//------------------------------------------------------------------------
// LowerRotate: Lower GT_ROL and GT_ROR nodes.
//
// Arguments:
// tree - the node to lower
//
// Return Value:
// None.
//
void Lowering::LowerRotate(GenTree* tree)
{
if (tree->OperGet() == GT_ROL)
{
// There is no ROL instruction on ARM. Convert ROL into ROR.
GenTree* rotatedValue = tree->gtOp.gtOp1;
unsigned rotatedValueBitSize = genTypeSize(rotatedValue->gtType) * 8;
GenTree* rotateLeftIndexNode = tree->gtOp.gtOp2;
if (rotateLeftIndexNode->IsCnsIntOrI())
{
ssize_t rotateLeftIndex = rotateLeftIndexNode->gtIntCon.gtIconVal;
ssize_t rotateRightIndex = rotatedValueBitSize - rotateLeftIndex;
rotateLeftIndexNode->gtIntCon.gtIconVal = rotateRightIndex;
}
else
{
GenTree* 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)
{
ContainCheckShiftRotate(tree->AsOp());
TreeNodeInfo* info = &(tree->gtLsraInfo);
LinearScan* l = m_lsra;
GenTreePtr shiftBy = tree->gtOp.gtOp2;
info->srcCount = shiftBy->isContained() ? 1 : 2;
info->dstCount = 1;
#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.
GenTreePtr source = tree->gtOp.gtOp1;
if (tree->OperGet() == GT_LSH_HI || tree->OperGet() == GT_RSH_LO)
{
assert((source->OperGet() == GT_LONG) && source->isContained());
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_
}
