Beispiel #1
0
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);
            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:
                    storeOper = GT_STORE_DYN_BLK;
                    break;
                default:
                    unreached();
            }
            JITDUMP("Rewriting GT_ASG(%s(X), Y) to %s(X,Y):\n", GenTree::NodeName(location->gtOper),
                    GenTree::NodeName(storeOper));
            storeBlk->SetOperRaw(storeOper);
            storeBlk->gtFlags &= ~GTF_DONT_CSE;
            storeBlk->gtFlags |= (assignment->gtFlags & (GTF_ALL_EFFECT | GTF_REVERSE_OPS | GTF_BLK_VOLATILE |
                                                         GTF_BLK_UNALIGNED | GTF_DONT_CSE));
            storeBlk->gtBlk.Data() = value;

            // Replace the assignment node with the store
            use.ReplaceWith(comp, storeBlk);
            BlockRange().Remove(assignment);
            DISPTREERANGE(BlockRange(), use.Def());
            JITDUMP("\n");
        }
        break;

        default:
            unreached();
            break;
    }
}
Beispiel #2
0
Compiler::fgWalkResult Rationalizer::RewriteNode(GenTree** useEdge, ArrayStack<GenTree*>& parentStack)
{
    assert(useEdge != nullptr);

    GenTree* node = *useEdge;
    assert(node != nullptr);

#ifdef DEBUG
    const bool isLateArg = (node->gtFlags & GTF_LATE_ARG) != 0;
#endif

    // First, remove any preceeding list nodes, which are not otherwise visited by the tree walk.
    //
    // NOTE: GT_FIELD_LIST head nodes, and GT_LIST nodes used by phi nodes will in fact be visited.
    for (GenTree* prev = node->gtPrev; prev != nullptr && prev->OperIsAnyList() && !(prev->OperIsFieldListHead());
         prev          = node->gtPrev)
    {
        BlockRange().Remove(prev);
    }

    // In addition, remove the current node if it is a GT_LIST node that is not an aggregate.
    if (node->OperIsAnyList())
    {
        GenTreeArgList* list = node->AsArgList();
        if (!list->OperIsFieldListHead())
        {
            BlockRange().Remove(list);
        }
        return Compiler::WALK_CONTINUE;
    }

    LIR::Use use;
    if (parentStack.Height() < 2)
    {
        use = LIR::Use::GetDummyUse(BlockRange(), *useEdge);
    }
    else
    {
        use = LIR::Use(BlockRange(), useEdge, parentStack.Index(1));
    }

    assert(node == use.Def());
    switch (node->OperGet())
    {
        case GT_ASG:
            RewriteAssignment(use);
            break;

        case GT_BOX:
            // GT_BOX at this level just passes through so get rid of it
            use.ReplaceWith(comp, node->gtGetOp1());
            BlockRange().Remove(node);
            break;

        case GT_ADDR:
            RewriteAddress(use);
            break;

        case GT_IND:
            // Clear the `GTF_IND_ASG_LHS` flag, which overlaps with `GTF_IND_REQ_ADDR_IN_REG`.
            node->gtFlags &= ~GTF_IND_ASG_LHS;
            break;

        case GT_NOP:
            // fgMorph sometimes inserts NOP nodes between defs and uses
            // supposedly 'to prevent constant folding'. In this case, remove the
            // NOP.
            if (node->gtGetOp1() != nullptr)
            {
                use.ReplaceWith(comp, node->gtGetOp1());
                BlockRange().Remove(node);
            }
            break;

        case GT_COMMA:
        {
            GenTree* op1 = node->gtGetOp1();
            if ((op1->gtFlags & GTF_ALL_EFFECT) == 0)
            {
                // The LHS has no side effects. Remove it.
                bool               isClosed    = false;
                unsigned           sideEffects = 0;
                LIR::ReadOnlyRange lhsRange    = BlockRange().GetTreeRange(op1, &isClosed, &sideEffects);

                // None of the transforms performed herein violate tree order, so these
                // should always be true.
                assert(isClosed);
                assert((sideEffects & GTF_ALL_EFFECT) == 0);

                BlockRange().Delete(comp, m_block, std::move(lhsRange));
            }

            GenTree* replacement = node->gtGetOp2();
            if (!use.IsDummyUse())
            {
                use.ReplaceWith(comp, replacement);
            }
            else
            {
                // This is a top-level comma. If the RHS has no side effects we can remove
                // it as well.
                if ((replacement->gtFlags & GTF_ALL_EFFECT) == 0)
                {
                    bool               isClosed    = false;
                    unsigned           sideEffects = 0;
                    LIR::ReadOnlyRange rhsRange    = BlockRange().GetTreeRange(replacement, &isClosed, &sideEffects);

                    // None of the transforms performed herein violate tree order, so these
                    // should always be true.
                    assert(isClosed);
                    assert((sideEffects & GTF_ALL_EFFECT) == 0);

                    BlockRange().Delete(comp, m_block, std::move(rhsRange));
                }
            }

            BlockRange().Remove(node);
        }
        break;

        case GT_ARGPLACE:
            // Remove argplace and list nodes from the execution order.
            //
            // TODO: remove phi args and phi nodes as well?
            BlockRange().Remove(node);
            break;

#ifdef _TARGET_XARCH_
        case GT_CLS_VAR:
        {
            // Class vars that are the target of an assignment will get rewritten into
            // GT_STOREIND(GT_CLS_VAR_ADDR, val) by RewriteAssignment. This check is
            // not strictly necessary--the GT_IND(GT_CLS_VAR_ADDR) pattern that would
            // otherwise be generated would also be picked up by RewriteAssignment--but
            // skipping the rewrite here saves an allocation and a bit of extra work.
            const bool isLHSOfAssignment = (use.User()->OperGet() == GT_ASG) && (use.User()->gtGetOp1() == node);
            if (!isLHSOfAssignment)
            {
                GenTree* ind = comp->gtNewOperNode(GT_IND, node->TypeGet(), node);

                node->SetOper(GT_CLS_VAR_ADDR);
                node->gtType = TYP_BYREF;

                BlockRange().InsertAfter(node, ind);
                use.ReplaceWith(comp, ind);

                // TODO: JIT dump
            }
        }
        break;
#endif // _TARGET_XARCH_

        case GT_INTRINSIC:
            // Non-target intrinsics should have already been rewritten back into user calls.
            assert(Compiler::IsTargetIntrinsic(node->gtIntrinsic.gtIntrinsicId));
            break;

#ifdef FEATURE_SIMD
        case GT_BLK:
        case GT_OBJ:
        {
            // TODO-1stClassStructs: These should have been transformed to GT_INDs, but in order
            // to preserve existing behavior, we will keep this as a block node if this is the
            // lhs of a block assignment, and either:
            // - It is a "generic" TYP_STRUCT assignment, OR
            // - It is an initblk, OR
            // - Neither the lhs or rhs are known to be of SIMD type.

            GenTree* parent  = use.User();
            bool     keepBlk = false;
            if ((parent->OperGet() == GT_ASG) && (node == parent->gtGetOp1()))
            {
                if ((node->TypeGet() == TYP_STRUCT) || parent->OperIsInitBlkOp())
                {
                    keepBlk = true;
                }
                else if (!comp->isAddrOfSIMDType(node->AsBlk()->Addr()))
                {
                    GenTree* dataSrc = parent->gtGetOp2();
                    if (!dataSrc->IsLocal() && (dataSrc->OperGet() != GT_SIMD))
                    {
                        noway_assert(dataSrc->OperIsIndir());
                        keepBlk = !comp->isAddrOfSIMDType(dataSrc->AsIndir()->Addr());
                    }
                }
            }
            RewriteSIMDOperand(use, keepBlk);
        }
        break;

        case GT_LCL_FLD:
        case GT_STORE_LCL_FLD:
            // TODO-1stClassStructs: Eliminate this.
            FixupIfSIMDLocal(node->AsLclVarCommon());
            break;

        case GT_SIMD:
        {
            noway_assert(comp->featureSIMD);
            GenTreeSIMD* simdNode = node->AsSIMD();
            unsigned     simdSize = simdNode->gtSIMDSize;
            var_types    simdType = comp->getSIMDTypeForSize(simdSize);

            // TODO-1stClassStructs: This should be handled more generally for enregistered or promoted
            // structs that are passed or returned in a different register type than their enregistered
            // type(s).
            if (simdNode->gtType == TYP_I_IMPL && simdNode->gtSIMDSize == TARGET_POINTER_SIZE)
            {
                // This happens when it is consumed by a GT_RET_EXPR.
                // It can only be a Vector2f or Vector2i.
                assert(genTypeSize(simdNode->gtSIMDBaseType) == 4);
                simdNode->gtType = TYP_SIMD8;
            }
            // Certain SIMD trees require rationalizing.
            if (simdNode->gtSIMD.gtSIMDIntrinsicID == SIMDIntrinsicInitArray)
            {
                // Rewrite this as an explicit load.
                JITDUMP("Rewriting GT_SIMD array init as an explicit load:\n");
                unsigned int baseTypeSize = genTypeSize(simdNode->gtSIMDBaseType);
                GenTree*     address = new (comp, GT_LEA) GenTreeAddrMode(TYP_BYREF, simdNode->gtOp1, simdNode->gtOp2,
                                                                      baseTypeSize, offsetof(CORINFO_Array, u1Elems));
                GenTree* ind = comp->gtNewOperNode(GT_IND, simdType, address);

                BlockRange().InsertBefore(simdNode, address, ind);
                use.ReplaceWith(comp, ind);
                BlockRange().Remove(simdNode);

                DISPTREERANGE(BlockRange(), use.Def());
                JITDUMP("\n");
            }
            else
            {
                // This code depends on the fact that NONE of the SIMD intrinsics take vector operands
                // of a different width.  If that assumption changes, we will EITHER have to make these type
                // transformations during importation, and plumb the types all the way through the JIT,
                // OR add a lot of special handling here.
                GenTree* op1 = simdNode->gtGetOp1();
                if (op1 != nullptr && op1->gtType == TYP_STRUCT)
                {
                    op1->gtType = simdType;
                }

                GenTree* op2 = simdNode->gtGetOp2();
                if (op2 != nullptr && op2->gtType == TYP_STRUCT)
                {
                    op2->gtType = simdType;
                }
            }
        }
        break;
#endif // FEATURE_SIMD

        default:
            // JCC nodes should not be present in HIR.
            assert(node->OperGet() != GT_JCC);
            break;
    }

    // Do some extra processing on top-level nodes to remove unused local reads.
    if (use.IsDummyUse() && node->OperIsLocalRead())
    {
        assert((node->gtFlags & GTF_ALL_EFFECT) == 0);

        comp->lvaDecRefCnts(node);
        BlockRange().Remove(node);
    }

    assert(isLateArg == ((use.Def()->gtFlags & GTF_LATE_ARG) != 0));

    return Compiler::WALK_CONTINUE;
}
Beispiel #3
0
// Transform CopyBlk involving SIMD vectors into stlclvar or stind of a SIMD type.
// Transformation is done if either src or dst are known to be SIMD vectors.
//
// Arguments:
//    ppTree      - A pointer-to-a-pointer for the GT_COPYBLK
//    fgWalkData  - A pointer to tree walk data providing the context
//
// Return Value:
//    None.
//
// If either the source or the dst are known to be SIMD (a lclVar or SIMD intrinsic),
// get the simdType (TYP_DOUBLE or a SIMD type for SSE2) from the size of the SIMD node.
//
// For the source:
// - If it is a SIMD intrinsic or a lvSIMDType lclVar, change the node type to simdType.
// - Otherwise, add a GT_IND of simdType.
// For the dst:
// - If it is a lclVar of a SIMD type, chanage the node type to simdType.
// - Otherwise, change it to a GT_STORE_IND of simdType
//
// TODO-Cleanup: Once SIMD types are plumbed through the frontend, this will no longer
// be required.
//
void Rationalizer::RewriteCopyBlk(LIR::Use& use)
{
#ifdef FEATURE_SIMD
    // No need to transofrm non-SIMD nodes, if featureSIMD is not enabled.
    if (!comp->featureSIMD)
    {
        return;
    }

    // See if this is a SIMD copyBlk
    GenTreeCpBlk* cpBlk   = use.Def()->AsCpBlk();
    GenTreePtr    dstAddr = cpBlk->Dest();
    GenTree*      srcAddr = cpBlk->Source();

    const bool srcIsSIMDAddr = comp->isAddrOfSIMDType(srcAddr);
    const bool dstIsSIMDAddr = comp->isAddrOfSIMDType(dstAddr);

    // Do not transform if neither src or dst is known to be a SIMD type.
    // If src tree type is something we cannot reason but if dst is known to be of a SIMD type
    // we will treat src tree as a SIMD type and vice versa.
    if (!srcIsSIMDAddr && !dstIsSIMDAddr)
    {
        return;
    }

    // At this point it is known to be a copyblk of SIMD vectors and we can
    // start transforming the original tree. Prior to this point do not perform
    // any modifications to the original tree.
    JITDUMP("\nRewriting SIMD CopyBlk\n");
    DISPTREERANGE(BlockRange(), cpBlk);

    // There are currently only three sizes supported: 8 bytes, 12 bytes, 16 bytes or the vector register length.
    GenTreeIntConCommon* sizeNode = cpBlk->Size()->AsIntConCommon();
    var_types            simdType = comp->getSIMDTypeForSize((unsigned int)sizeNode->IconValue());

    // Remove 'size' from execution order
    BlockRange().Remove(sizeNode);

    // Is destination a lclVar which is not an arg?
    // If yes then we can turn it to a stlcl.var, otherwise turn into stind.
    GenTree*   simdDst = nullptr;
    genTreeOps oper    = GT_NONE;
    if (dstIsSIMDAddr && dstAddr->OperIsLocalAddr())
    {
        simdDst         = dstAddr;
        simdDst->gtType = simdType;
        oper            = GT_STORE_LCL_VAR;

        // For structs that are padded (e.g. Vector3f, Vector3i), the morpher will have marked them
        // as GTF_VAR_USEASG.  Unmark them.
        simdDst->gtFlags &= ~(GTF_VAR_USEASG);
    }
    else
    {
        // Address of a non-local var
        simdDst = dstAddr;
        oper    = GT_STOREIND;
    }

    GenTree* simdSrc = nullptr;
    if ((srcAddr->OperGet() == GT_ADDR) && varTypeIsSIMD(srcAddr->gtGetOp1()))
    {
        // Get rid of parent node of GT_ADDR(..) if its child happens to be of a SIMD type.
        BlockRange().Remove(srcAddr);
        simdSrc = srcAddr->gtGetOp1();
    }
    else if (srcIsSIMDAddr && srcAddr->OperIsLocalAddr())
    {
        // If the source has been rewritten into a local addr node, rewrite it back into a
        // local var node.
        simdSrc = srcAddr;
        simdSrc->SetOper(loadForm(srcAddr->OperGet()));
    }
    else
    {
        // Since destination is known to be a SIMD type, src must be a SIMD type too
        // though we cannot figure it out easily enough. Transform src into
        // GT_IND(src) of simdType.
        GenTree* indir = comp->gtNewOperNode(GT_IND, simdType, srcAddr);
        BlockRange().InsertAfter(srcAddr, indir);

        cpBlk->gtGetOp1()->gtOp.gtOp2 = indir;
        simdSrc                       = indir;
    }
    simdSrc->gtType = simdType;

    // Change cpblk to either a st.lclvar or st.ind.
    // At this point we are manipulating cpblk node with the knowledge of
    // its internals (i.e. op1 is the size node, and the src & dst are in a GT_LIST on op2).
    // This logic might need to be changed if we ever restructure cpblk node.

    assert(simdDst != nullptr);
    assert(simdSrc != nullptr);

    GenTree* newNode = nullptr;
    if (oper == GT_STORE_LCL_VAR)
    {
        newNode = simdDst;
        newNode->SetOper(oper);

        GenTreeLclVar* store = newNode->AsLclVar();
        store->gtOp1         = simdSrc;
        store->gtType        = simdType;
        store->gtFlags |= ((simdSrc->gtFlags & GTF_ALL_EFFECT) | GTF_ASG);

        BlockRange().Remove(simdDst);
        BlockRange().InsertAfter(simdSrc, store);
    }
    else
    {
        assert(oper == GT_STOREIND);

        newNode = cpBlk->gtGetOp1();
        newNode->SetOper(oper);

        GenTreeStoreInd* storeInd = newNode->AsStoreInd();
        storeInd->gtType          = simdType;
        storeInd->gtFlags |= ((simdSrc->gtFlags & GTF_ALL_EFFECT) | GTF_ASG);
        storeInd->gtOp1 = simdDst;
        storeInd->gtOp2 = simdSrc;

        BlockRange().InsertBefore(cpBlk, storeInd);
    }

    use.ReplaceWith(comp, newNode);
    BlockRange().Remove(cpBlk);

    JITDUMP("After rewriting SIMD CopyBlk:\n");
    DISPTREERANGE(BlockRange(), use.Def());
    JITDUMP("\n");
#endif // FEATURE_SIMD
}
Beispiel #4
0
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:
                    storeOper = GT_STORE_DYN_BLK;
                    break;
                default:
                    unreached();
            }
            JITDUMP("Rewriting GT_ASG(%s(X), Y) to %s(X,Y):\n", GenTree::NodeName(location->gtOper),
                    GenTree::NodeName(storeOper));
            storeBlk->SetOperRaw(storeOper);
            storeBlk->gtFlags &= ~GTF_DONT_CSE;
            storeBlk->gtFlags |= (assignment->gtFlags & (GTF_ALL_EFFECT | GTF_REVERSE_OPS | GTF_BLK_VOLATILE |
                                                         GTF_BLK_UNALIGNED | GTF_BLK_INIT | GTF_DONT_CSE));
            storeBlk->gtBlk.Data() = value;

            // Replace the assignment node with the store
            use.ReplaceWith(comp, storeBlk);
            BlockRange().Remove(assignment);
            DISPTREERANGE(BlockRange(), use.Def());
            JITDUMP("\n");
        }
        break;

        default:
            unreached();
            break;
    }
}
Beispiel #5
0
// Rewrite InitBlk involving SIMD vector into stlcl.var of a SIMD type.
//
// Arguments:
//    ppTree      - A pointer-to-a-pointer for the GT_INITBLK
//    fgWalkData  - A pointer to tree walk data providing the context
//
// Return Value:
//    None.
//
// TODO-Cleanup: Once SIMD types are plumbed through the frontend, this will no longer
// be required.
//
void Rationalizer::RewriteInitBlk(LIR::Use& use)
{
#ifdef FEATURE_SIMD
    // No lowering is needed for non-SIMD nodes, so early out if featureSIMD is not enabled.
    if (!comp->featureSIMD)
    {
        return;
    }

    // See if this is a SIMD initBlk that needs to be changed to a simple st.lclVar.
    GenTreeInitBlk* initBlk = use.Def()->AsInitBlk();

    // Is the dstAddr is addr of a SIMD type lclVar?
    GenTree* dstAddr = initBlk->Dest();
    if (!comp->isAddrOfSIMDType(dstAddr) || !dstAddr->OperIsLocalAddr())
    {
        return;
    }

    unsigned lclNum = dstAddr->AsLclVarCommon()->gtLclNum;
    if (!comp->lvaTable[lclNum].lvSIMDType)
    {
        return;
    }

    var_types            baseType      = comp->lvaTable[lclNum].lvBaseType;
    CORINFO_CLASS_HANDLE typeHnd       = comp->lvaTable[lclNum].lvVerTypeInfo.GetClassHandle();
    unsigned             simdLocalSize = comp->getSIMDTypeSizeInBytes(typeHnd);

    JITDUMP("Rewriting SIMD InitBlk\n");
    DISPTREERANGE(BlockRange(), initBlk);

    assert((dstAddr->gtFlags & GTF_VAR_USEASG) == 0);

    // There are currently only three sizes supported: 8 bytes, 16 bytes or the vector register length.
    GenTreeIntConCommon* sizeNode = initBlk->Size()->AsIntConCommon();
    unsigned int         size     = (unsigned int)roundUp(sizeNode->IconValue(), TARGET_POINTER_SIZE);
    var_types            simdType = comp->getSIMDTypeForSize(size);
    assert(roundUp(simdLocalSize, TARGET_POINTER_SIZE) == size);

    GenTree*     initVal  = initBlk->InitVal();
    GenTreeSIMD* simdNode = new (comp, GT_SIMD)
        GenTreeSIMD(simdType, initVal, SIMDIntrinsicInit, baseType, (unsigned)sizeNode->IconValue());

    dstAddr->SetOper(GT_STORE_LCL_VAR);
    GenTreeLclVar* store = dstAddr->AsLclVar();
    store->gtType        = simdType;
    store->gtOp.gtOp1    = simdNode;
    store->gtFlags |= ((simdNode->gtFlags & GTF_ALL_EFFECT) | GTF_ASG);
    BlockRange().Remove(store);

    // Insert the new nodes into the block
    BlockRange().InsertAfter(initVal, simdNode, store);
    use.ReplaceWith(comp, store);

    // Remove the old size and GT_INITBLK nodes.
    BlockRange().Remove(sizeNode);
    BlockRange().Remove(initBlk);

    JITDUMP("After rewriting SIMD InitBlk:\n");
    DISPTREERANGE(BlockRange(), use.Def());
    JITDUMP("\n");
#endif // FEATURE_SIMD
}