Beispiel #1
0
// Write ByVal Arg to arg registers and stack.
static void
WriteByValArg(SDValue& ByValChain, SDValue Chain, SDLoc DL,
              SmallVector<std::pair<unsigned, SDValue>, 16>& RegsToPass,
              SmallVector<SDValue, 8>& MemOpChains, int& LastFI,
              MachineFrameInfo *MFI, SelectionDAG &DAG, SDValue Arg,
              const CCValAssign &VA, const ISD::ArgFlagsTy& Flags,
              MVT PtrType, bool isLittle) {
  unsigned LocMemOffset = VA.getLocMemOffset();
  unsigned Offset = 0;
  uint32_t RemainingSize = Flags.getByValSize();
  unsigned ByValAlign = Flags.getByValAlign();

  if (RemainingSize == 0)
    return;

  // Create a fixed object on stack at offset LocMemOffset and copy
  // remaining part of byval arg to it using memcpy.
  SDValue Src = DAG.getNode(ISD::ADD, DL, MVT::i32, Arg,
                            DAG.getConstant(Offset, MVT::i32));
  LastFI = MFI->CreateFixedObject(RemainingSize, LocMemOffset, true);
  SDValue Dst = DAG.getFrameIndex(LastFI, PtrType);
  ByValChain = DAG.getMemcpy(ByValChain, DL, Dst, Src,
                             DAG.getConstant(RemainingSize, MVT::i32),
                             std::min(ByValAlign, (unsigned)4),
                             /*isVolatile=*/false, /*AlwaysInline=*/false,
                             MachinePointerInfo(0), MachinePointerInfo(0));
}
SDValue
X86SelectionDAGInfo::EmitTargetCodeForMemcpy(SelectionDAG &DAG, SDLoc dl,
                                        SDValue Chain, SDValue Dst, SDValue Src,
                                        SDValue Size, unsigned Align,
                                        bool isVolatile, bool AlwaysInline,
                                         MachinePointerInfo DstPtrInfo,
                                         MachinePointerInfo SrcPtrInfo) const {
  // This requires the copy size to be a constant, preferably
  // within a subtarget-specific limit.
  ConstantSDNode *ConstantSize = dyn_cast<ConstantSDNode>(Size);
  if (!ConstantSize)
    return SDValue();
  uint64_t SizeVal = ConstantSize->getZExtValue();
  if (!AlwaysInline && SizeVal > Subtarget->getMaxInlineSizeThreshold())
    return SDValue();

  /// If not DWORD aligned, it is more efficient to call the library.  However
  /// if calling the library is not allowed (AlwaysInline), then soldier on as
  /// the code generated here is better than the long load-store sequence we
  /// would otherwise get.
  if (!AlwaysInline && (Align & 3) != 0)
    return SDValue();

  // If to a segment-relative address space, use the default lowering.
  if (DstPtrInfo.getAddrSpace() >= 256 ||
      SrcPtrInfo.getAddrSpace() >= 256)
    return SDValue();

  // ESI might be used as a base pointer, in that case we can't simply overwrite
  // the register.  Fall back to generic code.
  const X86RegisterInfo *TRI =
      static_cast<const X86RegisterInfo *>(DAG.getTarget().getRegisterInfo());
  if (TRI->hasBasePointer(DAG.getMachineFunction()) &&
      TRI->getBaseRegister() == X86::ESI)
    return SDValue();

  MVT AVT;
  if (Align & 1)
    AVT = MVT::i8;
  else if (Align & 2)
    AVT = MVT::i16;
  else if (Align & 4)
    // DWORD aligned
    AVT = MVT::i32;
  else
    // QWORD aligned
    AVT = Subtarget->is64Bit() ? MVT::i64 : MVT::i32;

  unsigned UBytes = AVT.getSizeInBits() / 8;
  unsigned CountVal = SizeVal / UBytes;
  SDValue Count = DAG.getIntPtrConstant(CountVal);
  unsigned BytesLeft = SizeVal % UBytes;

  SDValue InFlag;
  Chain  = DAG.getCopyToReg(Chain, dl, Subtarget->is64Bit() ? X86::RCX :
                                                              X86::ECX,
                            Count, InFlag);
  InFlag = Chain.getValue(1);
  Chain  = DAG.getCopyToReg(Chain, dl, Subtarget->is64Bit() ? X86::RDI :
                                                              X86::EDI,
                            Dst, InFlag);
  InFlag = Chain.getValue(1);
  Chain  = DAG.getCopyToReg(Chain, dl, Subtarget->is64Bit() ? X86::RSI :
                                                              X86::ESI,
                            Src, InFlag);
  InFlag = Chain.getValue(1);

  SDVTList Tys = DAG.getVTList(MVT::Other, MVT::Glue);
  SDValue Ops[] = { Chain, DAG.getValueType(AVT), InFlag };
  SDValue RepMovs = DAG.getNode(X86ISD::REP_MOVS, dl, Tys, Ops);

  SmallVector<SDValue, 4> Results;
  Results.push_back(RepMovs);
  if (BytesLeft) {
    // Handle the last 1 - 7 bytes.
    unsigned Offset = SizeVal - BytesLeft;
    EVT DstVT = Dst.getValueType();
    EVT SrcVT = Src.getValueType();
    EVT SizeVT = Size.getValueType();
    Results.push_back(DAG.getMemcpy(Chain, dl,
                                    DAG.getNode(ISD::ADD, dl, DstVT, Dst,
                                                DAG.getConstant(Offset, DstVT)),
                                    DAG.getNode(ISD::ADD, dl, SrcVT, Src,
                                                DAG.getConstant(Offset, SrcVT)),
                                    DAG.getConstant(BytesLeft, SizeVT),
                                    Align, isVolatile, AlwaysInline,
                                    DstPtrInfo.getWithOffset(Offset),
                                    SrcPtrInfo.getWithOffset(Offset)));
  }

  return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Results);
}
Beispiel #3
0
/// LowerCCCCallTo - functions arguments are copied from virtual regs to
/// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted.
// TODO: sret.
SDValue MSP430TargetLowering::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, const 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());
  AnalyzeArguments(CCInfo, ArgLocs, Outs);

  // Get a count of how many bytes are to be pushed on the stack.
  unsigned NumBytes = CCInfo.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;
  SDValue StackPtr;

  // 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());

      if (!StackPtr.getNode())
        StackPtr = DAG.getCopyFromReg(Chain, dl, MSP430::SP, PtrVT);

      SDValue PtrOff =
          DAG.getNode(ISD::ADD, dl, PtrVT, StackPtr,
                      DAG.getIntPtrConstant(VA.getLocMemOffset(), dl));

      SDValue MemOp;
      ISD::ArgFlagsTy Flags = Outs[i].Flags;

      if (Flags.isByVal()) {
        SDValue SizeNode = DAG.getConstant(Flags.getByValSize(), dl, MVT::i16);
        MemOp = DAG.getMemcpy(Chain, dl, PtrOff, Arg, SizeNode,
                              Flags.getByValAlign(),
                              /*isVolatile*/false,
                              /*AlwaysInline=*/true,
                              /*isTailCall=*/false,
                              MachinePointerInfo(),
                              MachinePointerInfo());
      } else {
        MemOp = DAG.getStore(Chain, dl, Arg, PtrOff, MachinePointerInfo(),
                             false, false, 0);
      }

      MemOpChains.push_back(MemOp);
    }
  }

  // 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::i16);
  else if (ExternalSymbolSDNode *E = dyn_cast<ExternalSymbolSDNode>(Callee))
    Callee = DAG.getTargetExternalSymbol(E->getSymbol(), MVT::i16);

  // 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(MSP430ISD::CALL, 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, CallConv, isVarArg, Ins, dl,
                         DAG, InVals);
}
SDValue X86SelectionDAGInfo::EmitTargetCodeForMemcpy(
    SelectionDAG &DAG, const SDLoc &dl, SDValue Chain, SDValue Dst, SDValue Src,
    SDValue Size, unsigned Align, bool isVolatile, bool AlwaysInline,
    MachinePointerInfo DstPtrInfo, MachinePointerInfo SrcPtrInfo) const {
  // This requires the copy size to be a constant, preferably
  // within a subtarget-specific limit.
  ConstantSDNode *ConstantSize = dyn_cast<ConstantSDNode>(Size);
  const X86Subtarget &Subtarget =
      DAG.getMachineFunction().getSubtarget<X86Subtarget>();
  if (!ConstantSize)
    return SDValue();
  RepMovsRepeats Repeats(ConstantSize->getZExtValue());
  if (!AlwaysInline && Repeats.Size > Subtarget.getMaxInlineSizeThreshold())
    return SDValue();

  /// If not DWORD aligned, it is more efficient to call the library.  However
  /// if calling the library is not allowed (AlwaysInline), then soldier on as
  /// the code generated here is better than the long load-store sequence we
  /// would otherwise get.
  if (!AlwaysInline && (Align & 3) != 0)
    return SDValue();

  // If to a segment-relative address space, use the default lowering.
  if (DstPtrInfo.getAddrSpace() >= 256 ||
      SrcPtrInfo.getAddrSpace() >= 256)
    return SDValue();

  // If the base register might conflict with our physical registers, bail out.
  const MCPhysReg ClobberSet[] = {X86::RCX, X86::RSI, X86::RDI,
                                  X86::ECX, X86::ESI, X86::EDI};
  if (isBaseRegConflictPossible(DAG, ClobberSet))
    return SDValue();

  // If the target has enhanced REPMOVSB, then it's at least as fast to use
  // REP MOVSB instead of REP MOVS{W,D,Q}, and it avoids having to handle
  // BytesLeft.
  if (!Subtarget.hasERMSB() && !(Align & 1)) {
    if (Align & 2)
      // WORD aligned
      Repeats.AVT = MVT::i16;
    else if (Align & 4)
      // DWORD aligned
      Repeats.AVT = MVT::i32;
    else
      // QWORD aligned
      Repeats.AVT = Subtarget.is64Bit() ? MVT::i64 : MVT::i32;

    if (Repeats.BytesLeft() > 0 &&
        DAG.getMachineFunction().getFunction().optForMinSize()) {
      // When agressively optimizing for size, avoid generating the code to
      // handle BytesLeft.
      Repeats.AVT = MVT::i8;
    }
  }

  SDValue InFlag;
  Chain = DAG.getCopyToReg(Chain, dl, Subtarget.is64Bit() ? X86::RCX : X86::ECX,
                           DAG.getIntPtrConstant(Repeats.Count(), dl), InFlag);
  InFlag = Chain.getValue(1);
  Chain = DAG.getCopyToReg(Chain, dl, Subtarget.is64Bit() ? X86::RDI : X86::EDI,
                           Dst, InFlag);
  InFlag = Chain.getValue(1);
  Chain = DAG.getCopyToReg(Chain, dl, Subtarget.is64Bit() ? X86::RSI : X86::ESI,
                           Src, InFlag);
  InFlag = Chain.getValue(1);

  SDVTList Tys = DAG.getVTList(MVT::Other, MVT::Glue);
  SDValue Ops[] = { Chain, DAG.getValueType(Repeats.AVT), InFlag };
  SDValue RepMovs = DAG.getNode(X86ISD::REP_MOVS, dl, Tys, Ops);

  SmallVector<SDValue, 4> Results;
  Results.push_back(RepMovs);
  if (Repeats.BytesLeft()) {
    // Handle the last 1 - 7 bytes.
    unsigned Offset = Repeats.Size - Repeats.BytesLeft();
    EVT DstVT = Dst.getValueType();
    EVT SrcVT = Src.getValueType();
    EVT SizeVT = Size.getValueType();
    Results.push_back(DAG.getMemcpy(Chain, dl,
                                    DAG.getNode(ISD::ADD, dl, DstVT, Dst,
                                                DAG.getConstant(Offset, dl,
                                                                DstVT)),
                                    DAG.getNode(ISD::ADD, dl, SrcVT, Src,
                                                DAG.getConstant(Offset, dl,
                                                                SrcVT)),
                                    DAG.getConstant(Repeats.BytesLeft(), dl,
                                                    SizeVT),
                                    Align, isVolatile, AlwaysInline, false,
                                    DstPtrInfo.getWithOffset(Offset),
                                    SrcPtrInfo.getWithOffset(Offset)));
  }

  return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Results);
}
Beispiel #5
0
// LowerCCCCallTo - functions arguments are copied from virtual regs to
// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted.
SDValue LanaiTargetLowering::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());
  GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee);
  MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();

  NumFixedArgs = 0;
  if (IsVarArg && G) {
    const Function *CalleeFn = dyn_cast<Function>(G->getGlobal());
    if (CalleeFn)
      NumFixedArgs = CalleeFn->getFunctionType()->getNumParams();
  }
  if (NumFixedArgs)
    CCInfo.AnalyzeCallOperands(Outs, CC_Lanai32_VarArg);
  else {
    if (CallConv == CallingConv::Fast)
      CCInfo.AnalyzeCallOperands(Outs, CC_Lanai32_Fast);
    else
      CCInfo.AnalyzeCallOperands(Outs, CC_Lanai32);
  }

  // Get a count of how many bytes are to be pushed on the stack.
  unsigned NumBytes = CCInfo.getNextStackOffset();

  // Create local copies for byval args.
  SmallVector<SDValue, 8> ByValArgs;
  for (unsigned I = 0, E = Outs.size(); I != E; ++I) {
    ISD::ArgFlagsTy Flags = Outs[I].Flags;
    if (!Flags.isByVal())
      continue;

    SDValue Arg = OutVals[I];
    unsigned Size = Flags.getByValSize();
    unsigned Align = Flags.getByValAlign();

    int FI = MFI->CreateStackObject(Size, Align, false);
    SDValue FIPtr = DAG.getFrameIndex(FI, getPointerTy(DAG.getDataLayout()));
    SDValue SizeNode = DAG.getConstant(Size, DL, MVT::i32);

    Chain = DAG.getMemcpy(Chain, DL, FIPtr, Arg, SizeNode, Align,
                          /*IsVolatile=*/false,
                          /*AlwaysInline=*/false,
                          /*IsTailCall=*/false, MachinePointerInfo(),
                          MachinePointerInfo());
    ByValArgs.push_back(FIPtr);
  }

  Chain = DAG.getCALLSEQ_START(
      Chain,
      DAG.getConstant(NumBytes, DL, getPointerTy(DAG.getDataLayout()), true),
      DL);

  SmallVector<std::pair<unsigned, SDValue>, 4> RegsToPass;
  SmallVector<SDValue, 12> MemOpChains;
  SDValue StackPtr;

  // Walk the register/memloc assignments, inserting copies/loads.
  for (unsigned I = 0, J = 0, E = ArgLocs.size(); I != E; ++I) {
    CCValAssign &VA = ArgLocs[I];
    SDValue Arg = OutVals[I];
    ISD::ArgFlagsTy Flags = Outs[I].Flags;

    // Promote the value if needed.
    switch (VA.getLocInfo()) {
    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;
    default:
      llvm_unreachable("Unknown loc info!");
    }

    // Use local copy if it is a byval arg.
    if (Flags.isByVal())
      Arg = ByValArgs[J++];

    // 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());

      if (StackPtr.getNode() == 0)
        StackPtr = DAG.getCopyFromReg(Chain, DL, Lanai::SP,
                                      getPointerTy(DAG.getDataLayout()));

      SDValue PtrOff =
          DAG.getNode(ISD::ADD, DL, getPointerTy(DAG.getDataLayout()), StackPtr,
                      DAG.getIntPtrConstant(VA.getLocMemOffset(), DL));

      MemOpChains.push_back(DAG.getStore(
          Chain, DL, Arg, PtrOff, MachinePointerInfo(), false, false, 0));
    }
  }

  // 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,
                        ArrayRef<SDValue>(&MemOpChains[0], MemOpChains.size()));

  SDValue InFlag;

  // 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.
  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.
  uint8_t OpFlag = LanaiII::MO_NO_FLAG;
  if (G) {
    Callee = DAG.getTargetGlobalAddress(
        G->getGlobal(), DL, getPointerTy(DAG.getDataLayout()), 0, OpFlag);
  } else if (ExternalSymbolSDNode *E = dyn_cast<ExternalSymbolSDNode>(Callee)) {
    Callee = DAG.getTargetExternalSymbol(
        E->getSymbol(), getPointerTy(DAG.getDataLayout()), OpFlag);
  }

  // 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 a register mask operand representing the call-preserved registers.
  // TODO: Should return-twice functions be handled?
  const uint32_t *Mask =
      TRI->getCallPreservedMask(DAG.getMachineFunction(), CallConv);
  assert(Mask && "Missing call preserved mask for calling convention");
  Ops.push_back(DAG.getRegisterMask(Mask));

  // 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(LanaiISD::CALL, DL, NodeTys,
                      ArrayRef<SDValue>(&Ops[0], Ops.size()));
  InFlag = Chain.getValue(1);

  // Create the CALLSEQ_END node.
  Chain = DAG.getCALLSEQ_END(
      Chain,
      DAG.getConstant(NumBytes, DL, getPointerTy(DAG.getDataLayout()), true),
      DAG.getConstant(0, DL, getPointerTy(DAG.getDataLayout()), true), InFlag,
      DL);
  InFlag = Chain.getValue(1);

  // Handle result values, copying them out of physregs into vregs that we
  // return.
  return LowerCallResult(Chain, InFlag, CallConv, IsVarArg, Ins, DL, DAG,
                         InVals);
}
Beispiel #6
0
/// Transform physical registers into virtual registers, and generate load
/// operations for argument places on the stack.
SDValue ARCTargetLowering::LowerCallArguments(
    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();
  auto *AFI = MF.getInfo<ARCFunctionInfo>();

  // 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_ARC);

  unsigned StackSlotSize = 4;

  if (!IsVarArg)
    AFI->setReturnStackOffset(CCInfo.getNextStackOffset());

  // 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: {
        DEBUG(errs() << "LowerFormalArguments Unhandled argument type: "
                     << RegVT.getSimpleVT().SimpleTy << "\n");
        llvm_unreachable("Unhandled LowerFormalArguments type.");
      }
      case MVT::i32:
        unsigned VReg = RegInfo.createVirtualRegister(&ARC::GPR32RegClass);
        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().getStoreSize();
      assert((ObjSize <= StackSlotSize) && "Unhandled argument");

      // Create the frame index object for this incoming parameter...
      int FI = MFI.CreateFixedObject(ObjSize, 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));
    }
    const ArgDataPair ADP = {ArgIn, Ins[i].Flags};
    ArgData.push_back(ADP);
  }

  // 1b. CopyFromReg vararg registers.
  if (IsVarArg) {
    // Argument registers
    static const MCPhysReg ArgRegs[] = {ARC::R0, ARC::R1, ARC::R2, ARC::R3,
                                        ARC::R4, ARC::R5, ARC::R6, ARC::R7};
    auto *AFI = MF.getInfo<ARCFunctionInfo>();
    unsigned FirstVAReg = CCInfo.getFirstUnallocated(ArgRegs);
    if (FirstVAReg < array_lengthof(ArgRegs)) {
      int Offset = 0;
      // Save remaining registers, storing higher register numbers at a higher
      // address
      // There are (array_lengthof(ArgRegs) - FirstVAReg) registers which
      // need to be saved.
      int VarFI =
          MFI.CreateFixedObject((array_lengthof(ArgRegs) - FirstVAReg) * 4,
                                CCInfo.getNextStackOffset(), true);
      AFI->setVarArgsFrameIndex(VarFI);
      SDValue FIN = DAG.getFrameIndex(VarFI, MVT::i32);
      for (unsigned i = FirstVAReg; i < array_lengthof(ArgRegs); i++) {
        // Move argument from phys reg -> virt reg
        unsigned VReg = RegInfo.createVirtualRegister(&ARC::GPR32RegClass);
        RegInfo.addLiveIn(ArgRegs[i], VReg);
        SDValue Val = DAG.getCopyFromReg(Chain, dl, VReg, MVT::i32);
        CFRegNode.push_back(Val.getValue(Val->getNumValues() - 1));
        SDValue VAObj = DAG.getNode(ISD::ADD, dl, MVT::i32, FIN,
                                    DAG.getConstant(Offset, dl, MVT::i32));
        // Move argument from virt reg -> stack
        SDValue Store =
            DAG.getStore(Val.getValue(1), dl, Val, VAObj, MachinePointerInfo());
        MemOps.push_back(Store);
        Offset += 4;
      }
    } else {
      llvm_unreachable("Too many var args parameters.");
    }
  }

  // 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 (const auto &ArgDI : ArgData) {
    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;
}
SDValue
X86SelectionDAGInfo::EmitTargetCodeForMemcpy(SelectionDAG &DAG, DebugLoc dl,
                                        SDValue Chain, SDValue Dst, SDValue Src,
                                        SDValue Size, unsigned Align,
                                        bool isVolatile, bool AlwaysInline,
                                        const Value *DstSV,
                                        uint64_t DstSVOff,
                                        const Value *SrcSV,
                                        uint64_t SrcSVOff) const {
  // This requires the copy size to be a constant, preferrably
  // within a subtarget-specific limit.
  ConstantSDNode *ConstantSize = dyn_cast<ConstantSDNode>(Size);
  if (!ConstantSize)
    return SDValue();
  uint64_t SizeVal = ConstantSize->getZExtValue();
  if (!AlwaysInline && SizeVal > Subtarget->getMaxInlineSizeThreshold())
    return SDValue();

  /// If not DWORD aligned, call the library.
  if ((Align & 3) != 0)
    return SDValue();

  // DWORD aligned
  EVT AVT = MVT::i32;
  if (Subtarget->is64Bit() && ((Align & 0x7) == 0))  // QWORD aligned
    AVT = MVT::i64;

  unsigned UBytes = AVT.getSizeInBits() / 8;
  unsigned CountVal = SizeVal / UBytes;
  SDValue Count = DAG.getIntPtrConstant(CountVal);
  unsigned BytesLeft = SizeVal % UBytes;

  SDValue InFlag(0, 0);
  Chain  = DAG.getCopyToReg(Chain, dl, Subtarget->is64Bit() ? X86::RCX :
                                                              X86::ECX,
                            Count, InFlag);
  InFlag = Chain.getValue(1);
  Chain  = DAG.getCopyToReg(Chain, dl, Subtarget->is64Bit() ? X86::RDI :
                                                              X86::EDI,
                            Dst, InFlag);
  InFlag = Chain.getValue(1);
  Chain  = DAG.getCopyToReg(Chain, dl, Subtarget->is64Bit() ? X86::RSI :
                                                              X86::ESI,
                            Src, InFlag);
  InFlag = Chain.getValue(1);

  SDVTList Tys = DAG.getVTList(MVT::Other, MVT::Flag);
  SDValue Ops[] = { Chain, DAG.getValueType(AVT), InFlag };
  SDValue RepMovs = DAG.getNode(X86ISD::REP_MOVS, dl, Tys, Ops,
                                array_lengthof(Ops));

  SmallVector<SDValue, 4> Results;
  Results.push_back(RepMovs);
  if (BytesLeft) {
    // Handle the last 1 - 7 bytes.
    unsigned Offset = SizeVal - BytesLeft;
    EVT DstVT = Dst.getValueType();
    EVT SrcVT = Src.getValueType();
    EVT SizeVT = Size.getValueType();
    Results.push_back(DAG.getMemcpy(Chain, dl,
                                    DAG.getNode(ISD::ADD, dl, DstVT, Dst,
                                                DAG.getConstant(Offset, DstVT)),
                                    DAG.getNode(ISD::ADD, dl, SrcVT, Src,
                                                DAG.getConstant(Offset, SrcVT)),
                                    DAG.getConstant(BytesLeft, SizeVT),
                                    Align, isVolatile, AlwaysInline,
                                    DstSV, DstSVOff + Offset,
                                    SrcSV, SrcSVOff + Offset));
  }

  return DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
                     &Results[0], Results.size());
}
SDValue
X86SelectionDAGInfo::EmitTargetCodeForMemcpy(SelectionDAG &DAG, SDLoc dl,
        SDValue Chain, SDValue Dst, SDValue Src,
        SDValue Size, unsigned Align,
        bool isVolatile, bool AlwaysInline,
        MachinePointerInfo DstPtrInfo,
        MachinePointerInfo SrcPtrInfo) const {
    // This requires the copy size to be a constant, preferably
    // within a subtarget-specific limit.
    ConstantSDNode *ConstantSize = dyn_cast<ConstantSDNode>(Size);
    if (!ConstantSize)
        return SDValue();
    uint64_t SizeVal = ConstantSize->getZExtValue();
    if (!AlwaysInline && SizeVal > Subtarget->getMaxInlineSizeThreshold())
        return SDValue();

    /// If not DWORD aligned, it is more efficient to call the library.  However
    /// if calling the library is not allowed (AlwaysInline), then soldier on as
    /// the code generated here is better than the long load-store sequence we
    /// would otherwise get.
    if (!AlwaysInline && (Align & 3) != 0)
        return SDValue();

    // If to a segment-relative address space, use the default lowering.
    if (DstPtrInfo.getAddrSpace() >= 256 ||
            SrcPtrInfo.getAddrSpace() >= 256)
        return SDValue();

    // If ESI is used as a base pointer, we must preserve it when doing rep movs.
    const X86RegisterInfo *TRI =
        static_cast<const X86RegisterInfo *>(DAG.getTarget().getRegisterInfo());
    bool PreserveESI = TRI->hasBasePointer(DAG.getMachineFunction()) &&
                       TRI->getBaseRegister() == X86::ESI;

    MVT AVT;
    if (Align & 1)
        AVT = MVT::i8;
    else if (Align & 2)
        AVT = MVT::i16;
    else if (Align & 4)
        // DWORD aligned
        AVT = MVT::i32;
    else
        // QWORD aligned
        AVT = Subtarget->is64Bit() ? MVT::i64 : MVT::i32;

    unsigned UBytes = AVT.getSizeInBits() / 8;
    unsigned CountVal = SizeVal / UBytes;
    SDValue Count = DAG.getIntPtrConstant(CountVal);
    unsigned BytesLeft = SizeVal % UBytes;


    if (PreserveESI) {
        // Save ESI to a physical register. (We cannot use a virtual register
        // because if it is spilled we wouldn't be able to reload it.)
        // We don't glue this because the register dependencies are explicit.
        Chain = DAG.getCopyToReg(Chain, dl, X86::EDX,
                                 DAG.getRegister(X86::ESI, MVT::i32));
    }

    SDValue InGlue(0, 0);
    Chain  = DAG.getCopyToReg(Chain, dl, Subtarget->is64Bit() ? X86::RCX :
                              X86::ECX,
                              Count, InGlue);
    InGlue = Chain.getValue(1);
    Chain  = DAG.getCopyToReg(Chain, dl, Subtarget->is64Bit() ? X86::RDI :
                              X86::EDI,
                              Dst, InGlue);
    InGlue = Chain.getValue(1);
    Chain  = DAG.getCopyToReg(Chain, dl, Subtarget->is64Bit() ? X86::RSI :
                              X86::ESI,
                              Src, InGlue);
    InGlue = Chain.getValue(1);

    SDVTList Tys = DAG.getVTList(MVT::Other, MVT::Glue);
    SDValue Ops[] = { Chain, DAG.getValueType(AVT), InGlue };
    // FIXME: Make X86rep_movs explicitly use FCX, RDI, RSI instead of glue.
    SDValue RepMovs = DAG.getNode(X86ISD::REP_MOVS, dl, Tys, Ops,
                                  array_lengthof(Ops));

    if (PreserveESI) {
        InGlue = RepMovs.getValue(1);
        RepMovs = DAG.getCopyToReg(RepMovs, dl, X86::ESI,
                                   DAG.getRegister(X86::EDX, MVT::i32), InGlue);
    }

    SmallVector<SDValue, 4> Results;
    Results.push_back(RepMovs);


    if (BytesLeft) {
        // Handle the last 1 - 7 bytes.
        unsigned Offset = SizeVal - BytesLeft;
        EVT DstVT = Dst.getValueType();
        EVT SrcVT = Src.getValueType();
        EVT SizeVT = Size.getValueType();
        Results.push_back(DAG.getMemcpy(Chain, dl,
                                        DAG.getNode(ISD::ADD, dl, DstVT, Dst,
                                                DAG.getConstant(Offset, DstVT)),
                                        DAG.getNode(ISD::ADD, dl, SrcVT, Src,
                                                DAG.getConstant(Offset, SrcVT)),
                                        DAG.getConstant(BytesLeft, SizeVT),
                                        Align, isVolatile, AlwaysInline,
                                        DstPtrInfo.getWithOffset(Offset),
                                        SrcPtrInfo.getWithOffset(Offset)));
    }

    return DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
                       &Results[0], Results.size());
}
SDValue
SparcTargetLowering::LowerCall(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,
                               DebugLoc dl, SelectionDAG &DAG,
                               SmallVectorImpl<SDValue> &InVals) const {
  // Sparc target does not yet support tail call optimization.
  isTailCall = false;

  // Analyze operands of the call, assigning locations to each operand.
  SmallVector<CCValAssign, 16> ArgLocs;
  CCState CCInfo(CallConv, isVarArg, DAG.getTarget(), ArgLocs,
                 *DAG.getContext());
  CCInfo.AnalyzeCallOperands(Outs, CC_Sparc32);

  // Get the size of the outgoing arguments stack space requirement.
  unsigned ArgsSize = CCInfo.getNextStackOffset();

  // Keep stack frames 8-byte aligned.
  ArgsSize = (ArgsSize+7) & ~7;

  MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();

  //Create local copies for byval args.
  SmallVector<SDValue, 8> ByValArgs;
  for (unsigned i = 0,  e = Outs.size(); i != e; ++i) {
    ISD::ArgFlagsTy Flags = Outs[i].Flags;
    if (!Flags.isByVal())
      continue;

    SDValue Arg = OutVals[i];
    unsigned Size = Flags.getByValSize();
    unsigned Align = Flags.getByValAlign();

    int FI = MFI->CreateStackObject(Size, Align, false);
    SDValue FIPtr = DAG.getFrameIndex(FI, getPointerTy());
    SDValue SizeNode = DAG.getConstant(Size, MVT::i32);

    Chain = DAG.getMemcpy(Chain, dl, FIPtr, Arg, SizeNode, Align,
                          false,        //isVolatile,
                          (Size <= 32), //AlwaysInline if size <= 32
                          MachinePointerInfo(), MachinePointerInfo());
    ByValArgs.push_back(FIPtr);
  }

  Chain = DAG.getCALLSEQ_START(Chain, DAG.getIntPtrConstant(ArgsSize, true));

  SmallVector<std::pair<unsigned, SDValue>, 8> RegsToPass;
  SmallVector<SDValue, 8> MemOpChains;

  const unsigned StackOffset = 92;
  bool hasStructRetAttr = false;
  // Walk the register/memloc assignments, inserting copies/loads.
  for (unsigned i = 0, realArgIdx = 0, byvalArgIdx = 0, e = ArgLocs.size();
       i != e;
       ++i, ++realArgIdx) {
    CCValAssign &VA = ArgLocs[i];
    SDValue Arg = OutVals[realArgIdx];

    ISD::ArgFlagsTy Flags = Outs[realArgIdx].Flags;

    //Use local copy if it is a byval arg.
    if (Flags.isByVal())
      Arg = ByValArgs[byvalArgIdx++];

    // 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;
    case CCValAssign::BCvt:
      Arg = DAG.getNode(ISD::BITCAST, dl, VA.getLocVT(), Arg);
      break;
    }

    if (Flags.isSRet()) {
      assert(VA.needsCustom());
      // store SRet argument in %sp+64
      SDValue StackPtr = DAG.getRegister(SP::O6, MVT::i32);
      SDValue PtrOff = DAG.getIntPtrConstant(64);
      PtrOff = DAG.getNode(ISD::ADD, dl, MVT::i32, StackPtr, PtrOff);
      MemOpChains.push_back(DAG.getStore(Chain, dl, Arg, PtrOff,
                                         MachinePointerInfo(),
                                         false, false, 0));
      hasStructRetAttr = true;
      continue;
    }

    if (VA.needsCustom()) {
      assert(VA.getLocVT() == MVT::f64);

      if (VA.isMemLoc()) {
        unsigned Offset = VA.getLocMemOffset() + StackOffset;
        //if it is double-word aligned, just store.
        if (Offset % 8 == 0) {
          SDValue StackPtr = DAG.getRegister(SP::O6, MVT::i32);
          SDValue PtrOff = DAG.getIntPtrConstant(Offset);
          PtrOff = DAG.getNode(ISD::ADD, dl, MVT::i32, StackPtr, PtrOff);
          MemOpChains.push_back(DAG.getStore(Chain, dl, Arg, PtrOff,
                                             MachinePointerInfo(),
                                             false, false, 0));
          continue;
        }
      }

      SDValue StackPtr = DAG.CreateStackTemporary(MVT::f64, MVT::i32);
      SDValue Store = DAG.getStore(DAG.getEntryNode(), dl,
                                   Arg, StackPtr, MachinePointerInfo(),
                                   false, false, 0);
      // Sparc is big-endian, so the high part comes first.
      SDValue Hi = DAG.getLoad(MVT::i32, dl, Store, StackPtr,
                               MachinePointerInfo(), false, false, 0);
      // Increment the pointer to the other half.
      StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
                             DAG.getIntPtrConstant(4));
      // Load the low part.
      SDValue Lo = DAG.getLoad(MVT::i32, dl, Store, StackPtr,
                               MachinePointerInfo(), false, false, 0);

      if (VA.isRegLoc()) {
        RegsToPass.push_back(std::make_pair(VA.getLocReg(), Hi));
        assert(i+1 != e);
        CCValAssign &NextVA = ArgLocs[++i];
        if (NextVA.isRegLoc()) {
          RegsToPass.push_back(std::make_pair(NextVA.getLocReg(), Lo));
        } else {
          //Store the low part in stack.
          unsigned Offset = NextVA.getLocMemOffset() + StackOffset;
          SDValue StackPtr = DAG.getRegister(SP::O6, MVT::i32);
          SDValue PtrOff = DAG.getIntPtrConstant(Offset);
          PtrOff = DAG.getNode(ISD::ADD, dl, MVT::i32, StackPtr, PtrOff);
          MemOpChains.push_back(DAG.getStore(Chain, dl, Lo, PtrOff,
                                             MachinePointerInfo(),
                                             false, false, 0));
        }
      } else {
        unsigned Offset = VA.getLocMemOffset() + StackOffset;
        // Store the high part.
        SDValue StackPtr = DAG.getRegister(SP::O6, MVT::i32);
        SDValue PtrOff = DAG.getIntPtrConstant(Offset);
        PtrOff = DAG.getNode(ISD::ADD, dl, MVT::i32, StackPtr, PtrOff);
        MemOpChains.push_back(DAG.getStore(Chain, dl, Hi, PtrOff,
                                           MachinePointerInfo(),
                                           false, false, 0));
        // Store the low part.
        PtrOff = DAG.getIntPtrConstant(Offset+4);
        PtrOff = DAG.getNode(ISD::ADD, dl, MVT::i32, StackPtr, PtrOff);
        MemOpChains.push_back(DAG.getStore(Chain, dl, Lo, PtrOff,
                                           MachinePointerInfo(),
                                           false, false, 0));
      }
      continue;
    }

    // Arguments that can be passed on register must be kept at
    // RegsToPass vector
    if (VA.isRegLoc()) {
      if (VA.getLocVT() != MVT::f32) {
        RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
        continue;
      }
      Arg = DAG.getNode(ISD::BITCAST, dl, MVT::i32, Arg);
      RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
      continue;
    }

    assert(VA.isMemLoc());

    // Create a store off the stack pointer for this argument.
    SDValue StackPtr = DAG.getRegister(SP::O6, MVT::i32);
    SDValue PtrOff = DAG.getIntPtrConstant(VA.getLocMemOffset()+StackOffset);
    PtrOff = DAG.getNode(ISD::ADD, dl, MVT::i32, StackPtr, PtrOff);
    MemOpChains.push_back(DAG.getStore(Chain, dl, Arg, PtrOff,
                                       MachinePointerInfo(),
                                       false, false, 0));
  }


  // Emit all stores, make sure the occur before any copies into physregs.
  if (!MemOpChains.empty())
    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
                        &MemOpChains[0], MemOpChains.size());

  // 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) {
    unsigned Reg = RegsToPass[i].first;
    // Remap I0->I7 -> O0->O7.
    if (Reg >= SP::I0 && Reg <= SP::I7)
      Reg = Reg-SP::I0+SP::O0;

    Chain = DAG.getCopyToReg(Chain, dl, Reg, RegsToPass[i].second, InFlag);
    InFlag = Chain.getValue(1);
  }

  unsigned SRetArgSize = (hasStructRetAttr)? getSRetArgSize(DAG, Callee):0;

  // 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);

  // 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);
  if (hasStructRetAttr)
    Ops.push_back(DAG.getTargetConstant(SRetArgSize, MVT::i32));
  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
    unsigned Reg = RegsToPass[i].first;
    if (Reg >= SP::I0 && Reg <= SP::I7)
      Reg = Reg-SP::I0+SP::O0;

    Ops.push_back(DAG.getRegister(Reg, RegsToPass[i].second.getValueType()));
  }
  if (InFlag.getNode())
    Ops.push_back(InFlag);

  Chain = DAG.getNode(SPISD::CALL, dl, NodeTys, &Ops[0], Ops.size());
  InFlag = Chain.getValue(1);

  Chain = DAG.getCALLSEQ_END(Chain, DAG.getIntPtrConstant(ArgsSize, true),
                             DAG.getIntPtrConstant(0, true), InFlag);
  InFlag = Chain.getValue(1);

  // Assign locations to each value returned by this call.
  SmallVector<CCValAssign, 16> RVLocs;
  CCState RVInfo(CallConv, isVarArg, DAG.getTarget(),
                 RVLocs, *DAG.getContext());

  RVInfo.AnalyzeCallResult(Ins, RetCC_Sparc32);

  // Copy all of the result registers out of their specified physreg.
  for (unsigned i = 0; i != RVLocs.size(); ++i) {
    unsigned Reg = RVLocs[i].getLocReg();

    // Remap I0->I7 -> O0->O7.
    if (Reg >= SP::I0 && Reg <= SP::I7)
      Reg = Reg-SP::I0+SP::O0;

    Chain = DAG.getCopyFromReg(Chain, dl, Reg,
                               RVLocs[i].getValVT(), InFlag).getValue(1);
    InFlag = Chain.getValue(2);
    InVals.push_back(Chain.getValue(0));
  }

  return Chain;
}