//------------------------------------------------------------------------
// LowerRotate: Lower GT_ROL and GT_ROR nodes.
//
// Arguments:
// tree - the node to lower
//
// Return Value:
// None.
//
void Lowering::LowerRotate(GenTreePtr tree)
{
if (tree->OperGet() == GT_ROL)
{
// There is no ROL instruction on ARM. Convert ROL into ROR.
GenTreePtr rotatedValue = tree->gtOp.gtOp1;
unsigned rotatedValueBitSize = genTypeSize(rotatedValue->gtType) * 8;
GenTreePtr rotateLeftIndexNode = tree->gtOp.gtOp2;
if (rotateLeftIndexNode->IsCnsIntOrI())
{
ssize_t rotateLeftIndex = rotateLeftIndexNode->gtIntCon.gtIconVal;
ssize_t rotateRightIndex = rotatedValueBitSize - rotateLeftIndex;
rotateLeftIndexNode->gtIntCon.gtIconVal = rotateRightIndex;
}
else
{
GenTreePtr tmp =
comp->gtNewOperNode(GT_NEG, genActualType(rotateLeftIndexNode->gtType), rotateLeftIndexNode);
BlockRange().InsertAfter(rotateLeftIndexNode, tmp);
tree->gtOp.gtOp2 = tmp;
}
tree->ChangeOper(GT_ROR);
}
ContainCheckShiftRotate(tree->AsOp());
}
//------------------------------------------------------------------------
// TreeNodeInfoInitShiftRotate: Set the NodeInfo for a shift or rotate.
//
// Arguments:
// tree - The node of interest
//
// Return Value:
// None.
//
void Lowering::TreeNodeInfoInitShiftRotate(GenTree* tree)
{
TreeNodeInfo* info = &(tree->gtLsraInfo);
LinearScan* l = m_lsra;
info->srcCount = 2;
info->dstCount = 1;
GenTreePtr shiftBy = tree->gtOp.gtOp2;
GenTreePtr source = tree->gtOp.gtOp1;
if (shiftBy->IsCnsIntOrI())
{
MakeSrcContained(tree, shiftBy);
}
#ifdef _TARGET_ARM_
// The first operand of a GT_LSH_HI and GT_RSH_LO oper is a GT_LONG so that
// we can have a three operand form. Increment the srcCount.
if (tree->OperGet() == GT_LSH_HI || tree->OperGet() == GT_RSH_LO)
{
assert(source->OperGet() == GT_LONG);
source->SetContained();
info->srcCount++;
if (tree->OperGet() == GT_LSH_HI)
{
GenTreePtr sourceLo = source->gtOp.gtOp1;
sourceLo->gtLsraInfo.isDelayFree = true;
}
else
{
GenTreePtr sourceHi = source->gtOp.gtOp2;
sourceHi->gtLsraInfo.isDelayFree = true;
}
source->gtLsraInfo.hasDelayFreeSrc = true;
info->hasDelayFreeSrc = true;
}
#endif // _TARGET_ARM_
}
//------------------------------------------------------------------------
// ContainCheckShiftRotate: Determine whether a mul op's operands should be contained.
//
// Arguments:
// node - the node we care about
//
void Lowering::ContainCheckShiftRotate(GenTreeOp* node)
{
GenTreePtr shiftBy = node->gtOp2;
#ifdef _TARGET_ARM_
GenTreePtr source = node->gtOp1;
if (node->OperIs(GT_LSH_HI, GT_RSH_LO))
{
assert(source->OperGet() == GT_LONG);
MakeSrcContained(node, source);
}
#else // !_TARGET_ARM_
assert(node->OperIsShiftOrRotate());
#endif // !_TARGET_ARM_
if (shiftBy->IsCnsIntOrI())
{
MakeSrcContained(node, shiftBy);
}
}
//------------------------------------------------------------------------
// LowerBlockStore: Set block store type
//
// Arguments:
// blkNode - The block store node of interest
//
// Return Value:
// None.
//
void Lowering::LowerBlockStore(GenTreeBlk* blkNode)
{
GenTree* dstAddr = blkNode->Addr();
unsigned size = blkNode->gtBlkSize;
GenTree* source = blkNode->Data();
Compiler* compiler = comp;
// Sources are dest address and initVal or source.
GenTreePtr srcAddrOrFill = nullptr;
bool isInitBlk = blkNode->OperIsInitBlkOp();
if (!isInitBlk)
{
// CopyObj or CopyBlk
if ((blkNode->OperGet() == GT_STORE_OBJ) && ((blkNode->AsObj()->gtGcPtrCount == 0) || blkNode->gtBlkOpGcUnsafe))
{
blkNode->SetOper(GT_STORE_BLK);
}
if (source->gtOper == GT_IND)
{
srcAddrOrFill = blkNode->Data()->gtGetOp1();
}
}
if (isInitBlk)
{
GenTreePtr initVal = source;
if (initVal->OperIsInitVal())
{
initVal->SetContained();
initVal = initVal->gtGetOp1();
}
srcAddrOrFill = initVal;
#ifdef _TARGET_ARM64_
if ((size != 0) && (size <= INITBLK_UNROLL_LIMIT) && initVal->IsCnsIntOrI())
{
// TODO-ARM-CQ: Currently we generate a helper call for every
// initblk we encounter. Later on we should implement loop unrolling
// code sequences to improve CQ.
// For reference see the code in LowerXArch.cpp.
NYI_ARM("initblk loop unrolling is currently not implemented.");
// The fill value of an initblk is interpreted to hold a
// value of (unsigned int8) however a constant of any size
// may practically reside on the evaluation stack. So extract
// the lower byte out of the initVal constant and replicate
// it to a larger constant whose size is sufficient to support
// the largest width store of the desired inline expansion.
ssize_t fill = initVal->gtIntCon.gtIconVal & 0xFF;
if (fill == 0)
{
MakeSrcContained(blkNode, source);
}
else if (size < REGSIZE_BYTES)
{
initVal->gtIntCon.gtIconVal = 0x01010101 * fill;
}
else
{
initVal->gtIntCon.gtIconVal = 0x0101010101010101LL * fill;
initVal->gtType = TYP_LONG;
}
blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindUnroll;
}
else
#endif // _TARGET_ARM64_
{
blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindHelper;
}
}
else
{
// CopyObj or CopyBlk
// Sources are src and dest and size if not constant.
if (blkNode->OperGet() == GT_STORE_OBJ)
{
// CopyObj
GenTreeObj* objNode = blkNode->AsObj();
unsigned slots = objNode->gtSlots;
#ifdef DEBUG
// CpObj must always have at least one GC-Pointer as a member.
assert(objNode->gtGcPtrCount > 0);
assert(dstAddr->gtType == TYP_BYREF || dstAddr->gtType == TYP_I_IMPL);
CORINFO_CLASS_HANDLE clsHnd = objNode->gtClass;
size_t classSize = compiler->info.compCompHnd->getClassSize(clsHnd);
size_t blkSize = roundUp(classSize, TARGET_POINTER_SIZE);
// Currently, the EE always round up a class data structure so
// we are not handling the case where we have a non multiple of pointer sized
// struct. This behavior may change in the future so in order to keeps things correct
// let's assert it just to be safe. Going forward we should simply
// handle this case.
assert(classSize == blkSize);
assert((blkSize / TARGET_POINTER_SIZE) == slots);
assert(objNode->HasGCPtr());
#endif
blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindUnroll;
}
else // CopyBlk
{
// In case of a CpBlk with a constant size and less than CPBLK_UNROLL_LIMIT size
// we should unroll the loop to improve CQ.
// For reference see the code in lowerxarch.cpp.
if ((size != 0) && (size <= INITBLK_UNROLL_LIMIT))
{
blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindUnroll;
}
else
{
// In case we have a constant integer this means we went beyond
// CPBLK_UNROLL_LIMIT bytes of size, still we should never have the case of
// any GC-Pointers in the src struct.
blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindHelper;
}
}
// CopyObj or CopyBlk
if (source->gtOper == GT_IND)
{
MakeSrcContained(blkNode, source);
}
else if (!source->IsMultiRegCall() && !source->OperIsSIMD())
{
assert(source->IsLocal());
MakeSrcContained(blkNode, source);
}
}
}
