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      SDValue NewOp = RewriteAsNarrowerShuffle(V1, V2, VT, PermMask,
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        SDValue NewV1 = NewOp.getOperand(0);
        SDValue NewV2 = NewOp.getOperand(1);
        SDValue NewMask = NewOp.getOperand(2);
        if (isCommutedMOVL(NewMask.getNode(), true, false)) {
          NewOp = CommuteVectorShuffle(NewOp, NewV1, NewV2, NewMask, DAG);
          return getVZextMovL(VT, NewOp.getValueType(), NewV2, DAG, Subtarget);
    } else if (ISD::isBuildVectorAllZeros(V1.getNode())) {
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      SDValue NewOp= RewriteAsNarrowerShuffle(V1, V2, VT, PermMask,
      if (NewOp.getNode() && X86::isMOVLMask(NewOp.getOperand(2).getNode()))
        return getVZextMovL(VT, NewOp.getValueType(), NewOp.getOperand(1),
  // Check if this can be converted into a logical shift.
  bool isLeft = false;
  unsigned ShAmt = 0;
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  SDValue ShVal;
  bool isShift = isVectorShift(Op, PermMask, DAG, isLeft, ShVal, ShAmt);
  if (isShift && ShVal.hasOneUse()) {
    // If the shifted value has multiple uses, it may be cheaper to use 
    // v_set0 + movlhps or movhlps, etc.
    MVT EVT = VT.getVectorElementType();
    ShAmt *= EVT.getSizeInBits();
    return getVShift(isLeft, VT, ShVal, ShAmt, DAG, *this);
  }

      return getVZextMovL(VT, VT, V2, DAG, Subtarget);
  if (!isMMX && (X86::isMOVSHDUPMask(PermMask.getNode()) ||
                 X86::isMOVSLDUPMask(PermMask.getNode()) ||
                 X86::isMOVHLPSMask(PermMask.getNode()) ||
                 X86::isMOVHPMask(PermMask.getNode()) ||
                 X86::isMOVLPMask(PermMask.getNode())))
    return Op;
  if (ShouldXformToMOVHLPS(PermMask.getNode()) ||
      ShouldXformToMOVLP(V1.getNode(), V2.getNode(), PermMask.getNode()))
    return CommuteVectorShuffle(Op, V1, V2, PermMask, DAG);
  if (isShift) {
    // No better options. Use a vshl / vsrl.
    MVT EVT = VT.getVectorElementType();
    ShAmt *= EVT.getSizeInBits();
    return getVShift(isLeft, VT, ShVal, ShAmt, DAG, *this);
  }

  // FIXME: This should also accept a bitcast of a splat?  Be careful, not
  // 1,1,1,1 -> v8i16 though.
  V1IsSplat = isSplatVector(V1.getNode());
  V2IsSplat = isSplatVector(V2.getNode());
  
  // Canonicalize the splat or undef, if present, to be on the RHS.
  if ((V1IsSplat || V1IsUndef) && !(V2IsSplat || V2IsUndef)) {
    Op = CommuteVectorShuffle(Op, V1, V2, PermMask, DAG);
    std::swap(V1IsSplat, V2IsSplat);
    std::swap(V1IsUndef, V2IsUndef);
  // FIXME: Figure out a cleaner way to do this.
  if (isCommutedMOVL(PermMask.getNode(), V2IsSplat, V2IsUndef)) {
    if (V2IsUndef) return V1;
    Op = CommuteVectorShuffle(Op, V1, V2, PermMask, DAG);
    if (V2IsSplat) {
      // V2 is a splat, so the mask may be malformed. That is, it may point
      // to any V2 element. The instruction selectior won't like this. Get
      // a corrected mask and commute to form a proper MOVS{S|D}.
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      SDValue NewMask = getMOVLMask(NumElems, DAG);
        Op = DAG.getNode(ISD::VECTOR_SHUFFLE, VT, V1, V2, NewMask);
    return Op;
  if (X86::isUNPCKL_v_undef_Mask(PermMask.getNode()) ||
      X86::isUNPCKH_v_undef_Mask(PermMask.getNode()) ||
      X86::isUNPCKLMask(PermMask.getNode()) ||
      X86::isUNPCKHMask(PermMask.getNode()))
  if (V2IsSplat) {
    // Normalize mask so all entries that point to V2 points to its first
    // element then try to match unpck{h|l} again. If match, return a
    // new vector_shuffle with the corrected mask.
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    SDValue NewMask = NormalizeMask(PermMask, DAG);
    if (NewMask.getNode() != PermMask.getNode()) {
      if (X86::isUNPCKLMask(PermMask.getNode(), true)) {
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        SDValue NewMask = getUnpacklMask(NumElems, DAG);
        return DAG.getNode(ISD::VECTOR_SHUFFLE, VT, V1, V2, NewMask);
      } else if (X86::isUNPCKHMask(PermMask.getNode(), true)) {
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        SDValue NewMask = getUnpackhMask(NumElems, DAG);
        return DAG.getNode(ISD::VECTOR_SHUFFLE, VT, V1, V2, NewMask);
      }
    }
  }

  // Normalize the node to match x86 shuffle ops if needed
  if (V2.getOpcode() != ISD::UNDEF && isCommutedSHUFP(PermMask.getNode()))
      Op = CommuteVectorShuffle(Op, V1, V2, PermMask, DAG);

  if (Commuted) {
    // Commute is back and try unpck* again.
    Op = CommuteVectorShuffle(Op, V1, V2, PermMask, DAG);
    if (X86::isUNPCKL_v_undef_Mask(PermMask.getNode()) ||
        X86::isUNPCKH_v_undef_Mask(PermMask.getNode()) ||
        X86::isUNPCKLMask(PermMask.getNode()) ||
        X86::isUNPCKHMask(PermMask.getNode()))
  // Try PSHUF* first, then SHUFP*.
  // MMX doesn't have PSHUFD but it does have PSHUFW. While it's theoretically
  // possible to shuffle a v2i32 using PSHUFW, that's not yet implemented.
  if (isMMX && NumElems == 4 && X86::isPSHUFDMask(PermMask.getNode())) {
    if (V2.getOpcode() != ISD::UNDEF)
      return DAG.getNode(ISD::VECTOR_SHUFFLE, VT, V1,
                         DAG.getNode(ISD::UNDEF, VT), PermMask);
    return Op;
  }

  if (!isMMX) {
    if (Subtarget->hasSSE2() &&
        (X86::isPSHUFDMask(PermMask.getNode()) ||
         X86::isPSHUFHWMask(PermMask.getNode()) ||
         X86::isPSHUFLWMask(PermMask.getNode()))) {
      if (VT == MVT::v4f32) {
        RVT = MVT::v4i32;
        Op = DAG.getNode(ISD::VECTOR_SHUFFLE, RVT,
                         DAG.getNode(ISD::BIT_CONVERT, RVT, V1),
                         DAG.getNode(ISD::UNDEF, RVT), PermMask);
      } else if (V2.getOpcode() != ISD::UNDEF)
        Op = DAG.getNode(ISD::VECTOR_SHUFFLE, RVT, V1,
                         DAG.getNode(ISD::UNDEF, RVT), PermMask);
      if (RVT != VT)
        Op = DAG.getNode(ISD::BIT_CONVERT, VT, Op);
    if (X86::isSHUFPMask(PermMask.getNode()) ||
        (V2.getOpcode() == ISD::UNDEF && X86::isPSHUFDMask(PermMask.getNode())))
  // Handle v8i16 specifically since SSE can do byte extraction and insertion.
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    SDValue NewOp = LowerVECTOR_SHUFFLEv8i16(V1, V2, PermMask, DAG, *this);
  // Handle all 4 wide cases with a number of shuffles except for MMX.
  if (NumElems == 4 && !isMMX)
    return LowerVECTOR_SHUFFLE_4wide(V1, V2, PermMask, VT, DAG);
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  return SDValue();
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SDValue
X86TargetLowering::LowerEXTRACT_VECTOR_ELT_SSE4(SDValue Op,
                                                SelectionDAG &DAG) {
  MVT VT = Op.getValueType();
  if (VT.getSizeInBits() == 8) {
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    SDValue Extract = DAG.getNode(X86ISD::PEXTRB, MVT::i32,
                                    Op.getOperand(0), Op.getOperand(1));
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    SDValue Assert  = DAG.getNode(ISD::AssertZext, MVT::i32, Extract,
                                    DAG.getValueType(VT));
    return DAG.getNode(ISD::TRUNCATE, VT, Assert);
  } else if (VT.getSizeInBits() == 16) {
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    SDValue Extract = DAG.getNode(X86ISD::PEXTRW, MVT::i32,
                                    Op.getOperand(0), Op.getOperand(1));
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    SDValue Assert  = DAG.getNode(ISD::AssertZext, MVT::i32, Extract,
                                    DAG.getValueType(VT));
    return DAG.getNode(ISD::TRUNCATE, VT, Assert);
  } else if (VT == MVT::f32) {
    // EXTRACTPS outputs to a GPR32 register which will require a movd to copy
    // the result back to FR32 register. It's only worth matching if the
    // result has a single use which is a store or a bitcast to i32.
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      return SDValue();
    if (User->getOpcode() != ISD::STORE &&
        (User->getOpcode() != ISD::BIT_CONVERT ||
         User->getValueType(0) != MVT::i32))
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      return SDValue();
    SDValue Extract = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, MVT::i32,
                    DAG.getNode(ISD::BIT_CONVERT, MVT::v4i32, Op.getOperand(0)),
                                    Op.getOperand(1));
    return DAG.getNode(ISD::BIT_CONVERT, MVT::f32, Extract);
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  return SDValue();
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SDValue
X86TargetLowering::LowerEXTRACT_VECTOR_ELT(SDValue Op, SelectionDAG &DAG) {
  if (!isa<ConstantSDNode>(Op.getOperand(1)))
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    return SDValue();
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    SDValue Res = LowerEXTRACT_VECTOR_ELT_SSE4(Op, DAG);
  MVT VT = Op.getValueType();
  if (VT.getSizeInBits() == 16) {
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    SDValue Vec = Op.getOperand(0);
    unsigned Idx = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
    if (Idx == 0)
      return DAG.getNode(ISD::TRUNCATE, MVT::i16,
                         DAG.getNode(ISD::EXTRACT_VECTOR_ELT, MVT::i32,
                                 DAG.getNode(ISD::BIT_CONVERT, MVT::v4i32, Vec),
                                     Op.getOperand(1)));
    // Transform it so it match pextrw which produces a 32-bit result.
    MVT EVT = (MVT::SimpleValueType)(VT.getSimpleVT()+1);
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    SDValue Extract = DAG.getNode(X86ISD::PEXTRW, EVT,
                                    Op.getOperand(0), Op.getOperand(1));
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    SDValue Assert  = DAG.getNode(ISD::AssertZext, EVT, Extract,
                                    DAG.getValueType(VT));
    return DAG.getNode(ISD::TRUNCATE, VT, Assert);
  } else if (VT.getSizeInBits() == 32) {
    unsigned Idx = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
    if (Idx == 0)
      return Op;
    // SHUFPS the element to the lowest double word, then movss.
    MVT MaskVT = MVT::getIntVectorWithNumElements(4);
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    SmallVector<SDValue, 8> IdxVec;
      push_back(DAG.getConstant(Idx, MaskVT.getVectorElementType()));
      push_back(DAG.getNode(ISD::UNDEF, MaskVT.getVectorElementType()));
      push_back(DAG.getNode(ISD::UNDEF, MaskVT.getVectorElementType()));
      push_back(DAG.getNode(ISD::UNDEF, MaskVT.getVectorElementType()));
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    SDValue Mask = DAG.getNode(ISD::BUILD_VECTOR, MaskVT,
                                 &IdxVec[0], IdxVec.size());
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    SDValue Vec = Op.getOperand(0);
    Vec = DAG.getNode(ISD::VECTOR_SHUFFLE, Vec.getValueType(),
                      Vec, DAG.getNode(ISD::UNDEF, Vec.getValueType()), Mask);
    return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, VT, Vec,
                       DAG.getIntPtrConstant(0));
  } else if (VT.getSizeInBits() == 64) {
    // FIXME: .td only matches this for <2 x f64>, not <2 x i64> on 32b
    // FIXME: seems like this should be unnecessary if mov{h,l}pd were taught
    //        to match extract_elt for f64.
    unsigned Idx = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
    if (Idx == 0)
      return Op;

    // UNPCKHPD the element to the lowest double word, then movsd.
    // Note if the lower 64 bits of the result of the UNPCKHPD is then stored
    // to a f64mem, the whole operation is folded into a single MOVHPDmr.
    MVT MaskVT = MVT::getIntVectorWithNumElements(2);
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    SmallVector<SDValue, 8> IdxVec;
    IdxVec.push_back(DAG.getConstant(1, MaskVT.getVectorElementType()));
      push_back(DAG.getNode(ISD::UNDEF, MaskVT.getVectorElementType()));
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    SDValue Mask = DAG.getNode(ISD::BUILD_VECTOR, MaskVT,
                                 &IdxVec[0], IdxVec.size());
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    SDValue Vec = Op.getOperand(0);
    Vec = DAG.getNode(ISD::VECTOR_SHUFFLE, Vec.getValueType(),
                      Vec, DAG.getNode(ISD::UNDEF, Vec.getValueType()), Mask);
    return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, VT, Vec,
                       DAG.getIntPtrConstant(0));
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  return SDValue();
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SDValue
X86TargetLowering::LowerINSERT_VECTOR_ELT_SSE4(SDValue Op, SelectionDAG &DAG){
  MVT VT = Op.getValueType();
  MVT EVT = VT.getVectorElementType();
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  SDValue N0 = Op.getOperand(0);
  SDValue N1 = Op.getOperand(1);
  SDValue N2 = Op.getOperand(2);
  if ((EVT.getSizeInBits() == 8 || EVT.getSizeInBits() == 16) &&
      isa<ConstantSDNode>(N2)) {
    unsigned Opc = (EVT.getSizeInBits() == 8) ? X86ISD::PINSRB
                                                  : X86ISD::PINSRW;
    // Transform it so it match pinsr{b,w} which expects a GR32 as its second
    // argument.
    if (N1.getValueType() != MVT::i32)
      N1 = DAG.getNode(ISD::ANY_EXTEND, MVT::i32, N1);
    if (N2.getValueType() != MVT::i32)
      N2 = DAG.getIntPtrConstant(cast<ConstantSDNode>(N2)->getZExtValue());
    return DAG.getNode(Opc, VT, N0, N1, N2);
  } else if (EVT == MVT::f32 && isa<ConstantSDNode>(N2)) {
    // Bits [7:6] of the constant are the source select.  This will always be
    //  zero here.  The DAG Combiner may combine an extract_elt index into these
    //  bits.  For example (insert (extract, 3), 2) could be matched by putting
    //  the '3' into bits [7:6] of X86ISD::INSERTPS.
    // Bits [5:4] of the constant are the destination select.  This is the 
    //  value of the incoming immediate.
    // Bits [3:0] of the constant are the zero mask.  The DAG Combiner may 
    //   combine either bitwise AND or insert of float 0.0 to set these bits.
    N2 = DAG.getIntPtrConstant(cast<ConstantSDNode>(N2)->getZExtValue() << 4);
    return DAG.getNode(X86ISD::INSERTPS, VT, N0, N1, N2);
  }
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  return SDValue();
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SDValue
X86TargetLowering::LowerINSERT_VECTOR_ELT(SDValue Op, SelectionDAG &DAG) {
  MVT VT = Op.getValueType();
  MVT EVT = VT.getVectorElementType();

  if (Subtarget->hasSSE41())
    return LowerINSERT_VECTOR_ELT_SSE4(Op, DAG);

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    return SDValue();
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  SDValue N0 = Op.getOperand(0);
  SDValue N1 = Op.getOperand(1);
  SDValue N2 = Op.getOperand(2);
  if (EVT.getSizeInBits() == 16) {
    // Transform it so it match pinsrw which expects a 16-bit value in a GR32
    // as its second argument.
    if (N1.getValueType() != MVT::i32)
      N1 = DAG.getNode(ISD::ANY_EXTEND, MVT::i32, N1);
    if (N2.getValueType() != MVT::i32)
      N2 = DAG.getIntPtrConstant(cast<ConstantSDNode>(N2)->getZExtValue());
    return DAG.getNode(X86ISD::PINSRW, VT, N0, N1, N2);
  }
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  return SDValue();
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SDValue
X86TargetLowering::LowerSCALAR_TO_VECTOR(SDValue Op, SelectionDAG &DAG) {
  if (Op.getValueType() == MVT::v2f32)
    return DAG.getNode(ISD::BIT_CONVERT, MVT::v2f32,
                       DAG.getNode(ISD::SCALAR_TO_VECTOR, MVT::v2i32,
                                   DAG.getNode(ISD::BIT_CONVERT, MVT::i32,
                                               Op.getOperand(0))));

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  SDValue AnyExt = DAG.getNode(ISD::ANY_EXTEND, MVT::i32, Op.getOperand(0));
  MVT VT = MVT::v2i32;
  switch (Op.getValueType().getSimpleVT()) {
  default: break;
  case MVT::v16i8:
  case MVT::v8i16:
    VT = MVT::v4i32;
    break;
  }
  return DAG.getNode(ISD::BIT_CONVERT, Op.getValueType(),
                     DAG.getNode(ISD::SCALAR_TO_VECTOR, VT, AnyExt));
// ConstantPool, JumpTable, GlobalAddress, and ExternalSymbol are lowered as
// their target countpart wrapped in the X86ISD::Wrapper node. Suppose N is
// one of the above mentioned nodes. It has to be wrapped because otherwise
// Select(N) returns N. So the raw TargetGlobalAddress nodes, etc. can only
// be used to form addressing mode. These wrapped nodes will be selected
// into MOV32ri.
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SDValue
X86TargetLowering::LowerConstantPool(SDValue Op, SelectionDAG &DAG) {
  ConstantPoolSDNode *CP = cast<ConstantPoolSDNode>(Op);
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  SDValue Result = DAG.getTargetConstantPool(CP->getConstVal(),
                                               getPointerTy(),
                                               CP->getAlignment());
  Result = DAG.getNode(X86ISD::Wrapper, getPointerTy(), Result);
  // With PIC, the address is actually $g + Offset.
  if (getTargetMachine().getRelocationModel() == Reloc::PIC_ &&
      !Subtarget->isPICStyleRIPRel()) {
    Result = DAG.getNode(ISD::ADD, getPointerTy(),
                         DAG.getNode(X86ISD::GlobalBaseReg, getPointerTy()),
                         Result);
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SDValue
X86TargetLowering::LowerGlobalAddress(const GlobalValue *GV,
  bool IsPic = getTargetMachine().getRelocationModel() == Reloc::PIC_;
  bool ExtraLoadRequired =
    Subtarget->GVRequiresExtraLoad(GV, getTargetMachine(), false);

  // Create the TargetGlobalAddress node, folding in the constant
  // offset if it is legal.
  SDValue Result;
  if (!IsPic && !ExtraLoadRequired && isInt32(Offset)) {
    Result = DAG.getTargetGlobalAddress(GV, getPointerTy(), Offset);
    Offset = 0;
  } else
    Result = DAG.getTargetGlobalAddress(GV, getPointerTy(), 0);
  Result = DAG.getNode(X86ISD::Wrapper, getPointerTy(), Result);
  // With PIC, the address is actually $g + Offset.
  if (IsPic && !Subtarget->isPICStyleRIPRel()) {
    Result = DAG.getNode(ISD::ADD, getPointerTy(),
                         DAG.getNode(X86ISD::GlobalBaseReg, getPointerTy()),
                         Result);
  
  // For Darwin & Mingw32, external and weak symbols are indirect, so we want to
  // load the value at address GV, not the value of GV itself. This means that
  // the GlobalAddress must be in the base or index register of the address, not
  // the GV offset field. Platform check is inside GVRequiresExtraLoad() call
  // The same applies for external symbols during PIC codegen
    Result = DAG.getLoad(getPointerTy(), DAG.getEntryNode(), Result,
                         PseudoSourceValue::getGOT(), 0);
  // If there was a non-zero offset that we didn't fold, create an explicit
  // addition for it.
  if (Offset != 0)
    Result = DAG.getNode(ISD::ADD, getPointerTy(), Result,
                         DAG.getConstant(Offset, getPointerTy()));

SDValue
X86TargetLowering::LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) {
  const GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
  int64_t Offset = cast<GlobalAddressSDNode>(Op)->getOffset();
  return LowerGlobalAddress(GV, Offset, DAG);
// Lower ISD::GlobalTLSAddress using the "general dynamic" model, 32 bit
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static SDValue
LowerToTLSGeneralDynamicModel32(GlobalAddressSDNode *GA, SelectionDAG &DAG,
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  SDValue InFlag;
  SDValue Chain = DAG.getCopyToReg(DAG.getEntryNode(), X86::EBX,
                                     DAG.getNode(X86ISD::GlobalBaseReg,
                                                 PtrVT), InFlag);
  InFlag = Chain.getValue(1);

  // emit leal symbol@TLSGD(,%ebx,1), %eax
  SDVTList NodeTys = DAG.getVTList(PtrVT, MVT::Other, MVT::Flag);
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  SDValue TGA = DAG.getTargetGlobalAddress(GA->getGlobal(),
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  SDValue Ops[] = { Chain,  TGA, InFlag };
  SDValue Result = DAG.getNode(X86ISD::TLSADDR, NodeTys, Ops, 3);
  InFlag = Result.getValue(2);
  Chain = Result.getValue(1);

  // call ___tls_get_addr. This function receives its argument in
  // the register EAX.
  Chain = DAG.getCopyToReg(Chain, X86::EAX, Result, InFlag);
  InFlag = Chain.getValue(1);

  NodeTys = DAG.getVTList(MVT::Other, MVT::Flag);
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  SDValue Ops1[] = { Chain,
                      DAG.getTargetExternalSymbol("___tls_get_addr",
                                                  PtrVT),
                      DAG.getRegister(X86::EAX, PtrVT),
                      DAG.getRegister(X86::EBX, PtrVT),
                      InFlag };
  Chain = DAG.getNode(X86ISD::CALL, NodeTys, Ops1, 5);
  InFlag = Chain.getValue(1);

  return DAG.getCopyFromReg(Chain, X86::EAX, PtrVT, InFlag);
}

// Lower ISD::GlobalTLSAddress using the "general dynamic" model, 64 bit
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static SDValue
LowerToTLSGeneralDynamicModel64(GlobalAddressSDNode *GA, SelectionDAG &DAG,
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  SDValue InFlag, Chain;

  // emit leaq symbol@TLSGD(%rip), %rdi
  SDVTList NodeTys = DAG.getVTList(PtrVT, MVT::Other, MVT::Flag);
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  SDValue TGA = DAG.getTargetGlobalAddress(GA->getGlobal(),
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  SDValue Ops[]  = { DAG.getEntryNode(), TGA};
  SDValue Result = DAG.getNode(X86ISD::TLSADDR, NodeTys, Ops, 2);
  // call __tls_get_addr. This function receives its argument in
  // the register RDI.
  Chain = DAG.getCopyToReg(Chain, X86::RDI, Result, InFlag);
  InFlag = Chain.getValue(1);

  NodeTys = DAG.getVTList(MVT::Other, MVT::Flag);
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  SDValue Ops1[] = { Chain,
                      DAG.getTargetExternalSymbol("__tls_get_addr",
                                                  PtrVT),
                      DAG.getRegister(X86::RDI, PtrVT),
                      InFlag };
  Chain = DAG.getNode(X86ISD::CALL, NodeTys, Ops1, 4);
  InFlag = Chain.getValue(1);

  return DAG.getCopyFromReg(Chain, X86::RAX, PtrVT, InFlag);
}

// Lower ISD::GlobalTLSAddress using the "initial exec" (for no-pic) or
// "local exec" model.
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static SDValue LowerToTLSExecModel(GlobalAddressSDNode *GA, SelectionDAG &DAG,
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  SDValue ThreadPointer = DAG.getNode(X86ISD::THREAD_POINTER, PtrVT);
  // emit "addl x@ntpoff,%eax" (local exec) or "addl x@indntpoff,%eax" (initial
  // exec)
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  SDValue TGA = DAG.getTargetGlobalAddress(GA->getGlobal(),
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  SDValue Offset = DAG.getNode(X86ISD::Wrapper, PtrVT, TGA);

  if (GA->getGlobal()->isDeclaration()) // initial exec TLS model
    Offset = DAG.getLoad(PtrVT, DAG.getEntryNode(), Offset,
                         PseudoSourceValue::getGOT(), 0);
  // The address of the thread local variable is the add of the thread
  // pointer with the offset of the variable.
  return DAG.getNode(ISD::ADD, PtrVT, ThreadPointer, Offset);
}

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SDValue
X86TargetLowering::LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) {
  // TODO: implement the "local dynamic" model
  // TODO: implement the "initial exec"model for pic executables
  assert(Subtarget->isTargetELF() &&
         "TLS not implemented for non-ELF targets");
  GlobalAddressSDNode *GA = cast<GlobalAddressSDNode>(Op);
  // If the relocation model is PIC, use the "General Dynamic" TLS Model,
  // otherwise use the "Local Exec"TLS Model
  if (Subtarget->is64Bit()) {
    return LowerToTLSGeneralDynamicModel64(GA, DAG, getPointerTy());
  } else {
    if (getTargetMachine().getRelocationModel() == Reloc::PIC_)
      return LowerToTLSGeneralDynamicModel32(GA, DAG, getPointerTy());
    else
      return LowerToTLSExecModel(GA, DAG, getPointerTy());
  }
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SDValue
X86TargetLowering::LowerExternalSymbol(SDValue Op, SelectionDAG &DAG) {
  const char *Sym = cast<ExternalSymbolSDNode>(Op)->getSymbol();
  SDValue Result = DAG.getTargetExternalSymbol(Sym, getPointerTy());
  Result = DAG.getNode(X86ISD::Wrapper, getPointerTy(), Result);
  // With PIC, the address is actually $g + Offset.
  if (getTargetMachine().getRelocationModel() == Reloc::PIC_ &&
      !Subtarget->isPICStyleRIPRel()) {
    Result = DAG.getNode(ISD::ADD, getPointerTy(),
                         DAG.getNode(X86ISD::GlobalBaseReg, getPointerTy()),
                         Result);
  }

  return Result;
}

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SDValue X86TargetLowering::LowerJumpTable(SDValue Op, SelectionDAG &DAG) {
  JumpTableSDNode *JT = cast<JumpTableSDNode>(Op);
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  SDValue Result = DAG.getTargetJumpTable(JT->getIndex(), getPointerTy());
  Result = DAG.getNode(X86ISD::Wrapper, getPointerTy(), Result);
  // With PIC, the address is actually $g + Offset.
  if (getTargetMachine().getRelocationModel() == Reloc::PIC_ &&
      !Subtarget->isPICStyleRIPRel()) {
    Result = DAG.getNode(ISD::ADD, getPointerTy(),
                         DAG.getNode(X86ISD::GlobalBaseReg, getPointerTy()),
                         Result);
/// LowerShift - Lower SRA_PARTS and friends, which return two i32 values and
/// take a 2 x i32 value to shift plus a shift amount. 
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SDValue X86TargetLowering::LowerShift(SDValue Op, SelectionDAG &DAG) {
  assert(Op.getNumOperands() == 3 && "Not a double-shift!");
  MVT VT = Op.getValueType();
  unsigned VTBits = VT.getSizeInBits();
  bool isSRA = Op.getOpcode() == ISD::SRA_PARTS;
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  SDValue ShOpLo = Op.getOperand(0);
  SDValue ShOpHi = Op.getOperand(1);
  SDValue ShAmt  = Op.getOperand(2);
  SDValue Tmp1 = isSRA ?
    DAG.getNode(ISD::SRA, VT, ShOpHi, DAG.getConstant(VTBits - 1, MVT::i8)) :
    DAG.getConstant(0, VT);
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  SDValue Tmp2, Tmp3;
  if (Op.getOpcode() == ISD::SHL_PARTS) {
    Tmp2 = DAG.getNode(X86ISD::SHLD, VT, ShOpHi, ShOpLo, ShAmt);
    Tmp3 = DAG.getNode(ISD::SHL, VT, ShOpLo, ShAmt);
    Tmp2 = DAG.getNode(X86ISD::SHRD, VT, ShOpLo, ShOpHi, ShAmt);
    Tmp3 = DAG.getNode(isSRA ? ISD::SRA : ISD::SRL, VT, ShOpHi, ShAmt);
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  SDValue AndNode = DAG.getNode(ISD::AND, MVT::i8, ShAmt,
                                  DAG.getConstant(VTBits, MVT::i8));
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  SDValue Cond = DAG.getNode(X86ISD::CMP, VT,
                               AndNode, DAG.getConstant(0, MVT::i8));

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  SDValue Hi, Lo;
  SDValue CC = DAG.getConstant(X86::COND_NE, MVT::i8);
  SDValue Ops0[4] = { Tmp2, Tmp3, CC, Cond };
  SDValue Ops1[4] = { Tmp3, Tmp1, CC, Cond };
  if (Op.getOpcode() == ISD::SHL_PARTS) {
    Hi = DAG.getNode(X86ISD::CMOV, VT, Ops0, 4);
    Lo = DAG.getNode(X86ISD::CMOV, VT, Ops1, 4);
    Lo = DAG.getNode(X86ISD::CMOV, VT, Ops0, 4);
    Hi = DAG.getNode(X86ISD::CMOV, VT, Ops1, 4);
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  SDValue Ops[2] = { Lo, Hi };
  return DAG.getMergeValues(Ops, 2);
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SDValue X86TargetLowering::LowerSINT_TO_FP(SDValue Op, SelectionDAG &DAG) {
  MVT SrcVT = Op.getOperand(0).getValueType();
  assert(SrcVT.getSimpleVT() <= MVT::i64 && SrcVT.getSimpleVT() >= MVT::i16 &&
         "Unknown SINT_TO_FP to lower!");
  
  // These are really Legal; caller falls through into that case.
  if (SrcVT == MVT::i32 && isScalarFPTypeInSSEReg(Op.getValueType()))
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    return SDValue();
  if (SrcVT == MVT::i64 && Op.getValueType() != MVT::f80 && 
      Subtarget->is64Bit())
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    return SDValue();
  unsigned Size = SrcVT.getSizeInBits()/8;
  MachineFunction &MF = DAG.getMachineFunction();
  int SSFI = MF.getFrameInfo()->CreateStackObject(Size, Size);
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  SDValue StackSlot = DAG.getFrameIndex(SSFI, getPointerTy());
  SDValue Chain = DAG.getStore(DAG.getEntryNode(), Op.getOperand(0),
                                 PseudoSourceValue::getFixedStack(SSFI), 0);
  bool useSSE = isScalarFPTypeInSSEReg(Op.getValueType());
    Tys = DAG.getVTList(MVT::f64, MVT::Other, MVT::Flag);
  else
    Tys = DAG.getVTList(Op.getValueType(), MVT::Other);
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  SmallVector<SDValue, 8> Ops;
  Ops.push_back(Chain);
  Ops.push_back(StackSlot);
  Ops.push_back(DAG.getValueType(SrcVT));
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  SDValue Result = DAG.getNode(useSSE ? X86ISD::FILD_FLAG : X86ISD::FILD,
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    SDValue InFlag = Result.getValue(2);

    // FIXME: Currently the FST is flagged to the FILD_FLAG. This
    // shouldn't be necessary except that RFP cannot be live across
    // multiple blocks. When stackifier is fixed, they can be uncoupled.
    MachineFunction &MF = DAG.getMachineFunction();
    int SSFI = MF.getFrameInfo()->CreateStackObject(8, 8);
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    SDValue StackSlot = DAG.getFrameIndex(SSFI, getPointerTy());
    Tys = DAG.getVTList(MVT::Other);
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    SmallVector<SDValue, 8> Ops;
    Ops.push_back(Chain);
    Ops.push_back(DAG.getValueType(Op.getValueType()));
    Ops.push_back(InFlag);
    Chain = DAG.getNode(X86ISD::FST, Tys, &Ops[0], Ops.size());
    Result = DAG.getLoad(Op.getValueType(), Chain, StackSlot,
                         PseudoSourceValue::getFixedStack(SSFI), 0);
SDValue X86TargetLowering::LowerUINT_TO_FP(SDValue Op, SelectionDAG &DAG) {
  MVT SrcVT = Op.getOperand(0).getValueType();
  assert(SrcVT.getSimpleVT() == MVT::i64 && "Unknown UINT_TO_FP to lower!");
  
  // We only handle SSE2 f64 target here; caller can handle the rest.
  if (Op.getValueType() != MVT::f64 || !X86ScalarSSEf64)
    return SDValue();
  
  // This algorithm is not obvious.  Here it is in C code, more or less:
/*
 double uint64_to_double( uint32_t hi, uint32_t lo )
  {
    static const __m128i exp = { 0x4330000045300000ULL, 0 };
    static const __m128d bias = { 0x1.0p84, 0x1.0p52 };

    // copy ints to xmm registers
    __m128i xh = _mm_cvtsi32_si128( hi );
    __m128i xl = _mm_cvtsi32_si128( lo );

    // combine into low half of a single xmm register
    __m128i x = _mm_unpacklo_epi32( xh, xl );
    __m128d d;
    double sd;

    // merge in appropriate exponents to give the integer bits the 
    // right magnitude
    x = _mm_unpacklo_epi32( x, exp );

    // subtract away the biases to deal with the IEEE-754 double precision
    // implicit 1
    d = _mm_sub_pd( (__m128d) x, bias );

    // All conversions up to here are exact. The correctly rounded result is 
    // calculated using the
    // current rounding mode using the following horizontal add.
    d = _mm_add_sd( d, _mm_unpackhi_pd( d, d ) );
    _mm_store_sd( &sd, d );   //since we are returning doubles in XMM, this
    // store doesn't really need to be here (except maybe to zero the other
    // double)
  // Build some magic constants.
  std::vector<Constant*>CV0;
  CV0.push_back(ConstantInt::get(APInt(32, 0x45300000)));
  CV0.push_back(ConstantInt::get(APInt(32, 0x43300000)));
  CV0.push_back(ConstantInt::get(APInt(32, 0)));
  CV0.push_back(ConstantInt::get(APInt(32, 0)));
  Constant *C0 = ConstantVector::get(CV0);
  SDValue CPIdx0 = DAG.getConstantPool(C0, getPointerTy(), 4);

  std::vector<Constant*>CV1;
  CV1.push_back(ConstantFP::get(APFloat(APInt(64, 0x4530000000000000ULL))));
  CV1.push_back(ConstantFP::get(APFloat(APInt(64, 0x4330000000000000ULL))));
  Constant *C1 = ConstantVector::get(CV1);
  SDValue CPIdx1 = DAG.getConstantPool(C1, getPointerTy(), 4);

  SmallVector<SDValue, 4> MaskVec;
  MaskVec.push_back(DAG.getConstant(0, MVT::i32));
  MaskVec.push_back(DAG.getConstant(4, MVT::i32));
  MaskVec.push_back(DAG.getConstant(1, MVT::i32));
  MaskVec.push_back(DAG.getConstant(5, MVT::i32));
  SDValue UnpcklMask = DAG.getNode(ISD::BUILD_VECTOR, MVT::v4i32, &MaskVec[0],
                                   MaskVec.size());
  SmallVector<SDValue, 4> MaskVec2;
  MaskVec2.push_back(DAG.getConstant(1, MVT::i32));
  MaskVec2.push_back(DAG.getConstant(0, MVT::i32));
  SDValue ShufMask = DAG.getNode(ISD::BUILD_VECTOR, MVT::v2i32, &MaskVec2[0],
                                 MaskVec2.size());

  SDValue XR1 = DAG.getNode(ISD::SCALAR_TO_VECTOR, MVT::v4i32,
                            DAG.getNode(ISD::EXTRACT_ELEMENT, MVT::i32,
                                        Op.getOperand(0),
                                        DAG.getIntPtrConstant(1)));
  SDValue XR2 = DAG.getNode(ISD::SCALAR_TO_VECTOR, MVT::v4i32,
                            DAG.getNode(ISD::EXTRACT_ELEMENT, MVT::i32,
                                        Op.getOperand(0),
                                        DAG.getIntPtrConstant(0)));
  SDValue Unpck1 = DAG.getNode(ISD::VECTOR_SHUFFLE, MVT::v4i32,
                                XR1, XR2, UnpcklMask);
  SDValue CLod0 = DAG.getLoad(MVT::v4i32, DAG.getEntryNode(), CPIdx0,
                         PseudoSourceValue::getConstantPool(), 0, false, 16);
  SDValue Unpck2 = DAG.getNode(ISD::VECTOR_SHUFFLE, MVT::v4i32,
                                Unpck1, CLod0, UnpcklMask);
  SDValue XR2F = DAG.getNode(ISD::BIT_CONVERT, MVT::v2f64, Unpck2);
  SDValue CLod1 = DAG.getLoad(MVT::v2f64, CLod0.getValue(1), CPIdx1,
                         PseudoSourceValue::getConstantPool(), 0, false, 16);
  SDValue Sub = DAG.getNode(ISD::FSUB, MVT::v2f64, XR2F, CLod1);
  // Add the halves; easiest way is to swap them into another reg first.
  SDValue Shuf = DAG.getNode(ISD::VECTOR_SHUFFLE, MVT::v2f64,
                             Sub, Sub, ShufMask);
  SDValue Add = DAG.getNode(ISD::FADD, MVT::v2f64, Shuf, Sub);
  return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, MVT::f64, Add,
                     DAG.getIntPtrConstant(0));
}

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std::pair<SDValue,SDValue> X86TargetLowering::
FP_TO_SINTHelper(SDValue Op, SelectionDAG &DAG) {
  assert(Op.getValueType().getSimpleVT() <= MVT::i64 &&
         Op.getValueType().getSimpleVT() >= MVT::i16 &&
  // These are really Legal.
  if (Op.getValueType() == MVT::i32 && 
      isScalarFPTypeInSSEReg(Op.getOperand(0).getValueType()))
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    return std::make_pair(SDValue(), SDValue());
  if (Subtarget->is64Bit() &&
      Op.getValueType() == MVT::i64 &&
      Op.getOperand(0).getValueType() != MVT::f80)
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    return std::make_pair(SDValue(), SDValue());
  // We lower FP->sint64 into FISTP64, followed by a load, all to a temporary
  // stack slot.
  MachineFunction &MF = DAG.getMachineFunction();
  unsigned MemSize = Op.getValueType().getSizeInBits()/8;
  int SSFI = MF.getFrameInfo()->CreateStackObject(MemSize, MemSize);
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  SDValue StackSlot = DAG.getFrameIndex(SSFI, getPointerTy());
  switch (Op.getValueType().getSimpleVT()) {
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  default: assert(0 && "Invalid FP_TO_SINT to lower!");
  case MVT::i16: Opc = X86ISD::FP_TO_INT16_IN_MEM; break;
  case MVT::i32: Opc = X86ISD::FP_TO_INT32_IN_MEM; break;
  case MVT::i64: Opc = X86ISD::FP_TO_INT64_IN_MEM; break;
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  SDValue Chain = DAG.getEntryNode();
  SDValue Value = Op.getOperand(0);
  if (isScalarFPTypeInSSEReg(Op.getOperand(0).getValueType())) {
    assert(Op.getValueType() == MVT::i64 && "Invalid FP_TO_SINT to lower!");
    Chain = DAG.getStore(Chain, Value, StackSlot,
                         PseudoSourceValue::getFixedStack(SSFI), 0);
    SDVTList Tys = DAG.getVTList(Op.getOperand(0).getValueType(), MVT::Other);
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    SDValue Ops[] = {
      Chain, StackSlot, DAG.getValueType(Op.getOperand(0).getValueType())
    };
    Value = DAG.getNode(X86ISD::FLD, Tys, Ops, 3);
    Chain = Value.getValue(1);
    SSFI = MF.getFrameInfo()->CreateStackObject(MemSize, MemSize);
    StackSlot = DAG.getFrameIndex(SSFI, getPointerTy());
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  // Build the FP_TO_INT*_IN_MEM
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  SDValue Ops[] = { Chain, Value, StackSlot };
  SDValue FIST = DAG.getNode(Opc, MVT::Other, Ops, 3);
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  return std::make_pair(FIST, StackSlot);
}

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SDValue X86TargetLowering::LowerFP_TO_SINT(SDValue Op, SelectionDAG &DAG) {
  std::pair<SDValue,SDValue> Vals = FP_TO_SINTHelper(Op, DAG);
  SDValue FIST = Vals.first, StackSlot = Vals.second;
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  // Load the result.
  return DAG.getLoad(Op.getValueType(), FIST, StackSlot, NULL, 0);
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SDNode *X86TargetLowering::ExpandFP_TO_SINT(SDNode *N, SelectionDAG &DAG) {
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  std::pair<SDValue,SDValue> Vals = FP_TO_SINTHelper(SDValue(N, 0), DAG);
  SDValue FIST = Vals.first, StackSlot = Vals.second;

  MVT VT = N->getValueType(0);

  // Return a load from the stack slot.
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  SDValue Res = DAG.getLoad(VT, FIST, StackSlot, NULL, 0);
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  // Use MERGE_VALUES to drop the chain result value and get a node with one
  // result.  This requires turning off getMergeValues simplification, since
  // otherwise it will give us Res back.
  return DAG.getMergeValues(&Res, 1, false).getNode();
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SDValue X86TargetLowering::LowerFABS(SDValue Op, SelectionDAG &DAG) {
  MVT VT = Op.getValueType();
  MVT EltVT = VT;
  if (VT.isVector())
    EltVT = VT.getVectorElementType();
    Constant *C = ConstantFP::get(APFloat(APInt(64, ~(1ULL << 63))));
    Constant *C = ConstantFP::get(APFloat(APInt(32, ~(1U << 31))));
    CV.push_back(C);
    CV.push_back(C);
    CV.push_back(C);
    CV.push_back(C);
  Constant *C = ConstantVector::get(CV);
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  SDValue CPIdx = DAG.getConstantPool(C, getPointerTy(), 4);
  SDValue Mask = DAG.getLoad(VT, DAG.getEntryNode(), CPIdx,
                               PseudoSourceValue::getConstantPool(), 0,
  return DAG.getNode(X86ISD::FAND, VT, Op.getOperand(0), Mask);
}

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SDValue X86TargetLowering::LowerFNEG(SDValue Op, SelectionDAG &DAG) {
  MVT VT = Op.getValueType();
  MVT EltVT = VT;
  unsigned EltNum = 1;
  if (VT.isVector()) {
    EltVT = VT.getVectorElementType();
    EltNum = VT.getVectorNumElements();
    Constant *C = ConstantFP::get(APFloat(APInt(64, 1ULL << 63)));
    Constant *C = ConstantFP::get(APFloat(APInt(32, 1U << 31)));
    CV.push_back(C);
    CV.push_back(C);
    CV.push_back(C);
    CV.push_back(C);
  Constant *C = ConstantVector::get(CV);
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  SDValue CPIdx = DAG.getConstantPool(C, getPointerTy(), 4);
  SDValue Mask = DAG.getLoad(VT, DAG.getEntryNode(), CPIdx,
                               PseudoSourceValue::getConstantPool(), 0,
  if (VT.isVector()) {
    return DAG.getNode(ISD::BIT_CONVERT, VT,
                       DAG.getNode(ISD::XOR, MVT::v2i64,
                    DAG.getNode(ISD::BIT_CONVERT, MVT::v2i64, Op.getOperand(0)),
                    DAG.getNode(ISD::BIT_CONVERT, MVT::v2i64, Mask)));
  } else {
    return DAG.getNode(X86ISD::FXOR, VT, Op.getOperand(0), Mask);
  }
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SDValue X86TargetLowering::LowerFCOPYSIGN(SDValue Op, SelectionDAG &DAG) {
  SDValue Op0 = Op.getOperand(0);
  SDValue Op1 = Op.getOperand(1);
  MVT VT = Op.getValueType();
  MVT SrcVT = Op1.getValueType();

  // If second operand is smaller, extend it first.
  if (SrcVT.bitsLT(VT)) {
    Op1 = DAG.getNode(ISD::FP_EXTEND, VT, Op1);
    SrcVT = VT;
  }
  // And if it is bigger, shrink it first.
  if (SrcVT.bitsGT(VT)) {
    Op1 = DAG.getNode(ISD::FP_ROUND, VT, Op1, DAG.getIntPtrConstant(1));
    SrcVT = VT;
  }

  // At this point the operands and the result should have the same
  // type, and that won't be f80 since that is not custom lowered.
  // First get the sign bit of second operand.
  std::vector<Constant*> CV;
  if (SrcVT == MVT::f64) {
    CV.push_back(ConstantFP::get(APFloat(APInt(64, 1ULL << 63))));
    CV.push_back(ConstantFP::get(APFloat(APInt(64, 0))));
    CV.push_back(ConstantFP::get(APFloat(APInt(32, 1U << 31))));
    CV.push_back(ConstantFP::get(APFloat(APInt(32, 0))));
    CV.push_back(ConstantFP::get(APFloat(APInt(32, 0))));
    CV.push_back(ConstantFP::get(APFloat(APInt(32, 0))));
  Constant *C = ConstantVector::get(CV);
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  SDValue CPIdx = DAG.getConstantPool(C, getPointerTy(), 4);
  SDValue Mask1 = DAG.getLoad(SrcVT, DAG.getEntryNode(), CPIdx,
                                PseudoSourceValue::getConstantPool(), 0,
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  SDValue SignBit = DAG.getNode(X86ISD::FAND, SrcVT, Op1, Mask1);

  // Shift sign bit right or left if the two operands have different types.
  if (SrcVT.bitsGT(VT)) {
    // Op0 is MVT::f32, Op1 is MVT::f64.
    SignBit = DAG.getNode(ISD::SCALAR_TO_VECTOR, MVT::v2f64, SignBit);
    SignBit = DAG.getNode(X86ISD::FSRL, MVT::v2f64, SignBit,
                          DAG.getConstant(32, MVT::i32));
    SignBit = DAG.getNode(ISD::BIT_CONVERT, MVT::v4f32, SignBit);
    SignBit = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, MVT::f32, SignBit,
                          DAG.getIntPtrConstant(0));
  // Clear first operand sign bit.
  CV.clear();
  if (VT == MVT::f64) {
    CV.push_back(ConstantFP::get(APFloat(APInt(64, ~(1ULL << 63)))));
    CV.push_back(ConstantFP::get(APFloat(APInt(64, 0))));
    CV.push_back(ConstantFP::get(APFloat(APInt(32, ~(1U << 31)))));
    CV.push_back(ConstantFP::get(APFloat(APInt(32, 0))));
    CV.push_back(ConstantFP::get(APFloat(APInt(32, 0))));
    CV.push_back(ConstantFP::get(APFloat(APInt(32, 0))));
  C = ConstantVector::get(CV);
  CPIdx = DAG.getConstantPool(C, getPointerTy(), 4);
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  SDValue Mask2 = DAG.getLoad(VT, DAG.getEntryNode(), CPIdx,
                                PseudoSourceValue::getConstantPool(), 0,
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  SDValue Val = DAG.getNode(X86ISD::FAND, VT, Op0, Mask2);

  // Or the value with the sign bit.
  return DAG.getNode(X86ISD::FOR, VT, Val, SignBit);
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SDValue X86TargetLowering::LowerSETCC(SDValue Op, SelectionDAG &DAG) {
  assert(Op.getValueType() == MVT::i8 && "SetCC type must be 8-bit integer");
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  SDValue Cond;