//------------------------------------------------------------------------
// ContainCheckIndir: Determine whether operands of an indir should be contained.
//
// Arguments:
//    indirNode - The indirection node of interest
//
// Notes:
//    This is called for both store and load indirections.
//
// Return Value:
//    None.
//
void Lowering::ContainCheckIndir(GenTreeIndir* indirNode)
{
    // If this is the rhs of a block copy it will be handled when we handle the store.
    if (indirNode->TypeGet() == TYP_STRUCT)
    {
        return;
    }

#ifdef FEATURE_SIMD
    // If indirTree is of TYP_SIMD12, don't mark addr as contained
    // so that it always get computed to a register.  This would
    // mean codegen side logic doesn't need to handle all possible
    // addr expressions that could be contained.
    //
    // TODO-ARM64-CQ: handle other addr mode expressions that could be marked
    // as contained.
    if (indirNode->TypeGet() == TYP_SIMD12)
    {
        return;
    }
#endif // FEATURE_SIMD

    GenTree* addr          = indirNode->Addr();
    bool     makeContained = true;
    if ((addr->OperGet() == GT_LEA) && IsSafeToContainMem(indirNode, addr))
    {
        GenTreeAddrMode* lea   = addr->AsAddrMode();
        GenTree*         base  = lea->Base();
        GenTree*         index = lea->Index();
        int              cns   = lea->Offset();

#ifdef _TARGET_ARM_
        // ARM floating-point load/store doesn't support a form similar to integer
        // ldr Rdst, [Rbase + Roffset] with offset in a register. The only supported
        // form is vldr Rdst, [Rbase + imm] with a more limited constraint on the imm.
        if (lea->HasIndex() || !emitter::emitIns_valid_imm_for_vldst_offset(cns))
        {
            if (indirNode->OperGet() == GT_STOREIND)
            {
                if (varTypeIsFloating(indirNode->AsStoreInd()->Data()))
                {
                    makeContained = false;
                }
            }
            else if (indirNode->OperGet() == GT_IND)
            {
                if (varTypeIsFloating(indirNode))
                {
                    makeContained = false;
                }
            }
        }
#endif
        if (makeContained)
        {
            MakeSrcContained(indirNode, addr);
        }
    }
}
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//------------------------------------------------------------------------
// ContainCheckIndir: Determine whether operands of an indir should be contained.
//
// Arguments:
//    indirNode - The indirection node of interest
//
// Notes:
//    This is called for both store and load indirections.
//
// Return Value:
//    None.
//
void Lowering::ContainCheckIndir(GenTreeIndir* indirNode)
{
    // If this is the rhs of a block copy it will be handled when we handle the store.
    if (indirNode->TypeGet() == TYP_STRUCT)
    {
        return;
    }

    GenTree* addr          = indirNode->Addr();
    bool     makeContained = true;
    if ((addr->OperGet() == GT_LEA) && IsSafeToContainMem(indirNode, addr))
    {
        GenTreeAddrMode* lea   = addr->AsAddrMode();
        GenTree*         base  = lea->Base();
        GenTree*         index = lea->Index();
        int              cns   = lea->Offset();

#ifdef _TARGET_ARM_
        // ARM floating-point load/store doesn't support a form similar to integer
        // ldr Rdst, [Rbase + Roffset] with offset in a register. The only supported
        // form is vldr Rdst, [Rbase + imm] with a more limited constraint on the imm.
        if (lea->HasIndex() || !emitter::emitIns_valid_imm_for_vldst_offset(cns))
        {
            if (indirNode->OperGet() == GT_STOREIND)
            {
                if (varTypeIsFloating(indirNode->AsStoreInd()->Data()))
                {
                    makeContained = false;
                }
            }
            else if (indirNode->OperGet() == GT_IND)
            {
                if (varTypeIsFloating(indirNode))
                {
                    makeContained = false;
                }
            }
        }
#endif
        if (makeContained)
        {
            MakeSrcContained(indirNode, addr);
        }
    }
}
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//------------------------------------------------------------------------
// TreeNodeInfoInitIndir: Specify register requirements for address expression
//                       of an indirection operation.
//
// Arguments:
//    indirTree - GT_IND, GT_STOREIND, block node or GT_NULLCHECK gentree node
//
void Lowering::TreeNodeInfoInitIndir(GenTreePtr indirTree)
{
    assert(indirTree->OperIsIndir());
    // If this is the rhs of a block copy (i.e. non-enregisterable struct),
    // it has no register requirements.
    if (indirTree->TypeGet() == TYP_STRUCT)
    {
        return;
    }

    GenTreePtr    addr = indirTree->gtGetOp1();
    TreeNodeInfo* info = &(indirTree->gtLsraInfo);

    GenTreePtr base  = nullptr;
    GenTreePtr index = nullptr;
    unsigned   cns   = 0;
    unsigned   mul;
    bool       rev;
    bool       modifiedSources = false;
    bool       makeContained   = true;

    if ((addr->OperGet() == GT_LEA) && IsSafeToContainMem(indirTree, addr))
    {
        GenTreeAddrMode* lea = addr->AsAddrMode();
        base                 = lea->Base();
        index                = lea->Index();
        cns                  = lea->gtOffset;

#ifdef _TARGET_ARM_
        // ARM floating-point load/store doesn't support a form similar to integer
        // ldr Rdst, [Rbase + Roffset] with offset in a register. The only supported
        // form is vldr Rdst, [Rbase + imm] with a more limited constraint on the imm.
        if (lea->HasIndex() || !emitter::emitIns_valid_imm_for_vldst_offset(cns))
        {
            if (indirTree->OperGet() == GT_STOREIND)
            {
                if (varTypeIsFloating(indirTree->AsStoreInd()->Data()))
                {
                    makeContained = false;
                }
            }
            else if (indirTree->OperGet() == GT_IND)
            {
                if (varTypeIsFloating(indirTree))
                {
                    makeContained = false;
                }
            }
        }
#endif

        if (makeContained)
        {
            m_lsra->clearOperandCounts(addr);
            addr->SetContained();
            // The srcCount is decremented because addr is now "contained",
            // then we account for the base and index below, if they are non-null.
            info->srcCount--;
        }
    }
    else if (comp->codeGen->genCreateAddrMode(addr, -1, true, 0, &rev, &base, &index, &mul, &cns, true /*nogen*/) &&
             !(modifiedSources = AreSourcesPossiblyModifiedLocals(indirTree, base, index)))
    {
        // An addressing mode will be constructed that may cause some
        // nodes to not need a register, and cause others' lifetimes to be extended
        // to the GT_IND or even its parent if it's an assignment

        assert(base != addr);
        m_lsra->clearOperandCounts(addr);
        addr->SetContained();

        // Traverse the computation below GT_IND to find the operands
        // for the addressing mode, marking the various constants and
        // intermediate results as not consuming/producing.
        // If the traversal were more complex, we might consider using
        // a traversal function, but the addressing mode is only made
        // up of simple arithmetic operators, and the code generator
        // only traverses one leg of each node.

        bool       foundBase  = (base == nullptr);
        bool       foundIndex = (index == nullptr);
        GenTreePtr nextChild  = nullptr;
        for (GenTreePtr child = addr; child != nullptr && !child->OperIsLeaf(); child = nextChild)
        {
            nextChild      = nullptr;
            GenTreePtr op1 = child->gtOp.gtOp1;
            GenTreePtr op2 = (child->OperIsBinary()) ? child->gtOp.gtOp2 : nullptr;

            if (op1 == base)
            {
                foundBase = true;
            }
            else if (op1 == index)
            {
                foundIndex = true;
            }
            else
            {
                m_lsra->clearOperandCounts(op1);
                op1->SetContained();
                if (!op1->OperIsLeaf())
                {
                    nextChild = op1;
                }
            }

            if (op2 != nullptr)
            {
                if (op2 == base)
                {
                    foundBase = true;
                }
                else if (op2 == index)
                {
                    foundIndex = true;
                }
                else
                {
                    m_lsra->clearOperandCounts(op2);
                    op2->SetContained();
                    if (!op2->OperIsLeaf())
                    {
                        assert(nextChild == nullptr);
                        nextChild = op2;
                    }
                }
            }
        }
        assert(foundBase && foundIndex);
        info->srcCount--; // it gets incremented below.
    }
    else if (addr->gtOper == GT_ARR_ELEM)
    {
        // The GT_ARR_ELEM consumes all the indices and produces the offset.
        // The array object lives until the mem access.
        // We also consume the target register to which the address is
        // computed

        info->srcCount++;
        assert(addr->gtLsraInfo.srcCount >= 2);
        addr->gtLsraInfo.srcCount -= 1;
    }
    else
    {
        // it is nothing but a plain indir
        info->srcCount--; // base gets added in below
        base = addr;
    }

    if (!makeContained)
    {
        return;
    }

    if (base != nullptr)
    {
        info->srcCount++;
    }
    if (index != nullptr && !modifiedSources)
    {
        info->srcCount++;
    }

    // On ARM we may need a single internal register
    // (when both conditions are true then we still only need a single internal register)
    if ((index != nullptr) && (cns != 0))
    {
        // ARM does not support both Index and offset so we need an internal register
        info->internalIntCount = 1;
    }
    else if (!emitter::emitIns_valid_imm_for_ldst_offset(cns, emitTypeSize(indirTree)))
    {
        // This offset can't be contained in the ldr/str instruction, so we need an internal register
        info->internalIntCount = 1;
    }
}