C++ Use::IsInitialized方法代码示例

void Rationalizer::RewriteAssignment(LIR::Use& use)
{
    assert(use.IsInitialized());

    GenTreeOp* assignment = use.Def()->AsOp();
    assert(assignment->OperGet() == GT_ASG);

    GenTree* location = assignment->gtGetOp1();
    GenTree* value    = assignment->gtGetOp2();

    genTreeOps locationOp = location->OperGet();
    switch (locationOp)
    {
        case GT_LCL_VAR:
        case GT_LCL_FLD:
        case GT_REG_VAR:
        case GT_PHI_ARG:
            RewriteAssignmentIntoStoreLclCore(assignment, location, value, locationOp);
            BlockRange().Remove(location);
            break;

        case GT_IND:
        {
            GenTreeStoreInd* store =
                new (comp, GT_STOREIND) GenTreeStoreInd(location->TypeGet(), location->gtGetOp1(), value);

            copyFlags(store, assignment, GTF_ALL_EFFECT);
            copyFlags(store, location, GTF_IND_FLAGS);

            if (assignment->IsReverseOp())
            {
                store->gtFlags |= GTF_REVERSE_OPS;
            }

            // TODO: JIT dump

            // Remove the GT_IND node and replace the assignment node with the store
            BlockRange().Remove(location);
            BlockRange().InsertBefore(assignment, store);
            use.ReplaceWith(comp, store);
            BlockRange().Remove(assignment);
        }
        break;

        case GT_CLS_VAR:
        {
            location->SetOper(GT_CLS_VAR_ADDR);
            location->gtType = TYP_BYREF;

            assignment->SetOper(GT_STOREIND);

            // TODO: JIT dump
        }
        break;

        default:
            unreached();
            break;
    }
}

void Rationalizer::RewriteAddress(LIR::Use& use)
{
    assert(use.IsInitialized());

    GenTreeUnOp* address = use.Def()->AsUnOp();
    assert(address->OperGet() == GT_ADDR);

    GenTree*   location   = address->gtGetOp1();
    genTreeOps locationOp = location->OperGet();

    if (location->IsLocal())
    {
// We are changing the child from GT_LCL_VAR TO GT_LCL_VAR_ADDR.
// Therefore gtType of the child needs to be changed to a TYP_BYREF
#ifdef DEBUG
        if (locationOp == GT_LCL_VAR)
        {
            JITDUMP("Rewriting GT_ADDR(GT_LCL_VAR) to GT_LCL_VAR_ADDR:\n");
        }
        else
        {
            assert(locationOp == GT_LCL_FLD);
            JITDUMP("Rewriting GT_ADDR(GT_LCL_FLD) to GT_LCL_FLD_ADDR:\n");
        }
#endif // DEBUG

        location->SetOper(addrForm(locationOp));
        location->gtType = TYP_BYREF;
        copyFlags(location, address, GTF_ALL_EFFECT);

        use.ReplaceWith(comp, location);
        BlockRange().Remove(address);
    }
    else if (locationOp == GT_CLS_VAR)
    {
        location->SetOper(GT_CLS_VAR_ADDR);
        location->gtType = TYP_BYREF;
        copyFlags(location, address, GTF_ALL_EFFECT);

        use.ReplaceWith(comp, location);
        BlockRange().Remove(address);

        JITDUMP("Rewriting GT_ADDR(GT_CLS_VAR) to GT_CLS_VAR_ADDR:\n");
    }
    else if (location->OperIsIndir())
    {
        use.ReplaceWith(comp, location->gtGetOp1());
        BlockRange().Remove(location);
        BlockRange().Remove(address);

        JITDUMP("Rewriting GT_ADDR(GT_IND(X)) to X:\n");
    }

    DISPTREERANGE(BlockRange(), use.Def());
    JITDUMP("\n");
}

void Rationalizer::RewriteAssignment(LIR::Use& use)
{
    assert(use.IsInitialized());

    GenTreeOp* assignment = use.Def()->AsOp();
    assert(assignment->OperGet() == GT_ASG);

    GenTree* location = assignment->gtGetOp1();
    GenTree* value    = assignment->gtGetOp2();

    genTreeOps locationOp = location->OperGet();

    if (assignment->OperIsBlkOp())
    {
#ifdef FEATURE_SIMD
        if (varTypeIsSIMD(location) && assignment->OperIsInitBlkOp())
        {
            if (location->OperGet() == GT_LCL_VAR)
            {
                var_types simdType = location->TypeGet();
                GenTree*  initVal  = assignment->gtOp.gtOp2;
                var_types baseType = comp->getBaseTypeOfSIMDLocal(location);
                if (baseType != TYP_UNKNOWN)
                {
                    GenTreeSIMD* simdTree = new (comp, GT_SIMD)
                        GenTreeSIMD(simdType, initVal, SIMDIntrinsicInit, baseType, genTypeSize(simdType));
                    assignment->gtOp.gtOp2 = simdTree;
                    value                  = simdTree;
                    initVal->gtNext        = simdTree;
                    simdTree->gtPrev       = initVal;

                    simdTree->gtNext = location;
                    location->gtPrev = simdTree;
                }
            }
        }
#endif // FEATURE_SIMD
        if ((location->TypeGet() == TYP_STRUCT) && !assignment->IsPhiDefn() && !value->IsMultiRegCall())
        {
            if ((location->OperGet() == GT_LCL_VAR))
            {
                // We need to construct a block node for the location.
                // Modify lcl to be the address form.
                location->SetOper(addrForm(locationOp));
                LclVarDsc* varDsc     = &(comp->lvaTable[location->AsLclVarCommon()->gtLclNum]);
                location->gtType      = TYP_BYREF;
                GenTreeBlk*  storeBlk = nullptr;
                unsigned int size     = varDsc->lvExactSize;

                if (varDsc->lvStructGcCount != 0)
                {
                    CORINFO_CLASS_HANDLE structHnd = varDsc->lvVerTypeInfo.GetClassHandle();
                    GenTreeObj*          objNode   = comp->gtNewObjNode(structHnd, location)->AsObj();
                    unsigned int         slots = (unsigned)(roundUp(size, TARGET_POINTER_SIZE) / TARGET_POINTER_SIZE);

                    objNode->SetGCInfo(varDsc->lvGcLayout, varDsc->lvStructGcCount, slots);
                    objNode->ChangeOper(GT_STORE_OBJ);
                    objNode->SetData(value);
                    comp->fgMorphUnsafeBlk(objNode);
                    storeBlk = objNode;
                }
                else
                {
                    storeBlk = new (comp, GT_STORE_BLK) GenTreeBlk(GT_STORE_BLK, TYP_STRUCT, location, value, size);
                }
                storeBlk->gtFlags |= (GTF_REVERSE_OPS | GTF_ASG);
                storeBlk->gtFlags |= ((location->gtFlags | value->gtFlags) & GTF_ALL_EFFECT);

                GenTree* insertionPoint = location->gtNext;
                BlockRange().InsertBefore(insertionPoint, storeBlk);
                use.ReplaceWith(comp, storeBlk);
                BlockRange().Remove(assignment);
                JITDUMP("After transforming local struct assignment into a block op:\n");
                DISPTREERANGE(BlockRange(), use.Def());
                JITDUMP("\n");
                return;
            }
            else
            {
                assert(location->OperIsBlk());
            }
        }
    }

    switch (locationOp)
    {
        case GT_LCL_VAR:
        case GT_LCL_FLD:
        case GT_REG_VAR:
        case GT_PHI_ARG:
            RewriteAssignmentIntoStoreLclCore(assignment, location, value, locationOp);
            BlockRange().Remove(location);
            break;

        case GT_IND:
        {
            GenTreeStoreInd* store =
                new (comp, GT_STOREIND) GenTreeStoreInd(location->TypeGet(), location->gtGetOp1(), value);

            copyFlags(store, assignment, GTF_ALL_EFFECT);
//.........这里部分代码省略.........

void Rationalizer::RewriteAssignment(LIR::Use& use)
{
    assert(use.IsInitialized());

    GenTreeOp* assignment = use.Def()->AsOp();
    assert(assignment->OperGet() == GT_ASG);

    GenTree* location = assignment->gtGetOp1();
    GenTree* value    = assignment->gtGetOp2();

    genTreeOps locationOp = location->OperGet();

#ifdef FEATURE_SIMD
    if (varTypeIsSIMD(location) && assignment->OperIsInitBlkOp())
    {
        if (location->OperGet() == GT_LCL_VAR)
        {
            var_types simdType = location->TypeGet();
            GenTree*  initVal  = assignment->gtOp.gtOp2;
            var_types baseType = comp->getBaseTypeOfSIMDLocal(location);
            if (baseType != TYP_UNKNOWN)
            {
                GenTreeSIMD* simdTree = new (comp, GT_SIMD)
                    GenTreeSIMD(simdType, initVal, SIMDIntrinsicInit, baseType, genTypeSize(simdType));
                assignment->gtOp.gtOp2 = simdTree;
                value                  = simdTree;
                initVal->gtNext        = simdTree;
                simdTree->gtPrev       = initVal;

                simdTree->gtNext = location;
                location->gtPrev = simdTree;
            }
        }
        else
        {
            assert(location->OperIsBlk());
        }
    }
#endif // FEATURE_SIMD

    switch (locationOp)
    {
        case GT_LCL_VAR:
        case GT_LCL_FLD:
        case GT_REG_VAR:
        case GT_PHI_ARG:
            RewriteAssignmentIntoStoreLclCore(assignment, location, value, locationOp);
            BlockRange().Remove(location);
            break;

        case GT_IND:
        {
            GenTreeStoreInd* store =
                new (comp, GT_STOREIND) GenTreeStoreInd(location->TypeGet(), location->gtGetOp1(), value);

            copyFlags(store, assignment, GTF_ALL_EFFECT);
            copyFlags(store, location, GTF_IND_FLAGS);

            if (assignment->IsReverseOp())
            {
                store->gtFlags |= GTF_REVERSE_OPS;
            }

            // TODO: JIT dump

            // Remove the GT_IND node and replace the assignment node with the store
            BlockRange().Remove(location);
            BlockRange().InsertBefore(assignment, store);
            use.ReplaceWith(comp, store);
            BlockRange().Remove(assignment);
        }
        break;

        case GT_CLS_VAR:
        {
            location->SetOper(GT_CLS_VAR_ADDR);
            location->gtType = TYP_BYREF;

            assignment->SetOper(GT_STOREIND);

            // TODO: JIT dump
        }
        break;

        case GT_BLK:
        case GT_OBJ:
        case GT_DYN_BLK:
        {
            assert(varTypeIsStruct(location));
            GenTreeBlk* storeBlk = location->AsBlk();
            genTreeOps  storeOper;
            switch (location->gtOper)
            {
                case GT_BLK:
                    storeOper = GT_STORE_BLK;
                    break;
                case GT_OBJ:
                    storeOper = GT_STORE_OBJ;
                    break;
                case GT_DYN_BLK:
//.........这里部分代码省略.........