LegalizeDAG.cpp revision 226633
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"
34using 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///
48namespace {
49class 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
81public:
82  explicit SelectionDAGLegalize(SelectionDAG &DAG);
83
84  void LegalizeDAG();
85
86private:
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>
164SDValue
165SelectionDAGLegalize::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
192SelectionDAGLegalize::SelectionDAGLegalize(SelectionDAG &dag)
193  : TM(dag.getTarget()), TLI(dag.getTargetLoweringInfo()),
194    DAG(dag) {
195}
196
197void 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.
226static 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.
273static 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///
303bool 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.
335static 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.
383static
384SDValue 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.
495static
496SDValue 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.
637SDValue SelectionDAGLegalize::
638PerformInsertVectorEltInMemory(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
679SDValue SelectionDAGLegalize::
680ExpandINSERT_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
706SDValue 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.
766SDValue 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
1757SDValue 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
1788SDValue 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
1832SDValue 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
1882SDValue 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
1943void 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.
1980void 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.
2025SDValue 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
2068SDValue 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.
2090SDValue 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.
2191SDValue 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.
2237SDValue 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.
2271std::pair<SDValue, SDValue>
2272SelectionDAGLegalize::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
2307SDValue 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
2323SDValue 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.
2342static 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.
2359static 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.
2383void
2384SelectionDAGLegalize::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.
2452SDValue 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.
2649SDValue 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.
2691SDValue 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///
2729SDValue 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.
2776static 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///
2788SDValue 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
2876std::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
2962void 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}
3825void 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//
3958void SelectionDAG::Legalize() {
3959  /// run - This is the main entry point to this class.
3960  ///
3961  SelectionDAGLegalize(*this).LegalizeDAG();
3962}
3963