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|
//===- VPlan.cpp - Vectorizer Plan ----------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
///
/// \file
/// This is the LLVM vectorization plan. It represents a candidate for
/// vectorization, allowing to plan and optimize how to vectorize a given loop
/// before generating LLVM-IR.
/// The vectorizer uses vectorization plans to estimate the costs of potential
/// candidates and if profitable to execute the desired plan, generating vector
/// LLVM-IR code.
///
//===----------------------------------------------------------------------===//
#include "VPlan.h"
#include "VPlanCFG.h"
#include "VPlanDominatorTree.h"
#include "VPlanPatternMatch.h"
#include "llvm/ADT/PostOrderIterator.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/Twine.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/Value.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/GenericDomTreeConstruction.h"
#include "llvm/Support/GraphWriter.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/LoopVersioning.h"
#include "llvm/Transforms/Utils/ScalarEvolutionExpander.h"
#include <cassert>
#include <string>
#include <vector>
using namespace llvm;
using namespace llvm::VPlanPatternMatch;
namespace llvm {
extern cl::opt<bool> EnableVPlanNativePath;
}
#define DEBUG_TYPE "vplan"
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
raw_ostream &llvm::operator<<(raw_ostream &OS, const VPValue &V) {
const VPInstruction *Instr = dyn_cast<VPInstruction>(&V);
VPSlotTracker SlotTracker(
(Instr && Instr->getParent()) ? Instr->getParent()->getPlan() : nullptr);
V.print(OS, SlotTracker);
return OS;
}
#endif
Value *VPLane::getAsRuntimeExpr(IRBuilderBase &Builder,
const ElementCount &VF) const {
switch (LaneKind) {
case VPLane::Kind::ScalableLast:
// Lane = RuntimeVF - VF.getKnownMinValue() + Lane
return Builder.CreateSub(getRuntimeVF(Builder, Builder.getInt32Ty(), VF),
Builder.getInt32(VF.getKnownMinValue() - Lane));
case VPLane::Kind::First:
return Builder.getInt32(Lane);
}
llvm_unreachable("Unknown lane kind");
}
VPValue::VPValue(const unsigned char SC, Value *UV, VPDef *Def)
: SubclassID(SC), UnderlyingVal(UV), Def(Def) {
if (Def)
Def->addDefinedValue(this);
}
VPValue::~VPValue() {
assert(Users.empty() && "trying to delete a VPValue with remaining users");
if (Def)
Def->removeDefinedValue(this);
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void VPValue::print(raw_ostream &OS, VPSlotTracker &SlotTracker) const {
if (const VPRecipeBase *R = dyn_cast_or_null<VPRecipeBase>(Def))
R->print(OS, "", SlotTracker);
else
printAsOperand(OS, SlotTracker);
}
void VPValue::dump() const {
const VPRecipeBase *Instr = dyn_cast_or_null<VPRecipeBase>(this->Def);
VPSlotTracker SlotTracker(
(Instr && Instr->getParent()) ? Instr->getParent()->getPlan() : nullptr);
print(dbgs(), SlotTracker);
dbgs() << "\n";
}
void VPDef::dump() const {
const VPRecipeBase *Instr = dyn_cast_or_null<VPRecipeBase>(this);
VPSlotTracker SlotTracker(
(Instr && Instr->getParent()) ? Instr->getParent()->getPlan() : nullptr);
print(dbgs(), "", SlotTracker);
dbgs() << "\n";
}
#endif
VPRecipeBase *VPValue::getDefiningRecipe() {
return cast_or_null<VPRecipeBase>(Def);
}
const VPRecipeBase *VPValue::getDefiningRecipe() const {
return cast_or_null<VPRecipeBase>(Def);
}
// Get the top-most entry block of \p Start. This is the entry block of the
// containing VPlan. This function is templated to support both const and non-const blocks
template <typename T> static T *getPlanEntry(T *Start) {
T *Next = Start;
T *Current = Start;
while ((Next = Next->getParent()))
Current = Next;
SmallSetVector<T *, 8> WorkList;
WorkList.insert(Current);
for (unsigned i = 0; i < WorkList.size(); i++) {
T *Current = WorkList[i];
if (Current->getNumPredecessors() == 0)
return Current;
auto &Predecessors = Current->getPredecessors();
WorkList.insert(Predecessors.begin(), Predecessors.end());
}
llvm_unreachable("VPlan without any entry node without predecessors");
}
VPlan *VPBlockBase::getPlan() { return getPlanEntry(this)->Plan; }
const VPlan *VPBlockBase::getPlan() const { return getPlanEntry(this)->Plan; }
/// \return the VPBasicBlock that is the entry of Block, possibly indirectly.
const VPBasicBlock *VPBlockBase::getEntryBasicBlock() const {
const VPBlockBase *Block = this;
while (const VPRegionBlock *Region = dyn_cast<VPRegionBlock>(Block))
Block = Region->getEntry();
return cast<VPBasicBlock>(Block);
}
VPBasicBlock *VPBlockBase::getEntryBasicBlock() {
VPBlockBase *Block = this;
while (VPRegionBlock *Region = dyn_cast<VPRegionBlock>(Block))
Block = Region->getEntry();
return cast<VPBasicBlock>(Block);
}
void VPBlockBase::setPlan(VPlan *ParentPlan) {
assert(
(ParentPlan->getEntry() == this || ParentPlan->getPreheader() == this) &&
"Can only set plan on its entry or preheader block.");
Plan = ParentPlan;
}
/// \return the VPBasicBlock that is the exit of Block, possibly indirectly.
const VPBasicBlock *VPBlockBase::getExitingBasicBlock() const {
const VPBlockBase *Block = this;
while (const VPRegionBlock *Region = dyn_cast<VPRegionBlock>(Block))
Block = Region->getExiting();
return cast<VPBasicBlock>(Block);
}
VPBasicBlock *VPBlockBase::getExitingBasicBlock() {
VPBlockBase *Block = this;
while (VPRegionBlock *Region = dyn_cast<VPRegionBlock>(Block))
Block = Region->getExiting();
return cast<VPBasicBlock>(Block);
}
VPBlockBase *VPBlockBase::getEnclosingBlockWithSuccessors() {
if (!Successors.empty() || !Parent)
return this;
assert(Parent->getExiting() == this &&
"Block w/o successors not the exiting block of its parent.");
return Parent->getEnclosingBlockWithSuccessors();
}
VPBlockBase *VPBlockBase::getEnclosingBlockWithPredecessors() {
if (!Predecessors.empty() || !Parent)
return this;
assert(Parent->getEntry() == this &&
"Block w/o predecessors not the entry of its parent.");
return Parent->getEnclosingBlockWithPredecessors();
}
void VPBlockBase::deleteCFG(VPBlockBase *Entry) {
for (VPBlockBase *Block : to_vector(vp_depth_first_shallow(Entry)))
delete Block;
}
VPBasicBlock::iterator VPBasicBlock::getFirstNonPhi() {
iterator It = begin();
while (It != end() && It->isPhi())
It++;
return It;
}
VPTransformState::VPTransformState(ElementCount VF, unsigned UF, LoopInfo *LI,
DominatorTree *DT, IRBuilderBase &Builder,
InnerLoopVectorizer *ILV, VPlan *Plan,
LLVMContext &Ctx)
: VF(VF), UF(UF), LI(LI), DT(DT), Builder(Builder), ILV(ILV), Plan(Plan),
LVer(nullptr),
TypeAnalysis(Plan->getCanonicalIV()->getScalarType(), Ctx) {}
Value *VPTransformState::get(VPValue *Def, const VPIteration &Instance) {
if (Def->isLiveIn())
return Def->getLiveInIRValue();
if (hasScalarValue(Def, Instance)) {
return Data
.PerPartScalars[Def][Instance.Part][Instance.Lane.mapToCacheIndex(VF)];
}
assert(hasVectorValue(Def, Instance.Part));
auto *VecPart = Data.PerPartOutput[Def][Instance.Part];
if (!VecPart->getType()->isVectorTy()) {
assert(Instance.Lane.isFirstLane() && "cannot get lane > 0 for scalar");
return VecPart;
}
// TODO: Cache created scalar values.
Value *Lane = Instance.Lane.getAsRuntimeExpr(Builder, VF);
auto *Extract = Builder.CreateExtractElement(VecPart, Lane);
// set(Def, Extract, Instance);
return Extract;
}
Value *VPTransformState::get(VPValue *Def, unsigned Part, bool NeedsScalar) {
if (NeedsScalar) {
assert((VF.isScalar() || Def->isLiveIn() ||
(hasScalarValue(Def, VPIteration(Part, 0)) &&
Data.PerPartScalars[Def][Part].size() == 1)) &&
"Trying to access a single scalar per part but has multiple scalars "
"per part.");
return get(Def, VPIteration(Part, 0));
}
// If Values have been set for this Def return the one relevant for \p Part.
if (hasVectorValue(Def, Part))
return Data.PerPartOutput[Def][Part];
auto GetBroadcastInstrs = [this, Def](Value *V) {
bool SafeToHoist = Def->isDefinedOutsideVectorRegions();
if (VF.isScalar())
return V;
// Place the code for broadcasting invariant variables in the new preheader.
IRBuilder<>::InsertPointGuard Guard(Builder);
if (SafeToHoist) {
BasicBlock *LoopVectorPreHeader = CFG.VPBB2IRBB[cast<VPBasicBlock>(
Plan->getVectorLoopRegion()->getSinglePredecessor())];
if (LoopVectorPreHeader)
Builder.SetInsertPoint(LoopVectorPreHeader->getTerminator());
}
// Place the code for broadcasting invariant variables in the new preheader.
// Broadcast the scalar into all locations in the vector.
Value *Shuf = Builder.CreateVectorSplat(VF, V, "broadcast");
return Shuf;
};
if (!hasScalarValue(Def, {Part, 0})) {
assert(Def->isLiveIn() && "expected a live-in");
if (Part != 0)
return get(Def, 0);
Value *IRV = Def->getLiveInIRValue();
Value *B = GetBroadcastInstrs(IRV);
set(Def, B, Part);
return B;
}
Value *ScalarValue = get(Def, {Part, 0});
// If we aren't vectorizing, we can just copy the scalar map values over
// to the vector map.
if (VF.isScalar()) {
set(Def, ScalarValue, Part);
return ScalarValue;
}
bool IsUniform = vputils::isUniformAfterVectorization(Def);
unsigned LastLane = IsUniform ? 0 : VF.getKnownMinValue() - 1;
// Check if there is a scalar value for the selected lane.
if (!hasScalarValue(Def, {Part, LastLane})) {
// At the moment, VPWidenIntOrFpInductionRecipes, VPScalarIVStepsRecipes and
// VPExpandSCEVRecipes can also be uniform.
assert((isa<VPWidenIntOrFpInductionRecipe>(Def->getDefiningRecipe()) ||
isa<VPScalarIVStepsRecipe>(Def->getDefiningRecipe()) ||
isa<VPExpandSCEVRecipe>(Def->getDefiningRecipe())) &&
"unexpected recipe found to be invariant");
IsUniform = true;
LastLane = 0;
}
auto *LastInst = cast<Instruction>(get(Def, {Part, LastLane}));
// Set the insert point after the last scalarized instruction or after the
// last PHI, if LastInst is a PHI. This ensures the insertelement sequence
// will directly follow the scalar definitions.
auto OldIP = Builder.saveIP();
auto NewIP =
isa<PHINode>(LastInst)
? BasicBlock::iterator(LastInst->getParent()->getFirstNonPHI())
: std::next(BasicBlock::iterator(LastInst));
Builder.SetInsertPoint(&*NewIP);
// However, if we are vectorizing, we need to construct the vector values.
// If the value is known to be uniform after vectorization, we can just
// broadcast the scalar value corresponding to lane zero for each unroll
// iteration. Otherwise, we construct the vector values using
// insertelement instructions. Since the resulting vectors are stored in
// State, we will only generate the insertelements once.
Value *VectorValue = nullptr;
if (IsUniform) {
VectorValue = GetBroadcastInstrs(ScalarValue);
set(Def, VectorValue, Part);
} else {
// Initialize packing with insertelements to start from undef.
assert(!VF.isScalable() && "VF is assumed to be non scalable.");
Value *Undef = PoisonValue::get(VectorType::get(LastInst->getType(), VF));
set(Def, Undef, Part);
for (unsigned Lane = 0; Lane < VF.getKnownMinValue(); ++Lane)
packScalarIntoVectorValue(Def, {Part, Lane});
VectorValue = get(Def, Part);
}
Builder.restoreIP(OldIP);
return VectorValue;
}
BasicBlock *VPTransformState::CFGState::getPreheaderBBFor(VPRecipeBase *R) {
VPRegionBlock *LoopRegion = R->getParent()->getEnclosingLoopRegion();
return VPBB2IRBB[LoopRegion->getPreheaderVPBB()];
}
void VPTransformState::addNewMetadata(Instruction *To,
const Instruction *Orig) {
// If the loop was versioned with memchecks, add the corresponding no-alias
// metadata.
if (LVer && (isa<LoadInst>(Orig) || isa<StoreInst>(Orig)))
LVer->annotateInstWithNoAlias(To, Orig);
}
void VPTransformState::addMetadata(Instruction *To, Instruction *From) {
// No source instruction to transfer metadata from?
if (!From)
return;
propagateMetadata(To, From);
addNewMetadata(To, From);
}
void VPTransformState::addMetadata(ArrayRef<Value *> To, Instruction *From) {
// No source instruction to transfer metadata from?
if (!From)
return;
for (Value *V : To) {
if (Instruction *I = dyn_cast<Instruction>(V))
addMetadata(I, From);
}
}
void VPTransformState::setDebugLocFrom(DebugLoc DL) {
const DILocation *DIL = DL;
// When a FSDiscriminator is enabled, we don't need to add the multiply
// factors to the discriminators.
if (DIL &&
Builder.GetInsertBlock()
->getParent()
->shouldEmitDebugInfoForProfiling() &&
!EnableFSDiscriminator) {
// FIXME: For scalable vectors, assume vscale=1.
auto NewDIL =
DIL->cloneByMultiplyingDuplicationFactor(UF * VF.getKnownMinValue());
if (NewDIL)
Builder.SetCurrentDebugLocation(*NewDIL);
else
LLVM_DEBUG(dbgs() << "Failed to create new discriminator: "
<< DIL->getFilename() << " Line: " << DIL->getLine());
} else
Builder.SetCurrentDebugLocation(DIL);
}
void VPTransformState::packScalarIntoVectorValue(VPValue *Def,
const VPIteration &Instance) {
Value *ScalarInst = get(Def, Instance);
Value *VectorValue = get(Def, Instance.Part);
VectorValue = Builder.CreateInsertElement(
VectorValue, ScalarInst, Instance.Lane.getAsRuntimeExpr(Builder, VF));
set(Def, VectorValue, Instance.Part);
}
BasicBlock *
VPBasicBlock::createEmptyBasicBlock(VPTransformState::CFGState &CFG) {
// BB stands for IR BasicBlocks. VPBB stands for VPlan VPBasicBlocks.
// Pred stands for Predessor. Prev stands for Previous - last visited/created.
BasicBlock *PrevBB = CFG.PrevBB;
BasicBlock *NewBB = BasicBlock::Create(PrevBB->getContext(), getName(),
PrevBB->getParent(), CFG.ExitBB);
LLVM_DEBUG(dbgs() << "LV: created " << NewBB->getName() << '\n');
// Hook up the new basic block to its predecessors.
for (VPBlockBase *PredVPBlock : getHierarchicalPredecessors()) {
VPBasicBlock *PredVPBB = PredVPBlock->getExitingBasicBlock();
auto &PredVPSuccessors = PredVPBB->getHierarchicalSuccessors();
BasicBlock *PredBB = CFG.VPBB2IRBB[PredVPBB];
assert(PredBB && "Predecessor basic-block not found building successor.");
auto *PredBBTerminator = PredBB->getTerminator();
LLVM_DEBUG(dbgs() << "LV: draw edge from" << PredBB->getName() << '\n');
auto *TermBr = dyn_cast<BranchInst>(PredBBTerminator);
if (isa<UnreachableInst>(PredBBTerminator)) {
assert(PredVPSuccessors.size() == 1 &&
"Predecessor ending w/o branch must have single successor.");
DebugLoc DL = PredBBTerminator->getDebugLoc();
PredBBTerminator->eraseFromParent();
auto *Br = BranchInst::Create(NewBB, PredBB);
Br->setDebugLoc(DL);
} else if (TermBr && !TermBr->isConditional()) {
TermBr->setSuccessor(0, NewBB);
} else {
// Set each forward successor here when it is created, excluding
// backedges. A backward successor is set when the branch is created.
unsigned idx = PredVPSuccessors.front() == this ? 0 : 1;
assert(!TermBr->getSuccessor(idx) &&
"Trying to reset an existing successor block.");
TermBr->setSuccessor(idx, NewBB);
}
}
return NewBB;
}
void VPBasicBlock::execute(VPTransformState *State) {
bool Replica = State->Instance && !State->Instance->isFirstIteration();
VPBasicBlock *PrevVPBB = State->CFG.PrevVPBB;
VPBlockBase *SingleHPred = nullptr;
BasicBlock *NewBB = State->CFG.PrevBB; // Reuse it if possible.
auto IsLoopRegion = [](VPBlockBase *BB) {
auto *R = dyn_cast<VPRegionBlock>(BB);
return R && !R->isReplicator();
};
// 1. Create an IR basic block, or reuse the last one or ExitBB if possible.
if (getPlan()->getVectorLoopRegion()->getSingleSuccessor() == this) {
// ExitBB can be re-used for the exit block of the Plan.
NewBB = State->CFG.ExitBB;
State->CFG.PrevBB = NewBB;
State->Builder.SetInsertPoint(NewBB->getFirstNonPHI());
// Update the branch instruction in the predecessor to branch to ExitBB.
VPBlockBase *PredVPB = getSingleHierarchicalPredecessor();
VPBasicBlock *ExitingVPBB = PredVPB->getExitingBasicBlock();
assert(PredVPB->getSingleSuccessor() == this &&
"predecessor must have the current block as only successor");
BasicBlock *ExitingBB = State->CFG.VPBB2IRBB[ExitingVPBB];
// The Exit block of a loop is always set to be successor 0 of the Exiting
// block.
cast<BranchInst>(ExitingBB->getTerminator())->setSuccessor(0, NewBB);
} else if (PrevVPBB && /* A */
!((SingleHPred = getSingleHierarchicalPredecessor()) &&
SingleHPred->getExitingBasicBlock() == PrevVPBB &&
PrevVPBB->getSingleHierarchicalSuccessor() &&
(SingleHPred->getParent() == getEnclosingLoopRegion() &&
!IsLoopRegion(SingleHPred))) && /* B */
!(Replica && getPredecessors().empty())) { /* C */
// The last IR basic block is reused, as an optimization, in three cases:
// A. the first VPBB reuses the loop pre-header BB - when PrevVPBB is null;
// B. when the current VPBB has a single (hierarchical) predecessor which
// is PrevVPBB and the latter has a single (hierarchical) successor which
// both are in the same non-replicator region; and
// C. when the current VPBB is an entry of a region replica - where PrevVPBB
// is the exiting VPBB of this region from a previous instance, or the
// predecessor of this region.
NewBB = createEmptyBasicBlock(State->CFG);
State->Builder.SetInsertPoint(NewBB);
// Temporarily terminate with unreachable until CFG is rewired.
UnreachableInst *Terminator = State->Builder.CreateUnreachable();
// Register NewBB in its loop. In innermost loops its the same for all
// BB's.
if (State->CurrentVectorLoop)
State->CurrentVectorLoop->addBasicBlockToLoop(NewBB, *State->LI);
State->Builder.SetInsertPoint(Terminator);
State->CFG.PrevBB = NewBB;
}
// 2. Fill the IR basic block with IR instructions.
LLVM_DEBUG(dbgs() << "LV: vectorizing VPBB:" << getName()
<< " in BB:" << NewBB->getName() << '\n');
State->CFG.VPBB2IRBB[this] = NewBB;
State->CFG.PrevVPBB = this;
for (VPRecipeBase &Recipe : Recipes)
Recipe.execute(*State);
LLVM_DEBUG(dbgs() << "LV: filled BB:" << *NewBB);
}
void VPBasicBlock::dropAllReferences(VPValue *NewValue) {
for (VPRecipeBase &R : Recipes) {
for (auto *Def : R.definedValues())
Def->replaceAllUsesWith(NewValue);
for (unsigned I = 0, E = R.getNumOperands(); I != E; I++)
R.setOperand(I, NewValue);
}
}
VPBasicBlock *VPBasicBlock::splitAt(iterator SplitAt) {
assert((SplitAt == end() || SplitAt->getParent() == this) &&
"can only split at a position in the same block");
SmallVector<VPBlockBase *, 2> Succs(successors());
// First, disconnect the current block from its successors.
for (VPBlockBase *Succ : Succs)
VPBlockUtils::disconnectBlocks(this, Succ);
// Create new empty block after the block to split.
auto *SplitBlock = new VPBasicBlock(getName() + ".split");
VPBlockUtils::insertBlockAfter(SplitBlock, this);
// Add successors for block to split to new block.
for (VPBlockBase *Succ : Succs)
VPBlockUtils::connectBlocks(SplitBlock, Succ);
// Finally, move the recipes starting at SplitAt to new block.
for (VPRecipeBase &ToMove :
make_early_inc_range(make_range(SplitAt, this->end())))
ToMove.moveBefore(*SplitBlock, SplitBlock->end());
return SplitBlock;
}
VPRegionBlock *VPBasicBlock::getEnclosingLoopRegion() {
VPRegionBlock *P = getParent();
if (P && P->isReplicator()) {
P = P->getParent();
assert(!cast<VPRegionBlock>(P)->isReplicator() &&
"unexpected nested replicate regions");
}
return P;
}
static bool hasConditionalTerminator(const VPBasicBlock *VPBB) {
if (VPBB->empty()) {
assert(
VPBB->getNumSuccessors() < 2 &&
"block with multiple successors doesn't have a recipe as terminator");
return false;
}
const VPRecipeBase *R = &VPBB->back();
bool IsCondBranch = isa<VPBranchOnMaskRecipe>(R) ||
match(R, m_BranchOnCond(m_VPValue())) ||
match(R, m_BranchOnCount(m_VPValue(), m_VPValue()));
(void)IsCondBranch;
if (VPBB->getNumSuccessors() >= 2 ||
(VPBB->isExiting() && !VPBB->getParent()->isReplicator())) {
assert(IsCondBranch && "block with multiple successors not terminated by "
"conditional branch recipe");
return true;
}
assert(
!IsCondBranch &&
"block with 0 or 1 successors terminated by conditional branch recipe");
return false;
}
VPRecipeBase *VPBasicBlock::getTerminator() {
if (hasConditionalTerminator(this))
return &back();
return nullptr;
}
const VPRecipeBase *VPBasicBlock::getTerminator() const {
if (hasConditionalTerminator(this))
return &back();
return nullptr;
}
bool VPBasicBlock::isExiting() const {
return getParent() && getParent()->getExitingBasicBlock() == this;
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void VPBlockBase::printSuccessors(raw_ostream &O, const Twine &Indent) const {
if (getSuccessors().empty()) {
O << Indent << "No successors\n";
} else {
O << Indent << "Successor(s): ";
ListSeparator LS;
for (auto *Succ : getSuccessors())
O << LS << Succ->getName();
O << '\n';
}
}
void VPBasicBlock::print(raw_ostream &O, const Twine &Indent,
VPSlotTracker &SlotTracker) const {
O << Indent << getName() << ":\n";
auto RecipeIndent = Indent + " ";
for (const VPRecipeBase &Recipe : *this) {
Recipe.print(O, RecipeIndent, SlotTracker);
O << '\n';
}
printSuccessors(O, Indent);
}
#endif
static std::pair<VPBlockBase *, VPBlockBase *> cloneSESE(VPBlockBase *Entry);
// Clone the CFG for all nodes in the single-entry-single-exit region reachable
// from \p Entry, this includes cloning the blocks and their recipes. Operands
// of cloned recipes will NOT be updated. Remapping of operands must be done
// separately. Returns a pair with the the new entry and exiting blocks of the
// cloned region.
static std::pair<VPBlockBase *, VPBlockBase *> cloneSESE(VPBlockBase *Entry) {
DenseMap<VPBlockBase *, VPBlockBase *> Old2NewVPBlocks;
ReversePostOrderTraversal<VPBlockShallowTraversalWrapper<VPBlockBase *>> RPOT(
Entry);
for (VPBlockBase *BB : RPOT) {
VPBlockBase *NewBB = BB->clone();
for (VPBlockBase *Pred : BB->getPredecessors())
VPBlockUtils::connectBlocks(Old2NewVPBlocks[Pred], NewBB);
Old2NewVPBlocks[BB] = NewBB;
}
#if !defined(NDEBUG)
// Verify that the order of predecessors and successors matches in the cloned
// version.
ReversePostOrderTraversal<VPBlockShallowTraversalWrapper<VPBlockBase *>>
NewRPOT(Old2NewVPBlocks[Entry]);
for (const auto &[OldBB, NewBB] : zip(RPOT, NewRPOT)) {
for (const auto &[OldPred, NewPred] :
zip(OldBB->getPredecessors(), NewBB->getPredecessors()))
assert(NewPred == Old2NewVPBlocks[OldPred] && "Different predecessors");
for (const auto &[OldSucc, NewSucc] :
zip(OldBB->successors(), NewBB->successors()))
assert(NewSucc == Old2NewVPBlocks[OldSucc] && "Different successors");
}
#endif
return std::make_pair(Old2NewVPBlocks[Entry],
Old2NewVPBlocks[*reverse(RPOT).begin()]);
}
VPRegionBlock *VPRegionBlock::clone() {
const auto &[NewEntry, NewExiting] = cloneSESE(getEntry());
auto *NewRegion =
new VPRegionBlock(NewEntry, NewExiting, getName(), isReplicator());
for (VPBlockBase *Block : vp_depth_first_shallow(NewEntry))
Block->setParent(NewRegion);
return NewRegion;
}
void VPRegionBlock::dropAllReferences(VPValue *NewValue) {
for (VPBlockBase *Block : vp_depth_first_shallow(Entry))
// Drop all references in VPBasicBlocks and replace all uses with
// DummyValue.
Block->dropAllReferences(NewValue);
}
void VPRegionBlock::execute(VPTransformState *State) {
ReversePostOrderTraversal<VPBlockShallowTraversalWrapper<VPBlockBase *>>
RPOT(Entry);
if (!isReplicator()) {
// Create and register the new vector loop.
Loop *PrevLoop = State->CurrentVectorLoop;
State->CurrentVectorLoop = State->LI->AllocateLoop();
BasicBlock *VectorPH = State->CFG.VPBB2IRBB[getPreheaderVPBB()];
Loop *ParentLoop = State->LI->getLoopFor(VectorPH);
// Insert the new loop into the loop nest and register the new basic blocks
// before calling any utilities such as SCEV that require valid LoopInfo.
if (ParentLoop)
ParentLoop->addChildLoop(State->CurrentVectorLoop);
else
State->LI->addTopLevelLoop(State->CurrentVectorLoop);
// Visit the VPBlocks connected to "this", starting from it.
for (VPBlockBase *Block : RPOT) {
LLVM_DEBUG(dbgs() << "LV: VPBlock in RPO " << Block->getName() << '\n');
Block->execute(State);
}
State->CurrentVectorLoop = PrevLoop;
return;
}
assert(!State->Instance && "Replicating a Region with non-null instance.");
// Enter replicating mode.
State->Instance = VPIteration(0, 0);
for (unsigned Part = 0, UF = State->UF; Part < UF; ++Part) {
State->Instance->Part = Part;
assert(!State->VF.isScalable() && "VF is assumed to be non scalable.");
for (unsigned Lane = 0, VF = State->VF.getKnownMinValue(); Lane < VF;
++Lane) {
State->Instance->Lane = VPLane(Lane, VPLane::Kind::First);
// Visit the VPBlocks connected to \p this, starting from it.
for (VPBlockBase *Block : RPOT) {
LLVM_DEBUG(dbgs() << "LV: VPBlock in RPO " << Block->getName() << '\n');
Block->execute(State);
}
}
}
// Exit replicating mode.
State->Instance.reset();
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void VPRegionBlock::print(raw_ostream &O, const Twine &Indent,
VPSlotTracker &SlotTracker) const {
O << Indent << (isReplicator() ? "<xVFxUF> " : "<x1> ") << getName() << ": {";
auto NewIndent = Indent + " ";
for (auto *BlockBase : vp_depth_first_shallow(Entry)) {
O << '\n';
BlockBase->print(O, NewIndent, SlotTracker);
}
O << Indent << "}\n";
printSuccessors(O, Indent);
}
#endif
VPlan::~VPlan() {
for (auto &KV : LiveOuts)
delete KV.second;
LiveOuts.clear();
if (Entry) {
VPValue DummyValue;
for (VPBlockBase *Block : vp_depth_first_shallow(Entry))
Block->dropAllReferences(&DummyValue);
VPBlockBase::deleteCFG(Entry);
Preheader->dropAllReferences(&DummyValue);
delete Preheader;
}
for (VPValue *VPV : VPLiveInsToFree)
delete VPV;
if (BackedgeTakenCount)
delete BackedgeTakenCount;
}
VPlanPtr VPlan::createInitialVPlan(const SCEV *TripCount, ScalarEvolution &SE) {
VPBasicBlock *Preheader = new VPBasicBlock("ph");
VPBasicBlock *VecPreheader = new VPBasicBlock("vector.ph");
auto Plan = std::make_unique<VPlan>(Preheader, VecPreheader);
Plan->TripCount =
vputils::getOrCreateVPValueForSCEVExpr(*Plan, TripCount, SE);
// Create empty VPRegionBlock, to be filled during processing later.
auto *TopRegion = new VPRegionBlock("vector loop", false /*isReplicator*/);
VPBlockUtils::insertBlockAfter(TopRegion, VecPreheader);
VPBasicBlock *MiddleVPBB = new VPBasicBlock("middle.block");
VPBlockUtils::insertBlockAfter(MiddleVPBB, TopRegion);
return Plan;
}
void VPlan::prepareToExecute(Value *TripCountV, Value *VectorTripCountV,
Value *CanonicalIVStartValue,
VPTransformState &State) {
// Check if the backedge taken count is needed, and if so build it.
if (BackedgeTakenCount && BackedgeTakenCount->getNumUsers()) {
IRBuilder<> Builder(State.CFG.PrevBB->getTerminator());
auto *TCMO = Builder.CreateSub(TripCountV,
ConstantInt::get(TripCountV->getType(), 1),
"trip.count.minus.1");
BackedgeTakenCount->setUnderlyingValue(TCMO);
}
VectorTripCount.setUnderlyingValue(VectorTripCountV);
IRBuilder<> Builder(State.CFG.PrevBB->getTerminator());
// FIXME: Model VF * UF computation completely in VPlan.
VFxUF.setUnderlyingValue(
createStepForVF(Builder, TripCountV->getType(), State.VF, State.UF));
// When vectorizing the epilogue loop, the canonical induction start value
// needs to be changed from zero to the value after the main vector loop.
// FIXME: Improve modeling for canonical IV start values in the epilogue loop.
if (CanonicalIVStartValue) {
VPValue *VPV = getOrAddLiveIn(CanonicalIVStartValue);
auto *IV = getCanonicalIV();
assert(all_of(IV->users(),
[](const VPUser *U) {
return isa<VPScalarIVStepsRecipe>(U) ||
isa<VPScalarCastRecipe>(U) ||
isa<VPDerivedIVRecipe>(U) ||
cast<VPInstruction>(U)->getOpcode() ==
Instruction::Add;
}) &&
"the canonical IV should only be used by its increment or "
"ScalarIVSteps when resetting the start value");
IV->setOperand(0, VPV);
}
}
/// Generate the code inside the preheader and body of the vectorized loop.
/// Assumes a single pre-header basic-block was created for this. Introduce
/// additional basic-blocks as needed, and fill them all.
void VPlan::execute(VPTransformState *State) {
// Initialize CFG state.
State->CFG.PrevVPBB = nullptr;
State->CFG.ExitBB = State->CFG.PrevBB->getSingleSuccessor();
BasicBlock *VectorPreHeader = State->CFG.PrevBB;
State->Builder.SetInsertPoint(VectorPreHeader->getTerminator());
// Generate code in the loop pre-header and body.
for (VPBlockBase *Block : vp_depth_first_shallow(Entry))
Block->execute(State);
VPBasicBlock *LatchVPBB = getVectorLoopRegion()->getExitingBasicBlock();
BasicBlock *VectorLatchBB = State->CFG.VPBB2IRBB[LatchVPBB];
// Fix the latch value of canonical, reduction and first-order recurrences
// phis in the vector loop.
VPBasicBlock *Header = getVectorLoopRegion()->getEntryBasicBlock();
for (VPRecipeBase &R : Header->phis()) {
// Skip phi-like recipes that generate their backedege values themselves.
if (isa<VPWidenPHIRecipe>(&R))
continue;
if (isa<VPWidenPointerInductionRecipe>(&R) ||
isa<VPWidenIntOrFpInductionRecipe>(&R)) {
PHINode *Phi = nullptr;
if (isa<VPWidenIntOrFpInductionRecipe>(&R)) {
Phi = cast<PHINode>(State->get(R.getVPSingleValue(), 0));
} else {
auto *WidenPhi = cast<VPWidenPointerInductionRecipe>(&R);
assert(!WidenPhi->onlyScalarsGenerated(State->VF.isScalable()) &&
"recipe generating only scalars should have been replaced");
auto *GEP = cast<GetElementPtrInst>(State->get(WidenPhi, 0));
Phi = cast<PHINode>(GEP->getPointerOperand());
}
Phi->setIncomingBlock(1, VectorLatchBB);
// Move the last step to the end of the latch block. This ensures
// consistent placement of all induction updates.
Instruction *Inc = cast<Instruction>(Phi->getIncomingValue(1));
Inc->moveBefore(VectorLatchBB->getTerminator()->getPrevNode());
continue;
}
auto *PhiR = cast<VPHeaderPHIRecipe>(&R);
// For canonical IV, first-order recurrences and in-order reduction phis,
// only a single part is generated, which provides the last part from the
// previous iteration. For non-ordered reductions all UF parts are
// generated.
bool SinglePartNeeded = isa<VPCanonicalIVPHIRecipe>(PhiR) ||
isa<VPFirstOrderRecurrencePHIRecipe>(PhiR) ||
(isa<VPReductionPHIRecipe>(PhiR) &&
cast<VPReductionPHIRecipe>(PhiR)->isOrdered());
bool NeedsScalar = isa<VPCanonicalIVPHIRecipe>(PhiR) ||
(isa<VPReductionPHIRecipe>(PhiR) &&
cast<VPReductionPHIRecipe>(PhiR)->isInLoop());
unsigned LastPartForNewPhi = SinglePartNeeded ? 1 : State->UF;
for (unsigned Part = 0; Part < LastPartForNewPhi; ++Part) {
Value *Phi = State->get(PhiR, Part, NeedsScalar);
Value *Val =
State->get(PhiR->getBackedgeValue(),
SinglePartNeeded ? State->UF - 1 : Part, NeedsScalar);
cast<PHINode>(Phi)->addIncoming(Val, VectorLatchBB);
}
}
// We do not attempt to preserve DT for outer loop vectorization currently.
if (!EnableVPlanNativePath) {
BasicBlock *VectorHeaderBB = State->CFG.VPBB2IRBB[Header];
State->DT->addNewBlock(VectorHeaderBB, VectorPreHeader);
updateDominatorTree(State->DT, VectorHeaderBB, VectorLatchBB,
State->CFG.ExitBB);
}
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void VPlan::printLiveIns(raw_ostream &O) const {
VPSlotTracker SlotTracker(this);
if (VFxUF.getNumUsers() > 0) {
O << "\nLive-in ";
VFxUF.printAsOperand(O, SlotTracker);
O << " = VF * UF";
}
if (VectorTripCount.getNumUsers() > 0) {
O << "\nLive-in ";
VectorTripCount.printAsOperand(O, SlotTracker);
O << " = vector-trip-count";
}
if (BackedgeTakenCount && BackedgeTakenCount->getNumUsers()) {
O << "\nLive-in ";
BackedgeTakenCount->printAsOperand(O, SlotTracker);
O << " = backedge-taken count";
}
O << "\n";
if (TripCount->isLiveIn())
O << "Live-in ";
TripCount->printAsOperand(O, SlotTracker);
O << " = original trip-count";
O << "\n";
}
LLVM_DUMP_METHOD
void VPlan::print(raw_ostream &O) const {
VPSlotTracker SlotTracker(this);
O << "VPlan '" << getName() << "' {";
printLiveIns(O);
if (!getPreheader()->empty()) {
O << "\n";
getPreheader()->print(O, "", SlotTracker);
}
for (const VPBlockBase *Block : vp_depth_first_shallow(getEntry())) {
O << '\n';
Block->print(O, "", SlotTracker);
}
if (!LiveOuts.empty())
O << "\n";
for (const auto &KV : LiveOuts) {
KV.second->print(O, SlotTracker);
}
O << "}\n";
}
std::string VPlan::getName() const {
std::string Out;
raw_string_ostream RSO(Out);
RSO << Name << " for ";
if (!VFs.empty()) {
RSO << "VF={" << VFs[0];
for (ElementCount VF : drop_begin(VFs))
RSO << "," << VF;
RSO << "},";
}
if (UFs.empty()) {
RSO << "UF>=1";
} else {
RSO << "UF={" << UFs[0];
for (unsigned UF : drop_begin(UFs))
RSO << "," << UF;
RSO << "}";
}
return Out;
}
LLVM_DUMP_METHOD
void VPlan::printDOT(raw_ostream &O) const {
VPlanPrinter Printer(O, *this);
Printer.dump();
}
LLVM_DUMP_METHOD
void VPlan::dump() const { print(dbgs()); }
#endif
void VPlan::addLiveOut(PHINode *PN, VPValue *V) {
assert(LiveOuts.count(PN) == 0 && "an exit value for PN already exists");
LiveOuts.insert({PN, new VPLiveOut(PN, V)});
}
void VPlan::updateDominatorTree(DominatorTree *DT, BasicBlock *LoopHeaderBB,
BasicBlock *LoopLatchBB,
BasicBlock *LoopExitBB) {
// The vector body may be more than a single basic-block by this point.
// Update the dominator tree information inside the vector body by propagating
// it from header to latch, expecting only triangular control-flow, if any.
BasicBlock *PostDomSucc = nullptr;
for (auto *BB = LoopHeaderBB; BB != LoopLatchBB; BB = PostDomSucc) {
// Get the list of successors of this block.
std::vector<BasicBlock *> Succs(succ_begin(BB), succ_end(BB));
assert(Succs.size() <= 2 &&
"Basic block in vector loop has more than 2 successors.");
PostDomSucc = Succs[0];
if (Succs.size() == 1) {
assert(PostDomSucc->getSinglePredecessor() &&
"PostDom successor has more than one predecessor.");
DT->addNewBlock(PostDomSucc, BB);
continue;
}
BasicBlock *InterimSucc = Succs[1];
if (PostDomSucc->getSingleSuccessor() == InterimSucc) {
PostDomSucc = Succs[1];
InterimSucc = Succs[0];
}
assert(InterimSucc->getSingleSuccessor() == PostDomSucc &&
"One successor of a basic block does not lead to the other.");
assert(InterimSucc->getSinglePredecessor() &&
"Interim successor has more than one predecessor.");
assert(PostDomSucc->hasNPredecessors(2) &&
"PostDom successor has more than two predecessors.");
DT->addNewBlock(InterimSucc, BB);
DT->addNewBlock(PostDomSucc, BB);
}
// Latch block is a new dominator for the loop exit.
DT->changeImmediateDominator(LoopExitBB, LoopLatchBB);
assert(DT->verify(DominatorTree::VerificationLevel::Fast));
}
static void remapOperands(VPBlockBase *Entry, VPBlockBase *NewEntry,
DenseMap<VPValue *, VPValue *> &Old2NewVPValues) {
// Update the operands of all cloned recipes starting at NewEntry. This
// traverses all reachable blocks. This is done in two steps, to handle cycles
// in PHI recipes.
ReversePostOrderTraversal<VPBlockDeepTraversalWrapper<VPBlockBase *>>
OldDeepRPOT(Entry);
ReversePostOrderTraversal<VPBlockDeepTraversalWrapper<VPBlockBase *>>
NewDeepRPOT(NewEntry);
// First, collect all mappings from old to new VPValues defined by cloned
// recipes.
for (const auto &[OldBB, NewBB] :
zip(VPBlockUtils::blocksOnly<VPBasicBlock>(OldDeepRPOT),
VPBlockUtils::blocksOnly<VPBasicBlock>(NewDeepRPOT))) {
assert(OldBB->getRecipeList().size() == NewBB->getRecipeList().size() &&
"blocks must have the same number of recipes");
for (const auto &[OldR, NewR] : zip(*OldBB, *NewBB)) {
assert(OldR.getNumOperands() == NewR.getNumOperands() &&
"recipes must have the same number of operands");
assert(OldR.getNumDefinedValues() == NewR.getNumDefinedValues() &&
"recipes must define the same number of operands");
for (const auto &[OldV, NewV] :
zip(OldR.definedValues(), NewR.definedValues()))
Old2NewVPValues[OldV] = NewV;
}
}
// Update all operands to use cloned VPValues.
for (VPBasicBlock *NewBB :
VPBlockUtils::blocksOnly<VPBasicBlock>(NewDeepRPOT)) {
for (VPRecipeBase &NewR : *NewBB)
for (unsigned I = 0, E = NewR.getNumOperands(); I != E; ++I) {
VPValue *NewOp = Old2NewVPValues.lookup(NewR.getOperand(I));
NewR.setOperand(I, NewOp);
}
}
}
VPlan *VPlan::duplicate() {
// Clone blocks.
VPBasicBlock *NewPreheader = Preheader->clone();
const auto &[NewEntry, __] = cloneSESE(Entry);
// Create VPlan, clone live-ins and remap operands in the cloned blocks.
auto *NewPlan = new VPlan(NewPreheader, cast<VPBasicBlock>(NewEntry));
DenseMap<VPValue *, VPValue *> Old2NewVPValues;
for (VPValue *OldLiveIn : VPLiveInsToFree) {
Old2NewVPValues[OldLiveIn] =
NewPlan->getOrAddLiveIn(OldLiveIn->getLiveInIRValue());
}
Old2NewVPValues[&VectorTripCount] = &NewPlan->VectorTripCount;
Old2NewVPValues[&VFxUF] = &NewPlan->VFxUF;
if (BackedgeTakenCount) {
NewPlan->BackedgeTakenCount = new VPValue();
Old2NewVPValues[BackedgeTakenCount] = NewPlan->BackedgeTakenCount;
}
assert(TripCount && "trip count must be set");
if (TripCount->isLiveIn())
Old2NewVPValues[TripCount] =
NewPlan->getOrAddLiveIn(TripCount->getLiveInIRValue());
// else NewTripCount will be created and inserted into Old2NewVPValues when
// TripCount is cloned. In any case NewPlan->TripCount is updated below.
remapOperands(Preheader, NewPreheader, Old2NewVPValues);
remapOperands(Entry, NewEntry, Old2NewVPValues);
// Clone live-outs.
for (const auto &[_, LO] : LiveOuts)
NewPlan->addLiveOut(LO->getPhi(), Old2NewVPValues[LO->getOperand(0)]);
// Initialize remaining fields of cloned VPlan.
NewPlan->VFs = VFs;
NewPlan->UFs = UFs;
// TODO: Adjust names.
NewPlan->Name = Name;
assert(Old2NewVPValues.contains(TripCount) &&
"TripCount must have been added to Old2NewVPValues");
NewPlan->TripCount = Old2NewVPValues[TripCount];
return NewPlan;
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
Twine VPlanPrinter::getUID(const VPBlockBase *Block) {
return (isa<VPRegionBlock>(Block) ? "cluster_N" : "N") +
Twine(getOrCreateBID(Block));
}
Twine VPlanPrinter::getOrCreateName(const VPBlockBase *Block) {
const std::string &Name = Block->getName();
if (!Name.empty())
return Name;
return "VPB" + Twine(getOrCreateBID(Block));
}
void VPlanPrinter::dump() {
Depth = 1;
bumpIndent(0);
OS << "digraph VPlan {\n";
OS << "graph [labelloc=t, fontsize=30; label=\"Vectorization Plan";
if (!Plan.getName().empty())
OS << "\\n" << DOT::EscapeString(Plan.getName());
{
// Print live-ins.
std::string Str;
raw_string_ostream SS(Str);
Plan.printLiveIns(SS);
SmallVector<StringRef, 0> Lines;
StringRef(Str).rtrim('\n').split(Lines, "\n");
for (auto Line : Lines)
OS << DOT::EscapeString(Line.str()) << "\\n";
}
OS << "\"]\n";
OS << "node [shape=rect, fontname=Courier, fontsize=30]\n";
OS << "edge [fontname=Courier, fontsize=30]\n";
OS << "compound=true\n";
dumpBlock(Plan.getPreheader());
for (const VPBlockBase *Block : vp_depth_first_shallow(Plan.getEntry()))
dumpBlock(Block);
OS << "}\n";
}
void VPlanPrinter::dumpBlock(const VPBlockBase *Block) {
if (const VPBasicBlock *BasicBlock = dyn_cast<VPBasicBlock>(Block))
dumpBasicBlock(BasicBlock);
else if (const VPRegionBlock *Region = dyn_cast<VPRegionBlock>(Block))
dumpRegion(Region);
else
llvm_unreachable("Unsupported kind of VPBlock.");
}
void VPlanPrinter::drawEdge(const VPBlockBase *From, const VPBlockBase *To,
bool Hidden, const Twine &Label) {
// Due to "dot" we print an edge between two regions as an edge between the
// exiting basic block and the entry basic of the respective regions.
const VPBlockBase *Tail = From->getExitingBasicBlock();
const VPBlockBase *Head = To->getEntryBasicBlock();
OS << Indent << getUID(Tail) << " -> " << getUID(Head);
OS << " [ label=\"" << Label << '\"';
if (Tail != From)
OS << " ltail=" << getUID(From);
if (Head != To)
OS << " lhead=" << getUID(To);
if (Hidden)
OS << "; splines=none";
OS << "]\n";
}
void VPlanPrinter::dumpEdges(const VPBlockBase *Block) {
auto &Successors = Block->getSuccessors();
if (Successors.size() == 1)
drawEdge(Block, Successors.front(), false, "");
else if (Successors.size() == 2) {
drawEdge(Block, Successors.front(), false, "T");
drawEdge(Block, Successors.back(), false, "F");
} else {
unsigned SuccessorNumber = 0;
for (auto *Successor : Successors)
drawEdge(Block, Successor, false, Twine(SuccessorNumber++));
}
}
void VPlanPrinter::dumpBasicBlock(const VPBasicBlock *BasicBlock) {
// Implement dot-formatted dump by performing plain-text dump into the
// temporary storage followed by some post-processing.
OS << Indent << getUID(BasicBlock) << " [label =\n";
bumpIndent(1);
std::string Str;
raw_string_ostream SS(Str);
// Use no indentation as we need to wrap the lines into quotes ourselves.
BasicBlock->print(SS, "", SlotTracker);
// We need to process each line of the output separately, so split
// single-string plain-text dump.
SmallVector<StringRef, 0> Lines;
StringRef(Str).rtrim('\n').split(Lines, "\n");
auto EmitLine = [&](StringRef Line, StringRef Suffix) {
OS << Indent << '"' << DOT::EscapeString(Line.str()) << "\\l\"" << Suffix;
};
// Don't need the "+" after the last line.
for (auto Line : make_range(Lines.begin(), Lines.end() - 1))
EmitLine(Line, " +\n");
EmitLine(Lines.back(), "\n");
bumpIndent(-1);
OS << Indent << "]\n";
dumpEdges(BasicBlock);
}
void VPlanPrinter::dumpRegion(const VPRegionBlock *Region) {
OS << Indent << "subgraph " << getUID(Region) << " {\n";
bumpIndent(1);
OS << Indent << "fontname=Courier\n"
<< Indent << "label=\""
<< DOT::EscapeString(Region->isReplicator() ? "<xVFxUF> " : "<x1> ")
<< DOT::EscapeString(Region->getName()) << "\"\n";
// Dump the blocks of the region.
assert(Region->getEntry() && "Region contains no inner blocks.");
for (const VPBlockBase *Block : vp_depth_first_shallow(Region->getEntry()))
dumpBlock(Block);
bumpIndent(-1);
OS << Indent << "}\n";
dumpEdges(Region);
}
void VPlanIngredient::print(raw_ostream &O) const {
if (auto *Inst = dyn_cast<Instruction>(V)) {
if (!Inst->getType()->isVoidTy()) {
Inst->printAsOperand(O, false);
O << " = ";
}
O << Inst->getOpcodeName() << " ";
unsigned E = Inst->getNumOperands();
if (E > 0) {
Inst->getOperand(0)->printAsOperand(O, false);
for (unsigned I = 1; I < E; ++I)
Inst->getOperand(I)->printAsOperand(O << ", ", false);
}
} else // !Inst
V->printAsOperand(O, false);
}
#endif
template void DomTreeBuilder::Calculate<VPDominatorTree>(VPDominatorTree &DT);
void VPValue::replaceAllUsesWith(VPValue *New) {
replaceUsesWithIf(New, [](VPUser &, unsigned) { return true; });
}
void VPValue::replaceUsesWithIf(
VPValue *New,
llvm::function_ref<bool(VPUser &U, unsigned Idx)> ShouldReplace) {
// Note that this early exit is required for correctness; the implementation
// below relies on the number of users for this VPValue to decrease, which
// isn't the case if this == New.
if (this == New)
return;
for (unsigned J = 0; J < getNumUsers();) {
VPUser *User = Users[J];
bool RemovedUser = false;
for (unsigned I = 0, E = User->getNumOperands(); I < E; ++I) {
if (User->getOperand(I) != this || !ShouldReplace(*User, I))
continue;
RemovedUser = true;
User->setOperand(I, New);
}
// If a user got removed after updating the current user, the next user to
// update will be moved to the current position, so we only need to
// increment the index if the number of users did not change.
if (!RemovedUser)
J++;
}
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void VPValue::printAsOperand(raw_ostream &OS, VPSlotTracker &Tracker) const {
if (const Value *UV = getUnderlyingValue()) {
OS << "ir<";
UV->printAsOperand(OS, false);
OS << ">";
return;
}
unsigned Slot = Tracker.getSlot(this);
if (Slot == unsigned(-1))
OS << "<badref>";
else
OS << "vp<%" << Tracker.getSlot(this) << ">";
}
void VPUser::printOperands(raw_ostream &O, VPSlotTracker &SlotTracker) const {
interleaveComma(operands(), O, [&O, &SlotTracker](VPValue *Op) {
Op->printAsOperand(O, SlotTracker);
});
}
#endif
void VPInterleavedAccessInfo::visitRegion(VPRegionBlock *Region,
Old2NewTy &Old2New,
InterleavedAccessInfo &IAI) {
ReversePostOrderTraversal<VPBlockShallowTraversalWrapper<VPBlockBase *>>
RPOT(Region->getEntry());
for (VPBlockBase *Base : RPOT) {
visitBlock(Base, Old2New, IAI);
}
}
void VPInterleavedAccessInfo::visitBlock(VPBlockBase *Block, Old2NewTy &Old2New,
InterleavedAccessInfo &IAI) {
if (VPBasicBlock *VPBB = dyn_cast<VPBasicBlock>(Block)) {
for (VPRecipeBase &VPI : *VPBB) {
if (isa<VPWidenPHIRecipe>(&VPI))
continue;
assert(isa<VPInstruction>(&VPI) && "Can only handle VPInstructions");
auto *VPInst = cast<VPInstruction>(&VPI);
auto *Inst = dyn_cast_or_null<Instruction>(VPInst->getUnderlyingValue());
if (!Inst)
continue;
auto *IG = IAI.getInterleaveGroup(Inst);
if (!IG)
continue;
auto NewIGIter = Old2New.find(IG);
if (NewIGIter == Old2New.end())
Old2New[IG] = new InterleaveGroup<VPInstruction>(
IG->getFactor(), IG->isReverse(), IG->getAlign());
if (Inst == IG->getInsertPos())
Old2New[IG]->setInsertPos(VPInst);
InterleaveGroupMap[VPInst] = Old2New[IG];
InterleaveGroupMap[VPInst]->insertMember(
VPInst, IG->getIndex(Inst),
Align(IG->isReverse() ? (-1) * int(IG->getFactor())
: IG->getFactor()));
}
} else if (VPRegionBlock *Region = dyn_cast<VPRegionBlock>(Block))
visitRegion(Region, Old2New, IAI);
else
llvm_unreachable("Unsupported kind of VPBlock.");
}
VPInterleavedAccessInfo::VPInterleavedAccessInfo(VPlan &Plan,
InterleavedAccessInfo &IAI) {
Old2NewTy Old2New;
visitRegion(Plan.getVectorLoopRegion(), Old2New, IAI);
}
void VPSlotTracker::assignSlot(const VPValue *V) {
assert(!Slots.contains(V) && "VPValue already has a slot!");
Slots[V] = NextSlot++;
}
void VPSlotTracker::assignSlots(const VPlan &Plan) {
if (Plan.VFxUF.getNumUsers() > 0)
assignSlot(&Plan.VFxUF);
assignSlot(&Plan.VectorTripCount);
if (Plan.BackedgeTakenCount)
assignSlot(Plan.BackedgeTakenCount);
assignSlots(Plan.getPreheader());
ReversePostOrderTraversal<VPBlockDeepTraversalWrapper<const VPBlockBase *>>
RPOT(VPBlockDeepTraversalWrapper<const VPBlockBase *>(Plan.getEntry()));
for (const VPBasicBlock *VPBB :
VPBlockUtils::blocksOnly<const VPBasicBlock>(RPOT))
assignSlots(VPBB);
}
void VPSlotTracker::assignSlots(const VPBasicBlock *VPBB) {
for (const VPRecipeBase &Recipe : *VPBB)
for (VPValue *Def : Recipe.definedValues())
assignSlot(Def);
}
bool vputils::onlyFirstLaneUsed(const VPValue *Def) {
return all_of(Def->users(),
[Def](const VPUser *U) { return U->onlyFirstLaneUsed(Def); });
}
bool vputils::onlyFirstPartUsed(const VPValue *Def) {
return all_of(Def->users(),
[Def](const VPUser *U) { return U->onlyFirstPartUsed(Def); });
}
VPValue *vputils::getOrCreateVPValueForSCEVExpr(VPlan &Plan, const SCEV *Expr,
ScalarEvolution &SE) {
if (auto *Expanded = Plan.getSCEVExpansion(Expr))
return Expanded;
VPValue *Expanded = nullptr;
if (auto *E = dyn_cast<SCEVConstant>(Expr))
Expanded = Plan.getOrAddLiveIn(E->getValue());
else if (auto *E = dyn_cast<SCEVUnknown>(Expr))
Expanded = Plan.getOrAddLiveIn(E->getValue());
else {
Expanded = new VPExpandSCEVRecipe(Expr, SE);
Plan.getPreheader()->appendRecipe(Expanded->getDefiningRecipe());
}
Plan.addSCEVExpansion(Expr, Expanded);
return Expanded;
}
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