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llvm-project/llvm/lib/Transforms/Vectorize/VecUtils.cpp

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//===- VecUtils.cpp --- Vectorization Utilities ---------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "SLP"
#include "VecUtils.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/ScalarEvolutionExpressions.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/Analysis/Verifier.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/Value.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetLibraryInfo.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/Local.h"
#include <algorithm>
#include <map>
using namespace llvm;
static const unsigned MinVecRegSize = 128;
static const unsigned RecursionMaxDepth = 6;
namespace llvm {
BoUpSLP::BoUpSLP(BasicBlock *Bb, ScalarEvolution *S, DataLayout *Dl,
TargetTransformInfo *Tti, AliasAnalysis *Aa, Loop *Lp) :
Builder(S->getContext()), BB(Bb), SE(S), DL(Dl), TTI(Tti), AA(Aa), L(Lp) {
numberInstructions();
}
void BoUpSLP::numberInstructions() {
int 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");
}
}
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;
// Check that A and B are of the same type.
if (PtrA->getType() != PtrB->getType()) return false;
// Calculate the distance.
const SCEV *PtrSCEVA = SE->getSCEV(PtrA);
const SCEV *PtrSCEVB = SE->getSCEV(PtrB);
const SCEV *OffsetSCEV = SE->getMinusSCEV(PtrSCEVA, PtrSCEVB);
const SCEVConstant *ConstOffSCEV = dyn_cast<SCEVConstant>(OffsetSCEV);
// Non constant distance.
if (!ConstOffSCEV) return false;
int64_t Offset = ConstOffSCEV->getValue()->getSExtValue();
Type *Ty = cast<PointerType>(PtrA->getType())->getElementType();
// The Instructions are connsecutive if the size of the first load/store is
// the same as the offset.
int64_t Sz = DL->getTypeStoreSize(Ty);
return ((-Offset) == Sz);
}
bool BoUpSLP::vectorizeStoreChain(ArrayRef<Value *> Chain, int CostThreshold) {
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;
bool Changed = false;
// Look for profitable vectorizable trees at all offsets, starting at zero.
for (unsigned i = 0, e = Chain.size(); i < e; ++i) {
if (i + VF > e) return Changed;
DEBUG(dbgs()<<"SLP: Analyzing " << VF << " stores at offset "<< i << "\n");
ArrayRef<Value *> Operands = Chain.slice(i, VF);
int Cost = getTreeCost(Operands);
DEBUG(dbgs() << "SLP: Found cost=" << Cost << " for VF=" << VF << "\n");
if (Cost < CostThreshold) {
DEBUG(dbgs() << "SLP: Decided to vectorize cost=" << Cost << "\n");
Builder.SetInsertPoint(getInsertionPoint(getLastIndex(Operands,VF)));
vectorizeTree(Operands, VF);
i += VF - 1;
Changed = true;
}
}
return Changed;
}
bool BoUpSLP::vectorizeStores(ArrayRef<StoreInst *> Stores, int costThreshold) {
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.
ValueSet VectorizedStores;
bool Changed = false;
// Do a quadratic search on all of the given stores and find
// all of the pairs of loads 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 (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.
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);
// Mark the vectorized stores so that we don't vectorize them again.
if (Vectorized)
VectorizedStores.insert(Operands.begin(), Operands.end());
Changed |= Vectorized;
}
return Changed;
}
int BoUpSLP::getScalarizationCost(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 getScalarizationCost(VecTy);
}
int BoUpSLP::getScalarizationCost(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;
}
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::isUnsafeToSink(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;
}
void BoUpSLP::vectorizeArith(ArrayRef<Value *> Operands) {
int LastIdx = getLastIndex(Operands, Operands.size());
Instruction *Loc = getInsertionPoint(LastIdx);
Builder.SetInsertPoint(Loc);
assert(getFirstUserIndex(Operands, Operands.size()) > LastIdx &&
"Vectorizing with in-tree users");
Value *Vec = vectorizeTree(Operands, Operands.size());
// After vectorizing the operands we need to generate extractelement
// instructions and replace all of the uses of the scalar values with
// the values that we extracted from the vectorized tree.
for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
Value *S = Builder.CreateExtractElement(Vec, Builder.getInt32(i));
Operands[i]->replaceAllUsesWith(S);
}
}
int BoUpSLP::getTreeCost(ArrayRef<Value *> VL) {
// Get rid of the list of stores that were removed, and from the
// lists of instructions with multiple users.
MemBarrierIgnoreList.clear();
LaneMap.clear();
MultiUserVals.clear();
MustScalarize.clear();
MustExtract.clear();
// Find the location of the last root.
int LastRootIndex = getLastIndex(VL, VL.size());
int FirstUserIndex = getFirstUserIndex(VL, VL.size());
// Don't vectorize if there are users of the tree roots inside the tree
// itself.
if (LastRootIndex > FirstUserIndex)
return max_cost;
// Scan the tree and find which value is used by which lane, and which values
// must be scalarized.
getTreeUses_rec(VL, 0);
// Check that instructions with multiple users can be vectorized. Mark unsafe
// instructions.
for (SetVector<Value*>::iterator it = MultiUserVals.begin(),
e = MultiUserVals.end(); it != e; ++it) {
// Check that all of the users of this instr are within the tree
// and that they are all from the same lane.
int Lane = -1;
for (Value::use_iterator I = (*it)->use_begin(), E = (*it)->use_end();
I != E; ++I) {
if (LaneMap.find(*I) == LaneMap.end()) {
DEBUG(dbgs()<<"SLP: Instr " << **it << " has multiple users.\n");
// We don't have an ordering problem if the user is not in this basic
// block.
Instruction *Inst = cast<Instruction>(*I);
if (Inst->getParent() != BB) {
MustExtract.insert(*it);
continue;
}
// We don't have an ordering problem if the user is after the last root.
int Idx = InstrIdx[Inst];
if (Idx < LastRootIndex) {
MustScalarize.insert(*it);
DEBUG(dbgs()<<"SLP: Adding to MustScalarize "
"because of an unsafe out of tree usage.\n");
break;
}
DEBUG(dbgs()<<"SLP: Adding to MustExtract "
"because of a safe out of tree usage.\n");
MustExtract.insert(*it);
continue;
}
if (Lane == -1) Lane = LaneMap[*I];
if (Lane != LaneMap[*I]) {
MustScalarize.insert(*it);
DEBUG(dbgs()<<"SLP: Adding " << **it <<
" to MustScalarize because multiple lane use it: "
<< Lane << " and " << LaneMap[*I] << ".\n");
break;
}
}
}
// Now calculate the cost of vectorizing the tree.
return getTreeCost_rec(VL, 0);
}
void BoUpSLP::getTreeUses_rec(ArrayRef<Value *> VL, unsigned Depth) {
if (Depth == RecursionMaxDepth) return;
// Don't handle vectors.
if (VL[0]->getType()->isVectorTy()) return;
if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
if (SI->getValueOperand()->getType()->isVectorTy()) return;
// Check if all of the operands are constants.
bool AllConst = true;
bool AllSameScalar = true;
for (unsigned i = 0, e = VL.size(); i < e; ++i) {
AllConst &= isa<Constant>(VL[i]);
AllSameScalar &= (VL[0] == VL[i]);
Instruction *I = dyn_cast<Instruction>(VL[i]);
// If one of the instructions is out of this BB, we need to scalarize all.
if (I && I->getParent() != BB) return;
}
// If all of the operands are identical or constant we have a simple solution.
if (AllConst || AllSameScalar) return;
// Scalarize unknown structures.
Instruction *VL0 = dyn_cast<Instruction>(VL[0]);
if (!VL0) return;
unsigned Opcode = VL0->getOpcode();
for (unsigned i = 0, e = VL.size(); i < e; ++i) {
Instruction *I = dyn_cast<Instruction>(VL[i]);
// If not all of the instructions are identical then we have to scalarize.
if (!I || Opcode != I->getOpcode()) return;
}
for (int i = 0, e = VL.size(); i < e; ++i) {
// Check that the instruction is only used within
// one lane.
if (LaneMap.count(VL[i]) && LaneMap[VL[i]] != i) return;
// Make this instruction as 'seen' and remember the lane.
LaneMap[VL[i]] = i;
}
// Mark instructions with multiple users.
for (unsigned i = 0, e = VL.size(); i < e; ++i) {
Instruction *I = dyn_cast<Instruction>(VL[i]);
// Remember to check if all of the users of this instr are vectorized
// within our tree. At depth zero we have no local users, only external
// users that we don't care about.
if (Depth && I && I->getNumUses() > 1) {
DEBUG(dbgs()<<"SLP: Adding to MultiUserVals "
"because it has multiple users:" << *I << " \n");
MultiUserVals.insert(I);
}
}
switch (Opcode) {
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:
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: {
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));
getTreeUses_rec(Operands, Depth+1);
}
return;
}
case Instruction::Store: {
ValueList Operands;
for (unsigned j = 0; j < VL.size(); ++j)
Operands.push_back(cast<Instruction>(VL[j])->getOperand(0));
getTreeUses_rec(Operands, Depth+1);
return;
}
default:
return;
}
}
int BoUpSLP::getTreeCost_rec(ArrayRef<Value *> VL, unsigned Depth) {
Type *ScalarTy = VL[0]->getType();
if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
ScalarTy = SI->getValueOperand()->getType();
/// Don't mess with vectors.
if (ScalarTy->isVectorTy()) return max_cost;
VectorType *VecTy = VectorType::get(ScalarTy, VL.size());
if (Depth == RecursionMaxDepth) return getScalarizationCost(VecTy);
// Check if all of the operands are constants.
bool AllConst = true;
bool AllSameScalar = true;
bool MustScalarizeFlag = false;
for (unsigned i = 0, e = VL.size(); i < e; ++i) {
AllConst &= isa<Constant>(VL[i]);
AllSameScalar &= (VL[0] == VL[i]);
// Must have a single use.
Instruction *I = dyn_cast<Instruction>(VL[i]);
MustScalarizeFlag |= MustScalarize.count(VL[i]);
// This instruction is outside the basic block.
if (I && I->getParent() != BB)
return getScalarizationCost(VecTy);
}
// Is this a simple vector constant.
if (AllConst) return 0;
// If all of the operands are identical we can broadcast them.
Instruction *VL0 = dyn_cast<Instruction>(VL[0]);
if (AllSameScalar) {
// If we are in a loop, and this is not an instruction (e.g. constant or
// argument) or the instruction is defined outside the loop then assume
// that the cost is zero.
if (L && (!VL0 || !L->contains(VL0)))
return 0;
// We need to broadcast the scalar.
return TTI->getShuffleCost(TargetTransformInfo::SK_Broadcast, VecTy, 0);
}
// If this is not a constant, or a scalar from outside the loop then we
// need to scalarize it.
if (MustScalarizeFlag)
return getScalarizationCost(VecTy);
if (!VL0) return getScalarizationCost(VecTy);
assert(VL0->getParent() == BB && "Wrong BB");
unsigned Opcode = VL0->getOpcode();
for (unsigned i = 0, e = VL.size(); i < e; ++i) {
Instruction *I = dyn_cast<Instruction>(VL[i]);
// If not all of the instructions are identical then we have to scalarize.
if (!I || Opcode != I->getOpcode()) return getScalarizationCost(VecTy);
}
// Check if it is safe to sink the loads or the stores.
if (Opcode == Instruction::Load || Opcode == Instruction::Store) {
int MaxIdx = getLastIndex(VL, VL.size());
Instruction *Last = InstrVec[MaxIdx];
for (unsigned i = 0, e = VL.size(); i < e; ++i ) {
if (VL[i] == Last) continue;
Value *Barrier = isUnsafeToSink(cast<Instruction>(VL[i]), Last);
if (Barrier) {
DEBUG(dbgs() << "SLP: Can't sink " << *VL[i] << "\n down to " <<
*Last << "\n because of " << *Barrier << "\n");
return max_cost;
}
}
}
// Calculate the extract cost.
unsigned ExternalUserExtractCost = 0;
for (unsigned i = 0, e = VL.size(); i < e; ++i)
if (MustExtract.count(VL[i]))
ExternalUserExtractCost +=
TTI->getVectorInstrCost(Instruction::ExtractElement, VecTy, i);
switch (Opcode) {
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: {
int Cost = ExternalUserExtractCost;
ValueList Operands;
Type *SrcTy = VL0->getOperand(0)->getType();
// Prepare the operand vector.
for (unsigned j = 0; j < VL.size(); ++j) {
Operands.push_back(cast<Instruction>(VL[j])->getOperand(0));
// Check that the casted type is the same for all users.
if (cast<Instruction>(VL[j])->getOperand(0)->getType() != SrcTy)
return getScalarizationCost(VecTy);
}
Cost += getTreeCost_rec(Operands, Depth+1);
if (Cost >= max_cost) return max_cost;
// 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);
Cost += (VecCost - ScalarCost);
return Cost;
}
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: {
int Cost = ExternalUserExtractCost;
// Calculate the cost of all of the operands.
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));
Cost += getTreeCost_rec(Operands, Depth+1);
if (Cost >= max_cost) return max_cost;
}
// Calculate the cost of this instruction.
int ScalarCost = VecTy->getNumElements() *
TTI->getArithmeticInstrCost(Opcode, ScalarTy);
int VecCost = TTI->getArithmeticInstrCost(Opcode, VecTy);
Cost += (VecCost - ScalarCost);
return Cost;
}
case Instruction::Load: {
// If we are scalarize the loads, add the cost of forming the vector.
for (unsigned i = 0, e = VL.size()-1; i < e; ++i)
if (!isConsecutiveAccess(VL[i], VL[i+1]))
return getScalarizationCost(VecTy);
// 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, ScalarTy, 1, 0);
return VecLdCost - ScalarLdCost + ExternalUserExtractCost;
}
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, ScalarTy, 1,0);
int StoreCost = VecStCost - ScalarStCost;
ValueList Operands;
for (unsigned j = 0; j < VL.size(); ++j) {
Operands.push_back(cast<Instruction>(VL[j])->getOperand(0));
MemBarrierIgnoreList.insert(VL[j]);
}
int TotalCost = StoreCost + getTreeCost_rec(Operands, Depth + 1);
return TotalCost + ExternalUserExtractCost;
}
default:
// Unable to vectorize unknown instructions.
return getScalarizationCost(VecTy);
}
}
int BoUpSLP::getLastIndex(ArrayRef<Value *> VL, unsigned VF) {
int MaxIdx = InstrIdx[BB->getFirstNonPHI()];
for (unsigned i = 0; i < VF; ++i )
MaxIdx = std::max(MaxIdx, InstrIdx[VL[i]]);
return MaxIdx;
}
int BoUpSLP::getFirstUserIndex(ArrayRef<Value *> VL, unsigned VF) {
// Find the first user of the values.
int FirstUser = InstrVec.size();
for (unsigned i = 0; i < VF; ++i) {
for (Value::use_iterator U = VL[i]->use_begin(), UE = VL[i]->use_end();
U != UE; ++U) {
Instruction *Instr = dyn_cast<Instruction>(*U);
if (!Instr || Instr->getParent() != BB)
continue;
FirstUser = std::min(FirstUser, InstrIdx[Instr]);
}
}
return FirstUser;
}
int BoUpSLP::getLastIndex(Instruction *I, Instruction *J) {
assert(I->getParent() == BB && "Invalid parent for instruction I");
assert(J->getParent() == BB && "Invalid parent for instruction J");
return std::max(InstrIdx[I],InstrIdx[J]);
}
Instruction *BoUpSLP::getInsertionPoint(unsigned Index) {
return InstrVec[Index + 1];
}
Value *BoUpSLP::Scalarize(ArrayRef<Value *> VL, VectorType *Ty) {
Value *Vec = UndefValue::get(Ty);
for (unsigned i=0; i < Ty->getNumElements(); ++i) {
// Generate the 'InsertElement' instruction.
Vec = Builder.CreateInsertElement(Vec, VL[i], Builder.getInt32(i));
// Remember that this instruction is used as part of a 'gather' sequence.
// The caller of the bottom-up slp vectorizer can try to hoist the sequence
// if the users are outside of the basic block.
GatherInstructions.push_back(Vec);
}
for (unsigned i = 0; i < Ty->getNumElements(); ++i)
VectorizedValues[VL[i]] = Vec;
return Vec;
}
Value *BoUpSLP::vectorizeTree(ArrayRef<Value *> VL, int VF) {
Value *V = vectorizeTree_rec(VL, VF);
int LastInstrIdx = getLastIndex(VL, VL.size());
for (SetVector<Value*>::iterator it = MustExtract.begin(),
e = MustExtract.end(); it != e; ++it) {
Instruction *I = cast<Instruction>(*it);
// This is a scalarized value, so we can use the original value.
// No need to extract from the vector.
if (!LaneMap.count(I))
continue;
Value *Vec = VectorizedValues[I];
// We decided not to vectorize I because one of its users was not
// vectorizerd. This is okay.
if (!Vec)
continue;
Value *Idx = Builder.getInt32(LaneMap[I]);
Value *Extract = Builder.CreateExtractElement(Vec, Idx);
bool Replaced = false;
for (Value::use_iterator U = I->use_begin(), UE = I->use_end(); U != UE;
++U) {
Instruction *UI = cast<Instruction>(*U);
if (UI->getParent() != I->getParent() || InstrIdx[UI] > LastInstrIdx)
UI->replaceUsesOfWith(I ,Extract);
Replaced = true;
}
assert(Replaced && "Must replace at least one outside user");
(void)Replaced;
}
// We moved some instructions around. We have to number them again
// before we can do any analysis.
numberInstructions();
MustScalarize.clear();
MustExtract.clear();
VectorizedValues.clear();
return V;
}
Value *BoUpSLP::vectorizeTree_rec(ArrayRef<Value *> VL, int VF) {
Type *ScalarTy = VL[0]->getType();
if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
ScalarTy = SI->getValueOperand()->getType();
VectorType *VecTy = VectorType::get(ScalarTy, VF);
// Check if all of the operands are constants or identical.
bool AllConst = true;
bool AllSameScalar = true;
for (unsigned i = 0, e = VF; i < e; ++i) {
AllConst &= isa<Constant>(VL[i]);
AllSameScalar &= (VL[0] == VL[i]);
// The instruction must be in the same BB, and it must be vectorizable.
Instruction *I = dyn_cast<Instruction>(VL[i]);
if (MustScalarize.count(VL[i]) || (I && I->getParent() != BB))
return Scalarize(VL, VecTy);
}
// Check that this is a simple vector constant.
if (AllConst || AllSameScalar)
return Scalarize(VL, VecTy);
// Scalarize unknown structures.
Instruction *VL0 = dyn_cast<Instruction>(VL[0]);
if (!VL0)
return Scalarize(VL, VecTy);
if (VectorizedValues.count(VL0)) {
Value * Vec = VectorizedValues[VL0];
for (int i = 0; i < VF; ++i)
VectorizedValues[VL[i]] = Vec;
return Vec;
}
unsigned Opcode = VL0->getOpcode();
for (unsigned i = 0, e = VF; i < e; ++i) {
Instruction *I = dyn_cast<Instruction>(VL[i]);
// If not all of the instructions are identical then we have to scalarize.
if (!I || Opcode != I->getOpcode())
return Scalarize(VL, VecTy);
}
switch (Opcode) {
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; i < VF; ++i)
INVL.push_back(cast<Instruction>(VL[i])->getOperand(0));
Value *InVec = vectorizeTree_rec(INVL, VF);
CastInst *CI = dyn_cast<CastInst>(VL0);
Value *V = Builder.CreateCast(CI->getOpcode(), InVec, VecTy);
for (int i = 0; i < VF; ++i)
VectorizedValues[VL[i]] = 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;
for (int i = 0; i < VF; ++i) {
LHSVL.push_back(cast<Instruction>(VL[i])->getOperand(0));
RHSVL.push_back(cast<Instruction>(VL[i])->getOperand(1));
}
Value *LHS = vectorizeTree_rec(LHSVL, VF);
Value *RHS = vectorizeTree_rec(RHSVL, VF);
BinaryOperator *BinOp = cast<BinaryOperator>(VL0);
Value *V = Builder.CreateBinOp(BinOp->getOpcode(), LHS,RHS);
for (int i = 0; i < VF; ++i)
VectorizedValues[VL[i]] = V;
return V;
}
case Instruction::Load: {
LoadInst *LI = cast<LoadInst>(VL0);
unsigned Alignment = LI->getAlignment();
// Check if all of the loads are consecutive.
for (unsigned i = 1, e = VF; i < e; ++i)
if (!isConsecutiveAccess(VL[i-1], VL[i]))
return Scalarize(VL, VecTy);
// Loads are inserted at the head of the tree because we don't want to sink
// them all the way down past store instructions.
Instruction *Loc = getInsertionPoint(getLastIndex(VL, VL.size()));
IRBuilder<> LoadBuilder(Loc);
Value *VecPtr = LoadBuilder.CreateBitCast(LI->getPointerOperand(),
VecTy->getPointerTo());
LI = LoadBuilder.CreateLoad(VecPtr);
LI->setAlignment(Alignment);
for (int i = 0; i < VF; ++i)
VectorizedValues[VL[i]] = LI;
return LI;
}
case Instruction::Store: {
StoreInst *SI = cast<StoreInst>(VL0);
unsigned Alignment = SI->getAlignment();
ValueList ValueOp;
for (int i = 0; i < VF; ++i)
ValueOp.push_back(cast<StoreInst>(VL[i])->getValueOperand());
Value *VecValue = vectorizeTree_rec(ValueOp, VF);
Value *VecPtr = Builder.CreateBitCast(SI->getPointerOperand(),
VecTy->getPointerTo());
Builder.CreateStore(VecValue, VecPtr)->setAlignment(Alignment);
for (int i = 0; i < VF; ++i)
cast<Instruction>(VL[i])->eraseFromParent();
return 0;
}
default:
return Scalarize(VL, VecTy);
}
}
} // end of namespace
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