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-rw-r--r--contrib/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp2529
1 files changed, 2423 insertions, 106 deletions
diff --git a/contrib/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp b/contrib/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
index cc30cc9..c72b51f 100644
--- a/contrib/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/contrib/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -16,18 +16,23 @@
//
//===----------------------------------------------------------------------===//
#define SV_NAME "slp-vectorizer"
-#define DEBUG_TYPE SV_NAME
+#define DEBUG_TYPE "SLP"
-#include "VecUtils.h"
#include "llvm/Transforms/Vectorize.h"
+#include "llvm/ADT/MapVector.h"
+#include "llvm/ADT/PostOrderIterator.h"
+#include "llvm/ADT/SetVector.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/ScalarEvolution.h"
+#include "llvm/Analysis/ScalarEvolutionExpressions.h"
#include "llvm/Analysis/TargetTransformInfo.h"
+#include "llvm/Analysis/ValueTracking.h"
#include "llvm/Analysis/Verifier.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/Value.h"
@@ -35,19 +40,1717 @@
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
#include <map>
using namespace llvm;
static cl::opt<int>
-SLPCostThreshold("slp-threshold", cl::init(0), cl::Hidden,
- cl::desc("Only vectorize trees if the gain is above this "
- "number. (gain = -cost of vectorization)"));
+ SLPCostThreshold("slp-threshold", cl::init(0), cl::Hidden,
+ cl::desc("Only vectorize if you gain more than this "
+ "number "));
+
+static cl::opt<bool>
+ShouldVectorizeHor("slp-vectorize-hor", cl::init(false), cl::Hidden,
+ cl::desc("Attempt to vectorize horizontal reductions"));
+
+static cl::opt<bool> ShouldStartVectorizeHorAtStore(
+ "slp-vectorize-hor-store", cl::init(false), cl::Hidden,
+ cl::desc(
+ "Attempt to vectorize horizontal reductions feeding into a store"));
+
namespace {
+static const unsigned MinVecRegSize = 128;
+
+static const unsigned RecursionMaxDepth = 12;
+
+/// A helper class for numbering instructions in multiple blocks.
+/// Numbers start at zero for each basic block.
+struct BlockNumbering {
+
+ BlockNumbering(BasicBlock *Bb) : BB(Bb), Valid(false) {}
+
+ BlockNumbering() : BB(0), Valid(false) {}
+
+ void numberInstructions() {
+ unsigned Loc = 0;
+ InstrIdx.clear();
+ InstrVec.clear();
+ // Number the instructions in the block.
+ for (BasicBlock::iterator it = BB->begin(), e = BB->end(); it != e; ++it) {
+ InstrIdx[it] = Loc++;
+ InstrVec.push_back(it);
+ assert(InstrVec[InstrIdx[it]] == it && "Invalid allocation");
+ }
+ Valid = true;
+ }
+
+ int getIndex(Instruction *I) {
+ assert(I->getParent() == BB && "Invalid instruction");
+ if (!Valid)
+ numberInstructions();
+ assert(InstrIdx.count(I) && "Unknown instruction");
+ return InstrIdx[I];
+ }
+
+ Instruction *getInstruction(unsigned loc) {
+ if (!Valid)
+ numberInstructions();
+ assert(InstrVec.size() > loc && "Invalid Index");
+ return InstrVec[loc];
+ }
+
+ void forget() { Valid = false; }
+
+private:
+ /// The block we are numbering.
+ BasicBlock *BB;
+ /// Is the block numbered.
+ bool Valid;
+ /// Maps instructions to numbers and back.
+ SmallDenseMap<Instruction *, int> InstrIdx;
+ /// Maps integers to Instructions.
+ SmallVector<Instruction *, 32> InstrVec;
+};
+
+/// \returns the parent basic block if all of the instructions in \p VL
+/// are in the same block or null otherwise.
+static BasicBlock *getSameBlock(ArrayRef<Value *> VL) {
+ Instruction *I0 = dyn_cast<Instruction>(VL[0]);
+ if (!I0)
+ return 0;
+ BasicBlock *BB = I0->getParent();
+ for (int i = 1, e = VL.size(); i < e; i++) {
+ Instruction *I = dyn_cast<Instruction>(VL[i]);
+ if (!I)
+ return 0;
+
+ if (BB != I->getParent())
+ return 0;
+ }
+ return BB;
+}
+
+/// \returns True if all of the values in \p VL are constants.
+static bool allConstant(ArrayRef<Value *> VL) {
+ for (unsigned i = 0, e = VL.size(); i < e; ++i)
+ if (!isa<Constant>(VL[i]))
+ return false;
+ return true;
+}
+
+/// \returns True if all of the values in \p VL are identical.
+static bool isSplat(ArrayRef<Value *> VL) {
+ for (unsigned i = 1, e = VL.size(); i < e; ++i)
+ if (VL[i] != VL[0])
+ return false;
+ return true;
+}
+
+/// \returns The opcode if all of the Instructions in \p VL have the same
+/// opcode, or zero.
+static unsigned getSameOpcode(ArrayRef<Value *> VL) {
+ Instruction *I0 = dyn_cast<Instruction>(VL[0]);
+ if (!I0)
+ return 0;
+ unsigned Opcode = I0->getOpcode();
+ for (int i = 1, e = VL.size(); i < e; i++) {
+ Instruction *I = dyn_cast<Instruction>(VL[i]);
+ if (!I || Opcode != I->getOpcode())
+ return 0;
+ }
+ return Opcode;
+}
+
+/// \returns \p I after propagating metadata from \p VL.
+static Instruction *propagateMetadata(Instruction *I, ArrayRef<Value *> VL) {
+ Instruction *I0 = cast<Instruction>(VL[0]);
+ SmallVector<std::pair<unsigned, MDNode *>, 4> Metadata;
+ I0->getAllMetadataOtherThanDebugLoc(Metadata);
+
+ for (unsigned i = 0, n = Metadata.size(); i != n; ++i) {
+ unsigned Kind = Metadata[i].first;
+ MDNode *MD = Metadata[i].second;
+
+ for (int i = 1, e = VL.size(); MD && i != e; i++) {
+ Instruction *I = cast<Instruction>(VL[i]);
+ MDNode *IMD = I->getMetadata(Kind);
+
+ switch (Kind) {
+ default:
+ MD = 0; // Remove unknown metadata
+ break;
+ case LLVMContext::MD_tbaa:
+ MD = MDNode::getMostGenericTBAA(MD, IMD);
+ break;
+ case LLVMContext::MD_fpmath:
+ MD = MDNode::getMostGenericFPMath(MD, IMD);
+ break;
+ }
+ }
+ I->setMetadata(Kind, MD);
+ }
+ return I;
+}
+
+/// \returns The type that all of the values in \p VL have or null if there
+/// are different types.
+static Type* getSameType(ArrayRef<Value *> VL) {
+ Type *Ty = VL[0]->getType();
+ for (int i = 1, e = VL.size(); i < e; i++)
+ if (VL[i]->getType() != Ty)
+ return 0;
+
+ return Ty;
+}
+
+/// \returns True if the ExtractElement instructions in VL can be vectorized
+/// to use the original vector.
+static bool CanReuseExtract(ArrayRef<Value *> VL) {
+ assert(Instruction::ExtractElement == getSameOpcode(VL) && "Invalid opcode");
+ // Check if all of the extracts come from the same vector and from the
+ // correct offset.
+ Value *VL0 = VL[0];
+ ExtractElementInst *E0 = cast<ExtractElementInst>(VL0);
+ Value *Vec = E0->getOperand(0);
+
+ // We have to extract from the same vector type.
+ unsigned NElts = Vec->getType()->getVectorNumElements();
+
+ if (NElts != VL.size())
+ return false;
+
+ // Check that all of the indices extract from the correct offset.
+ ConstantInt *CI = dyn_cast<ConstantInt>(E0->getOperand(1));
+ if (!CI || CI->getZExtValue())
+ return false;
+
+ for (unsigned i = 1, e = VL.size(); i < e; ++i) {
+ ExtractElementInst *E = cast<ExtractElementInst>(VL[i]);
+ ConstantInt *CI = dyn_cast<ConstantInt>(E->getOperand(1));
+
+ if (!CI || CI->getZExtValue() != i || E->getOperand(0) != Vec)
+ return false;
+ }
+
+ return true;
+}
+
+static void reorderInputsAccordingToOpcode(ArrayRef<Value *> VL,
+ SmallVectorImpl<Value *> &Left,
+ SmallVectorImpl<Value *> &Right) {
+
+ SmallVector<Value *, 16> OrigLeft, OrigRight;
+
+ bool AllSameOpcodeLeft = true;
+ bool AllSameOpcodeRight = true;
+ for (unsigned i = 0, e = VL.size(); i != e; ++i) {
+ Instruction *I = cast<Instruction>(VL[i]);
+ Value *V0 = I->getOperand(0);
+ Value *V1 = I->getOperand(1);
+
+ OrigLeft.push_back(V0);
+ OrigRight.push_back(V1);
+
+ Instruction *I0 = dyn_cast<Instruction>(V0);
+ Instruction *I1 = dyn_cast<Instruction>(V1);
+
+ // Check whether all operands on one side have the same opcode. In this case
+ // we want to preserve the original order and not make things worse by
+ // reordering.
+ AllSameOpcodeLeft = I0;
+ AllSameOpcodeRight = I1;
+
+ if (i && AllSameOpcodeLeft) {
+ if(Instruction *P0 = dyn_cast<Instruction>(OrigLeft[i-1])) {
+ if(P0->getOpcode() != I0->getOpcode())
+ AllSameOpcodeLeft = false;
+ } else
+ AllSameOpcodeLeft = false;
+ }
+ if (i && AllSameOpcodeRight) {
+ if(Instruction *P1 = dyn_cast<Instruction>(OrigRight[i-1])) {
+ if(P1->getOpcode() != I1->getOpcode())
+ AllSameOpcodeRight = false;
+ } else
+ AllSameOpcodeRight = false;
+ }
+
+ // Sort two opcodes. In the code below we try to preserve the ability to use
+ // broadcast of values instead of individual inserts.
+ // vl1 = load
+ // vl2 = phi
+ // vr1 = load
+ // vr2 = vr2
+ // = vl1 x vr1
+ // = vl2 x vr2
+ // If we just sorted according to opcode we would leave the first line in
+ // tact but we would swap vl2 with vr2 because opcode(phi) > opcode(load).
+ // = vl1 x vr1
+ // = vr2 x vl2
+ // Because vr2 and vr1 are from the same load we loose the opportunity of a
+ // broadcast for the packed right side in the backend: we have [vr1, vl2]
+ // instead of [vr1, vr2=vr1].
+ if (I0 && I1) {
+ if(!i && I0->getOpcode() > I1->getOpcode()) {
+ Left.push_back(I1);
+ Right.push_back(I0);
+ } else if (i && I0->getOpcode() > I1->getOpcode() && Right[i-1] != I1) {
+ // Try not to destroy a broad cast for no apparent benefit.
+ Left.push_back(I1);
+ Right.push_back(I0);
+ } else if (i && I0->getOpcode() == I1->getOpcode() && Right[i-1] == I0) {
+ // Try preserve broadcasts.
+ Left.push_back(I1);
+ Right.push_back(I0);
+ } else if (i && I0->getOpcode() == I1->getOpcode() && Left[i-1] == I1) {
+ // Try preserve broadcasts.
+ Left.push_back(I1);
+ Right.push_back(I0);
+ } else {
+ Left.push_back(I0);
+ Right.push_back(I1);
+ }
+ continue;
+ }
+ // One opcode, put the instruction on the right.
+ if (I0) {
+ Left.push_back(V1);
+ Right.push_back(I0);
+ continue;
+ }
+ Left.push_back(V0);
+ Right.push_back(V1);
+ }
+
+ bool LeftBroadcast = isSplat(Left);
+ bool RightBroadcast = isSplat(Right);
+
+ // Don't reorder if the operands where good to begin with.
+ if (!(LeftBroadcast || RightBroadcast) &&
+ (AllSameOpcodeRight || AllSameOpcodeLeft)) {
+ Left = OrigLeft;
+ Right = OrigRight;
+ }
+}
+
+/// Bottom Up SLP Vectorizer.
+class BoUpSLP {
+public:
+ typedef SmallVector<Value *, 8> ValueList;
+ typedef SmallVector<Instruction *, 16> InstrList;
+ typedef SmallPtrSet<Value *, 16> ValueSet;
+ typedef SmallVector<StoreInst *, 8> StoreList;
+
+ BoUpSLP(Function *Func, ScalarEvolution *Se, DataLayout *Dl,
+ TargetTransformInfo *Tti, AliasAnalysis *Aa, LoopInfo *Li,
+ DominatorTree *Dt) :
+ F(Func), SE(Se), DL(Dl), TTI(Tti), AA(Aa), LI(Li), DT(Dt),
+ Builder(Se->getContext()) {
+ // Setup the block numbering utility for all of the blocks in the
+ // function.
+ for (Function::iterator it = F->begin(), e = F->end(); it != e; ++it) {
+ BasicBlock *BB = it;
+ BlocksNumbers[BB] = BlockNumbering(BB);
+ }
+ }
+
+ /// \brief Vectorize the tree that starts with the elements in \p VL.
+ /// Returns the vectorized root.
+ Value *vectorizeTree();
+
+ /// \returns the vectorization cost of the subtree that starts at \p VL.
+ /// A negative number means that this is profitable.
+ int getTreeCost();
+
+ /// Construct a vectorizable tree that starts at \p Roots and is possibly
+ /// used by a reduction of \p RdxOps.
+ void buildTree(ArrayRef<Value *> Roots, ValueSet *RdxOps = 0);
+
+ /// Clear the internal data structures that are created by 'buildTree'.
+ void deleteTree() {
+ RdxOps = 0;
+ VectorizableTree.clear();
+ ScalarToTreeEntry.clear();
+ MustGather.clear();
+ ExternalUses.clear();
+ MemBarrierIgnoreList.clear();
+ }
+
+ /// \returns true if the memory operations A and B are consecutive.
+ bool isConsecutiveAccess(Value *A, Value *B);
+
+ /// \brief Perform LICM and CSE on the newly generated gather sequences.
+ void optimizeGatherSequence();
+private:
+ struct TreeEntry;
+
+ /// \returns the cost of the vectorizable entry.
+ int getEntryCost(TreeEntry *E);
+
+ /// This is the recursive part of buildTree.
+ void buildTree_rec(ArrayRef<Value *> Roots, unsigned Depth);
+
+ /// Vectorize a single entry in the tree.
+ Value *vectorizeTree(TreeEntry *E);
+
+ /// Vectorize a single entry in the tree, starting in \p VL.
+ Value *vectorizeTree(ArrayRef<Value *> VL);
+
+ /// \returns the pointer to the vectorized value if \p VL is already
+ /// vectorized, or NULL. They may happen in cycles.
+ Value *alreadyVectorized(ArrayRef<Value *> VL) const;
+
+ /// \brief Take the pointer operand from the Load/Store instruction.
+ /// \returns NULL if this is not a valid Load/Store instruction.
+ static Value *getPointerOperand(Value *I);
+
+ /// \brief Take the address space operand from the Load/Store instruction.
+ /// \returns -1 if this is not a valid Load/Store instruction.
+ static unsigned getAddressSpaceOperand(Value *I);
+
+ /// \returns the scalarization cost for this type. Scalarization in this
+ /// context means the creation of vectors from a group of scalars.
+ int getGatherCost(Type *Ty);
+
+ /// \returns the scalarization cost for this list of values. Assuming that
+ /// this subtree gets vectorized, we may need to extract the values from the
+ /// roots. This method calculates the cost of extracting the values.
+ int getGatherCost(ArrayRef<Value *> VL);
+
+ /// \returns the AA location that is being access by the instruction.
+ AliasAnalysis::Location getLocation(Instruction *I);
+
+ /// \brief Checks if it is possible to sink an instruction from
+ /// \p Src to \p Dst.
+ /// \returns the pointer to the barrier instruction if we can't sink.
+ Value *getSinkBarrier(Instruction *Src, Instruction *Dst);
+
+ /// \returns the index of the last instruction in the BB from \p VL.
+ int getLastIndex(ArrayRef<Value *> VL);
+
+ /// \returns the Instruction in the bundle \p VL.
+ Instruction *getLastInstruction(ArrayRef<Value *> VL);
+
+ /// \brief Set the Builder insert point to one after the last instruction in
+ /// the bundle
+ void setInsertPointAfterBundle(ArrayRef<Value *> VL);
+
+ /// \returns a vector from a collection of scalars in \p VL.
+ Value *Gather(ArrayRef<Value *> VL, VectorType *Ty);
+
+ /// \returns whether the VectorizableTree is fully vectoriable and will
+ /// be beneficial even the tree height is tiny.
+ bool isFullyVectorizableTinyTree();
+
+ struct TreeEntry {
+ TreeEntry() : Scalars(), VectorizedValue(0), LastScalarIndex(0),
+ NeedToGather(0) {}
+
+ /// \returns true if the scalars in VL are equal to this entry.
+ bool isSame(ArrayRef<Value *> VL) const {
+ assert(VL.size() == Scalars.size() && "Invalid size");
+ return std::equal(VL.begin(), VL.end(), Scalars.begin());
+ }
+
+ /// A vector of scalars.
+ ValueList Scalars;
+
+ /// The Scalars are vectorized into this value. It is initialized to Null.
+ Value *VectorizedValue;
+
+ /// The index in the basic block of the last scalar.
+ int LastScalarIndex;
+
+ /// Do we need to gather this sequence ?
+ bool NeedToGather;
+ };
+
+ /// Create a new VectorizableTree entry.
+ TreeEntry *newTreeEntry(ArrayRef<Value *> VL, bool Vectorized) {
+ VectorizableTree.push_back(TreeEntry());
+ int idx = VectorizableTree.size() - 1;
+ TreeEntry *Last = &VectorizableTree[idx];
+ Last->Scalars.insert(Last->Scalars.begin(), VL.begin(), VL.end());
+ Last->NeedToGather = !Vectorized;
+ if (Vectorized) {
+ Last->LastScalarIndex = getLastIndex(VL);
+ for (int i = 0, e = VL.size(); i != e; ++i) {
+ assert(!ScalarToTreeEntry.count(VL[i]) && "Scalar already in tree!");
+ ScalarToTreeEntry[VL[i]] = idx;
+ }
+ } else {
+ Last->LastScalarIndex = 0;
+ MustGather.insert(VL.begin(), VL.end());
+ }
+ return Last;
+ }
+
+ /// -- Vectorization State --
+ /// Holds all of the tree entries.
+ std::vector<TreeEntry> VectorizableTree;
+
+ /// Maps a specific scalar to its tree entry.
+ SmallDenseMap<Value*, int> ScalarToTreeEntry;
+
+ /// A list of scalars that we found that we need to keep as scalars.
+ ValueSet MustGather;
+
+ /// This POD struct describes one external user in the vectorized tree.
+ struct ExternalUser {
+ ExternalUser (Value *S, llvm::User *U, int L) :
+ Scalar(S), User(U), Lane(L){};
+ // Which scalar in our function.
+ Value *Scalar;
+ // Which user that uses the scalar.
+ llvm::User *User;
+ // Which lane does the scalar belong to.
+ int Lane;
+ };
+ typedef SmallVector<ExternalUser, 16> UserList;
+
+ /// A list of values that need to extracted out of the tree.
+ /// This list holds pairs of (Internal Scalar : External User).
+ UserList ExternalUses;
+
+ /// A list of instructions to ignore while sinking
+ /// memory instructions. This map must be reset between runs of getCost.
+ ValueSet MemBarrierIgnoreList;
+
+ /// Holds all of the instructions that we gathered.
+ SetVector<Instruction *> GatherSeq;
+ /// A list of blocks that we are going to CSE.
+ SmallSet<BasicBlock *, 8> CSEBlocks;
+
+ /// Numbers instructions in different blocks.
+ DenseMap<BasicBlock *, BlockNumbering> BlocksNumbers;
+
+ /// Reduction operators.
+ ValueSet *RdxOps;
+
+ // Analysis and block reference.
+ Function *F;
+ ScalarEvolution *SE;
+ DataLayout *DL;
+ TargetTransformInfo *TTI;
+ AliasAnalysis *AA;
+ LoopInfo *LI;
+ DominatorTree *DT;
+ /// Instruction builder to construct the vectorized tree.
+ IRBuilder<> Builder;
+};
+
+void BoUpSLP::buildTree(ArrayRef<Value *> Roots, ValueSet *Rdx) {
+ deleteTree();
+ RdxOps = Rdx;
+ if (!getSameType(Roots))
+ return;
+ buildTree_rec(Roots, 0);
+
+ // Collect the values that we need to extract from the tree.
+ for (int EIdx = 0, EE = VectorizableTree.size(); EIdx < EE; ++EIdx) {
+ TreeEntry *Entry = &VectorizableTree[EIdx];
+
+ // For each lane:
+ for (int Lane = 0, LE = Entry->Scalars.size(); Lane != LE; ++Lane) {
+ Value *Scalar = Entry->Scalars[Lane];
+
+ // No need to handle users of gathered values.
+ if (Entry->NeedToGather)
+ continue;
+
+ for (Value::use_iterator User = Scalar->use_begin(),
+ UE = Scalar->use_end(); User != UE; ++User) {
+ DEBUG(dbgs() << "SLP: Checking user:" << **User << ".\n");
+
+ // Skip in-tree scalars that become vectors.
+ if (ScalarToTreeEntry.count(*User)) {
+ DEBUG(dbgs() << "SLP: \tInternal user will be removed:" <<
+ **User << ".\n");
+ int Idx = ScalarToTreeEntry[*User]; (void) Idx;
+ assert(!VectorizableTree[Idx].NeedToGather && "Bad state");
+ continue;
+ }
+ Instruction *UserInst = dyn_cast<Instruction>(*User);
+ if (!UserInst)
+ continue;
+
+ // Ignore uses that are part of the reduction.
+ if (Rdx && std::find(Rdx->begin(), Rdx->end(), UserInst) != Rdx->end())
+ continue;
+
+ DEBUG(dbgs() << "SLP: Need to extract:" << **User << " from lane " <<
+ Lane << " from " << *Scalar << ".\n");
+ ExternalUses.push_back(ExternalUser(Scalar, *User, Lane));
+ }
+ }
+ }
+}
+
+
+void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
+ bool SameTy = getSameType(VL); (void)SameTy;
+ assert(SameTy && "Invalid types!");
+
+ if (Depth == RecursionMaxDepth) {
+ DEBUG(dbgs() << "SLP: Gathering due to max recursion depth.\n");
+ newTreeEntry(VL, false);
+ return;
+ }
+
+ // Don't handle vectors.
+ if (VL[0]->getType()->isVectorTy()) {
+ DEBUG(dbgs() << "SLP: Gathering due to vector type.\n");
+ newTreeEntry(VL, false);
+ return;
+ }
+
+ if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
+ if (SI->getValueOperand()->getType()->isVectorTy()) {
+ DEBUG(dbgs() << "SLP: Gathering due to store vector type.\n");
+ newTreeEntry(VL, false);
+ return;
+ }
+
+ // If all of the operands are identical or constant we have a simple solution.
+ if (allConstant(VL) || isSplat(VL) || !getSameBlock(VL) ||
+ !getSameOpcode(VL)) {
+ DEBUG(dbgs() << "SLP: Gathering due to C,S,B,O. \n");
+ newTreeEntry(VL, false);
+ return;
+ }
+
+ // We now know that this is a vector of instructions of the same type from
+ // the same block.
+
+ // Check if this is a duplicate of another entry.
+ if (ScalarToTreeEntry.count(VL[0])) {
+ int Idx = ScalarToTreeEntry[VL[0]];
+ TreeEntry *E = &VectorizableTree[Idx];
+ for (unsigned i = 0, e = VL.size(); i != e; ++i) {
+ DEBUG(dbgs() << "SLP: \tChecking bundle: " << *VL[i] << ".\n");
+ if (E->Scalars[i] != VL[i]) {
+ DEBUG(dbgs() << "SLP: Gathering due to partial overlap.\n");
+ newTreeEntry(VL, false);
+ return;
+ }
+ }
+ DEBUG(dbgs() << "SLP: Perfect diamond merge at " << *VL[0] << ".\n");
+ return;
+ }
+
+ // Check that none of the instructions in the bundle are already in the tree.
+ for (unsigned i = 0, e = VL.size(); i != e; ++i) {
+ if (ScalarToTreeEntry.count(VL[i])) {
+ DEBUG(dbgs() << "SLP: The instruction (" << *VL[i] <<
+ ") is already in tree.\n");
+ newTreeEntry(VL, false);
+ return;
+ }
+ }
+
+ // If any of the scalars appears in the table OR it is marked as a value that
+ // needs to stat scalar then we need to gather the scalars.
+ for (unsigned i = 0, e = VL.size(); i != e; ++i) {
+ if (ScalarToTreeEntry.count(VL[i]) || MustGather.count(VL[i])) {
+ DEBUG(dbgs() << "SLP: Gathering due to gathered scalar. \n");
+ newTreeEntry(VL, false);
+ return;
+ }
+ }
+
+ // Check that all of the users of the scalars that we want to vectorize are
+ // schedulable.
+ Instruction *VL0 = cast<Instruction>(VL[0]);
+ int MyLastIndex = getLastIndex(VL);
+ BasicBlock *BB = cast<Instruction>(VL0)->getParent();
+
+ for (unsigned i = 0, e = VL.size(); i != e; ++i) {
+ Instruction *Scalar = cast<Instruction>(VL[i]);
+ DEBUG(dbgs() << "SLP: Checking users of " << *Scalar << ". \n");
+ for (Value::use_iterator U = Scalar->use_begin(), UE = Scalar->use_end();
+ U != UE; ++U) {
+ DEBUG(dbgs() << "SLP: \tUser " << **U << ". \n");
+ Instruction *User = dyn_cast<Instruction>(*U);
+ if (!User) {
+ DEBUG(dbgs() << "SLP: Gathering due unknown user. \n");
+ newTreeEntry(VL, false);
+ return;
+ }
+
+ // We don't care if the user is in a different basic block.
+ BasicBlock *UserBlock = User->getParent();
+ if (UserBlock != BB) {
+ DEBUG(dbgs() << "SLP: User from a different basic block "
+ << *User << ". \n");
+ continue;
+ }
+
+ // If this is a PHINode within this basic block then we can place the
+ // extract wherever we want.
+ if (isa<PHINode>(*User)) {
+ DEBUG(dbgs() << "SLP: \tWe can schedule PHIs:" << *User << ". \n");
+ continue;
+ }
+
+ // Check if this is a safe in-tree user.
+ if (ScalarToTreeEntry.count(User)) {
+ int Idx = ScalarToTreeEntry[User];
+ int VecLocation = VectorizableTree[Idx].LastScalarIndex;
+ if (VecLocation <= MyLastIndex) {
+ DEBUG(dbgs() << "SLP: Gathering due to unschedulable vector. \n");
+ newTreeEntry(VL, false);
+ return;
+ }
+ DEBUG(dbgs() << "SLP: In-tree user (" << *User << ") at #" <<
+ VecLocation << " vector value (" << *Scalar << ") at #"
+ << MyLastIndex << ".\n");
+ continue;
+ }
+
+ // This user is part of the reduction.
+ if (RdxOps && RdxOps->count(User))
+ continue;
+
+ // Make sure that we can schedule this unknown user.
+ BlockNumbering &BN = BlocksNumbers[BB];
+ int UserIndex = BN.getIndex(User);
+ if (UserIndex < MyLastIndex) {
+
+ DEBUG(dbgs() << "SLP: Can't schedule extractelement for "
+ << *User << ". \n");
+ newTreeEntry(VL, false);
+ return;
+ }
+ }
+ }
+
+ // Check that every instructions appears once in this bundle.
+ for (unsigned i = 0, e = VL.size(); i < e; ++i)
+ for (unsigned j = i+1; j < e; ++j)
+ if (VL[i] == VL[j]) {
+ DEBUG(dbgs() << "SLP: Scalar used twice in bundle.\n");
+ newTreeEntry(VL, false);
+ return;
+ }
+
+ // Check that instructions in this bundle don't reference other instructions.
+ // The runtime of this check is O(N * N-1 * uses(N)) and a typical N is 4.
+ for (unsigned i = 0, e = VL.size(); i < e; ++i) {
+ for (Value::use_iterator U = VL[i]->use_begin(), UE = VL[i]->use_end();
+ U != UE; ++U) {
+ for (unsigned j = 0; j < e; ++j) {
+ if (i != j && *U == VL[j]) {
+ DEBUG(dbgs() << "SLP: Intra-bundle dependencies!" << **U << ". \n");
+ newTreeEntry(VL, false);
+ return;
+ }
+ }
+ }
+ }
+
+ DEBUG(dbgs() << "SLP: We are able to schedule this bundle.\n");
+
+ unsigned Opcode = getSameOpcode(VL);
+
+ // Check if it is safe to sink the loads or the stores.
+ if (Opcode == Instruction::Load || Opcode == Instruction::Store) {
+ Instruction *Last = getLastInstruction(VL);
+
+ for (unsigned i = 0, e = VL.size(); i < e; ++i) {
+ if (VL[i] == Last)
+ continue;
+ Value *Barrier = getSinkBarrier(cast<Instruction>(VL[i]), Last);
+ if (Barrier) {
+ DEBUG(dbgs() << "SLP: Can't sink " << *VL[i] << "\n down to " << *Last
+ << "\n because of " << *Barrier << ". Gathering.\n");
+ newTreeEntry(VL, false);
+ return;
+ }
+ }
+ }
+
+ switch (Opcode) {
+ case Instruction::PHI: {
+ PHINode *PH = dyn_cast<PHINode>(VL0);
+
+ // Check for terminator values (e.g. invoke).
+ for (unsigned j = 0; j < VL.size(); ++j)
+ for (unsigned i = 0, e = PH->getNumIncomingValues(); i < e; ++i) {
+ TerminatorInst *Term = dyn_cast<TerminatorInst>(cast<PHINode>(VL[j])->getIncomingValue(i));
+ if (Term) {
+ DEBUG(dbgs() << "SLP: Need to swizzle PHINodes (TerminatorInst use).\n");
+ newTreeEntry(VL, false);
+ return;
+ }
+ }
+
+ newTreeEntry(VL, true);
+ DEBUG(dbgs() << "SLP: added a vector of PHINodes.\n");
+
+ for (unsigned i = 0, e = PH->getNumIncomingValues(); i < e; ++i) {
+ ValueList Operands;
+ // Prepare the operand vector.
+ for (unsigned j = 0; j < VL.size(); ++j)
+ Operands.push_back(cast<PHINode>(VL[j])->getIncomingValue(i));
+
+ buildTree_rec(Operands, Depth + 1);
+ }
+ return;
+ }
+ case Instruction::ExtractElement: {
+ bool Reuse = CanReuseExtract(VL);
+ if (Reuse) {
+ DEBUG(dbgs() << "SLP: Reusing extract sequence.\n");
+ }
+ newTreeEntry(VL, Reuse);
+ return;
+ }
+ case Instruction::Load: {
+ // Check if the loads are consecutive or of we need to swizzle them.
+ for (unsigned i = 0, e = VL.size() - 1; i < e; ++i) {
+ LoadInst *L = cast<LoadInst>(VL[i]);
+ if (!L->isSimple() || !isConsecutiveAccess(VL[i], VL[i + 1])) {
+ newTreeEntry(VL, false);
+ DEBUG(dbgs() << "SLP: Need to swizzle loads.\n");
+ return;
+ }
+ }
+ newTreeEntry(VL, true);
+ DEBUG(dbgs() << "SLP: added a vector of loads.\n");
+ return;
+ }
+ case Instruction::ZExt:
+ case Instruction::SExt:
+ case Instruction::FPToUI:
+ case Instruction::FPToSI:
+ case Instruction::FPExt:
+ case Instruction::PtrToInt:
+ case Instruction::IntToPtr:
+ case Instruction::SIToFP:
+ case Instruction::UIToFP:
+ case Instruction::Trunc:
+ case Instruction::FPTrunc:
+ case Instruction::BitCast: {
+ Type *SrcTy = VL0->getOperand(0)->getType();
+ for (unsigned i = 0; i < VL.size(); ++i) {
+ Type *Ty = cast<Instruction>(VL[i])->getOperand(0)->getType();
+ if (Ty != SrcTy || Ty->isAggregateType() || Ty->isVectorTy()) {
+ newTreeEntry(VL, false);
+ DEBUG(dbgs() << "SLP: Gathering casts with different src types.\n");
+ return;
+ }
+ }
+ newTreeEntry(VL, true);
+ DEBUG(dbgs() << "SLP: added a vector of casts.\n");
+
+ for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
+ ValueList Operands;
+ // Prepare the operand vector.
+ for (unsigned j = 0; j < VL.size(); ++j)
+ Operands.push_back(cast<Instruction>(VL[j])->getOperand(i));
+
+ buildTree_rec(Operands, Depth+1);
+ }
+ return;
+ }
+ case Instruction::ICmp:
+ case Instruction::FCmp: {
+ // Check that all of the compares have the same predicate.
+ CmpInst::Predicate P0 = dyn_cast<CmpInst>(VL0)->getPredicate();
+ Type *ComparedTy = cast<Instruction>(VL[0])->getOperand(0)->getType();
+ for (unsigned i = 1, e = VL.size(); i < e; ++i) {
+ CmpInst *Cmp = cast<CmpInst>(VL[i]);
+ if (Cmp->getPredicate() != P0 ||
+ Cmp->getOperand(0)->getType() != ComparedTy) {
+ newTreeEntry(VL, false);
+ DEBUG(dbgs() << "SLP: Gathering cmp with different predicate.\n");
+ return;
+ }
+ }
+
+ newTreeEntry(VL, true);
+ DEBUG(dbgs() << "SLP: added a vector of compares.\n");
+
+ for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
+ ValueList Operands;
+ // Prepare the operand vector.
+ for (unsigned j = 0; j < VL.size(); ++j)
+ Operands.push_back(cast<Instruction>(VL[j])->getOperand(i));
+
+ buildTree_rec(Operands, Depth+1);
+ }
+ return;
+ }
+ case Instruction::Select:
+ case Instruction::Add:
+ case Instruction::FAdd:
+ case Instruction::Sub:
+ case Instruction::FSub:
+ case Instruction::Mul:
+ case Instruction::FMul:
+ case Instruction::UDiv:
+ case Instruction::SDiv:
+ case Instruction::FDiv:
+ case Instruction::URem:
+ case Instruction::SRem:
+ case Instruction::FRem:
+ case Instruction::Shl:
+ case Instruction::LShr:
+ case Instruction::AShr:
+ case Instruction::And:
+ case Instruction::Or:
+ case Instruction::Xor: {
+ newTreeEntry(VL, true);
+ DEBUG(dbgs() << "SLP: added a vector of bin op.\n");
+
+ // Sort operands of the instructions so that each side is more likely to
+ // have the same opcode.
+ if (isa<BinaryOperator>(VL0) && VL0->isCommutative()) {
+ ValueList Left, Right;
+ reorderInputsAccordingToOpcode(VL, Left, Right);
+ buildTree_rec(Left, Depth + 1);
+ buildTree_rec(Right, Depth + 1);
+ return;
+ }
+
+ for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
+ ValueList Operands;
+ // Prepare the operand vector.
+ for (unsigned j = 0; j < VL.size(); ++j)
+ Operands.push_back(cast<Instruction>(VL[j])->getOperand(i));
+
+ buildTree_rec(Operands, Depth+1);
+ }
+ return;
+ }
+ case Instruction::Store: {
+ // Check if the stores are consecutive or of we need to swizzle them.
+ for (unsigned i = 0, e = VL.size() - 1; i < e; ++i)
+ if (!isConsecutiveAccess(VL[i], VL[i + 1])) {
+ newTreeEntry(VL, false);
+ DEBUG(dbgs() << "SLP: Non consecutive store.\n");
+ return;
+ }
+
+ newTreeEntry(VL, true);
+ DEBUG(dbgs() << "SLP: added a vector of stores.\n");
+
+ ValueList Operands;
+ for (unsigned j = 0; j < VL.size(); ++j)
+ Operands.push_back(cast<Instruction>(VL[j])->getOperand(0));
+
+ // We can ignore these values because we are sinking them down.
+ MemBarrierIgnoreList.insert(VL.begin(), VL.end());
+ buildTree_rec(Operands, Depth + 1);
+ return;
+ }
+ default:
+ newTreeEntry(VL, false);
+ DEBUG(dbgs() << "SLP: Gathering unknown instruction.\n");
+ return;
+ }
+}
+
+int BoUpSLP::getEntryCost(TreeEntry *E) {
+ ArrayRef<Value*> VL = E->Scalars;
+
+ Type *ScalarTy = VL[0]->getType();
+ if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
+ ScalarTy = SI->getValueOperand()->getType();
+ VectorType *VecTy = VectorType::get(ScalarTy, VL.size());
+
+ if (E->NeedToGather) {
+ if (allConstant(VL))
+ return 0;
+ if (isSplat(VL)) {
+ return TTI->getShuffleCost(TargetTransformInfo::SK_Broadcast, VecTy, 0);
+ }
+ return getGatherCost(E->Scalars);
+ }
+
+ assert(getSameOpcode(VL) && getSameType(VL) && getSameBlock(VL) &&
+ "Invalid VL");
+ Instruction *VL0 = cast<Instruction>(VL[0]);
+ unsigned Opcode = VL0->getOpcode();
+ switch (Opcode) {
+ case Instruction::PHI: {
+ return 0;
+ }
+ case Instruction::ExtractElement: {
+ if (CanReuseExtract(VL))
+ return 0;
+ return getGatherCost(VecTy);
+ }
+ case Instruction::ZExt:
+ case Instruction::SExt:
+ case Instruction::FPToUI:
+ case Instruction::FPToSI:
+ case Instruction::FPExt:
+ case Instruction::PtrToInt:
+ case Instruction::IntToPtr:
+ case Instruction::SIToFP:
+ case Instruction::UIToFP:
+ case Instruction::Trunc:
+ case Instruction::FPTrunc:
+ case Instruction::BitCast: {
+ Type *SrcTy = VL0->getOperand(0)->getType();
+
+ // Calculate the cost of this instruction.
+ int ScalarCost = VL.size() * TTI->getCastInstrCost(VL0->getOpcode(),
+ VL0->getType(), SrcTy);
+
+ VectorType *SrcVecTy = VectorType::get(SrcTy, VL.size());
+ int VecCost = TTI->getCastInstrCost(VL0->getOpcode(), VecTy, SrcVecTy);
+ return VecCost - ScalarCost;
+ }
+ case Instruction::FCmp:
+ case Instruction::ICmp:
+ case Instruction::Select:
+ case Instruction::Add:
+ case Instruction::FAdd:
+ case Instruction::Sub:
+ case Instruction::FSub:
+ case Instruction::Mul:
+ case Instruction::FMul:
+ case Instruction::UDiv:
+ case Instruction::SDiv:
+ case Instruction::FDiv:
+ case Instruction::URem:
+ case Instruction::SRem:
+ case Instruction::FRem:
+ case Instruction::Shl:
+ case Instruction::LShr:
+ case Instruction::AShr:
+ case Instruction::And:
+ case Instruction::Or:
+ case Instruction::Xor: {
+ // Calculate the cost of this instruction.
+ int ScalarCost = 0;
+ int VecCost = 0;
+ if (Opcode == Instruction::FCmp || Opcode == Instruction::ICmp ||
+ Opcode == Instruction::Select) {
+ VectorType *MaskTy = VectorType::get(Builder.getInt1Ty(), VL.size());
+ ScalarCost = VecTy->getNumElements() *
+ TTI->getCmpSelInstrCost(Opcode, ScalarTy, Builder.getInt1Ty());
+ VecCost = TTI->getCmpSelInstrCost(Opcode, VecTy, MaskTy);
+ } else {
+ // Certain instructions can be cheaper to vectorize if they have a
+ // constant second vector operand.
+ TargetTransformInfo::OperandValueKind Op1VK =
+ TargetTransformInfo::OK_AnyValue;
+ TargetTransformInfo::OperandValueKind Op2VK =
+ TargetTransformInfo::OK_UniformConstantValue;
+
+ // Check whether all second operands are constant.
+ for (unsigned i = 0; i < VL.size(); ++i)
+ if (!isa<ConstantInt>(cast<Instruction>(VL[i])->getOperand(1))) {
+ Op2VK = TargetTransformInfo::OK_AnyValue;
+ break;
+ }
+
+ ScalarCost =
+ VecTy->getNumElements() *
+ TTI->getArithmeticInstrCost(Opcode, ScalarTy, Op1VK, Op2VK);
+ VecCost = TTI->getArithmeticInstrCost(Opcode, VecTy, Op1VK, Op2VK);
+ }
+ return VecCost - ScalarCost;
+ }
+ case Instruction::Load: {
+ // Cost of wide load - cost of scalar loads.
+ int ScalarLdCost = VecTy->getNumElements() *
+ TTI->getMemoryOpCost(Instruction::Load, ScalarTy, 1, 0);
+ int VecLdCost = TTI->getMemoryOpCost(Instruction::Load, VecTy, 1, 0);
+ return VecLdCost - ScalarLdCost;
+ }
+ case Instruction::Store: {
+ // We know that we can merge the stores. Calculate the cost.
+ int ScalarStCost = VecTy->getNumElements() *
+ TTI->getMemoryOpCost(Instruction::Store, ScalarTy, 1, 0);
+ int VecStCost = TTI->getMemoryOpCost(Instruction::Store, VecTy, 1, 0);
+ return VecStCost - ScalarStCost;
+ }
+ default:
+ llvm_unreachable("Unknown instruction");
+ }
+}
+
+bool BoUpSLP::isFullyVectorizableTinyTree() {
+ DEBUG(dbgs() << "SLP: Check whether the tree with height " <<
+ VectorizableTree.size() << " is fully vectorizable .\n");
+
+ // We only handle trees of height 2.
+ if (VectorizableTree.size() != 2)
+ return false;
+
+ // Gathering cost would be too much for tiny trees.
+ if (VectorizableTree[0].NeedToGather || VectorizableTree[1].NeedToGather)
+ return false;
+
+ return true;
+}
+
+int BoUpSLP::getTreeCost() {
+ int Cost = 0;
+ DEBUG(dbgs() << "SLP: Calculating cost for tree of size " <<
+ VectorizableTree.size() << ".\n");
+
+ // We only vectorize tiny trees if it is fully vectorizable.
+ if (VectorizableTree.size() < 3 && !isFullyVectorizableTinyTree()) {
+ if (!VectorizableTree.size()) {
+ assert(!ExternalUses.size() && "We should not have any external users");
+ }
+ return INT_MAX;
+ }
+
+ unsigned BundleWidth = VectorizableTree[0].Scalars.size();
+
+ for (unsigned i = 0, e = VectorizableTree.size(); i != e; ++i) {
+ int C = getEntryCost(&VectorizableTree[i]);
+ DEBUG(dbgs() << "SLP: Adding cost " << C << " for bundle that starts with "
+ << *VectorizableTree[i].Scalars[0] << " .\n");
+ Cost += C;
+ }
+
+ int ExtractCost = 0;
+ for (UserList::iterator I = ExternalUses.begin(), E = ExternalUses.end();
+ I != E; ++I) {
+
+ VectorType *VecTy = VectorType::get(I->Scalar->getType(), BundleWidth);
+ ExtractCost += TTI->getVectorInstrCost(Instruction::ExtractElement, VecTy,
+ I->Lane);
+ }
+
+
+ DEBUG(dbgs() << "SLP: Total Cost " << Cost + ExtractCost<< ".\n");
+ return Cost + ExtractCost;
+}
+
+int BoUpSLP::getGatherCost(Type *Ty) {
+ int Cost = 0;
+ for (unsigned i = 0, e = cast<VectorType>(Ty)->getNumElements(); i < e; ++i)
+ Cost += TTI->getVectorInstrCost(Instruction::InsertElement, Ty, i);
+ return Cost;
+}
+
+int BoUpSLP::getGatherCost(ArrayRef<Value *> VL) {
+ // Find the type of the operands in VL.
+ Type *ScalarTy = VL[0]->getType();
+ if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
+ ScalarTy = SI->getValueOperand()->getType();
+ VectorType *VecTy = VectorType::get(ScalarTy, VL.size());
+ // Find the cost of inserting/extracting values from the vector.
+ return getGatherCost(VecTy);
+}
+
+AliasAnalysis::Location BoUpSLP::getLocation(Instruction *I) {
+ if (StoreInst *SI = dyn_cast<StoreInst>(I))
+ return AA->getLocation(SI);
+ if (LoadInst *LI = dyn_cast<LoadInst>(I))
+ return AA->getLocation(LI);
+ return AliasAnalysis::Location();
+}
+
+Value *BoUpSLP::getPointerOperand(Value *I) {
+ if (LoadInst *LI = dyn_cast<LoadInst>(I))
+ return LI->getPointerOperand();
+ if (StoreInst *SI = dyn_cast<StoreInst>(I))
+ return SI->getPointerOperand();
+ return 0;
+}
+
+unsigned BoUpSLP::getAddressSpaceOperand(Value *I) {
+ if (LoadInst *L = dyn_cast<LoadInst>(I))
+ return L->getPointerAddressSpace();
+ if (StoreInst *S = dyn_cast<StoreInst>(I))
+ return S->getPointerAddressSpace();
+ return -1;
+}
+
+bool BoUpSLP::isConsecutiveAccess(Value *A, Value *B) {
+ Value *PtrA = getPointerOperand(A);
+ Value *PtrB = getPointerOperand(B);
+ unsigned ASA = getAddressSpaceOperand(A);
+ unsigned ASB = getAddressSpaceOperand(B);
+
+ // Check that the address spaces match and that the pointers are valid.
+ if (!PtrA || !PtrB || (ASA != ASB))
+ return false;
+
+ // Make sure that A and B are different pointers of the same type.
+ if (PtrA == PtrB || PtrA->getType() != PtrB->getType())
+ return false;
+
+ unsigned PtrBitWidth = DL->getPointerSizeInBits(ASA);
+ Type *Ty = cast<PointerType>(PtrA->getType())->getElementType();
+ APInt Size(PtrBitWidth, DL->getTypeStoreSize(Ty));
+
+ APInt OffsetA(PtrBitWidth, 0), OffsetB(PtrBitWidth, 0);
+ PtrA = PtrA->stripAndAccumulateInBoundsConstantOffsets(*DL, OffsetA);
+ PtrB = PtrB->stripAndAccumulateInBoundsConstantOffsets(*DL, OffsetB);
+
+ APInt OffsetDelta = OffsetB - OffsetA;
+
+ // Check if they are based on the same pointer. That makes the offsets
+ // sufficient.
+ if (PtrA == PtrB)
+ return OffsetDelta == Size;
+
+ // Compute the necessary base pointer delta to have the necessary final delta
+ // equal to the size.
+ APInt BaseDelta = Size - OffsetDelta;
+
+ // Otherwise compute the distance with SCEV between the base pointers.
+ const SCEV *PtrSCEVA = SE->getSCEV(PtrA);
+ const SCEV *PtrSCEVB = SE->getSCEV(PtrB);
+ const SCEV *C = SE->getConstant(BaseDelta);
+ const SCEV *X = SE->getAddExpr(PtrSCEVA, C);
+ return X == PtrSCEVB;
+}
+
+Value *BoUpSLP::getSinkBarrier(Instruction *Src, Instruction *Dst) {
+ assert(Src->getParent() == Dst->getParent() && "Not the same BB");
+ BasicBlock::iterator I = Src, E = Dst;
+ /// Scan all of the instruction from SRC to DST and check if
+ /// the source may alias.
+ for (++I; I != E; ++I) {
+ // Ignore store instructions that are marked as 'ignore'.
+ if (MemBarrierIgnoreList.count(I))
+ continue;
+ if (Src->mayWriteToMemory()) /* Write */ {
+ if (!I->mayReadOrWriteMemory())
+ continue;
+ } else /* Read */ {
+ if (!I->mayWriteToMemory())
+ continue;
+ }
+ AliasAnalysis::Location A = getLocation(&*I);
+ AliasAnalysis::Location B = getLocation(Src);
+
+ if (!A.Ptr || !B.Ptr || AA->alias(A, B))
+ return I;
+ }
+ return 0;
+}
+
+int BoUpSLP::getLastIndex(ArrayRef<Value *> VL) {
+ BasicBlock *BB = cast<Instruction>(VL[0])->getParent();
+ assert(BB == getSameBlock(VL) && BlocksNumbers.count(BB) && "Invalid block");
+ BlockNumbering &BN = BlocksNumbers[BB];
+
+ int MaxIdx = BN.getIndex(BB->getFirstNonPHI());
+ for (unsigned i = 0, e = VL.size(); i < e; ++i)
+ MaxIdx = std::max(MaxIdx, BN.getIndex(cast<Instruction>(VL[i])));
+ return MaxIdx;
+}
+
+Instruction *BoUpSLP::getLastInstruction(ArrayRef<Value *> VL) {
+ BasicBlock *BB = cast<Instruction>(VL[0])->getParent();
+ assert(BB == getSameBlock(VL) && BlocksNumbers.count(BB) && "Invalid block");
+ BlockNumbering &BN = BlocksNumbers[BB];
+
+ int MaxIdx = BN.getIndex(cast<Instruction>(VL[0]));
+ for (unsigned i = 1, e = VL.size(); i < e; ++i)
+ MaxIdx = std::max(MaxIdx, BN.getIndex(cast<Instruction>(VL[i])));
+ Instruction *I = BN.getInstruction(MaxIdx);
+ assert(I && "bad location");
+ return I;
+}
+
+void BoUpSLP::setInsertPointAfterBundle(ArrayRef<Value *> VL) {
+ Instruction *VL0 = cast<Instruction>(VL[0]);
+ Instruction *LastInst = getLastInstruction(VL);
+ BasicBlock::iterator NextInst = LastInst;
+ ++NextInst;
+ Builder.SetInsertPoint(VL0->getParent(), NextInst);
+ Builder.SetCurrentDebugLocation(VL0->getDebugLoc());
+}
+
+Value *BoUpSLP::Gather(ArrayRef<Value *> VL, VectorType *Ty) {
+ Value *Vec = UndefValue::get(Ty);
+ // Generate the 'InsertElement' instruction.
+ for (unsigned i = 0; i < Ty->getNumElements(); ++i) {
+ Vec = Builder.CreateInsertElement(Vec, VL[i], Builder.getInt32(i));
+ if (Instruction *Insrt = dyn_cast<Instruction>(Vec)) {
+ GatherSeq.insert(Insrt);
+ CSEBlocks.insert(Insrt->getParent());
+
+ // Add to our 'need-to-extract' list.
+ if (ScalarToTreeEntry.count(VL[i])) {
+ int Idx = ScalarToTreeEntry[VL[i]];
+ TreeEntry *E = &VectorizableTree[Idx];
+ // Find which lane we need to extract.
+ int FoundLane = -1;
+ for (unsigned Lane = 0, LE = VL.size(); Lane != LE; ++Lane) {
+ // Is this the lane of the scalar that we are looking for ?
+ if (E->Scalars[Lane] == VL[i]) {
+ FoundLane = Lane;
+ break;
+ }
+ }
+ assert(FoundLane >= 0 && "Could not find the correct lane");
+ ExternalUses.push_back(ExternalUser(VL[i], Insrt, FoundLane));
+ }
+ }
+ }
+
+ return Vec;
+}
+
+Value *BoUpSLP::alreadyVectorized(ArrayRef<Value *> VL) const {
+ SmallDenseMap<Value*, int>::const_iterator Entry
+ = ScalarToTreeEntry.find(VL[0]);
+ if (Entry != ScalarToTreeEntry.end()) {
+ int Idx = Entry->second;
+ const TreeEntry *En = &VectorizableTree[Idx];
+ if (En->isSame(VL) && En->VectorizedValue)
+ return En->VectorizedValue;
+ }
+ return 0;
+}
+
+Value *BoUpSLP::vectorizeTree(ArrayRef<Value *> VL) {
+ if (ScalarToTreeEntry.count(VL[0])) {
+ int Idx = ScalarToTreeEntry[VL[0]];
+ TreeEntry *E = &VectorizableTree[Idx];
+ if (E->isSame(VL))
+ return vectorizeTree(E);
+ }
+
+ Type *ScalarTy = VL[0]->getType();
+ if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
+ ScalarTy = SI->getValueOperand()->getType();
+ VectorType *VecTy = VectorType::get(ScalarTy, VL.size());
+
+ return Gather(VL, VecTy);
+}
+
+Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
+ IRBuilder<>::InsertPointGuard Guard(Builder);
+
+ if (E->VectorizedValue) {
+ DEBUG(dbgs() << "SLP: Diamond merged for " << *E->Scalars[0] << ".\n");
+ return E->VectorizedValue;
+ }
+
+ Instruction *VL0 = cast<Instruction>(E->Scalars[0]);
+ Type *ScalarTy = VL0->getType();
+ if (StoreInst *SI = dyn_cast<StoreInst>(VL0))
+ ScalarTy = SI->getValueOperand()->getType();
+ VectorType *VecTy = VectorType::get(ScalarTy, E->Scalars.size());
+
+ if (E->NeedToGather) {
+ setInsertPointAfterBundle(E->Scalars);
+ return Gather(E->Scalars, VecTy);
+ }
+
+ unsigned Opcode = VL0->getOpcode();
+ assert(Opcode == getSameOpcode(E->Scalars) && "Invalid opcode");
+
+ switch (Opcode) {
+ case Instruction::PHI: {
+ PHINode *PH = dyn_cast<PHINode>(VL0);
+ Builder.SetInsertPoint(PH->getParent()->getFirstNonPHI());
+ Builder.SetCurrentDebugLocation(PH->getDebugLoc());
+ PHINode *NewPhi = Builder.CreatePHI(VecTy, PH->getNumIncomingValues());
+ E->VectorizedValue = NewPhi;
+
+ // PHINodes may have multiple entries from the same block. We want to
+ // visit every block once.
+ SmallSet<BasicBlock*, 4> VisitedBBs;
+
+ for (unsigned i = 0, e = PH->getNumIncomingValues(); i < e; ++i) {
+ ValueList Operands;
+ BasicBlock *IBB = PH->getIncomingBlock(i);
+
+ if (!VisitedBBs.insert(IBB)) {
+ NewPhi->addIncoming(NewPhi->getIncomingValueForBlock(IBB), IBB);
+ continue;
+ }
+
+ // Prepare the operand vector.
+ for (unsigned j = 0; j < E->Scalars.size(); ++j)
+ Operands.push_back(cast<PHINode>(E->Scalars[j])->
+ getIncomingValueForBlock(IBB));
+
+ Builder.SetInsertPoint(IBB->getTerminator());
+ Builder.SetCurrentDebugLocation(PH->getDebugLoc());
+ Value *Vec = vectorizeTree(Operands);
+ NewPhi->addIncoming(Vec, IBB);
+ }
+
+ assert(NewPhi->getNumIncomingValues() == PH->getNumIncomingValues() &&
+ "Invalid number of incoming values");
+ return NewPhi;
+ }
+
+ case Instruction::ExtractElement: {
+ if (CanReuseExtract(E->Scalars)) {
+ Value *V = VL0->getOperand(0);
+ E->VectorizedValue = V;
+ return V;
+ }
+ return Gather(E->Scalars, VecTy);
+ }
+ case Instruction::ZExt:
+ case Instruction::SExt:
+ case Instruction::FPToUI:
+ case Instruction::FPToSI:
+ case Instruction::FPExt:
+ case Instruction::PtrToInt:
+ case Instruction::IntToPtr:
+ case Instruction::SIToFP:
+ case Instruction::UIToFP:
+ case Instruction::Trunc:
+ case Instruction::FPTrunc:
+ case Instruction::BitCast: {
+ ValueList INVL;
+ for (int i = 0, e = E->Scalars.size(); i < e; ++i)
+ INVL.push_back(cast<Instruction>(E->Scalars[i])->getOperand(0));
+
+ setInsertPointAfterBundle(E->Scalars);
+
+ Value *InVec = vectorizeTree(INVL);
+
+ if (Value *V = alreadyVectorized(E->Scalars))
+ return V;
+
+ CastInst *CI = dyn_cast<CastInst>(VL0);
+ Value *V = Builder.CreateCast(CI->getOpcode(), InVec, VecTy);
+ E->VectorizedValue = V;
+ return V;
+ }
+ case Instruction::FCmp:
+ case Instruction::ICmp: {
+ ValueList LHSV, RHSV;
+ for (int i = 0, e = E->Scalars.size(); i < e; ++i) {
+ LHSV.push_back(cast<Instruction>(E->Scalars[i])->getOperand(0));
+ RHSV.push_back(cast<Instruction>(E->Scalars[i])->getOperand(1));
+ }
+
+ setInsertPointAfterBundle(E->Scalars);
+
+ Value *L = vectorizeTree(LHSV);
+ Value *R = vectorizeTree(RHSV);
+
+ if (Value *V = alreadyVectorized(E->Scalars))
+ return V;
+
+ CmpInst::Predicate P0 = dyn_cast<CmpInst>(VL0)->getPredicate();
+ Value *V;
+ if (Opcode == Instruction::FCmp)
+ V = Builder.CreateFCmp(P0, L, R);
+ else
+ V = Builder.CreateICmp(P0, L, R);
+
+ E->VectorizedValue = V;
+ return V;
+ }
+ case Instruction::Select: {
+ ValueList TrueVec, FalseVec, CondVec;
+ for (int i = 0, e = E->Scalars.size(); i < e; ++i) {
+ CondVec.push_back(cast<Instruction>(E->Scalars[i])->getOperand(0));
+ TrueVec.push_back(cast<Instruction>(E->Scalars[i])->getOperand(1));
+ FalseVec.push_back(cast<Instruction>(E->Scalars[i])->getOperand(2));
+ }
+
+ setInsertPointAfterBundle(E->Scalars);
+
+ Value *Cond = vectorizeTree(CondVec);
+ Value *True = vectorizeTree(TrueVec);
+ Value *False = vectorizeTree(FalseVec);
+
+ if (Value *V = alreadyVectorized(E->Scalars))
+ return V;
+
+ Value *V = Builder.CreateSelect(Cond, True, False);
+ E->VectorizedValue = V;
+ return V;
+ }
+ case Instruction::Add:
+ case Instruction::FAdd:
+ case Instruction::Sub:
+ case Instruction::FSub:
+ case Instruction::Mul:
+ case Instruction::FMul:
+ case Instruction::UDiv:
+ case Instruction::SDiv:
+ case Instruction::FDiv:
+ case Instruction::URem:
+ case Instruction::SRem:
+ case Instruction::FRem:
+ case Instruction::Shl:
+ case Instruction::LShr:
+ case Instruction::AShr:
+ case Instruction::And:
+ case Instruction::Or:
+ case Instruction::Xor: {
+ ValueList LHSVL, RHSVL;
+ if (isa<BinaryOperator>(VL0) && VL0->isCommutative())
+ reorderInputsAccordingToOpcode(E->Scalars, LHSVL, RHSVL);
+ else
+ for (int i = 0, e = E->Scalars.size(); i < e; ++i) {
+ LHSVL.push_back(cast<Instruction>(E->Scalars[i])->getOperand(0));
+ RHSVL.push_back(cast<Instruction>(E->Scalars[i])->getOperand(1));
+ }
+
+ setInsertPointAfterBundle(E->Scalars);
+
+ Value *LHS = vectorizeTree(LHSVL);
+ Value *RHS = vectorizeTree(RHSVL);
+
+ if (LHS == RHS && isa<Instruction>(LHS)) {
+ assert((VL0->getOperand(0) == VL0->getOperand(1)) && "Invalid order");
+ }
+
+ if (Value *V = alreadyVectorized(E->Scalars))
+ return V;
+
+ BinaryOperator *BinOp = cast<BinaryOperator>(VL0);
+ Value *V = Builder.CreateBinOp(BinOp->getOpcode(), LHS, RHS);
+ E->VectorizedValue = V;
+
+ if (Instruction *I = dyn_cast<Instruction>(V))
+ return propagateMetadata(I, E->Scalars);
+
+ return V;
+ }
+ case Instruction::Load: {
+ // Loads are inserted at the head of the tree because we don't want to
+ // sink them all the way down past store instructions.
+ setInsertPointAfterBundle(E->Scalars);
+
+ LoadInst *LI = cast<LoadInst>(VL0);
+ unsigned AS = LI->getPointerAddressSpace();
+
+ Value *VecPtr = Builder.CreateBitCast(LI->getPointerOperand(),
+ VecTy->getPointerTo(AS));
+ unsigned Alignment = LI->getAlignment();
+ LI = Builder.CreateLoad(VecPtr);
+ LI->setAlignment(Alignment);
+ E->VectorizedValue = LI;
+ return propagateMetadata(LI, E->Scalars);
+ }
+ case Instruction::Store: {
+ StoreInst *SI = cast<StoreInst>(VL0);
+ unsigned Alignment = SI->getAlignment();
+ unsigned AS = SI->getPointerAddressSpace();
+
+ ValueList ValueOp;
+ for (int i = 0, e = E->Scalars.size(); i < e; ++i)
+ ValueOp.push_back(cast<StoreInst>(E->Scalars[i])->getValueOperand());
+
+ setInsertPointAfterBundle(E->Scalars);
+
+ Value *VecValue = vectorizeTree(ValueOp);
+ Value *VecPtr = Builder.CreateBitCast(SI->getPointerOperand(),
+ VecTy->getPointerTo(AS));
+ StoreInst *S = Builder.CreateStore(VecValue, VecPtr);
+ S->setAlignment(Alignment);
+ E->VectorizedValue = S;
+ return propagateMetadata(S, E->Scalars);
+ }
+ default:
+ llvm_unreachable("unknown inst");
+ }
+ return 0;
+}
+
+Value *BoUpSLP::vectorizeTree() {
+ Builder.SetInsertPoint(F->getEntryBlock().begin());
+ vectorizeTree(&VectorizableTree[0]);
+
+ DEBUG(dbgs() << "SLP: Extracting " << ExternalUses.size() << " values .\n");
+
+ // Extract all of the elements with the external uses.
+ for (UserList::iterator it = ExternalUses.begin(), e = ExternalUses.end();
+ it != e; ++it) {
+ Value *Scalar = it->Scalar;
+ llvm::User *User = it->User;
+
+ // Skip users that we already RAUW. This happens when one instruction
+ // has multiple uses of the same value.
+ if (std::find(Scalar->use_begin(), Scalar->use_end(), User) ==
+ Scalar->use_end())
+ continue;
+ assert(ScalarToTreeEntry.count(Scalar) && "Invalid scalar");
+
+ int Idx = ScalarToTreeEntry[Scalar];
+ TreeEntry *E = &VectorizableTree[Idx];
+ assert(!E->NeedToGather && "Extracting from a gather list");
+
+ Value *Vec = E->VectorizedValue;
+ assert(Vec && "Can't find vectorizable value");
+
+ Value *Lane = Builder.getInt32(it->Lane);
+ // Generate extracts for out-of-tree users.
+ // Find the insertion point for the extractelement lane.
+ if (PHINode *PN = dyn_cast<PHINode>(Vec)) {
+ Builder.SetInsertPoint(PN->getParent()->getFirstInsertionPt());
+ Value *Ex = Builder.CreateExtractElement(Vec, Lane);
+ CSEBlocks.insert(PN->getParent());
+ User->replaceUsesOfWith(Scalar, Ex);
+ } else if (isa<Instruction>(Vec)){
+ if (PHINode *PH = dyn_cast<PHINode>(User)) {
+ for (int i = 0, e = PH->getNumIncomingValues(); i != e; ++i) {
+ if (PH->getIncomingValue(i) == Scalar) {
+ Builder.SetInsertPoint(PH->getIncomingBlock(i)->getTerminator());
+ Value *Ex = Builder.CreateExtractElement(Vec, Lane);
+ CSEBlocks.insert(PH->getIncomingBlock(i));
+ PH->setOperand(i, Ex);
+ }
+ }
+ } else {
+ Builder.SetInsertPoint(cast<Instruction>(User));
+ Value *Ex = Builder.CreateExtractElement(Vec, Lane);
+ CSEBlocks.insert(cast<Instruction>(User)->getParent());
+ User->replaceUsesOfWith(Scalar, Ex);
+ }
+ } else {
+ Builder.SetInsertPoint(F->getEntryBlock().begin());
+ Value *Ex = Builder.CreateExtractElement(Vec, Lane);
+ CSEBlocks.insert(&F->getEntryBlock());
+ User->replaceUsesOfWith(Scalar, Ex);
+ }
+
+ DEBUG(dbgs() << "SLP: Replaced:" << *User << ".\n");
+ }
+
+ // For each vectorized value:
+ for (int EIdx = 0, EE = VectorizableTree.size(); EIdx < EE; ++EIdx) {
+ TreeEntry *Entry = &VectorizableTree[EIdx];
+
+ // For each lane:
+ for (int Lane = 0, LE = Entry->Scalars.size(); Lane != LE; ++Lane) {
+ Value *Scalar = Entry->Scalars[Lane];
+
+ // No need to handle users of gathered values.
+ if (Entry->NeedToGather)
+ continue;
+
+ assert(Entry->VectorizedValue && "Can't find vectorizable value");
+
+ Type *Ty = Scalar->getType();
+ if (!Ty->isVoidTy()) {
+ for (Value::use_iterator User = Scalar->use_begin(),
+ UE = Scalar->use_end(); User != UE; ++User) {
+ DEBUG(dbgs() << "SLP: \tvalidating user:" << **User << ".\n");
+
+ assert((ScalarToTreeEntry.count(*User) ||
+ // It is legal to replace the reduction users by undef.
+ (RdxOps && RdxOps->count(*User))) &&
+ "Replacing out-of-tree value with undef");
+ }
+ Value *Undef = UndefValue::get(Ty);
+ Scalar->replaceAllUsesWith(Undef);
+ }
+ DEBUG(dbgs() << "SLP: \tErasing scalar:" << *Scalar << ".\n");
+ cast<Instruction>(Scalar)->eraseFromParent();
+ }
+ }
+
+ for (Function::iterator it = F->begin(), e = F->end(); it != e; ++it) {
+ BlocksNumbers[it].forget();
+ }
+ Builder.ClearInsertionPoint();
+
+ return VectorizableTree[0].VectorizedValue;
+}
+
+class DTCmp {
+ const DominatorTree *DT;
+
+public:
+ DTCmp(const DominatorTree *DT) : DT(DT) {}
+ bool operator()(const BasicBlock *A, const BasicBlock *B) const {
+ return DT->properlyDominates(A, B);
+ }
+};
+
+void BoUpSLP::optimizeGatherSequence() {
+ DEBUG(dbgs() << "SLP: Optimizing " << GatherSeq.size()
+ << " gather sequences instructions.\n");
+ // LICM InsertElementInst sequences.
+ for (SetVector<Instruction *>::iterator it = GatherSeq.begin(),
+ e = GatherSeq.end(); it != e; ++it) {
+ InsertElementInst *Insert = dyn_cast<InsertElementInst>(*it);
+
+ if (!Insert)
+ continue;
+
+ // Check if this block is inside a loop.
+ Loop *L = LI->getLoopFor(Insert->getParent());
+ if (!L)
+ continue;
+
+ // Check if it has a preheader.
+ BasicBlock *PreHeader = L->getLoopPreheader();
+ if (!PreHeader)
+ continue;
+
+ // If the vector or the element that we insert into it are
+ // instructions that are defined in this basic block then we can't
+ // hoist this instruction.
+ Instruction *CurrVec = dyn_cast<Instruction>(Insert->getOperand(0));
+ Instruction *NewElem = dyn_cast<Instruction>(Insert->getOperand(1));
+ if (CurrVec && L->contains(CurrVec))
+ continue;
+ if (NewElem && L->contains(NewElem))
+ continue;
+
+ // We can hoist this instruction. Move it to the pre-header.
+ Insert->moveBefore(PreHeader->getTerminator());
+ }
+
+ // Sort blocks by domination. This ensures we visit a block after all blocks
+ // dominating it are visited.
+ SmallVector<BasicBlock *, 8> CSEWorkList(CSEBlocks.begin(), CSEBlocks.end());
+ std::stable_sort(CSEWorkList.begin(), CSEWorkList.end(), DTCmp(DT));
+
+ // Perform O(N^2) search over the gather sequences and merge identical
+ // instructions. TODO: We can further optimize this scan if we split the
+ // instructions into different buckets based on the insert lane.
+ SmallVector<Instruction *, 16> Visited;
+ for (SmallVectorImpl<BasicBlock *>::iterator I = CSEWorkList.begin(),
+ E = CSEWorkList.end();
+ I != E; ++I) {
+ assert((I == CSEWorkList.begin() || !DT->dominates(*I, *llvm::prior(I))) &&
+ "Worklist not sorted properly!");
+ BasicBlock *BB = *I;
+ // For all instructions in blocks containing gather sequences:
+ for (BasicBlock::iterator it = BB->begin(), e = BB->end(); it != e;) {
+ Instruction *In = it++;
+ if (!isa<InsertElementInst>(In) && !isa<ExtractElementInst>(In))
+ continue;
+
+ // Check if we can replace this instruction with any of the
+ // visited instructions.
+ for (SmallVectorImpl<Instruction *>::iterator v = Visited.begin(),
+ ve = Visited.end();
+ v != ve; ++v) {
+ if (In->isIdenticalTo(*v) &&
+ DT->dominates((*v)->getParent(), In->getParent())) {
+ In->replaceAllUsesWith(*v);
+ In->eraseFromParent();
+ In = 0;
+ break;
+ }
+ }
+ if (In) {
+ assert(std::find(Visited.begin(), Visited.end(), In) == Visited.end());
+ Visited.push_back(In);
+ }
+ }
+ }
+ CSEBlocks.clear();
+ GatherSeq.clear();
+}
+
/// The SLPVectorizer Pass.
struct SLPVectorizer : public FunctionPass {
- typedef std::map<Value*, BoUpSLP::StoreList> StoreListMap;
+ typedef SmallVector<StoreInst *, 8> StoreList;
+ typedef MapVector<Value *, StoreList> StoreListMap;
/// Pass identification, replacement for typeid
static char ID;
@@ -61,6 +1764,7 @@ struct SLPVectorizer : public FunctionPass {
TargetTransformInfo *TTI;
AliasAnalysis *AA;
LoopInfo *LI;
+ DominatorTree *DT;
virtual bool runOnFunction(Function &F) {
SE = &getAnalysis<ScalarEvolution>();
@@ -68,41 +1772,50 @@ struct SLPVectorizer : public FunctionPass {
TTI = &getAnalysis<TargetTransformInfo>();
AA = &getAnalysis<AliasAnalysis>();
LI = &getAnalysis<LoopInfo>();
+ DT = &getAnalysis<DominatorTree>();
StoreRefs.clear();
bool Changed = false;
+ // If the target claims to have no vector registers don't attempt
+ // vectorization.
+ if (!TTI->getNumberOfRegisters(true))
+ return false;
+
// Must have DataLayout. We can't require it because some tests run w/o
// triple.
if (!DL)
return false;
- for (Function::iterator it = F.begin(), e = F.end(); it != e; ++it) {
- BasicBlock *BB = it;
- bool BBChanged = false;
+ // Don't vectorize when the attribute NoImplicitFloat is used.
+ if (F.hasFnAttribute(Attribute::NoImplicitFloat))
+ return false;
- // Use the bollom up slp vectorizer to construct chains that start with
- // he store instructions.
- BoUpSLP R(BB, SE, DL, TTI, AA, LI->getLoopFor(BB));
+ DEBUG(dbgs() << "SLP: Analyzing blocks in " << F.getName() << ".\n");
- // Vectorize trees that end at reductions.
- BBChanged |= vectorizeReductions(BB, R);
+ // Use the bollom up slp vectorizer to construct chains that start with
+ // he store instructions.
+ BoUpSLP R(&F, SE, DL, TTI, AA, LI, DT);
+
+ // Scan the blocks in the function in post order.
+ for (po_iterator<BasicBlock*> it = po_begin(&F.getEntryBlock()),
+ e = po_end(&F.getEntryBlock()); it != e; ++it) {
+ BasicBlock *BB = *it;
// Vectorize trees that end at stores.
if (unsigned count = collectStores(BB, R)) {
(void)count;
- DEBUG(dbgs()<<"SLP: Found " << count << " stores to vectorize.\n");
- BBChanged |= vectorizeStoreChains(R);
+ DEBUG(dbgs() << "SLP: Found " << count << " stores to vectorize.\n");
+ Changed |= vectorizeStoreChains(R);
}
- // Try to hoist some of the scalarization code to the preheader.
- if (BBChanged) hoistGatherSequence(LI, BB, R);
-
- Changed |= BBChanged;
+ // Vectorize trees that end at reductions.
+ Changed |= vectorizeChainsInBlock(BB, R);
}
if (Changed) {
- DEBUG(dbgs()<<"SLP: vectorized \""<<F.getName()<<"\"\n");
+ R.optimizeGatherSequence();
+ DEBUG(dbgs() << "SLP: vectorized \"" << F.getName() << "\"\n");
DEBUG(verifyFunction(F));
}
return Changed;
@@ -114,6 +1827,10 @@ struct SLPVectorizer : public FunctionPass {
AU.addRequired<AliasAnalysis>();
AU.addRequired<TargetTransformInfo>();
AU.addRequired<LoopInfo>();
+ AU.addRequired<DominatorTree>();
+ AU.addPreserved<LoopInfo>();
+ AU.addPreserved<DominatorTree>();
+ AU.setPreservesCFG();
}
private:
@@ -125,29 +1842,149 @@ private:
unsigned collectStores(BasicBlock *BB, BoUpSLP &R);
/// \brief Try to vectorize a chain that starts at two arithmetic instrs.
- bool tryToVectorizePair(Value *A, Value *B, BoUpSLP &R);
+ bool tryToVectorizePair(Value *A, Value *B, BoUpSLP &R);
/// \brief Try to vectorize a list of operands.
+ /// \returns true if a value was vectorized.
bool tryToVectorizeList(ArrayRef<Value *> VL, BoUpSLP &R);
/// \brief Try to vectorize a chain that may start at the operands of \V;
- bool tryToVectorize(BinaryOperator *V, BoUpSLP &R);
+ bool tryToVectorize(BinaryOperator *V, BoUpSLP &R);
/// \brief Vectorize the stores that were collected in StoreRefs.
bool vectorizeStoreChains(BoUpSLP &R);
- /// \brief Try to hoist gather sequences outside of the loop in cases where
- /// all of the sources are loop invariant.
- void hoistGatherSequence(LoopInfo *LI, BasicBlock *BB, BoUpSLP &R);
+ /// \brief Scan the basic block and look for patterns that are likely to start
+ /// a vectorization chain.
+ bool vectorizeChainsInBlock(BasicBlock *BB, BoUpSLP &R);
- /// \brief Scan the basic block and look for reductions that may start a
- /// vectorization chain.
- bool vectorizeReductions(BasicBlock *BB, BoUpSLP &R);
+ bool vectorizeStoreChain(ArrayRef<Value *> Chain, int CostThreshold,
+ BoUpSLP &R);
+ bool vectorizeStores(ArrayRef<StoreInst *> Stores, int costThreshold,
+ BoUpSLP &R);
private:
StoreListMap StoreRefs;
};
+/// \brief Check that the Values in the slice in VL array are still existant in
+/// the WeakVH array.
+/// Vectorization of part of the VL array may cause later values in the VL array
+/// to become invalid. We track when this has happened in the WeakVH array.
+static bool hasValueBeenRAUWed(ArrayRef<Value *> &VL,
+ SmallVectorImpl<WeakVH> &VH,
+ unsigned SliceBegin,
+ unsigned SliceSize) {
+ for (unsigned i = SliceBegin; i < SliceBegin + SliceSize; ++i)
+ if (VH[i] != VL[i])
+ return true;
+
+ return false;
+}
+
+bool SLPVectorizer::vectorizeStoreChain(ArrayRef<Value *> Chain,
+ int CostThreshold, BoUpSLP &R) {
+ unsigned ChainLen = Chain.size();
+ DEBUG(dbgs() << "SLP: Analyzing a store chain of length " << ChainLen
+ << "\n");
+ Type *StoreTy = cast<StoreInst>(Chain[0])->getValueOperand()->getType();
+ unsigned Sz = DL->getTypeSizeInBits(StoreTy);
+ unsigned VF = MinVecRegSize / Sz;
+
+ if (!isPowerOf2_32(Sz) || VF < 2)
+ return false;
+
+ // Keep track of values that were delete by vectorizing in the loop below.
+ SmallVector<WeakVH, 8> TrackValues(Chain.begin(), Chain.end());
+
+ bool Changed = false;
+ // Look for profitable vectorizable trees at all offsets, starting at zero.
+ for (unsigned i = 0, e = ChainLen; i < e; ++i) {
+ if (i + VF > e)
+ break;
+
+ // Check that a previous iteration of this loop did not delete the Value.
+ if (hasValueBeenRAUWed(Chain, TrackValues, i, VF))
+ continue;
+
+ DEBUG(dbgs() << "SLP: Analyzing " << VF << " stores at offset " << i
+ << "\n");
+ ArrayRef<Value *> Operands = Chain.slice(i, VF);
+
+ R.buildTree(Operands);
+
+ int Cost = R.getTreeCost();
+
+ DEBUG(dbgs() << "SLP: Found cost=" << Cost << " for VF=" << VF << "\n");
+ if (Cost < CostThreshold) {
+ DEBUG(dbgs() << "SLP: Decided to vectorize cost=" << Cost << "\n");
+ R.vectorizeTree();
+
+ // Move to the next bundle.
+ i += VF - 1;
+ Changed = true;
+ }
+ }
+
+ return Changed;
+}
+
+bool SLPVectorizer::vectorizeStores(ArrayRef<StoreInst *> Stores,
+ int costThreshold, BoUpSLP &R) {
+ SetVector<Value *> Heads, Tails;
+ SmallDenseMap<Value *, Value *> ConsecutiveChain;
+
+ // We may run into multiple chains that merge into a single chain. We mark the
+ // stores that we vectorized so that we don't visit the same store twice.
+ BoUpSLP::ValueSet VectorizedStores;
+ bool Changed = false;
+
+ // Do a quadratic search on all of the given stores and find
+ // all of the pairs of stores that follow each other.
+ for (unsigned i = 0, e = Stores.size(); i < e; ++i) {
+ for (unsigned j = 0; j < e; ++j) {
+ if (i == j)
+ continue;
+
+ if (R.isConsecutiveAccess(Stores[i], Stores[j])) {
+ Tails.insert(Stores[j]);
+ Heads.insert(Stores[i]);
+ ConsecutiveChain[Stores[i]] = Stores[j];
+ }
+ }
+ }
+
+ // For stores that start but don't end a link in the chain:
+ for (SetVector<Value *>::iterator it = Heads.begin(), e = Heads.end();
+ it != e; ++it) {
+ if (Tails.count(*it))
+ continue;
+
+ // We found a store instr that starts a chain. Now follow the chain and try
+ // to vectorize it.
+ BoUpSLP::ValueList Operands;
+ Value *I = *it;
+ // Collect the chain into a list.
+ while (Tails.count(I) || Heads.count(I)) {
+ if (VectorizedStores.count(I))
+ break;
+ Operands.push_back(I);
+ // Move to the next value in the chain.
+ I = ConsecutiveChain[I];
+ }
+
+ bool Vectorized = vectorizeStoreChain(Operands, costThreshold, R);
+
+ // Mark the vectorized stores so that we don't vectorize them again.
+ if (Vectorized)
+ VectorizedStores.insert(Operands.begin(), Operands.end());
+ Changed |= Vectorized;
+ }
+
+ return Changed;
+}
+
+
unsigned SLPVectorizer::collectStores(BasicBlock *BB, BoUpSLP &R) {
unsigned count = 0;
StoreRefs.clear();
@@ -156,15 +1993,17 @@ unsigned SLPVectorizer::collectStores(BasicBlock *BB, BoUpSLP &R) {
if (!SI)
continue;
+ // Don't touch volatile stores.
+ if (!SI->isSimple())
+ continue;
+
// Check that the pointer points to scalars.
Type *Ty = SI->getValueOperand()->getType();
if (Ty->isAggregateType() || Ty->isVectorTy())
return 0;
- // Find the base of the GEP.
- Value *Ptr = SI->getPointerOperand();
- if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Ptr))
- Ptr = GEP->getPointerOperand();
+ // Find the base pointer.
+ Value *Ptr = GetUnderlyingObject(SI->getPointerOperand(), DL);
// Save the store locations.
StoreRefs[Ptr].push_back(SI);
@@ -173,34 +2012,83 @@ unsigned SLPVectorizer::collectStores(BasicBlock *BB, BoUpSLP &R) {
return count;
}
-bool SLPVectorizer::tryToVectorizePair(Value *A, Value *B, BoUpSLP &R) {
- if (!A || !B) return false;
+bool SLPVectorizer::tryToVectorizePair(Value *A, Value *B, BoUpSLP &R) {
+ if (!A || !B)
+ return false;
Value *VL[] = { A, B };
return tryToVectorizeList(VL, R);
}
bool SLPVectorizer::tryToVectorizeList(ArrayRef<Value *> VL, BoUpSLP &R) {
- DEBUG(dbgs()<<"SLP: Vectorizing a list of length = " << VL.size() << ".\n");
+ if (VL.size() < 2)
+ return false;
+
+ DEBUG(dbgs() << "SLP: Vectorizing a list of length = " << VL.size() << ".\n");
+
+ // Check that all of the parts are scalar instructions of the same type.
+ Instruction *I0 = dyn_cast<Instruction>(VL[0]);
+ if (!I0)
+ return false;
+
+ unsigned Opcode0 = I0->getOpcode();
+
+ Type *Ty0 = I0->getType();
+ unsigned Sz = DL->getTypeSizeInBits(Ty0);
+ unsigned VF = MinVecRegSize / Sz;
- // Check that all of the parts are scalar.
for (int i = 0, e = VL.size(); i < e; ++i) {
Type *Ty = VL[i]->getType();
if (Ty->isAggregateType() || Ty->isVectorTy())
- return 0;
+ return false;
+ Instruction *Inst = dyn_cast<Instruction>(VL[i]);
+ if (!Inst || Inst->getOpcode() != Opcode0)
+ return false;
}
- int Cost = R.getTreeCost(VL);
- int ExtrCost = R.getScalarizationCost(VL);
- DEBUG(dbgs()<<"SLP: Cost of pair:" << Cost <<
- " Cost of extract:" << ExtrCost << ".\n");
- if ((Cost+ExtrCost) >= -SLPCostThreshold) return false;
- DEBUG(dbgs()<<"SLP: Vectorizing pair.\n");
- R.vectorizeArith(VL);
- return true;
+ bool Changed = false;
+
+ // Keep track of values that were delete by vectorizing in the loop below.
+ SmallVector<WeakVH, 8> TrackValues(VL.begin(), VL.end());
+
+ for (unsigned i = 0, e = VL.size(); i < e; ++i) {
+ unsigned OpsWidth = 0;
+
+ if (i + VF > e)
+ OpsWidth = e - i;
+ else
+ OpsWidth = VF;
+
+ if (!isPowerOf2_32(OpsWidth) || OpsWidth < 2)
+ break;
+
+ // Check that a previous iteration of this loop did not delete the Value.
+ if (hasValueBeenRAUWed(VL, TrackValues, i, OpsWidth))
+ continue;
+
+ DEBUG(dbgs() << "SLP: Analyzing " << OpsWidth << " operations "
+ << "\n");
+ ArrayRef<Value *> Ops = VL.slice(i, OpsWidth);
+
+ R.buildTree(Ops);
+ int Cost = R.getTreeCost();
+
+ if (Cost < -SLPCostThreshold) {
+ DEBUG(dbgs() << "SLP: Vectorizing pair at cost:" << Cost << ".\n");
+ R.vectorizeTree();
+
+ // Move to the next bundle.
+ i += VF - 1;
+ Changed = true;
+ }
+ }
+
+ return Changed;
}
-bool SLPVectorizer::tryToVectorize(BinaryOperator *V, BoUpSLP &R) {
- if (!V) return false;
+bool SLPVectorizer::tryToVectorize(BinaryOperator *V, BoUpSLP &R) {
+ if (!V)
+ return false;
+
// Try to vectorize V.
if (tryToVectorizePair(V->getOperand(0), V->getOperand(1), R))
return true;
@@ -237,38 +2125,502 @@ bool SLPVectorizer::tryToVectorize(BinaryOperator *V, BoUpSLP &R) {
return 0;
}
-bool SLPVectorizer::vectorizeReductions(BasicBlock *BB, BoUpSLP &R) {
+/// \brief Generate a shuffle mask to be used in a reduction tree.
+///
+/// \param VecLen The length of the vector to be reduced.
+/// \param NumEltsToRdx The number of elements that should be reduced in the
+/// vector.
+/// \param IsPairwise Whether the reduction is a pairwise or splitting
+/// reduction. A pairwise reduction will generate a mask of
+/// <0,2,...> or <1,3,..> while a splitting reduction will generate
+/// <2,3, undef,undef> for a vector of 4 and NumElts = 2.
+/// \param IsLeft True will generate a mask of even elements, odd otherwise.
+static Value *createRdxShuffleMask(unsigned VecLen, unsigned NumEltsToRdx,
+ bool IsPairwise, bool IsLeft,
+ IRBuilder<> &Builder) {
+ assert((IsPairwise || !IsLeft) && "Don't support a <0,1,undef,...> mask");
+
+ SmallVector<Constant *, 32> ShuffleMask(
+ VecLen, UndefValue::get(Builder.getInt32Ty()));
+
+ if (IsPairwise)
+ // Build a mask of 0, 2, ... (left) or 1, 3, ... (right).
+ for (unsigned i = 0; i != NumEltsToRdx; ++i)
+ ShuffleMask[i] = Builder.getInt32(2 * i + !IsLeft);
+ else
+ // Move the upper half of the vector to the lower half.
+ for (unsigned i = 0; i != NumEltsToRdx; ++i)
+ ShuffleMask[i] = Builder.getInt32(NumEltsToRdx + i);
+
+ return ConstantVector::get(ShuffleMask);
+}
+
+
+/// Model horizontal reductions.
+///
+/// A horizontal reduction is a tree of reduction operations (currently add and
+/// fadd) that has operations that can be put into a vector as its leaf.
+/// For example, this tree:
+///
+/// mul mul mul mul
+/// \ / \ /
+/// + +
+/// \ /
+/// +
+/// This tree has "mul" as its reduced values and "+" as its reduction
+/// operations. A reduction might be feeding into a store or a binary operation
+/// feeding a phi.
+/// ...
+/// \ /
+/// +
+/// |
+/// phi +=
+///
+/// Or:
+/// ...
+/// \ /
+/// +
+/// |
+/// *p =
+///
+class HorizontalReduction {
+ SmallPtrSet<Value *, 16> ReductionOps;
+ SmallVector<Value *, 32> ReducedVals;
+
+ BinaryOperator *ReductionRoot;
+ PHINode *ReductionPHI;
+
+ /// The opcode of the reduction.
+ unsigned ReductionOpcode;
+ /// The opcode of the values we perform a reduction on.
+ unsigned ReducedValueOpcode;
+ /// The width of one full horizontal reduction operation.
+ unsigned ReduxWidth;
+ /// Should we model this reduction as a pairwise reduction tree or a tree that
+ /// splits the vector in halves and adds those halves.
+ bool IsPairwiseReduction;
+
+public:
+ HorizontalReduction()
+ : ReductionRoot(0), ReductionPHI(0), ReductionOpcode(0),
+ ReducedValueOpcode(0), ReduxWidth(0), IsPairwiseReduction(false) {}
+
+ /// \brief Try to find a reduction tree.
+ bool matchAssociativeReduction(PHINode *Phi, BinaryOperator *B,
+ DataLayout *DL) {
+ assert((!Phi ||
+ std::find(Phi->op_begin(), Phi->op_end(), B) != Phi->op_end()) &&
+ "Thi phi needs to use the binary operator");
+
+ // We could have a initial reductions that is not an add.
+ // r *= v1 + v2 + v3 + v4
+ // In such a case start looking for a tree rooted in the first '+'.
+ if (Phi) {
+ if (B->getOperand(0) == Phi) {
+ Phi = 0;
+ B = dyn_cast<BinaryOperator>(B->getOperand(1));
+ } else if (B->getOperand(1) == Phi) {
+ Phi = 0;
+ B = dyn_cast<BinaryOperator>(B->getOperand(0));
+ }
+ }
+
+ if (!B)
+ return false;
+
+ Type *Ty = B->getType();
+ if (Ty->isVectorTy())
+ return false;
+
+ ReductionOpcode = B->getOpcode();
+ ReducedValueOpcode = 0;
+ ReduxWidth = MinVecRegSize / DL->getTypeSizeInBits(Ty);
+ ReductionRoot = B;
+ ReductionPHI = Phi;
+
+ if (ReduxWidth < 4)
+ return false;
+
+ // We currently only support adds.
+ if (ReductionOpcode != Instruction::Add &&
+ ReductionOpcode != Instruction::FAdd)
+ return false;
+
+ // Post order traverse the reduction tree starting at B. We only handle true
+ // trees containing only binary operators.
+ SmallVector<std::pair<BinaryOperator *, unsigned>, 32> Stack;
+ Stack.push_back(std::make_pair(B, 0));
+ while (!Stack.empty()) {
+ BinaryOperator *TreeN = Stack.back().first;
+ unsigned EdgeToVist = Stack.back().second++;
+ bool IsReducedValue = TreeN->getOpcode() != ReductionOpcode;
+
+ // Only handle trees in the current basic block.
+ if (TreeN->getParent() != B->getParent())
+ return false;
+
+ // Each tree node needs to have one user except for the ultimate
+ // reduction.
+ if (!TreeN->hasOneUse() && TreeN != B)
+ return false;
+
+ // Postorder vist.
+ if (EdgeToVist == 2 || IsReducedValue) {
+ if (IsReducedValue) {
+ // Make sure that the opcodes of the operations that we are going to
+ // reduce match.
+ if (!ReducedValueOpcode)
+ ReducedValueOpcode = TreeN->getOpcode();
+ else if (ReducedValueOpcode != TreeN->getOpcode())
+ return false;
+ ReducedVals.push_back(TreeN);
+ } else {
+ // We need to be able to reassociate the adds.
+ if (!TreeN->isAssociative())
+ return false;
+ ReductionOps.insert(TreeN);
+ }
+ // Retract.
+ Stack.pop_back();
+ continue;
+ }
+
+ // Visit left or right.
+ Value *NextV = TreeN->getOperand(EdgeToVist);
+ BinaryOperator *Next = dyn_cast<BinaryOperator>(NextV);
+ if (Next)
+ Stack.push_back(std::make_pair(Next, 0));
+ else if (NextV != Phi)
+ return false;
+ }
+ return true;
+ }
+
+ /// \brief Attempt to vectorize the tree found by
+ /// matchAssociativeReduction.
+ bool tryToReduce(BoUpSLP &V, TargetTransformInfo *TTI) {
+ if (ReducedVals.empty())
+ return false;
+
+ unsigned NumReducedVals = ReducedVals.size();
+ if (NumReducedVals < ReduxWidth)
+ return false;
+
+ Value *VectorizedTree = 0;
+ IRBuilder<> Builder(ReductionRoot);
+ FastMathFlags Unsafe;
+ Unsafe.setUnsafeAlgebra();
+ Builder.SetFastMathFlags(Unsafe);
+ unsigned i = 0;
+
+ for (; i < NumReducedVals - ReduxWidth + 1; i += ReduxWidth) {
+ ArrayRef<Value *> ValsToReduce(&ReducedVals[i], ReduxWidth);
+ V.buildTree(ValsToReduce, &ReductionOps);
+
+ // Estimate cost.
+ int Cost = V.getTreeCost() + getReductionCost(TTI, ReducedVals[i]);
+ if (Cost >= -SLPCostThreshold)
+ break;
+
+ DEBUG(dbgs() << "SLP: Vectorizing horizontal reduction at cost:" << Cost
+ << ". (HorRdx)\n");
+
+ // Vectorize a tree.
+ DebugLoc Loc = cast<Instruction>(ReducedVals[i])->getDebugLoc();
+ Value *VectorizedRoot = V.vectorizeTree();
+
+ // Emit a reduction.
+ Value *ReducedSubTree = emitReduction(VectorizedRoot, Builder);
+ if (VectorizedTree) {
+ Builder.SetCurrentDebugLocation(Loc);
+ VectorizedTree = createBinOp(Builder, ReductionOpcode, VectorizedTree,
+ ReducedSubTree, "bin.rdx");
+ } else
+ VectorizedTree = ReducedSubTree;
+ }
+
+ if (VectorizedTree) {
+ // Finish the reduction.
+ for (; i < NumReducedVals; ++i) {
+ Builder.SetCurrentDebugLocation(
+ cast<Instruction>(ReducedVals[i])->getDebugLoc());
+ VectorizedTree = createBinOp(Builder, ReductionOpcode, VectorizedTree,
+ ReducedVals[i]);
+ }
+ // Update users.
+ if (ReductionPHI) {
+ assert(ReductionRoot != NULL && "Need a reduction operation");
+ ReductionRoot->setOperand(0, VectorizedTree);
+ ReductionRoot->setOperand(1, ReductionPHI);
+ } else
+ ReductionRoot->replaceAllUsesWith(VectorizedTree);
+ }
+ return VectorizedTree != 0;
+ }
+
+private:
+
+ /// \brief Calcuate the cost of a reduction.
+ int getReductionCost(TargetTransformInfo *TTI, Value *FirstReducedVal) {
+ Type *ScalarTy = FirstReducedVal->getType();
+ Type *VecTy = VectorType::get(ScalarTy, ReduxWidth);
+
+ int PairwiseRdxCost = TTI->getReductionCost(ReductionOpcode, VecTy, true);
+ int SplittingRdxCost = TTI->getReductionCost(ReductionOpcode, VecTy, false);
+
+ IsPairwiseReduction = PairwiseRdxCost < SplittingRdxCost;
+ int VecReduxCost = IsPairwiseReduction ? PairwiseRdxCost : SplittingRdxCost;
+
+ int ScalarReduxCost =
+ ReduxWidth * TTI->getArithmeticInstrCost(ReductionOpcode, VecTy);
+
+ DEBUG(dbgs() << "SLP: Adding cost " << VecReduxCost - ScalarReduxCost
+ << " for reduction that starts with " << *FirstReducedVal
+ << " (It is a "
+ << (IsPairwiseReduction ? "pairwise" : "splitting")
+ << " reduction)\n");
+
+ return VecReduxCost - ScalarReduxCost;
+ }
+
+ static Value *createBinOp(IRBuilder<> &Builder, unsigned Opcode, Value *L,
+ Value *R, const Twine &Name = "") {
+ if (Opcode == Instruction::FAdd)
+ return Builder.CreateFAdd(L, R, Name);
+ return Builder.CreateBinOp((Instruction::BinaryOps)Opcode, L, R, Name);
+ }
+
+ /// \brief Emit a horizontal reduction of the vectorized value.
+ Value *emitReduction(Value *VectorizedValue, IRBuilder<> &Builder) {
+ assert(VectorizedValue && "Need to have a vectorized tree node");
+ Instruction *ValToReduce = dyn_cast<Instruction>(VectorizedValue);
+ assert(isPowerOf2_32(ReduxWidth) &&
+ "We only handle power-of-two reductions for now");
+
+ Value *TmpVec = ValToReduce;
+ for (unsigned i = ReduxWidth / 2; i != 0; i >>= 1) {
+ if (IsPairwiseReduction) {
+ Value *LeftMask =
+ createRdxShuffleMask(ReduxWidth, i, true, true, Builder);
+ Value *RightMask =
+ createRdxShuffleMask(ReduxWidth, i, true, false, Builder);
+
+ Value *LeftShuf = Builder.CreateShuffleVector(
+ TmpVec, UndefValue::get(TmpVec->getType()), LeftMask, "rdx.shuf.l");
+ Value *RightShuf = Builder.CreateShuffleVector(
+ TmpVec, UndefValue::get(TmpVec->getType()), (RightMask),
+ "rdx.shuf.r");
+ TmpVec = createBinOp(Builder, ReductionOpcode, LeftShuf, RightShuf,
+ "bin.rdx");
+ } else {
+ Value *UpperHalf =
+ createRdxShuffleMask(ReduxWidth, i, false, false, Builder);
+ Value *Shuf = Builder.CreateShuffleVector(
+ TmpVec, UndefValue::get(TmpVec->getType()), UpperHalf, "rdx.shuf");
+ TmpVec = createBinOp(Builder, ReductionOpcode, TmpVec, Shuf, "bin.rdx");
+ }
+ }
+
+ // The result is in the first element of the vector.
+ return Builder.CreateExtractElement(TmpVec, Builder.getInt32(0));
+ }
+};
+
+/// \brief Recognize construction of vectors like
+/// %ra = insertelement <4 x float> undef, float %s0, i32 0
+/// %rb = insertelement <4 x float> %ra, float %s1, i32 1
+/// %rc = insertelement <4 x float> %rb, float %s2, i32 2
+/// %rd = insertelement <4 x float> %rc, float %s3, i32 3
+///
+/// Returns true if it matches
+///
+static bool findBuildVector(InsertElementInst *IE,
+ SmallVectorImpl<Value *> &Ops) {
+ if (!isa<UndefValue>(IE->getOperand(0)))
+ return false;
+
+ while (true) {
+ Ops.push_back(IE->getOperand(1));
+
+ if (IE->use_empty())
+ return false;
+
+ InsertElementInst *NextUse = dyn_cast<InsertElementInst>(IE->use_back());
+ if (!NextUse)
+ return true;
+
+ // If this isn't the final use, make sure the next insertelement is the only
+ // use. It's OK if the final constructed vector is used multiple times
+ if (!IE->hasOneUse())
+ return false;
+
+ IE = NextUse;
+ }
+
+ return false;
+}
+
+static bool PhiTypeSorterFunc(Value *V, Value *V2) {
+ return V->getType() < V2->getType();
+}
+
+bool SLPVectorizer::vectorizeChainsInBlock(BasicBlock *BB, BoUpSLP &R) {
bool Changed = false;
- for (BasicBlock::iterator it = BB->begin(), e = BB->end(); it != e; ++it) {
- if (isa<DbgInfoIntrinsic>(it)) continue;
+ SmallVector<Value *, 4> Incoming;
+ SmallSet<Value *, 16> VisitedInstrs;
+
+ bool HaveVectorizedPhiNodes = true;
+ while (HaveVectorizedPhiNodes) {
+ HaveVectorizedPhiNodes = false;
+
+ // Collect the incoming values from the PHIs.
+ Incoming.clear();
+ for (BasicBlock::iterator instr = BB->begin(), ie = BB->end(); instr != ie;
+ ++instr) {
+ PHINode *P = dyn_cast<PHINode>(instr);
+ if (!P)
+ break;
+
+ if (!VisitedInstrs.count(P))
+ Incoming.push_back(P);
+ }
+
+ // Sort by type.
+ std::stable_sort(Incoming.begin(), Incoming.end(), PhiTypeSorterFunc);
+
+ // Try to vectorize elements base on their type.
+ for (SmallVector<Value *, 4>::iterator IncIt = Incoming.begin(),
+ E = Incoming.end();
+ IncIt != E;) {
+
+ // Look for the next elements with the same type.
+ SmallVector<Value *, 4>::iterator SameTypeIt = IncIt;
+ while (SameTypeIt != E &&
+ (*SameTypeIt)->getType() == (*IncIt)->getType()) {
+ VisitedInstrs.insert(*SameTypeIt);
+ ++SameTypeIt;
+ }
+
+ // Try to vectorize them.
+ unsigned NumElts = (SameTypeIt - IncIt);
+ DEBUG(errs() << "SLP: Trying to vectorize starting at PHIs (" << NumElts << ")\n");
+ if (NumElts > 1 &&
+ tryToVectorizeList(ArrayRef<Value *>(IncIt, NumElts), R)) {
+ // Success start over because instructions might have been changed.
+ HaveVectorizedPhiNodes = true;
+ Changed = true;
+ break;
+ }
+
+ // Start over at the next instruction of a differnt type (or the end).
+ IncIt = SameTypeIt;
+ }
+ }
+
+ VisitedInstrs.clear();
+
+ for (BasicBlock::iterator it = BB->begin(), e = BB->end(); it != e; it++) {
+ // We may go through BB multiple times so skip the one we have checked.
+ if (!VisitedInstrs.insert(it))
+ continue;
+
+ if (isa<DbgInfoIntrinsic>(it))
+ continue;
// Try to vectorize reductions that use PHINodes.
if (PHINode *P = dyn_cast<PHINode>(it)) {
// Check that the PHI is a reduction PHI.
- if (P->getNumIncomingValues() != 2) return Changed;
- Value *Rdx = (P->getIncomingBlock(0) == BB ? P->getIncomingValue(0) :
- (P->getIncomingBlock(1) == BB ? P->getIncomingValue(1) :
- 0));
+ if (P->getNumIncomingValues() != 2)
+ return Changed;
+ Value *Rdx =
+ (P->getIncomingBlock(0) == BB
+ ? (P->getIncomingValue(0))
+ : (P->getIncomingBlock(1) == BB ? P->getIncomingValue(1) : 0));
// Check if this is a Binary Operator.
BinaryOperator *BI = dyn_cast_or_null<BinaryOperator>(Rdx);
if (!BI)
continue;
- Value *Inst = BI->getOperand(0);
- if (Inst == P) Inst = BI->getOperand(1);
- Changed |= tryToVectorize(dyn_cast<BinaryOperator>(Inst), R);
+ // Try to match and vectorize a horizontal reduction.
+ HorizontalReduction HorRdx;
+ if (ShouldVectorizeHor &&
+ HorRdx.matchAssociativeReduction(P, BI, DL) &&
+ HorRdx.tryToReduce(R, TTI)) {
+ Changed = true;
+ it = BB->begin();
+ e = BB->end();
+ continue;
+ }
+
+ Value *Inst = BI->getOperand(0);
+ if (Inst == P)
+ Inst = BI->getOperand(1);
+
+ if (tryToVectorize(dyn_cast<BinaryOperator>(Inst), R)) {
+ // We would like to start over since some instructions are deleted
+ // and the iterator may become invalid value.
+ Changed = true;
+ it = BB->begin();
+ e = BB->end();
+ continue;
+ }
+
continue;
}
+ // Try to vectorize horizontal reductions feeding into a store.
+ if (ShouldStartVectorizeHorAtStore)
+ if (StoreInst *SI = dyn_cast<StoreInst>(it))
+ if (BinaryOperator *BinOp =
+ dyn_cast<BinaryOperator>(SI->getValueOperand())) {
+ HorizontalReduction HorRdx;
+ if (((HorRdx.matchAssociativeReduction(0, BinOp, DL) &&
+ HorRdx.tryToReduce(R, TTI)) ||
+ tryToVectorize(BinOp, R))) {
+ Changed = true;
+ it = BB->begin();
+ e = BB->end();
+ continue;
+ }
+ }
+
// Try to vectorize trees that start at compare instructions.
if (CmpInst *CI = dyn_cast<CmpInst>(it)) {
if (tryToVectorizePair(CI->getOperand(0), CI->getOperand(1), R)) {
- Changed |= true;
+ Changed = true;
+ // We would like to start over since some instructions are deleted
+ // and the iterator may become invalid value.
+ it = BB->begin();
+ e = BB->end();
continue;
}
- for (int i = 0; i < 2; ++i)
- if (BinaryOperator *BI = dyn_cast<BinaryOperator>(CI->getOperand(i)))
- Changed |= tryToVectorizePair(BI->getOperand(0), BI->getOperand(1), R);
+
+ for (int i = 0; i < 2; ++i) {
+ if (BinaryOperator *BI = dyn_cast<BinaryOperator>(CI->getOperand(i))) {
+ if (tryToVectorizePair(BI->getOperand(0), BI->getOperand(1), R)) {
+ Changed = true;
+ // We would like to start over since some instructions are deleted
+ // and the iterator may become invalid value.
+ it = BB->begin();
+ e = BB->end();
+ }
+ }
+ }
+ continue;
+ }
+
+ // Try to vectorize trees that start at insertelement instructions.
+ if (InsertElementInst *IE = dyn_cast<InsertElementInst>(it)) {
+ SmallVector<Value *, 8> Ops;
+ if (!findBuildVector(IE, Ops))
+ continue;
+
+ if (tryToVectorizeList(Ops, R)) {
+ Changed = true;
+ it = BB->begin();
+ e = BB->end();
+ }
+
continue;
}
}
@@ -284,51 +2636,19 @@ bool SLPVectorizer::vectorizeStoreChains(BoUpSLP &R) {
if (it->second.size() < 2)
continue;
- DEBUG(dbgs()<<"SLP: Analyzing a store chain of length " <<
- it->second.size() << ".\n");
+ DEBUG(dbgs() << "SLP: Analyzing a store chain of length "
+ << it->second.size() << ".\n");
- Changed |= R.vectorizeStores(it->second, -SLPCostThreshold);
+ // Process the stores in chunks of 16.
+ for (unsigned CI = 0, CE = it->second.size(); CI < CE; CI+=16) {
+ unsigned Len = std::min<unsigned>(CE - CI, 16);
+ ArrayRef<StoreInst *> Chunk(&it->second[CI], Len);
+ Changed |= vectorizeStores(Chunk, -SLPCostThreshold, R);
+ }
}
return Changed;
}
-void SLPVectorizer::hoistGatherSequence(LoopInfo *LI, BasicBlock *BB,
- BoUpSLP &R) {
- // Check if this block is inside a loop.
- Loop *L = LI->getLoopFor(BB);
- if (!L)
- return;
-
- // Check if it has a preheader.
- BasicBlock *PreHeader = L->getLoopPreheader();
- if (!PreHeader)
- return;
-
- // Mark the insertion point for the block.
- Instruction *Location = PreHeader->getTerminator();
-
- BoUpSLP::ValueList &Gathers = R.getGatherSeqInstructions();
- for (BoUpSLP::ValueList::iterator it = Gathers.begin(), e = Gathers.end();
- it != e; ++it) {
- InsertElementInst *Insert = dyn_cast<InsertElementInst>(*it);
-
- // The InsertElement sequence can be simplified into a constant.
- if (!Insert)
- continue;
-
- // If the vector or the element that we insert into it are
- // instructions that are defined in this basic block then we can't
- // hoist this instruction.
- Instruction *CurrVec = dyn_cast<Instruction>(Insert->getOperand(0));
- Instruction *NewElem = dyn_cast<Instruction>(Insert->getOperand(1));
- if (CurrVec && L->contains(CurrVec)) continue;
- if (NewElem && L->contains(NewElem)) continue;
-
- // We can hoist this instruction. Move it to the pre-header.
- Insert->moveBefore(Location);
- }
-}
-
} // end anonymous namespace
char SLPVectorizer::ID = 0;
@@ -341,8 +2661,5 @@ INITIALIZE_PASS_DEPENDENCY(LoopSimplify)
INITIALIZE_PASS_END(SLPVectorizer, SV_NAME, lv_name, false, false)
namespace llvm {
- Pass *createSLPVectorizerPass() {
- return new SLPVectorizer();
- }
+Pass *createSLPVectorizerPass() { return new SLPVectorizer(); }
}
-
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