+SDValue MSP430TargetLowering::LowerGlobalAddress(SDValue Op,
+ SelectionDAG &DAG) const {
+ const GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
+ int64_t Offset = cast<GlobalAddressSDNode>(Op)->getOffset();
+
+ // Create the TargetGlobalAddress node, folding in the constant offset.
+ SDValue Result = DAG.getTargetGlobalAddress(GV, getPointerTy(), Offset);
+ return DAG.getNode(MSP430ISD::Wrapper, Op.getDebugLoc(),
+ getPointerTy(), Result);
+}
+
+SDValue MSP430TargetLowering::LowerExternalSymbol(SDValue Op,
+ SelectionDAG &DAG) const {
+ DebugLoc dl = Op.getDebugLoc();
+ const char *Sym = cast<ExternalSymbolSDNode>(Op)->getSymbol();
+ SDValue Result = DAG.getTargetExternalSymbol(Sym, getPointerTy());
+
+ return DAG.getNode(MSP430ISD::Wrapper, dl, getPointerTy(), Result);;
+}
+
+SDValue MSP430TargetLowering::LowerBlockAddress(SDValue Op,
+ SelectionDAG &DAG) const {
+ DebugLoc dl = Op.getDebugLoc();
+ const BlockAddress *BA = cast<BlockAddressSDNode>(Op)->getBlockAddress();
+ SDValue Result = DAG.getBlockAddress(BA, getPointerTy(), /*isTarget=*/true);
+
+ return DAG.getNode(MSP430ISD::Wrapper, dl, getPointerTy(), Result);;
+}
+
+static SDValue EmitCMP(SDValue &LHS, SDValue &RHS, SDValue &TargetCC,
+ ISD::CondCode CC,
+ DebugLoc dl, SelectionDAG &DAG) {
+ // FIXME: Handle bittests someday
+ assert(!LHS.getValueType().isFloatingPoint() && "We don't handle FP yet");
+
+ // FIXME: Handle jump negative someday
+ MSP430CC::CondCodes TCC = MSP430CC::COND_INVALID;
+ switch (CC) {
+ default: llvm_unreachable("Invalid integer condition!");
+ case ISD::SETEQ:
+ TCC = MSP430CC::COND_E; // aka COND_Z
+ // Minor optimization: if LHS is a constant, swap operands, then the
+ // constant can be folded into comparison.
+ if (LHS.getOpcode() == ISD::Constant)
+ std::swap(LHS, RHS);
+ break;
+ case ISD::SETNE:
+ TCC = MSP430CC::COND_NE; // aka COND_NZ
+ // Minor optimization: if LHS is a constant, swap operands, then the
+ // constant can be folded into comparison.
+ if (LHS.getOpcode() == ISD::Constant)
+ std::swap(LHS, RHS);
+ break;
+ case ISD::SETULE:
+ std::swap(LHS, RHS); // FALLTHROUGH
+ case ISD::SETUGE:
+ // Turn lhs u>= rhs with lhs constant into rhs u< lhs+1, this allows us to
+ // fold constant into instruction.
+ if (const ConstantSDNode * C = dyn_cast<ConstantSDNode>(LHS)) {
+ LHS = RHS;
+ RHS = DAG.getConstant(C->getSExtValue() + 1, C->getValueType(0));
+ TCC = MSP430CC::COND_LO;
+ break;
+ }
+ TCC = MSP430CC::COND_HS; // aka COND_C
+ break;
+ case ISD::SETUGT:
+ std::swap(LHS, RHS); // FALLTHROUGH
+ case ISD::SETULT:
+ // Turn lhs u< rhs with lhs constant into rhs u>= lhs+1, this allows us to
+ // fold constant into instruction.
+ if (const ConstantSDNode * C = dyn_cast<ConstantSDNode>(LHS)) {
+ LHS = RHS;
+ RHS = DAG.getConstant(C->getSExtValue() + 1, C->getValueType(0));
+ TCC = MSP430CC::COND_HS;
+ break;
+ }
+ TCC = MSP430CC::COND_LO; // aka COND_NC
+ break;
+ case ISD::SETLE:
+ std::swap(LHS, RHS); // FALLTHROUGH
+ case ISD::SETGE:
+ // Turn lhs >= rhs with lhs constant into rhs < lhs+1, this allows us to
+ // fold constant into instruction.
+ if (const ConstantSDNode * C = dyn_cast<ConstantSDNode>(LHS)) {
+ LHS = RHS;
+ RHS = DAG.getConstant(C->getSExtValue() + 1, C->getValueType(0));
+ TCC = MSP430CC::COND_L;
+ break;
+ }
+ TCC = MSP430CC::COND_GE;
+ break;
+ case ISD::SETGT:
+ std::swap(LHS, RHS); // FALLTHROUGH
+ case ISD::SETLT:
+ // Turn lhs < rhs with lhs constant into rhs >= lhs+1, this allows us to
+ // fold constant into instruction.
+ if (const ConstantSDNode * C = dyn_cast<ConstantSDNode>(LHS)) {
+ LHS = RHS;
+ RHS = DAG.getConstant(C->getSExtValue() + 1, C->getValueType(0));
+ TCC = MSP430CC::COND_GE;
+ break;
+ }
+ TCC = MSP430CC::COND_L;
+ break;
+ }
+
+ TargetCC = DAG.getConstant(TCC, MVT::i8);
+ return DAG.getNode(MSP430ISD::CMP, dl, MVT::Flag, LHS, RHS);
+}
+
+
+SDValue MSP430TargetLowering::LowerBR_CC(SDValue Op, SelectionDAG &DAG) const {
+ SDValue Chain = Op.getOperand(0);
+ ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(1))->get();
+ SDValue LHS = Op.getOperand(2);
+ SDValue RHS = Op.getOperand(3);
+ SDValue Dest = Op.getOperand(4);
+ DebugLoc dl = Op.getDebugLoc();
+
+ SDValue TargetCC;
+ SDValue Flag = EmitCMP(LHS, RHS, TargetCC, CC, dl, DAG);
+
+ return DAG.getNode(MSP430ISD::BR_CC, dl, Op.getValueType(),
+ Chain, Dest, TargetCC, Flag);
+}
+
+SDValue MSP430TargetLowering::LowerSETCC(SDValue Op, SelectionDAG &DAG) const {
+ SDValue LHS = Op.getOperand(0);
+ SDValue RHS = Op.getOperand(1);
+ DebugLoc dl = Op.getDebugLoc();
+
+ // If we are doing an AND and testing against zero, then the CMP
+ // will not be generated. The AND (or BIT) will generate the condition codes,
+ // but they are different from CMP.
+ // FIXME: since we're doing a post-processing, use a pseudoinstr here, so
+ // lowering & isel wouldn't diverge.
+ bool andCC = false;
+ if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(RHS)) {
+ if (RHSC->isNullValue() && LHS.hasOneUse() &&
+ (LHS.getOpcode() == ISD::AND ||
+ (LHS.getOpcode() == ISD::TRUNCATE &&
+ LHS.getOperand(0).getOpcode() == ISD::AND))) {
+ andCC = true;
+ }
+ }
+ ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(2))->get();
+ SDValue TargetCC;
+ SDValue Flag = EmitCMP(LHS, RHS, TargetCC, CC, dl, DAG);
+
+ // Get the condition codes directly from the status register, if its easy.
+ // Otherwise a branch will be generated. Note that the AND and BIT
+ // instructions generate different flags than CMP, the carry bit can be used
+ // for NE/EQ.
+ bool Invert = false;
+ bool Shift = false;
+ bool Convert = true;
+ switch (cast<ConstantSDNode>(TargetCC)->getZExtValue()) {
+ default:
+ Convert = false;
+ break;
+ case MSP430CC::COND_HS:
+ // Res = SRW & 1, no processing is required
+ break;
+ case MSP430CC::COND_LO:
+ // Res = ~(SRW & 1)
+ Invert = true;
+ break;
+ case MSP430CC::COND_NE:
+ if (andCC) {
+ // C = ~Z, thus Res = SRW & 1, no processing is required
+ } else {
+ // Res = ~((SRW >> 1) & 1)
+ Shift = true;
+ Invert = true;
+ }
+ break;
+ case MSP430CC::COND_E:
+ Shift = true;
+ // C = ~Z for AND instruction, thus we can put Res = ~(SRW & 1), however,
+ // Res = (SRW >> 1) & 1 is 1 word shorter.
+ break;
+ }
+ EVT VT = Op.getValueType();
+ SDValue One = DAG.getConstant(1, VT);
+ if (Convert) {
+ SDValue SR = DAG.getCopyFromReg(DAG.getEntryNode(), dl, MSP430::SRW,
+ MVT::i16, Flag);
+ if (Shift)
+ // FIXME: somewhere this is turned into a SRL, lower it MSP specific?
+ SR = DAG.getNode(ISD::SRA, dl, MVT::i16, SR, One);
+ SR = DAG.getNode(ISD::AND, dl, MVT::i16, SR, One);
+ if (Invert)
+ SR = DAG.getNode(ISD::XOR, dl, MVT::i16, SR, One);
+ return SR;
+ } else {
+ SDValue Zero = DAG.getConstant(0, VT);
+ SDVTList VTs = DAG.getVTList(Op.getValueType(), MVT::Flag);
+ SmallVector<SDValue, 4> Ops;
+ Ops.push_back(One);
+ Ops.push_back(Zero);
+ Ops.push_back(TargetCC);
+ Ops.push_back(Flag);
+ return DAG.getNode(MSP430ISD::SELECT_CC, dl, VTs, &Ops[0], Ops.size());
+ }
+}
+
+SDValue MSP430TargetLowering::LowerSELECT_CC(SDValue Op,
+ SelectionDAG &DAG) const {
+ SDValue LHS = Op.getOperand(0);
+ SDValue RHS = Op.getOperand(1);
+ SDValue TrueV = Op.getOperand(2);
+ SDValue FalseV = Op.getOperand(3);
+ ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(4))->get();
+ DebugLoc dl = Op.getDebugLoc();
+
+ SDValue TargetCC;
+ SDValue Flag = EmitCMP(LHS, RHS, TargetCC, CC, dl, DAG);
+
+ SDVTList VTs = DAG.getVTList(Op.getValueType(), MVT::Flag);
+ SmallVector<SDValue, 4> Ops;
+ Ops.push_back(TrueV);
+ Ops.push_back(FalseV);
+ Ops.push_back(TargetCC);
+ Ops.push_back(Flag);
+
+ return DAG.getNode(MSP430ISD::SELECT_CC, dl, VTs, &Ops[0], Ops.size());
+}
+
+SDValue MSP430TargetLowering::LowerSIGN_EXTEND(SDValue Op,
+ SelectionDAG &DAG) const {
+ SDValue Val = Op.getOperand(0);
+ EVT VT = Op.getValueType();
+ DebugLoc dl = Op.getDebugLoc();
+
+ assert(VT == MVT::i16 && "Only support i16 for now!");
+
+ return DAG.getNode(ISD::SIGN_EXTEND_INREG, dl, VT,
+ DAG.getNode(ISD::ANY_EXTEND, dl, VT, Val),
+ DAG.getValueType(Val.getValueType()));
+}
+
+SDValue
+MSP430TargetLowering::getReturnAddressFrameIndex(SelectionDAG &DAG) const {
+ MachineFunction &MF = DAG.getMachineFunction();
+ MSP430MachineFunctionInfo *FuncInfo = MF.getInfo<MSP430MachineFunctionInfo>();
+ int ReturnAddrIndex = FuncInfo->getRAIndex();
+
+ if (ReturnAddrIndex == 0) {
+ // Set up a frame object for the return address.
+ uint64_t SlotSize = TD->getPointerSize();
+ ReturnAddrIndex = MF.getFrameInfo()->CreateFixedObject(SlotSize, -SlotSize,
+ true);
+ FuncInfo->setRAIndex(ReturnAddrIndex);
+ }
+
+ return DAG.getFrameIndex(ReturnAddrIndex, getPointerTy());
+}
+
+SDValue MSP430TargetLowering::LowerRETURNADDR(SDValue Op,
+ SelectionDAG &DAG) const {
+ MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
+ MFI->setReturnAddressIsTaken(true);
+
+ unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
+ DebugLoc dl = Op.getDebugLoc();
+
+ if (Depth > 0) {
+ SDValue FrameAddr = LowerFRAMEADDR(Op, DAG);
+ SDValue Offset =
+ DAG.getConstant(TD->getPointerSize(), MVT::i16);
+ return DAG.getLoad(getPointerTy(), dl, DAG.getEntryNode(),
+ DAG.getNode(ISD::ADD, dl, getPointerTy(),
+ FrameAddr, Offset),
+ NULL, 0, false, false, 0);
+ }
+
+ // Just load the return address.
+ SDValue RetAddrFI = getReturnAddressFrameIndex(DAG);
+ return DAG.getLoad(getPointerTy(), dl, DAG.getEntryNode(),
+ RetAddrFI, NULL, 0, false, false, 0);
+}
+
+SDValue MSP430TargetLowering::LowerFRAMEADDR(SDValue Op,
+ SelectionDAG &DAG) const {
+ MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
+ MFI->setFrameAddressIsTaken(true);
+
+ EVT VT = Op.getValueType();
+ DebugLoc dl = Op.getDebugLoc(); // FIXME probably not meaningful
+ unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
+ SDValue FrameAddr = DAG.getCopyFromReg(DAG.getEntryNode(), dl,
+ MSP430::FPW, VT);
+ while (Depth--)
+ FrameAddr = DAG.getLoad(VT, dl, DAG.getEntryNode(), FrameAddr, NULL, 0,
+ false, false, 0);
+ return FrameAddr;
+}
+
+/// getPostIndexedAddressParts - returns true by value, base pointer and
+/// offset pointer and addressing mode by reference if this node can be
+/// combined with a load / store to form a post-indexed load / store.
+bool MSP430TargetLowering::getPostIndexedAddressParts(SDNode *N, SDNode *Op,
+ SDValue &Base,
+ SDValue &Offset,
+ ISD::MemIndexedMode &AM,
+ SelectionDAG &DAG) const {
+
+ LoadSDNode *LD = cast<LoadSDNode>(N);
+ if (LD->getExtensionType() != ISD::NON_EXTLOAD)
+ return false;
+
+ EVT VT = LD->getMemoryVT();
+ if (VT != MVT::i8 && VT != MVT::i16)
+ return false;
+
+ if (Op->getOpcode() != ISD::ADD)
+ return false;
+
+ if (ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(Op->getOperand(1))) {
+ uint64_t RHSC = RHS->getZExtValue();
+ if ((VT == MVT::i16 && RHSC != 2) ||
+ (VT == MVT::i8 && RHSC != 1))
+ return false;
+
+ Base = Op->getOperand(0);
+ Offset = DAG.getConstant(RHSC, VT);
+ AM = ISD::POST_INC;
+ return true;
+ }
+
+ return false;
+}
+
+