MinScheduleRegionSize;
753 ScheduleRegionSize = 0;
755 // Make a new scheduling region, i.e. all existing ScheduleData is not
756 // in the new region yet.
757 ++SchedulingRegionID;
760 ScheduleData *getScheduleData(Value *V) {
761 ScheduleData *SD = ScheduleDataMap[V];
762 if (SD && SD->SchedulingRegionID == SchedulingRegionID)
767 bool isInSchedulingRegion(ScheduleData *SD) {
768 return SD->SchedulingRegionID == SchedulingRegionID;
771 /// Marks an instruction as scheduled and puts all dependent ready
772 /// instructions into the ready-list.
773 template <typename ReadyListType>
774 void schedule(ScheduleData *SD, ReadyListType &ReadyList) {
775 SD->IsScheduled = true;
776 DEBUG(dbgs() << "SLP: schedule " << *SD << "\n");
778 ScheduleData *BundleMember = SD;
779 while (BundleMember) {
780 // Handle the def-use chain dependencies.
781 for (Use &U : BundleMember->Inst->operands()) {
782 ScheduleData *OpDef = getScheduleData(U.get());
783 if (OpDef && OpDef->hasValidDependencies() &&
784 OpDef->incrementUnscheduledDeps(-1) == 0) {
785 // There are no more unscheduled dependencies after decrementing,
786 // so we can put the dependent instruction into the ready list.
787 ScheduleData *DepBundle = OpDef->FirstInBundle;
788 assert(!DepBundle->IsScheduled &&
789 "already scheduled bundle gets ready");
790 ReadyList.insert(DepBundle);
791 DEBUG(dbgs() << "SLP: gets ready (def): " << *DepBundle << "\n");
794 // Handle the memory dependencies.
795 for (ScheduleData *MemoryDepSD : BundleMember->MemoryDependencies) {
796 if (MemoryDepSD->incrementUnscheduledDeps(-1) == 0) {
797 // There are no more unscheduled dependencies after decrementing,
798 // so we can put the dependent instruction into the ready list.
799 ScheduleData *DepBundle = MemoryDepSD->FirstInBundle;
800 assert(!DepBundle->IsScheduled &&
801 "already scheduled bundle gets ready");
802 ReadyList.insert(DepBundle);
803 DEBUG(dbgs() << "SLP: gets ready (mem): " << *DepBundle << "\n");
806 BundleMember = BundleMember->NextInBundle;
810 /// Put all instructions into the ReadyList which are ready for scheduling.
811 template <typename ReadyListType>
812 void initialFillReadyList(ReadyListType &ReadyList) {
813 for (auto *I = ScheduleStart; I != ScheduleEnd; I = I->getNextNode()) {
814 ScheduleData *SD = getScheduleData(I);
815 if (SD->isSchedulingEntity() && SD->isReady()) {
816 ReadyList.insert(SD);
817 DEBUG(dbgs() << "SLP: initially in ready list: " << *I << "\n");
822 /// Checks if a bundle of instructions can be scheduled, i.e. has no
823 /// cyclic dependencies. This is only a dry-run, no instructions are
824 /// actually moved at this stage.
825 bool tryScheduleBundle(ArrayRef<Value *> VL, BoUpSLP *SLP);
827 /// Un-bundles a group of instructions.
828 void cancelScheduling(ArrayRef<Value *> VL);
830 /// Extends the scheduling region so that V is inside the region.
831 /// \returns true if the region size is within the limit.
832 bool extendSchedulingRegion(Value *V);
834 /// Initialize the ScheduleData structures for new instructions in the
835 /// scheduling region.
836 void initScheduleData(Instruction *FromI, Instruction *ToI,
837 ScheduleData *PrevLoadStore,
838 ScheduleData *NextLoadStore);
840 /// Updates the dependency information of a bundle and of all instructions/
841 /// bundles which depend on the original bundle.
842 void calculateDependencies(ScheduleData *SD, bool InsertInReadyList,
845 /// Sets all instruction in the scheduling region to un-scheduled.
846 void resetSchedule();
850 /// Simple memory allocation for ScheduleData.
851 std::vector<std::unique_ptr<ScheduleData[]>> ScheduleDataChunks;
853 /// The size of a ScheduleData array in ScheduleDataChunks.
856 /// The allocator position in the current chunk, which is the last entry
857 /// of ScheduleDataChunks.
860 /// Attaches ScheduleData to Instruction.
861 /// Note that the mapping survives during all vectorization iterations, i.e.
862 /// ScheduleData structures are recycled.
863 DenseMap<Value *, ScheduleData *> ScheduleDataMap;
865 struct ReadyList : SmallVector<ScheduleData *, 8> {
866 void insert(ScheduleData *SD) { push_back(SD); }
869 /// The ready-list for scheduling (only used for the dry-run).
870 ReadyList ReadyInsts;
872 /// The first instruction of the scheduling region.
873 Instruction *ScheduleStart;
875 /// The first instruction _after_ the scheduling region.
876 Instruction *ScheduleEnd;
878 /// The first memory accessing instruction in the scheduling region
880 ScheduleData *FirstLoadStoreInRegion;
882 /// The last memory accessing instruction in the scheduling region
884 ScheduleData *LastLoadStoreInRegion;
886 /// The current size of the scheduling region.
887 int ScheduleRegionSize;
889 /// The maximum size allowed for the scheduling region.
890 int ScheduleRegionSizeLimit;
892 /// The ID of the scheduling region. For a new vectorization iteration this
893 /// is incremented which "removes" all ScheduleData from the region.
894 int SchedulingRegionID;
897 /// Attaches the BlockScheduling structures to basic blocks.
898 MapVector<BasicBlock *, std::unique_ptr<BlockScheduling>> BlocksSchedules;
900 /// Performs the "real" scheduling. Done before vectorization is actually
901 /// performed in a basic block.
902 void scheduleBlock(BlockScheduling *BS);
904 /// List of users to ignore during scheduling and that don't need extracting.
905 ArrayRef<Value *> UserIgnoreList;
907 // Number of load-bundles, which contain consecutive loads.
908 int NumLoadsWantToKeepOrder;
910 // Number of load-bundles of size 2, which are consecutive loads if reversed.
911 int NumLoadsWantToChangeOrder;
913 // Analysis and block reference.
916 TargetTransformInfo *TTI;
917 TargetLibraryInfo *TLI;
921 /// Instruction builder to construct the vectorized tree.
926 raw_ostream &operator<<(raw_ostream &os, const BoUpSLP::ScheduleData &SD) {
932 void BoUpSLP::buildTree(ArrayRef<Value *> Roots,
933 ArrayRef<Value *> UserIgnoreLst) {
935 UserIgnoreList = UserIgnoreLst;
936 if (!getSameType(Roots))
938 buildTree_rec(Roots, 0);
940 // Collect the values that we need to extract from the tree.
941 for (int EIdx = 0, EE = VectorizableTree.size(); EIdx < EE; ++EIdx) {
942 TreeEntry *Entry = &VectorizableTree[EIdx];
945 for (int Lane = 0, LE = Entry->Scalars.size(); Lane != LE; ++Lane) {
946 Value *Scalar = Entry->Scalars[Lane];
948 // No need to handle users of gathered values.
949 if (Entry->NeedToGather)
952 for (User *U : Scalar->users()) {
953 DEBUG(dbgs() << "SLP: Checking user:" << *U << ".\n");
955 Instruction *UserInst = dyn_cast<Instruction>(U);
959 // Skip in-tree scalars that become vectors
960 if (ScalarToTreeEntry.count(U)) {
961 int Idx = ScalarToTreeEntry[U];
962 TreeEntry *UseEntry = &VectorizableTree[Idx];
963 Value *UseScalar = UseEntry->Scalars[0];
964 // Some in-tree scalars will remain as scalar in vectorized
965 // instructions. If that is the case, the one in Lane 0 will
967 if (UseScalar != U ||
968 !InTreeUserNeedToExtract(Scalar, UserInst, TLI)) {
969 DEBUG(dbgs() << "SLP: \tInternal user will be removed:" << *U
971 assert(!VectorizableTree[Idx].NeedToGather && "Bad state");
976 // Ignore users in the user ignore list.
977 if (std::find(UserIgnoreList.begin(), UserIgnoreList.end(), UserInst) !=
978 UserIgnoreList.end())
981 DEBUG(dbgs() << "SLP: Need to extract:" << *U << " from lane " <<
982 Lane << " from " << *Scalar << ".\n");
983 ExternalUses.push_back(ExternalUser(Scalar, U, Lane));
990 void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
991 bool SameTy = getSameType(VL); (void)SameTy;
992 bool isAltShuffle = false;
993 assert(SameTy && "Invalid types!");
995 if (Depth == RecursionMaxDepth) {
996 DEBUG(dbgs() << "SLP: Gathering due to max recursion depth.\n");
997 newTreeEntry(VL, false);
1001 // Don't handle vectors.
1002 if (VL[0]->getType()->isVectorTy()) {
1003 DEBUG(dbgs() << "SLP: Gathering due to vector type.\n");
1004 newTreeEntry(VL, false);
1008 if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
1009 if (SI->getValueOperand()->getType()->isVectorTy()) {
1010 DEBUG(dbgs() << "SLP: Gathering due to store vector type.\n");
1011 newTreeEntry(VL, false);
1014 unsigned Opcode = getSameOpcode(VL);
1016 // Check that this shuffle vector refers to the alternate
1017 // sequence of opcodes.
1018 if (Opcode == Instruction::ShuffleVector) {
1019 Instruction *I0 = dyn_cast<Instruction>(VL[0]);
1020 unsigned Op = I0->getOpcode();
1021 if (Op != Instruction::ShuffleVector)
1022 isAltShuffle = true;
1025 // If all of the operands are identical or constant we have a simple solution.
1026 if (allConstant(VL) || isSplat(VL) || !getSameBlock(VL) || !Opcode) {
1027 DEBUG(dbgs() << "SLP: Gathering due to C,S,B,O. \n");
1028 newTreeEntry(VL, false);
1032 // We now know that this is a vector of instructions of the same type from
1035 // Don't vectorize ephemeral values.
1036 for (unsigned i = 0, e = VL.size(); i != e; ++i) {
1037 if (EphValues.count(VL[i])) {
1038 DEBUG(dbgs() << "SLP: The instruction (" << *VL[i] <<
1039 ") is ephemeral.\n");
1040 newTreeEntry(VL, false);
1045 // Check if this is a duplicate of another entry.
1046 if (ScalarToTreeEntry.count(VL[0])) {
1047 int Idx = ScalarToTreeEntry[VL[0]];
1048 TreeEntry *E = &VectorizableTree[Idx];
1049 for (unsigned i = 0, e = VL.size(); i != e; ++i) {
1050 DEBUG(dbgs() << "SLP: \tChecking bundle: " << *VL[i] << ".\n");
1051 if (E->Scalars[i] != VL[i]) {
1052 DEBUG(dbgs() << "SLP: Gathering due to partial overlap.\n");
1053 newTreeEntry(VL, false);
1057 DEBUG(dbgs() << "SLP: Perfect diamond merge at " << *VL[0] << ".\n");
1061 // Check that none of the instructions in the bundle are already in the tree.
1062 for (unsigned i = 0, e = VL.size(); i != e; ++i) {
1063 if (ScalarToTreeEntry.count(VL[i])) {
1064 DEBUG(dbgs() << "SLP: The instruction (" << *VL[i] <<
1065 ") is already in tree.\n");
1066 newTreeEntry(VL, false);
1071 // If any of the scalars is marked as a value that needs to stay scalar then
1072 // we need to gather the scalars.
1073 for (unsigned i = 0, e = VL.size(); i != e; ++i) {
1074 if (MustGather.count(VL[i])) {
1075 DEBUG(dbgs() << "SLP: Gathering due to gathered scalar.\n");
1076 newTreeEntry(VL, false);
1081 // Check that all of the users of the scalars that we want to vectorize are
1083 Instruction *VL0 = cast<Instruction>(VL[0]);
1084 BasicBlock *BB = cast<Instruction>(VL0)->getParent();
1086 if (!DT->isReachableFromEntry(BB)) {
1087 // Don't go into unreachable blocks. They may contain instructions with
1088 // dependency cycles which confuse the final scheduling.
1089 DEBUG(dbgs() << "SLP: bundle in unreachable block.\n");
1090 newTreeEntry(VL, false);
1094 // Check that every instructions appears once in this bundle.
1095 for (unsigned i = 0, e = VL.size(); i < e; ++i)
1096 for (unsigned j = i+1; j < e; ++j)
1097 if (VL[i] == VL[j]) {
1098 DEBUG(dbgs() << "SLP: Scalar used twice in bundle.\n");
1099 newTreeEntry(VL, false);
1103 auto &BSRef = BlocksSchedules[BB];
1105 BSRef = llvm::make_unique<BlockScheduling>(BB);
1107 BlockScheduling &BS = *BSRef.get();
1109 if (!BS.tryScheduleBundle(VL, this)) {
1110 DEBUG(dbgs() << "SLP: We are not able to schedule this bundle!\n");
1111 assert((!BS.getScheduleData(VL[0]) ||
1112 !BS.getScheduleData(VL[0])->isPartOfBundle()) &&
1113 "tryScheduleBundle should cancelScheduling on failure");
1114 newTreeEntry(VL, false);
1117 DEBUG(dbgs() << "SLP: We are able to schedule this bundle.\n");
1120 case Instruction::PHI: {
1121 PHINode *PH = dyn_cast<PHINode>(VL0);
1123 // Check for terminator values (e.g. invoke).
1124 for (unsigned j = 0; j < VL.size(); ++j)
1125 for (unsigned i = 0, e = PH->getNumIncomingValues(); i < e; ++i) {
1126 TerminatorInst *Term = dyn_cast<TerminatorInst>(
1127 cast<PHINode>(VL[j])->getIncomingValueForBlock(PH->getIncomingBlock(i)));
1129 DEBUG(dbgs() << "SLP: Need to swizzle PHINodes (TerminatorInst use).\n");
1130 BS.cancelScheduling(VL);
1131 newTreeEntry(VL, false);
1136 newTreeEntry(VL, true);
1137 DEBUG(dbgs() << "SLP: added a vector of PHINodes.\n");
1139 for (unsigned i = 0, e = PH->getNumIncomingValues(); i < e; ++i) {
1141 // Prepare the operand vector.
1142 for (unsigned j = 0; j < VL.size(); ++j)
1143 Operands.push_back(cast<PHINode>(VL[j])->getIncomingValueForBlock(
1144 PH->getIncomingBlock(i)));
1146 buildTree_rec(Operands, Depth + 1);
1150 case Instruction::ExtractElement: {
1151 bool Reuse = CanReuseExtract(VL);
1153 DEBUG(dbgs() << "SLP: Reusing extract sequence.\n");
1155 BS.cancelScheduling(VL);
1157 newTreeEntry(VL, Reuse);
1160 case Instruction::Load: {
1161 // Check if the loads are consecutive or of we need to swizzle them.
1162 for (unsigned i = 0, e = VL.size() - 1; i < e; ++i) {
1163 LoadInst *L = cast<LoadInst>(VL[i]);
1164 if (!L->isSimple()) {
1165 BS.cancelScheduling(VL);
1166 newTreeEntry(VL, false);
1167 DEBUG(dbgs() << "SLP: Gathering non-simple loads.\n");
1170 const DataLayout &DL = F->getParent()->getDataLayout();
1171 if (!isConsecutiveAccess(VL[i], VL[i + 1], DL)) {
1172 if (VL.size() == 2 && isConsecutiveAccess(VL[1], VL[0], DL)) {
1173 ++NumLoadsWantToChangeOrder;
1175 BS.cancelScheduling(VL);
1176 newTreeEntry(VL, false);
1177 DEBUG(dbgs() << "SLP: Gathering non-consecutive loads.\n");
1181 ++NumLoadsWantToKeepOrder;
1182 newTreeEntry(VL, true);
1183 DEBUG(dbgs() << "SLP: added a vector of loads.\n");
1186 case Instruction::ZExt:
1187 case Instruction::SExt:
1188 case Instruction::FPToUI:
1189 case Instruction::FPToSI:
1190 case Instruction::FPExt:
1191 case Instruction::PtrToInt:
1192 case Instruction::IntToPtr:
1193 case Instruction::SIToFP:
1194 case Instruction::UIToFP:
1195 case Instruction::Trunc:
1196 case Instruction::FPTrunc:
1197 case Instruction::BitCast: {
1198 Type *SrcTy = VL0->getOperand(0)->getType();
1199 for (unsigned i = 0; i < VL.size(); ++i) {
1200 Type *Ty = cast<Instruction>(VL[i])->getOperand(0)->getType();
1201 if (Ty != SrcTy || !isValidElementType(Ty)) {
1202 BS.cancelScheduling(VL);
1203 newTreeEntry(VL, false);
1204 DEBUG(dbgs() << "SLP: Gathering casts with different src types.\n");
1208 newTreeEntry(VL, true);
1209 DEBUG(dbgs() << "SLP: added a vector of casts.\n");
1211 for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
1213 // Prepare the operand vector.
1214 for (unsigned j = 0; j < VL.size(); ++j)
1215 Operands.push_back(cast<Instruction>(VL[j])->getOperand(i));
1217 buildTree_rec(Operands, Depth+1);
1221 case Instruction::ICmp:
1222 case Instruction::FCmp: {
1223 // Check that all of the compares have the same predicate.
1224 CmpInst::Predicate P0 = cast<CmpInst>(VL0)->getPredicate();
1225 Type *ComparedTy = cast<Instruction>(VL[0])->getOperand(0)->getType();
1226 for (unsigned i = 1, e = VL.size(); i < e; ++i) {
1227 CmpInst *Cmp = cast<CmpInst>(VL[i]);
1228 if (Cmp->getPredicate() != P0 ||
1229 Cmp->getOperand(0)->getType() != ComparedTy) {
1230 BS.cancelScheduling(VL);
1231 newTreeEntry(VL, false);
1232 DEBUG(dbgs() << "SLP: Gathering cmp with different predicate.\n");
1237 newTreeEntry(VL, true);
1238 DEBUG(dbgs() << "SLP: added a vector of compares.\n");
1240 for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
1242 // Prepare the operand vector.
1243 for (unsigned j = 0; j < VL.size(); ++j)
1244 Operands.push_back(cast<Instruction>(VL[j])->getOperand(i));
1246 buildTree_rec(Operands, Depth+1);
1250 case Instruction::Select:
1251 case Instruction::Add:
1252 case Instruction::FAdd:
1253 case Instruction::Sub:
1254 case Instruction::FSub:
1255 case Instruction::Mul:
1256 case Instruction::FMul:
1257 case Instruction::UDiv:
1258 case Instruction::SDiv:
1259 case Instruction::FDiv:
1260 case Instruction::URem:
1261 case Instruction::SRem:
1262 case Instruction::FRem:
1263 case Instruction::Shl:
1264 case Instruction::LShr:
1265 case Instruction::AShr:
1266 case Instruction::And:
1267 case Instruction::Or:
1268 case Instruction::Xor: {
1269 newTreeEntry(VL, true);
1270 DEBUG(dbgs() << "SLP: added a vector of bin op.\n");
1272 // Sort operands of the instructions so that each side is more likely to
1273 // have the same opcode.
1274 if (isa<BinaryOperator>(VL0) && VL0->isCommutative()) {
1275 ValueList Left, Right;
1276 reorderInputsAccordingToOpcode(VL, Left, Right);
1277 buildTree_rec(Left, Depth + 1);
1278 buildTree_rec(Right, Depth + 1);
1282 for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
1284 // Prepare the operand vector.
1285 for (unsigned j = 0; j < VL.size(); ++j)
1286 Operands.push_back(cast<Instruction>(VL[j])->getOperand(i));
1288 buildTree_rec(Operands, Depth+1);
1292 case Instruction::GetElementPtr: {
1293 // We don't combine GEPs with complicated (nested) indexing.
1294 for (unsigned j = 0; j < VL.size(); ++j) {
1295 if (cast<Instruction>(VL[j])->getNumOperands() != 2) {
1296 DEBUG(dbgs() << "SLP: not-vectorizable GEP (nested indexes).\n");
1297 BS.cancelScheduling(VL);
1298 newTreeEntry(VL, false);
1303 // We can't combine several GEPs into one vector if they operate on
1305 Type *Ty0 = cast<Instruction>(VL0)->getOperand(0)->getType();
1306 for (unsigned j = 0; j < VL.size(); ++j) {
1307 Type *CurTy = cast<Instruction>(VL[j])->getOperand(0)->getType();
1309 DEBUG(dbgs() << "SLP: not-vectorizable GEP (different types).\n");
1310 BS.cancelScheduling(VL);
1311 newTreeEntry(VL, false);
1316 // We don't combine GEPs with non-constant indexes.
1317 for (unsigned j = 0; j < VL.size(); ++j) {
1318 auto Op = cast<Instruction>(VL[j])->getOperand(1);
1319 if (!isa<ConstantInt>(Op)) {
1321 dbgs() << "SLP: not-vectorizable GEP (non-constant indexes).\n");
1322 BS.cancelScheduling(VL);
1323 newTreeEntry(VL, false);
1328 newTreeEntry(VL, true);
1329 DEBUG(dbgs() << "SLP: added a vector of GEPs.\n");
1330 for (unsigned i = 0, e = 2; i < e; ++i) {
1332 // Prepare the operand vector.
1333 for (unsigned j = 0; j < VL.size(); ++j)
1334 Operands.push_back(cast<Instruction>(VL[j])->getOperand(i));
1336 buildTree_rec(Operands, Depth + 1);
1340 case Instruction::Store: {
1341 const DataLayout &DL = F->getParent()->getDataLayout();
1342 // Check if the stores are consecutive or of we need to swizzle them.
1343 for (unsigned i = 0, e = VL.size() - 1; i < e; ++i)
1344 if (!isConsecutiveAccess(VL[i], VL[i + 1], DL)) {
1345 BS.cancelScheduling(VL);
1346 newTreeEntry(VL, false);
1347 DEBUG(dbgs() << "SLP: Non-consecutive store.\n");
1351 newTreeEntry(VL, true);
1352 DEBUG(dbgs() << "SLP: added a vector of stores.\n");
1355 for (unsigned j = 0; j < VL.size(); ++j)
1356 Operands.push_back(cast<Instruction>(VL[j])->getOperand(0));
1358 buildTree_rec(Operands, Depth + 1);
1361 case Instruction::Call: {
1362 // Check if the calls are all to the same vectorizable intrinsic.
1363 CallInst *CI = cast<CallInst>(VL[0]);
1364 // Check if this is an Intrinsic call or something that can be
1365 // represented by an intrinsic call
1366 Intrinsic::ID ID = getIntrinsicIDForCall(CI, TLI);
1367 if (!isTriviallyVectorizable(ID)) {
1368 BS.cancelScheduling(VL);
1369 newTreeEntry(VL, false);
1370 DEBUG(dbgs() << "SLP: Non-vectorizable call.\n");
1373 Function *Int = CI->getCalledFunction();
1374 Value *A1I = nullptr;
1375 if (hasVectorInstrinsicScalarOpd(ID, 1))
1376 A1I = CI->getArgOperand(1);
1377 for (unsigned i = 1, e = VL.size(); i != e; ++i) {
1378 CallInst *CI2 = dyn_cast<CallInst>(VL[i]);
1379 if (!CI2 || CI2->getCalledFunction() != Int ||
1380 getIntrinsicIDForCall(CI2, TLI) != ID) {
1381 BS.cancelScheduling(VL);
1382 newTreeEntry(VL, false);
1383 DEBUG(dbgs() << "SLP: mismatched calls:" << *CI << "!=" << *VL[i]
1387 // ctlz,cttz and powi are special intrinsics whose second argument
1388 // should be same in order for them to be vectorized.
1389 if (hasVectorInstrinsicScalarOpd(ID, 1)) {
1390 Value *A1J = CI2->getArgOperand(1);
1392 BS.cancelScheduling(VL);
1393 newTreeEntry(VL, false);
1394 DEBUG(dbgs() << "SLP: mismatched arguments in call:" << *CI
1395 << " argument "<< A1I<<"!=" << A1J
1402 newTreeEntry(VL, true);
1403 for (unsigned i = 0, e = CI->getNumArgOperands(); i != e; ++i) {
1405 // Prepare the operand vector.
1406 for (unsigned j = 0; j < VL.size(); ++j) {
1407 CallInst *CI2 = dyn_cast<CallInst>(VL[j]);
1408 Operands.push_back(CI2->getArgOperand(i));
1410 buildTree_rec(Operands, Depth + 1);
1414 case Instruction::ShuffleVector: {
1415 // If this is not an alternate sequence of opcode like add-sub
1416 // then do not vectorize this instruction.
1417 if (!isAltShuffle) {
1418 BS.cancelScheduling(VL);
1419 newTreeEntry(VL, false);
1420 DEBUG(dbgs() << "SLP: ShuffleVector are not vectorized.\n");
1423 newTreeEntry(VL, true);
1424 DEBUG(dbgs() << "SLP: added a ShuffleVector op.\n");
1426 // Reorder operands if reordering would enable vectorization.
1427 if (isa<BinaryOperator>(VL0)) {
1428 ValueList Left, Right;
1429 reorderAltShuffleOperands(VL, Left, Right);
1430 buildTree_rec(Left, Depth + 1);
1431 buildTree_rec(Right, Depth + 1);
1435 for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
1437 // Prepare the operand vector.
1438 for (unsigned j = 0; j < VL.size(); ++j)
1439 Operands.push_back(cast<Instruction>(VL[j])->getOperand(i));
1441 buildTree_rec(Operands, Depth + 1);
1446 BS.cancelScheduling(VL);
1447 newTreeEntry(VL, false);
1448 DEBUG(dbgs() << "SLP: Gathering unknown instruction.\n");
1453 int BoUpSLP::getEntryCost(TreeEntry *E) {
1454 ArrayRef<Value*> VL = E->Scalars;
1456 Type *ScalarTy = VL[0]->getType();
1457 if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
1458 ScalarTy = SI->getValueOperand()->getType();
1459 VectorType *VecTy = VectorType::get(ScalarTy, VL.size());
1461 if (E->NeedToGather) {
1462 if (allConstant(VL))
1465 return TTI->getShuffleCost(TargetTransformInfo::SK_Broadcast, VecTy, 0);
1467 return getGatherCost(E->Scalars);
1469 unsigned Opcode = getSameOpcode(VL);
1470 assert(Opcode && getSameType(VL) && getSameBlock(VL) && "Invalid VL");
1471 Instruction *VL0 = cast<Instruction>(VL[0]);
1473 case Instruction::PHI: {
1476 case Instruction::ExtractElement: {
1477 if (CanReuseExtract(VL)) {
1479 for (unsigned i = 0, e = VL.size(); i < e; ++i) {
1480 ExtractElementInst *E = cast<ExtractElementInst>(VL[i]);
1482 // Take credit for instruction that will become dead.
1484 TTI->getVectorInstrCost(Instruction::ExtractElement, VecTy, i);
1488 return getGatherCost(VecTy);
1490 case Instruction::ZExt:
1491 case Instruction::SExt:
1492 case Instruction::FPToUI:
1493 case Instruction::FPToSI:
1494 case Instruction::FPExt:
1495 case Instruction::PtrToInt:
1496 case Instruction::IntToPtr:
1497 case Instruction::SIToFP:
1498 case Instruction::UIToFP:
1499 case Instruction::Trunc:
1500 case Instruction::FPTrunc:
1501 case Instruction::BitCast: {
1502 Type *SrcTy = VL0->getOperand(0)->getType();
1504 // Calculate the cost of this instruction.
1505 int ScalarCost = VL.size() * TTI->getCastInstrCost(VL0->getOpcode(),
1506 VL0->getType(), SrcTy);
1508 VectorType *SrcVecTy = VectorType::get(SrcTy, VL.size());
1509 int VecCost = TTI->getCastInstrCost(VL0->getOpcode(), VecTy, SrcVecTy);
1510 return VecCost - ScalarCost;
1512 case Instruction::FCmp:
1513 case Instruction::ICmp:
1514 case Instruction::Select:
1515 case Instruction::Add:
1516 case Instruction::FAdd:
1517 case Instruction::Sub:
1518 case Instruction::FSub:
1519 case Instruction::Mul:
1520 case Instruction::FMul:
1521 case Instruction::UDiv:
1522 case Instruction::SDiv:
1523 case Instruction::FDiv:
1524 case Instruction::URem:
1525 case Instruction::SRem:
1526 case Instruction::FRem:
1527 case Instruction::Shl:
1528 case Instruction::LShr:
1529 case Instruction::AShr:
1530 case Instruction::And:
1531 case Instruction::Or:
1532 case Instruction::Xor: {
1533 // Calculate the cost of this instruction.
1536 if (Opcode == Instruction::FCmp || Opcode == Instruction::ICmp ||
1537 Opcode == Instruction::Select) {
1538 VectorType *MaskTy = VectorType::get(Builder.getInt1Ty(), VL.size());
1539 ScalarCost = VecTy->getNumElements() *
1540 TTI->getCmpSelInstrCost(Opcode, ScalarTy, Builder.getInt1Ty());
1541 VecCost = TTI->getCmpSelInstrCost(Opcode, VecTy, MaskTy);
1543 // Certain instructions can be cheaper to vectorize if they have a
1544 // constant second vector operand.
1545 TargetTransformInfo::OperandValueKind Op1VK =
1546 TargetTransformInfo::OK_AnyValue;
1547 TargetTransformInfo::OperandValueKind Op2VK =
1548 TargetTransformInfo::OK_UniformConstantValue;
1549 TargetTransformInfo::OperandValueProperties Op1VP =
1550 TargetTransformInfo::OP_None;
1551 TargetTransformInfo::OperandValueProperties Op2VP =
1552 TargetTransformInfo::OP_None;
1554 // If all operands are exactly the same ConstantInt then set the
1555 // operand kind to OK_UniformConstantValue.
1556 // If instead not all operands are constants, then set the operand kind
1557 // to OK_AnyValue. If all operands are constants but not the same,
1558 // then set the operand kind to OK_NonUniformConstantValue.
1559 ConstantInt *CInt = nullptr;
1560 for (unsigned i = 0; i < VL.size(); ++i) {
1561 const Instruction *I = cast<Instruction>(VL[i]);
1562 if (!isa<ConstantInt>(I->getOperand(1))) {
1563 Op2VK = TargetTransformInfo::OK_AnyValue;
1567 CInt = cast<ConstantInt>(I->getOperand(1));
1570 if (Op2VK == TargetTransformInfo::OK_UniformConstantValue &&
1571 CInt != cast<ConstantInt>(I->getOperand(1)))
1572 Op2VK = TargetTransformInfo::OK_NonUniformConstantValue;
1574 // FIXME: Currently cost of model modification for division by
1575 // power of 2 is handled only for X86. Add support for other targets.
1576 if (Op2VK == TargetTransformInfo::OK_UniformConstantValue && CInt &&
1577 CInt->getValue().isPowerOf2())
1578 Op2VP = TargetTransformInfo::OP_PowerOf2;
1580 ScalarCost = VecTy->getNumElements() *
1581 TTI->getArithmeticInstrCost(Opcode, ScalarTy, Op1VK, Op2VK,
1583 VecCost = TTI->getArithmeticInstrCost(Opcode, VecTy, Op1VK, Op2VK,
1586 return VecCost - ScalarCost;
1588 case Instruction::GetElementPtr: {
1589 TargetTransformInfo::OperandValueKind Op1VK =
1590 TargetTransformInfo::OK_AnyValue;
1591 TargetTransformInfo::OperandValueKind Op2VK =
1592 TargetTransformInfo::OK_UniformConstantValue;
1595 VecTy->getNumElements() *
1596 TTI->getArithmeticInstrCost(Instruction::Add, ScalarTy, Op1VK, Op2VK);
1598 TTI->getArithmeticInstrCost(Instruction::Add, VecTy, Op1VK, Op2VK);
1600 return VecCost - ScalarCost;
1602 case Instruction::Load: {
1603 // Cost of wide load - cost of scalar loads.
1604 int ScalarLdCost = VecTy->getNumElements() *
1605 TTI->getMemoryOpCost(Instruction::Load, ScalarTy, 1, 0);
1606 int VecLdCost = TTI->getMemoryOpCost(Instruction::Load, VecTy, 1, 0);
1607 return VecLdCost - ScalarLdCost;
1609 case Instruction::Store: {
1610 // We know that we can merge the stores. Calculate the cost.
1611 int ScalarStCost = VecTy->getNumElements() *
1612 TTI->getMemoryOpCost(Instruction::Store, ScalarTy, 1, 0);
1613 int VecStCost = TTI->getMemoryOpCost(Instruction::Store, VecTy, 1, 0);
1614 return VecStCost - ScalarStCost;
1616 case Instruction::Call: {
1617 CallInst *CI = cast<CallInst>(VL0);
1618 Intrinsic::ID ID = getIntrinsicIDForCall(CI, TLI);
1620 // Calculate the cost of the scalar and vector calls.
1621 SmallVector<Type*, 4> ScalarTys, VecTys;
1622 for (unsigned op = 0, opc = CI->getNumArgOperands(); op!= opc; ++op) {
1623 ScalarTys.push_back(CI->getArgOperand(op)->getType());
1624 VecTys.push_back(VectorType::get(CI->getArgOperand(op)->getType(),
1625 VecTy->getNumElements()));
1628 int ScalarCallCost = VecTy->getNumElements() *
1629 TTI->getIntrinsicInstrCost(ID, ScalarTy, ScalarTys);
1631 int VecCallCost = TTI->getIntrinsicInstrCost(ID, VecTy, VecTys);
1633 DEBUG(dbgs() << "SLP: Call cost "<< VecCallCost - ScalarCallCost
1634 << " (" << VecCallCost << "-" << ScalarCallCost << ")"
1635 << " for " << *CI << "\n");
1637 return VecCallCost - ScalarCallCost;
1639 case Instruction::ShuffleVector: {
1640 TargetTransformInfo::OperandValueKind Op1VK =
1641 TargetTransformInfo::OK_AnyValue;
1642 TargetTransformInfo::OperandValueKind Op2VK =
1643 TargetTransformInfo::OK_AnyValue;
1646 for (unsigned i = 0; i < VL.size(); ++i) {
1647 Instruction *I = cast<Instruction>(VL[i]);
1651 TTI->getArithmeticInstrCost(I->getOpcode(), ScalarTy, Op1VK, Op2VK);
1653 // VecCost is equal to sum of the cost of creating 2 vectors
1654 // and the cost of creating shuffle.
1655 Instruction *I0 = cast<Instruction>(VL[0]);
1657 TTI->getArithmeticInstrCost(I0->getOpcode(), VecTy, Op1VK, Op2VK);
1658 Instruction *I1 = cast<Instruction>(VL[1]);
1660 TTI->getArithmeticInstrCost(I1->getOpcode(), VecTy, Op1VK, Op2VK);
1662 TTI->getShuffleCost(TargetTransformInfo::SK_Alternate, VecTy, 0);
1663 return VecCost - ScalarCost;
1666 llvm_unreachable("Unknown instruction");
1670 bool BoUpSLP::isFullyVectorizableTinyTree() {
1671 DEBUG(dbgs() << "SLP: Check whether the tree with height " <<
1672 VectorizableTree.size() << " is fully vectorizable .\n");
1674 // We only handle trees of height 2.
1675 if (VectorizableTree.size() != 2)
1678 // Handle splat and all-constants stores.
1679 if (!VectorizableTree[0].NeedToGather &&
1680 (allConstant(VectorizableTree[1].Scalars) ||
1681 isSplat(VectorizableTree[1].Scalars)))
1684 // Gathering cost would be too much for tiny trees.
1685 if (VectorizableTree[0].NeedToGather || VectorizableTree[1].NeedToGather)
1691 int BoUpSLP::getSpillCost() {
1692 // Walk from the bottom of the tree to the top, tracking which values are
1693 // live. When we see a call instruction that is not part of our tree,
1694 // query TTI to see if there is a cost to keeping values live over it
1695 // (for example, if spills and fills are required).
1696 unsigned BundleWidth = VectorizableTree.front().Scalars.size();
1699 SmallPtrSet<Instruction*, 4> LiveValues;
1700 Instruction *PrevInst = nullptr;
1702 for (unsigned N = 0; N < VectorizableTree.size(); ++N) {
1703 Instruction *Inst = dyn_cast<Instruction>(VectorizableTree[N].Scalars[0]);
1713 dbgs() << "SLP: #LV: " << LiveValues.size();
1714 for (auto *X : LiveValues)
1715 dbgs() << " " << X->getName();
1716 dbgs() << ", Looking at ";
1720 // Update LiveValues.
1721 LiveValues.erase(PrevInst);
1722 for (auto &J : PrevInst->operands()) {
1723 if (isa<Instruction>(&*J) && ScalarToTreeEntry.count(&*J))
1724 LiveValues.insert(cast<Instruction>(&*J));
1727 // Now find the sequence of instructions between PrevInst and Inst.
1728 BasicBlock::reverse_iterator InstIt(Inst), PrevInstIt(PrevInst);
1730 while (InstIt != PrevInstIt) {
1731 if (PrevInstIt == PrevInst->getParent()->rend()) {
1732 PrevInstIt = Inst->getParent()->rbegin();
1736 if (isa<CallInst>(&*PrevInstIt) && &*PrevInstIt != PrevInst) {
1737 SmallVector<Type*, 4> V;
1738 for (auto *II : LiveValues)
1739 V.push_back(VectorType::get(II->getType(), BundleWidth));
1740 Cost += TTI->getCostOfKeepingLiveOverCall(V);
1749 DEBUG(dbgs() << "SLP: SpillCost=" << Cost << "\n");
1753 int BoUpSLP::getTreeCost() {
1755 DEBUG(dbgs() << "SLP: Calculating cost for tree of size " <<
1756 VectorizableTree.size() << ".\n");
1758 // We only vectorize tiny trees if it is fully vectorizable.
1759 if (VectorizableTree.size() < 3 && !isFullyVectorizableTinyTree()) {
1760 if (VectorizableTree.empty()) {
1761 assert(!ExternalUses.size() && "We should not have any external users");
1766 unsigned BundleWidth = VectorizableTree[0].Scalars.size();
1768 for (unsigned i = 0, e = VectorizableTree.size(); i != e; ++i) {
1769 int C = getEntryCost(&VectorizableTree[i]);
1770 DEBUG(dbgs() << "SLP: Adding cost " << C << " for bundle that starts with "
1771 << *VectorizableTree[i].Scalars[0] << " .\n");
1775 SmallSet<Value *, 16> ExtractCostCalculated;
1776 int ExtractCost = 0;
1777 for (UserList::iterator I = ExternalUses.begin(), E = ExternalUses.end();
1779 // We only add extract cost once for the same scalar.
1780 if (!ExtractCostCalculated.insert(I->Scalar).second)
1783 // Uses by ephemeral values are free (because the ephemeral value will be
1784 // removed prior to code generation, and so the extraction will be
1785 // removed as well).
1786 if (EphValues.count(I->User))
1789 VectorType *VecTy = VectorType::get(I->Scalar->getType(), BundleWidth);
1790 ExtractCost += TTI->getVectorInstrCost(Instruction::ExtractElement, VecTy,
1794 Cost += getSpillCost();
1796 DEBUG(dbgs() << "SLP: Total Cost " << Cost + ExtractCost<< ".\n");
1797 return Cost + ExtractCost;
1800 int BoUpSLP::getGatherCost(Type *Ty) {
1802 for (unsigned i = 0, e = cast<VectorType>(Ty)->getNumElements(); i < e; ++i)
1803 Cost += TTI->getVectorInstrCost(Instruction::InsertElement, Ty, i);
1807 int BoUpSLP::getGatherCost(ArrayRef<Value *> VL) {
1808 // Find the type of the operands in VL.
1809 Type *ScalarTy = VL[0]->getType();
1810 if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
1811 ScalarTy = SI->getValueOperand()->getType();
1812 VectorType *VecTy = VectorType::get(ScalarTy, VL.size());
1813 // Find the cost of inserting/extracting values from the vector.
1814 return getGatherCost(VecTy);
1817 Value *BoUpSLP::getPointerOperand(Value *I) {
1818 if (LoadInst *LI = dyn_cast<LoadInst>(I))
1819 return LI->getPointerOperand();
1820 if (StoreInst *SI = dyn_cast<StoreInst>(I))
1821 return SI->getPointerOperand();
1825 unsigned BoUpSLP::getAddressSpaceOperand(Value *I) {
1826 if (LoadInst *L = dyn_cast<LoadInst>(I))
1827 return L->getPointerAddressSpace();
1828 if (StoreInst *S = dyn_cast<StoreInst>(I))
1829 return S->getPointerAddressSpace();
1833 bool BoUpSLP::isConsecutiveAccess(Value *A, Value *B, const DataLayout &DL) {
1834 Value *PtrA = getPointerOperand(A);
1835 Value *PtrB = getPointerOperand(B);
1836 unsigned ASA = getAddressSpaceOperand(A);
1837 unsigned ASB = getAddressSpaceOperand(B);
1839 // Check that the address spaces match and that the pointers are valid.
1840 if (!PtrA || !PtrB || (ASA != ASB))
1843 // Make sure that A and B are different pointers of the same type.
1844 if (PtrA == PtrB || PtrA->getType() != PtrB->getType())
1847 unsigned PtrBitWidth = DL.getPointerSizeInBits(ASA);
1848 Type *Ty = cast<PointerType>(PtrA->getType())->getElementType();
1849 APInt Size(PtrBitWidth, DL.getTypeStoreSize(Ty));
1851 APInt OffsetA(PtrBitWidth, 0), OffsetB(PtrBitWidth, 0);
1852 PtrA = PtrA->stripAndAccumulateInBoundsConstantOffsets(DL, OffsetA);
1853 PtrB = PtrB->stripAndAccumulateInBoundsConstantOffsets(DL, OffsetB);
1855 APInt OffsetDelta = OffsetB - OffsetA;
1857 // Check if they are based on the same pointer. That makes the offsets
1860 return OffsetDelta == Size;
1862 // Compute the necessary base pointer delta to have the necessary final delta
1863 // equal to the size.
1864 APInt BaseDelta = Size - OffsetDelta;
1866 // Otherwise compute the distance with SCEV between the base pointers.
1867 const SCEV *PtrSCEVA = SE->getSCEV(PtrA);
1868 const SCEV *PtrSCEVB = SE->getSCEV(PtrB);
1869 const SCEV *C = SE->getConstant(BaseDelta);
1870 const SCEV *X = SE->getAddExpr(PtrSCEVA, C);
1871 return X == PtrSCEVB;
1874 // Reorder commutative operations in alternate shuffle if the resulting vectors
1875 // are consecutive loads. This would allow us to vectorize the tree.
1876 // If we have something like-
1877 // load a[0] - load b[0]
1878 // load b[1] + load a[1]
1879 // load a[2] - load b[2]
1880 // load a[3] + load b[3]
1881 // Reordering the second load b[1] load a[1] would allow us to vectorize this
1883 void BoUpSLP::reorderAltShuffleOperands(ArrayRef<Value *> VL,
1884 SmallVectorImpl<Value *> &Left,
1885 SmallVectorImpl<Value *> &Right) {
1886 const DataLayout &DL = F->getParent()->getDataLayout();
1888 // Push left and right operands of binary operation into Left and Right
1889 for (unsigned i = 0, e = VL.size(); i < e; ++i) {
1890 Left.push_back(cast<Instruction>(VL[i])->getOperand(0));
1891 Right.push_back(cast<Instruction>(VL[i])->getOperand(1));
1894 // Reorder if we have a commutative operation and consecutive access
1895 // are on either side of the alternate instructions.
1896 for (unsigned j = 0; j < VL.size() - 1; ++j) {
1897 if (LoadInst *L = dyn_cast<LoadInst>(Left[j])) {
1898 if (LoadInst *L1 = dyn_cast<LoadInst>(Right[j + 1])) {
1899 Instruction *VL1 = cast<Instruction>(VL[j]);
1900 Instruction *VL2 = cast<Instruction>(VL[j + 1]);
1901 if (isConsecutiveAccess(L, L1, DL) && VL1->isCommutative()) {
1902 std::swap(Left[j], Right[j]);
1904 } else if (isConsecutiveAccess(L, L1, DL) && VL2->isCommutative()) {
1905 std::swap(Left[j + 1], Right[j + 1]);
1911 if (LoadInst *L = dyn_cast<LoadInst>(Right[j])) {
1912 if (LoadInst *L1 = dyn_cast<LoadInst>(Left[j + 1])) {
1913 Instruction *VL1 = cast<Instruction>(VL[j]);
1914 Instruction *VL2 = cast<Instruction>(VL[j + 1]);
1915 if (isConsecutiveAccess(L, L1, DL) && VL1->isCommutative()) {
1916 std::swap(Left[j], Right[j]);
1918 } else if (isConsecutiveAccess(L, L1, DL) && VL2->isCommutative()) {
1919 std::swap(Left[j + 1], Right[j + 1]);
1928 void BoUpSLP::reorderInputsAccordingToOpcode(ArrayRef<Value *> VL,
1929 SmallVectorImpl<Value *> &Left,
1930 SmallVectorImpl<Value *> &Right) {
1932 SmallVector<Value *, 16> OrigLeft, OrigRight;
1934 bool AllSameOpcodeLeft = true;
1935 bool AllSameOpcodeRight = true;
1936 for (unsigned i = 0, e = VL.size(); i != e; ++i) {
1937 Instruction *I = cast<Instruction>(VL[i]);
1938 Value *VLeft = I->getOperand(0);
1939 Value *VRight = I->getOperand(1);
1941 OrigLeft.push_back(VLeft);
1942 OrigRight.push_back(VRight);
1944 Instruction *ILeft = dyn_cast<Instruction>(VLeft);
1945 Instruction *IRight = dyn_cast<Instruction>(VRight);
1947 // Check whether all operands on one side have the same opcode. In this case
1948 // we want to preserve the original order and not make things worse by
1950 if (i && AllSameOpcodeLeft && ILeft) {
1951 if (Instruction *PLeft = dyn_cast<Instruction>(OrigLeft[i - 1])) {
1952 if (PLeft->getOpcode() != ILeft->getOpcode())
1953 AllSameOpcodeLeft = false;
1955 AllSameOpcodeLeft = false;
1957 if (i && AllSameOpcodeRight && IRight) {
1958 if (Instruction *PRight = dyn_cast<Instruction>(OrigRight[i - 1])) {
1959 if (PRight->getOpcode() != IRight->getOpcode())
1960 AllSameOpcodeRight = false;
1962 AllSameOpcodeRight = false;
1965 // Sort two opcodes. In the code below we try to preserve the ability to use
1966 // broadcast of values instead of individual inserts.
1973 // If we just sorted according to opcode we would leave the first line in
1974 // tact but we would swap vl2 with vr2 because opcode(phi) > opcode(load).
1977 // Because vr2 and vr1 are from the same load we loose the opportunity of a
1978 // broadcast for the packed right side in the backend: we have [vr1, vl2]
1979 // instead of [vr1, vr2=vr1].
1980 if (ILeft && IRight) {
1981 if (!i && ILeft->getOpcode() > IRight->getOpcode()) {
1982 Left.push_back(IRight);
1983 Right.push_back(ILeft);
1984 } else if (i && ILeft->getOpcode() > IRight->getOpcode() &&
1985 Right[i - 1] != IRight) {
1986 // Try not to destroy a broad cast for no apparent benefit.
1987 Left.push_back(IRight);
1988 Right.push_back(ILeft);
1989 } else if (i && ILeft->getOpcode() == IRight->getOpcode() &&
1990 Right[i - 1] == ILeft) {
1991 // Try preserve broadcasts.
1992 Left.push_back(IRight);
1993 Right.push_back(ILeft);
1994 } else if (i && ILeft->getOpcode() == IRight->getOpcode() &&
1995 Left[i - 1] == IRight) {
1996 // Try preserve broadcasts.
1997 Left.push_back(IRight);
1998 Right.push_back(ILeft);
2000 Left.push_back(ILeft);
2001 Right.push_back(IRight);
2005 // One opcode, put the instruction on the right.
2007 Left.push_back(VRight);
2008 Right.push_back(ILeft);
2011 Left.push_back(VLeft);
2012 Right.push_back(VRight);
2015 bool LeftBroadcast = isSplat(Left);
2016 bool RightBroadcast = isSplat(Right);
2018 // If operands end up being broadcast return this operand order.
2019 if (LeftBroadcast || RightBroadcast)
2022 // Don't reorder if the operands where good to begin.
2023 if (AllSameOpcodeRight || AllSameOpcodeLeft) {
2028 const DataLayout &DL = F->getParent()->getDataLayout();
2030 // Finally check if we can get longer vectorizable chain by reordering
2031 // without breaking the good operand order detected above.
2032 // E.g. If we have something like-
2033 // load a[0] load b[0]
2034 // load b[1] load a[1]
2035 // load a[2] load b[2]
2036 // load a[3] load b[3]
2037 // Reordering the second load b[1] load a[1] would allow us to vectorize
2038 // this code and we still retain AllSameOpcode property.
2039 // FIXME: This load reordering might break AllSameOpcode in some rare cases
2041 // add a[0],c[0] load b[0]
2042 // add a[1],c[2] load b[1]
2044 // add a[3],c[3] load b[3]
2045 for (unsigned j = 0; j < VL.size() - 1; ++j) {
2046 if (LoadInst *L = dyn_cast<LoadInst>(Left[j])) {
2047 if (LoadInst *L1 = dyn_cast<LoadInst>(Right[j + 1])) {
2048 if (isConsecutiveAccess(L, L1, DL)) {
2049 std::swap(Left[j + 1], Right[j + 1]);
2054 if (LoadInst *L = dyn_cast<LoadInst>(Right[j])) {
2055 if (LoadInst *L1 = dyn_cast<LoadInst>(Left[j + 1])) {
2056 if (isConsecutiveAccess(L, L1, DL)) {
2057 std::swap(Left[j + 1], Right[j + 1]);
2066 void BoUpSLP::setInsertPointAfterBundle(ArrayRef<Value *> VL) {
2067 Instruction *VL0 = cast<Instruction>(VL[0]);
2068 BasicBlock::iterator NextInst = VL0;
2070 Builder.SetInsertPoint(VL0->getParent(), NextInst);
2071 Builder.SetCurrentDebugLocation(VL0->getDebugLoc());
2074 Value *BoUpSLP::Gather(ArrayRef<Value *> VL, VectorType *Ty) {
2075 Value *Vec = UndefValue::get(Ty);
2076 // Generate the 'InsertElement' instruction.
2077 for (unsigned i = 0; i < Ty->getNumElements(); ++i) {
2078 Vec = Builder.CreateInsertElement(Vec, VL[i], Builder.getInt32(i));
2079 if (Instruction *Insrt = dyn_cast<Instruction>(Vec)) {
2080 GatherSeq.insert(Insrt);
2081 CSEBlocks.insert(Insrt->getParent());
2083 // Add to our 'need-to-extract' list.
2084 if (ScalarToTreeEntry.count(VL[i])) {
2085 int Idx = ScalarToTreeEntry[VL[i]];
2086 TreeEntry *E = &VectorizableTree[Idx];
2087 // Find which lane we need to extract.
2089 for (unsigned Lane = 0, LE = VL.size(); Lane != LE; ++Lane) {
2090 // Is this the lane of the scalar that we are looking for ?
2091 if (E->Scalars[Lane] == VL[i]) {
2096 assert(FoundLane >= 0 && "Could not find the correct lane");
2097 ExternalUses.push_back(ExternalUser(VL[i], Insrt, FoundLane));
2105 Value *BoUpSLP::alreadyVectorized(ArrayRef<Value *> VL) const {
2106 SmallDenseMap<Value*, int>::const_iterator Entry
2107 = ScalarToTreeEntry.find(VL[0]);
2108 if (Entry != ScalarToTreeEntry.end()) {
2109 int Idx = Entry->second;
2110 const TreeEntry *En = &VectorizableTree[Idx];
2111 if (En->isSame(VL) && En->VectorizedValue)
2112 return En->VectorizedValue;
2117 Value *BoUpSLP::vectorizeTree(ArrayRef<Value *> VL) {
2118 if (ScalarToTreeEntry.count(VL[0])) {
2119 int Idx = ScalarToTreeEntry[VL[0]];
2120 TreeEntry *E = &VectorizableTree[Idx];
2122 return vectorizeTree(E);
2125 Type *ScalarTy = VL[0]->getType();
2126 if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
2127 ScalarTy = SI->getValueOperand()->getType();
2128 VectorType *VecTy = VectorType::get(ScalarTy, VL.size());
2130 return Gather(VL, VecTy);
2133 Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
2134 IRBuilder<>::InsertPointGuard Guard(Builder);
2136 if (E->VectorizedValue) {
2137 DEBUG(dbgs() << "SLP: Diamond merged for " << *E->Scalars[0] << ".\n");
2138 return E->VectorizedValue;
2141 Instruction *VL0 = cast<Instruction>(E->Scalars[0]);
2142 Type *ScalarTy = VL0->getType();
2143 if (StoreInst *SI = dyn_cast<StoreInst>(VL0))
2144 ScalarTy = SI->getValueOperand()->getType();
2145 VectorType *VecTy = VectorType::get(ScalarTy, E->Scalars.size());
2147 if (E->NeedToGather) {
2148 setInsertPointAfterBundle(E->Scalars);
2149 return Gather(E->Scalars, VecTy);
2152 const DataLayout &DL = F->getParent()->getDataLayout();
2153 unsigned Opcode = getSameOpcode(E->Scalars);
2156 case Instruction::PHI: {
2157 PHINode *PH = dyn_cast<PHINode>(VL0);
2158 Builder.SetInsertPoint(PH->getParent()->getFirstNonPHI());
2159 Builder.SetCurrentDebugLocation(PH->getDebugLoc());
2160 PHINode *NewPhi = Builder.CreatePHI(VecTy, PH->getNumIncomingValues());
2161 E->VectorizedValue = NewPhi;
2163 // PHINodes may have multiple entries from the same block. We want to
2164 // visit every block once.
2165 SmallSet<BasicBlock*, 4> VisitedBBs;
2167 for (unsigned i = 0, e = PH->getNumIncomingValues(); i < e; ++i) {
2169 BasicBlock *IBB = PH->getIncomingBlock(i);
2171 if (!VisitedBBs.insert(IBB).second) {
2172 NewPhi->addIncoming(NewPhi->getIncomingValueForBlock(IBB), IBB);
2176 // Prepare the operand vector.
2177 for (Value *V : E->Scalars)
2178 Operands.push_back(cast<PHINode>(V)->getIncomingValueForBlock(IBB));
2180 Builder.SetInsertPoint(IBB->getTerminator());
2181 Builder.SetCurrentDebugLocation(PH->getDebugLoc());
2182 Value *Vec = vectorizeTree(Operands);
2183 NewPhi->addIncoming(Vec, IBB);
2186 assert(NewPhi->getNumIncomingValues() == PH->getNumIncomingValues() &&
2187 "Invalid number of incoming values");
2191 case Instruction::ExtractElement: {
2192 if (CanReuseExtract(E->Scalars)) {
2193 Value *V = VL0->getOperand(0);
2194 E->VectorizedValue = V;
2197 return Gather(E->Scalars, VecTy);
2199 case Instruction::ZExt:
2200 case Instruction::SExt:
2201 case Instruction::FPToUI:
2202 case Instruction::FPToSI:
2203 case Instruction::FPExt:
2204 case Instruction::PtrToInt:
2205 case Instruction::IntToPtr:
2206 case Instruction::SIToFP:
2207 case Instruction::UIToFP:
2208 case Instruction::Trunc:
2209 case Instruction::FPTrunc:
2210 case Instruction::BitCast: {
2212 for (Value *V : E->Scalars)
2213 INVL.push_back(cast<Instruction>(V)->getOperand(0));
2215 setInsertPointAfterBundle(E->Scalars);
2217 Value *InVec = vectorizeTree(INVL);
2219 if (Value *V = alreadyVectorized(E->Scalars))
2222 CastInst *CI = dyn_cast<CastInst>(VL0);
2223 Value *V = Builder.CreateCast(CI->getOpcode(), InVec, VecTy);
2224 E->VectorizedValue = V;
2225 ++NumVectorInstructions;
2228 case Instruction::FCmp:
2229 case Instruction::ICmp: {
2230 ValueList LHSV, RHSV;
2231 for (Value *V : E->Scalars) {
2232 LHSV.push_back(cast<Instruction>(V)->getOperand(0));
2233 RHSV.push_back(cast<Instruction>(V)->getOperand(1));
2236 setInsertPointAfterBundle(E->Scalars);
2238 Value *L = vectorizeTree(LHSV);
2239 Value *R = vectorizeTree(RHSV);
2241 if (Value *V = alreadyVectorized(E->Scalars))
2244 CmpInst::Predicate P0 = cast<CmpInst>(VL0)->getPredicate();
2246 if (Opcode == Instruction::FCmp)
2247 V = Builder.CreateFCmp(P0, L, R);
2249 V = Builder.CreateICmp(P0, L, R);
2251 E->VectorizedValue = V;
2252 ++NumVectorInstructions;
2255 case Instruction::Select: {
2256 ValueList TrueVec, FalseVec, CondVec;
2257 for (Value *V : E->Scalars) {
2258 CondVec.push_back(cast<Instruction>(V)->getOperand(0));
2259 TrueVec.push_back(cast<Instruction>(V)->getOperand(1));
2260 FalseVec.push_back(cast<Instruction>(V)->getOperand(2));
2263 setInsertPointAfterBundle(E->Scalars);
2265 Value *Cond = vectorizeTree(CondVec);
2266 Value *True = vectorizeTree(TrueVec);
2267 Value *False = vectorizeTree(FalseVec);
2269 if (Value *V = alreadyVectorized(E->Scalars))
2272 Value *V = Builder.CreateSelect(Cond, True, False);
2273 E->VectorizedValue = V;
2274 ++NumVectorInstructions;
2277 case Instruction::Add:
2278 case Instruction::FAdd:
2279 case Instruction::Sub:
2280 case Instruction::FSub:
2281 case Instruction::Mul:
2282 case Instruction::FMul:
2283 case Instruction::UDiv:
2284 case Instruction::SDiv:
2285 case Instruction::FDiv:
2286 case Instruction::URem:
2287 case Instruction::SRem:
2288 case Instruction::FRem:
2289 case Instruction::Shl:
2290 case Instruction::LShr:
2291 case Instruction::AShr:
2292 case Instruction::And:
2293 case Instruction::Or:
2294 case Instruction::Xor: {
2295 ValueList LHSVL, RHSVL;
2296 if (isa<BinaryOperator>(VL0) && VL0->isCommutative())
2297 reorderInputsAccordingToOpcode(E->Scalars, LHSVL, RHSVL);
2299 for (Value *V : E->Scalars) {
2300 LHSVL.push_back(cast<Instruction>(V)->getOperand(0));
2301 RHSVL.push_back(cast<Instruction>(V)->getOperand(1));
2304 setInsertPointAfterBundle(E->Scalars);
2306 Value *LHS = vectorizeTree(LHSVL);
2307 Value *RHS = vectorizeTree(RHSVL);
2309 if (LHS == RHS && isa<Instruction>(LHS)) {
2310 assert((VL0->getOperand(0) == VL0->getOperand(1)) && "Invalid order");
2313 if (Value *V = alreadyVectorized(E->Scalars))
2316 BinaryOperator *BinOp = cast<BinaryOperator>(VL0);
2317 Value *V = Builder.CreateBinOp(BinOp->getOpcode(), LHS, RHS);
2318 E->VectorizedValue = V;
2319 propagateIRFlags(E->VectorizedValue, E->Scalars);
2320 ++NumVectorInstructions;
2322 if (Instruction *I = dyn_cast<Instruction>(V))
2323 return propagateMetadata(I, E->Scalars);
2327 case Instruction::Load: {
2328 // Loads are inserted at the head of the tree because we don't want to
2329 // sink them all the way down past store instructions.
2330 setInsertPointAfterBundle(E->Scalars);
2332 LoadInst *LI = cast<LoadInst>(VL0);
2333 Type *ScalarLoadTy = LI->getType();
2334 unsigned AS = LI->getPointerAddressSpace();
2336 Value *VecPtr = Builder.CreateBitCast(LI->getPointerOperand(),
2337 VecTy->getPointerTo(AS));
2339 // The pointer operand uses an in-tree scalar so we add the new BitCast to
2340 // ExternalUses list to make sure that an extract will be generated in the
2342 if (ScalarToTreeEntry.count(LI->getPointerOperand()))
2343 ExternalUses.push_back(
2344 ExternalUser(LI->getPointerOperand(), cast<User>(VecPtr), 0));
2346 unsigned Alignment = LI->getAlignment();
2347 LI = Builder.CreateLoad(VecPtr);
2349 Alignment = DL.getABITypeAlignment(ScalarLoadTy);
2351 LI->setAlignment(Alignment);
2352 E->VectorizedValue = LI;
2353 ++NumVectorInstructions;
2354 return propagateMetadata(LI, E->Scalars);
2356 case Instruction::Store: {
2357 StoreInst *SI = cast<StoreInst>(VL0);
2358 unsigned Alignment = SI->getAlignment();
2359 unsigned AS = SI->getPointerAddressSpace();
2362 for (Value *V : E->Scalars)
2363 ValueOp.push_back(cast<StoreInst>(V)->getValueOperand());
2365 setInsertPointAfterBundle(E->Scalars);
2367 Value *VecValue = vectorizeTree(ValueOp);
2368 Value *VecPtr = Builder.CreateBitCast(SI->getPointerOperand(),
2369 VecTy->getPointerTo(AS));
2370 StoreInst *S = Builder.CreateStore(VecValue, VecPtr);
2372 // The pointer operand uses an in-tree scalar so we add the new BitCast to
2373 // ExternalUses list to make sure that an extract will be generated in the
2375 if (ScalarToTreeEntry.count(SI->getPointerOperand()))
2376 ExternalUses.push_back(
2377 ExternalUser(SI->getPointerOperand(), cast<User>(VecPtr), 0));
2380 Alignment = DL.getABITypeAlignment(SI->getValueOperand()->getType());
2382 S->setAlignment(Alignment);
2383 E->VectorizedValue = S;
2384 ++NumVectorInstructions;
2385 return propagateMetadata(S, E->Scalars);
2387 case Instruction::GetElementPtr: {
2388 setInsertPointAfterBundle(E->Scalars);
2391 for (Value *V : E->Scalars)
2392 Op0VL.push_back(cast<GetElementPtrInst>(V)->getOperand(0));
2394 Value *Op0 = vectorizeTree(Op0VL);
2396 std::vector<Value *> OpVecs;
2397 for (int j = 1, e = cast<GetElementPtrInst>(VL0)->getNumOperands(); j < e;
2400 for (Value *V : E->Scalars)
2401 OpVL.push_back(cast<GetElementPtrInst>(V)->getOperand(j));
2403 Value *OpVec = vectorizeTree(OpVL);
2404 OpVecs.push_back(OpVec);
2407 Value *V = Builder.CreateGEP(
2408 cast<GetElementPtrInst>(VL0)->getSourceElementType(), Op0, OpVecs);
2409 E->VectorizedValue = V;
2410 ++NumVectorInstructions;
2412 if (Instruction *I = dyn_cast<Instruction>(V))
2413 return propagateMetadata(I, E->Scalars);
2417 case Instruction::Call: {
2418 CallInst *CI = cast<CallInst>(VL0);
2419 setInsertPointAfterBundle(E->Scalars);
2421 Intrinsic::ID IID = Intrinsic::not_intrinsic;
2422 Value *ScalarArg = nullptr;
2423 if (CI && (FI = CI->getCalledFunction())) {
2424 IID = FI->getIntrinsicID();
2426 std::vector<Value *> OpVecs;
2427 for (int j = 0, e = CI->getNumArgOperands(); j < e; ++j) {
2429 // ctlz,cttz and powi are special intrinsics whose second argument is
2430 // a scalar. This argument should not be vectorized.
2431 if (hasVectorInstrinsicScalarOpd(IID, 1) && j == 1) {
2432 CallInst *CEI = cast<CallInst>(E->Scalars[0]);
2433 ScalarArg = CEI->getArgOperand(j);
2434 OpVecs.push_back(CEI->getArgOperand(j));
2437 for (Value *V : E->Scalars) {
2438 CallInst *CEI = cast<CallInst>(V);
2439 OpVL.push_back(CEI->getArgOperand(j));
2442 Value *OpVec = vectorizeTree(OpVL);
2443 DEBUG(dbgs() << "SLP: OpVec[" << j << "]: " << *OpVec << "\n");
2444 OpVecs.push_back(OpVec);
2447 Module *M = F->getParent();
2448 Intrinsic::ID ID = getIntrinsicIDForCall(CI, TLI);
2449 Type *Tys[] = { VectorType::get(CI->getType(), E->Scalars.size()) };
2450 Function *CF = Intrinsic::getDeclaration(M, ID, Tys);
2451 Value *V = Builder.CreateCall(CF, OpVecs);
2453 // The scalar argument uses an in-tree scalar so we add the new vectorized
2454 // call to ExternalUses list to make sure that an extract will be
2455 // generated in the future.
2456 if (ScalarArg && ScalarToTreeEntry.count(ScalarArg))
2457 ExternalUses.push_back(ExternalUser(ScalarArg, cast<User>(V), 0));
2459 E->VectorizedValue = V;
2460 ++NumVectorInstructions;
2463 case Instruction::ShuffleVector: {
2464 ValueList LHSVL, RHSVL;
2465 assert(isa<BinaryOperator>(VL0) && "Invalid Shuffle Vector Operand");
2466 reorderAltShuffleOperands(E->Scalars, LHSVL, RHSVL);
2467 setInsertPointAfterBundle(E->Scalars);
2469 Value *LHS = vectorizeTree(LHSVL);
2470 Value *RHS = vectorizeTree(RHSVL);
2472 if (Value *V = alreadyVectorized(E->Scalars))
2475 // Create a vector of LHS op1 RHS
2476 BinaryOperator *BinOp0 = cast<BinaryOperator>(VL0);
2477 Value *V0 = Builder.CreateBinOp(BinOp0->getOpcode(), LHS, RHS);
2479 // Create a vector of LHS op2 RHS
2480 Instruction *VL1 = cast<Instruction>(E->Scalars[1]);
2481 BinaryOperator *BinOp1 = cast<BinaryOperator>(VL1);
2482 Value *V1 = Builder.CreateBinOp(BinOp1->getOpcode(), LHS, RHS);
2484 // Create shuffle to take alternate operations from the vector.
2485 // Also, gather up odd and even scalar ops to propagate IR flags to
2486 // each vector operation.
2487 ValueList OddScalars, EvenScalars;
2488 unsigned e = E->Scalars.size();
2489 SmallVector<Constant *, 8> Mask(e);
2490 for (unsigned i = 0; i < e; ++i) {
2492 Mask[i] = Builder.getInt32(e + i);
2493 OddScalars.push_back(E->Scalars[i]);
2495 Mask[i] = Builder.getInt32(i);
2496 EvenScalars.push_back(E->Scalars[i]);
2500 Value *ShuffleMask = ConstantVector::get(Mask);
2501 propagateIRFlags(V0, EvenScalars);
2502 propagateIRFlags(V1, OddScalars);
2504 Value *V = Builder.CreateShuffleVector(V0, V1, ShuffleMask);
2505 E->VectorizedValue = V;
2506 ++NumVectorInstructions;
2507 if (Instruction *I = dyn_cast<Instruction>(V))
2508 return propagateMetadata(I, E->Scalars);
2513 llvm_unreachable("unknown inst");
2518 Value *BoUpSLP::vectorizeTree() {
2520 // All blocks must be scheduled before any instructions are inserted.
2521 for (auto &BSIter : BlocksSchedules) {
2522 scheduleBlock(BSIter.second.get());
2525 Builder.SetInsertPoint(F->getEntryBlock().begin());
2526 vectorizeTree(&VectorizableTree[0]);
2528 DEBUG(dbgs() << "SLP: Extracting " << ExternalUses.size() << " values .\n");
2530 // Extract all of the elements with the external uses.
2531 for (UserList::iterator it = ExternalUses.begin(), e = ExternalUses.end();
2533 Value *Scalar = it->Scalar;
2534 llvm::User *User = it->User;
2536 // Skip users that we already RAUW. This happens when one instruction
2537 // has multiple uses of the same value.
2538 if (std::find(Scalar->user_begin(), Scalar->user_end(), User) ==
2541 assert(ScalarToTreeEntry.count(Scalar) && "Invalid scalar");
2543 int Idx = ScalarToTreeEntry[Scalar];
2544 TreeEntry *E = &VectorizableTree[Idx];
2545 assert(!E->NeedToGather && "Extracting from a gather list");
2547 Value *Vec = E->VectorizedValue;
2548 assert(Vec && "Can't find vectorizable value");
2550 Value *Lane = Builder.getInt32(it->Lane);
2551 // Generate extracts for out-of-tree users.
2552 // Find the insertion point for the extractelement lane.
2553 if (isa<Instruction>(Vec)){
2554 if (PHINode *PH = dyn_cast<PHINode>(User)) {
2555 for (int i = 0, e = PH->getNumIncomingValues(); i != e; ++i) {
2556 if (PH->getIncomingValue(i) == Scalar) {
2557 Builder.SetInsertPoint(PH->getIncomingBlock(i)->getTerminator());
2558 Value *Ex = Builder.CreateExtractElement(Vec, Lane);
2559 CSEBlocks.insert(PH->getIncomingBlock(i));
2560 PH->setOperand(i, Ex);
2564 Builder.SetInsertPoint(cast<Instruction>(User));
2565 Value *Ex = Builder.CreateExtractElement(Vec, Lane);
2566 CSEBlocks.insert(cast<Instruction>(User)->getParent());
2567 User->replaceUsesOfWith(Scalar, Ex);
2570 Builder.SetInsertPoint(F->getEntryBlock().begin());
2571 Value *Ex = Builder.CreateExtractElement(Vec, Lane);
2572 CSEBlocks.insert(&F->getEntryBlock());
2573 User->replaceUsesOfWith(Scalar, Ex);
2576 DEBUG(dbgs() << "SLP: Replaced:" << *User << ".\n");
2579 // For each vectorized value:
2580 for (int EIdx = 0, EE = VectorizableTree.size(); EIdx < EE; ++EIdx) {
2581 TreeEntry *Entry = &VectorizableTree[EIdx];
2584 for (int Lane = 0, LE = Entry->Scalars.size(); Lane != LE; ++Lane) {
2585 Value *Scalar = Entry->Scalars[Lane];
2586 // No need to handle users of gathered values.
2587 if (Entry->NeedToGather)
2590 assert(Entry->VectorizedValue && "Can't find vectorizable value");
2592 Type *Ty = Scalar->getType();
2593 if (!Ty->isVoidTy()) {
2595 for (User *U : Scalar->users()) {
2596 DEBUG(dbgs() << "SLP: \tvalidating user:" << *U << ".\n");
2598 assert((ScalarToTreeEntry.count(U) ||
2599 // It is legal to replace users in the ignorelist by undef.
2600 (std::find(UserIgnoreList.begin(), UserIgnoreList.end(), U) !=
2601 UserIgnoreList.end())) &&
2602 "Replacing out-of-tree value with undef");
2605 Value *Undef = UndefValue::get(Ty);
2606 Scalar->replaceAllUsesWith(Undef);
2608 DEBUG(dbgs() << "SLP: \tErasing scalar:" << *Scalar << ".\n");
2609 eraseInstruction(cast<Instruction>(Scalar));
2613 Builder.ClearInsertionPoint();
2615 return VectorizableTree[0].VectorizedValue;
2618 void BoUpSLP::optimizeGatherSequence() {
2619 DEBUG(dbgs() << "SLP: Optimizing " << GatherSeq.size()
2620 << " gather sequences instructions.\n");
2621 // LICM InsertElementInst sequences.
2622 for (SetVector<Instruction *>::iterator it = GatherSeq.begin(),
2623 e = GatherSeq.end(); it != e; ++it) {
2624 InsertElementInst *Insert = dyn_cast<InsertElementInst>(*it);
2629 // Check if this block is inside a loop.
2630 Loop *L = LI->getLoopFor(Insert->getParent());
2634 // Check if it has a preheader.
2635 BasicBlock *PreHeader = L->getLoopPreheader();
2639 // If the vector or the element that we insert into it are
2640 // instructions that are defined in this basic block then we can't
2641 // hoist this instruction.
2642 Instruction *CurrVec = dyn_cast<Instruction>(Insert->getOperand(0));
2643 Instruction *NewElem = dyn_cast<Instruction>(Insert->getOperand(1));
2644 if (CurrVec && L->contains(CurrVec))
2646 if (NewElem && L->contains(NewElem))
2649 // We can hoist this instruction. Move it to the pre-header.
2650 Insert->moveBefore(PreHeader->getTerminator());
2653 // Make a list of all reachable blocks in our CSE queue.
2654 SmallVector<const DomTreeNode *, 8> CSEWorkList;
2655 CSEWorkList.reserve(CSEBlocks.size());
2656 for (BasicBlock *BB : CSEBlocks)
2657 if (DomTreeNode *N = DT->getNode(BB)) {
2658 assert(DT->isReachableFromEntry(N));
2659 CSEWorkList.push_back(N);
2662 // Sort blocks by domination. This ensures we visit a block after all blocks
2663 // dominating it are visited.
2664 std::stable_sort(CSEWorkList.begin(), CSEWorkList.end(),
2665 [this](const DomTreeNode *A, const DomTreeNode *B) {
2666 return DT->properlyDominates(A, B);
2669 // Perform O(N^2) search over the gather sequences and merge identical
2670 // instructions. TODO: We can further optimize this scan if we split the
2671 // instructions into different buckets based on the insert lane.
2672 SmallVector<Instruction *, 16> Visited;
2673 for (auto I = CSEWorkList.begin(), E = CSEWorkList.end(); I != E; ++I) {
2674 assert((I == CSEWorkList.begin() || !DT->dominates(*I, *std::prev(I))) &&
2675 "Worklist not sorted properly!");
2676 BasicBlock *BB = (*I)->getBlock();
2677 // For all instructions in blocks containing gather sequences:
2678 for (BasicBlock::iterator it = BB->begin(), e = BB->end(); it != e;) {
2679 Instruction *In = it++;
2680 if (!isa<InsertElementInst>(In) && !isa<ExtractElementInst>(In))
2683 // Check if we can replace this instruction with any of the
2684 // visited instructions.
2685 for (SmallVectorImpl<Instruction *>::iterator v = Visited.begin(),
2688 if (In->isIdenticalTo(*v) &&
2689 DT->dominates((*v)->getParent(), In->getParent())) {
2690 In->replaceAllUsesWith(*v);
2691 eraseInstruction(In);
2697 assert(std::find(Visited.begin(), Visited.end(), In) == Visited.end());
2698 Visited.push_back(In);
2706 // Groups the instructions to a bundle (which is then a single scheduling entity)
2707 // and schedules instructions until the bundle gets ready.
2708 bool BoUpSLP::BlockScheduling::tryScheduleBundle(ArrayRef<Value *> VL,
2710 if (isa<PHINode>(VL[0]))
2713 // Initialize the instruction bundle.
2714 Instruction *OldScheduleEnd = ScheduleEnd;
2715 ScheduleData *PrevInBundle = nullptr;
2716 ScheduleData *Bundle = nullptr;
2717 bool ReSchedule = false;
2718 DEBUG(dbgs() << "SLP: bundle: " << *VL[0] << "\n");
2720 // Make sure that the scheduling region contains all
2721 // instructions of the bundle.
2722 for (Value *V : VL) {
2723 if (!extendSchedulingRegion(V))
2727 for (Value *V : VL) {
2728 ScheduleData *BundleMember = getScheduleData(V);
2729 assert(BundleMember &&
2730 "no ScheduleData for bundle member (maybe not in same basic block)");
2731 if (BundleMember->IsScheduled) {
2732 // A bundle member was scheduled as single instruction before and now
2733 // needs to be scheduled as part of the bundle. We just get rid of the
2734 // existing schedule.
2735 DEBUG(dbgs() << "SLP: reset schedule because " << *BundleMember
2736 << " was already scheduled\n");
2739 assert(BundleMember->isSchedulingEntity() &&
2740 "bundle member already part of other bundle");
2742 PrevInBundle->NextInBundle = BundleMember;
2744 Bundle = BundleMember;
2746 BundleMember->UnscheduledDepsInBundle = 0;
2747 Bundle->UnscheduledDepsInBundle += BundleMember->UnscheduledDeps;
2749 // Group the instructions to a bundle.
2750 BundleMember->FirstInBundle = Bundle;
2751 PrevInBundle = BundleMember;
2753 if (ScheduleEnd != OldScheduleEnd) {
2754 // The scheduling region got new instructions at the lower end (or it is a
2755 // new region for the first bundle). This makes it necessary to
2756 // recalculate all dependencies.
2757 // It is seldom that this needs to be done a second time after adding the
2758 // initial bundle to the region.
2759 for (auto *I = ScheduleStart; I != ScheduleEnd; I = I->getNextNode()) {
2760 ScheduleData *SD = getScheduleData(I);
2761 SD->clearDependencies();
2767 initialFillReadyList(ReadyInsts);
2770 DEBUG(dbgs() << "SLP: try schedule bundle " << *Bundle << " in block "
2771 << BB->getName() << "\n");
2773 calculateDependencies(Bundle, true, SLP);
2775 // Now try to schedule the new bundle. As soon as the bundle is "ready" it
2776 // means that there are no cyclic dependencies and we can schedule it.
2777 // Note that's important that we don't "schedule" the bundle yet (see
2778 // cancelScheduling).
2779 while (!Bundle->isReady() && !ReadyInsts.empty()) {
2781 ScheduleData *pickedSD = ReadyInsts.back();
2782 ReadyInsts.pop_back();
2784 if (pickedSD->isSchedulingEntity() && pickedSD->isReady()) {
2785 schedule(pickedSD, ReadyInsts);
2788 if (!Bundle->isReady()) {
2789 cancelScheduling(VL);
2795 void BoUpSLP::BlockScheduling::cancelScheduling(ArrayRef<Value *> VL) {
2796 if (isa<PHINode>(VL[0]))
2799 ScheduleData *Bundle = getScheduleData(VL[0]);
2800 DEBUG(dbgs() << "SLP: cancel scheduling of " << *Bundle << "\n");
2801 assert(!Bundle->IsScheduled &&
2802 "Can't cancel bundle which is already scheduled");
2803 assert(Bundle->isSchedulingEntity() && Bundle->isPartOfBundle() &&
2804 "tried to unbundle something which is not a bundle");
2806 // Un-bundle: make single instructions out of the bundle.
2807 ScheduleData *BundleMember = Bundle;
2808 while (BundleMember) {
2809 assert(BundleMember->FirstInBundle == Bundle && "corrupt bundle links");
2810 BundleMember->FirstInBundle = BundleMember;
2811 ScheduleData *Next = BundleMember->NextInBundle;
2812 BundleMember->NextInBundle = nullptr;
2813 BundleMember->UnscheduledDepsInBundle = BundleMember->UnscheduledDeps;
2814 if (BundleMember->UnscheduledDepsInBundle == 0) {
2815 ReadyInsts.insert(BundleMember);
2817 BundleMember = Next;
2821 bool BoUpSLP::BlockScheduling::extendSchedulingRegion(Value *V) {
2822 if (getScheduleData(V))
2824 Instruction *I = dyn_cast<Instruction>(V);
2825 assert(I && "bundle member must be an instruction");
2826 assert(!isa<PHINode>(I) && "phi nodes don't need to be scheduled");
2827 if (!ScheduleStart) {
2828 // It's the first instruction in the new region.
2829 initScheduleData(I, I->getNextNode(), nullptr, nullptr);
2831 ScheduleEnd = I->getNextNode();
2832 assert(ScheduleEnd && "tried to vectorize a TerminatorInst?");
2833 DEBUG(dbgs() << "SLP: initialize schedule region to " << *I << "\n");
2836 // Search up and down at the same time, because we don't know if the new
2837 // instruction is above or below the existing scheduling region.
2838 BasicBlock::reverse_iterator UpIter(ScheduleStart);
2839 BasicBlock::reverse_iterator UpperEnd = BB->rend();
2840 BasicBlock::iterator DownIter(ScheduleEnd);
2841 BasicBlock::iterator LowerEnd = BB->end();
2843 if (++ScheduleRegionSize > ScheduleRegionSizeLimit) {
2844 DEBUG(dbgs() << "SLP: exceeded schedule region size limit\n");
2848 if (UpIter != UpperEnd) {
2849 if (&*UpIter == I) {
2850 initScheduleData(I, ScheduleStart, nullptr, FirstLoadStoreInRegion);
2852 DEBUG(dbgs() << "SLP: extend schedule region start to " << *I << "\n");
2857 if (DownIter != LowerEnd) {
2858 if (&*DownIter == I) {
2859 initScheduleData(ScheduleEnd, I->getNextNode(), LastLoadStoreInRegion,
2861 ScheduleEnd = I->getNextNode();
2862 assert(ScheduleEnd && "tried to vectorize a TerminatorInst?");
2863 DEBUG(dbgs() << "SLP: extend schedule region end to " << *I << "\n");
2868 assert((UpIter != UpperEnd || DownIter != LowerEnd) &&
2869 "instruction not found in block");
2874 void BoUpSLP::BlockScheduling::initScheduleData(Instruction *FromI,
2876 ScheduleData *PrevLoadStore,
2877 ScheduleData *NextLoadStore) {
2878 ScheduleData *CurrentLoadStore = PrevLoadStore;
2879 for (Instruction *I = FromI; I != ToI; I = I->getNextNode()) {
2880 ScheduleData *SD = ScheduleDataMap[I];
2882 // Allocate a new ScheduleData for the instruction.
2883 if (ChunkPos >= ChunkSize) {
2884 ScheduleDataChunks.push_back(
2885 llvm::make_unique<ScheduleData[]>(ChunkSize));
2888 SD = &(ScheduleDataChunks.back()[ChunkPos++]);
2889 ScheduleDataMap[I] = SD;
2892 assert(!isInSchedulingRegion(SD) &&
2893 "new ScheduleData already in scheduling region");
2894 SD->init(SchedulingRegionID);
2896 if (I->mayReadOrWriteMemory()) {
2897 // Update the linked list of memory accessing instructions.
2898 if (CurrentLoadStore) {
2899 CurrentLoadStore->NextLoadStore = SD;
2901 FirstLoadStoreInRegion = SD;
2903 CurrentLoadStore = SD;
2906 if (NextLoadStore) {
2907 if (CurrentLoadStore)
2908 CurrentLoadStore->NextLoadStore = NextLoadStore;
2910 LastLoadStoreInRegion = CurrentLoadStore;
2914 void BoUpSLP::BlockScheduling::calculateDependencies(ScheduleData *SD,
2915 bool InsertInReadyList,
2917 assert(SD->isSchedulingEntity());
2919 SmallVector<ScheduleData *, 10> WorkList;
2920 WorkList.push_back(SD);
2922 while (!WorkList.empty()) {
2923 ScheduleData *SD = WorkList.back();
2924 WorkList.pop_back();
2926 ScheduleData *BundleMember = SD;
2927 while (BundleMember) {
2928 assert(isInSchedulingRegion(BundleMember));
2929 if (!BundleMember->hasValidDependencies()) {
2931 DEBUG(dbgs() << "SLP: update deps of " << *BundleMember << "\n");
2932 BundleMember->Dependencies = 0;
2933 BundleMember->resetUnscheduledDeps();
2935 // Handle def-use chain dependencies.
2936 for (User *U : BundleMember->Inst->users()) {
2937 if (isa<Instruction>(U)) {
2938 ScheduleData *UseSD = getScheduleData(U);
2939 if (UseSD && isInSchedulingRegion(UseSD->FirstInBundle)) {
2940 BundleMember->Dependencies++;
2941 ScheduleData *DestBundle = UseSD->FirstInBundle;
2942 if (!DestBundle->IsScheduled) {
2943 BundleMember->incrementUnscheduledDeps(1);
2945 if (!DestBundle->hasValidDependencies()) {
2946 WorkList.push_back(DestBundle);
2950 // I'm not sure if this can ever happen. But we need to be safe.
2951 // This lets the instruction/bundle never be scheduled and
2952 // eventually disable vectorization.
2953 BundleMember->Dependencies++;
2954 BundleMember->incrementUnscheduledDeps(1);
2958 // Handle the memory dependencies.
2959 ScheduleData *DepDest = BundleMember->NextLoadStore;
2961 Instruction *SrcInst = BundleMember->Inst;
2962 MemoryLocation SrcLoc = getLocation(SrcInst, SLP->AA);
2963 bool SrcMayWrite = BundleMember->Inst->mayWriteToMemory();
2964 unsigned numAliased = 0;
2965 unsigned DistToSrc = 1;
2968 assert(isInSchedulingRegion(DepDest));
2970 // We have two limits to reduce the complexity:
2971 // 1) AliasedCheckLimit: It's a small limit to reduce calls to
2972 // SLP->isAliased (which is the expensive part in this loop).
2973 // 2) MaxMemDepDistance: It's for very large blocks and it aborts
2974 // the whole loop (even if the loop is fast, it's quadratic).
2975 // It's important for the loop break condition (see below) to
2976 // check this limit even between two read-only instructions.
2977 if (DistToSrc >= MaxMemDepDistance ||
2978 ((SrcMayWrite || DepDest->Inst->mayWriteToMemory()) &&
2979 (numAliased >= AliasedCheckLimit ||
2980 SLP->isAliased(SrcLoc, SrcInst, DepDest->Inst)))) {
2982 // We increment the counter only if the locations are aliased
2983 // (instead of counting all alias checks). This gives a better
2984 // balance between reduced runtime and accurate dependencies.
2987 DepDest->MemoryDependencies.push_back(BundleMember);
2988 BundleMember->Dependencies++;
2989 ScheduleData *DestBundle = DepDest->FirstInBundle;
2990 if (!DestBundle->IsScheduled) {
2991 BundleMember->incrementUnscheduledDeps(1);
2993 if (!DestBundle->hasValidDependencies()) {
2994 WorkList.push_back(DestBundle);
2997 DepDest = DepDest->NextLoadStore;
2999 // Example, explaining the loop break condition: Let's assume our
3000 // starting instruction is i0 and MaxMemDepDistance = 3.
3003 // i0,i1,i2,i3,i4,i5,i6,i7,i8
3006 // MaxMemDepDistance let us stop alias-checking at i3 and we add
3007 // dependencies from i0 to i3,i4,.. (even if they are not aliased).
3008 // Previously we already added dependencies from i3 to i6,i7,i8
3009 // (because of MaxMemDepDistance). As we added a dependency from
3010 // i0 to i3, we have transitive dependencies from i0 to i6,i7,i8
3011 // and we can abort this loop at i6.
3012 if (DistToSrc >= 2 * MaxMemDepDistance)
3018 BundleMember = BundleMember->NextInBundle;
3020 if (InsertInReadyList && SD->isReady()) {
3021 ReadyInsts.push_back(SD);
3022 DEBUG(dbgs() << "SLP: gets ready on update: " << *SD->Inst << "\n");
3027 void BoUpSLP::BlockScheduling::resetSchedule() {
3028 assert(ScheduleStart &&
3029 "tried to reset schedule on block which has not been scheduled");
3030 for (Instruction *I = ScheduleStart; I != ScheduleEnd; I = I->getNextNode()) {
3031 ScheduleData *SD = getScheduleData(I);
3032 assert(isInSchedulingRegion(SD));
3033 SD->IsScheduled = false;
3034 SD->resetUnscheduledDeps();
3039 void BoUpSLP::scheduleBlock(BlockScheduling *BS) {
3041 if (!BS->ScheduleStart)
3044 DEBUG(dbgs() << "SLP: schedule block " << BS->BB->getName() << "\n");
3046 BS->resetSchedule();
3048 // For the real scheduling we use a more sophisticated ready-list: it is
3049 // sorted by the original instruction location. This lets the final schedule
3050 // be as close as possible to the original instruction order.
3051 struct ScheduleDataCompare {
3052 bool operator()(ScheduleData *SD1, ScheduleData *SD2) {
3053 return SD2->SchedulingPriority < SD1->SchedulingPriority;
3056 std::set<ScheduleData *, ScheduleDataCompare> ReadyInsts;
3058 // Ensure that all dependency data is updated and fill the ready-list with
3059 // initial instructions.
3061 int NumToSchedule = 0;
3062 for (auto *I = BS->ScheduleStart; I != BS->ScheduleEnd;
3063 I = I->getNextNode()) {
3064 ScheduleData *SD = BS->getScheduleData(I);
3066 SD->isPartOfBundle() == (ScalarToTreeEntry.count(SD->Inst) != 0) &&
3067 "scheduler and vectorizer have different opinion on what is a bundle");
3068 SD->FirstInBundle->SchedulingPriority = Idx++;
3069 if (SD->isSchedulingEntity()) {
3070 BS->calculateDependencies(SD, false, this);
3074 BS->initialFillReadyList(ReadyInsts);
3076 Instruction *LastScheduledInst = BS->ScheduleEnd;
3078 // Do the "real" scheduling.
3079 while (!ReadyInsts.empty()) {
3080 ScheduleData *picked = *ReadyInsts.begin();
3081 ReadyInsts.erase(ReadyInsts.begin());
3083 // Move the scheduled instruction(s) to their dedicated places, if not
3085 ScheduleData *BundleMember = picked;
3086 while (BundleMember) {
3087 Instruction *pickedInst = BundleMember->Inst;
3088 if (LastScheduledInst->getNextNode() != pickedInst) {
3089 BS->BB->getInstList().remove(pickedInst);
3090 BS->BB->getInstList().insert(LastScheduledInst, pickedInst);
3092 LastScheduledInst = pickedInst;
3093 BundleMember = BundleMember->NextInBundle;
3096 BS->schedule(picked, ReadyInsts);
3099 assert(NumToSchedule == 0 && "could not schedule all instructions");
3101 // Avoid duplicate scheduling of the block.
3102 BS->ScheduleStart = nullptr;
3105 /// The SLPVectorizer Pass.
3106 struct SLPVectorizer : public FunctionPass {
3107 typedef SmallVector<StoreInst *, 8> StoreList;
3108 typedef MapVector<Value *, StoreList> StoreListMap;
3110 /// Pass identification, replacement for typeid
3113 explicit SLPVectorizer() : FunctionPass(ID) {
3114 initializeSLPVectorizerPass(*PassRegistry::getPassRegistry());
3117 ScalarEvolution *SE;
3118 TargetTransformInfo *TTI;
3119 TargetLibraryInfo *TLI;
3123 AssumptionCache *AC;
3125 bool runOnFunction(Function &F) override {
3126 if (skipOptnoneFunction(F))
3129 SE = &getAnalysis<ScalarEvolutionWrapperPass>().getSE();
3130 TTI = &getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
3131 auto *TLIP = getAnalysisIfAvailable<TargetLibraryInfoWrapperPass>();
3132 TLI = TLIP ? &TLIP->getTLI() : nullptr;
3133 AA = &getAnalysis<AAResultsWrapperPass>().getAAResults();
3134 LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
3135 DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
3136 AC = &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
3139 bool Changed = false;
3141 // If the target claims to have no vector registers don't attempt
3143 if (!TTI->getNumberOfRegisters(true))
3146 // Use the vector register size specified by the target unless overridden
3147 // by a command-line option.
3148 // TODO: It would be better to limit the vectorization factor based on
3149 // data type rather than just register size. For example, x86 AVX has
3150 // 256-bit registers, but it does not support integer operations
3151 // at that width (that requires AVX2).
3152 if (MaxVectorRegSizeOption.getNumOccurrences())
3153 MaxVecRegSize = MaxVectorRegSizeOption;
3155 MaxVecRegSize = TTI->getRegisterBitWidth(true);
3157 // Don't vectorize when the attribute NoImplicitFloat is used.
3158 if (F.hasFnAttribute(Attribute::NoImplicitFloat))
3161 DEBUG(dbgs() << "SLP: Analyzing blocks in " << F.getName() << ".\n");
3163 // Use the bottom up slp vectorizer to construct chains that start with
3164 // store instructions.
3165 BoUpSLP R(&F, SE, TTI, TLI, AA, LI, DT, AC);
3167 // A general note: the vectorizer must use BoUpSLP::eraseInstruction() to
3168 // delete instructions.
3170 // Scan the blocks in the function in post order.
3171 for (auto BB : post_order(&F.getEntryBlock())) {
3172 // Vectorize trees that end at stores.
3173 if (unsigned count = collectStores(BB, R)) {
3175 DEBUG(dbgs() << "SLP: Found " << count << " stores to vectorize.\n");
3176 Changed |= vectorizeStoreChains(R);
3179 // Vectorize trees that end at reductions.
3180 Changed |= vectorizeChainsInBlock(BB, R);
3184 R.optimizeGatherSequence();
3185 DEBUG(dbgs() << "SLP: vectorized \"" << F.getName() << "\"\n");
3186 DEBUG(verifyFunction(F));
3191 void getAnalysisUsage(AnalysisUsage &AU) const override {
3192 FunctionPass::getAnalysisUsage(AU);
3193 AU.addRequired<AssumptionCacheTracker>();
3194 AU.addRequired<ScalarEvolutionWrapperPass>();
3195 AU.addRequired<AAResultsWrapperPass>();
3196 AU.addRequired<TargetTransformInfoWrapperPass>();
3197 AU.addRequired<LoopInfoWrapperPass>();
3198 AU.addRequired<DominatorTreeWrapperPass>();
3199 AU.addPreserved<LoopInfoWrapperPass>();
3200 AU.addPreserved<DominatorTreeWrapperPass>();
3201 AU.setPreservesCFG();
3206 /// \brief Collect memory references and sort them according to their base
3207 /// object. We sort the stores to their base objects to reduce the cost of the
3208 /// quadratic search on the stores. TODO: We can further reduce this cost
3209 /// if we flush the chain creation every time we run into a memory barrier.
3210 unsigned collectStores(BasicBlock *BB, BoUpSLP &R);
3212 /// \brief Try to vectorize a chain that starts at two arithmetic instrs.
3213 bool tryToVectorizePair(Value *A, Value *B, BoUpSLP &R);
3215 /// \brief Try to vectorize a list of operands.
3216 /// \@param BuildVector A list of users to ignore for the purpose of
3217 /// scheduling and that don't need extracting.
3218 /// \returns true if a value was vectorized.
3219 bool tryToVectorizeList(ArrayRef<Value *> VL, BoUpSLP &R,
3220 ArrayRef<Value *> BuildVector = None,
3221 bool allowReorder = false);
3223 /// \brief Try to vectorize a chain that may start at the operands of \V;
3224 bool tryToVectorize(BinaryOperator *V, BoUpSLP &R);
3226 /// \brief Vectorize the stores that were collected in StoreRefs.
3227 bool vectorizeStoreChains(BoUpSLP &R);
3229 /// \brief Scan the basic block and look for patterns that are likely to start
3230 /// a vectorization chain.
3231 bool vectorizeChainsInBlock(BasicBlock *BB, BoUpSLP &R);
3233 bool vectorizeStoreChain(ArrayRef<Value *> Chain, int CostThreshold,
3234 BoUpSLP &R, unsigned VecRegSize);
3236 bool vectorizeStores(ArrayRef<StoreInst *> Stores, int costThreshold,
3239 StoreListMap StoreRefs;
3240 unsigned MaxVecRegSize; // This is set by TTI or overridden by cl::opt.
3243 /// \brief Check that the Values in the slice in VL array are still existent in
3244 /// the WeakVH array.
3245 /// Vectorization of part of the VL array may cause later values in the VL array
3246 /// to become invalid. We track when this has happened in the WeakVH array.
3247 static bool hasValueBeenRAUWed(ArrayRef<Value *> VL, ArrayRef<WeakVH> VH,
3248 unsigned SliceBegin, unsigned SliceSize) {
3249 VL = VL.slice(SliceBegin, SliceSize);
3250 VH = VH.slice(SliceBegin, SliceSize);
3251 return !std::equal(VL.begin(), VL.end(), VH.begin());
3254 bool SLPVectorizer::vectorizeStoreChain(ArrayRef<Value *> Chain,
3255 int CostThreshold, BoUpSLP &R,
3256 unsigned VecRegSize) {
3257 unsigned ChainLen = Chain.size();
3258 DEBUG(dbgs() << "SLP: Analyzing a store chain of length " << ChainLen
3260 Type *StoreTy = cast<StoreInst>(Chain[0])->getValueOperand()->getType();
3261 auto &DL = cast<StoreInst>(Chain[0])->getModule()->getDataLayout();
3262 unsigned Sz = DL.getTypeSizeInBits(StoreTy);
3263 unsigned VF = VecRegSize / Sz;
3265 if (!isPowerOf2_32(Sz) || VF < 2)
3268 // Keep track of values that were deleted by vectorizing in the loop below.
3269 SmallVector<WeakVH, 8> TrackValues(Chain.begin(), Chain.end());
3271 bool Changed = false;
3272 // Look for profitable vectorizable trees at all offsets, starting at zero.
3273 for (unsigned i = 0, e = ChainLen; i < e; ++i) {
3277 // Check that a previous iteration of this loop did not delete the Value.
3278 if (hasValueBeenRAUWed(Chain, TrackValues, i, VF))
3281 DEBUG(dbgs() << "SLP: Analyzing " << VF << " stores at offset " << i
3283 ArrayRef<Value *> Operands = Chain.slice(i, VF);
3285 R.buildTree(Operands);
3287 int Cost = R.getTreeCost();
3289 DEBUG(dbgs() << "SLP: Found cost=" << Cost << " for VF=" << VF << "\n");
3290 if (Cost < CostThreshold) {
3291 DEBUG(dbgs() << "SLP: Decided to vectorize cost=" << Cost << "\n");
3294 // Move to the next bundle.
3303 bool SLPVectorizer::vectorizeStores(ArrayRef<StoreInst *> Stores,
3304 int costThreshold, BoUpSLP &R) {
3305 SetVector<StoreInst *> Heads, Tails;
3306 SmallDenseMap<StoreInst *, StoreInst *> ConsecutiveChain;
3308 // We may run into multiple chains that merge into a single chain. We mark the
3309 // stores that we vectorized so that we don't visit the same store twice.
3310 BoUpSLP::ValueSet VectorizedStores;
3311 bool Changed = false;
3313 // Do a quadratic search on all of the given stores and find
3314 // all of the pairs of stores that follow each other.
3315 SmallVector<unsigned, 16> IndexQueue;
3316 for (unsigned i = 0, e = Stores.size(); i < e; ++i) {
3317 const DataLayout &DL = Stores[i]->getModule()->getDataLayout();
3319 // If a store has multiple consecutive store candidates, search Stores
3320 // array according to the sequence: from i+1 to e, then from i-1 to 0.
3321 // This is because usually pairing with immediate succeeding or preceding
3322 // candidate create the best chance to find slp vectorization opportunity.
3324 for (j = i + 1; j < e; ++j)
3325 IndexQueue.push_back(j);
3326 for (j = i; j > 0; --j)
3327 IndexQueue.push_back(j - 1);
3329 for (auto &k : IndexQueue) {
3330 if (R.isConsecutiveAccess(Stores[i], Stores[k], DL)) {
3331 Tails.insert(Stores[k]);
3332 Heads.insert(Stores[i]);
3333 ConsecutiveChain[Stores[i]] = Stores[k];
3339 // For stores that start but don't end a link in the chain:
3340 for (SetVector<StoreInst *>::iterator it = Heads.begin(), e = Heads.end();
3342 if (Tails.count(*it))
3345 // We found a store instr that starts a chain. Now follow the chain and try
3347 BoUpSLP::ValueList Operands;
3349 // Collect the chain into a list.
3350 while (Tails.count(I) || Heads.count(I)) {
3351 if (VectorizedStores.count(I))
3353 Operands.push_back(I);
3354 // Move to the next value in the chain.
3355 I = ConsecutiveChain[I];
3358 // FIXME: Is division-by-2 the correct step? Should we assert that the
3359 // register size is a power-of-2?
3360 for (unsigned Size = MaxVecRegSize; Size >= MinVecRegSize; Size /= 2) {
3361 if (vectorizeStoreChain(Operands, costThreshold, R, Size)) {
3362 // Mark the vectorized stores so that we don't vectorize them again.
3363 VectorizedStores.insert(Operands.begin(), Operands.end());
3374 unsigned SLPVectorizer::collectStores(BasicBlock *BB, BoUpSLP &R) {
3377 const DataLayout &DL = BB->getModule()->getDataLayout();
3378 for (Instruction &I : *BB) {
3379 StoreInst *SI = dyn_cast<StoreInst>(&I);
3383 // Don't touch volatile stores.
3384 if (!SI->isSimple())
3387 // Check that the pointer points to scalars.
3388 Type *Ty = SI->getValueOperand()->getType();
3389 if (!isValidElementType(Ty))
3392 // Find the base pointer.
3393 Value *Ptr = GetUnderlyingObject(SI->getPointerOperand(), DL);
3395 // Save the store locations.
3396 StoreRefs[Ptr].push_back(SI);
3402 bool SLPVectorizer::tryToVectorizePair(Value *A, Value *B, BoUpSLP &R) {
3405 Value *VL[] = { A, B };
3406 return tryToVectorizeList(VL, R, None, true);
3409 bool SLPVectorizer::tryToVectorizeList(ArrayRef<Value *> VL, BoUpSLP &R,
3410 ArrayRef<Value *> BuildVector,
3411 bool allowReorder) {
3415 DEBUG(dbgs() << "SLP: Vectorizing a list of length = " << VL.size() << ".\n");
3417 // Check that all of the parts are scalar instructions of the same type.
3418 Instruction *I0 = dyn_cast<Instruction>(VL[0]);
3422 unsigned Opcode0 = I0->getOpcode();
3423 const DataLayout &DL = I0->getModule()->getDataLayout();
3425 Type *Ty0 = I0->getType();
3426 unsigned Sz = DL.getTypeSizeInBits(Ty0);
3427 // FIXME: Register size should be a parameter to this function, so we can
3428 // try different vectorization factors.
3429 unsigned VF = MinVecRegSize / Sz;
3431 for (Value *V : VL) {
3432 Type *Ty = V->getType();
3433 if (!isValidElementType(Ty))
3435 Instruction *Inst = dyn_cast<Instruction>(V);
3436 if (!Inst || Inst->getOpcode() != Opcode0)
3440 bool Changed = false;
3442 // Keep track of values that were deleted by vectorizing in the loop below.
3443 SmallVector<WeakVH, 8> TrackValues(VL.begin(), VL.end());
3445 for (unsigned i = 0, e = VL.size(); i < e; ++i) {
3446 unsigned OpsWidth = 0;
3453 if (!isPowerOf2_32(OpsWidth) || OpsWidth < 2)
3456 // Check that a previous iteration of this loop did not delete the Value.
3457 if (hasValueBeenRAUWed(VL, TrackValues, i, OpsWidth))
3460 DEBUG(dbgs() << "SLP: Analyzing " << OpsWidth << " operations "
3462 ArrayRef<Value *> Ops = VL.slice(i, OpsWidth);
3464 ArrayRef<Value *> BuildVectorSlice;
3465 if (!BuildVector.empty())
3466 BuildVectorSlice = BuildVector.slice(i, OpsWidth);
3468 R.buildTree(Ops, BuildVectorSlice);
3469 // TODO: check if we can allow reordering also for other cases than
3470 // tryToVectorizePair()
3471 if (allowReorder && R.shouldReorder()) {
3472 assert(Ops.size() == 2);
3473 assert(BuildVectorSlice.empty());
3474 Value *ReorderedOps[] = { Ops[1], Ops[0] };
3475 R.buildTree(ReorderedOps, None);
3477 int Cost = R.getTreeCost();
3479 if (Cost < -SLPCostThreshold) {
3480 DEBUG(dbgs() << "SLP: Vectorizing list at cost:" << Cost << ".\n");
3481 Value *VectorizedRoot = R.vectorizeTree();
3483 // Reconstruct the build vector by extracting the vectorized root. This
3484 // way we handle the case where some elements of the vector are undefined.
3485 // (return (inserelt <4 xi32> (insertelt undef (opd0) 0) (opd1) 2))
3486 if (!BuildVectorSlice.empty()) {
3487 // The insert point is the last build vector instruction. The vectorized
3488 // root will precede it. This guarantees that we get an instruction. The
3489 // vectorized tree could have been constant folded.
3490 Instruction *InsertAfter = cast<Instruction>(BuildVectorSlice.back());
3491 unsigned VecIdx = 0;
3492 for (auto &V : BuildVectorSlice) {
3493 IRBuilder<true, NoFolder> Builder(
3494 ++BasicBlock::iterator(InsertAfter));
3495 InsertElementInst *IE = cast<InsertElementInst>(V);
3496 Instruction *Extract = cast<Instruction>(Builder.CreateExtractElement(
3497 VectorizedRoot, Builder.getInt32(VecIdx++)));
3498 IE->setOperand(1, Extract);
3499 IE->removeFromParent();
3500 IE->insertAfter(Extract);
3504 // Move to the next bundle.
3513 bool SLPVectorizer::tryToVectorize(BinaryOperator *V, BoUpSLP &R) {
3517 // Try to vectorize V.
3518 if (tryToVectorizePair(V->getOperand(0), V->getOperand(1), R))
3521 BinaryOperator *A = dyn_cast<BinaryOperator>(V->getOperand(0));
3522 BinaryOperator *B = dyn_cast<BinaryOperator>(V->getOperand(1));
3524 if (B && B->hasOneUse()) {
3525 BinaryOperator *B0 = dyn_cast<BinaryOperator>(B->getOperand(0));
3526 BinaryOperator *B1 = dyn_cast<BinaryOperator>(B->getOperand(1));
3527 if (tryToVectorizePair(A, B0, R)) {
3530 if (tryToVectorizePair(A, B1, R)) {
3536 if (A && A->hasOneUse()) {
3537 BinaryOperator *A0 = dyn_cast<BinaryOperator>(A->getOperand(0));
3538 BinaryOperator *A1 = dyn_cast<BinaryOperator>(A->getOperand(1));
3539 if (tryToVectorizePair(A0, B, R)) {
3542 if (tryToVectorizePair(A1, B, R)) {
3549 /// \brief Generate a shuffle mask to be used in a reduction tree.
3551 /// \param VecLen The length of the vector to be reduced.
3552 /// \param NumEltsToRdx The number of elements that should be reduced in the
3554 /// \param IsPairwise Whether the reduction is a pairwise or splitting
3555 /// reduction. A pairwise reduction will generate a mask of
3556 /// <0,2,...> or <1,3,..> while a splitting reduction will generate
3557 /// <2,3, undef,undef> for a vector of 4 and NumElts = 2.
3558 /// \param IsLeft True will generate a mask of even elements, odd otherwise.
3559 static Value *createRdxShuffleMask(unsigned VecLen, unsigned NumEltsToRdx,
3560 bool IsPairwise, bool IsLeft,
3561 IRBuilder<> &Builder) {
3562 assert((IsPairwise || !IsLeft) && "Don't support a <0,1,undef,...> mask");
3564 SmallVector<Constant *, 32> ShuffleMask(
3565 VecLen, UndefValue::get(Builder.getInt32Ty()));
3568 // Build a mask of 0, 2, ... (left) or 1, 3, ... (right).
3569 for (unsigned i = 0; i != NumEltsToRdx; ++i)
3570 ShuffleMask[i] = Builder.getInt32(2 * i + !IsLeft);
3572 // Move the upper half of the vector to the lower half.
3573 for (unsigned i = 0; i != NumEltsToRdx; ++i)
3574 ShuffleMask[i] = Builder.getInt32(NumEltsToRdx + i);
3576 return ConstantVector::get(ShuffleMask);
3580 /// Model horizontal reductions.
3582 /// A horizontal reduction is a tree of reduction operations (currently add and
3583 /// fadd) that has operations that can be put into a vector as its leaf.
3584 /// For example, this tree:
3591 /// This tree has "mul" as its reduced values and "+" as its reduction
3592 /// operations. A reduction might be feeding into a store or a binary operation
3607 class HorizontalReduction {
3608 SmallVector<Value *, 16> ReductionOps;
3609 SmallVector<Value *, 32> ReducedVals;
3611 BinaryOperator *ReductionRoot;
3612 PHINode *ReductionPHI;
3614 /// The opcode of the reduction.
3615 unsigned ReductionOpcode;
3616 /// The opcode of the values we perform a reduction on.
3617 unsigned ReducedValueOpcode;
3618 /// The width of one full horizontal reduction operation.
3619 unsigned ReduxWidth;
3620 /// Should we model this reduction as a pairwise reduction tree or a tree that
3621 /// splits the vector in halves and adds those halves.
3622 bool IsPairwiseReduction;
3625 HorizontalReduction()
3626 : ReductionRoot(nullptr), ReductionPHI(nullptr), ReductionOpcode(0),
3627 ReducedValueOpcode(0), ReduxWidth(0), IsPairwiseReduction(false) {}
3629 /// \brief Try to find a reduction tree.
3630 bool matchAssociativeReduction(PHINode *Phi, BinaryOperator *B) {
3632 std::find(Phi->op_begin(), Phi->op_end(), B) != Phi->op_end()) &&
3633 "Thi phi needs to use the binary operator");
3635 // We could have a initial reductions that is not an add.
3636 // r *= v1 + v2 + v3 + v4
3637 // In such a case start looking for a tree rooted in the first '+'.
3639 if (B->getOperand(0) == Phi) {
3641 B = dyn_cast<BinaryOperator>(B->getOperand(1));
3642 } else if (B->getOperand(1) == Phi) {
3644 B = dyn_cast<BinaryOperator>(B->getOperand(0));
3651 Type *Ty = B->getType();
3652 if (!isValidElementType(Ty))
3655 const DataLayout &DL = B->getModule()->getDataLayout();
3656 ReductionOpcode = B->getOpcode();
3657 ReducedValueOpcode = 0;
3658 // FIXME: Register size should be a parameter to this function, so we can
3659 // try different vectorization factors.
3660 ReduxWidth = MinVecRegSize / DL.getTypeSizeInBits(Ty);
3667 // We currently only support adds.
3668 if (ReductionOpcode != Instruction::Add &&
3669 ReductionOpcode != Instruction::FAdd)
3672 // Post order traverse the reduction tree starting at B. We only handle true
3673 // trees containing only binary operators.
3674 SmallVector<std::pair<BinaryOperator *, unsigned>, 32> Stack;
3675 Stack.push_back(std::make_pair(B, 0));
3676 while (!Stack.empty()) {
3677 BinaryOperator *TreeN = Stack.back().first;
3678 unsigned EdgeToVist = Stack.back().second++;
3679 bool IsReducedValue = TreeN->getOpcode() != ReductionOpcode;
3681 // Only handle trees in the current basic block.
3682 if (TreeN->getParent() != B->getParent())
3685 // Each tree node needs to have one user except for the ultimate
3687 if (!TreeN->hasOneUse() && TreeN != B)
3691 if (EdgeToVist == 2 || IsReducedValue) {
3692 if (IsReducedValue) {
3693 // Make sure that the opcodes of the operations that we are going to
3695 if (!ReducedValueOpcode)
3696 ReducedValueOpcode = TreeN->getOpcode();
3697 else if (ReducedValueOpcode != TreeN->getOpcode())
3699 ReducedVals.push_back(TreeN);
3701 // We need to be able to reassociate the adds.
3702 if (!TreeN->isAssociative())
3704 ReductionOps.push_back(TreeN);
3711 // Visit left or right.
3712 Value *NextV = TreeN->getOperand(EdgeToVist);
3713 BinaryOperator *Next = dyn_cast<BinaryOperator>(NextV);
3715 Stack.push_back(std::make_pair(Next, 0));
3716 else if (NextV != Phi)
3722 /// \brief Attempt to vectorize the tree found by
3723 /// matchAssociativeReduction.
3724 bool tryToReduce(BoUpSLP &V, TargetTransformInfo *TTI) {
3725 if (ReducedVals.empty())
3728 unsigned NumReducedVals = ReducedVals.size();
3729 if (NumReducedVals < ReduxWidth)
3732 Value *VectorizedTree = nullptr;
3733 IRBuilder<> Builder(ReductionRoot);
3734 FastMathFlags Unsafe;
3735 Unsafe.setUnsafeAlgebra();
3736 Builder.SetFastMathFlags(Unsafe);
3739 for (; i < NumReducedVals - ReduxWidth + 1; i += ReduxWidth) {
3740 V.buildTree(makeArrayRef(&ReducedVals[i], ReduxWidth), ReductionOps);
3743 int Cost = V.getTreeCost() + getReductionCost(TTI, ReducedVals[i]);
3744 if (Cost >= -SLPCostThreshold)
3747 DEBUG(dbgs() << "SLP: Vectorizing horizontal reduction at cost:" << Cost
3750 // Vectorize a tree.
3751 DebugLoc Loc = cast<Instruction>(ReducedVals[i])->getDebugLoc();
3752 Value *VectorizedRoot = V.vectorizeTree();
3754 // Emit a reduction.
3755 Value *ReducedSubTree = emitReduction(VectorizedRoot, Builder);
3756 if (VectorizedTree) {
3757 Builder.SetCurrentDebugLocation(Loc);
3758 VectorizedTree = createBinOp(Builder, ReductionOpcode, VectorizedTree,
3759 ReducedSubTree, "bin.rdx");
3761 VectorizedTree = ReducedSubTree;
3764 if (VectorizedTree) {
3765 // Finish the reduction.
3766 for (; i < NumReducedVals; ++i) {
3767 Builder.SetCurrentDebugLocation(
3768 cast<Instruction>(ReducedVals[i])->getDebugLoc());
3769 VectorizedTree = createBinOp(Builder, ReductionOpcode, VectorizedTree,
3774 assert(ReductionRoot && "Need a reduction operation");
3775 ReductionRoot->setOperand(0, VectorizedTree);
3776 ReductionRoot->setOperand(1, ReductionPHI);
3778 ReductionRoot->replaceAllUsesWith(VectorizedTree);
3780 return VectorizedTree != nullptr;
3785 /// \brief Calculate the cost of a reduction.
3786 int getReductionCost(TargetTransformInfo *TTI, Value *FirstReducedVal) {
3787 Type *ScalarTy = FirstReducedVal->getType();
3788 Type *VecTy = VectorType::get(ScalarTy, ReduxWidth);
3790 int PairwiseRdxCost = TTI->getReductionCost(ReductionOpcode, VecTy, true);
3791 int SplittingRdxCost = TTI->getReductionCost(ReductionOpcode, VecTy, false);
3793 IsPairwiseReduction = PairwiseRdxCost < SplittingRdxCost;
3794 int VecReduxCost = IsPairwiseReduction ? PairwiseRdxCost : SplittingRdxCost;
3796 int ScalarReduxCost =
3797 ReduxWidth * TTI->getArithmeticInstrCost(ReductionOpcode, VecTy);
3799 DEBUG(dbgs() << "SLP: Adding cost " << VecReduxCost - ScalarReduxCost
3800 << " for reduction that starts with " << *FirstReducedVal
3802 << (IsPairwiseReduction ? "pairwise" : "splitting")
3803 << " reduction)\n");
3805 return VecReduxCost - ScalarReduxCost;
3808 static Value *createBinOp(IRBuilder<> &Builder, unsigned Opcode, Value *L,
3809 Value *R, const Twine &Name = "") {
3810 if (Opcode == Instruction::FAdd)
3811 return Builder.CreateFAdd(L, R, Name);
3812 return Builder.CreateBinOp((Instruction::BinaryOps)Opcode, L, R, Name);
3815 /// \brief Emit a horizontal reduction of the vectorized value.
3816 Value *emitReduction(Value *VectorizedValue, IRBuilder<> &Builder) {
3817 assert(VectorizedValue && "Need to have a vectorized tree node");
3818 assert(isPowerOf2_32(ReduxWidth) &&
3819 "We only handle power-of-two reductions for now");
3821 Value *TmpVec = VectorizedValue;
3822 for (unsigned i = ReduxWidth / 2; i != 0; i >>= 1) {
3823 if (IsPairwiseReduction) {
3825 createRdxShuffleMask(ReduxWidth, i, true, true, Builder);
3827 createRdxShuffleMask(ReduxWidth, i, true, false, Builder);
3829 Value *LeftShuf = Builder.CreateShuffleVector(
3830 TmpVec, UndefValue::get(TmpVec->getType()), LeftMask, "rdx.shuf.l");
3831 Value *RightShuf = Builder.CreateShuffleVector(
3832 TmpVec, UndefValue::get(TmpVec->getType()), (RightMask),
3834 TmpVec = createBinOp(Builder, ReductionOpcode, LeftShuf, RightShuf,
3838 createRdxShuffleMask(ReduxWidth, i, false, false, Builder);
3839 Value *Shuf = Builder.CreateShuffleVector(
3840 TmpVec, UndefValue::get(TmpVec->getType()), UpperHalf, "rdx.shuf");
3841 TmpVec = createBinOp(Builder, ReductionOpcode, TmpVec, Shuf, "bin.rdx");
3845 // The result is in the first element of the vector.
3846 return Builder.CreateExtractElement(TmpVec, Builder.getInt32(0));
3850 /// \brief Recognize construction of vectors like
3851 /// %ra = insertelement <4 x float> undef, float %s0, i32 0
3852 /// %rb = insertelement <4 x float> %ra, float %s1, i32 1
3853 /// %rc = insertelement <4 x float> %rb, float %s2, i32 2
3854 /// %rd = insertelement <4 x float> %rc, float %s3, i32 3
3856 /// Returns true if it matches
3858 static bool findBuildVector(InsertElementInst *FirstInsertElem,
3859 SmallVectorImpl<Value *> &BuildVector,
3860 SmallVectorImpl<Value *> &BuildVectorOpds) {
3861 if (!isa<UndefValue>(FirstInsertElem->getOperand(0)))
3864 InsertElementInst *IE = FirstInsertElem;
3866 BuildVector.push_back(IE);
3867 BuildVectorOpds.push_back(IE->getOperand(1));
3869 if (IE->use_empty())
3872 InsertElementInst *NextUse = dyn_cast<InsertElementInst>(IE->user_back());
3876 // If this isn't the final use, make sure the next insertelement is the only
3877 // use. It's OK if the final constructed vector is used multiple times
3878 if (!IE->hasOneUse())
3887 static bool PhiTypeSorterFunc(Value *V, Value *V2) {
3888 return V->getType() < V2->getType();
3891 bool SLPVectorizer::vectorizeChainsInBlock(BasicBlock *BB, BoUpSLP &R) {
3892 bool Changed = false;
3893 SmallVector<Value *, 4> Incoming;
3894 SmallSet<Value *, 16> VisitedInstrs;
3896 bool HaveVectorizedPhiNodes = true;
3897 while (HaveVectorizedPhiNodes) {
3898 HaveVectorizedPhiNodes = false;
3900 // Collect the incoming values from the PHIs.
3902 for (BasicBlock::iterator instr = BB->begin(), ie = BB->end(); instr != ie;
3904 PHINode *P = dyn_cast<PHINode>(instr);
3908 if (!VisitedInstrs.count(P))
3909 Incoming.push_back(P);
3913 std::stable_sort(Incoming.begin(), Incoming.end(), PhiTypeSorterFunc);
3915 // Try to vectorize elements base on their type.
3916 for (SmallVector<Value *, 4>::iterator IncIt = Incoming.begin(),
3920 // Look for the next elements with the same type.
3921 SmallVector<Value *, 4>::iterator SameTypeIt = IncIt;
3922 while (SameTypeIt != E &&
3923 (*SameTypeIt)->getType() == (*IncIt)->getType()) {
3924 VisitedInstrs.insert(*SameTypeIt);
3928 // Try to vectorize them.
3929 unsigned NumElts = (SameTypeIt - IncIt);
3930 DEBUG(errs() << "SLP: Trying to vectorize starting at PHIs (" << NumElts << ")\n");
3931 if (NumElts > 1 && tryToVectorizeList(makeArrayRef(IncIt, NumElts), R)) {
3932 // Success start over because instructions might have been changed.
3933 HaveVectorizedPhiNodes = true;
3938 // Start over at the next instruction of a different type (or the end).
3943 VisitedInstrs.clear();
3945 for (BasicBlock::iterator it = BB->begin(), e = BB->end(); it != e; it++) {
3946 // We may go through BB multiple times so skip the one we have checked.
3947 if (!VisitedInstrs.insert(it).second)
3950 if (isa<DbgInfoIntrinsic>(it))
3953 // Try to vectorize reductions that use PHINodes.
3954 if (PHINode *P = dyn_cast<PHINode>(it)) {
3955 // Check that the PHI is a reduction PHI.
3956 if (P->getNumIncomingValues() != 2)
3959 (P->getIncomingBlock(0) == BB
3960 ? (P->getIncomingValue(0))
3961 : (P->getIncomingBlock(1) == BB ? P->getIncomingValue(1)
3963 // Check if this is a Binary Operator.
3964 BinaryOperator *BI = dyn_cast_or_null<BinaryOperator>(Rdx);
3968 // Try to match and vectorize a horizontal reduction.
3969 HorizontalReduction HorRdx;
3970 if (ShouldVectorizeHor && HorRdx.matchAssociativeReduction(P, BI) &&
3971 HorRdx.tryToReduce(R, TTI)) {
3978 Value *Inst = BI->getOperand(0);
3980 Inst = BI->getOperand(1);
3982 if (tryToVectorize(dyn_cast<BinaryOperator>(Inst), R)) {
3983 // We would like to start over since some instructions are deleted
3984 // and the iterator may become invalid value.
3994 // Try to vectorize horizontal reductions feeding into a store.
3995 if (ShouldStartVectorizeHorAtStore)
3996 if (StoreInst *SI = dyn_cast<StoreInst>(it))
3997 if (BinaryOperator *BinOp =
3998 dyn_cast<BinaryOperator>(SI->getValueOperand())) {
3999 HorizontalReduction HorRdx;
4000 if (((HorRdx.matchAssociativeReduction(nullptr, BinOp) &&
4001 HorRdx.tryToReduce(R, TTI)) ||
4002 tryToVectorize(BinOp, R))) {
4010 // Try to vectorize horizontal reductions feeding into a return.
4011 if (ReturnInst *RI = dyn_cast<ReturnInst>(it))
4012 if (RI->getNumOperands() != 0)
4013 if (BinaryOperator *BinOp =
4014 dyn_cast<BinaryOperator>(RI->getOperand(0))) {
4015 DEBUG(dbgs() << "SLP: Found a return to vectorize.\n");
4016 if (tryToVectorizePair(BinOp->getOperand(0),
4017 BinOp->getOperand(1), R)) {
4025 // Try to vectorize trees that start at compare instructions.
4026 if (CmpInst *CI = dyn_cast<CmpInst>(it)) {
4027 if (tryToVectorizePair(CI->getOperand(0), CI->getOperand(1), R)) {
4029 // We would like to start over since some instructions are deleted
4030 // and the iterator may become invalid value.
4036 for (int i = 0; i < 2; ++i) {
4037 if (BinaryOperator *BI = dyn_cast<BinaryOperator>(CI->getOperand(i))) {
4038 if (tryToVectorizePair(BI->getOperand(0), BI->getOperand(1), R)) {
4040 // We would like to start over since some instructions are deleted
4041 // and the iterator may become invalid value.
4051 // Try to vectorize trees that start at insertelement instructions.
4052 if (InsertElementInst *FirstInsertElem = dyn_cast<InsertElementInst>(it)) {
4053 SmallVector<Value *, 16> BuildVector;
4054 SmallVector<Value *, 16> BuildVectorOpds;
4055 if (!findBuildVector(FirstInsertElem, BuildVector, BuildVectorOpds))
4058 // Vectorize starting with the build vector operands ignoring the
4059 // BuildVector instructions for the purpose of scheduling and user
4061 if (tryToVectorizeList(BuildVectorOpds, R, BuildVector)) {
4074 bool SLPVectorizer::vectorizeStoreChains(BoUpSLP &R) {
4075 bool Changed = false;
4076 // Attempt to sort and vectorize each of the store-groups.
4077 for (StoreListMap::iterator it = StoreRefs.begin(), e = StoreRefs.end();
4079 if (it->second.size() < 2)
4082 DEBUG(dbgs() << "SLP: Analyzing a store chain of length "
4083 << it->second.size() << ".\n");
4085 // Process the stores in chunks of 16.
4086 // TODO: The limit of 16 inhibits greater vectorization factors.
4087 // For example, AVX2 supports v32i8. Increasing this limit, however,
4088 // may cause a significant compile-time increase.
4089 for (unsigned CI = 0, CE = it->second.size(); CI < CE; CI+=16) {
4090 unsigned Len = std::min<unsigned>(CE - CI, 16);
4091 Changed |= vectorizeStores(makeArrayRef(&it->second[CI], Len),
4092 -SLPCostThreshold, R);
4098 } // end anonymous namespace
4100 char SLPVectorizer::ID = 0;
4101 static const char lv_name[] = "SLP Vectorizer";
4102 INITIALIZE_PASS_BEGIN(SLPVectorizer, SV_NAME, lv_name, false, false)
4103 INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)
4104 INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)
4105 INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)
4106 INITIALIZE_PASS_DEPENDENCY(ScalarEvolutionWrapperPass)
4107 INITIALIZE_PASS_DEPENDENCY(LoopSimplify)
4108 INITIALIZE_PASS_END(SLPVectorizer, SV_NAME, lv_name, false, false)
4111 Pass *createSLPVectorizerPass() { return new SLPVectorizer(); }