/*===================== begin_copyright_notice ==================================

Copyright (c) 2017 Intel Corporation

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======================= end_copyright_notice ==================================*/

#include "Compiler/CodeGenContextWrapper.hpp"
#include "Compiler/MetaDataUtilsWrapper.h"
#include "Compiler/CISACodeGen/RegisterPressureEstimate.hpp"
#include "Compiler/CISACodeGen/WIAnalysis.hpp"
#include "common/LLVMUtils.h"

#include "Compiler/CISACodeGen/LowerGEPForPrivMem.hpp"
#include "Compiler/CodeGenPublic.h"
#include "Compiler/IGCPassSupport.h"
#include "Compiler/CISACodeGen/ShaderCodeGen.hpp"
#include "common/LLVMWarningsPush.hpp"

#include "llvmWrapper/IR/IRBuilder.h"

#include <llvm/IR/Function.h>
#include <llvm/IR/Instructions.h>
#include <llvm/ADT/SmallVector.h>
#include "common/LLVMWarningsPop.hpp"

#define MAX_ALLOCA_PROMOTE_GRF_NUM      48
#define MAX_PRESSURE_GRF_NUM            64

using namespace llvm;
using namespace IGC;
using namespace IGC::IGCMD;

namespace IGC {
/// @brief  LowerGEPForPrivMem pass is used for lowering the allocas identified while visiting the alloca instructions
///         and then inserting insert/extract elements instead of load stores. This allows us
///         to store the data in registers instead of propagating it to scratch space.
class LowerGEPForPrivMem : public llvm::FunctionPass, public llvm::InstVisitor<LowerGEPForPrivMem>
{
public:
    LowerGEPForPrivMem();

    ~LowerGEPForPrivMem() {}

    virtual llvm::StringRef getPassName() const override
    {
        return "LowerGEPForPrivMem";
    }

    virtual void getAnalysisUsage(llvm::AnalysisUsage &AU) const override
    {
        AU.addRequired<RegisterPressureEstimate>();
        AU.addRequired<MetaDataUtilsWrapper>();
        AU.addRequired<CodeGenContextWrapper>();
        AU.addRequired<WIAnalysis>();
        AU.setPreservesCFG();
    }

    virtual bool runOnFunction(llvm::Function &F) override;

    void visitAllocaInst(llvm::AllocaInst &I);

    unsigned int extractAllocaSize(llvm::AllocaInst* pAlloca);

private:
    llvm::AllocaInst* createVectorForAlloca(
        llvm::AllocaInst *pAlloca,
        llvm::Type *pBaseType);
    void handleAllocaInst(llvm::AllocaInst *pAlloca);

    bool CheckIfAllocaPromotable(llvm::AllocaInst* pAlloca);
    bool IsNativeType(Type* type);
    /// Conservatively check if a store allow an Alloca to be uniform
    bool IsUniformStore(llvm::StoreInst* pStore);
public:
    static char ID;

private:
    const llvm::DataLayout                              *m_pDL;
    CodeGenContext                                      *m_ctx;
    std::vector<llvm::AllocaInst*>                       m_allocasToPrivMem;
    RegisterPressureEstimate*                            m_pRegisterPressureEstimate;
    llvm::Function                                      *m_pFunc;

    /// Keep track of each BB affected by promoting MemtoReg and the current pressure at that block
    llvm::DenseMap<llvm::BasicBlock *, unsigned>         m_pBBPressure;

    struct PromotedLiverange
    {
        unsigned int lowId;
        unsigned int highId;
        unsigned int varSize;
    };

    std::vector<PromotedLiverange> m_promotedLiveranges;
};

FunctionPass *createPromotePrivateArrayToReg()
{
    return new LowerGEPForPrivMem();
}
}

// Register pass to igc-opt
#define PASS_FLAG "igc-priv-mem-to-reg"
#define PASS_DESCRIPTION "Lower GEP of Private Memory to Register Pass"
#define PASS_CFG_ONLY false
#define PASS_ANALYSIS false
IGC_INITIALIZE_PASS_BEGIN(LowerGEPForPrivMem, PASS_FLAG, PASS_DESCRIPTION, PASS_CFG_ONLY, PASS_ANALYSIS)
IGC_INITIALIZE_PASS_DEPENDENCY(RegisterPressureEstimate)
IGC_INITIALIZE_PASS_DEPENDENCY(MetaDataUtilsWrapper)
IGC_INITIALIZE_PASS_DEPENDENCY(CodeGenContextWrapper)
IGC_INITIALIZE_PASS_END(LowerGEPForPrivMem, PASS_FLAG, PASS_DESCRIPTION, PASS_CFG_ONLY, PASS_ANALYSIS)

char LowerGEPForPrivMem::ID = 0;

LowerGEPForPrivMem::LowerGEPForPrivMem() : FunctionPass(ID), m_pFunc(nullptr)
{
    initializeLowerGEPForPrivMemPass(*PassRegistry::getPassRegistry());
}

llvm::AllocaInst* LowerGEPForPrivMem::createVectorForAlloca(
    llvm::AllocaInst* pAlloca,
    llvm::Type* pBaseType)
{
    IGCLLVM::IRBuilder<> IRB(pAlloca);

    unsigned int totalSize = extractAllocaSize(pAlloca) / int_cast<unsigned int>(m_pDL->getTypeAllocSize(pBaseType));

    llvm::VectorType* pVecType = llvm::VectorType::get(pBaseType, totalSize);

    AllocaInst *pAllocaValue = IRB.CreateAlloca(pVecType);
    return pAllocaValue;
}

bool LowerGEPForPrivMem::runOnFunction(llvm::Function &F)
{
    m_pFunc = &F;
    CodeGenContextWrapper* pCtxWrapper = &getAnalysis<CodeGenContextWrapper>();
    m_ctx = pCtxWrapper->getCodeGenContext();

    MetaDataUtils *pMdUtils = getAnalysis<MetaDataUtilsWrapper>().getMetaDataUtils();
    if (pMdUtils->findFunctionsInfoItem(&F) == pMdUtils->end_FunctionsInfo())
    {
        return false;
    }
    m_pDL = &F.getParent()->getDataLayout();
    m_pRegisterPressureEstimate = &getAnalysis<RegisterPressureEstimate>();
    m_pRegisterPressureEstimate->buildRPMapPerInstruction();
    m_allocasToPrivMem.clear();

    visit(F);

    std::vector<llvm::AllocaInst*> &allocaToHande = m_allocasToPrivMem;
    for (auto pAlloca : allocaToHande)
    {
        handleAllocaInst(pAlloca);
    }

    // Last remove alloca instructions
    for (auto pInst : allocaToHande)
    {
        if (pInst->use_empty())
        {
            pInst->eraseFromParent();
        }
    }

    if (!allocaToHande.empty())
        DumpLLVMIR(m_ctx, "AfterLowerGEP");
    // IR changed only if we had alloca instruction to optimize
    return !allocaToHande.empty();
}

void TransposeHelper::EraseDeadCode()
{
    for(auto pInst = m_toBeRemovedGEP.rbegin(); pInst != m_toBeRemovedGEP.rend(); ++pInst)
    {
        assert((*pInst)->use_empty() && "Instruction still has usage");
        (*pInst)->eraseFromParent();
    }
}

unsigned int LowerGEPForPrivMem::extractAllocaSize(llvm::AllocaInst* pAlloca)
{
    unsigned int arraySize = int_cast<unsigned int>(cast<ConstantInt>(pAlloca->getArraySize())->getZExtValue());
    unsigned int totalArrayStructureSize = int_cast<unsigned int>(m_pDL->getTypeAllocSize(pAlloca->getAllocatedType()) * arraySize);

    return totalArrayStructureSize;
}

static void GetAllocaLiverange(Instruction* I, unsigned int& liverangeStart, unsigned int& liverangeEnd, RegisterPressureEstimate* rpe)
{
    for(Value::user_iterator use_it = I->user_begin(), use_e = I->user_end(); use_it != use_e; ++use_it)
    {
        if(isa<GetElementPtrInst>(*use_it) || isa<BitCastInst>(*use_it))
        {
            GetAllocaLiverange(cast<Instruction>(*use_it), liverangeStart, liverangeEnd, rpe);
        }
        else if(isa<LoadInst>(*use_it) || isa<StoreInst>(*use_it) || isa<llvm::IntrinsicInst>(*use_it))
        {
            unsigned int idx = rpe->getAssignedNumberForInst(cast<Instruction>(*use_it));
            liverangeStart = std::min(liverangeStart, idx);
            liverangeEnd = std::max(liverangeEnd, idx);
        }
    }
}

bool LowerGEPForPrivMem::IsNativeType(Type* type)
{
    if((type->isDoubleTy() && !m_ctx->platform.supportFP64()) ||
        (type->isIntegerTy(64) && m_ctx->platform.hasNo64BitInst()))
    {
        return false;
    }
    return true;
}

bool LowerGEPForPrivMem::CheckIfAllocaPromotable(llvm::AllocaInst* pAlloca)
{
    auto WI = &getAnalysis<WIAnalysis>();
    bool isUniformAlloca = WI->whichDepend(pAlloca) == WIAnalysis::UNIFORM;
    if(isUniformAlloca)
    {
        IRBuilder<> builder(pAlloca);
        MDNode* node = MDNode::get(pAlloca->getContext(), ConstantAsMetadata::get(builder.getInt1(true)));
        pAlloca->setMetadata("uniform", node);
    }
    unsigned int allocaSize = extractAllocaSize(pAlloca);
    unsigned int allowedAllocaSizeInBytes = MAX_ALLOCA_PROMOTE_GRF_NUM * 4;

    // scale alloc size based on the number of GRFs we have
    float grfRatio = m_ctx->getNumGRFPerThread() / 128.0f;
    allowedAllocaSizeInBytes = (uint32_t) (allowedAllocaSizeInBytes * grfRatio);

    if (m_ctx->type == ShaderType::COMPUTE_SHADER)
    {
        ComputeShaderContext* ctx = static_cast<ComputeShaderContext*>(m_ctx);
        SIMDMode simdMode = ctx->GetLeastSIMDModeAllowed();
        unsigned d = simdMode == SIMDMode::SIMD32 ? 4 : 1;

        allowedAllocaSizeInBytes = allowedAllocaSizeInBytes / d;
    }
    Type* baseType = nullptr;
    if(!CanUseSOALayout(pAlloca, baseType))
    {
        return false;
    }
    if(!IsNativeType(baseType))
    {
        return false;
    }
    if(isUniformAlloca)
    {
        // Heuristic: for uniform alloca we divide the size by 8 to adjust the pressure
        // as they will be allocated as uniform array
        allocaSize = iSTD::Round(allocaSize, 8) / 8;
    }

    if(allocaSize <= IGC_GET_FLAG_VALUE(ByPassAllocaSizeHeuristic))
    {
        return true;
    }

    // if alloca size exceeds alloc size threshold, return false
    if (allocaSize > allowedAllocaSizeInBytes)
    {
        return false;
    }
    // if no live range info
    if (!m_pRegisterPressureEstimate->isAvailable())
    {
        return true;
    }

    // get all the basic blocks that contain the uses of the alloca
    // then estimate how much changing this alloca to register adds to the pressure at that block.
    unsigned int lowestAssignedNumber = 0xFFFFFFFF;
    unsigned int highestAssignedNumber = 0;

    GetAllocaLiverange(pAlloca, lowestAssignedNumber, highestAssignedNumber, m_pRegisterPressureEstimate);
    
    uint32_t maxGRFPressure = (uint32_t)(grfRatio * MAX_PRESSURE_GRF_NUM * 4);

    unsigned int pressure = 0;
    for(unsigned int i = lowestAssignedNumber; i <= highestAssignedNumber; i++)
    {
        pressure = std::max(
            pressure, m_pRegisterPressureEstimate->getRegisterPressureForInstructionFromRPMap(i));
    }

    for(auto it : m_promotedLiveranges)
    {
        // check interval intersection
        if((it.lowId < lowestAssignedNumber && it.highId > lowestAssignedNumber) ||
            (it.lowId > lowestAssignedNumber && it.lowId < highestAssignedNumber))
        {
            pressure += it.varSize;
        }
    }

    if(allocaSize + pressure > maxGRFPressure)
    {
        return false;
    }
    PromotedLiverange liverange;
    liverange.lowId = lowestAssignedNumber;
    liverange.highId = highestAssignedNumber;
    liverange.varSize = allocaSize;
    m_promotedLiveranges.push_back(liverange);
    return true;
}

static Type* GetBaseType(Type* pType)
{
    if(pType->isStructTy())
    {
        int num_elements = pType->getStructNumElements();
        if(num_elements != 1)
            return nullptr;

        pType = pType->getStructElementType(0);
    }

    while(pType->isArrayTy())
    {
        pType = pType->getArrayElementType();
    }

    if(pType->isStructTy())
    {
        int num_elements = pType->getStructNumElements();
        if(num_elements != 1)
            return nullptr;

        pType = pType->getStructElementType(0);
    }
    return pType;
}

static bool CheckUsesForSOAAlyout(Instruction* I, bool& vectorSOA)
{
    for(Value::user_iterator use_it = I->user_begin(), use_e = I->user_end(); use_it != use_e; ++use_it)
    {
        if(GetElementPtrInst* gep = dyn_cast<GetElementPtrInst>(*use_it))
        {
            if(CheckUsesForSOAAlyout(gep, vectorSOA))
                continue;
        }
        if(llvm::LoadInst* pLoad = llvm::dyn_cast<llvm::LoadInst>(*use_it))
        {
            vectorSOA &= pLoad->getType()->isVectorTy();
            if(!pLoad->isSimple())
                return false;
        }
        else if(llvm::StoreInst* pStore = llvm::dyn_cast<llvm::StoreInst>(*use_it))
        {
            if(!pStore->isSimple())
                return false;
            llvm::Value* pValueOp = pStore->getValueOperand();
            vectorSOA &= pStore->getValueOperand()->getType()->isVectorTy();
            if(pValueOp == I)
            {
                // GEP instruction is the stored value of the StoreInst (not supported case)
                return false;
            }
        }
        else if(llvm::BitCastInst *pBitCast = llvm::dyn_cast<llvm::BitCastInst>(*use_it))
        {
            Type* baseT = GetBaseType(pBitCast->getType()->getPointerElementType());
            Type* sourceType = GetBaseType(pBitCast->getOperand(0)->getType()->getPointerElementType());
            if(pBitCast->use_empty())
            {
                continue;
            }
            else if(baseT != nullptr &&
                baseT->getScalarSizeInBits() != 0 &&
                baseT->getScalarSizeInBits() == sourceType->getScalarSizeInBits())
            {
                vectorSOA &= baseT->getPrimitiveSizeInBits() == sourceType->getPrimitiveSizeInBits();
                if(CheckUsesForSOAAlyout(pBitCast, vectorSOA))
                    continue;
            }
            else if(IsBitCastForLifetimeMark(pBitCast))
            {
                continue;
            }
            // Not a candidate.
            return false;
        }
        else if(IntrinsicInst* intr = dyn_cast<IntrinsicInst>(*use_it))
        {
            llvm::Intrinsic::ID  IID = intr->getIntrinsicID();
            if(IID == llvm::Intrinsic::lifetime_start ||
                IID == llvm::Intrinsic::lifetime_end)
            {
                continue;
            }
            return false;
        }
        else
        {
            // This is some other instruction. Right now we don't want to handle these
            return false;
        }
    }
    return true;
}


bool IGC::CanUseSOALayout(AllocaInst* I, Type*& base)
{
    // Don't even look at non-array allocas.
    // (extractAllocaDim can not handle them anyway, causing a crash)
    llvm::Type* pType = I->getType()->getPointerElementType();
    if(pType->isStructTy() && pType->getStructNumElements() == 1)
    {
        pType = pType->getStructElementType(0);
    }
    if((!pType->isArrayTy() && !pType->isVectorTy()) || I->isArrayAllocation())
        return false;

    base = GetBaseType(pType);
    if(base == nullptr)
        return false;
    // only handle case with a simple base type
    if(!(base->getScalarType()->isFloatingPointTy() || base->getScalarType()->isIntegerTy()))
        return false;
    bool vectorSOA = true;
    bool useSOA = CheckUsesForSOAAlyout(I, vectorSOA);
    if(!vectorSOA)
    {
        base = base->getScalarType();
    }
    return useSOA;
}

void LowerGEPForPrivMem::visitAllocaInst(AllocaInst &I)
{
    // Alloca should always be private memory
    assert(I.getType()->getAddressSpace() == ADDRESS_SPACE_PRIVATE);
    if (!CheckIfAllocaPromotable(&I))
    {
        // alloca size extends remain per-lane-reg space
        return;
    }
    m_allocasToPrivMem.push_back(&I);
}

void TransposeHelper::HandleAllocaSources(Instruction* v, Value* idx)
{
    SmallVector<Value*, 10> instructions;
    for(Value::user_iterator it = v->user_begin(), e = v->user_end(); it != e; ++it)
    {
        Value* inst = cast<Value>(*it);
        instructions.push_back(inst);
    }
    
    for(auto instruction : instructions)
    {
        if(GetElementPtrInst *pGEP = dyn_cast<GetElementPtrInst>(instruction))
        {
            handleGEPInst(pGEP, idx);
        }
        else if(BitCastInst* bitcast = dyn_cast<BitCastInst>(instruction))
        {
            m_toBeRemovedGEP.push_back(bitcast);
            HandleAllocaSources(bitcast, idx);
        }
        else if(StoreInst *pStore = llvm::dyn_cast<StoreInst>(instruction))
        {
            handleStoreInst(pStore, idx);
        }
        else if(LoadInst *pLoad = llvm::dyn_cast<LoadInst>(instruction))
        {
            handleLoadInst(pLoad, idx);
        }
        else if(IntrinsicInst* inst = dyn_cast<IntrinsicInst>(instruction))
        {
            handleLifetimeMark(inst);
        }
    }
}

class TransposeHelperPromote : public TransposeHelper
{
public:
    void handleLoadInst(
        LoadInst *pLoad,
        Value *pScalarizedIdx);
    void handleStoreInst(
        StoreInst *pStore,
        Value *pScalarizedIdx);
    AllocaInst *pVecAlloca;
    TransposeHelperPromote(AllocaInst* pAI) : TransposeHelper(false) { pVecAlloca = pAI; }
};

void LowerGEPForPrivMem::handleAllocaInst(llvm::AllocaInst* pAlloca)
{
    // Extract the Alloca size and the base Type
    Type* pType = pAlloca->getType()->getPointerElementType();
    Type* pBaseType = GetBaseType(pType)->getScalarType();
	assert(pBaseType);
    llvm::AllocaInst* pVecAlloca = createVectorForAlloca(pAlloca, pBaseType);
    if (!pVecAlloca)
    {
        return;
    }
    
    IRBuilder<> IRB(pVecAlloca);
    Value* idx = IRB.getInt32(0);
    TransposeHelperPromote helper(pVecAlloca);
    helper.HandleAllocaSources(pAlloca, idx);
    helper.EraseDeadCode();
}

void TransposeHelper::handleLifetimeMark(IntrinsicInst *inst)
{
    assert(inst->getIntrinsicID() == llvm::Intrinsic::lifetime_start ||
        inst->getIntrinsicID() == llvm::Intrinsic::lifetime_end);
    inst->eraseFromParent();
}

void TransposeHelper::handleGEPInst(
    llvm::GetElementPtrInst *pGEP,
    llvm::Value* idx)
{
    assert(static_cast<ADDRESS_SPACE>(pGEP->getPointerAddressSpace()) == ADDRESS_SPACE_PRIVATE);
    // Add GEP instruction to remove list
    m_toBeRemovedGEP.push_back(pGEP);
    if (pGEP->use_empty())
    {
        // GEP has no users, do nothing.
        return;
    }

    // Given %p = getelementptr [4 x [3 x <2 x float>]]* %v, i64 0, i64 %1, i64 %2
    // compute the scalarized index with an auxiliary array [4, 3, 2]:
    //
    // Formula: index = (%1 x 3 + %2) x 2
    //
    IRBuilder<> IRB(pGEP);
    Value *pScalarizedIdx = IRB.getInt32(0);
    Type* T = pGEP->getPointerOperandType()->getPointerElementType();
    for (unsigned i = 0, e = pGEP->getNumIndices(); i < e; ++i)
    {
        auto GepOpnd = IRB.CreateZExtOrTrunc(pGEP->getOperand(i + 1), IRB.getInt32Ty());
        unsigned int arr_sz = 1;
        if(T->isStructTy())
        {
            arr_sz = 1;
            T = T->getStructElementType(0);
        }
        else if(T->isArrayTy())
        {
            arr_sz = int_cast<unsigned int>(T->getArrayNumElements());
            T = T->getArrayElementType();
        }
        else if(T->isVectorTy())
        {
            // based on whether we want the index in number of element or number of vector
            if(m_vectorIndex)
            {
                arr_sz = 1;
            }
            else
            {
                arr_sz = T->getVectorNumElements();
            }
            T = T->getVectorElementType();
        }

        pScalarizedIdx = IRB.CreateNUWAdd(pScalarizedIdx, GepOpnd);
        pScalarizedIdx = IRB.CreateNUWMul(pScalarizedIdx, IRB.getInt32(arr_sz));
    }
    pScalarizedIdx = IRB.CreateNUWAdd(pScalarizedIdx, idx);
    HandleAllocaSources(pGEP, pScalarizedIdx);
}

// Load N elements from a vector alloca, Idx, ... Idx + N - 1. Return a scalar
// or a vector value depending on N.
static Value *loadEltsFromVecAlloca(
    unsigned N, AllocaInst *pVecAlloca,
    Value *pScalarizedIdx, 
    IRBuilder<> &IRB,
    Type* scalarType)
{
    Value *pLoadVecAlloca = IRB.CreateLoad(pVecAlloca);
    if (N == 1)
    {
        return IRB.CreateBitCast(
            IRB.CreateExtractElement(pLoadVecAlloca, pScalarizedIdx),
            scalarType);
    }

    // A vector load
    // %v = load <2 x float>* %ptr
    // becomes
    // %w = load <32 x float>* %ptr1
    // %v0 = extractelement <32 x float> %w, i32 %idx
    // %v1 = extractelement <32 x float> %w, i32 %idx+1
    // replace all uses of %v with <%v0, %v1>
    assert(N > 1 && "out of sync");
    Type* Ty = VectorType::get(scalarType, N);
    Value *Result = UndefValue::get(Ty);

    for(unsigned i = 0; i < N; ++i)
    {
        Value *VectorIdx = ConstantInt::get(pScalarizedIdx->getType(), i);
        auto Idx = IRB.CreateAdd(pScalarizedIdx, VectorIdx);
        auto Val = IRB.CreateExtractElement(pLoadVecAlloca, Idx);
        Val = IRB.CreateBitCast(Val, scalarType);
        Result = IRB.CreateInsertElement(Result, Val, VectorIdx);
    }
    return Result;
}

void TransposeHelperPromote::handleLoadInst(
    LoadInst *pLoad,
    Value *pScalarizedIdx)
{
    assert(pLoad->isSimple());
    IRBuilder<> IRB(pLoad);
    unsigned N = pLoad->getType()->isVectorTy()
                     ? pLoad->getType()->getVectorNumElements()
                     : 1;
    Value *Val = loadEltsFromVecAlloca(N, pVecAlloca, pScalarizedIdx, IRB, pLoad->getType()->getScalarType());
    pLoad->replaceAllUsesWith(Val);
    pLoad->eraseFromParent();
}

void TransposeHelperPromote::handleStoreInst(
    llvm::StoreInst *pStore,
    llvm::Value *pScalarizedIdx)
{
    // Add Store instruction to remove list
    assert(pStore->isSimple());

    IRBuilder<> IRB(pStore);
    llvm::Value* pStoreVal = pStore->getValueOperand();
    llvm::Value* pLoadVecAlloca = IRB.CreateLoad(pVecAlloca);
    llvm::Value* pIns = pLoadVecAlloca;
    if (pStoreVal->getType()->isVectorTy())
    {
        // A vector store
        // store <2 x float> %v, <2 x float>* %ptr
        // becomes
        // %w = load <32 x float> *%ptr1
        // %v0 = extractelement <2 x float> %v, i32 0
        // %w0 = insertelement <32 x float> %w, float %v0, i32 %idx
        // %v1 = extractelement <2 x float> %v, i32 1
        // %w1 = insertelement <32 x float> %w0, float %v1, i32 %idx+1
        // store <32 x float> %w1, <32 x float>* %ptr1
        for (unsigned i = 0, e = pStoreVal->getType()->getVectorNumElements(); i < e; ++i)
        {
            Value *VectorIdx = ConstantInt::get(pScalarizedIdx->getType(), i);
            auto Val = IRB.CreateExtractElement(pStoreVal, VectorIdx);
            Val = IRB.CreateBitCast(Val, pLoadVecAlloca->getType()->getScalarType());
            auto Idx = IRB.CreateAdd(pScalarizedIdx, VectorIdx);
            pIns = IRB.CreateInsertElement(pIns, Val, Idx);
        }
    }
    else
    {
        pStoreVal = IRB.CreateBitCast(pStoreVal, pLoadVecAlloca->getType()->getScalarType());
        pIns = IRB.CreateInsertElement(pLoadVecAlloca, pStoreVal, pScalarizedIdx);
    }
    IRB.CreateStore(pIns, pVecAlloca);
    pStore->eraseFromParent();
}
