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      1 //===-- LegalizeDAG.cpp - Implement SelectionDAG::Legalize ----------------===//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is distributed under the University of Illinois Open Source
      6 // License. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 //
     10 // This file implements the SelectionDAG::Legalize method.
     11 //
     12 //===----------------------------------------------------------------------===//
     13 
     14 #include "llvm/Analysis/DebugInfo.h"
     15 #include "llvm/CodeGen/Analysis.h"
     16 #include "llvm/CodeGen/MachineFunction.h"
     17 #include "llvm/CodeGen/MachineJumpTableInfo.h"
     18 #include "llvm/CodeGen/SelectionDAG.h"
     19 #include "llvm/Target/TargetFrameLowering.h"
     20 #include "llvm/Target/TargetLowering.h"
     21 #include "llvm/Target/TargetData.h"
     22 #include "llvm/Target/TargetMachine.h"
     23 #include "llvm/CallingConv.h"
     24 #include "llvm/Constants.h"
     25 #include "llvm/DerivedTypes.h"
     26 #include "llvm/LLVMContext.h"
     27 #include "llvm/Support/Debug.h"
     28 #include "llvm/Support/ErrorHandling.h"
     29 #include "llvm/Support/MathExtras.h"
     30 #include "llvm/Support/raw_ostream.h"
     31 #include "llvm/ADT/DenseMap.h"
     32 #include "llvm/ADT/SmallVector.h"
     33 #include "llvm/ADT/SmallPtrSet.h"
     34 using namespace llvm;
     35 
     36 //===----------------------------------------------------------------------===//
     37 /// SelectionDAGLegalize - This takes an arbitrary SelectionDAG as input and
     38 /// hacks on it until the target machine can handle it.  This involves
     39 /// eliminating value sizes the machine cannot handle (promoting small sizes to
     40 /// large sizes or splitting up large values into small values) as well as
     41 /// eliminating operations the machine cannot handle.
     42 ///
     43 /// This code also does a small amount of optimization and recognition of idioms
     44 /// as part of its processing.  For example, if a target does not support a
     45 /// 'setcc' instruction efficiently, but does support 'brcc' instruction, this
     46 /// will attempt merge setcc and brc instructions into brcc's.
     47 ///
     48 namespace {
     49 class SelectionDAGLegalize {
     50   const TargetMachine &TM;
     51   const TargetLowering &TLI;
     52   SelectionDAG &DAG;
     53 
     54   // Libcall insertion helpers.
     55 
     56   /// LastCALLSEQ_END - This keeps track of the CALLSEQ_END node that has been
     57   /// legalized.  We use this to ensure that calls are properly serialized
     58   /// against each other, including inserted libcalls.
     59   SDValue LastCALLSEQ_END;
     60 
     61   /// IsLegalizingCall - This member is used *only* for purposes of providing
     62   /// helpful assertions that a libcall isn't created while another call is
     63   /// being legalized (which could lead to non-serialized call sequences).
     64   bool IsLegalizingCall;
     65 
     66   /// LegalizedNodes - For nodes that are of legal width, and that have more
     67   /// than one use, this map indicates what regularized operand to use.  This
     68   /// allows us to avoid legalizing the same thing more than once.
     69   DenseMap<SDValue, SDValue> LegalizedNodes;
     70 
     71   void AddLegalizedOperand(SDValue From, SDValue To) {
     72     LegalizedNodes.insert(std::make_pair(From, To));
     73     // If someone requests legalization of the new node, return itself.
     74     if (From != To)
     75       LegalizedNodes.insert(std::make_pair(To, To));
     76 
     77     // Transfer SDDbgValues.
     78     DAG.TransferDbgValues(From, To);
     79   }
     80 
     81 public:
     82   explicit SelectionDAGLegalize(SelectionDAG &DAG);
     83 
     84   void LegalizeDAG();
     85 
     86 private:
     87   /// LegalizeOp - Return a legal replacement for the given operation, with
     88   /// all legal operands.
     89   SDValue LegalizeOp(SDValue O);
     90 
     91   SDValue OptimizeFloatStore(StoreSDNode *ST);
     92 
     93   /// PerformInsertVectorEltInMemory - Some target cannot handle a variable
     94   /// insertion index for the INSERT_VECTOR_ELT instruction.  In this case, it
     95   /// is necessary to spill the vector being inserted into to memory, perform
     96   /// the insert there, and then read the result back.
     97   SDValue PerformInsertVectorEltInMemory(SDValue Vec, SDValue Val,
     98                                          SDValue Idx, DebugLoc dl);
     99   SDValue ExpandINSERT_VECTOR_ELT(SDValue Vec, SDValue Val,
    100                                   SDValue Idx, DebugLoc dl);
    101 
    102   /// ShuffleWithNarrowerEltType - Return a vector shuffle operation which
    103   /// performs the same shuffe in terms of order or result bytes, but on a type
    104   /// whose vector element type is narrower than the original shuffle type.
    105   /// e.g. <v4i32> <0, 1, 0, 1> -> v8i16 <0, 1, 2, 3, 0, 1, 2, 3>
    106   SDValue ShuffleWithNarrowerEltType(EVT NVT, EVT VT, DebugLoc dl,
    107                                      SDValue N1, SDValue N2,
    108                                      SmallVectorImpl<int> &Mask) const;
    109 
    110   bool LegalizeAllNodesNotLeadingTo(SDNode *N, SDNode *Dest,
    111                                     SmallPtrSet<SDNode*, 32> &NodesLeadingTo);
    112 
    113   void LegalizeSetCCCondCode(EVT VT, SDValue &LHS, SDValue &RHS, SDValue &CC,
    114                              DebugLoc dl);
    115 
    116   SDValue ExpandLibCall(RTLIB::Libcall LC, SDNode *Node, bool isSigned);
    117   SDValue ExpandLibCall(RTLIB::Libcall LC, EVT RetVT, const SDValue *Ops,
    118                         unsigned NumOps, bool isSigned, DebugLoc dl);
    119 
    120   std::pair<SDValue, SDValue> ExpandChainLibCall(RTLIB::Libcall LC,
    121                                                  SDNode *Node, bool isSigned);
    122   SDValue ExpandFPLibCall(SDNode *Node, RTLIB::Libcall Call_F32,
    123                           RTLIB::Libcall Call_F64, RTLIB::Libcall Call_F80,
    124                           RTLIB::Libcall Call_PPCF128);
    125   SDValue ExpandIntLibCall(SDNode *Node, bool isSigned,
    126                            RTLIB::Libcall Call_I8,
    127                            RTLIB::Libcall Call_I16,
    128                            RTLIB::Libcall Call_I32,
    129                            RTLIB::Libcall Call_I64,
    130                            RTLIB::Libcall Call_I128);
    131   void ExpandDivRemLibCall(SDNode *Node, SmallVectorImpl<SDValue> &Results);
    132 
    133   SDValue EmitStackConvert(SDValue SrcOp, EVT SlotVT, EVT DestVT, DebugLoc dl);
    134   SDValue ExpandBUILD_VECTOR(SDNode *Node);
    135   SDValue ExpandSCALAR_TO_VECTOR(SDNode *Node);
    136   void ExpandDYNAMIC_STACKALLOC(SDNode *Node,
    137                                 SmallVectorImpl<SDValue> &Results);
    138   SDValue ExpandFCOPYSIGN(SDNode *Node);
    139   SDValue ExpandLegalINT_TO_FP(bool isSigned, SDValue LegalOp, EVT DestVT,
    140                                DebugLoc dl);
    141   SDValue PromoteLegalINT_TO_FP(SDValue LegalOp, EVT DestVT, bool isSigned,
    142                                 DebugLoc dl);
    143   SDValue PromoteLegalFP_TO_INT(SDValue LegalOp, EVT DestVT, bool isSigned,
    144                                 DebugLoc dl);
    145 
    146   SDValue ExpandBSWAP(SDValue Op, DebugLoc dl);
    147   SDValue ExpandBitCount(unsigned Opc, SDValue Op, DebugLoc dl);
    148 
    149   SDValue ExpandExtractFromVectorThroughStack(SDValue Op);
    150   SDValue ExpandInsertToVectorThroughStack(SDValue Op);
    151   SDValue ExpandVectorBuildThroughStack(SDNode* Node);
    152 
    153   std::pair<SDValue, SDValue> ExpandAtomic(SDNode *Node);
    154 
    155   void ExpandNode(SDNode *Node, SmallVectorImpl<SDValue> &Results);
    156   void PromoteNode(SDNode *Node, SmallVectorImpl<SDValue> &Results);
    157 };
    158 }
    159 
    160 /// ShuffleWithNarrowerEltType - Return a vector shuffle operation which
    161 /// performs the same shuffe in terms of order or result bytes, but on a type
    162 /// whose vector element type is narrower than the original shuffle type.
    163 /// e.g. <v4i32> <0, 1, 0, 1> -> v8i16 <0, 1, 2, 3, 0, 1, 2, 3>
    164 SDValue
    165 SelectionDAGLegalize::ShuffleWithNarrowerEltType(EVT NVT, EVT VT,  DebugLoc dl,
    166                                                  SDValue N1, SDValue N2,
    167                                              SmallVectorImpl<int> &Mask) const {
    168   unsigned NumMaskElts = VT.getVectorNumElements();
    169   unsigned NumDestElts = NVT.getVectorNumElements();
    170   unsigned NumEltsGrowth = NumDestElts / NumMaskElts;
    171 
    172   assert(NumEltsGrowth && "Cannot promote to vector type with fewer elts!");
    173 
    174   if (NumEltsGrowth == 1)
    175     return DAG.getVectorShuffle(NVT, dl, N1, N2, &Mask[0]);
    176 
    177   SmallVector<int, 8> NewMask;
    178   for (unsigned i = 0; i != NumMaskElts; ++i) {
    179     int Idx = Mask[i];
    180     for (unsigned j = 0; j != NumEltsGrowth; ++j) {
    181       if (Idx < 0)
    182         NewMask.push_back(-1);
    183       else
    184         NewMask.push_back(Idx * NumEltsGrowth + j);
    185     }
    186   }
    187   assert(NewMask.size() == NumDestElts && "Non-integer NumEltsGrowth?");
    188   assert(TLI.isShuffleMaskLegal(NewMask, NVT) && "Shuffle not legal?");
    189   return DAG.getVectorShuffle(NVT, dl, N1, N2, &NewMask[0]);
    190 }
    191 
    192 SelectionDAGLegalize::SelectionDAGLegalize(SelectionDAG &dag)
    193   : TM(dag.getTarget()), TLI(dag.getTargetLoweringInfo()),
    194     DAG(dag) {
    195 }
    196 
    197 void SelectionDAGLegalize::LegalizeDAG() {
    198   LastCALLSEQ_END = DAG.getEntryNode();
    199   IsLegalizingCall = false;
    200 
    201   // The legalize process is inherently a bottom-up recursive process (users
    202   // legalize their uses before themselves).  Given infinite stack space, we
    203   // could just start legalizing on the root and traverse the whole graph.  In
    204   // practice however, this causes us to run out of stack space on large basic
    205   // blocks.  To avoid this problem, compute an ordering of the nodes where each
    206   // node is only legalized after all of its operands are legalized.
    207   DAG.AssignTopologicalOrder();
    208   for (SelectionDAG::allnodes_iterator I = DAG.allnodes_begin(),
    209        E = prior(DAG.allnodes_end()); I != llvm::next(E); ++I)
    210     LegalizeOp(SDValue(I, 0));
    211 
    212   // Finally, it's possible the root changed.  Get the new root.
    213   SDValue OldRoot = DAG.getRoot();
    214   assert(LegalizedNodes.count(OldRoot) && "Root didn't get legalized?");
    215   DAG.setRoot(LegalizedNodes[OldRoot]);
    216 
    217   LegalizedNodes.clear();
    218 
    219   // Remove dead nodes now.
    220   DAG.RemoveDeadNodes();
    221 }
    222 
    223 
    224 /// FindCallEndFromCallStart - Given a chained node that is part of a call
    225 /// sequence, find the CALLSEQ_END node that terminates the call sequence.
    226 static SDNode *FindCallEndFromCallStart(SDNode *Node, int depth = 0) {
    227   // Nested CALLSEQ_START/END constructs aren't yet legal,
    228   // but we can DTRT and handle them correctly here.
    229   if (Node->getOpcode() == ISD::CALLSEQ_START)
    230     depth++;
    231   else if (Node->getOpcode() == ISD::CALLSEQ_END) {
    232     depth--;
    233     if (depth == 0)
    234       return Node;
    235   }
    236   if (Node->use_empty())
    237     return 0;   // No CallSeqEnd
    238 
    239   // The chain is usually at the end.
    240   SDValue TheChain(Node, Node->getNumValues()-1);
    241   if (TheChain.getValueType() != MVT::Other) {
    242     // Sometimes it's at the beginning.
    243     TheChain = SDValue(Node, 0);
    244     if (TheChain.getValueType() != MVT::Other) {
    245       // Otherwise, hunt for it.
    246       for (unsigned i = 1, e = Node->getNumValues(); i != e; ++i)
    247         if (Node->getValueType(i) == MVT::Other) {
    248           TheChain = SDValue(Node, i);
    249           break;
    250         }
    251 
    252       // Otherwise, we walked into a node without a chain.
    253       if (TheChain.getValueType() != MVT::Other)
    254         return 0;
    255     }
    256   }
    257 
    258   for (SDNode::use_iterator UI = Node->use_begin(),
    259        E = Node->use_end(); UI != E; ++UI) {
    260 
    261     // Make sure to only follow users of our token chain.
    262     SDNode *User = *UI;
    263     for (unsigned i = 0, e = User->getNumOperands(); i != e; ++i)
    264       if (User->getOperand(i) == TheChain)
    265         if (SDNode *Result = FindCallEndFromCallStart(User, depth))
    266           return Result;
    267   }
    268   return 0;
    269 }
    270 
    271 /// FindCallStartFromCallEnd - Given a chained node that is part of a call
    272 /// sequence, find the CALLSEQ_START node that initiates the call sequence.
    273 static SDNode *FindCallStartFromCallEnd(SDNode *Node) {
    274   int nested = 0;
    275   assert(Node && "Didn't find callseq_start for a call??");
    276   while (Node->getOpcode() != ISD::CALLSEQ_START || nested) {
    277     Node = Node->getOperand(0).getNode();
    278     assert(Node->getOperand(0).getValueType() == MVT::Other &&
    279            "Node doesn't have a token chain argument!");
    280     switch (Node->getOpcode()) {
    281     default:
    282       break;
    283     case ISD::CALLSEQ_START:
    284       if (!nested)
    285         return Node;
    286       nested--;
    287       break;
    288     case ISD::CALLSEQ_END:
    289       nested++;
    290       break;
    291     }
    292   }
    293   return 0;
    294 }
    295 
    296 /// LegalizeAllNodesNotLeadingTo - Recursively walk the uses of N, looking to
    297 /// see if any uses can reach Dest.  If no dest operands can get to dest,
    298 /// legalize them, legalize ourself, and return false, otherwise, return true.
    299 ///
    300 /// Keep track of the nodes we fine that actually do lead to Dest in
    301 /// NodesLeadingTo.  This avoids retraversing them exponential number of times.
    302 ///
    303 bool SelectionDAGLegalize::LegalizeAllNodesNotLeadingTo(SDNode *N, SDNode *Dest,
    304                                      SmallPtrSet<SDNode*, 32> &NodesLeadingTo) {
    305   if (N == Dest) return true;  // N certainly leads to Dest :)
    306 
    307   // If we've already processed this node and it does lead to Dest, there is no
    308   // need to reprocess it.
    309   if (NodesLeadingTo.count(N)) return true;
    310 
    311   // If the first result of this node has been already legalized, then it cannot
    312   // reach N.
    313   if (LegalizedNodes.count(SDValue(N, 0))) return false;
    314 
    315   // Okay, this node has not already been legalized.  Check and legalize all
    316   // operands.  If none lead to Dest, then we can legalize this node.
    317   bool OperandsLeadToDest = false;
    318   for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
    319     OperandsLeadToDest |=     // If an operand leads to Dest, so do we.
    320       LegalizeAllNodesNotLeadingTo(N->getOperand(i).getNode(), Dest,
    321                                    NodesLeadingTo);
    322 
    323   if (OperandsLeadToDest) {
    324     NodesLeadingTo.insert(N);
    325     return true;
    326   }
    327 
    328   // Okay, this node looks safe, legalize it and return false.
    329   LegalizeOp(SDValue(N, 0));
    330   return false;
    331 }
    332 
    333 /// ExpandConstantFP - Expands the ConstantFP node to an integer constant or
    334 /// a load from the constant pool.
    335 static SDValue ExpandConstantFP(ConstantFPSDNode *CFP, bool UseCP,
    336                                 SelectionDAG &DAG, const TargetLowering &TLI) {
    337   bool Extend = false;
    338   DebugLoc dl = CFP->getDebugLoc();
    339 
    340   // If a FP immediate is precise when represented as a float and if the
    341   // target can do an extending load from float to double, we put it into
    342   // the constant pool as a float, even if it's is statically typed as a
    343   // double.  This shrinks FP constants and canonicalizes them for targets where
    344   // an FP extending load is the same cost as a normal load (such as on the x87
    345   // fp stack or PPC FP unit).
    346   EVT VT = CFP->getValueType(0);
    347   ConstantFP *LLVMC = const_cast<ConstantFP*>(CFP->getConstantFPValue());
    348   if (!UseCP) {
    349     assert((VT == MVT::f64 || VT == MVT::f32) && "Invalid type expansion");
    350     return DAG.getConstant(LLVMC->getValueAPF().bitcastToAPInt(),
    351                            (VT == MVT::f64) ? MVT::i64 : MVT::i32);
    352   }
    353 
    354   EVT OrigVT = VT;
    355   EVT SVT = VT;
    356   while (SVT != MVT::f32) {
    357     SVT = (MVT::SimpleValueType)(SVT.getSimpleVT().SimpleTy - 1);
    358     if (ConstantFPSDNode::isValueValidForType(SVT, CFP->getValueAPF()) &&
    359         // Only do this if the target has a native EXTLOAD instruction from
    360         // smaller type.
    361         TLI.isLoadExtLegal(ISD::EXTLOAD, SVT) &&
    362         TLI.ShouldShrinkFPConstant(OrigVT)) {
    363       Type *SType = SVT.getTypeForEVT(*DAG.getContext());
    364       LLVMC = cast<ConstantFP>(ConstantExpr::getFPTrunc(LLVMC, SType));
    365       VT = SVT;
    366       Extend = true;
    367     }
    368   }
    369 
    370   SDValue CPIdx = DAG.getConstantPool(LLVMC, TLI.getPointerTy());
    371   unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
    372   if (Extend)
    373     return DAG.getExtLoad(ISD::EXTLOAD, dl, OrigVT,
    374                           DAG.getEntryNode(),
    375                           CPIdx, MachinePointerInfo::getConstantPool(),
    376                           VT, false, false, Alignment);
    377   return DAG.getLoad(OrigVT, dl, DAG.getEntryNode(), CPIdx,
    378                      MachinePointerInfo::getConstantPool(), false, false,
    379                      Alignment);
    380 }
    381 
    382 /// ExpandUnalignedStore - Expands an unaligned store to 2 half-size stores.
    383 static
    384 SDValue ExpandUnalignedStore(StoreSDNode *ST, SelectionDAG &DAG,
    385                              const TargetLowering &TLI) {
    386   SDValue Chain = ST->getChain();
    387   SDValue Ptr = ST->getBasePtr();
    388   SDValue Val = ST->getValue();
    389   EVT VT = Val.getValueType();
    390   int Alignment = ST->getAlignment();
    391   DebugLoc dl = ST->getDebugLoc();
    392   if (ST->getMemoryVT().isFloatingPoint() ||
    393       ST->getMemoryVT().isVector()) {
    394     EVT intVT = EVT::getIntegerVT(*DAG.getContext(), VT.getSizeInBits());
    395     if (TLI.isTypeLegal(intVT)) {
    396       // Expand to a bitconvert of the value to the integer type of the
    397       // same size, then a (misaligned) int store.
    398       // FIXME: Does not handle truncating floating point stores!
    399       SDValue Result = DAG.getNode(ISD::BITCAST, dl, intVT, Val);
    400       return DAG.getStore(Chain, dl, Result, Ptr, ST->getPointerInfo(),
    401                           ST->isVolatile(), ST->isNonTemporal(), Alignment);
    402     }
    403     // Do a (aligned) store to a stack slot, then copy from the stack slot
    404     // to the final destination using (unaligned) integer loads and stores.
    405     EVT StoredVT = ST->getMemoryVT();
    406     EVT RegVT =
    407       TLI.getRegisterType(*DAG.getContext(),
    408                           EVT::getIntegerVT(*DAG.getContext(),
    409                                             StoredVT.getSizeInBits()));
    410     unsigned StoredBytes = StoredVT.getSizeInBits() / 8;
    411     unsigned RegBytes = RegVT.getSizeInBits() / 8;
    412     unsigned NumRegs = (StoredBytes + RegBytes - 1) / RegBytes;
    413 
    414     // Make sure the stack slot is also aligned for the register type.
    415     SDValue StackPtr = DAG.CreateStackTemporary(StoredVT, RegVT);
    416 
    417     // Perform the original store, only redirected to the stack slot.
    418     SDValue Store = DAG.getTruncStore(Chain, dl,
    419                                       Val, StackPtr, MachinePointerInfo(),
    420                                       StoredVT, false, false, 0);
    421     SDValue Increment = DAG.getConstant(RegBytes, TLI.getPointerTy());
    422     SmallVector<SDValue, 8> Stores;
    423     unsigned Offset = 0;
    424 
    425     // Do all but one copies using the full register width.
    426     for (unsigned i = 1; i < NumRegs; i++) {
    427       // Load one integer register's worth from the stack slot.
    428       SDValue Load = DAG.getLoad(RegVT, dl, Store, StackPtr,
    429                                  MachinePointerInfo(),
    430                                  false, false, 0);
    431       // Store it to the final location.  Remember the store.
    432       Stores.push_back(DAG.getStore(Load.getValue(1), dl, Load, Ptr,
    433                                   ST->getPointerInfo().getWithOffset(Offset),
    434                                     ST->isVolatile(), ST->isNonTemporal(),
    435                                     MinAlign(ST->getAlignment(), Offset)));
    436       // Increment the pointers.
    437       Offset += RegBytes;
    438       StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
    439                              Increment);
    440       Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr, Increment);
    441     }
    442 
    443     // The last store may be partial.  Do a truncating store.  On big-endian
    444     // machines this requires an extending load from the stack slot to ensure
    445     // that the bits are in the right place.
    446     EVT MemVT = EVT::getIntegerVT(*DAG.getContext(),
    447                                   8 * (StoredBytes - Offset));
    448 
    449     // Load from the stack slot.
    450     SDValue Load = DAG.getExtLoad(ISD::EXTLOAD, dl, RegVT, Store, StackPtr,
    451                                   MachinePointerInfo(),
    452                                   MemVT, false, false, 0);
    453 
    454     Stores.push_back(DAG.getTruncStore(Load.getValue(1), dl, Load, Ptr,
    455                                        ST->getPointerInfo()
    456                                          .getWithOffset(Offset),
    457                                        MemVT, ST->isVolatile(),
    458                                        ST->isNonTemporal(),
    459                                        MinAlign(ST->getAlignment(), Offset)));
    460     // The order of the stores doesn't matter - say it with a TokenFactor.
    461     return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &Stores[0],
    462                        Stores.size());
    463   }
    464   assert(ST->getMemoryVT().isInteger() &&
    465          !ST->getMemoryVT().isVector() &&
    466          "Unaligned store of unknown type.");
    467   // Get the half-size VT
    468   EVT NewStoredVT = ST->getMemoryVT().getHalfSizedIntegerVT(*DAG.getContext());
    469   int NumBits = NewStoredVT.getSizeInBits();
    470   int IncrementSize = NumBits / 8;
    471 
    472   // Divide the stored value in two parts.
    473   SDValue ShiftAmount = DAG.getConstant(NumBits,
    474                                       TLI.getShiftAmountTy(Val.getValueType()));
    475   SDValue Lo = Val;
    476   SDValue Hi = DAG.getNode(ISD::SRL, dl, VT, Val, ShiftAmount);
    477 
    478   // Store the two parts
    479   SDValue Store1, Store2;
    480   Store1 = DAG.getTruncStore(Chain, dl, TLI.isLittleEndian()?Lo:Hi, Ptr,
    481                              ST->getPointerInfo(), NewStoredVT,
    482                              ST->isVolatile(), ST->isNonTemporal(), Alignment);
    483   Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
    484                     DAG.getConstant(IncrementSize, TLI.getPointerTy()));
    485   Alignment = MinAlign(Alignment, IncrementSize);
    486   Store2 = DAG.getTruncStore(Chain, dl, TLI.isLittleEndian()?Hi:Lo, Ptr,
    487                              ST->getPointerInfo().getWithOffset(IncrementSize),
    488                              NewStoredVT, ST->isVolatile(), ST->isNonTemporal(),
    489                              Alignment);
    490 
    491   return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Store1, Store2);
    492 }
    493 
    494 /// ExpandUnalignedLoad - Expands an unaligned load to 2 half-size loads.
    495 static
    496 SDValue ExpandUnalignedLoad(LoadSDNode *LD, SelectionDAG &DAG,
    497                             const TargetLowering &TLI) {
    498   SDValue Chain = LD->getChain();
    499   SDValue Ptr = LD->getBasePtr();
    500   EVT VT = LD->getValueType(0);
    501   EVT LoadedVT = LD->getMemoryVT();
    502   DebugLoc dl = LD->getDebugLoc();
    503   if (VT.isFloatingPoint() || VT.isVector()) {
    504     EVT intVT = EVT::getIntegerVT(*DAG.getContext(), LoadedVT.getSizeInBits());
    505     if (TLI.isTypeLegal(intVT)) {
    506       // Expand to a (misaligned) integer load of the same size,
    507       // then bitconvert to floating point or vector.
    508       SDValue newLoad = DAG.getLoad(intVT, dl, Chain, Ptr, LD->getPointerInfo(),
    509                                     LD->isVolatile(),
    510                                     LD->isNonTemporal(), LD->getAlignment());
    511       SDValue Result = DAG.getNode(ISD::BITCAST, dl, LoadedVT, newLoad);
    512       if (VT.isFloatingPoint() && LoadedVT != VT)
    513         Result = DAG.getNode(ISD::FP_EXTEND, dl, VT, Result);
    514 
    515       SDValue Ops[] = { Result, Chain };
    516       return DAG.getMergeValues(Ops, 2, dl);
    517     }
    518 
    519     // Copy the value to a (aligned) stack slot using (unaligned) integer
    520     // loads and stores, then do a (aligned) load from the stack slot.
    521     EVT RegVT = TLI.getRegisterType(*DAG.getContext(), intVT);
    522     unsigned LoadedBytes = LoadedVT.getSizeInBits() / 8;
    523     unsigned RegBytes = RegVT.getSizeInBits() / 8;
    524     unsigned NumRegs = (LoadedBytes + RegBytes - 1) / RegBytes;
    525 
    526     // Make sure the stack slot is also aligned for the register type.
    527     SDValue StackBase = DAG.CreateStackTemporary(LoadedVT, RegVT);
    528 
    529     SDValue Increment = DAG.getConstant(RegBytes, TLI.getPointerTy());
    530     SmallVector<SDValue, 8> Stores;
    531     SDValue StackPtr = StackBase;
    532     unsigned Offset = 0;
    533 
    534     // Do all but one copies using the full register width.
    535     for (unsigned i = 1; i < NumRegs; i++) {
    536       // Load one integer register's worth from the original location.
    537       SDValue Load = DAG.getLoad(RegVT, dl, Chain, Ptr,
    538                                  LD->getPointerInfo().getWithOffset(Offset),
    539                                  LD->isVolatile(), LD->isNonTemporal(),
    540                                  MinAlign(LD->getAlignment(), Offset));
    541       // Follow the load with a store to the stack slot.  Remember the store.
    542       Stores.push_back(DAG.getStore(Load.getValue(1), dl, Load, StackPtr,
    543                                     MachinePointerInfo(), false, false, 0));
    544       // Increment the pointers.
    545       Offset += RegBytes;
    546       Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr, Increment);
    547       StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
    548                              Increment);
    549     }
    550 
    551     // The last copy may be partial.  Do an extending load.
    552     EVT MemVT = EVT::getIntegerVT(*DAG.getContext(),
    553                                   8 * (LoadedBytes - Offset));
    554     SDValue Load = DAG.getExtLoad(ISD::EXTLOAD, dl, RegVT, Chain, Ptr,
    555                                   LD->getPointerInfo().getWithOffset(Offset),
    556                                   MemVT, LD->isVolatile(),
    557                                   LD->isNonTemporal(),
    558                                   MinAlign(LD->getAlignment(), Offset));
    559     // Follow the load with a store to the stack slot.  Remember the store.
    560     // On big-endian machines this requires a truncating store to ensure
    561     // that the bits end up in the right place.
    562     Stores.push_back(DAG.getTruncStore(Load.getValue(1), dl, Load, StackPtr,
    563                                        MachinePointerInfo(), MemVT,
    564                                        false, false, 0));
    565 
    566     // The order of the stores doesn't matter - say it with a TokenFactor.
    567     SDValue TF = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &Stores[0],
    568                              Stores.size());
    569 
    570     // Finally, perform the original load only redirected to the stack slot.
    571     Load = DAG.getExtLoad(LD->getExtensionType(), dl, VT, TF, StackBase,
    572                           MachinePointerInfo(), LoadedVT, false, false, 0);
    573 
    574     // Callers expect a MERGE_VALUES node.
    575     SDValue Ops[] = { Load, TF };
    576     return DAG.getMergeValues(Ops, 2, dl);
    577   }
    578   assert(LoadedVT.isInteger() && !LoadedVT.isVector() &&
    579          "Unaligned load of unsupported type.");
    580 
    581   // Compute the new VT that is half the size of the old one.  This is an
    582   // integer MVT.
    583   unsigned NumBits = LoadedVT.getSizeInBits();
    584   EVT NewLoadedVT;
    585   NewLoadedVT = EVT::getIntegerVT(*DAG.getContext(), NumBits/2);
    586   NumBits >>= 1;
    587 
    588   unsigned Alignment = LD->getAlignment();
    589   unsigned IncrementSize = NumBits / 8;
    590   ISD::LoadExtType HiExtType = LD->getExtensionType();
    591 
    592   // If the original load is NON_EXTLOAD, the hi part load must be ZEXTLOAD.
    593   if (HiExtType == ISD::NON_EXTLOAD)
    594     HiExtType = ISD::ZEXTLOAD;
    595 
    596   // Load the value in two parts
    597   SDValue Lo, Hi;
    598   if (TLI.isLittleEndian()) {
    599     Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, VT, Chain, Ptr, LD->getPointerInfo(),
    600                         NewLoadedVT, LD->isVolatile(),
    601                         LD->isNonTemporal(), Alignment);
    602     Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
    603                       DAG.getConstant(IncrementSize, TLI.getPointerTy()));
    604     Hi = DAG.getExtLoad(HiExtType, dl, VT, Chain, Ptr,
    605                         LD->getPointerInfo().getWithOffset(IncrementSize),
    606                         NewLoadedVT, LD->isVolatile(),
    607                         LD->isNonTemporal(), MinAlign(Alignment,IncrementSize));
    608   } else {
    609     Hi = DAG.getExtLoad(HiExtType, dl, VT, Chain, Ptr, LD->getPointerInfo(),
    610                         NewLoadedVT, LD->isVolatile(),
    611                         LD->isNonTemporal(), Alignment);
    612     Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
    613                       DAG.getConstant(IncrementSize, TLI.getPointerTy()));
    614     Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, VT, Chain, Ptr,
    615                         LD->getPointerInfo().getWithOffset(IncrementSize),
    616                         NewLoadedVT, LD->isVolatile(),
    617                         LD->isNonTemporal(), MinAlign(Alignment,IncrementSize));
    618   }
    619 
    620   // aggregate the two parts
    621   SDValue ShiftAmount = DAG.getConstant(NumBits,
    622                                        TLI.getShiftAmountTy(Hi.getValueType()));
    623   SDValue Result = DAG.getNode(ISD::SHL, dl, VT, Hi, ShiftAmount);
    624   Result = DAG.getNode(ISD::OR, dl, VT, Result, Lo);
    625 
    626   SDValue TF = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
    627                              Hi.getValue(1));
    628 
    629   SDValue Ops[] = { Result, TF };
    630   return DAG.getMergeValues(Ops, 2, dl);
    631 }
    632 
    633 /// PerformInsertVectorEltInMemory - Some target cannot handle a variable
    634 /// insertion index for the INSERT_VECTOR_ELT instruction.  In this case, it
    635 /// is necessary to spill the vector being inserted into to memory, perform
    636 /// the insert there, and then read the result back.
    637 SDValue SelectionDAGLegalize::
    638 PerformInsertVectorEltInMemory(SDValue Vec, SDValue Val, SDValue Idx,
    639                                DebugLoc dl) {
    640   SDValue Tmp1 = Vec;
    641   SDValue Tmp2 = Val;
    642   SDValue Tmp3 = Idx;
    643 
    644   // If the target doesn't support this, we have to spill the input vector
    645   // to a temporary stack slot, update the element, then reload it.  This is
    646   // badness.  We could also load the value into a vector register (either
    647   // with a "move to register" or "extload into register" instruction, then
    648   // permute it into place, if the idx is a constant and if the idx is
    649   // supported by the target.
    650   EVT VT    = Tmp1.getValueType();
    651   EVT EltVT = VT.getVectorElementType();
    652   EVT IdxVT = Tmp3.getValueType();
    653   EVT PtrVT = TLI.getPointerTy();
    654   SDValue StackPtr = DAG.CreateStackTemporary(VT);
    655 
    656   int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
    657 
    658   // Store the vector.
    659   SDValue Ch = DAG.getStore(DAG.getEntryNode(), dl, Tmp1, StackPtr,
    660                             MachinePointerInfo::getFixedStack(SPFI),
    661                             false, false, 0);
    662 
    663   // Truncate or zero extend offset to target pointer type.
    664   unsigned CastOpc = IdxVT.bitsGT(PtrVT) ? ISD::TRUNCATE : ISD::ZERO_EXTEND;
    665   Tmp3 = DAG.getNode(CastOpc, dl, PtrVT, Tmp3);
    666   // Add the offset to the index.
    667   unsigned EltSize = EltVT.getSizeInBits()/8;
    668   Tmp3 = DAG.getNode(ISD::MUL, dl, IdxVT, Tmp3,DAG.getConstant(EltSize, IdxVT));
    669   SDValue StackPtr2 = DAG.getNode(ISD::ADD, dl, IdxVT, Tmp3, StackPtr);
    670   // Store the scalar value.
    671   Ch = DAG.getTruncStore(Ch, dl, Tmp2, StackPtr2, MachinePointerInfo(), EltVT,
    672                          false, false, 0);
    673   // Load the updated vector.
    674   return DAG.getLoad(VT, dl, Ch, StackPtr,
    675                      MachinePointerInfo::getFixedStack(SPFI), false, false, 0);
    676 }
    677 
    678 
    679 SDValue SelectionDAGLegalize::
    680 ExpandINSERT_VECTOR_ELT(SDValue Vec, SDValue Val, SDValue Idx, DebugLoc dl) {
    681   if (ConstantSDNode *InsertPos = dyn_cast<ConstantSDNode>(Idx)) {
    682     // SCALAR_TO_VECTOR requires that the type of the value being inserted
    683     // match the element type of the vector being created, except for
    684     // integers in which case the inserted value can be over width.
    685     EVT EltVT = Vec.getValueType().getVectorElementType();
    686     if (Val.getValueType() == EltVT ||
    687         (EltVT.isInteger() && Val.getValueType().bitsGE(EltVT))) {
    688       SDValue ScVec = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl,
    689                                   Vec.getValueType(), Val);
    690 
    691       unsigned NumElts = Vec.getValueType().getVectorNumElements();
    692       // We generate a shuffle of InVec and ScVec, so the shuffle mask
    693       // should be 0,1,2,3,4,5... with the appropriate element replaced with
    694       // elt 0 of the RHS.
    695       SmallVector<int, 8> ShufOps;
    696       for (unsigned i = 0; i != NumElts; ++i)
    697         ShufOps.push_back(i != InsertPos->getZExtValue() ? i : NumElts);
    698 
    699       return DAG.getVectorShuffle(Vec.getValueType(), dl, Vec, ScVec,
    700                                   &ShufOps[0]);
    701     }
    702   }
    703   return PerformInsertVectorEltInMemory(Vec, Val, Idx, dl);
    704 }
    705 
    706 SDValue SelectionDAGLegalize::OptimizeFloatStore(StoreSDNode* ST) {
    707   // Turn 'store float 1.0, Ptr' -> 'store int 0x12345678, Ptr'
    708   // FIXME: We shouldn't do this for TargetConstantFP's.
    709   // FIXME: move this to the DAG Combiner!  Note that we can't regress due
    710   // to phase ordering between legalized code and the dag combiner.  This
    711   // probably means that we need to integrate dag combiner and legalizer
    712   // together.
    713   // We generally can't do this one for long doubles.
    714   SDValue Tmp1 = ST->getChain();
    715   SDValue Tmp2 = ST->getBasePtr();
    716   SDValue Tmp3;
    717   unsigned Alignment = ST->getAlignment();
    718   bool isVolatile = ST->isVolatile();
    719   bool isNonTemporal = ST->isNonTemporal();
    720   DebugLoc dl = ST->getDebugLoc();
    721   if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(ST->getValue())) {
    722     if (CFP->getValueType(0) == MVT::f32 &&
    723         TLI.isTypeLegal(MVT::i32)) {
    724       Tmp3 = DAG.getConstant(CFP->getValueAPF().
    725                                       bitcastToAPInt().zextOrTrunc(32),
    726                               MVT::i32);
    727       return DAG.getStore(Tmp1, dl, Tmp3, Tmp2, ST->getPointerInfo(),
    728                           isVolatile, isNonTemporal, Alignment);
    729     }
    730 
    731     if (CFP->getValueType(0) == MVT::f64) {
    732       // If this target supports 64-bit registers, do a single 64-bit store.
    733       if (TLI.isTypeLegal(MVT::i64)) {
    734         Tmp3 = DAG.getConstant(CFP->getValueAPF().bitcastToAPInt().
    735                                   zextOrTrunc(64), MVT::i64);
    736         return DAG.getStore(Tmp1, dl, Tmp3, Tmp2, ST->getPointerInfo(),
    737                             isVolatile, isNonTemporal, Alignment);
    738       }
    739 
    740       if (TLI.isTypeLegal(MVT::i32) && !ST->isVolatile()) {
    741         // Otherwise, if the target supports 32-bit registers, use 2 32-bit
    742         // stores.  If the target supports neither 32- nor 64-bits, this
    743         // xform is certainly not worth it.
    744         const APInt &IntVal =CFP->getValueAPF().bitcastToAPInt();
    745         SDValue Lo = DAG.getConstant(IntVal.trunc(32), MVT::i32);
    746         SDValue Hi = DAG.getConstant(IntVal.lshr(32).trunc(32), MVT::i32);
    747         if (TLI.isBigEndian()) std::swap(Lo, Hi);
    748 
    749         Lo = DAG.getStore(Tmp1, dl, Lo, Tmp2, ST->getPointerInfo(), isVolatile,
    750                           isNonTemporal, Alignment);
    751         Tmp2 = DAG.getNode(ISD::ADD, dl, Tmp2.getValueType(), Tmp2,
    752                             DAG.getIntPtrConstant(4));
    753         Hi = DAG.getStore(Tmp1, dl, Hi, Tmp2,
    754                           ST->getPointerInfo().getWithOffset(4),
    755                           isVolatile, isNonTemporal, MinAlign(Alignment, 4U));
    756 
    757         return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
    758       }
    759     }
    760   }
    761   return SDValue(0, 0);
    762 }
    763 
    764 /// LegalizeOp - Return a legal replacement for the given operation, with
    765 /// all legal operands.
    766 SDValue SelectionDAGLegalize::LegalizeOp(SDValue Op) {
    767   if (Op.getOpcode() == ISD::TargetConstant) // Allow illegal target nodes.
    768     return Op;
    769 
    770   SDNode *Node = Op.getNode();
    771   DebugLoc dl = Node->getDebugLoc();
    772 
    773   for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
    774     assert(TLI.getTypeAction(*DAG.getContext(), Node->getValueType(i)) ==
    775              TargetLowering::TypeLegal &&
    776            "Unexpected illegal type!");
    777 
    778   for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i)
    779     assert((TLI.getTypeAction(*DAG.getContext(),
    780                               Node->getOperand(i).getValueType()) ==
    781               TargetLowering::TypeLegal ||
    782             Node->getOperand(i).getOpcode() == ISD::TargetConstant) &&
    783            "Unexpected illegal type!");
    784 
    785   // Note that LegalizeOp may be reentered even from single-use nodes, which
    786   // means that we always must cache transformed nodes.
    787   DenseMap<SDValue, SDValue>::iterator I = LegalizedNodes.find(Op);
    788   if (I != LegalizedNodes.end()) return I->second;
    789 
    790   SDValue Tmp1, Tmp2, Tmp3, Tmp4;
    791   SDValue Result = Op;
    792   bool isCustom = false;
    793 
    794   // Figure out the correct action; the way to query this varies by opcode
    795   TargetLowering::LegalizeAction Action = TargetLowering::Legal;
    796   bool SimpleFinishLegalizing = true;
    797   switch (Node->getOpcode()) {
    798   case ISD::INTRINSIC_W_CHAIN:
    799   case ISD::INTRINSIC_WO_CHAIN:
    800   case ISD::INTRINSIC_VOID:
    801   case ISD::VAARG:
    802   case ISD::STACKSAVE:
    803     Action = TLI.getOperationAction(Node->getOpcode(), MVT::Other);
    804     break;
    805   case ISD::SINT_TO_FP:
    806   case ISD::UINT_TO_FP:
    807   case ISD::EXTRACT_VECTOR_ELT:
    808     Action = TLI.getOperationAction(Node->getOpcode(),
    809                                     Node->getOperand(0).getValueType());
    810     break;
    811   case ISD::FP_ROUND_INREG:
    812   case ISD::SIGN_EXTEND_INREG: {
    813     EVT InnerType = cast<VTSDNode>(Node->getOperand(1))->getVT();
    814     Action = TLI.getOperationAction(Node->getOpcode(), InnerType);
    815     break;
    816   }
    817   case ISD::ATOMIC_STORE: {
    818     Action = TLI.getOperationAction(Node->getOpcode(),
    819                                     Node->getOperand(2).getValueType());
    820     break;
    821   }
    822   case ISD::SELECT_CC:
    823   case ISD::SETCC:
    824   case ISD::BR_CC: {
    825     unsigned CCOperand = Node->getOpcode() == ISD::SELECT_CC ? 4 :
    826                          Node->getOpcode() == ISD::SETCC ? 2 : 1;
    827     unsigned CompareOperand = Node->getOpcode() == ISD::BR_CC ? 2 : 0;
    828     EVT OpVT = Node->getOperand(CompareOperand).getValueType();
    829     ISD::CondCode CCCode =
    830         cast<CondCodeSDNode>(Node->getOperand(CCOperand))->get();
    831     Action = TLI.getCondCodeAction(CCCode, OpVT);
    832     if (Action == TargetLowering::Legal) {
    833       if (Node->getOpcode() == ISD::SELECT_CC)
    834         Action = TLI.getOperationAction(Node->getOpcode(),
    835                                         Node->getValueType(0));
    836       else
    837         Action = TLI.getOperationAction(Node->getOpcode(), OpVT);
    838     }
    839     break;
    840   }
    841   case ISD::LOAD:
    842   case ISD::STORE:
    843     // FIXME: Model these properly.  LOAD and STORE are complicated, and
    844     // STORE expects the unlegalized operand in some cases.
    845     SimpleFinishLegalizing = false;
    846     break;
    847   case ISD::CALLSEQ_START:
    848   case ISD::CALLSEQ_END:
    849     // FIXME: This shouldn't be necessary.  These nodes have special properties
    850     // dealing with the recursive nature of legalization.  Removing this
    851     // special case should be done as part of making LegalizeDAG non-recursive.
    852     SimpleFinishLegalizing = false;
    853     break;
    854   case ISD::EXTRACT_ELEMENT:
    855   case ISD::FLT_ROUNDS_:
    856   case ISD::SADDO:
    857   case ISD::SSUBO:
    858   case ISD::UADDO:
    859   case ISD::USUBO:
    860   case ISD::SMULO:
    861   case ISD::UMULO:
    862   case ISD::FPOWI:
    863   case ISD::MERGE_VALUES:
    864   case ISD::EH_RETURN:
    865   case ISD::FRAME_TO_ARGS_OFFSET:
    866   case ISD::EH_SJLJ_SETJMP:
    867   case ISD::EH_SJLJ_LONGJMP:
    868   case ISD::EH_SJLJ_DISPATCHSETUP:
    869     // These operations lie about being legal: when they claim to be legal,
    870     // they should actually be expanded.
    871     Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
    872     if (Action == TargetLowering::Legal)
    873       Action = TargetLowering::Expand;
    874     break;
    875   case ISD::INIT_TRAMPOLINE:
    876   case ISD::ADJUST_TRAMPOLINE:
    877   case ISD::FRAMEADDR:
    878   case ISD::RETURNADDR:
    879     // These operations lie about being legal: when they claim to be legal,
    880     // they should actually be custom-lowered.
    881     Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
    882     if (Action == TargetLowering::Legal)
    883       Action = TargetLowering::Custom;
    884     break;
    885   case ISD::BUILD_VECTOR:
    886     // A weird case: legalization for BUILD_VECTOR never legalizes the
    887     // operands!
    888     // FIXME: This really sucks... changing it isn't semantically incorrect,
    889     // but it massively pessimizes the code for floating-point BUILD_VECTORs
    890     // because ConstantFP operands get legalized into constant pool loads
    891     // before the BUILD_VECTOR code can see them.  It doesn't usually bite,
    892     // though, because BUILD_VECTORS usually get lowered into other nodes
    893     // which get legalized properly.
    894     SimpleFinishLegalizing = false;
    895     break;
    896   default:
    897     if (Node->getOpcode() >= ISD::BUILTIN_OP_END) {
    898       Action = TargetLowering::Legal;
    899     } else {
    900       Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
    901     }
    902     break;
    903   }
    904 
    905   if (SimpleFinishLegalizing) {
    906     SmallVector<SDValue, 8> Ops, ResultVals;
    907     for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i)
    908       Ops.push_back(LegalizeOp(Node->getOperand(i)));
    909     switch (Node->getOpcode()) {
    910     default: break;
    911     case ISD::BR:
    912     case ISD::BRIND:
    913     case ISD::BR_JT:
    914     case ISD::BR_CC:
    915     case ISD::BRCOND:
    916       // Branches tweak the chain to include LastCALLSEQ_END
    917       Ops[0] = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Ops[0],
    918                            LastCALLSEQ_END);
    919       Ops[0] = LegalizeOp(Ops[0]);
    920       LastCALLSEQ_END = DAG.getEntryNode();
    921       break;
    922     case ISD::SHL:
    923     case ISD::SRL:
    924     case ISD::SRA:
    925     case ISD::ROTL:
    926     case ISD::ROTR:
    927       // Legalizing shifts/rotates requires adjusting the shift amount
    928       // to the appropriate width.
    929       if (!Ops[1].getValueType().isVector())
    930         Ops[1] = LegalizeOp(DAG.getShiftAmountOperand(Ops[0].getValueType(),
    931                                                       Ops[1]));
    932       break;
    933     case ISD::SRL_PARTS:
    934     case ISD::SRA_PARTS:
    935     case ISD::SHL_PARTS:
    936       // Legalizing shifts/rotates requires adjusting the shift amount
    937       // to the appropriate width.
    938       if (!Ops[2].getValueType().isVector())
    939         Ops[2] = LegalizeOp(DAG.getShiftAmountOperand(Ops[0].getValueType(),
    940                                                       Ops[2]));
    941       break;
    942     }
    943 
    944     Result = SDValue(DAG.UpdateNodeOperands(Result.getNode(), Ops.data(),
    945                                             Ops.size()), 0);
    946     switch (Action) {
    947     case TargetLowering::Legal:
    948       for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
    949         ResultVals.push_back(Result.getValue(i));
    950       break;
    951     case TargetLowering::Custom:
    952       // FIXME: The handling for custom lowering with multiple results is
    953       // a complete mess.
    954       Tmp1 = TLI.LowerOperation(Result, DAG);
    955       if (Tmp1.getNode()) {
    956         for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i) {
    957           if (e == 1)
    958             ResultVals.push_back(Tmp1);
    959           else
    960             ResultVals.push_back(Tmp1.getValue(i));
    961         }
    962         break;
    963       }
    964 
    965       // FALL THROUGH
    966     case TargetLowering::Expand:
    967       ExpandNode(Result.getNode(), ResultVals);
    968       break;
    969     case TargetLowering::Promote:
    970       PromoteNode(Result.getNode(), ResultVals);
    971       break;
    972     }
    973     if (!ResultVals.empty()) {
    974       for (unsigned i = 0, e = ResultVals.size(); i != e; ++i) {
    975         if (ResultVals[i] != SDValue(Node, i))
    976           ResultVals[i] = LegalizeOp(ResultVals[i]);
    977         AddLegalizedOperand(SDValue(Node, i), ResultVals[i]);
    978       }
    979       return ResultVals[Op.getResNo()];
    980     }
    981   }
    982 
    983   switch (Node->getOpcode()) {
    984   default:
    985 #ifndef NDEBUG
    986     dbgs() << "NODE: ";
    987     Node->dump( &DAG);
    988     dbgs() << "\n";
    989 #endif
    990     assert(0 && "Do not know how to legalize this operator!");
    991 
    992   case ISD::SRA:
    993   case ISD::SRL:
    994   case ISD::SHL: {
    995     // Scalarize vector SRA/SRL/SHL.
    996     EVT VT = Node->getValueType(0);
    997     assert(VT.isVector() && "Unable to legalize non-vector shift");
    998     assert(TLI.isTypeLegal(VT.getScalarType())&& "Element type must be legal");
    999     unsigned NumElem = VT.getVectorNumElements();
   1000 
   1001     SmallVector<SDValue, 8> Scalars;
   1002     for (unsigned Idx = 0; Idx < NumElem; Idx++) {
   1003       SDValue Ex = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl,
   1004                                VT.getScalarType(),
   1005                                Node->getOperand(0), DAG.getIntPtrConstant(Idx));
   1006       SDValue Sh = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl,
   1007                                VT.getScalarType(),
   1008                                Node->getOperand(1), DAG.getIntPtrConstant(Idx));
   1009       Scalars.push_back(DAG.getNode(Node->getOpcode(), dl,
   1010                                     VT.getScalarType(), Ex, Sh));
   1011     }
   1012     Result = DAG.getNode(ISD::BUILD_VECTOR, dl, Node->getValueType(0),
   1013                          &Scalars[0], Scalars.size());
   1014     break;
   1015   }
   1016 
   1017   case ISD::BUILD_VECTOR:
   1018     switch (TLI.getOperationAction(ISD::BUILD_VECTOR, Node->getValueType(0))) {
   1019     default: assert(0 && "This action is not supported yet!");
   1020     case TargetLowering::Custom:
   1021       Tmp3 = TLI.LowerOperation(Result, DAG);
   1022       if (Tmp3.getNode()) {
   1023         Result = Tmp3;
   1024         break;
   1025       }
   1026       // FALLTHROUGH
   1027     case TargetLowering::Expand:
   1028       Result = ExpandBUILD_VECTOR(Result.getNode());
   1029       break;
   1030     }
   1031     break;
   1032   case ISD::CALLSEQ_START: {
   1033     SDNode *CallEnd = FindCallEndFromCallStart(Node);
   1034 
   1035     // Recursively Legalize all of the inputs of the call end that do not lead
   1036     // to this call start.  This ensures that any libcalls that need be inserted
   1037     // are inserted *before* the CALLSEQ_START.
   1038     {SmallPtrSet<SDNode*, 32> NodesLeadingTo;
   1039     for (unsigned i = 0, e = CallEnd->getNumOperands(); i != e; ++i)
   1040       LegalizeAllNodesNotLeadingTo(CallEnd->getOperand(i).getNode(), Node,
   1041                                    NodesLeadingTo);
   1042     }
   1043 
   1044     // Now that we have legalized all of the inputs (which may have inserted
   1045     // libcalls), create the new CALLSEQ_START node.
   1046     Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
   1047 
   1048     // Merge in the last call to ensure that this call starts after the last
   1049     // call ended.
   1050     if (LastCALLSEQ_END.getOpcode() != ISD::EntryToken) {
   1051       Tmp1 = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
   1052                          Tmp1, LastCALLSEQ_END);
   1053       Tmp1 = LegalizeOp(Tmp1);
   1054     }
   1055 
   1056     // Do not try to legalize the target-specific arguments (#1+).
   1057     if (Tmp1 != Node->getOperand(0)) {
   1058       SmallVector<SDValue, 8> Ops(Node->op_begin(), Node->op_end());
   1059       Ops[0] = Tmp1;
   1060       Result = SDValue(DAG.UpdateNodeOperands(Result.getNode(), &Ops[0],
   1061                                               Ops.size()), Result.getResNo());
   1062     }
   1063 
   1064     // Remember that the CALLSEQ_START is legalized.
   1065     AddLegalizedOperand(Op.getValue(0), Result);
   1066     if (Node->getNumValues() == 2)    // If this has a flag result, remember it.
   1067       AddLegalizedOperand(Op.getValue(1), Result.getValue(1));
   1068 
   1069     // Now that the callseq_start and all of the non-call nodes above this call
   1070     // sequence have been legalized, legalize the call itself.  During this
   1071     // process, no libcalls can/will be inserted, guaranteeing that no calls
   1072     // can overlap.
   1073     assert(!IsLegalizingCall && "Inconsistent sequentialization of calls!");
   1074     // Note that we are selecting this call!
   1075     LastCALLSEQ_END = SDValue(CallEnd, 0);
   1076     IsLegalizingCall = true;
   1077 
   1078     // Legalize the call, starting from the CALLSEQ_END.
   1079     LegalizeOp(LastCALLSEQ_END);
   1080     assert(!IsLegalizingCall && "CALLSEQ_END should have cleared this!");
   1081     return Result;
   1082   }
   1083   case ISD::CALLSEQ_END:
   1084     // If the CALLSEQ_START node hasn't been legalized first, legalize it.  This
   1085     // will cause this node to be legalized as well as handling libcalls right.
   1086     if (LastCALLSEQ_END.getNode() != Node) {
   1087       LegalizeOp(SDValue(FindCallStartFromCallEnd(Node), 0));
   1088       DenseMap<SDValue, SDValue>::iterator I = LegalizedNodes.find(Op);
   1089       assert(I != LegalizedNodes.end() &&
   1090              "Legalizing the call start should have legalized this node!");
   1091       return I->second;
   1092     }
   1093 
   1094     // Otherwise, the call start has been legalized and everything is going
   1095     // according to plan.  Just legalize ourselves normally here.
   1096     Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
   1097     // Do not try to legalize the target-specific arguments (#1+), except for
   1098     // an optional flag input.
   1099     if (Node->getOperand(Node->getNumOperands()-1).getValueType() != MVT::Glue){
   1100       if (Tmp1 != Node->getOperand(0)) {
   1101         SmallVector<SDValue, 8> Ops(Node->op_begin(), Node->op_end());
   1102         Ops[0] = Tmp1;
   1103         Result = SDValue(DAG.UpdateNodeOperands(Result.getNode(),
   1104                                                 &Ops[0], Ops.size()),
   1105                          Result.getResNo());
   1106       }
   1107     } else {
   1108       Tmp2 = LegalizeOp(Node->getOperand(Node->getNumOperands()-1));
   1109       if (Tmp1 != Node->getOperand(0) ||
   1110           Tmp2 != Node->getOperand(Node->getNumOperands()-1)) {
   1111         SmallVector<SDValue, 8> Ops(Node->op_begin(), Node->op_end());
   1112         Ops[0] = Tmp1;
   1113         Ops.back() = Tmp2;
   1114         Result = SDValue(DAG.UpdateNodeOperands(Result.getNode(),
   1115                                                 &Ops[0], Ops.size()),
   1116                          Result.getResNo());
   1117       }
   1118     }
   1119     assert(IsLegalizingCall && "Call sequence imbalance between start/end?");
   1120     // This finishes up call legalization.
   1121     IsLegalizingCall = false;
   1122 
   1123     // If the CALLSEQ_END node has a flag, remember that we legalized it.
   1124     AddLegalizedOperand(SDValue(Node, 0), Result.getValue(0));
   1125     if (Node->getNumValues() == 2)
   1126       AddLegalizedOperand(SDValue(Node, 1), Result.getValue(1));
   1127     return Result.getValue(Op.getResNo());
   1128   case ISD::LOAD: {
   1129     LoadSDNode *LD = cast<LoadSDNode>(Node);
   1130     Tmp1 = LegalizeOp(LD->getChain());   // Legalize the chain.
   1131     Tmp2 = LegalizeOp(LD->getBasePtr()); // Legalize the base pointer.
   1132 
   1133     ISD::LoadExtType ExtType = LD->getExtensionType();
   1134     if (ExtType == ISD::NON_EXTLOAD) {
   1135       EVT VT = Node->getValueType(0);
   1136       Result = SDValue(DAG.UpdateNodeOperands(Result.getNode(),
   1137                                               Tmp1, Tmp2, LD->getOffset()),
   1138                        Result.getResNo());
   1139       Tmp3 = Result.getValue(0);
   1140       Tmp4 = Result.getValue(1);
   1141 
   1142       switch (TLI.getOperationAction(Node->getOpcode(), VT)) {
   1143       default: assert(0 && "This action is not supported yet!");
   1144       case TargetLowering::Legal:
   1145         // If this is an unaligned load and the target doesn't support it,
   1146         // expand it.
   1147         if (!TLI.allowsUnalignedMemoryAccesses(LD->getMemoryVT())) {
   1148           Type *Ty = LD->getMemoryVT().getTypeForEVT(*DAG.getContext());
   1149           unsigned ABIAlignment = TLI.getTargetData()->getABITypeAlignment(Ty);
   1150           if (LD->getAlignment() < ABIAlignment){
   1151             Result = ExpandUnalignedLoad(cast<LoadSDNode>(Result.getNode()),
   1152                                          DAG, TLI);
   1153             Tmp3 = Result.getOperand(0);
   1154             Tmp4 = Result.getOperand(1);
   1155             Tmp3 = LegalizeOp(Tmp3);
   1156             Tmp4 = LegalizeOp(Tmp4);
   1157           }
   1158         }
   1159         break;
   1160       case TargetLowering::Custom:
   1161         Tmp1 = TLI.LowerOperation(Tmp3, DAG);
   1162         if (Tmp1.getNode()) {
   1163           Tmp3 = LegalizeOp(Tmp1);
   1164           Tmp4 = LegalizeOp(Tmp1.getValue(1));
   1165         }
   1166         break;
   1167       case TargetLowering::Promote: {
   1168         // Only promote a load of vector type to another.
   1169         assert(VT.isVector() && "Cannot promote this load!");
   1170         // Change base type to a different vector type.
   1171         EVT NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), VT);
   1172 
   1173         Tmp1 = DAG.getLoad(NVT, dl, Tmp1, Tmp2, LD->getPointerInfo(),
   1174                            LD->isVolatile(), LD->isNonTemporal(),
   1175                            LD->getAlignment());
   1176         Tmp3 = LegalizeOp(DAG.getNode(ISD::BITCAST, dl, VT, Tmp1));
   1177         Tmp4 = LegalizeOp(Tmp1.getValue(1));
   1178         break;
   1179       }
   1180       }
   1181       // Since loads produce two values, make sure to remember that we
   1182       // legalized both of them.
   1183       AddLegalizedOperand(SDValue(Node, 0), Tmp3);
   1184       AddLegalizedOperand(SDValue(Node, 1), Tmp4);
   1185       return Op.getResNo() ? Tmp4 : Tmp3;
   1186     }
   1187 
   1188     EVT SrcVT = LD->getMemoryVT();
   1189     unsigned SrcWidth = SrcVT.getSizeInBits();
   1190     unsigned Alignment = LD->getAlignment();
   1191     bool isVolatile = LD->isVolatile();
   1192     bool isNonTemporal = LD->isNonTemporal();
   1193 
   1194     if (SrcWidth != SrcVT.getStoreSizeInBits() &&
   1195         // Some targets pretend to have an i1 loading operation, and actually
   1196         // load an i8.  This trick is correct for ZEXTLOAD because the top 7
   1197         // bits are guaranteed to be zero; it helps the optimizers understand
   1198         // that these bits are zero.  It is also useful for EXTLOAD, since it
   1199         // tells the optimizers that those bits are undefined.  It would be
   1200         // nice to have an effective generic way of getting these benefits...
   1201         // Until such a way is found, don't insist on promoting i1 here.
   1202         (SrcVT != MVT::i1 ||
   1203          TLI.getLoadExtAction(ExtType, MVT::i1) == TargetLowering::Promote)) {
   1204       // Promote to a byte-sized load if not loading an integral number of
   1205       // bytes.  For example, promote EXTLOAD:i20 -> EXTLOAD:i24.
   1206       unsigned NewWidth = SrcVT.getStoreSizeInBits();
   1207       EVT NVT = EVT::getIntegerVT(*DAG.getContext(), NewWidth);
   1208       SDValue Ch;
   1209 
   1210       // The extra bits are guaranteed to be zero, since we stored them that
   1211       // way.  A zext load from NVT thus automatically gives zext from SrcVT.
   1212 
   1213       ISD::LoadExtType NewExtType =
   1214         ExtType == ISD::ZEXTLOAD ? ISD::ZEXTLOAD : ISD::EXTLOAD;
   1215 
   1216       Result = DAG.getExtLoad(NewExtType, dl, Node->getValueType(0),
   1217                               Tmp1, Tmp2, LD->getPointerInfo(),
   1218                               NVT, isVolatile, isNonTemporal, Alignment);
   1219 
   1220       Ch = Result.getValue(1); // The chain.
   1221 
   1222       if (ExtType == ISD::SEXTLOAD)
   1223         // Having the top bits zero doesn't help when sign extending.
   1224         Result = DAG.getNode(ISD::SIGN_EXTEND_INREG, dl,
   1225                              Result.getValueType(),
   1226                              Result, DAG.getValueType(SrcVT));
   1227       else if (ExtType == ISD::ZEXTLOAD || NVT == Result.getValueType())
   1228         // All the top bits are guaranteed to be zero - inform the optimizers.
   1229         Result = DAG.getNode(ISD::AssertZext, dl,
   1230                              Result.getValueType(), Result,
   1231                              DAG.getValueType(SrcVT));
   1232 
   1233       Tmp1 = LegalizeOp(Result);
   1234       Tmp2 = LegalizeOp(Ch);
   1235     } else if (SrcWidth & (SrcWidth - 1)) {
   1236       // If not loading a power-of-2 number of bits, expand as two loads.
   1237       assert(!SrcVT.isVector() && "Unsupported extload!");
   1238       unsigned RoundWidth = 1 << Log2_32(SrcWidth);
   1239       assert(RoundWidth < SrcWidth);
   1240       unsigned ExtraWidth = SrcWidth - RoundWidth;
   1241       assert(ExtraWidth < RoundWidth);
   1242       assert(!(RoundWidth % 8) && !(ExtraWidth % 8) &&
   1243              "Load size not an integral number of bytes!");
   1244       EVT RoundVT = EVT::getIntegerVT(*DAG.getContext(), RoundWidth);
   1245       EVT ExtraVT = EVT::getIntegerVT(*DAG.getContext(), ExtraWidth);
   1246       SDValue Lo, Hi, Ch;
   1247       unsigned IncrementSize;
   1248 
   1249       if (TLI.isLittleEndian()) {
   1250         // EXTLOAD:i24 -> ZEXTLOAD:i16 | (shl EXTLOAD@+2:i8, 16)
   1251         // Load the bottom RoundWidth bits.
   1252         Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, Node->getValueType(0),
   1253                             Tmp1, Tmp2,
   1254                             LD->getPointerInfo(), RoundVT, isVolatile,
   1255                             isNonTemporal, Alignment);
   1256 
   1257         // Load the remaining ExtraWidth bits.
   1258         IncrementSize = RoundWidth / 8;
   1259         Tmp2 = DAG.getNode(ISD::ADD, dl, Tmp2.getValueType(), Tmp2,
   1260                            DAG.getIntPtrConstant(IncrementSize));
   1261         Hi = DAG.getExtLoad(ExtType, dl, Node->getValueType(0), Tmp1, Tmp2,
   1262                             LD->getPointerInfo().getWithOffset(IncrementSize),
   1263                             ExtraVT, isVolatile, isNonTemporal,
   1264                             MinAlign(Alignment, IncrementSize));
   1265 
   1266         // Build a factor node to remember that this load is independent of
   1267         // the other one.
   1268         Ch = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
   1269                          Hi.getValue(1));
   1270 
   1271         // Move the top bits to the right place.
   1272         Hi = DAG.getNode(ISD::SHL, dl, Hi.getValueType(), Hi,
   1273                          DAG.getConstant(RoundWidth,
   1274                                       TLI.getShiftAmountTy(Hi.getValueType())));
   1275 
   1276         // Join the hi and lo parts.
   1277         Result = DAG.getNode(ISD::OR, dl, Node->getValueType(0), Lo, Hi);
   1278       } else {
   1279         // Big endian - avoid unaligned loads.
   1280         // EXTLOAD:i24 -> (shl EXTLOAD:i16, 8) | ZEXTLOAD@+2:i8
   1281         // Load the top RoundWidth bits.
   1282         Hi = DAG.getExtLoad(ExtType, dl, Node->getValueType(0), Tmp1, Tmp2,
   1283                             LD->getPointerInfo(), RoundVT, isVolatile,
   1284                             isNonTemporal, Alignment);
   1285 
   1286         // Load the remaining ExtraWidth bits.
   1287         IncrementSize = RoundWidth / 8;
   1288         Tmp2 = DAG.getNode(ISD::ADD, dl, Tmp2.getValueType(), Tmp2,
   1289                            DAG.getIntPtrConstant(IncrementSize));
   1290         Lo = DAG.getExtLoad(ISD::ZEXTLOAD,
   1291                             dl, Node->getValueType(0), Tmp1, Tmp2,
   1292                             LD->getPointerInfo().getWithOffset(IncrementSize),
   1293                             ExtraVT, isVolatile, isNonTemporal,
   1294                             MinAlign(Alignment, IncrementSize));
   1295 
   1296         // Build a factor node to remember that this load is independent of
   1297         // the other one.
   1298         Ch = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
   1299                          Hi.getValue(1));
   1300 
   1301         // Move the top bits to the right place.
   1302         Hi = DAG.getNode(ISD::SHL, dl, Hi.getValueType(), Hi,
   1303                          DAG.getConstant(ExtraWidth,
   1304                                       TLI.getShiftAmountTy(Hi.getValueType())));
   1305 
   1306         // Join the hi and lo parts.
   1307         Result = DAG.getNode(ISD::OR, dl, Node->getValueType(0), Lo, Hi);
   1308       }
   1309 
   1310       Tmp1 = LegalizeOp(Result);
   1311       Tmp2 = LegalizeOp(Ch);
   1312     } else {
   1313       switch (TLI.getLoadExtAction(ExtType, SrcVT)) {
   1314       default: assert(0 && "This action is not supported yet!");
   1315       case TargetLowering::Custom:
   1316         isCustom = true;
   1317         // FALLTHROUGH
   1318       case TargetLowering::Legal:
   1319         Result = SDValue(DAG.UpdateNodeOperands(Result.getNode(),
   1320                                                 Tmp1, Tmp2, LD->getOffset()),
   1321                          Result.getResNo());
   1322         Tmp1 = Result.getValue(0);
   1323         Tmp2 = Result.getValue(1);
   1324 
   1325         if (isCustom) {
   1326           Tmp3 = TLI.LowerOperation(Result, DAG);
   1327           if (Tmp3.getNode()) {
   1328             Tmp1 = LegalizeOp(Tmp3);
   1329             Tmp2 = LegalizeOp(Tmp3.getValue(1));
   1330           }
   1331         } else {
   1332           // If this is an unaligned load and the target doesn't support it,
   1333           // expand it.
   1334           if (!TLI.allowsUnalignedMemoryAccesses(LD->getMemoryVT())) {
   1335             Type *Ty =
   1336               LD->getMemoryVT().getTypeForEVT(*DAG.getContext());
   1337             unsigned ABIAlignment =
   1338               TLI.getTargetData()->getABITypeAlignment(Ty);
   1339             if (LD->getAlignment() < ABIAlignment){
   1340               Result = ExpandUnalignedLoad(cast<LoadSDNode>(Result.getNode()),
   1341                                            DAG, TLI);
   1342               Tmp1 = Result.getOperand(0);
   1343               Tmp2 = Result.getOperand(1);
   1344               Tmp1 = LegalizeOp(Tmp1);
   1345               Tmp2 = LegalizeOp(Tmp2);
   1346             }
   1347           }
   1348         }
   1349         break;
   1350       case TargetLowering::Expand:
   1351         if (!TLI.isLoadExtLegal(ISD::EXTLOAD, SrcVT) && TLI.isTypeLegal(SrcVT)) {
   1352           SDValue Load = DAG.getLoad(SrcVT, dl, Tmp1, Tmp2,
   1353                                      LD->getPointerInfo(),
   1354                                      LD->isVolatile(), LD->isNonTemporal(),
   1355                                      LD->getAlignment());
   1356           unsigned ExtendOp;
   1357           switch (ExtType) {
   1358           case ISD::EXTLOAD:
   1359             ExtendOp = (SrcVT.isFloatingPoint() ?
   1360                         ISD::FP_EXTEND : ISD::ANY_EXTEND);
   1361             break;
   1362           case ISD::SEXTLOAD: ExtendOp = ISD::SIGN_EXTEND; break;
   1363           case ISD::ZEXTLOAD: ExtendOp = ISD::ZERO_EXTEND; break;
   1364           default: llvm_unreachable("Unexpected extend load type!");
   1365           }
   1366           Result = DAG.getNode(ExtendOp, dl, Node->getValueType(0), Load);
   1367           Tmp1 = LegalizeOp(Result);  // Relegalize new nodes.
   1368           Tmp2 = LegalizeOp(Load.getValue(1));
   1369           break;
   1370         }
   1371 
   1372         // If this is a promoted vector load, and the vector element types are
   1373         // legal, then scalarize it.
   1374         if (ExtType == ISD::EXTLOAD && SrcVT.isVector() &&
   1375           TLI.isTypeLegal(Node->getValueType(0).getScalarType())) {
   1376           SmallVector<SDValue, 8> LoadVals;
   1377           SmallVector<SDValue, 8> LoadChains;
   1378           unsigned NumElem = SrcVT.getVectorNumElements();
   1379           unsigned Stride = SrcVT.getScalarType().getSizeInBits()/8;
   1380 
   1381           for (unsigned Idx=0; Idx<NumElem; Idx++) {
   1382             Tmp2 = DAG.getNode(ISD::ADD, dl, Tmp2.getValueType(), Tmp2,
   1383                                 DAG.getIntPtrConstant(Stride));
   1384             SDValue ScalarLoad = DAG.getExtLoad(ISD::EXTLOAD, dl,
   1385                   Node->getValueType(0).getScalarType(),
   1386                   Tmp1, Tmp2, LD->getPointerInfo().getWithOffset(Idx * Stride),
   1387                   SrcVT.getScalarType(),
   1388                   LD->isVolatile(), LD->isNonTemporal(),
   1389                   LD->getAlignment());
   1390 
   1391             LoadVals.push_back(ScalarLoad.getValue(0));
   1392             LoadChains.push_back(ScalarLoad.getValue(1));
   1393           }
   1394           Result = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
   1395             &LoadChains[0], LoadChains.size());
   1396           SDValue ValRes = DAG.getNode(ISD::BUILD_VECTOR, dl,
   1397             Node->getValueType(0), &LoadVals[0], LoadVals.size());
   1398 
   1399           Tmp1 = LegalizeOp(ValRes);  // Relegalize new nodes.
   1400           Tmp2 = LegalizeOp(Result.getValue(0));  // Relegalize new nodes.
   1401           break;
   1402         }
   1403 
   1404         // If this is a promoted vector load, and the vector element types are
   1405         // illegal, create the promoted vector from bitcasted segments.
   1406         if (ExtType == ISD::EXTLOAD && SrcVT.isVector()) {
   1407           EVT MemElemTy = Node->getValueType(0).getScalarType();
   1408           EVT SrcSclrTy = SrcVT.getScalarType();
   1409           unsigned SizeRatio =
   1410             (MemElemTy.getSizeInBits() / SrcSclrTy.getSizeInBits());
   1411 
   1412           SmallVector<SDValue, 8> LoadVals;
   1413           SmallVector<SDValue, 8> LoadChains;
   1414           unsigned NumElem = SrcVT.getVectorNumElements();
   1415           unsigned Stride = SrcVT.getScalarType().getSizeInBits()/8;
   1416 
   1417           for (unsigned Idx=0; Idx<NumElem; Idx++) {
   1418             Tmp2 = DAG.getNode(ISD::ADD, dl, Tmp2.getValueType(), Tmp2,
   1419                                 DAG.getIntPtrConstant(Stride));
   1420             SDValue ScalarLoad = DAG.getExtLoad(ISD::EXTLOAD, dl,
   1421                   SrcVT.getScalarType(),
   1422                   Tmp1, Tmp2, LD->getPointerInfo().getWithOffset(Idx * Stride),
   1423                   SrcVT.getScalarType(),
   1424                   LD->isVolatile(), LD->isNonTemporal(),
   1425                   LD->getAlignment());
   1426             if (TLI.isBigEndian()) {
   1427               // MSB (which is garbage, comes first)
   1428               LoadVals.push_back(ScalarLoad.getValue(0));
   1429               for (unsigned i = 0; i<SizeRatio-1; ++i)
   1430                 LoadVals.push_back(DAG.getUNDEF(SrcVT.getScalarType()));
   1431             } else {
   1432               // LSB (which is data, comes first)
   1433               for (unsigned i = 0; i<SizeRatio-1; ++i)
   1434                 LoadVals.push_back(DAG.getUNDEF(SrcVT.getScalarType()));
   1435               LoadVals.push_back(ScalarLoad.getValue(0));
   1436             }
   1437             LoadChains.push_back(ScalarLoad.getValue(1));
   1438           }
   1439 
   1440           Result = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
   1441             &LoadChains[0], LoadChains.size());
   1442           EVT TempWideVector = EVT::getVectorVT(*DAG.getContext(),
   1443             SrcVT.getScalarType(), NumElem*SizeRatio);
   1444           SDValue ValRes = DAG.getNode(ISD::BUILD_VECTOR, dl,
   1445             TempWideVector, &LoadVals[0], LoadVals.size());
   1446 
   1447           // Cast to the correct type
   1448           ValRes = DAG.getNode(ISD::BITCAST, dl, Node->getValueType(0), ValRes);
   1449 
   1450           Tmp1 = LegalizeOp(ValRes);  // Relegalize new nodes.
   1451           Tmp2 = LegalizeOp(Result.getValue(0));  // Relegalize new nodes.
   1452           break;
   1453 
   1454         }
   1455 
   1456         // FIXME: This does not work for vectors on most targets.  Sign- and
   1457         // zero-extend operations are currently folded into extending loads,
   1458         // whether they are legal or not, and then we end up here without any
   1459         // support for legalizing them.
   1460         assert(ExtType != ISD::EXTLOAD &&
   1461                "EXTLOAD should always be supported!");
   1462         // Turn the unsupported load into an EXTLOAD followed by an explicit
   1463         // zero/sign extend inreg.
   1464         Result = DAG.getExtLoad(ISD::EXTLOAD, dl, Node->getValueType(0),
   1465                                 Tmp1, Tmp2, LD->getPointerInfo(), SrcVT,
   1466                                 LD->isVolatile(), LD->isNonTemporal(),
   1467                                 LD->getAlignment());
   1468         SDValue ValRes;
   1469         if (ExtType == ISD::SEXTLOAD)
   1470           ValRes = DAG.getNode(ISD::SIGN_EXTEND_INREG, dl,
   1471                                Result.getValueType(),
   1472                                Result, DAG.getValueType(SrcVT));
   1473         else
   1474           ValRes = DAG.getZeroExtendInReg(Result, dl, SrcVT.getScalarType());
   1475         Tmp1 = LegalizeOp(ValRes);  // Relegalize new nodes.
   1476         Tmp2 = LegalizeOp(Result.getValue(1));  // Relegalize new nodes.
   1477         break;
   1478       }
   1479     }
   1480 
   1481     // Since loads produce two values, make sure to remember that we legalized
   1482     // both of them.
   1483     AddLegalizedOperand(SDValue(Node, 0), Tmp1);
   1484     AddLegalizedOperand(SDValue(Node, 1), Tmp2);
   1485     return Op.getResNo() ? Tmp2 : Tmp1;
   1486   }
   1487   case ISD::STORE: {
   1488     StoreSDNode *ST = cast<StoreSDNode>(Node);
   1489     Tmp1 = LegalizeOp(ST->getChain());    // Legalize the chain.
   1490     Tmp2 = LegalizeOp(ST->getBasePtr());  // Legalize the pointer.
   1491     unsigned Alignment = ST->getAlignment();
   1492     bool isVolatile = ST->isVolatile();
   1493     bool isNonTemporal = ST->isNonTemporal();
   1494 
   1495     if (!ST->isTruncatingStore()) {
   1496       if (SDNode *OptStore = OptimizeFloatStore(ST).getNode()) {
   1497         Result = SDValue(OptStore, 0);
   1498         break;
   1499       }
   1500 
   1501       {
   1502         Tmp3 = LegalizeOp(ST->getValue());
   1503         Result = SDValue(DAG.UpdateNodeOperands(Result.getNode(),
   1504                                                 Tmp1, Tmp3, Tmp2,
   1505                                                 ST->getOffset()),
   1506                          Result.getResNo());
   1507 
   1508         EVT VT = Tmp3.getValueType();
   1509         switch (TLI.getOperationAction(ISD::STORE, VT)) {
   1510         default: assert(0 && "This action is not supported yet!");
   1511         case TargetLowering::Legal:
   1512           // If this is an unaligned store and the target doesn't support it,
   1513           // expand it.
   1514           if (!TLI.allowsUnalignedMemoryAccesses(ST->getMemoryVT())) {
   1515             Type *Ty = ST->getMemoryVT().getTypeForEVT(*DAG.getContext());
   1516             unsigned ABIAlignment= TLI.getTargetData()->getABITypeAlignment(Ty);
   1517             if (ST->getAlignment() < ABIAlignment)
   1518               Result = ExpandUnalignedStore(cast<StoreSDNode>(Result.getNode()),
   1519                                             DAG, TLI);
   1520           }
   1521           break;
   1522         case TargetLowering::Custom:
   1523           Tmp1 = TLI.LowerOperation(Result, DAG);
   1524           if (Tmp1.getNode()) Result = Tmp1;
   1525           break;
   1526         case TargetLowering::Promote:
   1527           assert(VT.isVector() && "Unknown legal promote case!");
   1528           Tmp3 = DAG.getNode(ISD::BITCAST, dl,
   1529                              TLI.getTypeToPromoteTo(ISD::STORE, VT), Tmp3);
   1530           Result = DAG.getStore(Tmp1, dl, Tmp3, Tmp2,
   1531                                 ST->getPointerInfo(), isVolatile,
   1532                                 isNonTemporal, Alignment);
   1533           break;
   1534         }
   1535         break;
   1536       }
   1537     } else {
   1538       Tmp3 = LegalizeOp(ST->getValue());
   1539 
   1540       EVT StVT = ST->getMemoryVT();
   1541       unsigned StWidth = StVT.getSizeInBits();
   1542 
   1543       if (StWidth != StVT.getStoreSizeInBits()) {
   1544         // Promote to a byte-sized store with upper bits zero if not
   1545         // storing an integral number of bytes.  For example, promote
   1546         // TRUNCSTORE:i1 X -> TRUNCSTORE:i8 (and X, 1)
   1547         EVT NVT = EVT::getIntegerVT(*DAG.getContext(),
   1548                                     StVT.getStoreSizeInBits());
   1549         Tmp3 = DAG.getZeroExtendInReg(Tmp3, dl, StVT);
   1550         Result = DAG.getTruncStore(Tmp1, dl, Tmp3, Tmp2, ST->getPointerInfo(),
   1551                                    NVT, isVolatile, isNonTemporal, Alignment);
   1552       } else if (StWidth & (StWidth - 1)) {
   1553         // If not storing a power-of-2 number of bits, expand as two stores.
   1554         assert(!StVT.isVector() && "Unsupported truncstore!");
   1555         unsigned RoundWidth = 1 << Log2_32(StWidth);
   1556         assert(RoundWidth < StWidth);
   1557         unsigned ExtraWidth = StWidth - RoundWidth;
   1558         assert(ExtraWidth < RoundWidth);
   1559         assert(!(RoundWidth % 8) && !(ExtraWidth % 8) &&
   1560                "Store size not an integral number of bytes!");
   1561         EVT RoundVT = EVT::getIntegerVT(*DAG.getContext(), RoundWidth);
   1562         EVT ExtraVT = EVT::getIntegerVT(*DAG.getContext(), ExtraWidth);
   1563         SDValue Lo, Hi;
   1564         unsigned IncrementSize;
   1565 
   1566         if (TLI.isLittleEndian()) {
   1567           // TRUNCSTORE:i24 X -> TRUNCSTORE:i16 X, TRUNCSTORE@+2:i8 (srl X, 16)
   1568           // Store the bottom RoundWidth bits.
   1569           Lo = DAG.getTruncStore(Tmp1, dl, Tmp3, Tmp2, ST->getPointerInfo(),
   1570                                  RoundVT,
   1571                                  isVolatile, isNonTemporal, Alignment);
   1572 
   1573           // Store the remaining ExtraWidth bits.
   1574           IncrementSize = RoundWidth / 8;
   1575           Tmp2 = DAG.getNode(ISD::ADD, dl, Tmp2.getValueType(), Tmp2,
   1576                              DAG.getIntPtrConstant(IncrementSize));
   1577           Hi = DAG.getNode(ISD::SRL, dl, Tmp3.getValueType(), Tmp3,
   1578                            DAG.getConstant(RoundWidth,
   1579                                     TLI.getShiftAmountTy(Tmp3.getValueType())));
   1580           Hi = DAG.getTruncStore(Tmp1, dl, Hi, Tmp2,
   1581                              ST->getPointerInfo().getWithOffset(IncrementSize),
   1582                                  ExtraVT, isVolatile, isNonTemporal,
   1583                                  MinAlign(Alignment, IncrementSize));
   1584         } else {
   1585           // Big endian - avoid unaligned stores.
   1586           // TRUNCSTORE:i24 X -> TRUNCSTORE:i16 (srl X, 8), TRUNCSTORE@+2:i8 X
   1587           // Store the top RoundWidth bits.
   1588           Hi = DAG.getNode(ISD::SRL, dl, Tmp3.getValueType(), Tmp3,
   1589                            DAG.getConstant(ExtraWidth,
   1590                                     TLI.getShiftAmountTy(Tmp3.getValueType())));
   1591           Hi = DAG.getTruncStore(Tmp1, dl, Hi, Tmp2, ST->getPointerInfo(),
   1592                                  RoundVT, isVolatile, isNonTemporal, Alignment);
   1593 
   1594           // Store the remaining ExtraWidth bits.
   1595           IncrementSize = RoundWidth / 8;
   1596           Tmp2 = DAG.getNode(ISD::ADD, dl, Tmp2.getValueType(), Tmp2,
   1597                              DAG.getIntPtrConstant(IncrementSize));
   1598           Lo = DAG.getTruncStore(Tmp1, dl, Tmp3, Tmp2,
   1599                               ST->getPointerInfo().getWithOffset(IncrementSize),
   1600                                  ExtraVT, isVolatile, isNonTemporal,
   1601                                  MinAlign(Alignment, IncrementSize));
   1602         }
   1603 
   1604         // The order of the stores doesn't matter.
   1605         Result = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
   1606       } else {
   1607         if (Tmp1 != ST->getChain() || Tmp3 != ST->getValue() ||
   1608             Tmp2 != ST->getBasePtr())
   1609           Result = SDValue(DAG.UpdateNodeOperands(Result.getNode(),
   1610                                                   Tmp1, Tmp3, Tmp2,
   1611                                                   ST->getOffset()),
   1612                            Result.getResNo());
   1613 
   1614         switch (TLI.getTruncStoreAction(ST->getValue().getValueType(), StVT)) {
   1615         default: assert(0 && "This action is not supported yet!");
   1616         case TargetLowering::Legal:
   1617           // If this is an unaligned store and the target doesn't support it,
   1618           // expand it.
   1619           if (!TLI.allowsUnalignedMemoryAccesses(ST->getMemoryVT())) {
   1620             Type *Ty = ST->getMemoryVT().getTypeForEVT(*DAG.getContext());
   1621             unsigned ABIAlignment= TLI.getTargetData()->getABITypeAlignment(Ty);
   1622             if (ST->getAlignment() < ABIAlignment)
   1623               Result = ExpandUnalignedStore(cast<StoreSDNode>(Result.getNode()),
   1624                                             DAG, TLI);
   1625           }
   1626           break;
   1627         case TargetLowering::Custom:
   1628           Result = TLI.LowerOperation(Result, DAG);
   1629           break;
   1630         case TargetLowering::Expand:
   1631 
   1632           EVT WideScalarVT = Tmp3.getValueType().getScalarType();
   1633           EVT NarrowScalarVT = StVT.getScalarType();
   1634 
   1635           if (StVT.isVector()) {
   1636             unsigned NumElem = StVT.getVectorNumElements();
   1637             // The type of the data we want to save
   1638             EVT RegVT = Tmp3.getValueType();
   1639             EVT RegSclVT = RegVT.getScalarType();
   1640             // The type of data as saved in memory.
   1641             EVT MemSclVT = StVT.getScalarType();
   1642 
   1643             bool RegScalarLegal = TLI.isTypeLegal(RegSclVT);
   1644             bool MemScalarLegal = TLI.isTypeLegal(MemSclVT);
   1645 
   1646             // We need to expand this store. If the register element type
   1647             // is legal then we can scalarize the vector and use
   1648             // truncating stores.
   1649             if (RegScalarLegal) {
   1650               // Cast floats into integers
   1651               unsigned ScalarSize = MemSclVT.getSizeInBits();
   1652               EVT EltVT = EVT::getIntegerVT(*DAG.getContext(), ScalarSize);
   1653 
   1654               // Round odd types to the next pow of two.
   1655               if (!isPowerOf2_32(ScalarSize))
   1656                 ScalarSize = NextPowerOf2(ScalarSize);
   1657 
   1658               // Store Stride in bytes
   1659               unsigned Stride = ScalarSize/8;
   1660               // Extract each of the elements from the original vector
   1661               // and save them into memory individually.
   1662               SmallVector<SDValue, 8> Stores;
   1663               for (unsigned Idx = 0; Idx < NumElem; Idx++) {
   1664                 SDValue Ex = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl,
   1665                                 RegSclVT, Tmp3, DAG.getIntPtrConstant(Idx));
   1666 
   1667                 Tmp2 = DAG.getNode(ISD::ADD, dl, Tmp2.getValueType(), Tmp2,
   1668                                    DAG.getIntPtrConstant(Stride));
   1669 
   1670                 // This scalar TruncStore may be illegal, but we lehalize it
   1671                 // later.
   1672                 SDValue Store = DAG.getTruncStore(Tmp1, dl, Ex, Tmp2,
   1673                       ST->getPointerInfo().getWithOffset(Idx*Stride), MemSclVT,
   1674                       isVolatile, isNonTemporal, Alignment);
   1675 
   1676                 Stores.push_back(Store);
   1677               }
   1678 
   1679               Result = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
   1680                                    &Stores[0], Stores.size());
   1681               break;
   1682             }
   1683 
   1684             // The scalar register type is illegal.
   1685             // For example saving <2 x i64> -> <2 x i32> on a x86.
   1686             // In here we bitcast the value into a vector of smaller parts and
   1687             // save it using smaller scalars.
   1688             if (!RegScalarLegal && MemScalarLegal) {
   1689               // Store Stride in bytes
   1690               unsigned Stride = MemSclVT.getSizeInBits()/8;
   1691 
   1692               unsigned SizeRatio =
   1693                 (RegSclVT.getSizeInBits() / MemSclVT.getSizeInBits());
   1694 
   1695               EVT CastValueVT = EVT::getVectorVT(*DAG.getContext(),
   1696                                                  MemSclVT,
   1697                                                  SizeRatio * NumElem);
   1698 
   1699               // Cast the wide elem vector to wider vec with smaller elem type.
   1700               // Example <2 x i64> -> <4 x i32>
   1701               Tmp3 = DAG.getNode(ISD::BITCAST, dl, CastValueVT, Tmp3);
   1702 
   1703               SmallVector<SDValue, 8> Stores;
   1704               for (unsigned Idx=0; Idx < NumElem * SizeRatio; Idx++) {
   1705                 // Extract the Ith element.
   1706                 SDValue Ex = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl,
   1707                                NarrowScalarVT, Tmp3, DAG.getIntPtrConstant(Idx));
   1708                 // Bump pointer.
   1709                 Tmp2 = DAG.getNode(ISD::ADD, dl, Tmp2.getValueType(), Tmp2,
   1710                                    DAG.getIntPtrConstant(Stride));
   1711 
   1712                 // Store if, this element is:
   1713                 //  - First element on big endian, or
   1714                 //  - Last element on little endian
   1715                 if (( TLI.isBigEndian() && (Idx % SizeRatio == 0)) ||
   1716                     ((!TLI.isBigEndian() && (Idx % SizeRatio == SizeRatio-1)))) {
   1717                   SDValue Store = DAG.getStore(Tmp1, dl, Ex, Tmp2,
   1718                                   ST->getPointerInfo().getWithOffset(Idx*Stride),
   1719                                            isVolatile, isNonTemporal, Alignment);
   1720                   Stores.push_back(Store);
   1721                 }
   1722               }
   1723               Result = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
   1724                                    &Stores[0], Stores.size());
   1725               break;
   1726             }
   1727 
   1728             assert(false && "Unable to legalize the vector trunc store!");
   1729           }// is vector
   1730 
   1731 
   1732           // TRUNCSTORE:i16 i32 -> STORE i16
   1733           assert(TLI.isTypeLegal(StVT) && "Do not know how to expand this store!");
   1734           Tmp3 = DAG.getNode(ISD::TRUNCATE, dl, StVT, Tmp3);
   1735           Result = DAG.getStore(Tmp1, dl, Tmp3, Tmp2, ST->getPointerInfo(),
   1736                                 isVolatile, isNonTemporal, Alignment);
   1737           break;
   1738         }
   1739       }
   1740     }
   1741     break;
   1742   }
   1743   }
   1744   assert(Result.getValueType() == Op.getValueType() &&
   1745          "Bad legalization!");
   1746 
   1747   // Make sure that the generated code is itself legal.
   1748   if (Result != Op)
   1749     Result = LegalizeOp(Result);
   1750 
   1751   // Note that LegalizeOp may be reentered even from single-use nodes, which
   1752   // means that we always must cache transformed nodes.
   1753   AddLegalizedOperand(Op, Result);
   1754   return Result;
   1755 }
   1756 
   1757 SDValue SelectionDAGLegalize::ExpandExtractFromVectorThroughStack(SDValue Op) {
   1758   SDValue Vec = Op.getOperand(0);
   1759   SDValue Idx = Op.getOperand(1);
   1760   DebugLoc dl = Op.getDebugLoc();
   1761   // Store the value to a temporary stack slot, then LOAD the returned part.
   1762   SDValue StackPtr = DAG.CreateStackTemporary(Vec.getValueType());
   1763   SDValue Ch = DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr,
   1764                             MachinePointerInfo(), false, false, 0);
   1765 
   1766   // Add the offset to the index.
   1767   unsigned EltSize =
   1768       Vec.getValueType().getVectorElementType().getSizeInBits()/8;
   1769   Idx = DAG.getNode(ISD::MUL, dl, Idx.getValueType(), Idx,
   1770                     DAG.getConstant(EltSize, Idx.getValueType()));
   1771 
   1772   if (Idx.getValueType().bitsGT(TLI.getPointerTy()))
   1773     Idx = DAG.getNode(ISD::TRUNCATE, dl, TLI.getPointerTy(), Idx);
   1774   else
   1775     Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
   1776 
   1777   StackPtr = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, StackPtr);
   1778 
   1779   if (Op.getValueType().isVector())
   1780     return DAG.getLoad(Op.getValueType(), dl, Ch, StackPtr,MachinePointerInfo(),
   1781                        false, false, 0);
   1782   return DAG.getExtLoad(ISD::EXTLOAD, dl, Op.getValueType(), Ch, StackPtr,
   1783                         MachinePointerInfo(),
   1784                         Vec.getValueType().getVectorElementType(),
   1785                         false, false, 0);
   1786 }
   1787 
   1788 SDValue SelectionDAGLegalize::ExpandInsertToVectorThroughStack(SDValue Op) {
   1789   assert(Op.getValueType().isVector() && "Non-vector insert subvector!");
   1790 
   1791   SDValue Vec  = Op.getOperand(0);
   1792   SDValue Part = Op.getOperand(1);
   1793   SDValue Idx  = Op.getOperand(2);
   1794   DebugLoc dl  = Op.getDebugLoc();
   1795 
   1796   // Store the value to a temporary stack slot, then LOAD the returned part.
   1797 
   1798   SDValue StackPtr = DAG.CreateStackTemporary(Vec.getValueType());
   1799   int FI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
   1800   MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(FI);
   1801 
   1802   // First store the whole vector.
   1803   SDValue Ch = DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr, PtrInfo,
   1804                             false, false, 0);
   1805 
   1806   // Then store the inserted part.
   1807 
   1808   // Add the offset to the index.
   1809   unsigned EltSize =
   1810       Vec.getValueType().getVectorElementType().getSizeInBits()/8;
   1811 
   1812   Idx = DAG.getNode(ISD::MUL, dl, Idx.getValueType(), Idx,
   1813                     DAG.getConstant(EltSize, Idx.getValueType()));
   1814 
   1815   if (Idx.getValueType().bitsGT(TLI.getPointerTy()))
   1816     Idx = DAG.getNode(ISD::TRUNCATE, dl, TLI.getPointerTy(), Idx);
   1817   else
   1818     Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
   1819 
   1820   SDValue SubStackPtr = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx,
   1821                                     StackPtr);
   1822 
   1823   // Store the subvector.
   1824   Ch = DAG.getStore(DAG.getEntryNode(), dl, Part, SubStackPtr,
   1825                     MachinePointerInfo(), false, false, 0);
   1826 
   1827   // Finally, load the updated vector.
   1828   return DAG.getLoad(Op.getValueType(), dl, Ch, StackPtr, PtrInfo,
   1829                      false, false, 0);
   1830 }
   1831 
   1832 SDValue SelectionDAGLegalize::ExpandVectorBuildThroughStack(SDNode* Node) {
   1833   // We can't handle this case efficiently.  Allocate a sufficiently
   1834   // aligned object on the stack, store each element into it, then load
   1835   // the result as a vector.
   1836   // Create the stack frame object.
   1837   EVT VT = Node->getValueType(0);
   1838   EVT EltVT = VT.getVectorElementType();
   1839   DebugLoc dl = Node->getDebugLoc();
   1840   SDValue FIPtr = DAG.CreateStackTemporary(VT);
   1841   int FI = cast<FrameIndexSDNode>(FIPtr.getNode())->getIndex();
   1842   MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(FI);
   1843 
   1844   // Emit a store of each element to the stack slot.
   1845   SmallVector<SDValue, 8> Stores;
   1846   unsigned TypeByteSize = EltVT.getSizeInBits() / 8;
   1847   // Store (in the right endianness) the elements to memory.
   1848   for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
   1849     // Ignore undef elements.
   1850     if (Node->getOperand(i).getOpcode() == ISD::UNDEF) continue;
   1851 
   1852     unsigned Offset = TypeByteSize*i;
   1853 
   1854     SDValue Idx = DAG.getConstant(Offset, FIPtr.getValueType());
   1855     Idx = DAG.getNode(ISD::ADD, dl, FIPtr.getValueType(), FIPtr, Idx);
   1856 
   1857     // If the destination vector element type is narrower than the source
   1858     // element type, only store the bits necessary.
   1859     if (EltVT.bitsLT(Node->getOperand(i).getValueType().getScalarType())) {
   1860       Stores.push_back(DAG.getTruncStore(DAG.getEntryNode(), dl,
   1861                                          Node->getOperand(i), Idx,
   1862                                          PtrInfo.getWithOffset(Offset),
   1863                                          EltVT, false, false, 0));
   1864     } else
   1865       Stores.push_back(DAG.getStore(DAG.getEntryNode(), dl,
   1866                                     Node->getOperand(i), Idx,
   1867                                     PtrInfo.getWithOffset(Offset),
   1868                                     false, false, 0));
   1869   }
   1870 
   1871   SDValue StoreChain;
   1872   if (!Stores.empty())    // Not all undef elements?
   1873     StoreChain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
   1874                              &Stores[0], Stores.size());
   1875   else
   1876     StoreChain = DAG.getEntryNode();
   1877 
   1878   // Result is a load from the stack slot.
   1879   return DAG.getLoad(VT, dl, StoreChain, FIPtr, PtrInfo, false, false, 0);
   1880 }
   1881 
   1882 SDValue SelectionDAGLegalize::ExpandFCOPYSIGN(SDNode* Node) {
   1883   DebugLoc dl = Node->getDebugLoc();
   1884   SDValue Tmp1 = Node->getOperand(0);
   1885   SDValue Tmp2 = Node->getOperand(1);
   1886 
   1887   // Get the sign bit of the RHS.  First obtain a value that has the same
   1888   // sign as the sign bit, i.e. negative if and only if the sign bit is 1.
   1889   SDValue SignBit;
   1890   EVT FloatVT = Tmp2.getValueType();
   1891   EVT IVT = EVT::getIntegerVT(*DAG.getContext(), FloatVT.getSizeInBits());
   1892   if (TLI.isTypeLegal(IVT)) {
   1893     // Convert to an integer with the same sign bit.
   1894     SignBit = DAG.getNode(ISD::BITCAST, dl, IVT, Tmp2);
   1895   } else {
   1896     // Store the float to memory, then load the sign part out as an integer.
   1897     MVT LoadTy = TLI.getPointerTy();
   1898     // First create a temporary that is aligned for both the load and store.
   1899     SDValue StackPtr = DAG.CreateStackTemporary(FloatVT, LoadTy);
   1900     // Then store the float to it.
   1901     SDValue Ch =
   1902       DAG.getStore(DAG.getEntryNode(), dl, Tmp2, StackPtr, MachinePointerInfo(),
   1903                    false, false, 0);
   1904     if (TLI.isBigEndian()) {
   1905       assert(FloatVT.isByteSized() && "Unsupported floating point type!");
   1906       // Load out a legal integer with the same sign bit as the float.
   1907       SignBit = DAG.getLoad(LoadTy, dl, Ch, StackPtr, MachinePointerInfo(),
   1908                             false, false, 0);
   1909     } else { // Little endian
   1910       SDValue LoadPtr = StackPtr;
   1911       // The float may be wider than the integer we are going to load.  Advance
   1912       // the pointer so that the loaded integer will contain the sign bit.
   1913       unsigned Strides = (FloatVT.getSizeInBits()-1)/LoadTy.getSizeInBits();
   1914       unsigned ByteOffset = (Strides * LoadTy.getSizeInBits()) / 8;
   1915       LoadPtr = DAG.getNode(ISD::ADD, dl, LoadPtr.getValueType(),
   1916                             LoadPtr, DAG.getIntPtrConstant(ByteOffset));
   1917       // Load a legal integer containing the sign bit.
   1918       SignBit = DAG.getLoad(LoadTy, dl, Ch, LoadPtr, MachinePointerInfo(),
   1919                             false, false, 0);
   1920       // Move the sign bit to the top bit of the loaded integer.
   1921       unsigned BitShift = LoadTy.getSizeInBits() -
   1922         (FloatVT.getSizeInBits() - 8 * ByteOffset);
   1923       assert(BitShift < LoadTy.getSizeInBits() && "Pointer advanced wrong?");
   1924       if (BitShift)
   1925         SignBit = DAG.getNode(ISD::SHL, dl, LoadTy, SignBit,
   1926                               DAG.getConstant(BitShift,
   1927                                  TLI.getShiftAmountTy(SignBit.getValueType())));
   1928     }
   1929   }
   1930   // Now get the sign bit proper, by seeing whether the value is negative.
   1931   SignBit = DAG.getSetCC(dl, TLI.getSetCCResultType(SignBit.getValueType()),
   1932                          SignBit, DAG.getConstant(0, SignBit.getValueType()),
   1933                          ISD::SETLT);
   1934   // Get the absolute value of the result.
   1935   SDValue AbsVal = DAG.getNode(ISD::FABS, dl, Tmp1.getValueType(), Tmp1);
   1936   // Select between the nabs and abs value based on the sign bit of
   1937   // the input.
   1938   return DAG.getNode(ISD::SELECT, dl, AbsVal.getValueType(), SignBit,
   1939                      DAG.getNode(ISD::FNEG, dl, AbsVal.getValueType(), AbsVal),
   1940                      AbsVal);
   1941 }
   1942 
   1943 void SelectionDAGLegalize::ExpandDYNAMIC_STACKALLOC(SDNode* Node,
   1944                                            SmallVectorImpl<SDValue> &Results) {
   1945   unsigned SPReg = TLI.getStackPointerRegisterToSaveRestore();
   1946   assert(SPReg && "Target cannot require DYNAMIC_STACKALLOC expansion and"
   1947           " not tell us which reg is the stack pointer!");
   1948   DebugLoc dl = Node->getDebugLoc();
   1949   EVT VT = Node->getValueType(0);
   1950   SDValue Tmp1 = SDValue(Node, 0);
   1951   SDValue Tmp2 = SDValue(Node, 1);
   1952   SDValue Tmp3 = Node->getOperand(2);
   1953   SDValue Chain = Tmp1.getOperand(0);
   1954 
   1955   // Chain the dynamic stack allocation so that it doesn't modify the stack
   1956   // pointer when other instructions are using the stack.
   1957   Chain = DAG.getCALLSEQ_START(Chain, DAG.getIntPtrConstant(0, true));
   1958 
   1959   SDValue Size  = Tmp2.getOperand(1);
   1960   SDValue SP = DAG.getCopyFromReg(Chain, dl, SPReg, VT);
   1961   Chain = SP.getValue(1);
   1962   unsigned Align = cast<ConstantSDNode>(Tmp3)->getZExtValue();
   1963   unsigned StackAlign = TM.getFrameLowering()->getStackAlignment();
   1964   if (Align > StackAlign)
   1965     SP = DAG.getNode(ISD::AND, dl, VT, SP,
   1966                       DAG.getConstant(-(uint64_t)Align, VT));
   1967   Tmp1 = DAG.getNode(ISD::SUB, dl, VT, SP, Size);       // Value
   1968   Chain = DAG.getCopyToReg(Chain, dl, SPReg, Tmp1);     // Output chain
   1969 
   1970   Tmp2 = DAG.getCALLSEQ_END(Chain,  DAG.getIntPtrConstant(0, true),
   1971                             DAG.getIntPtrConstant(0, true), SDValue());
   1972 
   1973   Results.push_back(Tmp1);
   1974   Results.push_back(Tmp2);
   1975 }
   1976 
   1977 /// LegalizeSetCCCondCode - Legalize a SETCC with given LHS and RHS and
   1978 /// condition code CC on the current target. This routine expands SETCC with
   1979 /// illegal condition code into AND / OR of multiple SETCC values.
   1980 void SelectionDAGLegalize::LegalizeSetCCCondCode(EVT VT,
   1981                                                  SDValue &LHS, SDValue &RHS,
   1982                                                  SDValue &CC,
   1983                                                  DebugLoc dl) {
   1984   EVT OpVT = LHS.getValueType();
   1985   ISD::CondCode CCCode = cast<CondCodeSDNode>(CC)->get();
   1986   switch (TLI.getCondCodeAction(CCCode, OpVT)) {
   1987   default: assert(0 && "Unknown condition code action!");
   1988   case TargetLowering::Legal:
   1989     // Nothing to do.
   1990     break;
   1991   case TargetLowering::Expand: {
   1992     ISD::CondCode CC1 = ISD::SETCC_INVALID, CC2 = ISD::SETCC_INVALID;
   1993     unsigned Opc = 0;
   1994     switch (CCCode) {
   1995     default: assert(0 && "Don't know how to expand this condition!");
   1996     case ISD::SETOEQ: CC1 = ISD::SETEQ; CC2 = ISD::SETO;  Opc = ISD::AND; break;
   1997     case ISD::SETOGT: CC1 = ISD::SETGT; CC2 = ISD::SETO;  Opc = ISD::AND; break;
   1998     case ISD::SETOGE: CC1 = ISD::SETGE; CC2 = ISD::SETO;  Opc = ISD::AND; break;
   1999     case ISD::SETOLT: CC1 = ISD::SETLT; CC2 = ISD::SETO;  Opc = ISD::AND; break;
   2000     case ISD::SETOLE: CC1 = ISD::SETLE; CC2 = ISD::SETO;  Opc = ISD::AND; break;
   2001     case ISD::SETONE: CC1 = ISD::SETNE; CC2 = ISD::SETO;  Opc = ISD::AND; break;
   2002     case ISD::SETUEQ: CC1 = ISD::SETEQ; CC2 = ISD::SETUO; Opc = ISD::OR;  break;
   2003     case ISD::SETUGT: CC1 = ISD::SETGT; CC2 = ISD::SETUO; Opc = ISD::OR;  break;
   2004     case ISD::SETUGE: CC1 = ISD::SETGE; CC2 = ISD::SETUO; Opc = ISD::OR;  break;
   2005     case ISD::SETULT: CC1 = ISD::SETLT; CC2 = ISD::SETUO; Opc = ISD::OR;  break;
   2006     case ISD::SETULE: CC1 = ISD::SETLE; CC2 = ISD::SETUO; Opc = ISD::OR;  break;
   2007     case ISD::SETUNE: CC1 = ISD::SETNE; CC2 = ISD::SETUO; Opc = ISD::OR;  break;
   2008     // FIXME: Implement more expansions.
   2009     }
   2010 
   2011     SDValue SetCC1 = DAG.getSetCC(dl, VT, LHS, RHS, CC1);
   2012     SDValue SetCC2 = DAG.getSetCC(dl, VT, LHS, RHS, CC2);
   2013     LHS = DAG.getNode(Opc, dl, VT, SetCC1, SetCC2);
   2014     RHS = SDValue();
   2015     CC  = SDValue();
   2016     break;
   2017   }
   2018   }
   2019 }
   2020 
   2021 /// EmitStackConvert - Emit a store/load combination to the stack.  This stores
   2022 /// SrcOp to a stack slot of type SlotVT, truncating it if needed.  It then does
   2023 /// a load from the stack slot to DestVT, extending it if needed.
   2024 /// The resultant code need not be legal.
   2025 SDValue SelectionDAGLegalize::EmitStackConvert(SDValue SrcOp,
   2026                                                EVT SlotVT,
   2027                                                EVT DestVT,
   2028                                                DebugLoc dl) {
   2029   // Create the stack frame object.
   2030   unsigned SrcAlign =
   2031     TLI.getTargetData()->getPrefTypeAlignment(SrcOp.getValueType().
   2032                                               getTypeForEVT(*DAG.getContext()));
   2033   SDValue FIPtr = DAG.CreateStackTemporary(SlotVT, SrcAlign);
   2034 
   2035   FrameIndexSDNode *StackPtrFI = cast<FrameIndexSDNode>(FIPtr);
   2036   int SPFI = StackPtrFI->getIndex();
   2037   MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(SPFI);
   2038 
   2039   unsigned SrcSize = SrcOp.getValueType().getSizeInBits();
   2040   unsigned SlotSize = SlotVT.getSizeInBits();
   2041   unsigned DestSize = DestVT.getSizeInBits();
   2042   Type *DestType = DestVT.getTypeForEVT(*DAG.getContext());
   2043   unsigned DestAlign = TLI.getTargetData()->getPrefTypeAlignment(DestType);
   2044 
   2045   // Emit a store to the stack slot.  Use a truncstore if the input value is
   2046   // later than DestVT.
   2047   SDValue Store;
   2048 
   2049   if (SrcSize > SlotSize)
   2050     Store = DAG.getTruncStore(DAG.getEntryNode(), dl, SrcOp, FIPtr,
   2051                               PtrInfo, SlotVT, false, false, SrcAlign);
   2052   else {
   2053     assert(SrcSize == SlotSize && "Invalid store");
   2054     Store = DAG.getStore(DAG.getEntryNode(), dl, SrcOp, FIPtr,
   2055                          PtrInfo, false, false, SrcAlign);
   2056   }
   2057 
   2058   // Result is a load from the stack slot.
   2059   if (SlotSize == DestSize)
   2060     return DAG.getLoad(DestVT, dl, Store, FIPtr, PtrInfo,
   2061                        false, false, DestAlign);
   2062 
   2063   assert(SlotSize < DestSize && "Unknown extension!");
   2064   return DAG.getExtLoad(ISD::EXTLOAD, dl, DestVT, Store, FIPtr,
   2065                         PtrInfo, SlotVT, false, false, DestAlign);
   2066 }
   2067 
   2068 SDValue SelectionDAGLegalize::ExpandSCALAR_TO_VECTOR(SDNode *Node) {
   2069   DebugLoc dl = Node->getDebugLoc();
   2070   // Create a vector sized/aligned stack slot, store the value to element #0,
   2071   // then load the whole vector back out.
   2072   SDValue StackPtr = DAG.CreateStackTemporary(Node->getValueType(0));
   2073 
   2074   FrameIndexSDNode *StackPtrFI = cast<FrameIndexSDNode>(StackPtr);
   2075   int SPFI = StackPtrFI->getIndex();
   2076 
   2077   SDValue Ch = DAG.getTruncStore(DAG.getEntryNode(), dl, Node->getOperand(0),
   2078                                  StackPtr,
   2079                                  MachinePointerInfo::getFixedStack(SPFI),
   2080                                  Node->getValueType(0).getVectorElementType(),
   2081                                  false, false, 0);
   2082   return DAG.getLoad(Node->getValueType(0), dl, Ch, StackPtr,
   2083                      MachinePointerInfo::getFixedStack(SPFI),
   2084                      false, false, 0);
   2085 }
   2086 
   2087 
   2088 /// ExpandBUILD_VECTOR - Expand a BUILD_VECTOR node on targets that don't
   2089 /// support the operation, but do support the resultant vector type.
   2090 SDValue SelectionDAGLegalize::ExpandBUILD_VECTOR(SDNode *Node) {
   2091   unsigned NumElems = Node->getNumOperands();
   2092   SDValue Value1, Value2;
   2093   DebugLoc dl = Node->getDebugLoc();
   2094   EVT VT = Node->getValueType(0);
   2095   EVT OpVT = Node->getOperand(0).getValueType();
   2096   EVT EltVT = VT.getVectorElementType();
   2097 
   2098   // If the only non-undef value is the low element, turn this into a
   2099   // SCALAR_TO_VECTOR node.  If this is { X, X, X, X }, determine X.
   2100   bool isOnlyLowElement = true;
   2101   bool MoreThanTwoValues = false;
   2102   bool isConstant = true;
   2103   for (unsigned i = 0; i < NumElems; ++i) {
   2104     SDValue V = Node->getOperand(i);
   2105     if (V.getOpcode() == ISD::UNDEF)
   2106       continue;
   2107     if (i > 0)
   2108       isOnlyLowElement = false;
   2109     if (!isa<ConstantFPSDNode>(V) && !isa<ConstantSDNode>(V))
   2110       isConstant = false;
   2111 
   2112     if (!Value1.getNode()) {
   2113       Value1 = V;
   2114     } else if (!Value2.getNode()) {
   2115       if (V != Value1)
   2116         Value2 = V;
   2117     } else if (V != Value1 && V != Value2) {
   2118       MoreThanTwoValues = true;
   2119     }
   2120   }
   2121 
   2122   if (!Value1.getNode())
   2123     return DAG.getUNDEF(VT);
   2124 
   2125   if (isOnlyLowElement)
   2126     return DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Node->getOperand(0));
   2127 
   2128   // If all elements are constants, create a load from the constant pool.
   2129   if (isConstant) {
   2130     std::vector<Constant*> CV;
   2131     for (unsigned i = 0, e = NumElems; i != e; ++i) {
   2132       if (ConstantFPSDNode *V =
   2133           dyn_cast<ConstantFPSDNode>(Node->getOperand(i))) {
   2134         CV.push_back(const_cast<ConstantFP *>(V->getConstantFPValue()));
   2135       } else if (ConstantSDNode *V =
   2136                  dyn_cast<ConstantSDNode>(Node->getOperand(i))) {
   2137         if (OpVT==EltVT)
   2138           CV.push_back(const_cast<ConstantInt *>(V->getConstantIntValue()));
   2139         else {
   2140           // If OpVT and EltVT don't match, EltVT is not legal and the
   2141           // element values have been promoted/truncated earlier.  Undo this;
   2142           // we don't want a v16i8 to become a v16i32 for example.
   2143           const ConstantInt *CI = V->getConstantIntValue();
   2144           CV.push_back(ConstantInt::get(EltVT.getTypeForEVT(*DAG.getContext()),
   2145                                         CI->getZExtValue()));
   2146         }
   2147       } else {
   2148         assert(Node->getOperand(i).getOpcode() == ISD::UNDEF);
   2149         Type *OpNTy = EltVT.getTypeForEVT(*DAG.getContext());
   2150         CV.push_back(UndefValue::get(OpNTy));
   2151       }
   2152     }
   2153     Constant *CP = ConstantVector::get(CV);
   2154     SDValue CPIdx = DAG.getConstantPool(CP, TLI.getPointerTy());
   2155     unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
   2156     return DAG.getLoad(VT, dl, DAG.getEntryNode(), CPIdx,
   2157                        MachinePointerInfo::getConstantPool(),
   2158                        false, false, Alignment);
   2159   }
   2160 
   2161   if (!MoreThanTwoValues) {
   2162     SmallVector<int, 8> ShuffleVec(NumElems, -1);
   2163     for (unsigned i = 0; i < NumElems; ++i) {
   2164       SDValue V = Node->getOperand(i);
   2165       if (V.getOpcode() == ISD::UNDEF)
   2166         continue;
   2167       ShuffleVec[i] = V == Value1 ? 0 : NumElems;
   2168     }
   2169     if (TLI.isShuffleMaskLegal(ShuffleVec, Node->getValueType(0))) {
   2170       // Get the splatted value into the low element of a vector register.
   2171       SDValue Vec1 = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Value1);
   2172       SDValue Vec2;
   2173       if (Value2.getNode())
   2174         Vec2 = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Value2);
   2175       else
   2176         Vec2 = DAG.getUNDEF(VT);
   2177 
   2178       // Return shuffle(LowValVec, undef, <0,0,0,0>)
   2179       return DAG.getVectorShuffle(VT, dl, Vec1, Vec2, ShuffleVec.data());
   2180     }
   2181   }
   2182 
   2183   // Otherwise, we can't handle this case efficiently.
   2184   return ExpandVectorBuildThroughStack(Node);
   2185 }
   2186 
   2187 // ExpandLibCall - Expand a node into a call to a libcall.  If the result value
   2188 // does not fit into a register, return the lo part and set the hi part to the
   2189 // by-reg argument.  If it does fit into a single register, return the result
   2190 // and leave the Hi part unset.
   2191 SDValue SelectionDAGLegalize::ExpandLibCall(RTLIB::Libcall LC, SDNode *Node,
   2192                                             bool isSigned) {
   2193   assert(!IsLegalizingCall && "Cannot overlap legalization of calls!");
   2194   // The input chain to this libcall is the entry node of the function.
   2195   // Legalizing the call will automatically add the previous call to the
   2196   // dependence.
   2197   SDValue InChain = DAG.getEntryNode();
   2198 
   2199   TargetLowering::ArgListTy Args;
   2200   TargetLowering::ArgListEntry Entry;
   2201   for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
   2202     EVT ArgVT = Node->getOperand(i).getValueType();
   2203     Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
   2204     Entry.Node = Node->getOperand(i); Entry.Ty = ArgTy;
   2205     Entry.isSExt = isSigned;
   2206     Entry.isZExt = !isSigned;
   2207     Args.push_back(Entry);
   2208   }
   2209   SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
   2210                                          TLI.getPointerTy());
   2211 
   2212   // Splice the libcall in wherever FindInputOutputChains tells us to.
   2213   Type *RetTy = Node->getValueType(0).getTypeForEVT(*DAG.getContext());
   2214 
   2215   // isTailCall may be true since the callee does not reference caller stack
   2216   // frame. Check if it's in the right position.
   2217   bool isTailCall = isInTailCallPosition(DAG, Node, TLI);
   2218   std::pair<SDValue, SDValue> CallInfo =
   2219     TLI.LowerCallTo(InChain, RetTy, isSigned, !isSigned, false, false,
   2220                     0, TLI.getLibcallCallingConv(LC), isTailCall,
   2221                     /*isReturnValueUsed=*/true,
   2222                     Callee, Args, DAG, Node->getDebugLoc());
   2223 
   2224   if (!CallInfo.second.getNode())
   2225     // It's a tailcall, return the chain (which is the DAG root).
   2226     return DAG.getRoot();
   2227 
   2228   // Legalize the call sequence, starting with the chain.  This will advance
   2229   // the LastCALLSEQ_END to the legalized version of the CALLSEQ_END node that
   2230   // was added by LowerCallTo (guaranteeing proper serialization of calls).
   2231   LegalizeOp(CallInfo.second);
   2232   return CallInfo.first;
   2233 }
   2234 
   2235 /// ExpandLibCall - Generate a libcall taking the given operands as arguments
   2236 /// and returning a result of type RetVT.
   2237 SDValue SelectionDAGLegalize::ExpandLibCall(RTLIB::Libcall LC, EVT RetVT,
   2238                                             const SDValue *Ops, unsigned NumOps,
   2239                                             bool isSigned, DebugLoc dl) {
   2240   TargetLowering::ArgListTy Args;
   2241   Args.reserve(NumOps);
   2242 
   2243   TargetLowering::ArgListEntry Entry;
   2244   for (unsigned i = 0; i != NumOps; ++i) {
   2245     Entry.Node = Ops[i];
   2246     Entry.Ty = Entry.Node.getValueType().getTypeForEVT(*DAG.getContext());
   2247     Entry.isSExt = isSigned;
   2248     Entry.isZExt = !isSigned;
   2249     Args.push_back(Entry);
   2250   }
   2251   SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
   2252                                          TLI.getPointerTy());
   2253 
   2254   Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
   2255   std::pair<SDValue,SDValue> CallInfo =
   2256   TLI.LowerCallTo(DAG.getEntryNode(), RetTy, isSigned, !isSigned, false,
   2257                   false, 0, TLI.getLibcallCallingConv(LC), false,
   2258                   /*isReturnValueUsed=*/true,
   2259                   Callee, Args, DAG, dl);
   2260 
   2261   // Legalize the call sequence, starting with the chain.  This will advance
   2262   // the LastCALLSEQ_END to the legalized version of the CALLSEQ_END node that
   2263   // was added by LowerCallTo (guaranteeing proper serialization of calls).
   2264   LegalizeOp(CallInfo.second);
   2265 
   2266   return CallInfo.first;
   2267 }
   2268 
   2269 // ExpandChainLibCall - Expand a node into a call to a libcall. Similar to
   2270 // ExpandLibCall except that the first operand is the in-chain.
   2271 std::pair<SDValue, SDValue>
   2272 SelectionDAGLegalize::ExpandChainLibCall(RTLIB::Libcall LC,
   2273                                          SDNode *Node,
   2274                                          bool isSigned) {
   2275   assert(!IsLegalizingCall && "Cannot overlap legalization of calls!");
   2276   SDValue InChain = Node->getOperand(0);
   2277 
   2278   TargetLowering::ArgListTy Args;
   2279   TargetLowering::ArgListEntry Entry;
   2280   for (unsigned i = 1, e = Node->getNumOperands(); i != e; ++i) {
   2281     EVT ArgVT = Node->getOperand(i).getValueType();
   2282     Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
   2283     Entry.Node = Node->getOperand(i);
   2284     Entry.Ty = ArgTy;
   2285     Entry.isSExt = isSigned;
   2286     Entry.isZExt = !isSigned;
   2287     Args.push_back(Entry);
   2288   }
   2289   SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
   2290                                          TLI.getPointerTy());
   2291 
   2292   // Splice the libcall in wherever FindInputOutputChains tells us to.
   2293   Type *RetTy = Node->getValueType(0).getTypeForEVT(*DAG.getContext());
   2294   std::pair<SDValue, SDValue> CallInfo =
   2295     TLI.LowerCallTo(InChain, RetTy, isSigned, !isSigned, false, false,
   2296                     0, TLI.getLibcallCallingConv(LC), /*isTailCall=*/false,
   2297                     /*isReturnValueUsed=*/true,
   2298                     Callee, Args, DAG, Node->getDebugLoc());
   2299 
   2300   // Legalize the call sequence, starting with the chain.  This will advance
   2301   // the LastCALLSEQ_END to the legalized version of the CALLSEQ_END node that
   2302   // was added by LowerCallTo (guaranteeing proper serialization of calls).
   2303   LegalizeOp(CallInfo.second);
   2304   return CallInfo;
   2305 }
   2306 
   2307 SDValue SelectionDAGLegalize::ExpandFPLibCall(SDNode* Node,
   2308                                               RTLIB::Libcall Call_F32,
   2309                                               RTLIB::Libcall Call_F64,
   2310                                               RTLIB::Libcall Call_F80,
   2311                                               RTLIB::Libcall Call_PPCF128) {
   2312   RTLIB::Libcall LC;
   2313   switch (Node->getValueType(0).getSimpleVT().SimpleTy) {
   2314   default: assert(0 && "Unexpected request for libcall!");
   2315   case MVT::f32: LC = Call_F32; break;
   2316   case MVT::f64: LC = Call_F64; break;
   2317   case MVT::f80: LC = Call_F80; break;
   2318   case MVT::ppcf128: LC = Call_PPCF128; break;
   2319   }
   2320   return ExpandLibCall(LC, Node, false);
   2321 }
   2322 
   2323 SDValue SelectionDAGLegalize::ExpandIntLibCall(SDNode* Node, bool isSigned,
   2324                                                RTLIB::Libcall Call_I8,
   2325                                                RTLIB::Libcall Call_I16,
   2326                                                RTLIB::Libcall Call_I32,
   2327                                                RTLIB::Libcall Call_I64,
   2328                                                RTLIB::Libcall Call_I128) {
   2329   RTLIB::Libcall LC;
   2330   switch (Node->getValueType(0).getSimpleVT().SimpleTy) {
   2331   default: assert(0 && "Unexpected request for libcall!");
   2332   case MVT::i8:   LC = Call_I8; break;
   2333   case MVT::i16:  LC = Call_I16; break;
   2334   case MVT::i32:  LC = Call_I32; break;
   2335   case MVT::i64:  LC = Call_I64; break;
   2336   case MVT::i128: LC = Call_I128; break;
   2337   }
   2338   return ExpandLibCall(LC, Node, isSigned);
   2339 }
   2340 
   2341 /// isDivRemLibcallAvailable - Return true if divmod libcall is available.
   2342 static bool isDivRemLibcallAvailable(SDNode *Node, bool isSigned,
   2343                                      const TargetLowering &TLI) {
   2344   RTLIB::Libcall LC;
   2345   switch (Node->getValueType(0).getSimpleVT().SimpleTy) {
   2346   default: assert(0 && "Unexpected request for libcall!");
   2347   case MVT::i8:   LC= isSigned ? RTLIB::SDIVREM_I8  : RTLIB::UDIVREM_I8;  break;
   2348   case MVT::i16:  LC= isSigned ? RTLIB::SDIVREM_I16 : RTLIB::UDIVREM_I16; break;
   2349   case MVT::i32:  LC= isSigned ? RTLIB::SDIVREM_I32 : RTLIB::UDIVREM_I32; break;
   2350   case MVT::i64:  LC= isSigned ? RTLIB::SDIVREM_I64 : RTLIB::UDIVREM_I64; break;
   2351   case MVT::i128: LC= isSigned ? RTLIB::SDIVREM_I128:RTLIB::UDIVREM_I128; break;
   2352   }
   2353 
   2354   return TLI.getLibcallName(LC) != 0;
   2355 }
   2356 
   2357 /// UseDivRem - Only issue divrem libcall if both quotient and remainder are
   2358 /// needed.
   2359 static bool UseDivRem(SDNode *Node, bool isSigned, bool isDIV) {
   2360   unsigned OtherOpcode = 0;
   2361   if (isSigned)
   2362     OtherOpcode = isDIV ? ISD::SREM : ISD::SDIV;
   2363   else
   2364     OtherOpcode = isDIV ? ISD::UREM : ISD::UDIV;
   2365 
   2366   SDValue Op0 = Node->getOperand(0);
   2367   SDValue Op1 = Node->getOperand(1);
   2368   for (SDNode::use_iterator UI = Op0.getNode()->use_begin(),
   2369          UE = Op0.getNode()->use_end(); UI != UE; ++UI) {
   2370     SDNode *User = *UI;
   2371     if (User == Node)
   2372       continue;
   2373     if (User->getOpcode() == OtherOpcode &&
   2374         User->getOperand(0) == Op0 &&
   2375         User->getOperand(1) == Op1)
   2376       return true;
   2377   }
   2378   return false;
   2379 }
   2380 
   2381 /// ExpandDivRemLibCall - Issue libcalls to __{u}divmod to compute div / rem
   2382 /// pairs.
   2383 void
   2384 SelectionDAGLegalize::ExpandDivRemLibCall(SDNode *Node,
   2385                                           SmallVectorImpl<SDValue> &Results) {
   2386   unsigned Opcode = Node->getOpcode();
   2387   bool isSigned = Opcode == ISD::SDIVREM;
   2388 
   2389   RTLIB::Libcall LC;
   2390   switch (Node->getValueType(0).getSimpleVT().SimpleTy) {
   2391   default: assert(0 && "Unexpected request for libcall!");
   2392   case MVT::i8:   LC= isSigned ? RTLIB::SDIVREM_I8  : RTLIB::UDIVREM_I8;  break;
   2393   case MVT::i16:  LC= isSigned ? RTLIB::SDIVREM_I16 : RTLIB::UDIVREM_I16; break;
   2394   case MVT::i32:  LC= isSigned ? RTLIB::SDIVREM_I32 : RTLIB::UDIVREM_I32; break;
   2395   case MVT::i64:  LC= isSigned ? RTLIB::SDIVREM_I64 : RTLIB::UDIVREM_I64; break;
   2396   case MVT::i128: LC= isSigned ? RTLIB::SDIVREM_I128:RTLIB::UDIVREM_I128; break;
   2397   }
   2398 
   2399   // The input chain to this libcall is the entry node of the function.
   2400   // Legalizing the call will automatically add the previous call to the
   2401   // dependence.
   2402   SDValue InChain = DAG.getEntryNode();
   2403 
   2404   EVT RetVT = Node->getValueType(0);
   2405   Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
   2406 
   2407   TargetLowering::ArgListTy Args;
   2408   TargetLowering::ArgListEntry Entry;
   2409   for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
   2410     EVT ArgVT = Node->getOperand(i).getValueType();
   2411     Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
   2412     Entry.Node = Node->getOperand(i); Entry.Ty = ArgTy;
   2413     Entry.isSExt = isSigned;
   2414     Entry.isZExt = !isSigned;
   2415     Args.push_back(Entry);
   2416   }
   2417 
   2418   // Also pass the return address of the remainder.
   2419   SDValue FIPtr = DAG.CreateStackTemporary(RetVT);
   2420   Entry.Node = FIPtr;
   2421   Entry.Ty = RetTy->getPointerTo();
   2422   Entry.isSExt = isSigned;
   2423   Entry.isZExt = !isSigned;
   2424   Args.push_back(Entry);
   2425 
   2426   SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
   2427                                          TLI.getPointerTy());
   2428 
   2429   // Splice the libcall in wherever FindInputOutputChains tells us to.
   2430   DebugLoc dl = Node->getDebugLoc();
   2431   std::pair<SDValue, SDValue> CallInfo =
   2432     TLI.LowerCallTo(InChain, RetTy, isSigned, !isSigned, false, false,
   2433                     0, TLI.getLibcallCallingConv(LC), /*isTailCall=*/false,
   2434                     /*isReturnValueUsed=*/true, Callee, Args, DAG, dl);
   2435 
   2436   // Legalize the call sequence, starting with the chain.  This will advance
   2437   // the LastCALLSEQ to the legalized version of the CALLSEQ_END node that
   2438   // was added by LowerCallTo (guaranteeing proper serialization of calls).
   2439   LegalizeOp(CallInfo.second);
   2440 
   2441   // Remainder is loaded back from the stack frame.
   2442   SDValue Rem = DAG.getLoad(RetVT, dl, LastCALLSEQ_END, FIPtr,
   2443                             MachinePointerInfo(), false, false, 0);
   2444   Results.push_back(CallInfo.first);
   2445   Results.push_back(Rem);
   2446 }
   2447 
   2448 /// ExpandLegalINT_TO_FP - This function is responsible for legalizing a
   2449 /// INT_TO_FP operation of the specified operand when the target requests that
   2450 /// we expand it.  At this point, we know that the result and operand types are
   2451 /// legal for the target.
   2452 SDValue SelectionDAGLegalize::ExpandLegalINT_TO_FP(bool isSigned,
   2453                                                    SDValue Op0,
   2454                                                    EVT DestVT,
   2455                                                    DebugLoc dl) {
   2456   if (Op0.getValueType() == MVT::i32) {
   2457     // simple 32-bit [signed|unsigned] integer to float/double expansion
   2458 
   2459     // Get the stack frame index of a 8 byte buffer.
   2460     SDValue StackSlot = DAG.CreateStackTemporary(MVT::f64);
   2461 
   2462     // word offset constant for Hi/Lo address computation
   2463     SDValue WordOff = DAG.getConstant(sizeof(int), TLI.getPointerTy());
   2464     // set up Hi and Lo (into buffer) address based on endian
   2465     SDValue Hi = StackSlot;
   2466     SDValue Lo = DAG.getNode(ISD::ADD, dl,
   2467                              TLI.getPointerTy(), StackSlot, WordOff);
   2468     if (TLI.isLittleEndian())
   2469       std::swap(Hi, Lo);
   2470 
   2471     // if signed map to unsigned space
   2472     SDValue Op0Mapped;
   2473     if (isSigned) {
   2474       // constant used to invert sign bit (signed to unsigned mapping)
   2475       SDValue SignBit = DAG.getConstant(0x80000000u, MVT::i32);
   2476       Op0Mapped = DAG.getNode(ISD::XOR, dl, MVT::i32, Op0, SignBit);
   2477     } else {
   2478       Op0Mapped = Op0;
   2479     }
   2480     // store the lo of the constructed double - based on integer input
   2481     SDValue Store1 = DAG.getStore(DAG.getEntryNode(), dl,
   2482                                   Op0Mapped, Lo, MachinePointerInfo(),
   2483                                   false, false, 0);
   2484     // initial hi portion of constructed double
   2485     SDValue InitialHi = DAG.getConstant(0x43300000u, MVT::i32);
   2486     // store the hi of the constructed double - biased exponent
   2487     SDValue Store2 = DAG.getStore(Store1, dl, InitialHi, Hi,
   2488                                   MachinePointerInfo(),
   2489                                   false, false, 0);
   2490     // load the constructed double
   2491     SDValue Load = DAG.getLoad(MVT::f64, dl, Store2, StackSlot,
   2492                                MachinePointerInfo(), false, false, 0);
   2493     // FP constant to bias correct the final result
   2494     SDValue Bias = DAG.getConstantFP(isSigned ?
   2495                                      BitsToDouble(0x4330000080000000ULL) :
   2496                                      BitsToDouble(0x4330000000000000ULL),
   2497                                      MVT::f64);
   2498     // subtract the bias
   2499     SDValue Sub = DAG.getNode(ISD::FSUB, dl, MVT::f64, Load, Bias);
   2500     // final result
   2501     SDValue Result;
   2502     // handle final rounding
   2503     if (DestVT == MVT::f64) {
   2504       // do nothing
   2505       Result = Sub;
   2506     } else if (DestVT.bitsLT(MVT::f64)) {
   2507       Result = DAG.getNode(ISD::FP_ROUND, dl, DestVT, Sub,
   2508                            DAG.getIntPtrConstant(0));
   2509     } else if (DestVT.bitsGT(MVT::f64)) {
   2510       Result = DAG.getNode(ISD::FP_EXTEND, dl, DestVT, Sub);
   2511     }
   2512     return Result;
   2513   }
   2514   assert(!isSigned && "Legalize cannot Expand SINT_TO_FP for i64 yet");
   2515   // Code below here assumes !isSigned without checking again.
   2516 
   2517   // Implementation of unsigned i64 to f64 following the algorithm in
   2518   // __floatundidf in compiler_rt. This implementation has the advantage
   2519   // of performing rounding correctly, both in the default rounding mode
   2520   // and in all alternate rounding modes.
   2521   // TODO: Generalize this for use with other types.
   2522   if (Op0.getValueType() == MVT::i64 && DestVT == MVT::f64) {
   2523     SDValue TwoP52 =
   2524       DAG.getConstant(UINT64_C(0x4330000000000000), MVT::i64);
   2525     SDValue TwoP84PlusTwoP52 =
   2526       DAG.getConstantFP(BitsToDouble(UINT64_C(0x4530000000100000)), MVT::f64);
   2527     SDValue TwoP84 =
   2528       DAG.getConstant(UINT64_C(0x4530000000000000), MVT::i64);
   2529 
   2530     SDValue Lo = DAG.getZeroExtendInReg(Op0, dl, MVT::i32);
   2531     SDValue Hi = DAG.getNode(ISD::SRL, dl, MVT::i64, Op0,
   2532                              DAG.getConstant(32, MVT::i64));
   2533     SDValue LoOr = DAG.getNode(ISD::OR, dl, MVT::i64, Lo, TwoP52);
   2534     SDValue HiOr = DAG.getNode(ISD::OR, dl, MVT::i64, Hi, TwoP84);
   2535     SDValue LoFlt = DAG.getNode(ISD::BITCAST, dl, MVT::f64, LoOr);
   2536     SDValue HiFlt = DAG.getNode(ISD::BITCAST, dl, MVT::f64, HiOr);
   2537     SDValue HiSub = DAG.getNode(ISD::FSUB, dl, MVT::f64, HiFlt,
   2538                                 TwoP84PlusTwoP52);
   2539     return DAG.getNode(ISD::FADD, dl, MVT::f64, LoFlt, HiSub);
   2540   }
   2541 
   2542   // Implementation of unsigned i64 to f32.
   2543   // TODO: Generalize this for use with other types.
   2544   if (Op0.getValueType() == MVT::i64 && DestVT == MVT::f32) {
   2545     // For unsigned conversions, convert them to signed conversions using the
   2546     // algorithm from the x86_64 __floatundidf in compiler_rt.
   2547     if (!isSigned) {
   2548       SDValue Fast = DAG.getNode(ISD::SINT_TO_FP, dl, MVT::f32, Op0);
   2549 
   2550       SDValue ShiftConst =
   2551           DAG.getConstant(1, TLI.getShiftAmountTy(Op0.getValueType()));
   2552       SDValue Shr = DAG.getNode(ISD::SRL, dl, MVT::i64, Op0, ShiftConst);
   2553       SDValue AndConst = DAG.getConstant(1, MVT::i64);
   2554       SDValue And = DAG.getNode(ISD::AND, dl, MVT::i64, Op0, AndConst);
   2555       SDValue Or = DAG.getNode(ISD::OR, dl, MVT::i64, And, Shr);
   2556 
   2557       SDValue SignCvt = DAG.getNode(ISD::SINT_TO_FP, dl, MVT::f32, Or);
   2558       SDValue Slow = DAG.getNode(ISD::FADD, dl, MVT::f32, SignCvt, SignCvt);
   2559 
   2560       // TODO: This really should be implemented using a branch rather than a
   2561       // select.  We happen to get lucky and machinesink does the right
   2562       // thing most of the time.  This would be a good candidate for a
   2563       //pseudo-op, or, even better, for whole-function isel.
   2564       SDValue SignBitTest = DAG.getSetCC(dl, TLI.getSetCCResultType(MVT::i64),
   2565         Op0, DAG.getConstant(0, MVT::i64), ISD::SETLT);
   2566       return DAG.getNode(ISD::SELECT, dl, MVT::f32, SignBitTest, Slow, Fast);
   2567     }
   2568 
   2569     // Otherwise, implement the fully general conversion.
   2570 
   2571     SDValue And = DAG.getNode(ISD::AND, dl, MVT::i64, Op0,
   2572          DAG.getConstant(UINT64_C(0xfffffffffffff800), MVT::i64));
   2573     SDValue Or = DAG.getNode(ISD::OR, dl, MVT::i64, And,
   2574          DAG.getConstant(UINT64_C(0x800), MVT::i64));
   2575     SDValue And2 = DAG.getNode(ISD::AND, dl, MVT::i64, Op0,
   2576          DAG.getConstant(UINT64_C(0x7ff), MVT::i64));
   2577     SDValue Ne = DAG.getSetCC(dl, TLI.getSetCCResultType(MVT::i64),
   2578                    And2, DAG.getConstant(UINT64_C(0), MVT::i64), ISD::SETNE);
   2579     SDValue Sel = DAG.getNode(ISD::SELECT, dl, MVT::i64, Ne, Or, Op0);
   2580     SDValue Ge = DAG.getSetCC(dl, TLI.getSetCCResultType(MVT::i64),
   2581                    Op0, DAG.getConstant(UINT64_C(0x0020000000000000), MVT::i64),
   2582                    ISD::SETUGE);
   2583     SDValue Sel2 = DAG.getNode(ISD::SELECT, dl, MVT::i64, Ge, Sel, Op0);
   2584     EVT SHVT = TLI.getShiftAmountTy(Sel2.getValueType());
   2585 
   2586     SDValue Sh = DAG.getNode(ISD::SRL, dl, MVT::i64, Sel2,
   2587                              DAG.getConstant(32, SHVT));
   2588     SDValue Trunc = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, Sh);
   2589     SDValue Fcvt = DAG.getNode(ISD::UINT_TO_FP, dl, MVT::f64, Trunc);
   2590     SDValue TwoP32 =
   2591       DAG.getConstantFP(BitsToDouble(UINT64_C(0x41f0000000000000)), MVT::f64);
   2592     SDValue Fmul = DAG.getNode(ISD::FMUL, dl, MVT::f64, TwoP32, Fcvt);
   2593     SDValue Lo = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, Sel2);
   2594     SDValue Fcvt2 = DAG.getNode(ISD::UINT_TO_FP, dl, MVT::f64, Lo);
   2595     SDValue Fadd = DAG.getNode(ISD::FADD, dl, MVT::f64, Fmul, Fcvt2);
   2596     return DAG.getNode(ISD::FP_ROUND, dl, MVT::f32, Fadd,
   2597                        DAG.getIntPtrConstant(0));
   2598   }
   2599 
   2600   SDValue Tmp1 = DAG.getNode(ISD::SINT_TO_FP, dl, DestVT, Op0);
   2601 
   2602   SDValue SignSet = DAG.getSetCC(dl, TLI.getSetCCResultType(Op0.getValueType()),
   2603                                  Op0, DAG.getConstant(0, Op0.getValueType()),
   2604                                  ISD::SETLT);
   2605   SDValue Zero = DAG.getIntPtrConstant(0), Four = DAG.getIntPtrConstant(4);
   2606   SDValue CstOffset = DAG.getNode(ISD::SELECT, dl, Zero.getValueType(),
   2607                                     SignSet, Four, Zero);
   2608 
   2609   // If the sign bit of the integer is set, the large number will be treated
   2610   // as a negative number.  To counteract this, the dynamic code adds an
   2611   // offset depending on the data type.
   2612   uint64_t FF;
   2613   switch (Op0.getValueType().getSimpleVT().SimpleTy) {
   2614   default: assert(0 && "Unsupported integer type!");
   2615   case MVT::i8 : FF = 0x43800000ULL; break;  // 2^8  (as a float)
   2616   case MVT::i16: FF = 0x47800000ULL; break;  // 2^16 (as a float)
   2617   case MVT::i32: FF = 0x4F800000ULL; break;  // 2^32 (as a float)
   2618   case MVT::i64: FF = 0x5F800000ULL; break;  // 2^64 (as a float)
   2619   }
   2620   if (TLI.isLittleEndian()) FF <<= 32;
   2621   Constant *FudgeFactor = ConstantInt::get(
   2622                                        Type::getInt64Ty(*DAG.getContext()), FF);
   2623 
   2624   SDValue CPIdx = DAG.getConstantPool(FudgeFactor, TLI.getPointerTy());
   2625   unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
   2626   CPIdx = DAG.getNode(ISD::ADD, dl, TLI.getPointerTy(), CPIdx, CstOffset);
   2627   Alignment = std::min(Alignment, 4u);
   2628   SDValue FudgeInReg;
   2629   if (DestVT == MVT::f32)
   2630     FudgeInReg = DAG.getLoad(MVT::f32, dl, DAG.getEntryNode(), CPIdx,
   2631                              MachinePointerInfo::getConstantPool(),
   2632                              false, false, Alignment);
   2633   else {
   2634     FudgeInReg =
   2635       LegalizeOp(DAG.getExtLoad(ISD::EXTLOAD, dl, DestVT,
   2636                                 DAG.getEntryNode(), CPIdx,
   2637                                 MachinePointerInfo::getConstantPool(),
   2638                                 MVT::f32, false, false, Alignment));
   2639   }
   2640 
   2641   return DAG.getNode(ISD::FADD, dl, DestVT, Tmp1, FudgeInReg);
   2642 }
   2643 
   2644 /// PromoteLegalINT_TO_FP - This function is responsible for legalizing a
   2645 /// *INT_TO_FP operation of the specified operand when the target requests that
   2646 /// we promote it.  At this point, we know that the result and operand types are
   2647 /// legal for the target, and that there is a legal UINT_TO_FP or SINT_TO_FP
   2648 /// operation that takes a larger input.
   2649 SDValue SelectionDAGLegalize::PromoteLegalINT_TO_FP(SDValue LegalOp,
   2650                                                     EVT DestVT,
   2651                                                     bool isSigned,
   2652                                                     DebugLoc dl) {
   2653   // First step, figure out the appropriate *INT_TO_FP operation to use.
   2654   EVT NewInTy = LegalOp.getValueType();
   2655 
   2656   unsigned OpToUse = 0;
   2657 
   2658   // Scan for the appropriate larger type to use.
   2659   while (1) {
   2660     NewInTy = (MVT::SimpleValueType)(NewInTy.getSimpleVT().SimpleTy+1);
   2661     assert(NewInTy.isInteger() && "Ran out of possibilities!");
   2662 
   2663     // If the target supports SINT_TO_FP of this type, use it.
   2664     if (TLI.isOperationLegalOrCustom(ISD::SINT_TO_FP, NewInTy)) {
   2665       OpToUse = ISD::SINT_TO_FP;
   2666       break;
   2667     }
   2668     if (isSigned) continue;
   2669 
   2670     // If the target supports UINT_TO_FP of this type, use it.
   2671     if (TLI.isOperationLegalOrCustom(ISD::UINT_TO_FP, NewInTy)) {
   2672       OpToUse = ISD::UINT_TO_FP;
   2673       break;
   2674     }
   2675 
   2676     // Otherwise, try a larger type.
   2677   }
   2678 
   2679   // Okay, we found the operation and type to use.  Zero extend our input to the
   2680   // desired type then run the operation on it.
   2681   return DAG.getNode(OpToUse, dl, DestVT,
   2682                      DAG.getNode(isSigned ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND,
   2683                                  dl, NewInTy, LegalOp));
   2684 }
   2685 
   2686 /// PromoteLegalFP_TO_INT - This function is responsible for legalizing a
   2687 /// FP_TO_*INT operation of the specified operand when the target requests that
   2688 /// we promote it.  At this point, we know that the result and operand types are
   2689 /// legal for the target, and that there is a legal FP_TO_UINT or FP_TO_SINT
   2690 /// operation that returns a larger result.
   2691 SDValue SelectionDAGLegalize::PromoteLegalFP_TO_INT(SDValue LegalOp,
   2692                                                     EVT DestVT,
   2693                                                     bool isSigned,
   2694                                                     DebugLoc dl) {
   2695   // First step, figure out the appropriate FP_TO*INT operation to use.
   2696   EVT NewOutTy = DestVT;
   2697 
   2698   unsigned OpToUse = 0;
   2699 
   2700   // Scan for the appropriate larger type to use.
   2701   while (1) {
   2702     NewOutTy = (MVT::SimpleValueType)(NewOutTy.getSimpleVT().SimpleTy+1);
   2703     assert(NewOutTy.isInteger() && "Ran out of possibilities!");
   2704 
   2705     if (TLI.isOperationLegalOrCustom(ISD::FP_TO_SINT, NewOutTy)) {
   2706       OpToUse = ISD::FP_TO_SINT;
   2707       break;
   2708     }
   2709 
   2710     if (TLI.isOperationLegalOrCustom(ISD::FP_TO_UINT, NewOutTy)) {
   2711       OpToUse = ISD::FP_TO_UINT;
   2712       break;
   2713     }
   2714 
   2715     // Otherwise, try a larger type.
   2716   }
   2717 
   2718 
   2719   // Okay, we found the operation and type to use.
   2720   SDValue Operation = DAG.getNode(OpToUse, dl, NewOutTy, LegalOp);
   2721 
   2722   // Truncate the result of the extended FP_TO_*INT operation to the desired
   2723   // size.
   2724   return DAG.getNode(ISD::TRUNCATE, dl, DestVT, Operation);
   2725 }
   2726 
   2727 /// ExpandBSWAP - Open code the operations for BSWAP of the specified operation.
   2728 ///
   2729 SDValue SelectionDAGLegalize::ExpandBSWAP(SDValue Op, DebugLoc dl) {
   2730   EVT VT = Op.getValueType();
   2731   EVT SHVT = TLI.getShiftAmountTy(VT);
   2732   SDValue Tmp1, Tmp2, Tmp3, Tmp4, Tmp5, Tmp6, Tmp7, Tmp8;
   2733   switch (VT.getSimpleVT().SimpleTy) {
   2734   default: assert(0 && "Unhandled Expand type in BSWAP!");
   2735   case MVT::i16:
   2736     Tmp2 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, SHVT));
   2737     Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, SHVT));
   2738     return DAG.getNode(ISD::OR, dl, VT, Tmp1, Tmp2);
   2739   case MVT::i32:
   2740     Tmp4 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(24, SHVT));
   2741     Tmp3 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, SHVT));
   2742     Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, SHVT));
   2743     Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(24, SHVT));
   2744     Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp3, DAG.getConstant(0xFF0000, VT));
   2745     Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2, DAG.getConstant(0xFF00, VT));
   2746     Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp3);
   2747     Tmp2 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp1);
   2748     return DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp2);
   2749   case MVT::i64:
   2750     Tmp8 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(56, SHVT));
   2751     Tmp7 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(40, SHVT));
   2752     Tmp6 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(24, SHVT));
   2753     Tmp5 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, SHVT));
   2754     Tmp4 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, SHVT));
   2755     Tmp3 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(24, SHVT));
   2756     Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(40, SHVT));
   2757     Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(56, SHVT));
   2758     Tmp7 = DAG.getNode(ISD::AND, dl, VT, Tmp7, DAG.getConstant(255ULL<<48, VT));
   2759     Tmp6 = DAG.getNode(ISD::AND, dl, VT, Tmp6, DAG.getConstant(255ULL<<40, VT));
   2760     Tmp5 = DAG.getNode(ISD::AND, dl, VT, Tmp5, DAG.getConstant(255ULL<<32, VT));
   2761     Tmp4 = DAG.getNode(ISD::AND, dl, VT, Tmp4, DAG.getConstant(255ULL<<24, VT));
   2762     Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp3, DAG.getConstant(255ULL<<16, VT));
   2763     Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2, DAG.getConstant(255ULL<<8 , VT));
   2764     Tmp8 = DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp7);
   2765     Tmp6 = DAG.getNode(ISD::OR, dl, VT, Tmp6, Tmp5);
   2766     Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp3);
   2767     Tmp2 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp1);
   2768     Tmp8 = DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp6);
   2769     Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp2);
   2770     return DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp4);
   2771   }
   2772 }
   2773 
   2774 /// SplatByte - Distribute ByteVal over NumBits bits.
   2775 // FIXME: Move this helper to a common place.
   2776 static APInt SplatByte(unsigned NumBits, uint8_t ByteVal) {
   2777   APInt Val = APInt(NumBits, ByteVal);
   2778   unsigned Shift = 8;
   2779   for (unsigned i = NumBits; i > 8; i >>= 1) {
   2780     Val = (Val << Shift) | Val;
   2781     Shift <<= 1;
   2782   }
   2783   return Val;
   2784 }
   2785 
   2786 /// ExpandBitCount - Expand the specified bitcount instruction into operations.
   2787 ///
   2788 SDValue SelectionDAGLegalize::ExpandBitCount(unsigned Opc, SDValue Op,
   2789                                              DebugLoc dl) {
   2790   switch (Opc) {
   2791   default: assert(0 && "Cannot expand this yet!");
   2792   case ISD::CTPOP: {
   2793     EVT VT = Op.getValueType();
   2794     EVT ShVT = TLI.getShiftAmountTy(VT);
   2795     unsigned Len = VT.getSizeInBits();
   2796 
   2797     assert(VT.isInteger() && Len <= 128 && Len % 8 == 0 &&
   2798            "CTPOP not implemented for this type.");
   2799 
   2800     // This is the "best" algorithm from
   2801     // http://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetParallel
   2802 
   2803     SDValue Mask55 = DAG.getConstant(SplatByte(Len, 0x55), VT);
   2804     SDValue Mask33 = DAG.getConstant(SplatByte(Len, 0x33), VT);
   2805     SDValue Mask0F = DAG.getConstant(SplatByte(Len, 0x0F), VT);
   2806     SDValue Mask01 = DAG.getConstant(SplatByte(Len, 0x01), VT);
   2807 
   2808     // v = v - ((v >> 1) & 0x55555555...)
   2809     Op = DAG.getNode(ISD::SUB, dl, VT, Op,
   2810                      DAG.getNode(ISD::AND, dl, VT,
   2811                                  DAG.getNode(ISD::SRL, dl, VT, Op,
   2812                                              DAG.getConstant(1, ShVT)),
   2813                                  Mask55));
   2814     // v = (v & 0x33333333...) + ((v >> 2) & 0x33333333...)
   2815     Op = DAG.getNode(ISD::ADD, dl, VT,
   2816                      DAG.getNode(ISD::AND, dl, VT, Op, Mask33),
   2817                      DAG.getNode(ISD::AND, dl, VT,
   2818                                  DAG.getNode(ISD::SRL, dl, VT, Op,
   2819                                              DAG.getConstant(2, ShVT)),
   2820                                  Mask33));
   2821     // v = (v + (v >> 4)) & 0x0F0F0F0F...
   2822     Op = DAG.getNode(ISD::AND, dl, VT,
   2823                      DAG.getNode(ISD::ADD, dl, VT, Op,
   2824                                  DAG.getNode(ISD::SRL, dl, VT, Op,
   2825                                              DAG.getConstant(4, ShVT))),
   2826                      Mask0F);
   2827     // v = (v * 0x01010101...) >> (Len - 8)
   2828     Op = DAG.getNode(ISD::SRL, dl, VT,
   2829                      DAG.getNode(ISD::MUL, dl, VT, Op, Mask01),
   2830                      DAG.getConstant(Len - 8, ShVT));
   2831 
   2832     return Op;
   2833   }
   2834   case ISD::CTLZ: {
   2835     // for now, we do this:
   2836     // x = x | (x >> 1);
   2837     // x = x | (x >> 2);
   2838     // ...
   2839     // x = x | (x >>16);
   2840     // x = x | (x >>32); // for 64-bit input
   2841     // return popcount(~x);
   2842     //
   2843     // but see also: http://www.hackersdelight.org/HDcode/nlz.cc
   2844     EVT VT = Op.getValueType();
   2845     EVT ShVT = TLI.getShiftAmountTy(VT);
   2846     unsigned len = VT.getSizeInBits();
   2847     for (unsigned i = 0; (1U << i) <= (len / 2); ++i) {
   2848       SDValue Tmp3 = DAG.getConstant(1ULL << i, ShVT);
   2849       Op = DAG.getNode(ISD::OR, dl, VT, Op,
   2850                        DAG.getNode(ISD::SRL, dl, VT, Op, Tmp3));
   2851     }
   2852     Op = DAG.getNOT(dl, Op, VT);
   2853     return DAG.getNode(ISD::CTPOP, dl, VT, Op);
   2854   }
   2855   case ISD::CTTZ: {
   2856     // for now, we use: { return popcount(~x & (x - 1)); }
   2857     // unless the target has ctlz but not ctpop, in which case we use:
   2858     // { return 32 - nlz(~x & (x-1)); }
   2859     // see also http://www.hackersdelight.org/HDcode/ntz.cc
   2860     EVT VT = Op.getValueType();
   2861     SDValue Tmp3 = DAG.getNode(ISD::AND, dl, VT,
   2862                                DAG.getNOT(dl, Op, VT),
   2863                                DAG.getNode(ISD::SUB, dl, VT, Op,
   2864                                            DAG.getConstant(1, VT)));
   2865     // If ISD::CTLZ is legal and CTPOP isn't, then do that instead.
   2866     if (!TLI.isOperationLegalOrCustom(ISD::CTPOP, VT) &&
   2867         TLI.isOperationLegalOrCustom(ISD::CTLZ, VT))
   2868       return DAG.getNode(ISD::SUB, dl, VT,
   2869                          DAG.getConstant(VT.getSizeInBits(), VT),
   2870                          DAG.getNode(ISD::CTLZ, dl, VT, Tmp3));
   2871     return DAG.getNode(ISD::CTPOP, dl, VT, Tmp3);
   2872   }
   2873   }
   2874 }
   2875 
   2876 std::pair <SDValue, SDValue> SelectionDAGLegalize::ExpandAtomic(SDNode *Node) {
   2877   unsigned Opc = Node->getOpcode();
   2878   MVT VT = cast<AtomicSDNode>(Node)->getMemoryVT().getSimpleVT();
   2879   RTLIB::Libcall LC;
   2880 
   2881   switch (Opc) {
   2882   default:
   2883     llvm_unreachable("Unhandled atomic intrinsic Expand!");
   2884     break;
   2885   case ISD::ATOMIC_SWAP:
   2886     switch (VT.SimpleTy) {
   2887     default: llvm_unreachable("Unexpected value type for atomic!");
   2888     case MVT::i8:  LC = RTLIB::SYNC_LOCK_TEST_AND_SET_1; break;
   2889     case MVT::i16: LC = RTLIB::SYNC_LOCK_TEST_AND_SET_2; break;
   2890     case MVT::i32: LC = RTLIB::SYNC_LOCK_TEST_AND_SET_4; break;
   2891     case MVT::i64: LC = RTLIB::SYNC_LOCK_TEST_AND_SET_8; break;
   2892     }
   2893     break;
   2894   case ISD::ATOMIC_CMP_SWAP:
   2895     switch (VT.SimpleTy) {
   2896     default: llvm_unreachable("Unexpected value type for atomic!");
   2897     case MVT::i8:  LC = RTLIB::SYNC_VAL_COMPARE_AND_SWAP_1; break;
   2898     case MVT::i16: LC = RTLIB::SYNC_VAL_COMPARE_AND_SWAP_2; break;
   2899     case MVT::i32: LC = RTLIB::SYNC_VAL_COMPARE_AND_SWAP_4; break;
   2900     case MVT::i64: LC = RTLIB::SYNC_VAL_COMPARE_AND_SWAP_8; break;
   2901     }
   2902     break;
   2903   case ISD::ATOMIC_LOAD_ADD:
   2904     switch (VT.SimpleTy) {
   2905     default: llvm_unreachable("Unexpected value type for atomic!");
   2906     case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_ADD_1; break;
   2907     case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_ADD_2; break;
   2908     case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_ADD_4; break;
   2909     case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_ADD_8; break;
   2910     }
   2911     break;
   2912   case ISD::ATOMIC_LOAD_SUB:
   2913     switch (VT.SimpleTy) {
   2914     default: llvm_unreachable("Unexpected value type for atomic!");
   2915     case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_SUB_1; break;
   2916     case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_SUB_2; break;
   2917     case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_SUB_4; break;
   2918     case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_SUB_8; break;
   2919     }
   2920     break;
   2921   case ISD::ATOMIC_LOAD_AND:
   2922     switch (VT.SimpleTy) {
   2923     default: llvm_unreachable("Unexpected value type for atomic!");
   2924     case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_AND_1; break;
   2925     case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_AND_2; break;
   2926     case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_AND_4; break;
   2927     case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_AND_8; break;
   2928     }
   2929     break;
   2930   case ISD::ATOMIC_LOAD_OR:
   2931     switch (VT.SimpleTy) {
   2932     default: llvm_unreachable("Unexpected value type for atomic!");
   2933     case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_OR_1; break;
   2934     case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_OR_2; break;
   2935     case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_OR_4; break;
   2936     case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_OR_8; break;
   2937     }
   2938     break;
   2939   case ISD::ATOMIC_LOAD_XOR:
   2940     switch (VT.SimpleTy) {
   2941     default: llvm_unreachable("Unexpected value type for atomic!");
   2942     case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_XOR_1; break;
   2943     case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_XOR_2; break;
   2944     case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_XOR_4; break;
   2945     case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_XOR_8; break;
   2946     }
   2947     break;
   2948   case ISD::ATOMIC_LOAD_NAND:
   2949     switch (VT.SimpleTy) {
   2950     default: llvm_unreachable("Unexpected value type for atomic!");
   2951     case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_NAND_1; break;
   2952     case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_NAND_2; break;
   2953     case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_NAND_4; break;
   2954     case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_NAND_8; break;
   2955     }
   2956     break;
   2957   }
   2958 
   2959   return ExpandChainLibCall(LC, Node, false);
   2960 }
   2961 
   2962 void SelectionDAGLegalize::ExpandNode(SDNode *Node,
   2963                                       SmallVectorImpl<SDValue> &Results) {
   2964   DebugLoc dl = Node->getDebugLoc();
   2965   SDValue Tmp1, Tmp2, Tmp3, Tmp4;
   2966   switch (Node->getOpcode()) {
   2967   case ISD::CTPOP:
   2968   case ISD::CTLZ:
   2969   case ISD::CTTZ:
   2970     Tmp1 = ExpandBitCount(Node->getOpcode(), Node->getOperand(0), dl);
   2971     Results.push_back(Tmp1);
   2972     break;
   2973   case ISD::BSWAP:
   2974     Results.push_back(ExpandBSWAP(Node->getOperand(0), dl));
   2975     break;
   2976   case ISD::FRAMEADDR:
   2977   case ISD::RETURNADDR:
   2978   case ISD::FRAME_TO_ARGS_OFFSET:
   2979     Results.push_back(DAG.getConstant(0, Node->getValueType(0)));
   2980     break;
   2981   case ISD::FLT_ROUNDS_:
   2982     Results.push_back(DAG.getConstant(1, Node->getValueType(0)));
   2983     break;
   2984   case ISD::EH_RETURN:
   2985   case ISD::EH_LABEL:
   2986   case ISD::PREFETCH:
   2987   case ISD::VAEND:
   2988   case ISD::EH_SJLJ_LONGJMP:
   2989   case ISD::EH_SJLJ_DISPATCHSETUP:
   2990     // If the target didn't expand these, there's nothing to do, so just
   2991     // preserve the chain and be done.
   2992     Results.push_back(Node->getOperand(0));
   2993     break;
   2994   case ISD::EH_SJLJ_SETJMP:
   2995     // If the target didn't expand this, just return 'zero' and preserve the
   2996     // chain.
   2997     Results.push_back(DAG.getConstant(0, MVT::i32));
   2998     Results.push_back(Node->getOperand(0));
   2999     break;
   3000   case ISD::ATOMIC_FENCE:
   3001   case ISD::MEMBARRIER: {
   3002     // If the target didn't lower this, lower it to '__sync_synchronize()' call
   3003     // FIXME: handle "fence singlethread" more efficiently.
   3004     TargetLowering::ArgListTy Args;
   3005     std::pair<SDValue, SDValue> CallResult =
   3006       TLI.LowerCallTo(Node->getOperand(0), Type::getVoidTy(*DAG.getContext()),
   3007                       false, false, false, false, 0, CallingConv::C,
   3008                       /*isTailCall=*/false,
   3009                       /*isReturnValueUsed=*/true,
   3010                       DAG.getExternalSymbol("__sync_synchronize",
   3011                                             TLI.getPointerTy()),
   3012                       Args, DAG, dl);
   3013     Results.push_back(CallResult.second);
   3014     break;
   3015   }
   3016   case ISD::ATOMIC_LOAD: {
   3017     // There is no libcall for atomic load; fake it with ATOMIC_CMP_SWAP.
   3018     SDValue Zero = DAG.getConstant(0, Node->getValueType(0));
   3019     SDValue Swap = DAG.getAtomic(ISD::ATOMIC_CMP_SWAP, dl,
   3020                                  cast<AtomicSDNode>(Node)->getMemoryVT(),
   3021                                  Node->getOperand(0),
   3022                                  Node->getOperand(1), Zero, Zero,
   3023                                  cast<AtomicSDNode>(Node)->getMemOperand(),
   3024                                  cast<AtomicSDNode>(Node)->getOrdering(),
   3025                                  cast<AtomicSDNode>(Node)->getSynchScope());
   3026     Results.push_back(Swap.getValue(0));
   3027     Results.push_back(Swap.getValue(1));
   3028     break;
   3029   }
   3030   case ISD::ATOMIC_STORE: {
   3031     // There is no libcall for atomic store; fake it with ATOMIC_SWAP.
   3032     SDValue Swap = DAG.getAtomic(ISD::ATOMIC_SWAP, dl,
   3033                                  cast<AtomicSDNode>(Node)->getMemoryVT(),
   3034                                  Node->getOperand(0),
   3035                                  Node->getOperand(1), Node->getOperand(2),
   3036                                  cast<AtomicSDNode>(Node)->getMemOperand(),
   3037                                  cast<AtomicSDNode>(Node)->getOrdering(),
   3038                                  cast<AtomicSDNode>(Node)->getSynchScope());
   3039     Results.push_back(Swap.getValue(1));
   3040     break;
   3041   }
   3042   // By default, atomic intrinsics are marked Legal and lowered. Targets
   3043   // which don't support them directly, however, may want libcalls, in which
   3044   // case they mark them Expand, and we get here.
   3045   case ISD::ATOMIC_SWAP:
   3046   case ISD::ATOMIC_LOAD_ADD:
   3047   case ISD::ATOMIC_LOAD_SUB:
   3048   case ISD::ATOMIC_LOAD_AND:
   3049   case ISD::ATOMIC_LOAD_OR:
   3050   case ISD::ATOMIC_LOAD_XOR:
   3051   case ISD::ATOMIC_LOAD_NAND:
   3052   case ISD::ATOMIC_LOAD_MIN:
   3053   case ISD::ATOMIC_LOAD_MAX:
   3054   case ISD::ATOMIC_LOAD_UMIN:
   3055   case ISD::ATOMIC_LOAD_UMAX:
   3056   case ISD::ATOMIC_CMP_SWAP: {
   3057     std::pair<SDValue, SDValue> Tmp = ExpandAtomic(Node);
   3058     Results.push_back(Tmp.first);
   3059     Results.push_back(Tmp.second);
   3060     break;
   3061   }
   3062   case ISD::DYNAMIC_STACKALLOC:
   3063     ExpandDYNAMIC_STACKALLOC(Node, Results);
   3064     break;
   3065   case ISD::MERGE_VALUES:
   3066     for (unsigned i = 0; i < Node->getNumValues(); i++)
   3067       Results.push_back(Node->getOperand(i));
   3068     break;
   3069   case ISD::UNDEF: {
   3070     EVT VT = Node->getValueType(0);
   3071     if (VT.isInteger())
   3072       Results.push_back(DAG.getConstant(0, VT));
   3073     else {
   3074       assert(VT.isFloatingPoint() && "Unknown value type!");
   3075       Results.push_back(DAG.getConstantFP(0, VT));
   3076     }
   3077     break;
   3078   }
   3079   case ISD::TRAP: {
   3080     // If this operation is not supported, lower it to 'abort()' call
   3081     TargetLowering::ArgListTy Args;
   3082     std::pair<SDValue, SDValue> CallResult =
   3083       TLI.LowerCallTo(Node->getOperand(0), Type::getVoidTy(*DAG.getContext()),
   3084                       false, false, false, false, 0, CallingConv::C,
   3085                       /*isTailCall=*/false,
   3086                       /*isReturnValueUsed=*/true,
   3087                       DAG.getExternalSymbol("abort", TLI.getPointerTy()),
   3088                       Args, DAG, dl);
   3089     Results.push_back(CallResult.second);
   3090     break;
   3091   }
   3092   case ISD::FP_ROUND:
   3093   case ISD::BITCAST:
   3094     Tmp1 = EmitStackConvert(Node->getOperand(0), Node->getValueType(0),
   3095                             Node->getValueType(0), dl);
   3096     Results.push_back(Tmp1);
   3097     break;
   3098   case ISD::FP_EXTEND:
   3099     Tmp1 = EmitStackConvert(Node->getOperand(0),
   3100                             Node->getOperand(0).getValueType(),
   3101                             Node->getValueType(0), dl);
   3102     Results.push_back(Tmp1);
   3103     break;
   3104   case ISD::SIGN_EXTEND_INREG: {
   3105     // NOTE: we could fall back on load/store here too for targets without
   3106     // SAR.  However, it is doubtful that any exist.
   3107     EVT ExtraVT = cast<VTSDNode>(Node->getOperand(1))->getVT();
   3108     EVT VT = Node->getValueType(0);
   3109     EVT ShiftAmountTy = TLI.getShiftAmountTy(VT);
   3110     if (VT.isVector())
   3111       ShiftAmountTy = VT;
   3112     unsigned BitsDiff = VT.getScalarType().getSizeInBits() -
   3113                         ExtraVT.getScalarType().getSizeInBits();
   3114     SDValue ShiftCst = DAG.getConstant(BitsDiff, ShiftAmountTy);
   3115     Tmp1 = DAG.getNode(ISD::SHL, dl, Node->getValueType(0),
   3116                        Node->getOperand(0), ShiftCst);
   3117     Tmp1 = DAG.getNode(ISD::SRA, dl, Node->getValueType(0), Tmp1, ShiftCst);
   3118     Results.push_back(Tmp1);
   3119     break;
   3120   }
   3121   case ISD::FP_ROUND_INREG: {
   3122     // The only way we can lower this is to turn it into a TRUNCSTORE,
   3123     // EXTLOAD pair, targeting a temporary location (a stack slot).
   3124 
   3125     // NOTE: there is a choice here between constantly creating new stack
   3126     // slots and always reusing the same one.  We currently always create
   3127     // new ones, as reuse may inhibit scheduling.
   3128     EVT ExtraVT = cast<VTSDNode>(Node->getOperand(1))->getVT();
   3129     Tmp1 = EmitStackConvert(Node->getOperand(0), ExtraVT,
   3130                             Node->getValueType(0), dl);
   3131     Results.push_back(Tmp1);
   3132     break;
   3133   }
   3134   case ISD::SINT_TO_FP:
   3135   case ISD::UINT_TO_FP:
   3136     Tmp1 = ExpandLegalINT_TO_FP(Node->getOpcode() == ISD::SINT_TO_FP,
   3137                                 Node->getOperand(0), Node->getValueType(0), dl);
   3138     Results.push_back(Tmp1);
   3139     break;
   3140   case ISD::FP_TO_UINT: {
   3141     SDValue True, False;
   3142     EVT VT =  Node->getOperand(0).getValueType();
   3143     EVT NVT = Node->getValueType(0);
   3144     APFloat apf(APInt::getNullValue(VT.getSizeInBits()));
   3145     APInt x = APInt::getSignBit(NVT.getSizeInBits());
   3146     (void)apf.convertFromAPInt(x, false, APFloat::rmNearestTiesToEven);
   3147     Tmp1 = DAG.getConstantFP(apf, VT);
   3148     Tmp2 = DAG.getSetCC(dl, TLI.getSetCCResultType(VT),
   3149                         Node->getOperand(0),
   3150                         Tmp1, ISD::SETLT);
   3151     True = DAG.getNode(ISD::FP_TO_SINT, dl, NVT, Node->getOperand(0));
   3152     False = DAG.getNode(ISD::FP_TO_SINT, dl, NVT,
   3153                         DAG.getNode(ISD::FSUB, dl, VT,
   3154                                     Node->getOperand(0), Tmp1));
   3155     False = DAG.getNode(ISD::XOR, dl, NVT, False,
   3156                         DAG.getConstant(x, NVT));
   3157     Tmp1 = DAG.getNode(ISD::SELECT, dl, NVT, Tmp2, True, False);
   3158     Results.push_back(Tmp1);
   3159     break;
   3160   }
   3161   case ISD::VAARG: {
   3162     const Value *V = cast<SrcValueSDNode>(Node->getOperand(2))->getValue();
   3163     EVT VT = Node->getValueType(0);
   3164     Tmp1 = Node->getOperand(0);
   3165     Tmp2 = Node->getOperand(1);
   3166     unsigned Align = Node->getConstantOperandVal(3);
   3167 
   3168     SDValue VAListLoad = DAG.getLoad(TLI.getPointerTy(), dl, Tmp1, Tmp2,
   3169                                      MachinePointerInfo(V), false, false, 0);
   3170     SDValue VAList = VAListLoad;
   3171 
   3172     if (Align > TLI.getMinStackArgumentAlignment()) {
   3173       assert(((Align & (Align-1)) == 0) && "Expected Align to be a power of 2");
   3174 
   3175       VAList = DAG.getNode(ISD::ADD, dl, TLI.getPointerTy(), VAList,
   3176                            DAG.getConstant(Align - 1,
   3177                                            TLI.getPointerTy()));
   3178 
   3179       VAList = DAG.getNode(ISD::AND, dl, TLI.getPointerTy(), VAList,
   3180                            DAG.getConstant(-(int64_t)Align,
   3181                                            TLI.getPointerTy()));
   3182     }
   3183 
   3184     // Increment the pointer, VAList, to the next vaarg
   3185     Tmp3 = DAG.getNode(ISD::ADD, dl, TLI.getPointerTy(), VAList,
   3186                        DAG.getConstant(TLI.getTargetData()->
   3187                           getTypeAllocSize(VT.getTypeForEVT(*DAG.getContext())),
   3188                                        TLI.getPointerTy()));
   3189     // Store the incremented VAList to the legalized pointer
   3190     Tmp3 = DAG.getStore(VAListLoad.getValue(1), dl, Tmp3, Tmp2,
   3191                         MachinePointerInfo(V), false, false, 0);
   3192     // Load the actual argument out of the pointer VAList
   3193     Results.push_back(DAG.getLoad(VT, dl, Tmp3, VAList, MachinePointerInfo(),
   3194                                   false, false, 0));
   3195     Results.push_back(Results[0].getValue(1));
   3196     break;
   3197   }
   3198   case ISD::VACOPY: {
   3199     // This defaults to loading a pointer from the input and storing it to the
   3200     // output, returning the chain.
   3201     const Value *VD = cast<SrcValueSDNode>(Node->getOperand(3))->getValue();
   3202     const Value *VS = cast<SrcValueSDNode>(Node->getOperand(4))->getValue();
   3203     Tmp1 = DAG.getLoad(TLI.getPointerTy(), dl, Node->getOperand(0),
   3204                        Node->getOperand(2), MachinePointerInfo(VS),
   3205                        false, false, 0);
   3206     Tmp1 = DAG.getStore(Tmp1.getValue(1), dl, Tmp1, Node->getOperand(1),
   3207                         MachinePointerInfo(VD), false, false, 0);
   3208     Results.push_back(Tmp1);
   3209     break;
   3210   }
   3211   case ISD::EXTRACT_VECTOR_ELT:
   3212     if (Node->getOperand(0).getValueType().getVectorNumElements() == 1)
   3213       // This must be an access of the only element.  Return it.
   3214       Tmp1 = DAG.getNode(ISD::BITCAST, dl, Node->getValueType(0),
   3215                          Node->getOperand(0));
   3216     else
   3217       Tmp1 = ExpandExtractFromVectorThroughStack(SDValue(Node, 0));
   3218     Results.push_back(Tmp1);
   3219     break;
   3220   case ISD::EXTRACT_SUBVECTOR:
   3221     Results.push_back(ExpandExtractFromVectorThroughStack(SDValue(Node, 0)));
   3222     break;
   3223   case ISD::INSERT_SUBVECTOR:
   3224     Results.push_back(ExpandInsertToVectorThroughStack(SDValue(Node, 0)));
   3225     break;
   3226   case ISD::CONCAT_VECTORS: {
   3227     Results.push_back(ExpandVectorBuildThroughStack(Node));
   3228     break;
   3229   }
   3230   case ISD::SCALAR_TO_VECTOR:
   3231     Results.push_back(ExpandSCALAR_TO_VECTOR(Node));
   3232     break;
   3233   case ISD::INSERT_VECTOR_ELT:
   3234     Results.push_back(ExpandINSERT_VECTOR_ELT(Node->getOperand(0),
   3235                                               Node->getOperand(1),
   3236                                               Node->getOperand(2), dl));
   3237     break;
   3238   case ISD::VECTOR_SHUFFLE: {
   3239     SmallVector<int, 8> Mask;
   3240     cast<ShuffleVectorSDNode>(Node)->getMask(Mask);
   3241 
   3242     EVT VT = Node->getValueType(0);
   3243     EVT EltVT = VT.getVectorElementType();
   3244     if (!TLI.isTypeLegal(EltVT))
   3245       EltVT = TLI.getTypeToTransformTo(*DAG.getContext(), EltVT);
   3246     unsigned NumElems = VT.getVectorNumElements();
   3247     SmallVector<SDValue, 8> Ops;
   3248     for (unsigned i = 0; i != NumElems; ++i) {
   3249       if (Mask[i] < 0) {
   3250         Ops.push_back(DAG.getUNDEF(EltVT));
   3251         continue;
   3252       }
   3253       unsigned Idx = Mask[i];
   3254       if (Idx < NumElems)
   3255         Ops.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, EltVT,
   3256                                   Node->getOperand(0),
   3257                                   DAG.getIntPtrConstant(Idx)));
   3258       else
   3259         Ops.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, EltVT,
   3260                                   Node->getOperand(1),
   3261                                   DAG.getIntPtrConstant(Idx - NumElems)));
   3262     }
   3263     Tmp1 = DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], Ops.size());
   3264     Results.push_back(Tmp1);
   3265     break;
   3266   }
   3267   case ISD::EXTRACT_ELEMENT: {
   3268     EVT OpTy = Node->getOperand(0).getValueType();
   3269     if (cast<ConstantSDNode>(Node->getOperand(1))->getZExtValue()) {
   3270       // 1 -> Hi
   3271       Tmp1 = DAG.getNode(ISD::SRL, dl, OpTy, Node->getOperand(0),
   3272                          DAG.getConstant(OpTy.getSizeInBits()/2,
   3273                     TLI.getShiftAmountTy(Node->getOperand(0).getValueType())));
   3274       Tmp1 = DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0), Tmp1);
   3275     } else {
   3276       // 0 -> Lo
   3277       Tmp1 = DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0),
   3278                          Node->getOperand(0));
   3279     }
   3280     Results.push_back(Tmp1);
   3281     break;
   3282   }
   3283   case ISD::STACKSAVE:
   3284     // Expand to CopyFromReg if the target set
   3285     // StackPointerRegisterToSaveRestore.
   3286     if (unsigned SP = TLI.getStackPointerRegisterToSaveRestore()) {
   3287       Results.push_back(DAG.getCopyFromReg(Node->getOperand(0), dl, SP,
   3288                                            Node->getValueType(0)));
   3289       Results.push_back(Results[0].getValue(1));
   3290     } else {
   3291       Results.push_back(DAG.getUNDEF(Node->getValueType(0)));
   3292       Results.push_back(Node->getOperand(0));
   3293     }
   3294     break;
   3295   case ISD::STACKRESTORE:
   3296     // Expand to CopyToReg if the target set
   3297     // StackPointerRegisterToSaveRestore.
   3298     if (unsigned SP = TLI.getStackPointerRegisterToSaveRestore()) {
   3299       Results.push_back(DAG.getCopyToReg(Node->getOperand(0), dl, SP,
   3300                                          Node->getOperand(1)));
   3301     } else {
   3302       Results.push_back(Node->getOperand(0));
   3303     }
   3304     break;
   3305   case ISD::FCOPYSIGN:
   3306     Results.push_back(ExpandFCOPYSIGN(Node));
   3307     break;
   3308   case ISD::FNEG:
   3309     // Expand Y = FNEG(X) ->  Y = SUB -0.0, X
   3310     Tmp1 = DAG.getConstantFP(-0.0, Node->getValueType(0));
   3311     Tmp1 = DAG.getNode(ISD::FSUB, dl, Node->getValueType(0), Tmp1,
   3312                        Node->getOperand(0));
   3313     Results.push_back(Tmp1);
   3314     break;
   3315   case ISD::FABS: {
   3316     // Expand Y = FABS(X) -> Y = (X >u 0.0) ? X : fneg(X).
   3317     EVT VT = Node->getValueType(0);
   3318     Tmp1 = Node->getOperand(0);
   3319     Tmp2 = DAG.getConstantFP(0.0, VT);
   3320     Tmp2 = DAG.getSetCC(dl, TLI.getSetCCResultType(Tmp1.getValueType()),
   3321                         Tmp1, Tmp2, ISD::SETUGT);
   3322     Tmp3 = DAG.getNode(ISD::FNEG, dl, VT, Tmp1);
   3323     Tmp1 = DAG.getNode(ISD::SELECT, dl, VT, Tmp2, Tmp1, Tmp3);
   3324     Results.push_back(Tmp1);
   3325     break;
   3326   }
   3327   case ISD::FSQRT:
   3328     Results.push_back(ExpandFPLibCall(Node, RTLIB::SQRT_F32, RTLIB::SQRT_F64,
   3329                                       RTLIB::SQRT_F80, RTLIB::SQRT_PPCF128));
   3330     break;
   3331   case ISD::FSIN:
   3332     Results.push_back(ExpandFPLibCall(Node, RTLIB::SIN_F32, RTLIB::SIN_F64,
   3333                                       RTLIB::SIN_F80, RTLIB::SIN_PPCF128));
   3334     break;
   3335   case ISD::FCOS:
   3336     Results.push_back(ExpandFPLibCall(Node, RTLIB::COS_F32, RTLIB::COS_F64,
   3337                                       RTLIB::COS_F80, RTLIB::COS_PPCF128));
   3338     break;
   3339   case ISD::FLOG:
   3340     Results.push_back(ExpandFPLibCall(Node, RTLIB::LOG_F32, RTLIB::LOG_F64,
   3341                                       RTLIB::LOG_F80, RTLIB::LOG_PPCF128));
   3342     break;
   3343   case ISD::FLOG2:
   3344     Results.push_back(ExpandFPLibCall(Node, RTLIB::LOG2_F32, RTLIB::LOG2_F64,
   3345                                       RTLIB::LOG2_F80, RTLIB::LOG2_PPCF128));
   3346     break;
   3347   case ISD::FLOG10:
   3348     Results.push_back(ExpandFPLibCall(Node, RTLIB::LOG10_F32, RTLIB::LOG10_F64,
   3349                                       RTLIB::LOG10_F80, RTLIB::LOG10_PPCF128));
   3350     break;
   3351   case ISD::FEXP:
   3352     Results.push_back(ExpandFPLibCall(Node, RTLIB::EXP_F32, RTLIB::EXP_F64,
   3353                                       RTLIB::EXP_F80, RTLIB::EXP_PPCF128));
   3354     break;
   3355   case ISD::FEXP2:
   3356     Results.push_back(ExpandFPLibCall(Node, RTLIB::EXP2_F32, RTLIB::EXP2_F64,
   3357                                       RTLIB::EXP2_F80, RTLIB::EXP2_PPCF128));
   3358     break;
   3359   case ISD::FTRUNC:
   3360     Results.push_back(ExpandFPLibCall(Node, RTLIB::TRUNC_F32, RTLIB::TRUNC_F64,
   3361                                       RTLIB::TRUNC_F80, RTLIB::TRUNC_PPCF128));
   3362     break;
   3363   case ISD::FFLOOR:
   3364     Results.push_back(ExpandFPLibCall(Node, RTLIB::FLOOR_F32, RTLIB::FLOOR_F64,
   3365                                       RTLIB::FLOOR_F80, RTLIB::FLOOR_PPCF128));
   3366     break;
   3367   case ISD::FCEIL:
   3368     Results.push_back(ExpandFPLibCall(Node, RTLIB::CEIL_F32, RTLIB::CEIL_F64,
   3369                                       RTLIB::CEIL_F80, RTLIB::CEIL_PPCF128));
   3370     break;
   3371   case ISD::FRINT:
   3372     Results.push_back(ExpandFPLibCall(Node, RTLIB::RINT_F32, RTLIB::RINT_F64,
   3373                                       RTLIB::RINT_F80, RTLIB::RINT_PPCF128));
   3374     break;
   3375   case ISD::FNEARBYINT:
   3376     Results.push_back(ExpandFPLibCall(Node, RTLIB::NEARBYINT_F32,
   3377                                       RTLIB::NEARBYINT_F64,
   3378                                       RTLIB::NEARBYINT_F80,
   3379                                       RTLIB::NEARBYINT_PPCF128));
   3380     break;
   3381   case ISD::FPOWI:
   3382     Results.push_back(ExpandFPLibCall(Node, RTLIB::POWI_F32, RTLIB::POWI_F64,
   3383                                       RTLIB::POWI_F80, RTLIB::POWI_PPCF128));
   3384     break;
   3385   case ISD::FPOW:
   3386     Results.push_back(ExpandFPLibCall(Node, RTLIB::POW_F32, RTLIB::POW_F64,
   3387                                       RTLIB::POW_F80, RTLIB::POW_PPCF128));
   3388     break;
   3389   case ISD::FDIV:
   3390     Results.push_back(ExpandFPLibCall(Node, RTLIB::DIV_F32, RTLIB::DIV_F64,
   3391                                       RTLIB::DIV_F80, RTLIB::DIV_PPCF128));
   3392     break;
   3393   case ISD::FREM:
   3394     Results.push_back(ExpandFPLibCall(Node, RTLIB::REM_F32, RTLIB::REM_F64,
   3395                                       RTLIB::REM_F80, RTLIB::REM_PPCF128));
   3396     break;
   3397   case ISD::FMA:
   3398     Results.push_back(ExpandFPLibCall(Node, RTLIB::FMA_F32, RTLIB::FMA_F64,
   3399                                       RTLIB::FMA_F80, RTLIB::FMA_PPCF128));
   3400     break;
   3401   case ISD::FP16_TO_FP32:
   3402     Results.push_back(ExpandLibCall(RTLIB::FPEXT_F16_F32, Node, false));
   3403     break;
   3404   case ISD::FP32_TO_FP16:
   3405     Results.push_back(ExpandLibCall(RTLIB::FPROUND_F32_F16, Node, false));
   3406     break;
   3407   case ISD::ConstantFP: {
   3408     ConstantFPSDNode *CFP = cast<ConstantFPSDNode>(Node);
   3409     // Check to see if this FP immediate is already legal.
   3410     // If this is a legal constant, turn it into a TargetConstantFP node.
   3411     if (TLI.isFPImmLegal(CFP->getValueAPF(), Node->getValueType(0)))
   3412       Results.push_back(SDValue(Node, 0));
   3413     else
   3414       Results.push_back(ExpandConstantFP(CFP, true, DAG, TLI));
   3415     break;
   3416   }
   3417   case ISD::EHSELECTION: {
   3418     unsigned Reg = TLI.getExceptionSelectorRegister();
   3419     assert(Reg && "Can't expand to unknown register!");
   3420     Results.push_back(DAG.getCopyFromReg(Node->getOperand(1), dl, Reg,
   3421                                          Node->getValueType(0)));
   3422     Results.push_back(Results[0].getValue(1));
   3423     break;
   3424   }
   3425   case ISD::EXCEPTIONADDR: {
   3426     unsigned Reg = TLI.getExceptionAddressRegister();
   3427     assert(Reg && "Can't expand to unknown register!");
   3428     Results.push_back(DAG.getCopyFromReg(Node->getOperand(0), dl, Reg,
   3429                                          Node->getValueType(0)));
   3430     Results.push_back(Results[0].getValue(1));
   3431     break;
   3432   }
   3433   case ISD::SUB: {
   3434     EVT VT = Node->getValueType(0);
   3435     assert(TLI.isOperationLegalOrCustom(ISD::ADD, VT) &&
   3436            TLI.isOperationLegalOrCustom(ISD::XOR, VT) &&
   3437            "Don't know how to expand this subtraction!");
   3438     Tmp1 = DAG.getNode(ISD::XOR, dl, VT, Node->getOperand(1),
   3439                DAG.getConstant(APInt::getAllOnesValue(VT.getSizeInBits()), VT));
   3440     Tmp1 = DAG.getNode(ISD::ADD, dl, VT, Tmp2, DAG.getConstant(1, VT));
   3441     Results.push_back(DAG.getNode(ISD::ADD, dl, VT, Node->getOperand(0), Tmp1));
   3442     break;
   3443   }
   3444   case ISD::UREM:
   3445   case ISD::SREM: {
   3446     EVT VT = Node->getValueType(0);
   3447     SDVTList VTs = DAG.getVTList(VT, VT);
   3448     bool isSigned = Node->getOpcode() == ISD::SREM;
   3449     unsigned DivOpc = isSigned ? ISD::SDIV : ISD::UDIV;
   3450     unsigned DivRemOpc = isSigned ? ISD::SDIVREM : ISD::UDIVREM;
   3451     Tmp2 = Node->getOperand(0);
   3452     Tmp3 = Node->getOperand(1);
   3453     if (TLI.isOperationLegalOrCustom(DivRemOpc, VT) ||
   3454         (isDivRemLibcallAvailable(Node, isSigned, TLI) &&
   3455          UseDivRem(Node, isSigned, false))) {
   3456       Tmp1 = DAG.getNode(DivRemOpc, dl, VTs, Tmp2, Tmp3).getValue(1);
   3457     } else if (TLI.isOperationLegalOrCustom(DivOpc, VT)) {
   3458       // X % Y -> X-X/Y*Y
   3459       Tmp1 = DAG.getNode(DivOpc, dl, VT, Tmp2, Tmp3);
   3460       Tmp1 = DAG.getNode(ISD::MUL, dl, VT, Tmp1, Tmp3);
   3461       Tmp1 = DAG.getNode(ISD::SUB, dl, VT, Tmp2, Tmp1);
   3462     } else if (isSigned)
   3463       Tmp1 = ExpandIntLibCall(Node, true,
   3464                               RTLIB::SREM_I8,
   3465                               RTLIB::SREM_I16, RTLIB::SREM_I32,
   3466                               RTLIB::SREM_I64, RTLIB::SREM_I128);
   3467     else
   3468       Tmp1 = ExpandIntLibCall(Node, false,
   3469                               RTLIB::UREM_I8,
   3470                               RTLIB::UREM_I16, RTLIB::UREM_I32,
   3471                               RTLIB::UREM_I64, RTLIB::UREM_I128);
   3472     Results.push_back(Tmp1);
   3473     break;
   3474   }
   3475   case ISD::UDIV:
   3476   case ISD::SDIV: {
   3477     bool isSigned = Node->getOpcode() == ISD::SDIV;
   3478     unsigned DivRemOpc = isSigned ? ISD::SDIVREM : ISD::UDIVREM;
   3479     EVT VT = Node->getValueType(0);
   3480     SDVTList VTs = DAG.getVTList(VT, VT);
   3481     if (TLI.isOperationLegalOrCustom(DivRemOpc, VT) ||
   3482         (isDivRemLibcallAvailable(Node, isSigned, TLI) &&
   3483          UseDivRem(Node, isSigned, true)))
   3484       Tmp1 = DAG.getNode(DivRemOpc, dl, VTs, Node->getOperand(0),
   3485                          Node->getOperand(1));
   3486     else if (isSigned)
   3487       Tmp1 = ExpandIntLibCall(Node, true,
   3488                               RTLIB::SDIV_I8,
   3489                               RTLIB::SDIV_I16, RTLIB::SDIV_I32,
   3490                               RTLIB::SDIV_I64, RTLIB::SDIV_I128);
   3491     else
   3492       Tmp1 = ExpandIntLibCall(Node, false,
   3493                               RTLIB::UDIV_I8,
   3494                               RTLIB::UDIV_I16, RTLIB::UDIV_I32,
   3495                               RTLIB::UDIV_I64, RTLIB::UDIV_I128);
   3496     Results.push_back(Tmp1);
   3497     break;
   3498   }
   3499   case ISD::MULHU:
   3500   case ISD::MULHS: {
   3501     unsigned ExpandOpcode = Node->getOpcode() == ISD::MULHU ? ISD::UMUL_LOHI :
   3502                                                               ISD::SMUL_LOHI;
   3503     EVT VT = Node->getValueType(0);
   3504     SDVTList VTs = DAG.getVTList(VT, VT);
   3505     assert(TLI.isOperationLegalOrCustom(ExpandOpcode, VT) &&
   3506            "If this wasn't legal, it shouldn't have been created!");
   3507     Tmp1 = DAG.getNode(ExpandOpcode, dl, VTs, Node->getOperand(0),
   3508                        Node->getOperand(1));
   3509     Results.push_back(Tmp1.getValue(1));
   3510     break;
   3511   }
   3512   case ISD::SDIVREM:
   3513   case ISD::UDIVREM:
   3514     // Expand into divrem libcall
   3515     ExpandDivRemLibCall(Node, Results);
   3516     break;
   3517   case ISD::MUL: {
   3518     EVT VT = Node->getValueType(0);
   3519     SDVTList VTs = DAG.getVTList(VT, VT);
   3520     // See if multiply or divide can be lowered using two-result operations.
   3521     // We just need the low half of the multiply; try both the signed
   3522     // and unsigned forms. If the target supports both SMUL_LOHI and
   3523     // UMUL_LOHI, form a preference by checking which forms of plain
   3524     // MULH it supports.
   3525     bool HasSMUL_LOHI = TLI.isOperationLegalOrCustom(ISD::SMUL_LOHI, VT);
   3526     bool HasUMUL_LOHI = TLI.isOperationLegalOrCustom(ISD::UMUL_LOHI, VT);
   3527     bool HasMULHS = TLI.isOperationLegalOrCustom(ISD::MULHS, VT);
   3528     bool HasMULHU = TLI.isOperationLegalOrCustom(ISD::MULHU, VT);
   3529     unsigned OpToUse = 0;
   3530     if (HasSMUL_LOHI && !HasMULHS) {
   3531       OpToUse = ISD::SMUL_LOHI;
   3532     } else if (HasUMUL_LOHI && !HasMULHU) {
   3533       OpToUse = ISD::UMUL_LOHI;
   3534     } else if (HasSMUL_LOHI) {
   3535       OpToUse = ISD::SMUL_LOHI;
   3536     } else if (HasUMUL_LOHI) {
   3537       OpToUse = ISD::UMUL_LOHI;
   3538     }
   3539     if (OpToUse) {
   3540       Results.push_back(DAG.getNode(OpToUse, dl, VTs, Node->getOperand(0),
   3541                                     Node->getOperand(1)));
   3542       break;
   3543     }
   3544     Tmp1 = ExpandIntLibCall(Node, false,
   3545                             RTLIB::MUL_I8,
   3546                             RTLIB::MUL_I16, RTLIB::MUL_I32,
   3547                             RTLIB::MUL_I64, RTLIB::MUL_I128);
   3548     Results.push_back(Tmp1);
   3549     break;
   3550   }
   3551   case ISD::SADDO:
   3552   case ISD::SSUBO: {
   3553     SDValue LHS = Node->getOperand(0);
   3554     SDValue RHS = Node->getOperand(1);
   3555     SDValue Sum = DAG.getNode(Node->getOpcode() == ISD::SADDO ?
   3556                               ISD::ADD : ISD::SUB, dl, LHS.getValueType(),
   3557                               LHS, RHS);
   3558     Results.push_back(Sum);
   3559     EVT OType = Node->getValueType(1);
   3560 
   3561     SDValue Zero = DAG.getConstant(0, LHS.getValueType());
   3562 
   3563     //   LHSSign -> LHS >= 0
   3564     //   RHSSign -> RHS >= 0
   3565     //   SumSign -> Sum >= 0
   3566     //
   3567     //   Add:
   3568     //   Overflow -> (LHSSign == RHSSign) && (LHSSign != SumSign)
   3569     //   Sub:
   3570     //   Overflow -> (LHSSign != RHSSign) && (LHSSign != SumSign)
   3571     //
   3572     SDValue LHSSign = DAG.getSetCC(dl, OType, LHS, Zero, ISD::SETGE);
   3573     SDValue RHSSign = DAG.getSetCC(dl, OType, RHS, Zero, ISD::SETGE);
   3574     SDValue SignsMatch = DAG.getSetCC(dl, OType, LHSSign, RHSSign,
   3575                                       Node->getOpcode() == ISD::SADDO ?
   3576                                       ISD::SETEQ : ISD::SETNE);
   3577 
   3578     SDValue SumSign = DAG.getSetCC(dl, OType, Sum, Zero, ISD::SETGE);
   3579     SDValue SumSignNE = DAG.getSetCC(dl, OType, LHSSign, SumSign, ISD::SETNE);
   3580 
   3581     SDValue Cmp = DAG.getNode(ISD::AND, dl, OType, SignsMatch, SumSignNE);
   3582     Results.push_back(Cmp);
   3583     break;
   3584   }
   3585   case ISD::UADDO:
   3586   case ISD::USUBO: {
   3587     SDValue LHS = Node->getOperand(0);
   3588     SDValue RHS = Node->getOperand(1);
   3589     SDValue Sum = DAG.getNode(Node->getOpcode() == ISD::UADDO ?
   3590                               ISD::ADD : ISD::SUB, dl, LHS.getValueType(),
   3591                               LHS, RHS);
   3592     Results.push_back(Sum);
   3593     Results.push_back(DAG.getSetCC(dl, Node->getValueType(1), Sum, LHS,
   3594                                    Node->getOpcode () == ISD::UADDO ?
   3595                                    ISD::SETULT : ISD::SETUGT));
   3596     break;
   3597   }
   3598   case ISD::UMULO:
   3599   case ISD::SMULO: {
   3600     EVT VT = Node->getValueType(0);
   3601     EVT WideVT = EVT::getIntegerVT(*DAG.getContext(), VT.getSizeInBits() * 2);
   3602     SDValue LHS = Node->getOperand(0);
   3603     SDValue RHS = Node->getOperand(1);
   3604     SDValue BottomHalf;
   3605     SDValue TopHalf;
   3606     static const unsigned Ops[2][3] =
   3607         { { ISD::MULHU, ISD::UMUL_LOHI, ISD::ZERO_EXTEND },
   3608           { ISD::MULHS, ISD::SMUL_LOHI, ISD::SIGN_EXTEND }};
   3609     bool isSigned = Node->getOpcode() == ISD::SMULO;
   3610     if (TLI.isOperationLegalOrCustom(Ops[isSigned][0], VT)) {
   3611       BottomHalf = DAG.getNode(ISD::MUL, dl, VT, LHS, RHS);
   3612       TopHalf = DAG.getNode(Ops[isSigned][0], dl, VT, LHS, RHS);
   3613     } else if (TLI.isOperationLegalOrCustom(Ops[isSigned][1], VT)) {
   3614       BottomHalf = DAG.getNode(Ops[isSigned][1], dl, DAG.getVTList(VT, VT), LHS,
   3615                                RHS);
   3616       TopHalf = BottomHalf.getValue(1);
   3617     } else if (TLI.isTypeLegal(EVT::getIntegerVT(*DAG.getContext(),
   3618                                                  VT.getSizeInBits() * 2))) {
   3619       LHS = DAG.getNode(Ops[isSigned][2], dl, WideVT, LHS);
   3620       RHS = DAG.getNode(Ops[isSigned][2], dl, WideVT, RHS);
   3621       Tmp1 = DAG.getNode(ISD::MUL, dl, WideVT, LHS, RHS);
   3622       BottomHalf = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, VT, Tmp1,
   3623                                DAG.getIntPtrConstant(0));
   3624       TopHalf = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, VT, Tmp1,
   3625                             DAG.getIntPtrConstant(1));
   3626     } else {
   3627       // We can fall back to a libcall with an illegal type for the MUL if we
   3628       // have a libcall big enough.
   3629       // Also, we can fall back to a division in some cases, but that's a big
   3630       // performance hit in the general case.
   3631       RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
   3632       if (WideVT == MVT::i16)
   3633         LC = RTLIB::MUL_I16;
   3634       else if (WideVT == MVT::i32)
   3635         LC = RTLIB::MUL_I32;
   3636       else if (WideVT == MVT::i64)
   3637         LC = RTLIB::MUL_I64;
   3638       else if (WideVT == MVT::i128)
   3639         LC = RTLIB::MUL_I128;
   3640       assert(LC != RTLIB::UNKNOWN_LIBCALL && "Cannot expand this operation!");
   3641 
   3642       // The high part is obtained by SRA'ing all but one of the bits of low
   3643       // part.
   3644       unsigned LoSize = VT.getSizeInBits();
   3645       SDValue HiLHS = DAG.getNode(ISD::SRA, dl, VT, RHS,
   3646                                 DAG.getConstant(LoSize-1, TLI.getPointerTy()));
   3647       SDValue HiRHS = DAG.getNode(ISD::SRA, dl, VT, LHS,
   3648                                 DAG.getConstant(LoSize-1, TLI.getPointerTy()));
   3649 
   3650       // Here we're passing the 2 arguments explicitly as 4 arguments that are
   3651       // pre-lowered to the correct types. This all depends upon WideVT not
   3652       // being a legal type for the architecture and thus has to be split to
   3653       // two arguments.
   3654       SDValue Args[] = { LHS, HiLHS, RHS, HiRHS };
   3655       SDValue Ret = ExpandLibCall(LC, WideVT, Args, 4, isSigned, dl);
   3656       BottomHalf = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, VT, Ret,
   3657                                DAG.getIntPtrConstant(0));
   3658       TopHalf = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, VT, Ret,
   3659                             DAG.getIntPtrConstant(1));
   3660     }
   3661 
   3662     if (isSigned) {
   3663       Tmp1 = DAG.getConstant(VT.getSizeInBits() - 1,
   3664                              TLI.getShiftAmountTy(BottomHalf.getValueType()));
   3665       Tmp1 = DAG.getNode(ISD::SRA, dl, VT, BottomHalf, Tmp1);
   3666       TopHalf = DAG.getSetCC(dl, TLI.getSetCCResultType(VT), TopHalf, Tmp1,
   3667                              ISD::SETNE);
   3668     } else {
   3669       TopHalf = DAG.getSetCC(dl, TLI.getSetCCResultType(VT), TopHalf,
   3670                              DAG.getConstant(0, VT), ISD::SETNE);
   3671     }
   3672     Results.push_back(BottomHalf);
   3673     Results.push_back(TopHalf);
   3674     break;
   3675   }
   3676   case ISD::BUILD_PAIR: {
   3677     EVT PairTy = Node->getValueType(0);
   3678     Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, PairTy, Node->getOperand(0));
   3679     Tmp2 = DAG.getNode(ISD::ANY_EXTEND, dl, PairTy, Node->getOperand(1));
   3680     Tmp2 = DAG.getNode(ISD::SHL, dl, PairTy, Tmp2,
   3681                        DAG.getConstant(PairTy.getSizeInBits()/2,
   3682                                        TLI.getShiftAmountTy(PairTy)));
   3683     Results.push_back(DAG.getNode(ISD::OR, dl, PairTy, Tmp1, Tmp2));
   3684     break;
   3685   }
   3686   case ISD::SELECT:
   3687     Tmp1 = Node->getOperand(0);
   3688     Tmp2 = Node->getOperand(1);
   3689     Tmp3 = Node->getOperand(2);
   3690     if (Tmp1.getOpcode() == ISD::SETCC) {
   3691       Tmp1 = DAG.getSelectCC(dl, Tmp1.getOperand(0), Tmp1.getOperand(1),
   3692                              Tmp2, Tmp3,
   3693                              cast<CondCodeSDNode>(Tmp1.getOperand(2))->get());
   3694     } else {
   3695       Tmp1 = DAG.getSelectCC(dl, Tmp1,
   3696                              DAG.getConstant(0, Tmp1.getValueType()),
   3697                              Tmp2, Tmp3, ISD::SETNE);
   3698     }
   3699     Results.push_back(Tmp1);
   3700     break;
   3701   case ISD::BR_JT: {
   3702     SDValue Chain = Node->getOperand(0);
   3703     SDValue Table = Node->getOperand(1);
   3704     SDValue Index = Node->getOperand(2);
   3705 
   3706     EVT PTy = TLI.getPointerTy();
   3707 
   3708     const TargetData &TD = *TLI.getTargetData();
   3709     unsigned EntrySize =
   3710       DAG.getMachineFunction().getJumpTableInfo()->getEntrySize(TD);
   3711 
   3712     Index = DAG.getNode(ISD::MUL, dl, PTy,
   3713                         Index, DAG.getConstant(EntrySize, PTy));
   3714     SDValue Addr = DAG.getNode(ISD::ADD, dl, PTy, Index, Table);
   3715 
   3716     EVT MemVT = EVT::getIntegerVT(*DAG.getContext(), EntrySize * 8);
   3717     SDValue LD = DAG.getExtLoad(ISD::SEXTLOAD, dl, PTy, Chain, Addr,
   3718                                 MachinePointerInfo::getJumpTable(), MemVT,
   3719                                 false, false, 0);
   3720     Addr = LD;
   3721     if (TM.getRelocationModel() == Reloc::PIC_) {
   3722       // For PIC, the sequence is:
   3723       // BRIND(load(Jumptable + index) + RelocBase)
   3724       // RelocBase can be JumpTable, GOT or some sort of global base.
   3725       Addr = DAG.getNode(ISD::ADD, dl, PTy, Addr,
   3726                           TLI.getPICJumpTableRelocBase(Table, DAG));
   3727     }
   3728     Tmp1 = DAG.getNode(ISD::BRIND, dl, MVT::Other, LD.getValue(1), Addr);
   3729     Results.push_back(Tmp1);
   3730     break;
   3731   }
   3732   case ISD::BRCOND:
   3733     // Expand brcond's setcc into its constituent parts and create a BR_CC
   3734     // Node.
   3735     Tmp1 = Node->getOperand(0);
   3736     Tmp2 = Node->getOperand(1);
   3737     if (Tmp2.getOpcode() == ISD::SETCC) {
   3738       Tmp1 = DAG.getNode(ISD::BR_CC, dl, MVT::Other,
   3739                          Tmp1, Tmp2.getOperand(2),
   3740                          Tmp2.getOperand(0), Tmp2.getOperand(1),
   3741                          Node->getOperand(2));
   3742     } else {
   3743       // We test only the i1 bit.  Skip the AND if UNDEF.
   3744       Tmp3 = (Tmp2.getOpcode() == ISD::UNDEF) ? Tmp2 :
   3745         DAG.getNode(ISD::AND, dl, Tmp2.getValueType(), Tmp2,
   3746                     DAG.getConstant(1, Tmp2.getValueType()));
   3747       Tmp1 = DAG.getNode(ISD::BR_CC, dl, MVT::Other, Tmp1,
   3748                          DAG.getCondCode(ISD::SETNE), Tmp3,
   3749                          DAG.getConstant(0, Tmp3.getValueType()),
   3750                          Node->getOperand(2));
   3751     }
   3752     Results.push_back(Tmp1);
   3753     break;
   3754   case ISD::SETCC: {
   3755     Tmp1 = Node->getOperand(0);
   3756     Tmp2 = Node->getOperand(1);
   3757     Tmp3 = Node->getOperand(2);
   3758     LegalizeSetCCCondCode(Node->getValueType(0), Tmp1, Tmp2, Tmp3, dl);
   3759 
   3760     // If we expanded the SETCC into an AND/OR, return the new node
   3761     if (Tmp2.getNode() == 0) {
   3762       Results.push_back(Tmp1);
   3763       break;
   3764     }
   3765 
   3766     // Otherwise, SETCC for the given comparison type must be completely
   3767     // illegal; expand it into a SELECT_CC.
   3768     EVT VT = Node->getValueType(0);
   3769     Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, VT, Tmp1, Tmp2,
   3770                        DAG.getConstant(1, VT), DAG.getConstant(0, VT), Tmp3);
   3771     Results.push_back(Tmp1);
   3772     break;
   3773   }
   3774   case ISD::SELECT_CC: {
   3775     Tmp1 = Node->getOperand(0);   // LHS
   3776     Tmp2 = Node->getOperand(1);   // RHS
   3777     Tmp3 = Node->getOperand(2);   // True
   3778     Tmp4 = Node->getOperand(3);   // False
   3779     SDValue CC = Node->getOperand(4);
   3780 
   3781     LegalizeSetCCCondCode(TLI.getSetCCResultType(Tmp1.getValueType()),
   3782                           Tmp1, Tmp2, CC, dl);
   3783 
   3784     assert(!Tmp2.getNode() && "Can't legalize SELECT_CC with legal condition!");
   3785     Tmp2 = DAG.getConstant(0, Tmp1.getValueType());
   3786     CC = DAG.getCondCode(ISD::SETNE);
   3787     Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, Node->getValueType(0), Tmp1, Tmp2,
   3788                        Tmp3, Tmp4, CC);
   3789     Results.push_back(Tmp1);
   3790     break;
   3791   }
   3792   case ISD::BR_CC: {
   3793     Tmp1 = Node->getOperand(0);              // Chain
   3794     Tmp2 = Node->getOperand(2);              // LHS
   3795     Tmp3 = Node->getOperand(3);              // RHS
   3796     Tmp4 = Node->getOperand(1);              // CC
   3797 
   3798     LegalizeSetCCCondCode(TLI.getSetCCResultType(Tmp2.getValueType()),
   3799                           Tmp2, Tmp3, Tmp4, dl);
   3800     LastCALLSEQ_END = DAG.getEntryNode();
   3801 
   3802     assert(!Tmp3.getNode() && "Can't legalize BR_CC with legal condition!");
   3803     Tmp3 = DAG.getConstant(0, Tmp2.getValueType());
   3804     Tmp4 = DAG.getCondCode(ISD::SETNE);
   3805     Tmp1 = DAG.getNode(ISD::BR_CC, dl, Node->getValueType(0), Tmp1, Tmp4, Tmp2,
   3806                        Tmp3, Node->getOperand(4));
   3807     Results.push_back(Tmp1);
   3808     break;
   3809   }
   3810   case ISD::GLOBAL_OFFSET_TABLE:
   3811   case ISD::GlobalAddress:
   3812   case ISD::GlobalTLSAddress:
   3813   case ISD::ExternalSymbol:
   3814   case ISD::ConstantPool:
   3815   case ISD::JumpTable:
   3816   case ISD::INTRINSIC_W_CHAIN:
   3817   case ISD::INTRINSIC_WO_CHAIN:
   3818   case ISD::INTRINSIC_VOID:
   3819     // FIXME: Custom lowering for these operations shouldn't return null!
   3820     for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
   3821       Results.push_back(SDValue(Node, i));
   3822     break;
   3823   }
   3824 }
   3825 void SelectionDAGLegalize::PromoteNode(SDNode *Node,
   3826                                        SmallVectorImpl<SDValue> &Results) {
   3827   EVT OVT = Node->getValueType(0);
   3828   if (Node->getOpcode() == ISD::UINT_TO_FP ||
   3829       Node->getOpcode() == ISD::SINT_TO_FP ||
   3830       Node->getOpcode() == ISD::SETCC) {
   3831     OVT = Node->getOperand(0).getValueType();
   3832   }
   3833   EVT NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), OVT);
   3834   DebugLoc dl = Node->getDebugLoc();
   3835   SDValue Tmp1, Tmp2, Tmp3;
   3836   switch (Node->getOpcode()) {
   3837   case ISD::CTTZ:
   3838   case ISD::CTLZ:
   3839   case ISD::CTPOP:
   3840     // Zero extend the argument.
   3841     Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, NVT, Node->getOperand(0));
   3842     // Perform the larger operation.
   3843     Tmp1 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1);
   3844     if (Node->getOpcode() == ISD::CTTZ) {
   3845       //if Tmp1 == sizeinbits(NVT) then Tmp1 = sizeinbits(Old VT)
   3846       Tmp2 = DAG.getSetCC(dl, TLI.getSetCCResultType(NVT),
   3847                           Tmp1, DAG.getConstant(NVT.getSizeInBits(), NVT),
   3848                           ISD::SETEQ);
   3849       Tmp1 = DAG.getNode(ISD::SELECT, dl, NVT, Tmp2,
   3850                           DAG.getConstant(OVT.getSizeInBits(), NVT), Tmp1);
   3851     } else if (Node->getOpcode() == ISD::CTLZ) {
   3852       // Tmp1 = Tmp1 - (sizeinbits(NVT) - sizeinbits(Old VT))
   3853       Tmp1 = DAG.getNode(ISD::SUB, dl, NVT, Tmp1,
   3854                           DAG.getConstant(NVT.getSizeInBits() -
   3855                                           OVT.getSizeInBits(), NVT));
   3856     }
   3857     Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp1));
   3858     break;
   3859   case ISD::BSWAP: {
   3860     unsigned DiffBits = NVT.getSizeInBits() - OVT.getSizeInBits();
   3861     Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, NVT, Node->getOperand(0));
   3862     Tmp1 = DAG.getNode(ISD::BSWAP, dl, NVT, Tmp1);
   3863     Tmp1 = DAG.getNode(ISD::SRL, dl, NVT, Tmp1,
   3864                           DAG.getConstant(DiffBits, TLI.getShiftAmountTy(NVT)));
   3865     Results.push_back(Tmp1);
   3866     break;
   3867   }
   3868   case ISD::FP_TO_UINT:
   3869   case ISD::FP_TO_SINT:
   3870     Tmp1 = PromoteLegalFP_TO_INT(Node->getOperand(0), Node->getValueType(0),
   3871                                  Node->getOpcode() == ISD::FP_TO_SINT, dl);
   3872     Results.push_back(Tmp1);
   3873     break;
   3874   case ISD::UINT_TO_FP:
   3875   case ISD::SINT_TO_FP:
   3876     Tmp1 = PromoteLegalINT_TO_FP(Node->getOperand(0), Node->getValueType(0),
   3877                                  Node->getOpcode() == ISD::SINT_TO_FP, dl);
   3878     Results.push_back(Tmp1);
   3879     break;
   3880   case ISD::AND:
   3881   case ISD::OR:
   3882   case ISD::XOR: {
   3883     unsigned ExtOp, TruncOp;
   3884     if (OVT.isVector()) {
   3885       ExtOp   = ISD::BITCAST;
   3886       TruncOp = ISD::BITCAST;
   3887     } else {
   3888       assert(OVT.isInteger() && "Cannot promote logic operation");
   3889       ExtOp   = ISD::ANY_EXTEND;
   3890       TruncOp = ISD::TRUNCATE;
   3891     }
   3892     // Promote each of the values to the new type.
   3893     Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(0));
   3894     Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
   3895     // Perform the larger operation, then convert back
   3896     Tmp1 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2);
   3897     Results.push_back(DAG.getNode(TruncOp, dl, OVT, Tmp1));
   3898     break;
   3899   }
   3900   case ISD::SELECT: {
   3901     unsigned ExtOp, TruncOp;
   3902     if (Node->getValueType(0).isVector()) {
   3903       ExtOp   = ISD::BITCAST;
   3904       TruncOp = ISD::BITCAST;
   3905     } else if (Node->getValueType(0).isInteger()) {
   3906       ExtOp   = ISD::ANY_EXTEND;
   3907       TruncOp = ISD::TRUNCATE;
   3908     } else {
   3909       ExtOp   = ISD::FP_EXTEND;
   3910       TruncOp = ISD::FP_ROUND;
   3911     }
   3912     Tmp1 = Node->getOperand(0);
   3913     // Promote each of the values to the new type.
   3914     Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
   3915     Tmp3 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(2));
   3916     // Perform the larger operation, then round down.
   3917     Tmp1 = DAG.getNode(ISD::SELECT, dl, NVT, Tmp1, Tmp2, Tmp3);
   3918     if (TruncOp != ISD::FP_ROUND)
   3919       Tmp1 = DAG.getNode(TruncOp, dl, Node->getValueType(0), Tmp1);
   3920     else
   3921       Tmp1 = DAG.getNode(TruncOp, dl, Node->getValueType(0), Tmp1,
   3922                          DAG.getIntPtrConstant(0));
   3923     Results.push_back(Tmp1);
   3924     break;
   3925   }
   3926   case ISD::VECTOR_SHUFFLE: {
   3927     SmallVector<int, 8> Mask;
   3928     cast<ShuffleVectorSDNode>(Node)->getMask(Mask);
   3929 
   3930     // Cast the two input vectors.
   3931     Tmp1 = DAG.getNode(ISD::BITCAST, dl, NVT, Node->getOperand(0));
   3932     Tmp2 = DAG.getNode(ISD::BITCAST, dl, NVT, Node->getOperand(1));
   3933 
   3934     // Convert the shuffle mask to the right # elements.
   3935     Tmp1 = ShuffleWithNarrowerEltType(NVT, OVT, dl, Tmp1, Tmp2, Mask);
   3936     Tmp1 = DAG.getNode(ISD::BITCAST, dl, OVT, Tmp1);
   3937     Results.push_back(Tmp1);
   3938     break;
   3939   }
   3940   case ISD::SETCC: {
   3941     unsigned ExtOp = ISD::FP_EXTEND;
   3942     if (NVT.isInteger()) {
   3943       ISD::CondCode CCCode =
   3944         cast<CondCodeSDNode>(Node->getOperand(2))->get();
   3945       ExtOp = isSignedIntSetCC(CCCode) ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND;
   3946     }
   3947     Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(0));
   3948     Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
   3949     Results.push_back(DAG.getNode(ISD::SETCC, dl, Node->getValueType(0),
   3950                                   Tmp1, Tmp2, Node->getOperand(2)));
   3951     break;
   3952   }
   3953   }
   3954 }
   3955 
   3956 // SelectionDAG::Legalize - This is the entry point for the file.
   3957 //
   3958 void SelectionDAG::Legalize() {
   3959   /// run - This is the main entry point to this class.
   3960   ///
   3961   SelectionDAGLegalize(*this).LegalizeDAG();
   3962 }
   3963