Use the space freed up by sparc and zaurus to import LLVM.

ok hackroom@

1 files changed, 1978 insertions, 0 deletions

diff --git a/gnu/llvm/lib/Target/XCore/XCoreISelLowering.cpp b/gnu/llvm/lib/Target/XCore/XCoreISelLowering.cpp
new file mode 100644
index 00000000000..105b2cfb1be
--- /dev/null
+++ b/gnu/llvm/lib/Target/XCore/XCoreISelLowering.cpp
@@ -0,0 +1,1978 @@
+//===-- XCoreISelLowering.cpp - XCore DAG Lowering Implementation ---------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the XCoreTargetLowering class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "XCoreISelLowering.h"
+#include "XCore.h"
+#include "XCoreMachineFunctionInfo.h"
+#include "XCoreSubtarget.h"
+#include "XCoreTargetMachine.h"
+#include "XCoreTargetObjectFile.h"
+#include "llvm/CodeGen/CallingConvLower.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineJumpTableInfo.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/SelectionDAGISel.h"
+#include "llvm/CodeGen/ValueTypes.h"
+#include "llvm/IR/CallingConv.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/GlobalAlias.h"
+#include "llvm/IR/GlobalVariable.h"
+#include "llvm/IR/Intrinsics.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+
+using namespace llvm;
+
+#define DEBUG_TYPE "xcore-lower"
+
+const char *XCoreTargetLowering::
+getTargetNodeName(unsigned Opcode) const
+{
+  switch ((XCoreISD::NodeType)Opcode)
+  {
+    case XCoreISD::FIRST_NUMBER      : break;
+    case XCoreISD::BL                : return "XCoreISD::BL";
+    case XCoreISD::PCRelativeWrapper : return "XCoreISD::PCRelativeWrapper";
+    case XCoreISD::DPRelativeWrapper : return "XCoreISD::DPRelativeWrapper";
+    case XCoreISD::CPRelativeWrapper : return "XCoreISD::CPRelativeWrapper";
+    case XCoreISD::LDWSP             : return "XCoreISD::LDWSP";
+    case XCoreISD::STWSP             : return "XCoreISD::STWSP";
+    case XCoreISD::RETSP             : return "XCoreISD::RETSP";
+    case XCoreISD::LADD              : return "XCoreISD::LADD";
+    case XCoreISD::LSUB              : return "XCoreISD::LSUB";
+    case XCoreISD::LMUL              : return "XCoreISD::LMUL";
+    case XCoreISD::MACCU             : return "XCoreISD::MACCU";
+    case XCoreISD::MACCS             : return "XCoreISD::MACCS";
+    case XCoreISD::CRC8              : return "XCoreISD::CRC8";
+    case XCoreISD::BR_JT             : return "XCoreISD::BR_JT";
+    case XCoreISD::BR_JT32           : return "XCoreISD::BR_JT32";
+    case XCoreISD::FRAME_TO_ARGS_OFFSET : return "XCoreISD::FRAME_TO_ARGS_OFFSET";
+    case XCoreISD::EH_RETURN         : return "XCoreISD::EH_RETURN";
+    case XCoreISD::MEMBARRIER        : return "XCoreISD::MEMBARRIER";
+  }
+  return nullptr;
+}
+
+XCoreTargetLowering::XCoreTargetLowering(const TargetMachine &TM,
+                                         const XCoreSubtarget &Subtarget)
+    : TargetLowering(TM), TM(TM), Subtarget(Subtarget) {
+
+  // Set up the register classes.
+  addRegisterClass(MVT::i32, &XCore::GRRegsRegClass);
+
+  // Compute derived properties from the register classes
+  computeRegisterProperties(Subtarget.getRegisterInfo());
+
+  setStackPointerRegisterToSaveRestore(XCore::SP);
+
+  setSchedulingPreference(Sched::Source);
+
+  // Use i32 for setcc operations results (slt, sgt, ...).
+  setBooleanContents(ZeroOrOneBooleanContent);
+  setBooleanVectorContents(ZeroOrOneBooleanContent); // FIXME: Is this correct?
+
+  // XCore does not have the NodeTypes below.
+  setOperationAction(ISD::BR_CC,     MVT::i32,   Expand);
+  setOperationAction(ISD::SELECT_CC, MVT::i32,   Expand);
+  setOperationAction(ISD::ADDC, MVT::i32, Expand);
+  setOperationAction(ISD::ADDE, MVT::i32, Expand);
+  setOperationAction(ISD::SUBC, MVT::i32, Expand);
+  setOperationAction(ISD::SUBE, MVT::i32, Expand);
+
+  // 64bit
+  setOperationAction(ISD::ADD, MVT::i64, Custom);
+  setOperationAction(ISD::SUB, MVT::i64, Custom);
+  setOperationAction(ISD::SMUL_LOHI, MVT::i32, Custom);
+  setOperationAction(ISD::UMUL_LOHI, MVT::i32, Custom);
+  setOperationAction(ISD::MULHS, MVT::i32, Expand);
+  setOperationAction(ISD::MULHU, MVT::i32, Expand);
+  setOperationAction(ISD::SHL_PARTS, MVT::i32, Expand);
+  setOperationAction(ISD::SRA_PARTS, MVT::i32, Expand);
+  setOperationAction(ISD::SRL_PARTS, MVT::i32, Expand);
+
+  // Bit Manipulation
+  setOperationAction(ISD::CTPOP, MVT::i32, Expand);
+  setOperationAction(ISD::ROTL , MVT::i32, Expand);
+  setOperationAction(ISD::ROTR , MVT::i32, Expand);
+  setOperationAction(ISD::CTTZ_ZERO_UNDEF, MVT::i32, Expand);
+  setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i32, Expand);
+
+  setOperationAction(ISD::TRAP, MVT::Other, Legal);
+
+  // Jump tables.
+  setOperationAction(ISD::BR_JT, MVT::Other, Custom);
+
+  setOperationAction(ISD::GlobalAddress, MVT::i32,   Custom);
+  setOperationAction(ISD::BlockAddress, MVT::i32 , Custom);
+
+  // Conversion of i64 -> double produces constantpool nodes
+  setOperationAction(ISD::ConstantPool, MVT::i32,   Custom);
+
+  // Loads
+  for (MVT VT : MVT::integer_valuetypes()) {
+    setLoadExtAction(ISD::EXTLOAD, VT, MVT::i1, Promote);
+    setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i1, Promote);
+    setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i1, Promote);
+
+    setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i8, Expand);
+    setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i16, Expand);
+  }
+
+  // Custom expand misaligned loads / stores.
+  setOperationAction(ISD::LOAD, MVT::i32, Custom);
+  setOperationAction(ISD::STORE, MVT::i32, Custom);
+
+  // Varargs
+  setOperationAction(ISD::VAEND, MVT::Other, Expand);
+  setOperationAction(ISD::VACOPY, MVT::Other, Expand);
+  setOperationAction(ISD::VAARG, MVT::Other, Custom);
+  setOperationAction(ISD::VASTART, MVT::Other, Custom);
+
+  // Dynamic stack
+  setOperationAction(ISD::STACKSAVE, MVT::Other, Expand);
+  setOperationAction(ISD::STACKRESTORE, MVT::Other, Expand);
+  setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Expand);
+
+  // Exception handling
+  setOperationAction(ISD::EH_RETURN, MVT::Other, Custom);
+  setOperationAction(ISD::FRAME_TO_ARGS_OFFSET, MVT::i32, Custom);
+
+  // Atomic operations
+  // We request a fence for ATOMIC_* instructions, to reduce them to Monotonic.
+  // As we are always Sequential Consistent, an ATOMIC_FENCE becomes a no OP.
+  setInsertFencesForAtomic(true);
+  setOperationAction(ISD::ATOMIC_FENCE, MVT::Other, Custom);
+  setOperationAction(ISD::ATOMIC_LOAD, MVT::i32, Custom);
+  setOperationAction(ISD::ATOMIC_STORE, MVT::i32, Custom);
+
+  // TRAMPOLINE is custom lowered.
+  setOperationAction(ISD::INIT_TRAMPOLINE, MVT::Other, Custom);
+  setOperationAction(ISD::ADJUST_TRAMPOLINE, MVT::Other, Custom);
+
+  // We want to custom lower some of our intrinsics.
+  setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::Other, Custom);
+
+  MaxStoresPerMemset = MaxStoresPerMemsetOptSize = 4;
+  MaxStoresPerMemmove = MaxStoresPerMemmoveOptSize
+    = MaxStoresPerMemcpy = MaxStoresPerMemcpyOptSize = 2;
+
+  // We have target-specific dag combine patterns for the following nodes:
+  setTargetDAGCombine(ISD::STORE);
+  setTargetDAGCombine(ISD::ADD);
+  setTargetDAGCombine(ISD::INTRINSIC_VOID);
+  setTargetDAGCombine(ISD::INTRINSIC_W_CHAIN);
+
+  setMinFunctionAlignment(1);
+  setPrefFunctionAlignment(2);
+}
+
+bool XCoreTargetLowering::isZExtFree(SDValue Val, EVT VT2) const {
+  if (Val.getOpcode() != ISD::LOAD)
+    return false;
+
+  EVT VT1 = Val.getValueType();
+  if (!VT1.isSimple() || !VT1.isInteger() ||
+      !VT2.isSimple() || !VT2.isInteger())
+    return false;
+
+  switch (VT1.getSimpleVT().SimpleTy) {
+  default: break;
+  case MVT::i8:
+    return true;
+  }
+
+  return false;
+}
+
+SDValue XCoreTargetLowering::
+LowerOperation(SDValue Op, SelectionDAG &DAG) const {
+  switch (Op.getOpcode())
+  {
+  case ISD::EH_RETURN:          return LowerEH_RETURN(Op, DAG);
+  case ISD::GlobalAddress:      return LowerGlobalAddress(Op, DAG);
+  case ISD::BlockAddress:       return LowerBlockAddress(Op, DAG);
+  case ISD::ConstantPool:       return LowerConstantPool(Op, DAG);
+  case ISD::BR_JT:              return LowerBR_JT(Op, DAG);
+  case ISD::LOAD:               return LowerLOAD(Op, DAG);
+  case ISD::STORE:              return LowerSTORE(Op, DAG);
+  case ISD::VAARG:              return LowerVAARG(Op, DAG);
+  case ISD::VASTART:            return LowerVASTART(Op, DAG);
+  case ISD::SMUL_LOHI:          return LowerSMUL_LOHI(Op, DAG);
+  case ISD::UMUL_LOHI:          return LowerUMUL_LOHI(Op, DAG);
+  // FIXME: Remove these when LegalizeDAGTypes lands.
+  case ISD::ADD:
+  case ISD::SUB:                return ExpandADDSUB(Op.getNode(), DAG);
+  case ISD::FRAMEADDR:          return LowerFRAMEADDR(Op, DAG);
+  case ISD::RETURNADDR:         return LowerRETURNADDR(Op, DAG);
+  case ISD::FRAME_TO_ARGS_OFFSET: return LowerFRAME_TO_ARGS_OFFSET(Op, DAG);
+  case ISD::INIT_TRAMPOLINE:    return LowerINIT_TRAMPOLINE(Op, DAG);
+  case ISD::ADJUST_TRAMPOLINE:  return LowerADJUST_TRAMPOLINE(Op, DAG);
+  case ISD::INTRINSIC_WO_CHAIN: return LowerINTRINSIC_WO_CHAIN(Op, DAG);
+  case ISD::ATOMIC_FENCE:       return LowerATOMIC_FENCE(Op, DAG);
+  case ISD::ATOMIC_LOAD:        return LowerATOMIC_LOAD(Op, DAG);
+  case ISD::ATOMIC_STORE:       return LowerATOMIC_STORE(Op, DAG);
+  default:
+    llvm_unreachable("unimplemented operand");
+  }
+}
+
+/// ReplaceNodeResults - Replace the results of node with an illegal result
+/// type with new values built out of custom code.
+void XCoreTargetLowering::ReplaceNodeResults(SDNode *N,
+                                             SmallVectorImpl<SDValue>&Results,
+                                             SelectionDAG &DAG) const {
+  switch (N->getOpcode()) {
+  default:
+    llvm_unreachable("Don't know how to custom expand this!");
+  case ISD::ADD:
+  case ISD::SUB:
+    Results.push_back(ExpandADDSUB(N, DAG));
+    return;
+  }
+}
+
+//===----------------------------------------------------------------------===//
+//  Misc Lower Operation implementation
+//===----------------------------------------------------------------------===//
+
+SDValue XCoreTargetLowering::getGlobalAddressWrapper(SDValue GA,
+                                                     const GlobalValue *GV,
+                                                     SelectionDAG &DAG) const {
+  // FIXME there is no actual debug info here
+  SDLoc dl(GA);
+
+  if (GV->getType()->getElementType()->isFunctionTy())
+    return DAG.getNode(XCoreISD::PCRelativeWrapper, dl, MVT::i32, GA);
+
+  const auto *GVar = dyn_cast<GlobalVariable>(GV);
+  if ((GV->hasSection() && StringRef(GV->getSection()).startswith(".cp.")) ||
+      (GVar && GVar->isConstant() && GV->hasLocalLinkage()))
+    return DAG.getNode(XCoreISD::CPRelativeWrapper, dl, MVT::i32, GA);
+
+  return DAG.getNode(XCoreISD::DPRelativeWrapper, dl, MVT::i32, GA);
+}
+
+static bool IsSmallObject(const GlobalValue *GV, const XCoreTargetLowering &XTL) {
+  if (XTL.getTargetMachine().getCodeModel() == CodeModel::Small)
+    return true;
+
+  Type *ObjType = GV->getType()->getPointerElementType();
+  if (!ObjType->isSized())
+    return false;
+
+  auto &DL = GV->getParent()->getDataLayout();
+  unsigned ObjSize = DL.getTypeAllocSize(ObjType);
+  return ObjSize < CodeModelLargeSize && ObjSize != 0;
+}
+
+SDValue XCoreTargetLowering::
+LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const
+{
+  const GlobalAddressSDNode *GN = cast<GlobalAddressSDNode>(Op);
+  const GlobalValue *GV = GN->getGlobal();
+  SDLoc DL(GN);
+  int64_t Offset = GN->getOffset();
+  if (IsSmallObject(GV, *this)) {
+    // We can only fold positive offsets that are a multiple of the word size.
+    int64_t FoldedOffset = std::max(Offset & ~3, (int64_t)0);
+    SDValue GA = DAG.getTargetGlobalAddress(GV, DL, MVT::i32, FoldedOffset);
+    GA = getGlobalAddressWrapper(GA, GV, DAG);
+    // Handle the rest of the offset.
+    if (Offset != FoldedOffset) {
+      SDValue Remaining = DAG.getConstant(Offset - FoldedOffset, DL, MVT::i32);
+      GA = DAG.getNode(ISD::ADD, DL, MVT::i32, GA, Remaining);
+    }
+    return GA;
+  } else {
+    // Ideally we would not fold in offset with an index <= 11.
+    Type *Ty = Type::getInt8PtrTy(*DAG.getContext());
+    Constant *GA = ConstantExpr::getBitCast(const_cast<GlobalValue*>(GV), Ty);
+    Ty = Type::getInt32Ty(*DAG.getContext());
+    Constant *Idx = ConstantInt::get(Ty, Offset);
+    Constant *GAI = ConstantExpr::getGetElementPtr(
+        Type::getInt8Ty(*DAG.getContext()), GA, Idx);
+    SDValue CP = DAG.getConstantPool(GAI, MVT::i32);
+    return DAG.getLoad(getPointerTy(DAG.getDataLayout()), DL,
+                       DAG.getEntryNode(), CP, MachinePointerInfo(), false,
+                       false, false, 0);
+  }
+}
+
+SDValue XCoreTargetLowering::
+LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const
+{
+  SDLoc DL(Op);
+  auto PtrVT = getPointerTy(DAG.getDataLayout());
+  const BlockAddress *BA = cast<BlockAddressSDNode>(Op)->getBlockAddress();
+  SDValue Result = DAG.getTargetBlockAddress(BA, PtrVT);
+
+  return DAG.getNode(XCoreISD::PCRelativeWrapper, DL, PtrVT, Result);
+}
+
+SDValue XCoreTargetLowering::
+LowerConstantPool(SDValue Op, SelectionDAG &DAG) const
+{
+  ConstantPoolSDNode *CP = cast<ConstantPoolSDNode>(Op);
+  // FIXME there isn't really debug info here
+  SDLoc dl(CP);
+  EVT PtrVT = Op.getValueType();
+  SDValue Res;
+  if (CP->isMachineConstantPoolEntry()) {
+    Res = DAG.getTargetConstantPool(CP->getMachineCPVal(), PtrVT,
+                                    CP->getAlignment(), CP->getOffset());
+  } else {
+    Res = DAG.getTargetConstantPool(CP->getConstVal(), PtrVT,
+                                    CP->getAlignment(), CP->getOffset());
+  }
+  return DAG.getNode(XCoreISD::CPRelativeWrapper, dl, MVT::i32, Res);
+}
+
+unsigned XCoreTargetLowering::getJumpTableEncoding() const {
+  return MachineJumpTableInfo::EK_Inline;
+}
+
+SDValue XCoreTargetLowering::
+LowerBR_JT(SDValue Op, SelectionDAG &DAG) const
+{
+  SDValue Chain = Op.getOperand(0);
+  SDValue Table = Op.getOperand(1);
+  SDValue Index = Op.getOperand(2);
+  SDLoc dl(Op);
+  JumpTableSDNode *JT = cast<JumpTableSDNode>(Table);
+  unsigned JTI = JT->getIndex();
+  MachineFunction &MF = DAG.getMachineFunction();
+  const MachineJumpTableInfo *MJTI = MF.getJumpTableInfo();
+  SDValue TargetJT = DAG.getTargetJumpTable(JT->getIndex(), MVT::i32);
+
+  unsigned NumEntries = MJTI->getJumpTables()[JTI].MBBs.size();
+  if (NumEntries <= 32) {
+    return DAG.getNode(XCoreISD::BR_JT, dl, MVT::Other, Chain, TargetJT, Index);
+  }
+  assert((NumEntries >> 31) == 0);
+  SDValue ScaledIndex = DAG.getNode(ISD::SHL, dl, MVT::i32, Index,
+                                    DAG.getConstant(1, dl, MVT::i32));
+  return DAG.getNode(XCoreISD::BR_JT32, dl, MVT::Other, Chain, TargetJT,
+                     ScaledIndex);
+}
+
+SDValue XCoreTargetLowering::
+lowerLoadWordFromAlignedBasePlusOffset(SDLoc DL, SDValue Chain, SDValue Base,
+                                       int64_t Offset, SelectionDAG &DAG) const
+{
+  auto PtrVT = getPointerTy(DAG.getDataLayout());
+  if ((Offset & 0x3) == 0) {
+    return DAG.getLoad(PtrVT, DL, Chain, Base, MachinePointerInfo(), false,
+                       false, false, 0);
+  }
+  // Lower to pair of consecutive word aligned loads plus some bit shifting.
+  int32_t HighOffset = RoundUpToAlignment(Offset, 4);
+  int32_t LowOffset = HighOffset - 4;
+  SDValue LowAddr, HighAddr;
+  if (GlobalAddressSDNode *GASD =
+        dyn_cast<GlobalAddressSDNode>(Base.getNode())) {
+    LowAddr = DAG.getGlobalAddress(GASD->getGlobal(), DL, Base.getValueType(),
+                                   LowOffset);
+    HighAddr = DAG.getGlobalAddress(GASD->getGlobal(), DL, Base.getValueType(),
+                                    HighOffset);
+  } else {
+    LowAddr = DAG.getNode(ISD::ADD, DL, MVT::i32, Base,
+                          DAG.getConstant(LowOffset, DL, MVT::i32));
+    HighAddr = DAG.getNode(ISD::ADD, DL, MVT::i32, Base,
+                           DAG.getConstant(HighOffset, DL, MVT::i32));
+  }
+  SDValue LowShift = DAG.getConstant((Offset - LowOffset) * 8, DL, MVT::i32);
+  SDValue HighShift = DAG.getConstant((HighOffset - Offset) * 8, DL, MVT::i32);
+
+  SDValue Low = DAG.getLoad(PtrVT, DL, Chain, LowAddr, MachinePointerInfo(),
+                            false, false, false, 0);
+  SDValue High = DAG.getLoad(PtrVT, DL, Chain, HighAddr, MachinePointerInfo(),
+                             false, false, false, 0);
+  SDValue LowShifted = DAG.getNode(ISD::SRL, DL, MVT::i32, Low, LowShift);
+  SDValue HighShifted = DAG.getNode(ISD::SHL, DL, MVT::i32, High, HighShift);
+  SDValue Result = DAG.getNode(ISD::OR, DL, MVT::i32, LowShifted, HighShifted);
+  Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Low.getValue(1),
+                      High.getValue(1));
+  SDValue Ops[] = { Result, Chain };
+  return DAG.getMergeValues(Ops, DL);
+}
+
+static bool isWordAligned(SDValue Value, SelectionDAG &DAG)
+{
+  APInt KnownZero, KnownOne;
+  DAG.computeKnownBits(Value, KnownZero, KnownOne);
+  return KnownZero.countTrailingOnes() >= 2;
+}
+
+SDValue XCoreTargetLowering::
+LowerLOAD(SDValue Op, SelectionDAG &DAG) const {
+  const TargetLowering &TLI = DAG.getTargetLoweringInfo();
+  LoadSDNode *LD = cast<LoadSDNode>(Op);
+  assert(LD->getExtensionType() == ISD::NON_EXTLOAD &&
+         "Unexpected extension type");
+  assert(LD->getMemoryVT() == MVT::i32 && "Unexpected load EVT");
+  if (allowsMisalignedMemoryAccesses(LD->getMemoryVT(),
+                                     LD->getAddressSpace(),
+                                     LD->getAlignment()))
+    return SDValue();
+
+  auto &TD = DAG.getDataLayout();
+  unsigned ABIAlignment = TD.getABITypeAlignment(
+      LD->getMemoryVT().getTypeForEVT(*DAG.getContext()));
+  // Leave aligned load alone.
+  if (LD->getAlignment() >= ABIAlignment)
+    return SDValue();
+
+  SDValue Chain = LD->getChain();
+  SDValue BasePtr = LD->getBasePtr();
+  SDLoc DL(Op);
+
+  if (!LD->isVolatile()) {
+    const GlobalValue *GV;
+    int64_t Offset = 0;
+    if (DAG.isBaseWithConstantOffset(BasePtr) &&
+        isWordAligned(BasePtr->getOperand(0), DAG)) {
+      SDValue NewBasePtr = BasePtr->getOperand(0);
+      Offset = cast<ConstantSDNode>(BasePtr->getOperand(1))->getSExtValue();
+      return lowerLoadWordFromAlignedBasePlusOffset(DL, Chain, NewBasePtr,
+                                                    Offset, DAG);
+    }
+    if (TLI.isGAPlusOffset(BasePtr.getNode(), GV, Offset) &&
+        MinAlign(GV->getAlignment(), 4) == 4) {
+      SDValue NewBasePtr = DAG.getGlobalAddress(GV, DL,
+                                                BasePtr->getValueType(0));
+      return lowerLoadWordFromAlignedBasePlusOffset(DL, Chain, NewBasePtr,
+                                                    Offset, DAG);
+    }
+  }
+
+  if (LD->getAlignment() == 2) {
+    SDValue Low = DAG.getExtLoad(ISD::ZEXTLOAD, DL, MVT::i32, Chain,
+                                 BasePtr, LD->getPointerInfo(), MVT::i16,
+                                 LD->isVolatile(), LD->isNonTemporal(),
+                                 LD->isInvariant(), 2);
+    SDValue HighAddr = DAG.getNode(ISD::ADD, DL, MVT::i32, BasePtr,
+                                   DAG.getConstant(2, DL, MVT::i32));
+    SDValue High = DAG.getExtLoad(ISD::EXTLOAD, DL, MVT::i32, Chain,
+                                  HighAddr,
+                                  LD->getPointerInfo().getWithOffset(2),
+                                  MVT::i16, LD->isVolatile(),
+                                  LD->isNonTemporal(), LD->isInvariant(), 2);
+    SDValue HighShifted = DAG.getNode(ISD::SHL, DL, MVT::i32, High,
+                                      DAG.getConstant(16, DL, MVT::i32));
+    SDValue Result = DAG.getNode(ISD::OR, DL, MVT::i32, Low, HighShifted);
+    Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Low.getValue(1),
+                             High.getValue(1));
+    SDValue Ops[] = { Result, Chain };
+    return DAG.getMergeValues(Ops, DL);
+  }
+
+  // Lower to a call to __misaligned_load(BasePtr).
+  Type *IntPtrTy = TD.getIntPtrType(*DAG.getContext());
+  TargetLowering::ArgListTy Args;
+  TargetLowering::ArgListEntry Entry;
+
+  Entry.Ty = IntPtrTy;
+  Entry.Node = BasePtr;
+  Args.push_back(Entry);
+
+  TargetLowering::CallLoweringInfo CLI(DAG);
+  CLI.setDebugLoc(DL).setChain(Chain).setCallee(
+      CallingConv::C, IntPtrTy,
+      DAG.getExternalSymbol("__misaligned_load",
+                            getPointerTy(DAG.getDataLayout())),
+      std::move(Args), 0);
+
+  std::pair<SDValue, SDValue> CallResult = LowerCallTo(CLI);
+  SDValue Ops[] = { CallResult.first, CallResult.second };
+  return DAG.getMergeValues(Ops, DL);
+}
+
+SDValue XCoreTargetLowering::
+LowerSTORE(SDValue Op, SelectionDAG &DAG) const
+{
+  StoreSDNode *ST = cast<StoreSDNode>(Op);
+  assert(!ST->isTruncatingStore() && "Unexpected store type");
+  assert(ST->getMemoryVT() == MVT::i32 && "Unexpected store EVT");
+  if (allowsMisalignedMemoryAccesses(ST->getMemoryVT(),
+                                     ST->getAddressSpace(),
+                                     ST->getAlignment())) {
+    return SDValue();
+  }
+  unsigned ABIAlignment = DAG.getDataLayout().getABITypeAlignment(
+      ST->getMemoryVT().getTypeForEVT(*DAG.getContext()));
+  // Leave aligned store alone.
+  if (ST->getAlignment() >= ABIAlignment) {
+    return SDValue();
+  }
+  SDValue Chain = ST->getChain();
+  SDValue BasePtr = ST->getBasePtr();
+  SDValue Value = ST->getValue();
+  SDLoc dl(Op);
+
+  if (ST->getAlignment() == 2) {
+    SDValue Low = Value;
+    SDValue High = DAG.getNode(ISD::SRL, dl, MVT::i32, Value,
+                                      DAG.getConstant(16, dl, MVT::i32));
+    SDValue StoreLow = DAG.getTruncStore(Chain, dl, Low, BasePtr,
+                                         ST->getPointerInfo(), MVT::i16,
+                                         ST->isVolatile(), ST->isNonTemporal(),
+                                         2);
+    SDValue HighAddr = DAG.getNode(ISD::ADD, dl, MVT::i32, BasePtr,
+                                   DAG.getConstant(2, dl, MVT::i32));
+    SDValue StoreHigh = DAG.getTruncStore(Chain, dl, High, HighAddr,
+                                          ST->getPointerInfo().getWithOffset(2),
+                                          MVT::i16, ST->isVolatile(),
+                                          ST->isNonTemporal(), 2);
+    return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, StoreLow, StoreHigh);
+  }
+
+  // Lower to a call to __misaligned_store(BasePtr, Value).
+  Type *IntPtrTy = DAG.getDataLayout().getIntPtrType(*DAG.getContext());
+  TargetLowering::ArgListTy Args;
+  TargetLowering::ArgListEntry Entry;
+
+  Entry.Ty = IntPtrTy;
+  Entry.Node = BasePtr;
+  Args.push_back(Entry);
+
+  Entry.Node = Value;
+  Args.push_back(Entry);
+
+  TargetLowering::CallLoweringInfo CLI(DAG);
+  CLI.setDebugLoc(dl).setChain(Chain).setCallee(
+      CallingConv::C, Type::getVoidTy(*DAG.getContext()),
+      DAG.getExternalSymbol("__misaligned_store",
+                            getPointerTy(DAG.getDataLayout())),
+      std::move(Args), 0);
+
+  std::pair<SDValue, SDValue> CallResult = LowerCallTo(CLI);
+  return CallResult.second;
+}
+
+SDValue XCoreTargetLowering::
+LowerSMUL_LOHI(SDValue Op, SelectionDAG &DAG) const
+{
+  assert(Op.getValueType() == MVT::i32 && Op.getOpcode() == ISD::SMUL_LOHI &&
+         "Unexpected operand to lower!");
+  SDLoc dl(Op);
+  SDValue LHS = Op.getOperand(0);
+  SDValue RHS = Op.getOperand(1);
+  SDValue Zero = DAG.getConstant(0, dl, MVT::i32);
+  SDValue Hi = DAG.getNode(XCoreISD::MACCS, dl,
+                           DAG.getVTList(MVT::i32, MVT::i32), Zero, Zero,
+                           LHS, RHS);
+  SDValue Lo(Hi.getNode(), 1);
+  SDValue Ops[] = { Lo, Hi };
+  return DAG.getMergeValues(Ops, dl);
+}
+
+SDValue XCoreTargetLowering::
+LowerUMUL_LOHI(SDValue Op, SelectionDAG &DAG) const
+{
+  assert(Op.getValueType() == MVT::i32 && Op.getOpcode() == ISD::UMUL_LOHI &&
+         "Unexpected operand to lower!");
+  SDLoc dl(Op);
+  SDValue LHS = Op.getOperand(0);
+  SDValue RHS = Op.getOperand(1);
+  SDValue Zero = DAG.getConstant(0, dl, MVT::i32);
+  SDValue Hi = DAG.getNode(XCoreISD::LMUL, dl,
+                           DAG.getVTList(MVT::i32, MVT::i32), LHS, RHS,
+                           Zero, Zero);
+  SDValue Lo(Hi.getNode(), 1);
+  SDValue Ops[] = { Lo, Hi };
+  return DAG.getMergeValues(Ops, dl);
+}
+
+/// isADDADDMUL - Return whether Op is in a form that is equivalent to
+/// add(add(mul(x,y),a),b). If requireIntermediatesHaveOneUse is true then
+/// each intermediate result in the calculation must also have a single use.
+/// If the Op is in the correct form the constituent parts are written to Mul0,
+/// Mul1, Addend0 and Addend1.
+static bool
+isADDADDMUL(SDValue Op, SDValue &Mul0, SDValue &Mul1, SDValue &Addend0,
+            SDValue &Addend1, bool requireIntermediatesHaveOneUse)
+{
+  if (Op.getOpcode() != ISD::ADD)
+    return false;
+  SDValue N0 = Op.getOperand(0);
+  SDValue N1 = Op.getOperand(1);
+  SDValue AddOp;
+  SDValue OtherOp;
+  if (N0.getOpcode() == ISD::ADD) {
+    AddOp = N0;
+    OtherOp = N1;
+  } else if (N1.getOpcode() == ISD::ADD) {
+    AddOp = N1;
+    OtherOp = N0;
+  } else {
+    return false;
+  }
+  if (requireIntermediatesHaveOneUse && !AddOp.hasOneUse())
+    return false;
+  if (OtherOp.getOpcode() == ISD::MUL) {
+    // add(add(a,b),mul(x,y))
+    if (requireIntermediatesHaveOneUse && !OtherOp.hasOneUse())
+      return false;
+    Mul0 = OtherOp.getOperand(0);
+    Mul1 = OtherOp.getOperand(1);
+    Addend0 = AddOp.getOperand(0);
+    Addend1 = AddOp.getOperand(1);
+    return true;
+  }
+  if (AddOp.getOperand(0).getOpcode() == ISD::MUL) {
+    // add(add(mul(x,y),a),b)
+    if (requireIntermediatesHaveOneUse && !AddOp.getOperand(0).hasOneUse())
+      return false;
+    Mul0 = AddOp.getOperand(0).getOperand(0);
+    Mul1 = AddOp.getOperand(0).getOperand(1);
+    Addend0 = AddOp.getOperand(1);
+    Addend1 = OtherOp;
+    return true;
+  }
+  if (AddOp.getOperand(1).getOpcode() == ISD::MUL) {
+    // add(add(a,mul(x,y)),b)
+    if (requireIntermediatesHaveOneUse && !AddOp.getOperand(1).hasOneUse())
+      return false;
+    Mul0 = AddOp.getOperand(1).getOperand(0);
+    Mul1 = AddOp.getOperand(1).getOperand(1);
+    Addend0 = AddOp.getOperand(0);
+    Addend1 = OtherOp;
+    return true;
+  }
+  return false;
+}
+
+SDValue XCoreTargetLowering::
+TryExpandADDWithMul(SDNode *N, SelectionDAG &DAG) const
+{
+  SDValue Mul;
+  SDValue Other;
+  if (N->getOperand(0).getOpcode() == ISD::MUL) {
+    Mul = N->getOperand(0);
+    Other = N->getOperand(1);
+  } else if (N->getOperand(1).getOpcode() == ISD::MUL) {
+    Mul = N->getOperand(1);
+    Other = N->getOperand(0);
+  } else {
+    return SDValue();
+  }
+  SDLoc dl(N);
+  SDValue LL, RL, AddendL, AddendH;
+  LL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
+                   Mul.getOperand(0), DAG.getConstant(0, dl, MVT::i32));
+  RL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
+                   Mul.getOperand(1), DAG.getConstant(0, dl, MVT::i32));
+  AddendL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
+                        Other, DAG.getConstant(0, dl, MVT::i32));
+  AddendH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
+                        Other, DAG.getConstant(1, dl, MVT::i32));
+  APInt HighMask = APInt::getHighBitsSet(64, 32);
+  unsigned LHSSB = DAG.ComputeNumSignBits(Mul.getOperand(0));
+  unsigned RHSSB = DAG.ComputeNumSignBits(Mul.getOperand(1));
+  if (DAG.MaskedValueIsZero(Mul.getOperand(0), HighMask) &&
+      DAG.MaskedValueIsZero(Mul.getOperand(1), HighMask)) {
+    // The inputs are both zero-extended.
+    SDValue Hi = DAG.getNode(XCoreISD::MACCU, dl,
+                             DAG.getVTList(MVT::i32, MVT::i32), AddendH,
+                             AddendL, LL, RL);
+    SDValue Lo(Hi.getNode(), 1);
+    return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
+  }
+  if (LHSSB > 32 && RHSSB > 32) {
+    // The inputs are both sign-extended.
+    SDValue Hi = DAG.getNode(XCoreISD::MACCS, dl,
+                             DAG.getVTList(MVT::i32, MVT::i32), AddendH,
+                             AddendL, LL, RL);
+    SDValue Lo(Hi.getNode(), 1);
+    return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
+  }
+  SDValue LH, RH;
+  LH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
+                   Mul.getOperand(0), DAG.getConstant(1, dl, MVT::i32));
+  RH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
+                   Mul.getOperand(1), DAG.getConstant(1, dl, MVT::i32));
+  SDValue Hi = DAG.getNode(XCoreISD::MACCU, dl,
+                           DAG.getVTList(MVT::i32, MVT::i32), AddendH,
+                           AddendL, LL, RL);
+  SDValue Lo(Hi.getNode(), 1);
+  RH = DAG.getNode(ISD::MUL, dl, MVT::i32, LL, RH);
+  LH = DAG.getNode(ISD::MUL, dl, MVT::i32, LH, RL);
+  Hi = DAG.getNode(ISD::ADD, dl, MVT::i32, Hi, RH);
+  Hi = DAG.getNode(ISD::ADD, dl, MVT::i32, Hi, LH);
+  return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
+}
+
+SDValue XCoreTargetLowering::
+ExpandADDSUB(SDNode *N, SelectionDAG &DAG) const
+{
+  assert(N->getValueType(0) == MVT::i64 &&
+         (N->getOpcode() == ISD::ADD || N->getOpcode() == ISD::SUB) &&
+        "Unknown operand to lower!");
+
+  if (N->getOpcode() == ISD::ADD) {
+    SDValue Result = TryExpandADDWithMul(N, DAG);
+    if (Result.getNode())
+      return Result;
+  }
+
+  SDLoc dl(N);
+
+  // Extract components
+  SDValue LHSL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
+                             N->getOperand(0),
+                             DAG.getConstant(0, dl, MVT::i32));
+  SDValue LHSH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
+                             N->getOperand(0),
+                             DAG.getConstant(1, dl, MVT::i32));
+  SDValue RHSL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
+                             N->getOperand(1),
+                             DAG.getConstant(0, dl, MVT::i32));
+  SDValue RHSH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
+                             N->getOperand(1),
+                             DAG.getConstant(1, dl, MVT::i32));
+
+  // Expand
+  unsigned Opcode = (N->getOpcode() == ISD::ADD) ? XCoreISD::LADD :
+                                                   XCoreISD::LSUB;
+  SDValue Zero = DAG.getConstant(0, dl, MVT::i32);
+  SDValue Lo = DAG.getNode(Opcode, dl, DAG.getVTList(MVT::i32, MVT::i32),
+                           LHSL, RHSL, Zero);
+  SDValue Carry(Lo.getNode(), 1);
+
+  SDValue Hi = DAG.getNode(Opcode, dl, DAG.getVTList(MVT::i32, MVT::i32),
+                           LHSH, RHSH, Carry);
+  SDValue Ignored(Hi.getNode(), 1);
+  // Merge the pieces
+  return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
+}
+
+SDValue XCoreTargetLowering::
+LowerVAARG(SDValue Op, SelectionDAG &DAG) const
+{
+  // Whist llvm does not support aggregate varargs we can ignore
+  // the possibility of the ValueType being an implicit byVal vararg.
+  SDNode *Node = Op.getNode();
+  EVT VT = Node->getValueType(0); // not an aggregate
+  SDValue InChain = Node->getOperand(0);
+  SDValue VAListPtr = Node->getOperand(1);
+  EVT PtrVT = VAListPtr.getValueType();
+  const Value *SV = cast<SrcValueSDNode>(Node->getOperand(2))->getValue();
+  SDLoc dl(Node);
+  SDValue VAList = DAG.getLoad(PtrVT, dl, InChain,
+                               VAListPtr, MachinePointerInfo(SV),
+                               false, false, false, 0);
+  // Increment the pointer, VAList, to the next vararg
+  SDValue nextPtr = DAG.getNode(ISD::ADD, dl, PtrVT, VAList,
+                                DAG.getIntPtrConstant(VT.getSizeInBits() / 8,
+                                                      dl));
+  // Store the incremented VAList to the legalized pointer
+  InChain = DAG.getStore(VAList.getValue(1), dl, nextPtr, VAListPtr,
+                         MachinePointerInfo(SV), false, false, 0);
+  // Load the actual argument out of the pointer VAList
+  return DAG.getLoad(VT, dl, InChain, VAList, MachinePointerInfo(),
+                     false, false, false, 0);
+}
+
+SDValue XCoreTargetLowering::
+LowerVASTART(SDValue Op, SelectionDAG &DAG) const
+{
+  SDLoc dl(Op);
+  // vastart stores the address of the VarArgsFrameIndex slot into the
+  // memory location argument
+  MachineFunction &MF = DAG.getMachineFunction();
+  XCoreFunctionInfo *XFI = MF.getInfo<XCoreFunctionInfo>();
+  SDValue Addr = DAG.getFrameIndex(XFI->getVarArgsFrameIndex(), MVT::i32);
+  return DAG.getStore(Op.getOperand(0), dl, Addr, Op.getOperand(1),
+                      MachinePointerInfo(), false, false, 0);
+}
+
+SDValue XCoreTargetLowering::LowerFRAMEADDR(SDValue Op,
+                                            SelectionDAG &DAG) const {
+  // This nodes represent llvm.frameaddress on the DAG.
+  // It takes one operand, the index of the frame address to return.
+  // An index of zero corresponds to the current function's frame address.
+  // An index of one to the parent's frame address, and so on.
+  // Depths > 0 not supported yet!
+  if (cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() > 0)
+    return SDValue();
+
+  MachineFunction &MF = DAG.getMachineFunction();
+  const TargetRegisterInfo *RegInfo = Subtarget.getRegisterInfo();
+  return DAG.getCopyFromReg(DAG.getEntryNode(), SDLoc(Op),
+                            RegInfo->getFrameRegister(MF), MVT::i32);
+}
+
+SDValue XCoreTargetLowering::
+LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const {
+  // This nodes represent llvm.returnaddress on the DAG.
+  // It takes one operand, the index of the return address to return.
+  // An index of zero corresponds to the current function's return address.
+  // An index of one to the parent's return address, and so on.
+  // Depths > 0 not supported yet!
+  if (cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() > 0)
+    return SDValue();
+
+  MachineFunction &MF = DAG.getMachineFunction();
+  XCoreFunctionInfo *XFI = MF.getInfo<XCoreFunctionInfo>();
+  int FI = XFI->createLRSpillSlot(MF);
+  SDValue FIN = DAG.getFrameIndex(FI, MVT::i32);
+  return DAG.getLoad(
+      getPointerTy(DAG.getDataLayout()), SDLoc(Op), DAG.getEntryNode(), FIN,
+      MachinePointerInfo::getFixedStack(MF, FI), false, false, false, 0);
+}
+
+SDValue XCoreTargetLowering::
+LowerFRAME_TO_ARGS_OFFSET(SDValue Op, SelectionDAG &DAG) const {
+  // This node represents offset from frame pointer to first on-stack argument.
+  // This is needed for correct stack adjustment during unwind.
+  // However, we don't know the offset until after the frame has be finalised.
+  // This is done during the XCoreFTAOElim pass.
+  return DAG.getNode(XCoreISD::FRAME_TO_ARGS_OFFSET, SDLoc(Op), MVT::i32);
+}
+
+SDValue XCoreTargetLowering::
+LowerEH_RETURN(SDValue Op, SelectionDAG &DAG) const {
+  // OUTCHAIN = EH_RETURN(INCHAIN, OFFSET, HANDLER)
+  // This node represents 'eh_return' gcc dwarf builtin, which is used to
+  // return from exception. The general meaning is: adjust stack by OFFSET and
+  // pass execution to HANDLER.
+  MachineFunction &MF = DAG.getMachineFunction();
+  SDValue Chain     = Op.getOperand(0);
+  SDValue Offset    = Op.getOperand(1);
+  SDValue Handler   = Op.getOperand(2);
+  SDLoc dl(Op);
+
+  // Absolute SP = (FP + FrameToArgs) + Offset
+  const TargetRegisterInfo *RegInfo = Subtarget.getRegisterInfo();
+  SDValue Stack = DAG.getCopyFromReg(DAG.getEntryNode(), dl,
+                            RegInfo->getFrameRegister(MF), MVT::i32);
+  SDValue FrameToArgs = DAG.getNode(XCoreISD::FRAME_TO_ARGS_OFFSET, dl,
+                                    MVT::i32);
+  Stack = DAG.getNode(ISD::ADD, dl, MVT::i32, Stack, FrameToArgs);
+  Stack = DAG.getNode(ISD::ADD, dl, MVT::i32, Stack, Offset);
+
+  // R0=ExceptionPointerRegister R1=ExceptionSelectorRegister
+  // which leaves 2 caller saved registers, R2 & R3 for us to use.
+  unsigned StackReg = XCore::R2;
+  unsigned HandlerReg = XCore::R3;
+
+  SDValue OutChains[] = {
+    DAG.getCopyToReg(Chain, dl, StackReg, Stack),
+    DAG.getCopyToReg(Chain, dl, HandlerReg, Handler)
+  };
+
+  Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, OutChains);
+
+  return DAG.getNode(XCoreISD::EH_RETURN, dl, MVT::Other, Chain,
+                     DAG.getRegister(StackReg, MVT::i32),
+                     DAG.getRegister(HandlerReg, MVT::i32));
+
+}
+
+SDValue XCoreTargetLowering::
+LowerADJUST_TRAMPOLINE(SDValue Op, SelectionDAG &DAG) const {
+  return Op.getOperand(0);
+}
+
+SDValue XCoreTargetLowering::
+LowerINIT_TRAMPOLINE(SDValue Op, SelectionDAG &DAG) const {
+  SDValue Chain = Op.getOperand(0);
+  SDValue Trmp = Op.getOperand(1); // trampoline
+  SDValue FPtr = Op.getOperand(2); // nested function
+  SDValue Nest = Op.getOperand(3); // 'nest' parameter value
+
+  const Value *TrmpAddr = cast<SrcValueSDNode>(Op.getOperand(4))->getValue();
+
+  // .align 4
+  // LDAPF_u10 r11, nest
+  // LDW_2rus r11, r11[0]
+  // STWSP_ru6 r11, sp[0]
+  // LDAPF_u10 r11, fptr
+  // LDW_2rus r11, r11[0]
+  // BAU_1r r11
+  // nest:
+  // .word nest
+  // fptr:
+  // .word fptr
+  SDValue OutChains[5];
+
+  SDValue Addr = Trmp;
+
+  SDLoc dl(Op);
+  OutChains[0] = DAG.getStore(Chain, dl,
+                              DAG.getConstant(0x0a3cd805, dl, MVT::i32), Addr,
+                              MachinePointerInfo(TrmpAddr), false, false, 0);
+
+  Addr = DAG.getNode(ISD::ADD, dl, MVT::i32, Trmp,
+                     DAG.getConstant(4, dl, MVT::i32));
+  OutChains[1] = DAG.getStore(Chain, dl,
+                              DAG.getConstant(0xd80456c0, dl, MVT::i32), Addr,
+                              MachinePointerInfo(TrmpAddr, 4), false, false, 0);
+
+  Addr = DAG.getNode(ISD::ADD, dl, MVT::i32, Trmp,
+                     DAG.getConstant(8, dl, MVT::i32));
+  OutChains[2] = DAG.getStore(Chain, dl,
+                              DAG.getConstant(0x27fb0a3c, dl, MVT::i32), Addr,
+                              MachinePointerInfo(TrmpAddr, 8), false, false, 0);
+
+  Addr = DAG.getNode(ISD::ADD, dl, MVT::i32, Trmp,
+                     DAG.getConstant(12, dl, MVT::i32));
+  OutChains[3] = DAG.getStore(Chain, dl, Nest, Addr,
+                              MachinePointerInfo(TrmpAddr, 12), false, false,
+                              0);
+
+  Addr = DAG.getNode(ISD::ADD, dl, MVT::i32, Trmp,
+                     DAG.getConstant(16, dl, MVT::i32));
+  OutChains[4] = DAG.getStore(Chain, dl, FPtr, Addr,
+                              MachinePointerInfo(TrmpAddr, 16), false, false,
+                              0);
+
+  return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, OutChains);
+}
+
+SDValue XCoreTargetLowering::
+LowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG) const {
+  SDLoc DL(Op);
+  unsigned IntNo = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
+  switch (IntNo) {
+    case Intrinsic::xcore_crc8:
+      EVT VT = Op.getValueType();
+      SDValue Data =
+        DAG.getNode(XCoreISD::CRC8, DL, DAG.getVTList(VT, VT),
+                    Op.getOperand(1), Op.getOperand(2) , Op.getOperand(3));
+      SDValue Crc(Data.getNode(), 1);
+      SDValue Results[] = { Crc, Data };
+      return DAG.getMergeValues(Results, DL);
+  }
+  return SDValue();
+}
+
+SDValue XCoreTargetLowering::
+LowerATOMIC_FENCE(SDValue Op, SelectionDAG &DAG) const {
+  SDLoc DL(Op);
+  return DAG.getNode(XCoreISD::MEMBARRIER, DL, MVT::Other, Op.getOperand(0));
+}
+
+SDValue XCoreTargetLowering::
+LowerATOMIC_LOAD(SDValue Op, SelectionDAG &DAG) const {
+  AtomicSDNode *N = cast<AtomicSDNode>(Op);
+  assert(N->getOpcode() == ISD::ATOMIC_LOAD && "Bad Atomic OP");
+  assert(N->getOrdering() <= Monotonic &&
+         "setInsertFencesForAtomic(true) and yet greater than Monotonic");
+  if (N->getMemoryVT() == MVT::i32) {
+    if (N->getAlignment() < 4)
+      report_fatal_error("atomic load must be aligned");
+    return DAG.getLoad(getPointerTy(DAG.getDataLayout()), SDLoc(Op),
+                       N->getChain(), N->getBasePtr(), N->getPointerInfo(),
+                       N->isVolatile(), N->isNonTemporal(), N->isInvariant(),
+                       N->getAlignment(), N->getAAInfo(), N->getRanges());
+  }
+  if (N->getMemoryVT() == MVT::i16) {
+    if (N->getAlignment() < 2)
+      report_fatal_error("atomic load must be aligned");
+    return DAG.getExtLoad(ISD::EXTLOAD, SDLoc(Op), MVT::i32, N->getChain(),
+                          N->getBasePtr(), N->getPointerInfo(), MVT::i16,
+                          N->isVolatile(), N->isNonTemporal(),
+                          N->isInvariant(), N->getAlignment(), N->getAAInfo());
+  }
+  if (N->getMemoryVT() == MVT::i8)
+    return DAG.getExtLoad(ISD::EXTLOAD, SDLoc(Op), MVT::i32, N->getChain(),
+                          N->getBasePtr(), N->getPointerInfo(), MVT::i8,
+                          N->isVolatile(), N->isNonTemporal(),
+                          N->isInvariant(), N->getAlignment(), N->getAAInfo());
+  return SDValue();
+}
+
+SDValue XCoreTargetLowering::
+LowerATOMIC_STORE(SDValue Op, SelectionDAG &DAG) const {
+  AtomicSDNode *N = cast<AtomicSDNode>(Op);
+  assert(N->getOpcode() == ISD::ATOMIC_STORE && "Bad Atomic OP");
+  assert(N->getOrdering() <= Monotonic &&
+         "setInsertFencesForAtomic(true) and yet greater than Monotonic");
+  if (N->getMemoryVT() == MVT::i32) {
+    if (N->getAlignment() < 4)
+      report_fatal_error("atomic store must be aligned");
+    return DAG.getStore(N->getChain(), SDLoc(Op), N->getVal(),
+                        N->getBasePtr(), N->getPointerInfo(),
+                        N->isVolatile(), N->isNonTemporal(),
+                        N->getAlignment(), N->getAAInfo());
+  }
+  if (N->getMemoryVT() == MVT::i16) {
+    if (N->getAlignment() < 2)
+      report_fatal_error("atomic store must be aligned");
+    return DAG.getTruncStore(N->getChain(), SDLoc(Op), N->getVal(),
+                             N->getBasePtr(), N->getPointerInfo(), MVT::i16,
+                             N->isVolatile(), N->isNonTemporal(),
+                             N->getAlignment(), N->getAAInfo());
+  }
+  if (N->getMemoryVT() == MVT::i8)
+    return DAG.getTruncStore(N->getChain(), SDLoc(Op), N->getVal(),
+                             N->getBasePtr(), N->getPointerInfo(), MVT::i8,
+                             N->isVolatile(), N->isNonTemporal(),
+                             N->getAlignment(), N->getAAInfo());
+  return SDValue();
+}
+
+//===----------------------------------------------------------------------===//
+//                      Calling Convention Implementation
+//===----------------------------------------------------------------------===//
+
+#include "XCoreGenCallingConv.inc"
+
+//===----------------------------------------------------------------------===//
+//                  Call Calling Convention Implementation
+//===----------------------------------------------------------------------===//
+
+/// XCore call implementation
+SDValue
+XCoreTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
+                               SmallVectorImpl<SDValue> &InVals) const {
+  SelectionDAG &DAG                     = CLI.DAG;
+  SDLoc &dl                             = CLI.DL;
+  SmallVectorImpl<ISD::OutputArg> &Outs = CLI.Outs;
+  SmallVectorImpl<SDValue> &OutVals     = CLI.OutVals;
+  SmallVectorImpl<ISD::InputArg> &Ins   = CLI.Ins;
+  SDValue Chain                         = CLI.Chain;
+  SDValue Callee                        = CLI.Callee;
+  bool &isTailCall                      = CLI.IsTailCall;
+  CallingConv::ID CallConv              = CLI.CallConv;
+  bool isVarArg                         = CLI.IsVarArg;
+
+  // XCore target does not yet support tail call optimization.
+  isTailCall = false;
+
+  // For now, only CallingConv::C implemented
+  switch (CallConv)
+  {
+    default:
+      llvm_unreachable("Unsupported calling convention");
+    case CallingConv::Fast:
+    case CallingConv::C:
+      return LowerCCCCallTo(Chain, Callee, CallConv, isVarArg, isTailCall,
+                            Outs, OutVals, Ins, dl, DAG, InVals);
+  }
+}
+
+/// LowerCallResult - Lower the result values of a call into the
+/// appropriate copies out of appropriate physical registers / memory locations.
+static SDValue
+LowerCallResult(SDValue Chain, SDValue InFlag,
+                const SmallVectorImpl<CCValAssign> &RVLocs,
+                SDLoc dl, SelectionDAG &DAG,
+                SmallVectorImpl<SDValue> &InVals) {
+  SmallVector<std::pair<int, unsigned>, 4> ResultMemLocs;
+  // Copy results out of physical registers.
+  for (unsigned i = 0, e = RVLocs.size(); i != e; ++i) {
+    const CCValAssign &VA = RVLocs[i];
+    if (VA.isRegLoc()) {
+      Chain = DAG.getCopyFromReg(Chain, dl, VA.getLocReg(), VA.getValVT(),
+                                 InFlag).getValue(1);
+      InFlag = Chain.getValue(2);
+      InVals.push_back(Chain.getValue(0));
+    } else {
+      assert(VA.isMemLoc());
+      ResultMemLocs.push_back(std::make_pair(VA.getLocMemOffset(),
+                                             InVals.size()));
+      // Reserve space for this result.
+      InVals.push_back(SDValue());
+    }
+  }
+
+  // Copy results out of memory.
+  SmallVector<SDValue, 4> MemOpChains;
+  for (unsigned i = 0, e = ResultMemLocs.size(); i != e; ++i) {
+    int offset = ResultMemLocs[i].first;
+    unsigned index = ResultMemLocs[i].second;
+    SDVTList VTs = DAG.getVTList(MVT::i32, MVT::Other);
+    SDValue Ops[] = { Chain, DAG.getConstant(offset / 4, dl, MVT::i32) };
+    SDValue load = DAG.getNode(XCoreISD::LDWSP, dl, VTs, Ops);
+    InVals[index] = load;
+    MemOpChains.push_back(load.getValue(1));
+  }
+
+  // Transform all loads nodes into one single node because
+  // all load nodes are independent of each other.
+  if (!MemOpChains.empty())
+    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, MemOpChains);
+
+  return Chain;
+}
+
+/// LowerCCCCallTo - functions arguments are copied from virtual
+/// regs to (physical regs)/(stack frame), CALLSEQ_START and
+/// CALLSEQ_END are emitted.
+/// TODO: isTailCall, sret.
+SDValue
+XCoreTargetLowering::LowerCCCCallTo(SDValue Chain, SDValue Callee,
+                                    CallingConv::ID CallConv, bool isVarArg,
+                                    bool isTailCall,
+                                    const SmallVectorImpl<ISD::OutputArg> &Outs,
+                                    const SmallVectorImpl<SDValue> &OutVals,
+                                    const SmallVectorImpl<ISD::InputArg> &Ins,
+                                    SDLoc dl, SelectionDAG &DAG,
+                                    SmallVectorImpl<SDValue> &InVals) const {
+
+  // Analyze operands of the call, assigning locations to each operand.
+  SmallVector<CCValAssign, 16> ArgLocs;
+  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(), ArgLocs,
+                 *DAG.getContext());
+
+  // The ABI dictates there should be one stack slot available to the callee
+  // on function entry (for saving lr).
+  CCInfo.AllocateStack(4, 4);
+
+  CCInfo.AnalyzeCallOperands(Outs, CC_XCore);
+
+  SmallVector<CCValAssign, 16> RVLocs;
+  // Analyze return values to determine the number of bytes of stack required.
+  CCState RetCCInfo(CallConv, isVarArg, DAG.getMachineFunction(), RVLocs,
+                    *DAG.getContext());
+  RetCCInfo.AllocateStack(CCInfo.getNextStackOffset(), 4);
+  RetCCInfo.AnalyzeCallResult(Ins, RetCC_XCore);
+
+  // Get a count of how many bytes are to be pushed on the stack.
+  unsigned NumBytes = RetCCInfo.getNextStackOffset();
+  auto PtrVT = getPointerTy(DAG.getDataLayout());
+
+  Chain = DAG.getCALLSEQ_START(Chain,
+                               DAG.getConstant(NumBytes, dl, PtrVT, true), dl);
+
+  SmallVector<std::pair<unsigned, SDValue>, 4> RegsToPass;
+  SmallVector<SDValue, 12> MemOpChains;
+
+  // Walk the register/memloc assignments, inserting copies/loads.
+  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
+    CCValAssign &VA = ArgLocs[i];
+    SDValue Arg = OutVals[i];
+
+    // Promote the value if needed.
+    switch (VA.getLocInfo()) {
+      default: llvm_unreachable("Unknown loc info!");
+      case CCValAssign::Full: break;
+      case CCValAssign::SExt:
+        Arg = DAG.getNode(ISD::SIGN_EXTEND, dl, VA.getLocVT(), Arg);
+        break;
+      case CCValAssign::ZExt:
+        Arg = DAG.getNode(ISD::ZERO_EXTEND, dl, VA.getLocVT(), Arg);
+        break;
+      case CCValAssign::AExt:
+        Arg = DAG.getNode(ISD::ANY_EXTEND, dl, VA.getLocVT(), Arg);
+        break;
+    }
+
+    // Arguments that can be passed on register must be kept at
+    // RegsToPass vector
+    if (VA.isRegLoc()) {
+      RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
+    } else {
+      assert(VA.isMemLoc());
+
+      int Offset = VA.getLocMemOffset();
+
+      MemOpChains.push_back(DAG.getNode(XCoreISD::STWSP, dl, MVT::Other,
+                                        Chain, Arg,
+                                        DAG.getConstant(Offset/4, dl,
+                                                        MVT::i32)));
+    }
+  }
+
+  // Transform all store nodes into one single node because
+  // all store nodes are independent of each other.
+  if (!MemOpChains.empty())
+    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, MemOpChains);
+
+  // Build a sequence of copy-to-reg nodes chained together with token
+  // chain and flag operands which copy the outgoing args into registers.
+  // The InFlag in necessary since all emitted instructions must be
+  // stuck together.
+  SDValue InFlag;
+  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
+    Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first,
+                             RegsToPass[i].second, InFlag);
+    InFlag = Chain.getValue(1);
+  }
+
+  // If the callee is a GlobalAddress node (quite common, every direct call is)
+  // turn it into a TargetGlobalAddress node so that legalize doesn't hack it.
+  // Likewise ExternalSymbol -> TargetExternalSymbol.
+  if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
+    Callee = DAG.getTargetGlobalAddress(G->getGlobal(), dl, MVT::i32);
+  else if (ExternalSymbolSDNode *E = dyn_cast<ExternalSymbolSDNode>(Callee))
+    Callee = DAG.getTargetExternalSymbol(E->getSymbol(), MVT::i32);
+
+  // XCoreBranchLink = #chain, #target_address, #opt_in_flags...
+  //             = Chain, Callee, Reg#1, Reg#2, ...
+  //
+  // Returns a chain & a flag for retval copy to use.
+  SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
+  SmallVector<SDValue, 8> Ops;
+  Ops.push_back(Chain);
+  Ops.push_back(Callee);
+
+  // Add argument registers to the end of the list so that they are
+  // known live into the call.
+  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i)
+    Ops.push_back(DAG.getRegister(RegsToPass[i].first,
+                                  RegsToPass[i].second.getValueType()));
+
+  if (InFlag.getNode())
+    Ops.push_back(InFlag);
+
+  Chain  = DAG.getNode(XCoreISD::BL, dl, NodeTys, Ops);
+  InFlag = Chain.getValue(1);
+
+  // Create the CALLSEQ_END node.
+  Chain = DAG.getCALLSEQ_END(Chain, DAG.getConstant(NumBytes, dl, PtrVT, true),
+                             DAG.getConstant(0, dl, PtrVT, true), InFlag, dl);
+  InFlag = Chain.getValue(1);
+
+  // Handle result values, copying them out of physregs into vregs that we
+  // return.
+  return LowerCallResult(Chain, InFlag, RVLocs, dl, DAG, InVals);
+}
+
+//===----------------------------------------------------------------------===//
+//             Formal Arguments Calling Convention Implementation
+//===----------------------------------------------------------------------===//
+
+namespace {
+  struct ArgDataPair { SDValue SDV; ISD::ArgFlagsTy Flags; };
+}
+
+/// XCore formal arguments implementation
+SDValue
+XCoreTargetLowering::LowerFormalArguments(SDValue Chain,
+                                          CallingConv::ID CallConv,
+                                          bool isVarArg,
+                                      const SmallVectorImpl<ISD::InputArg> &Ins,
+                                          SDLoc dl,
+                                          SelectionDAG &DAG,
+                                          SmallVectorImpl<SDValue> &InVals)
+                                            const {
+  switch (CallConv)
+  {
+    default:
+      llvm_unreachable("Unsupported calling convention");
+    case CallingConv::C:
+    case CallingConv::Fast:
+      return LowerCCCArguments(Chain, CallConv, isVarArg,
+                               Ins, dl, DAG, InVals);
+  }
+}
+
+/// LowerCCCArguments - transform physical registers into
+/// virtual registers and generate load operations for
+/// arguments places on the stack.
+/// TODO: sret
+SDValue
+XCoreTargetLowering::LowerCCCArguments(SDValue Chain,
+                                       CallingConv::ID CallConv,
+                                       bool isVarArg,
+                                       const SmallVectorImpl<ISD::InputArg>
+                                         &Ins,
+                                       SDLoc dl,
+                                       SelectionDAG &DAG,
+                                       SmallVectorImpl<SDValue> &InVals) const {
+  MachineFunction &MF = DAG.getMachineFunction();
+  MachineFrameInfo *MFI = MF.getFrameInfo();
+  MachineRegisterInfo &RegInfo = MF.getRegInfo();
+  XCoreFunctionInfo *XFI = MF.getInfo<XCoreFunctionInfo>();
+
+  // Assign locations to all of the incoming arguments.
+  SmallVector<CCValAssign, 16> ArgLocs;
+  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(), ArgLocs,
+                 *DAG.getContext());
+
+  CCInfo.AnalyzeFormalArguments(Ins, CC_XCore);
+
+  unsigned StackSlotSize = XCoreFrameLowering::stackSlotSize();
+
+  unsigned LRSaveSize = StackSlotSize;
+
+  if (!isVarArg)
+    XFI->setReturnStackOffset(CCInfo.getNextStackOffset() + LRSaveSize);
+
+  // All getCopyFromReg ops must precede any getMemcpys to prevent the
+  // scheduler clobbering a register before it has been copied.
+  // The stages are:
+  // 1. CopyFromReg (and load) arg & vararg registers.
+  // 2. Chain CopyFromReg nodes into a TokenFactor.
+  // 3. Memcpy 'byVal' args & push final InVals.
+  // 4. Chain mem ops nodes into a TokenFactor.
+  SmallVector<SDValue, 4> CFRegNode;
+  SmallVector<ArgDataPair, 4> ArgData;
+  SmallVector<SDValue, 4> MemOps;
+
+  // 1a. CopyFromReg (and load) arg registers.
+  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
+
+    CCValAssign &VA = ArgLocs[i];
+    SDValue ArgIn;
+
+    if (VA.isRegLoc()) {
+      // Arguments passed in registers
+      EVT RegVT = VA.getLocVT();
+      switch (RegVT.getSimpleVT().SimpleTy) {
+      default:
+        {
+#ifndef NDEBUG
+          errs() << "LowerFormalArguments Unhandled argument type: "
+                 << RegVT.getSimpleVT().SimpleTy << "\n";
+#endif
+          llvm_unreachable(nullptr);
+        }
+      case MVT::i32:
+        unsigned VReg = RegInfo.createVirtualRegister(&XCore::GRRegsRegClass);
+        RegInfo.addLiveIn(VA.getLocReg(), VReg);
+        ArgIn = DAG.getCopyFromReg(Chain, dl, VReg, RegVT);
+        CFRegNode.push_back(ArgIn.getValue(ArgIn->getNumValues() - 1));
+      }
+    } else {
+      // sanity check
+      assert(VA.isMemLoc());
+      // Load the argument to a virtual register
+      unsigned ObjSize = VA.getLocVT().getSizeInBits()/8;
+      if (ObjSize > StackSlotSize) {
+        errs() << "LowerFormalArguments Unhandled argument type: "
+               << EVT(VA.getLocVT()).getEVTString()
+               << "\n";
+      }
+      // Create the frame index object for this incoming parameter...
+      int FI = MFI->CreateFixedObject(ObjSize,
+                                      LRSaveSize + VA.getLocMemOffset(),
+                                      true);
+
+      // Create the SelectionDAG nodes corresponding to a load
+      //from this parameter
+      SDValue FIN = DAG.getFrameIndex(FI, MVT::i32);
+      ArgIn = DAG.getLoad(VA.getLocVT(), dl, Chain, FIN,
+                          MachinePointerInfo::getFixedStack(MF, FI), false,
+                          false, false, 0);
+    }
+    const ArgDataPair ADP = { ArgIn, Ins[i].Flags };
+    ArgData.push_back(ADP);
+  }
+
+  // 1b. CopyFromReg vararg registers.
+  if (isVarArg) {
+    // Argument registers
+    static const MCPhysReg ArgRegs[] = {
+      XCore::R0, XCore::R1, XCore::R2, XCore::R3
+    };
+    XCoreFunctionInfo *XFI = MF.getInfo<XCoreFunctionInfo>();
+    unsigned FirstVAReg = CCInfo.getFirstUnallocated(ArgRegs);
+    if (FirstVAReg < array_lengthof(ArgRegs)) {
+      int offset = 0;
+      // Save remaining registers, storing higher register numbers at a higher
+      // address
+      for (int i = array_lengthof(ArgRegs) - 1; i >= (int)FirstVAReg; --i) {
+        // Create a stack slot
+        int FI = MFI->CreateFixedObject(4, offset, true);
+        if (i == (int)FirstVAReg) {
+          XFI->setVarArgsFrameIndex(FI);
+        }
+        offset -= StackSlotSize;
+        SDValue FIN = DAG.getFrameIndex(FI, MVT::i32);
+        // Move argument from phys reg -> virt reg
+        unsigned VReg = RegInfo.createVirtualRegister(&XCore::GRRegsRegClass);
+        RegInfo.addLiveIn(ArgRegs[i], VReg);
+        SDValue Val = DAG.getCopyFromReg(Chain, dl, VReg, MVT::i32);
+        CFRegNode.push_back(Val.getValue(Val->getNumValues() - 1));
+        // Move argument from virt reg -> stack
+        SDValue Store = DAG.getStore(Val.getValue(1), dl, Val, FIN,
+                                     MachinePointerInfo(), false, false, 0);
+        MemOps.push_back(Store);
+      }
+    } else {
+      // This will point to the next argument passed via stack.
+      XFI->setVarArgsFrameIndex(
+        MFI->CreateFixedObject(4, LRSaveSize + CCInfo.getNextStackOffset(),
+                               true));
+    }
+  }
+
+  // 2. chain CopyFromReg nodes into a TokenFactor.
+  if (!CFRegNode.empty())
+    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, CFRegNode);
+
+  // 3. Memcpy 'byVal' args & push final InVals.
+  // Aggregates passed "byVal" need to be copied by the callee.
+  // The callee will use a pointer to this copy, rather than the original
+  // pointer.
+  for (SmallVectorImpl<ArgDataPair>::const_iterator ArgDI = ArgData.begin(),
+                                                    ArgDE = ArgData.end();
+       ArgDI != ArgDE; ++ArgDI) {
+    if (ArgDI->Flags.isByVal() && ArgDI->Flags.getByValSize()) {
+      unsigned Size = ArgDI->Flags.getByValSize();
+      unsigned Align = std::max(StackSlotSize, ArgDI->Flags.getByValAlign());
+      // Create a new object on the stack and copy the pointee into it.
+      int FI = MFI->CreateStackObject(Size, Align, false);
+      SDValue FIN = DAG.getFrameIndex(FI, MVT::i32);
+      InVals.push_back(FIN);
+      MemOps.push_back(DAG.getMemcpy(Chain, dl, FIN, ArgDI->SDV,
+                                     DAG.getConstant(Size, dl, MVT::i32),
+                                     Align, false, false, false,
+                                     MachinePointerInfo(),
+                                     MachinePointerInfo()));
+    } else {
+      InVals.push_back(ArgDI->SDV);
+    }
+  }
+
+  // 4, chain mem ops nodes into a TokenFactor.
+  if (!MemOps.empty()) {
+    MemOps.push_back(Chain);
+    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, MemOps);
+  }
+
+  return Chain;
+}
+
+//===----------------------------------------------------------------------===//
+//               Return Value Calling Convention Implementation
+//===----------------------------------------------------------------------===//
+
+bool XCoreTargetLowering::
+CanLowerReturn(CallingConv::ID CallConv, MachineFunction &MF,
+               bool isVarArg,
+               const SmallVectorImpl<ISD::OutputArg> &Outs,
+               LLVMContext &Context) const {
+  SmallVector<CCValAssign, 16> RVLocs;
+  CCState CCInfo(CallConv, isVarArg, MF, RVLocs, Context);
+  if (!CCInfo.CheckReturn(Outs, RetCC_XCore))
+    return false;
+  if (CCInfo.getNextStackOffset() != 0 && isVarArg)
+    return false;
+  return true;
+}
+
+SDValue
+XCoreTargetLowering::LowerReturn(SDValue Chain,
+                                 CallingConv::ID CallConv, bool isVarArg,
+                                 const SmallVectorImpl<ISD::OutputArg> &Outs,
+                                 const SmallVectorImpl<SDValue> &OutVals,
+                                 SDLoc dl, SelectionDAG &DAG) const {
+
+  XCoreFunctionInfo *XFI =
+    DAG.getMachineFunction().getInfo<XCoreFunctionInfo>();
+  MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
+
+  // CCValAssign - represent the assignment of
+  // the return value to a location
+  SmallVector<CCValAssign, 16> RVLocs;
+
+  // CCState - Info about the registers and stack slot.
+  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(), RVLocs,
+                 *DAG.getContext());
+
+  // Analyze return values.
+  if (!isVarArg)
+    CCInfo.AllocateStack(XFI->getReturnStackOffset(), 4);
+
+  CCInfo.AnalyzeReturn(Outs, RetCC_XCore);
+
+  SDValue Flag;
+  SmallVector<SDValue, 4> RetOps(1, Chain);
+
+  // Return on XCore is always a "retsp 0"
+  RetOps.push_back(DAG.getConstant(0, dl, MVT::i32));
+
+  SmallVector<SDValue, 4> MemOpChains;
+  // Handle return values that must be copied to memory.
+  for (unsigned i = 0, e = RVLocs.size(); i != e; ++i) {
+    CCValAssign &VA = RVLocs[i];
+    if (VA.isRegLoc())
+      continue;
+    assert(VA.isMemLoc());
+    if (isVarArg) {
+      report_fatal_error("Can't return value from vararg function in memory");
+    }
+
+    int Offset = VA.getLocMemOffset();
+    unsigned ObjSize = VA.getLocVT().getSizeInBits() / 8;
+    // Create the frame index object for the memory location.
+    int FI = MFI->CreateFixedObject(ObjSize, Offset, false);
+
+    // Create a SelectionDAG node corresponding to a store
+    // to this memory location.
+    SDValue FIN = DAG.getFrameIndex(FI, MVT::i32);
+    MemOpChains.push_back(DAG.getStore(
+        Chain, dl, OutVals[i], FIN,
+        MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), FI), false,
+        false, 0));
+  }
+
+  // Transform all store nodes into one single node because
+  // all stores are independent of each other.
+  if (!MemOpChains.empty())
+    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, MemOpChains);
+
+  // Now handle return values copied to registers.
+  for (unsigned i = 0, e = RVLocs.size(); i != e; ++i) {
+    CCValAssign &VA = RVLocs[i];
+    if (!VA.isRegLoc())
+      continue;
+    // Copy the result values into the output registers.
+    Chain = DAG.getCopyToReg(Chain, dl, VA.getLocReg(), OutVals[i], Flag);
+
+    // guarantee that all emitted copies are
+    // stuck together, avoiding something bad
+    Flag = Chain.getValue(1);
+    RetOps.push_back(DAG.getRegister(VA.getLocReg(), VA.getLocVT()));
+  }
+
+  RetOps[0] = Chain;  // Update chain.
+
+  // Add the flag if we have it.
+  if (Flag.getNode())
+    RetOps.push_back(Flag);
+
+  return DAG.getNode(XCoreISD::RETSP, dl, MVT::Other, RetOps);
+}
+
+//===----------------------------------------------------------------------===//
+//  Other Lowering Code
+//===----------------------------------------------------------------------===//
+
+MachineBasicBlock *
+XCoreTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
+                                                 MachineBasicBlock *BB) const {
+  const TargetInstrInfo &TII = *Subtarget.getInstrInfo();
+  DebugLoc dl = MI->getDebugLoc();
+  assert((MI->getOpcode() == XCore::SELECT_CC) &&
+         "Unexpected instr type to insert");
+
+  // To "insert" a SELECT_CC instruction, we actually have to insert the diamond
+  // control-flow pattern.  The incoming instruction knows the destination vreg
+  // to set, the condition code register to branch on, the true/false values to
+  // select between, and a branch opcode to use.
+  const BasicBlock *LLVM_BB = BB->getBasicBlock();
+  MachineFunction::iterator It = ++BB->getIterator();
+
+  //  thisMBB:
+  //  ...
+  //   TrueVal = ...
+  //   cmpTY ccX, r1, r2
+  //   bCC copy1MBB
+  //   fallthrough --> copy0MBB
+  MachineBasicBlock *thisMBB = BB;
+  MachineFunction *F = BB->getParent();
+  MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
+  MachineBasicBlock *sinkMBB = F->CreateMachineBasicBlock(LLVM_BB);
+  F->insert(It, copy0MBB);
+  F->insert(It, sinkMBB);
+
+  // Transfer the remainder of BB and its successor edges to sinkMBB.
+  sinkMBB->splice(sinkMBB->begin(), BB,
+                  std::next(MachineBasicBlock::iterator(MI)), BB->end());
+  sinkMBB->transferSuccessorsAndUpdatePHIs(BB);
+
+  // Next, add the true and fallthrough blocks as its successors.
+  BB->addSuccessor(copy0MBB);
+  BB->addSuccessor(sinkMBB);
+
+  BuildMI(BB, dl, TII.get(XCore::BRFT_lru6))
+    .addReg(MI->getOperand(1).getReg()).addMBB(sinkMBB);
+
+  //  copy0MBB:
+  //   %FalseValue = ...
+  //   # fallthrough to sinkMBB
+  BB = copy0MBB;
+
+  // Update machine-CFG edges
+  BB->addSuccessor(sinkMBB);
+
+  //  sinkMBB:
+  //   %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ]
+  //  ...
+  BB = sinkMBB;
+  BuildMI(*BB, BB->begin(), dl,
+          TII.get(XCore::PHI), MI->getOperand(0).getReg())
+    .addReg(MI->getOperand(3).getReg()).addMBB(copy0MBB)
+    .addReg(MI->getOperand(2).getReg()).addMBB(thisMBB);
+
+  MI->eraseFromParent();   // The pseudo instruction is gone now.
+  return BB;
+}
+
+//===----------------------------------------------------------------------===//
+// Target Optimization Hooks
+//===----------------------------------------------------------------------===//
+
+SDValue XCoreTargetLowering::PerformDAGCombine(SDNode *N,
+                                             DAGCombinerInfo &DCI) const {
+  SelectionDAG &DAG = DCI.DAG;
+  SDLoc dl(N);
+  switch (N->getOpcode()) {
+  default: break;
+  case ISD::INTRINSIC_VOID:
+    switch (cast<ConstantSDNode>(N->getOperand(1))->getZExtValue()) {
+    case Intrinsic::xcore_outt:
+    case Intrinsic::xcore_outct:
+    case Intrinsic::xcore_chkct: {
+      SDValue OutVal = N->getOperand(3);
+      // These instructions ignore the high bits.
+      if (OutVal.hasOneUse()) {
+        unsigned BitWidth = OutVal.getValueSizeInBits();
+        APInt DemandedMask = APInt::getLowBitsSet(BitWidth, 8);
+        APInt KnownZero, KnownOne;
+        TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
+                                              !DCI.isBeforeLegalizeOps());
+        const TargetLowering &TLI = DAG.getTargetLoweringInfo();
+        if (TLO.ShrinkDemandedConstant(OutVal, DemandedMask) ||
+            TLI.SimplifyDemandedBits(OutVal, DemandedMask, KnownZero, KnownOne,
+                                     TLO))
+          DCI.CommitTargetLoweringOpt(TLO);
+      }
+      break;
+    }
+    case Intrinsic::xcore_setpt: {
+      SDValue Time = N->getOperand(3);
+      // This instruction ignores the high bits.
+      if (Time.hasOneUse()) {
+        unsigned BitWidth = Time.getValueSizeInBits();
+        APInt DemandedMask = APInt::getLowBitsSet(BitWidth, 16);
+        APInt KnownZero, KnownOne;
+        TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
+                                              !DCI.isBeforeLegalizeOps());
+        const TargetLowering &TLI = DAG.getTargetLoweringInfo();
+        if (TLO.ShrinkDemandedConstant(Time, DemandedMask) ||
+            TLI.SimplifyDemandedBits(Time, DemandedMask, KnownZero, KnownOne,
+                                     TLO))
+          DCI.CommitTargetLoweringOpt(TLO);
+      }
+      break;
+    }
+    }
+    break;
+  case XCoreISD::LADD: {
+    SDValue N0 = N->getOperand(0);
+    SDValue N1 = N->getOperand(1);
+    SDValue N2 = N->getOperand(2);
+    ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
+    ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
+    EVT VT = N0.getValueType();
+
+    // canonicalize constant to RHS
+    if (N0C && !N1C)
+      return DAG.getNode(XCoreISD::LADD, dl, DAG.getVTList(VT, VT), N1, N0, N2);
+
+    // fold (ladd 0, 0, x) -> 0, x & 1
+    if (N0C && N0C->isNullValue() && N1C && N1C->isNullValue()) {
+      SDValue Carry = DAG.getConstant(0, dl, VT);
+      SDValue Result = DAG.getNode(ISD::AND, dl, VT, N2,
+                                   DAG.getConstant(1, dl, VT));
+      SDValue Ops[] = { Result, Carry };
+      return DAG.getMergeValues(Ops, dl);
+    }
+
+    // fold (ladd x, 0, y) -> 0, add x, y iff carry is unused and y has only the
+    // low bit set
+    if (N1C && N1C->isNullValue() && N->hasNUsesOfValue(0, 1)) {
+      APInt KnownZero, KnownOne;
+      APInt Mask = APInt::getHighBitsSet(VT.getSizeInBits(),
+                                         VT.getSizeInBits() - 1);
+      DAG.computeKnownBits(N2, KnownZero, KnownOne);
+      if ((KnownZero & Mask) == Mask) {
+        SDValue Carry = DAG.getConstant(0, dl, VT);
+        SDValue Result = DAG.getNode(ISD::ADD, dl, VT, N0, N2);
+        SDValue Ops[] = { Result, Carry };
+        return DAG.getMergeValues(Ops, dl);
+      }
+    }
+  }
+  break;
+  case XCoreISD::LSUB: {
+    SDValue N0 = N->getOperand(0);
+    SDValue N1 = N->getOperand(1);
+    SDValue N2 = N->getOperand(2);
+    ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
+    ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
+    EVT VT = N0.getValueType();
+
+    // fold (lsub 0, 0, x) -> x, -x iff x has only the low bit set
+    if (N0C && N0C->isNullValue() && N1C && N1C->isNullValue()) {
+      APInt KnownZero, KnownOne;
+      APInt Mask = APInt::getHighBitsSet(VT.getSizeInBits(),
+                                         VT.getSizeInBits() - 1);
+      DAG.computeKnownBits(N2, KnownZero, KnownOne);
+      if ((KnownZero & Mask) == Mask) {
+        SDValue Borrow = N2;
+        SDValue Result = DAG.getNode(ISD::SUB, dl, VT,
+                                     DAG.getConstant(0, dl, VT), N2);
+        SDValue Ops[] = { Result, Borrow };
+        return DAG.getMergeValues(Ops, dl);
+      }
+    }
+
+    // fold (lsub x, 0, y) -> 0, sub x, y iff borrow is unused and y has only the
+    // low bit set
+    if (N1C && N1C->isNullValue() && N->hasNUsesOfValue(0, 1)) {
+      APInt KnownZero, KnownOne;
+      APInt Mask = APInt::getHighBitsSet(VT.getSizeInBits(),
+                                         VT.getSizeInBits() - 1);
+      DAG.computeKnownBits(N2, KnownZero, KnownOne);
+      if ((KnownZero & Mask) == Mask) {
+        SDValue Borrow = DAG.getConstant(0, dl, VT);
+        SDValue Result = DAG.getNode(ISD::SUB, dl, VT, N0, N2);
+        SDValue Ops[] = { Result, Borrow };
+        return DAG.getMergeValues(Ops, dl);
+      }
+    }
+  }
+  break;
+  case XCoreISD::LMUL: {
+    SDValue N0 = N->getOperand(0);
+    SDValue N1 = N->getOperand(1);
+    SDValue N2 = N->getOperand(2);
+    SDValue N3 = N->getOperand(3);
+    ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
+    ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
+    EVT VT = N0.getValueType();
+    // Canonicalize multiplicative constant to RHS. If both multiplicative
+    // operands are constant canonicalize smallest to RHS.
+    if ((N0C && !N1C) ||
+        (N0C && N1C && N0C->getZExtValue() < N1C->getZExtValue()))
+      return DAG.getNode(XCoreISD::LMUL, dl, DAG.getVTList(VT, VT),
+                         N1, N0, N2, N3);
+
+    // lmul(x, 0, a, b)
+    if (N1C && N1C->isNullValue()) {
+      // If the high result is unused fold to add(a, b)
+      if (N->hasNUsesOfValue(0, 0)) {
+        SDValue Lo = DAG.getNode(ISD::ADD, dl, VT, N2, N3);
+        SDValue Ops[] = { Lo, Lo };
+        return DAG.getMergeValues(Ops, dl);
+      }
+      // Otherwise fold to ladd(a, b, 0)
+      SDValue Result =
+        DAG.getNode(XCoreISD::LADD, dl, DAG.getVTList(VT, VT), N2, N3, N1);
+      SDValue Carry(Result.getNode(), 1);
+      SDValue Ops[] = { Carry, Result };
+      return DAG.getMergeValues(Ops, dl);
+    }
+  }
+  break;
+  case ISD::ADD: {
+    // Fold 32 bit expressions such as add(add(mul(x,y),a),b) ->
+    // lmul(x, y, a, b). The high result of lmul will be ignored.
+    // This is only profitable if the intermediate results are unused
+    // elsewhere.
+    SDValue Mul0, Mul1, Addend0, Addend1;
+    if (N->getValueType(0) == MVT::i32 &&
+        isADDADDMUL(SDValue(N, 0), Mul0, Mul1, Addend0, Addend1, true)) {
+      SDValue Ignored = DAG.getNode(XCoreISD::LMUL, dl,
+                                    DAG.getVTList(MVT::i32, MVT::i32), Mul0,
+                                    Mul1, Addend0, Addend1);
+      SDValue Result(Ignored.getNode(), 1);
+      return Result;
+    }
+    APInt HighMask = APInt::getHighBitsSet(64, 32);
+    // Fold 64 bit expression such as add(add(mul(x,y),a),b) ->
+    // lmul(x, y, a, b) if all operands are zero-extended. We do this
+    // before type legalization as it is messy to match the operands after
+    // that.
+    if (N->getValueType(0) == MVT::i64 &&
+        isADDADDMUL(SDValue(N, 0), Mul0, Mul1, Addend0, Addend1, false) &&
+        DAG.MaskedValueIsZero(Mul0, HighMask) &&
+        DAG.MaskedValueIsZero(Mul1, HighMask) &&
+        DAG.MaskedValueIsZero(Addend0, HighMask) &&
+        DAG.MaskedValueIsZero(Addend1, HighMask)) {
+      SDValue Mul0L = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
+                                  Mul0, DAG.getConstant(0, dl, MVT::i32));
+      SDValue Mul1L = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
+                                  Mul1, DAG.getConstant(0, dl, MVT::i32));
+      SDValue Addend0L = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
+                                     Addend0, DAG.getConstant(0, dl, MVT::i32));
+      SDValue Addend1L = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
+                                     Addend1, DAG.getConstant(0, dl, MVT::i32));
+      SDValue Hi = DAG.getNode(XCoreISD::LMUL, dl,
+                               DAG.getVTList(MVT::i32, MVT::i32), Mul0L, Mul1L,
+                               Addend0L, Addend1L);
+      SDValue Lo(Hi.getNode(), 1);
+      return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
+    }
+  }
+  break;
+  case ISD::STORE: {
+    // Replace unaligned store of unaligned load with memmove.
+    StoreSDNode *ST  = cast<StoreSDNode>(N);
+    if (!DCI.isBeforeLegalize() ||
+        allowsMisalignedMemoryAccesses(ST->getMemoryVT(),
+                                       ST->getAddressSpace(),
+                                       ST->getAlignment()) ||
+        ST->isVolatile() || ST->isIndexed()) {
+      break;
+    }
+    SDValue Chain = ST->getChain();
+
+    unsigned StoreBits = ST->getMemoryVT().getStoreSizeInBits();
+    assert((StoreBits % 8) == 0 &&
+           "Store size in bits must be a multiple of 8");
+    unsigned ABIAlignment = DAG.getDataLayout().getABITypeAlignment(
+        ST->getMemoryVT().getTypeForEVT(*DCI.DAG.getContext()));
+    unsigned Alignment = ST->getAlignment();
+    if (Alignment >= ABIAlignment) {
+      break;
+    }
+
+    if (LoadSDNode *LD = dyn_cast<LoadSDNode>(ST->getValue())) {
+      if (LD->hasNUsesOfValue(1, 0) && ST->getMemoryVT() == LD->getMemoryVT() &&
+        LD->getAlignment() == Alignment &&
+        !LD->isVolatile() && !LD->isIndexed() &&
+        Chain.reachesChainWithoutSideEffects(SDValue(LD, 1))) {
+        bool isTail = isInTailCallPosition(DAG, ST, Chain);
+        return DAG.getMemmove(Chain, dl, ST->getBasePtr(),
+                              LD->getBasePtr(),
+                              DAG.getConstant(StoreBits/8, dl, MVT::i32),
+                              Alignment, false, isTail, ST->getPointerInfo(),
+                              LD->getPointerInfo());
+      }
+    }
+    break;
+  }
+  }
+  return SDValue();
+}
+
+void XCoreTargetLowering::computeKnownBitsForTargetNode(const SDValue Op,
+                                                        APInt &KnownZero,
+                                                        APInt &KnownOne,
+                                                        const SelectionDAG &DAG,
+                                                        unsigned Depth) const {
+  KnownZero = KnownOne = APInt(KnownZero.getBitWidth(), 0);
+  switch (Op.getOpcode()) {
+  default: break;
+  case XCoreISD::LADD:
+  case XCoreISD::LSUB:
+    if (Op.getResNo() == 1) {
+      // Top bits of carry / borrow are clear.
+      KnownZero = APInt::getHighBitsSet(KnownZero.getBitWidth(),
+                                        KnownZero.getBitWidth() - 1);
+    }
+    break;
+  case ISD::INTRINSIC_W_CHAIN:
+    {
+      unsigned IntNo = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
+      switch (IntNo) {
+      case Intrinsic::xcore_getts:
+        // High bits are known to be zero.
+        KnownZero = APInt::getHighBitsSet(KnownZero.getBitWidth(),
+                                          KnownZero.getBitWidth() - 16);
+        break;
+      case Intrinsic::xcore_int:
+      case Intrinsic::xcore_inct:
+        // High bits are known to be zero.
+        KnownZero = APInt::getHighBitsSet(KnownZero.getBitWidth(),
+                                          KnownZero.getBitWidth() - 8);
+        break;
+      case Intrinsic::xcore_testct:
+        // Result is either 0 or 1.
+        KnownZero = APInt::getHighBitsSet(KnownZero.getBitWidth(),
+                                          KnownZero.getBitWidth() - 1);
+        break;
+      case Intrinsic::xcore_testwct:
+        // Result is in the range 0 - 4.
+        KnownZero = APInt::getHighBitsSet(KnownZero.getBitWidth(),
+                                          KnownZero.getBitWidth() - 3);
+        break;
+      }
+    }
+    break;
+  }
+}
+
+//===----------------------------------------------------------------------===//
+//  Addressing mode description hooks
+//===----------------------------------------------------------------------===//
+
+static inline bool isImmUs(int64_t val)
+{
+  return (val >= 0 && val <= 11);
+}
+
+static inline bool isImmUs2(int64_t val)
+{
+  return (val%2 == 0 && isImmUs(val/2));
+}
+
+static inline bool isImmUs4(int64_t val)
+{
+  return (val%4 == 0 && isImmUs(val/4));
+}
+
+/// isLegalAddressingMode - Return true if the addressing mode represented
+/// by AM is legal for this target, for a load/store of the specified type.
+bool XCoreTargetLowering::isLegalAddressingMode(const DataLayout &DL,
+                                                const AddrMode &AM, Type *Ty,
+                                                unsigned AS) const {
+  if (Ty->getTypeID() == Type::VoidTyID)
+    return AM.Scale == 0 && isImmUs(AM.BaseOffs) && isImmUs4(AM.BaseOffs);
+
+  unsigned Size = DL.getTypeAllocSize(Ty);
+  if (AM.BaseGV) {
+    return Size >= 4 && !AM.HasBaseReg && AM.Scale == 0 &&
+                 AM.BaseOffs%4 == 0;
+  }
+
+  switch (Size) {
+  case 1:
+    // reg + imm
+    if (AM.Scale == 0) {
+      return isImmUs(AM.BaseOffs);
+    }
+    // reg + reg
+    return AM.Scale == 1 && AM.BaseOffs == 0;
+  case 2:
+  case 3:
+    // reg + imm
+    if (AM.Scale == 0) {
+      return isImmUs2(AM.BaseOffs);
+    }
+    // reg + reg<<1
+    return AM.Scale == 2 && AM.BaseOffs == 0;
+  default:
+    // reg + imm
+    if (AM.Scale == 0) {
+      return isImmUs4(AM.BaseOffs);
+    }
+    // reg + reg<<2
+    return AM.Scale == 4 && AM.BaseOffs == 0;
+  }
+}
+
+//===----------------------------------------------------------------------===//
+//                           XCore Inline Assembly Support
+//===----------------------------------------------------------------------===//
+
+std::pair<unsigned, const TargetRegisterClass *>
+XCoreTargetLowering::getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
+                                                  StringRef Constraint,
+                                                  MVT VT) const {
+  if (Constraint.size() == 1) {
+    switch (Constraint[0]) {
+    default : break;
+    case 'r':
+      return std::make_pair(0U, &XCore::GRRegsRegClass);
+    }
+  }
+  // Use the default implementation in TargetLowering to convert the register
+  // constraint into a member of a register class.
+  return TargetLowering::getRegForInlineAsmConstraint(TRI, Constraint, VT);
+}