LegalizeDAG.cpp revision 34525f9ac098c1c6bc9002886d6da3039a284fd2
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/CodeGen/SelectionDAG.h"
15#include "llvm/ADT/DenseMap.h"
16#include "llvm/ADT/SmallPtrSet.h"
17#include "llvm/ADT/SmallVector.h"
18#include "llvm/CallingConv.h"
19#include "llvm/CodeGen/Analysis.h"
20#include "llvm/CodeGen/MachineFunction.h"
21#include "llvm/CodeGen/MachineJumpTableInfo.h"
22#include "llvm/Constants.h"
23#include "llvm/DataLayout.h"
24#include "llvm/DebugInfo.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/Target/TargetFrameLowering.h"
32#include "llvm/Target/TargetLowering.h"
33#include "llvm/Target/TargetMachine.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 : public SelectionDAG::DAGUpdateListener {
50  const TargetMachine &TM;
51  const TargetLowering &TLI;
52  SelectionDAG &DAG;
53
54  /// LegalizePosition - The iterator for walking through the node list.
55  SelectionDAG::allnodes_iterator LegalizePosition;
56
57  /// LegalizedNodes - The set of nodes which have already been legalized.
58  SmallPtrSet<SDNode *, 16> LegalizedNodes;
59
60  // Libcall insertion helpers.
61
62public:
63  explicit SelectionDAGLegalize(SelectionDAG &DAG);
64
65  void LegalizeDAG();
66
67private:
68  /// LegalizeOp - Legalizes the given operation.
69  void LegalizeOp(SDNode *Node);
70
71  SDValue OptimizeFloatStore(StoreSDNode *ST);
72
73  void LegalizeLoadOps(SDNode *Node);
74  void LegalizeStoreOps(SDNode *Node);
75
76  /// PerformInsertVectorEltInMemory - Some target cannot handle a variable
77  /// insertion index for the INSERT_VECTOR_ELT instruction.  In this case, it
78  /// is necessary to spill the vector being inserted into to memory, perform
79  /// the insert there, and then read the result back.
80  SDValue PerformInsertVectorEltInMemory(SDValue Vec, SDValue Val,
81                                         SDValue Idx, DebugLoc dl);
82  SDValue ExpandINSERT_VECTOR_ELT(SDValue Vec, SDValue Val,
83                                  SDValue Idx, DebugLoc dl);
84
85  /// ShuffleWithNarrowerEltType - Return a vector shuffle operation which
86  /// performs the same shuffe in terms of order or result bytes, but on a type
87  /// whose vector element type is narrower than the original shuffle type.
88  /// e.g. <v4i32> <0, 1, 0, 1> -> v8i16 <0, 1, 2, 3, 0, 1, 2, 3>
89  SDValue ShuffleWithNarrowerEltType(EVT NVT, EVT VT, DebugLoc dl,
90                                     SDValue N1, SDValue N2,
91                                     ArrayRef<int> Mask) const;
92
93  void LegalizeSetCCCondCode(EVT VT, SDValue &LHS, SDValue &RHS, SDValue &CC,
94                             DebugLoc dl);
95
96  SDValue ExpandLibCall(RTLIB::Libcall LC, SDNode *Node, bool isSigned);
97  SDValue ExpandLibCall(RTLIB::Libcall LC, EVT RetVT, const SDValue *Ops,
98                        unsigned NumOps, bool isSigned, DebugLoc dl);
99
100  std::pair<SDValue, SDValue> ExpandChainLibCall(RTLIB::Libcall LC,
101                                                 SDNode *Node, bool isSigned);
102  SDValue ExpandFPLibCall(SDNode *Node, RTLIB::Libcall Call_F32,
103                          RTLIB::Libcall Call_F64, RTLIB::Libcall Call_F80,
104                          RTLIB::Libcall Call_PPCF128);
105  SDValue ExpandIntLibCall(SDNode *Node, bool isSigned,
106                           RTLIB::Libcall Call_I8,
107                           RTLIB::Libcall Call_I16,
108                           RTLIB::Libcall Call_I32,
109                           RTLIB::Libcall Call_I64,
110                           RTLIB::Libcall Call_I128);
111  void ExpandDivRemLibCall(SDNode *Node, SmallVectorImpl<SDValue> &Results);
112
113  SDValue EmitStackConvert(SDValue SrcOp, EVT SlotVT, EVT DestVT, DebugLoc dl);
114  SDValue ExpandBUILD_VECTOR(SDNode *Node);
115  SDValue ExpandSCALAR_TO_VECTOR(SDNode *Node);
116  void ExpandDYNAMIC_STACKALLOC(SDNode *Node,
117                                SmallVectorImpl<SDValue> &Results);
118  SDValue ExpandFCOPYSIGN(SDNode *Node);
119  SDValue ExpandLegalINT_TO_FP(bool isSigned, SDValue LegalOp, EVT DestVT,
120                               DebugLoc dl);
121  SDValue PromoteLegalINT_TO_FP(SDValue LegalOp, EVT DestVT, bool isSigned,
122                                DebugLoc dl);
123  SDValue PromoteLegalFP_TO_INT(SDValue LegalOp, EVT DestVT, bool isSigned,
124                                DebugLoc dl);
125
126  SDValue ExpandBSWAP(SDValue Op, DebugLoc dl);
127  SDValue ExpandBitCount(unsigned Opc, SDValue Op, DebugLoc dl);
128
129  SDValue ExpandExtractFromVectorThroughStack(SDValue Op);
130  SDValue ExpandInsertToVectorThroughStack(SDValue Op);
131  SDValue ExpandVectorBuildThroughStack(SDNode* Node);
132
133  SDValue ExpandConstantFP(ConstantFPSDNode *CFP, bool UseCP);
134
135  std::pair<SDValue, SDValue> ExpandAtomic(SDNode *Node);
136
137  void ExpandNode(SDNode *Node);
138  void PromoteNode(SDNode *Node);
139
140  void ForgetNode(SDNode *N) {
141    LegalizedNodes.erase(N);
142    if (LegalizePosition == SelectionDAG::allnodes_iterator(N))
143      ++LegalizePosition;
144  }
145
146public:
147  // DAGUpdateListener implementation.
148  virtual void NodeDeleted(SDNode *N, SDNode *E) {
149    ForgetNode(N);
150  }
151  virtual void NodeUpdated(SDNode *N) {}
152
153  // Node replacement helpers
154  void ReplacedNode(SDNode *N) {
155    if (N->use_empty()) {
156      DAG.RemoveDeadNode(N);
157    } else {
158      ForgetNode(N);
159    }
160  }
161  void ReplaceNode(SDNode *Old, SDNode *New) {
162    DAG.ReplaceAllUsesWith(Old, New);
163    ReplacedNode(Old);
164  }
165  void ReplaceNode(SDValue Old, SDValue New) {
166    DAG.ReplaceAllUsesWith(Old, New);
167    ReplacedNode(Old.getNode());
168  }
169  void ReplaceNode(SDNode *Old, const SDValue *New) {
170    DAG.ReplaceAllUsesWith(Old, New);
171    ReplacedNode(Old);
172  }
173};
174}
175
176/// ShuffleWithNarrowerEltType - Return a vector shuffle operation which
177/// performs the same shuffe in terms of order or result bytes, but on a type
178/// whose vector element type is narrower than the original shuffle type.
179/// e.g. <v4i32> <0, 1, 0, 1> -> v8i16 <0, 1, 2, 3, 0, 1, 2, 3>
180SDValue
181SelectionDAGLegalize::ShuffleWithNarrowerEltType(EVT NVT, EVT VT,  DebugLoc dl,
182                                                 SDValue N1, SDValue N2,
183                                                 ArrayRef<int> Mask) const {
184  unsigned NumMaskElts = VT.getVectorNumElements();
185  unsigned NumDestElts = NVT.getVectorNumElements();
186  unsigned NumEltsGrowth = NumDestElts / NumMaskElts;
187
188  assert(NumEltsGrowth && "Cannot promote to vector type with fewer elts!");
189
190  if (NumEltsGrowth == 1)
191    return DAG.getVectorShuffle(NVT, dl, N1, N2, &Mask[0]);
192
193  SmallVector<int, 8> NewMask;
194  for (unsigned i = 0; i != NumMaskElts; ++i) {
195    int Idx = Mask[i];
196    for (unsigned j = 0; j != NumEltsGrowth; ++j) {
197      if (Idx < 0)
198        NewMask.push_back(-1);
199      else
200        NewMask.push_back(Idx * NumEltsGrowth + j);
201    }
202  }
203  assert(NewMask.size() == NumDestElts && "Non-integer NumEltsGrowth?");
204  assert(TLI.isShuffleMaskLegal(NewMask, NVT) && "Shuffle not legal?");
205  return DAG.getVectorShuffle(NVT, dl, N1, N2, &NewMask[0]);
206}
207
208SelectionDAGLegalize::SelectionDAGLegalize(SelectionDAG &dag)
209  : SelectionDAG::DAGUpdateListener(dag),
210    TM(dag.getTarget()), TLI(dag.getTargetLoweringInfo()),
211    DAG(dag) {
212}
213
214void SelectionDAGLegalize::LegalizeDAG() {
215  DAG.AssignTopologicalOrder();
216
217  // Visit all the nodes. We start in topological order, so that we see
218  // nodes with their original operands intact. Legalization can produce
219  // new nodes which may themselves need to be legalized. Iterate until all
220  // nodes have been legalized.
221  for (;;) {
222    bool AnyLegalized = false;
223    for (LegalizePosition = DAG.allnodes_end();
224         LegalizePosition != DAG.allnodes_begin(); ) {
225      --LegalizePosition;
226
227      SDNode *N = LegalizePosition;
228      if (LegalizedNodes.insert(N)) {
229        AnyLegalized = true;
230        LegalizeOp(N);
231      }
232    }
233    if (!AnyLegalized)
234      break;
235
236  }
237
238  // Remove dead nodes now.
239  DAG.RemoveDeadNodes();
240}
241
242/// ExpandConstantFP - Expands the ConstantFP node to an integer constant or
243/// a load from the constant pool.
244SDValue
245SelectionDAGLegalize::ExpandConstantFP(ConstantFPSDNode *CFP, bool UseCP) {
246  bool Extend = false;
247  DebugLoc dl = CFP->getDebugLoc();
248
249  // If a FP immediate is precise when represented as a float and if the
250  // target can do an extending load from float to double, we put it into
251  // the constant pool as a float, even if it's is statically typed as a
252  // double.  This shrinks FP constants and canonicalizes them for targets where
253  // an FP extending load is the same cost as a normal load (such as on the x87
254  // fp stack or PPC FP unit).
255  EVT VT = CFP->getValueType(0);
256  ConstantFP *LLVMC = const_cast<ConstantFP*>(CFP->getConstantFPValue());
257  if (!UseCP) {
258    assert((VT == MVT::f64 || VT == MVT::f32) && "Invalid type expansion");
259    return DAG.getConstant(LLVMC->getValueAPF().bitcastToAPInt(),
260                           (VT == MVT::f64) ? MVT::i64 : MVT::i32);
261  }
262
263  EVT OrigVT = VT;
264  EVT SVT = VT;
265  while (SVT != MVT::f32) {
266    SVT = (MVT::SimpleValueType)(SVT.getSimpleVT().SimpleTy - 1);
267    if (ConstantFPSDNode::isValueValidForType(SVT, CFP->getValueAPF()) &&
268        // Only do this if the target has a native EXTLOAD instruction from
269        // smaller type.
270        TLI.isLoadExtLegal(ISD::EXTLOAD, SVT) &&
271        TLI.ShouldShrinkFPConstant(OrigVT)) {
272      Type *SType = SVT.getTypeForEVT(*DAG.getContext());
273      LLVMC = cast<ConstantFP>(ConstantExpr::getFPTrunc(LLVMC, SType));
274      VT = SVT;
275      Extend = true;
276    }
277  }
278
279  SDValue CPIdx = DAG.getConstantPool(LLVMC, TLI.getPointerTy());
280  unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
281  if (Extend) {
282    SDValue Result =
283      DAG.getExtLoad(ISD::EXTLOAD, dl, OrigVT,
284                     DAG.getEntryNode(),
285                     CPIdx, MachinePointerInfo::getConstantPool(),
286                     VT, false, false, Alignment);
287    return Result;
288  }
289  SDValue Result =
290    DAG.getLoad(OrigVT, dl, DAG.getEntryNode(), CPIdx,
291                MachinePointerInfo::getConstantPool(), false, false, false,
292                Alignment);
293  return Result;
294}
295
296/// ExpandUnalignedStore - Expands an unaligned store to 2 half-size stores.
297static void ExpandUnalignedStore(StoreSDNode *ST, SelectionDAG &DAG,
298                                 const TargetLowering &TLI,
299                                 SelectionDAGLegalize *DAGLegalize) {
300  assert(ST->getAddressingMode() == ISD::UNINDEXED &&
301         "unaligned indexed stores not implemented!");
302  SDValue Chain = ST->getChain();
303  SDValue Ptr = ST->getBasePtr();
304  SDValue Val = ST->getValue();
305  EVT VT = Val.getValueType();
306  int Alignment = ST->getAlignment();
307  DebugLoc dl = ST->getDebugLoc();
308  if (ST->getMemoryVT().isFloatingPoint() ||
309      ST->getMemoryVT().isVector()) {
310    EVT intVT = EVT::getIntegerVT(*DAG.getContext(), VT.getSizeInBits());
311    if (TLI.isTypeLegal(intVT)) {
312      // Expand to a bitconvert of the value to the integer type of the
313      // same size, then a (misaligned) int store.
314      // FIXME: Does not handle truncating floating point stores!
315      SDValue Result = DAG.getNode(ISD::BITCAST, dl, intVT, Val);
316      Result = DAG.getStore(Chain, dl, Result, Ptr, ST->getPointerInfo(),
317                           ST->isVolatile(), ST->isNonTemporal(), Alignment);
318      DAGLegalize->ReplaceNode(SDValue(ST, 0), Result);
319      return;
320    }
321    // Do a (aligned) store to a stack slot, then copy from the stack slot
322    // to the final destination using (unaligned) integer loads and stores.
323    EVT StoredVT = ST->getMemoryVT();
324    EVT RegVT =
325      TLI.getRegisterType(*DAG.getContext(),
326                          EVT::getIntegerVT(*DAG.getContext(),
327                                            StoredVT.getSizeInBits()));
328    unsigned StoredBytes = StoredVT.getSizeInBits() / 8;
329    unsigned RegBytes = RegVT.getSizeInBits() / 8;
330    unsigned NumRegs = (StoredBytes + RegBytes - 1) / RegBytes;
331
332    // Make sure the stack slot is also aligned for the register type.
333    SDValue StackPtr = DAG.CreateStackTemporary(StoredVT, RegVT);
334
335    // Perform the original store, only redirected to the stack slot.
336    SDValue Store = DAG.getTruncStore(Chain, dl,
337                                      Val, StackPtr, MachinePointerInfo(),
338                                      StoredVT, false, false, 0);
339    SDValue Increment = DAG.getConstant(RegBytes, TLI.getPointerTy());
340    SmallVector<SDValue, 8> Stores;
341    unsigned Offset = 0;
342
343    // Do all but one copies using the full register width.
344    for (unsigned i = 1; i < NumRegs; i++) {
345      // Load one integer register's worth from the stack slot.
346      SDValue Load = DAG.getLoad(RegVT, dl, Store, StackPtr,
347                                 MachinePointerInfo(),
348                                 false, false, false, 0);
349      // Store it to the final location.  Remember the store.
350      Stores.push_back(DAG.getStore(Load.getValue(1), dl, Load, Ptr,
351                                  ST->getPointerInfo().getWithOffset(Offset),
352                                    ST->isVolatile(), ST->isNonTemporal(),
353                                    MinAlign(ST->getAlignment(), Offset)));
354      // Increment the pointers.
355      Offset += RegBytes;
356      StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
357                             Increment);
358      Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr, Increment);
359    }
360
361    // The last store may be partial.  Do a truncating store.  On big-endian
362    // machines this requires an extending load from the stack slot to ensure
363    // that the bits are in the right place.
364    EVT MemVT = EVT::getIntegerVT(*DAG.getContext(),
365                                  8 * (StoredBytes - Offset));
366
367    // Load from the stack slot.
368    SDValue Load = DAG.getExtLoad(ISD::EXTLOAD, dl, RegVT, Store, StackPtr,
369                                  MachinePointerInfo(),
370                                  MemVT, false, false, 0);
371
372    Stores.push_back(DAG.getTruncStore(Load.getValue(1), dl, Load, Ptr,
373                                       ST->getPointerInfo()
374                                         .getWithOffset(Offset),
375                                       MemVT, ST->isVolatile(),
376                                       ST->isNonTemporal(),
377                                       MinAlign(ST->getAlignment(), Offset)));
378    // The order of the stores doesn't matter - say it with a TokenFactor.
379    SDValue Result =
380      DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &Stores[0],
381                  Stores.size());
382    DAGLegalize->ReplaceNode(SDValue(ST, 0), Result);
383    return;
384  }
385  assert(ST->getMemoryVT().isInteger() &&
386         !ST->getMemoryVT().isVector() &&
387         "Unaligned store of unknown type.");
388  // Get the half-size VT
389  EVT NewStoredVT = ST->getMemoryVT().getHalfSizedIntegerVT(*DAG.getContext());
390  int NumBits = NewStoredVT.getSizeInBits();
391  int IncrementSize = NumBits / 8;
392
393  // Divide the stored value in two parts.
394  SDValue ShiftAmount = DAG.getConstant(NumBits,
395                                      TLI.getShiftAmountTy(Val.getValueType()));
396  SDValue Lo = Val;
397  SDValue Hi = DAG.getNode(ISD::SRL, dl, VT, Val, ShiftAmount);
398
399  // Store the two parts
400  SDValue Store1, Store2;
401  Store1 = DAG.getTruncStore(Chain, dl, TLI.isLittleEndian()?Lo:Hi, Ptr,
402                             ST->getPointerInfo(), NewStoredVT,
403                             ST->isVolatile(), ST->isNonTemporal(), Alignment);
404  Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
405                    DAG.getConstant(IncrementSize, TLI.getPointerTy()));
406  Alignment = MinAlign(Alignment, IncrementSize);
407  Store2 = DAG.getTruncStore(Chain, dl, TLI.isLittleEndian()?Hi:Lo, Ptr,
408                             ST->getPointerInfo().getWithOffset(IncrementSize),
409                             NewStoredVT, ST->isVolatile(), ST->isNonTemporal(),
410                             Alignment);
411
412  SDValue Result =
413    DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Store1, Store2);
414  DAGLegalize->ReplaceNode(SDValue(ST, 0), Result);
415}
416
417/// ExpandUnalignedLoad - Expands an unaligned load to 2 half-size loads.
418static void
419ExpandUnalignedLoad(LoadSDNode *LD, SelectionDAG &DAG,
420                    const TargetLowering &TLI,
421                    SDValue &ValResult, SDValue &ChainResult) {
422  assert(LD->getAddressingMode() == ISD::UNINDEXED &&
423         "unaligned indexed loads not implemented!");
424  SDValue Chain = LD->getChain();
425  SDValue Ptr = LD->getBasePtr();
426  EVT VT = LD->getValueType(0);
427  EVT LoadedVT = LD->getMemoryVT();
428  DebugLoc dl = LD->getDebugLoc();
429  if (VT.isFloatingPoint() || VT.isVector()) {
430    EVT intVT = EVT::getIntegerVT(*DAG.getContext(), LoadedVT.getSizeInBits());
431    if (TLI.isTypeLegal(intVT) && TLI.isTypeLegal(LoadedVT)) {
432      // Expand to a (misaligned) integer load of the same size,
433      // then bitconvert to floating point or vector.
434      SDValue newLoad = DAG.getLoad(intVT, dl, Chain, Ptr, LD->getPointerInfo(),
435                                    LD->isVolatile(),
436                                    LD->isNonTemporal(),
437                                    LD->isInvariant(), LD->getAlignment());
438      SDValue Result = DAG.getNode(ISD::BITCAST, dl, LoadedVT, newLoad);
439      if (LoadedVT != VT)
440        Result = DAG.getNode(VT.isFloatingPoint() ? ISD::FP_EXTEND :
441                             ISD::ANY_EXTEND, dl, VT, Result);
442
443      ValResult = Result;
444      ChainResult = Chain;
445      return;
446    }
447
448    // Copy the value to a (aligned) stack slot using (unaligned) integer
449    // loads and stores, then do a (aligned) load from the stack slot.
450    EVT RegVT = TLI.getRegisterType(*DAG.getContext(), intVT);
451    unsigned LoadedBytes = LoadedVT.getSizeInBits() / 8;
452    unsigned RegBytes = RegVT.getSizeInBits() / 8;
453    unsigned NumRegs = (LoadedBytes + RegBytes - 1) / RegBytes;
454
455    // Make sure the stack slot is also aligned for the register type.
456    SDValue StackBase = DAG.CreateStackTemporary(LoadedVT, RegVT);
457
458    SDValue Increment = DAG.getConstant(RegBytes, TLI.getPointerTy());
459    SmallVector<SDValue, 8> Stores;
460    SDValue StackPtr = StackBase;
461    unsigned Offset = 0;
462
463    // Do all but one copies using the full register width.
464    for (unsigned i = 1; i < NumRegs; i++) {
465      // Load one integer register's worth from the original location.
466      SDValue Load = DAG.getLoad(RegVT, dl, Chain, Ptr,
467                                 LD->getPointerInfo().getWithOffset(Offset),
468                                 LD->isVolatile(), LD->isNonTemporal(),
469                                 LD->isInvariant(),
470                                 MinAlign(LD->getAlignment(), Offset));
471      // Follow the load with a store to the stack slot.  Remember the store.
472      Stores.push_back(DAG.getStore(Load.getValue(1), dl, Load, StackPtr,
473                                    MachinePointerInfo(), false, false, 0));
474      // Increment the pointers.
475      Offset += RegBytes;
476      Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr, Increment);
477      StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
478                             Increment);
479    }
480
481    // The last copy may be partial.  Do an extending load.
482    EVT MemVT = EVT::getIntegerVT(*DAG.getContext(),
483                                  8 * (LoadedBytes - Offset));
484    SDValue Load = DAG.getExtLoad(ISD::EXTLOAD, dl, RegVT, Chain, Ptr,
485                                  LD->getPointerInfo().getWithOffset(Offset),
486                                  MemVT, LD->isVolatile(),
487                                  LD->isNonTemporal(),
488                                  MinAlign(LD->getAlignment(), Offset));
489    // Follow the load with a store to the stack slot.  Remember the store.
490    // On big-endian machines this requires a truncating store to ensure
491    // that the bits end up in the right place.
492    Stores.push_back(DAG.getTruncStore(Load.getValue(1), dl, Load, StackPtr,
493                                       MachinePointerInfo(), MemVT,
494                                       false, false, 0));
495
496    // The order of the stores doesn't matter - say it with a TokenFactor.
497    SDValue TF = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &Stores[0],
498                             Stores.size());
499
500    // Finally, perform the original load only redirected to the stack slot.
501    Load = DAG.getExtLoad(LD->getExtensionType(), dl, VT, TF, StackBase,
502                          MachinePointerInfo(), LoadedVT, false, false, 0);
503
504    // Callers expect a MERGE_VALUES node.
505    ValResult = Load;
506    ChainResult = TF;
507    return;
508  }
509  assert(LoadedVT.isInteger() && !LoadedVT.isVector() &&
510         "Unaligned load of unsupported type.");
511
512  // Compute the new VT that is half the size of the old one.  This is an
513  // integer MVT.
514  unsigned NumBits = LoadedVT.getSizeInBits();
515  EVT NewLoadedVT;
516  NewLoadedVT = EVT::getIntegerVT(*DAG.getContext(), NumBits/2);
517  NumBits >>= 1;
518
519  unsigned Alignment = LD->getAlignment();
520  unsigned IncrementSize = NumBits / 8;
521  ISD::LoadExtType HiExtType = LD->getExtensionType();
522
523  // If the original load is NON_EXTLOAD, the hi part load must be ZEXTLOAD.
524  if (HiExtType == ISD::NON_EXTLOAD)
525    HiExtType = ISD::ZEXTLOAD;
526
527  // Load the value in two parts
528  SDValue Lo, Hi;
529  if (TLI.isLittleEndian()) {
530    Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, VT, Chain, Ptr, LD->getPointerInfo(),
531                        NewLoadedVT, LD->isVolatile(),
532                        LD->isNonTemporal(), Alignment);
533    Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
534                      DAG.getConstant(IncrementSize, TLI.getPointerTy()));
535    Hi = DAG.getExtLoad(HiExtType, dl, VT, Chain, Ptr,
536                        LD->getPointerInfo().getWithOffset(IncrementSize),
537                        NewLoadedVT, LD->isVolatile(),
538                        LD->isNonTemporal(), MinAlign(Alignment,IncrementSize));
539  } else {
540    Hi = DAG.getExtLoad(HiExtType, dl, VT, Chain, Ptr, LD->getPointerInfo(),
541                        NewLoadedVT, LD->isVolatile(),
542                        LD->isNonTemporal(), Alignment);
543    Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
544                      DAG.getConstant(IncrementSize, TLI.getPointerTy()));
545    Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, VT, Chain, Ptr,
546                        LD->getPointerInfo().getWithOffset(IncrementSize),
547                        NewLoadedVT, LD->isVolatile(),
548                        LD->isNonTemporal(), MinAlign(Alignment,IncrementSize));
549  }
550
551  // aggregate the two parts
552  SDValue ShiftAmount = DAG.getConstant(NumBits,
553                                       TLI.getShiftAmountTy(Hi.getValueType()));
554  SDValue Result = DAG.getNode(ISD::SHL, dl, VT, Hi, ShiftAmount);
555  Result = DAG.getNode(ISD::OR, dl, VT, Result, Lo);
556
557  SDValue TF = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
558                             Hi.getValue(1));
559
560  ValResult = Result;
561  ChainResult = TF;
562}
563
564/// PerformInsertVectorEltInMemory - Some target cannot handle a variable
565/// insertion index for the INSERT_VECTOR_ELT instruction.  In this case, it
566/// is necessary to spill the vector being inserted into to memory, perform
567/// the insert there, and then read the result back.
568SDValue SelectionDAGLegalize::
569PerformInsertVectorEltInMemory(SDValue Vec, SDValue Val, SDValue Idx,
570                               DebugLoc dl) {
571  SDValue Tmp1 = Vec;
572  SDValue Tmp2 = Val;
573  SDValue Tmp3 = Idx;
574
575  // If the target doesn't support this, we have to spill the input vector
576  // to a temporary stack slot, update the element, then reload it.  This is
577  // badness.  We could also load the value into a vector register (either
578  // with a "move to register" or "extload into register" instruction, then
579  // permute it into place, if the idx is a constant and if the idx is
580  // supported by the target.
581  EVT VT    = Tmp1.getValueType();
582  EVT EltVT = VT.getVectorElementType();
583  EVT IdxVT = Tmp3.getValueType();
584  EVT PtrVT = TLI.getPointerTy();
585  SDValue StackPtr = DAG.CreateStackTemporary(VT);
586
587  int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
588
589  // Store the vector.
590  SDValue Ch = DAG.getStore(DAG.getEntryNode(), dl, Tmp1, StackPtr,
591                            MachinePointerInfo::getFixedStack(SPFI),
592                            false, false, 0);
593
594  // Truncate or zero extend offset to target pointer type.
595  unsigned CastOpc = IdxVT.bitsGT(PtrVT) ? ISD::TRUNCATE : ISD::ZERO_EXTEND;
596  Tmp3 = DAG.getNode(CastOpc, dl, PtrVT, Tmp3);
597  // Add the offset to the index.
598  unsigned EltSize = EltVT.getSizeInBits()/8;
599  Tmp3 = DAG.getNode(ISD::MUL, dl, IdxVT, Tmp3,DAG.getConstant(EltSize, IdxVT));
600  SDValue StackPtr2 = DAG.getNode(ISD::ADD, dl, IdxVT, Tmp3, StackPtr);
601  // Store the scalar value.
602  Ch = DAG.getTruncStore(Ch, dl, Tmp2, StackPtr2, MachinePointerInfo(), EltVT,
603                         false, false, 0);
604  // Load the updated vector.
605  return DAG.getLoad(VT, dl, Ch, StackPtr,
606                     MachinePointerInfo::getFixedStack(SPFI), false, false,
607                     false, 0);
608}
609
610
611SDValue SelectionDAGLegalize::
612ExpandINSERT_VECTOR_ELT(SDValue Vec, SDValue Val, SDValue Idx, DebugLoc dl) {
613  if (ConstantSDNode *InsertPos = dyn_cast<ConstantSDNode>(Idx)) {
614    // SCALAR_TO_VECTOR requires that the type of the value being inserted
615    // match the element type of the vector being created, except for
616    // integers in which case the inserted value can be over width.
617    EVT EltVT = Vec.getValueType().getVectorElementType();
618    if (Val.getValueType() == EltVT ||
619        (EltVT.isInteger() && Val.getValueType().bitsGE(EltVT))) {
620      SDValue ScVec = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl,
621                                  Vec.getValueType(), Val);
622
623      unsigned NumElts = Vec.getValueType().getVectorNumElements();
624      // We generate a shuffle of InVec and ScVec, so the shuffle mask
625      // should be 0,1,2,3,4,5... with the appropriate element replaced with
626      // elt 0 of the RHS.
627      SmallVector<int, 8> ShufOps;
628      for (unsigned i = 0; i != NumElts; ++i)
629        ShufOps.push_back(i != InsertPos->getZExtValue() ? i : NumElts);
630
631      return DAG.getVectorShuffle(Vec.getValueType(), dl, Vec, ScVec,
632                                  &ShufOps[0]);
633    }
634  }
635  return PerformInsertVectorEltInMemory(Vec, Val, Idx, dl);
636}
637
638SDValue SelectionDAGLegalize::OptimizeFloatStore(StoreSDNode* ST) {
639  // Turn 'store float 1.0, Ptr' -> 'store int 0x12345678, Ptr'
640  // FIXME: We shouldn't do this for TargetConstantFP's.
641  // FIXME: move this to the DAG Combiner!  Note that we can't regress due
642  // to phase ordering between legalized code and the dag combiner.  This
643  // probably means that we need to integrate dag combiner and legalizer
644  // together.
645  // We generally can't do this one for long doubles.
646  SDValue Chain = ST->getChain();
647  SDValue Ptr = ST->getBasePtr();
648  unsigned Alignment = ST->getAlignment();
649  bool isVolatile = ST->isVolatile();
650  bool isNonTemporal = ST->isNonTemporal();
651  DebugLoc dl = ST->getDebugLoc();
652  if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(ST->getValue())) {
653    if (CFP->getValueType(0) == MVT::f32 &&
654        TLI.isTypeLegal(MVT::i32)) {
655      SDValue Con = DAG.getConstant(CFP->getValueAPF().
656                                      bitcastToAPInt().zextOrTrunc(32),
657                              MVT::i32);
658      return DAG.getStore(Chain, dl, Con, Ptr, ST->getPointerInfo(),
659                          isVolatile, isNonTemporal, Alignment);
660    }
661
662    if (CFP->getValueType(0) == MVT::f64) {
663      // If this target supports 64-bit registers, do a single 64-bit store.
664      if (TLI.isTypeLegal(MVT::i64)) {
665        SDValue Con = DAG.getConstant(CFP->getValueAPF().bitcastToAPInt().
666                                  zextOrTrunc(64), MVT::i64);
667        return DAG.getStore(Chain, dl, Con, Ptr, ST->getPointerInfo(),
668                            isVolatile, isNonTemporal, Alignment);
669      }
670
671      if (TLI.isTypeLegal(MVT::i32) && !ST->isVolatile()) {
672        // Otherwise, if the target supports 32-bit registers, use 2 32-bit
673        // stores.  If the target supports neither 32- nor 64-bits, this
674        // xform is certainly not worth it.
675        const APInt &IntVal =CFP->getValueAPF().bitcastToAPInt();
676        SDValue Lo = DAG.getConstant(IntVal.trunc(32), MVT::i32);
677        SDValue Hi = DAG.getConstant(IntVal.lshr(32).trunc(32), MVT::i32);
678        if (TLI.isBigEndian()) std::swap(Lo, Hi);
679
680        Lo = DAG.getStore(Chain, dl, Lo, Ptr, ST->getPointerInfo(), isVolatile,
681                          isNonTemporal, Alignment);
682        Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
683                            DAG.getIntPtrConstant(4));
684        Hi = DAG.getStore(Chain, dl, Hi, Ptr,
685                          ST->getPointerInfo().getWithOffset(4),
686                          isVolatile, isNonTemporal, MinAlign(Alignment, 4U));
687
688        return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
689      }
690    }
691  }
692  return SDValue(0, 0);
693}
694
695void SelectionDAGLegalize::LegalizeStoreOps(SDNode *Node) {
696    StoreSDNode *ST = cast<StoreSDNode>(Node);
697    SDValue Chain = ST->getChain();
698    SDValue Ptr = ST->getBasePtr();
699    DebugLoc dl = Node->getDebugLoc();
700
701    unsigned Alignment = ST->getAlignment();
702    bool isVolatile = ST->isVolatile();
703    bool isNonTemporal = ST->isNonTemporal();
704
705    if (!ST->isTruncatingStore()) {
706      if (SDNode *OptStore = OptimizeFloatStore(ST).getNode()) {
707        ReplaceNode(ST, OptStore);
708        return;
709      }
710
711      {
712        SDValue Value = ST->getValue();
713        EVT VT = Value.getValueType();
714        switch (TLI.getOperationAction(ISD::STORE, VT)) {
715        default: llvm_unreachable("This action is not supported yet!");
716        case TargetLowering::Legal:
717          // If this is an unaligned store and the target doesn't support it,
718          // expand it.
719          if (!TLI.allowsUnalignedMemoryAccesses(ST->getMemoryVT())) {
720            Type *Ty = ST->getMemoryVT().getTypeForEVT(*DAG.getContext());
721            unsigned ABIAlignment= TLI.getDataLayout()->getABITypeAlignment(Ty);
722            if (ST->getAlignment() < ABIAlignment)
723              ExpandUnalignedStore(cast<StoreSDNode>(Node),
724                                   DAG, TLI, this);
725          }
726          break;
727        case TargetLowering::Custom: {
728          SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG);
729          if (Res.getNode())
730            ReplaceNode(SDValue(Node, 0), Res);
731          return;
732        }
733        case TargetLowering::Promote: {
734          EVT NVT = TLI.getTypeToPromoteTo(ISD::STORE, VT);
735          assert(NVT.getSizeInBits() == VT.getSizeInBits() &&
736                 "Can only promote stores to same size type");
737          Value = DAG.getNode(ISD::BITCAST, dl, NVT, Value);
738          SDValue Result =
739            DAG.getStore(Chain, dl, Value, Ptr,
740                         ST->getPointerInfo(), isVolatile,
741                         isNonTemporal, Alignment);
742          ReplaceNode(SDValue(Node, 0), Result);
743          break;
744        }
745        }
746        return;
747      }
748    } else {
749      SDValue Value = ST->getValue();
750
751      EVT StVT = ST->getMemoryVT();
752      unsigned StWidth = StVT.getSizeInBits();
753
754      if (StWidth != StVT.getStoreSizeInBits()) {
755        // Promote to a byte-sized store with upper bits zero if not
756        // storing an integral number of bytes.  For example, promote
757        // TRUNCSTORE:i1 X -> TRUNCSTORE:i8 (and X, 1)
758        EVT NVT = EVT::getIntegerVT(*DAG.getContext(),
759                                    StVT.getStoreSizeInBits());
760        Value = DAG.getZeroExtendInReg(Value, dl, StVT);
761        SDValue Result =
762          DAG.getTruncStore(Chain, dl, Value, Ptr, ST->getPointerInfo(),
763                            NVT, isVolatile, isNonTemporal, Alignment);
764        ReplaceNode(SDValue(Node, 0), Result);
765      } else if (StWidth & (StWidth - 1)) {
766        // If not storing a power-of-2 number of bits, expand as two stores.
767        assert(!StVT.isVector() && "Unsupported truncstore!");
768        unsigned RoundWidth = 1 << Log2_32(StWidth);
769        assert(RoundWidth < StWidth);
770        unsigned ExtraWidth = StWidth - RoundWidth;
771        assert(ExtraWidth < RoundWidth);
772        assert(!(RoundWidth % 8) && !(ExtraWidth % 8) &&
773               "Store size not an integral number of bytes!");
774        EVT RoundVT = EVT::getIntegerVT(*DAG.getContext(), RoundWidth);
775        EVT ExtraVT = EVT::getIntegerVT(*DAG.getContext(), ExtraWidth);
776        SDValue Lo, Hi;
777        unsigned IncrementSize;
778
779        if (TLI.isLittleEndian()) {
780          // TRUNCSTORE:i24 X -> TRUNCSTORE:i16 X, TRUNCSTORE@+2:i8 (srl X, 16)
781          // Store the bottom RoundWidth bits.
782          Lo = DAG.getTruncStore(Chain, dl, Value, Ptr, ST->getPointerInfo(),
783                                 RoundVT,
784                                 isVolatile, isNonTemporal, Alignment);
785
786          // Store the remaining ExtraWidth bits.
787          IncrementSize = RoundWidth / 8;
788          Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
789                             DAG.getIntPtrConstant(IncrementSize));
790          Hi = DAG.getNode(ISD::SRL, dl, Value.getValueType(), Value,
791                           DAG.getConstant(RoundWidth,
792                                    TLI.getShiftAmountTy(Value.getValueType())));
793          Hi = DAG.getTruncStore(Chain, dl, Hi, Ptr,
794                             ST->getPointerInfo().getWithOffset(IncrementSize),
795                                 ExtraVT, isVolatile, isNonTemporal,
796                                 MinAlign(Alignment, IncrementSize));
797        } else {
798          // Big endian - avoid unaligned stores.
799          // TRUNCSTORE:i24 X -> TRUNCSTORE:i16 (srl X, 8), TRUNCSTORE@+2:i8 X
800          // Store the top RoundWidth bits.
801          Hi = DAG.getNode(ISD::SRL, dl, Value.getValueType(), Value,
802                           DAG.getConstant(ExtraWidth,
803                                    TLI.getShiftAmountTy(Value.getValueType())));
804          Hi = DAG.getTruncStore(Chain, dl, Hi, Ptr, ST->getPointerInfo(),
805                                 RoundVT, isVolatile, isNonTemporal, Alignment);
806
807          // Store the remaining ExtraWidth bits.
808          IncrementSize = RoundWidth / 8;
809          Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
810                             DAG.getIntPtrConstant(IncrementSize));
811          Lo = DAG.getTruncStore(Chain, dl, Value, Ptr,
812                              ST->getPointerInfo().getWithOffset(IncrementSize),
813                                 ExtraVT, isVolatile, isNonTemporal,
814                                 MinAlign(Alignment, IncrementSize));
815        }
816
817        // The order of the stores doesn't matter.
818        SDValue Result = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
819        ReplaceNode(SDValue(Node, 0), Result);
820      } else {
821        switch (TLI.getTruncStoreAction(ST->getValue().getValueType(), StVT)) {
822        default: llvm_unreachable("This action is not supported yet!");
823        case TargetLowering::Legal:
824          // If this is an unaligned store and the target doesn't support it,
825          // expand it.
826          if (!TLI.allowsUnalignedMemoryAccesses(ST->getMemoryVT())) {
827            Type *Ty = ST->getMemoryVT().getTypeForEVT(*DAG.getContext());
828            unsigned ABIAlignment= TLI.getDataLayout()->getABITypeAlignment(Ty);
829            if (ST->getAlignment() < ABIAlignment)
830              ExpandUnalignedStore(cast<StoreSDNode>(Node), DAG, TLI, this);
831          }
832          break;
833        case TargetLowering::Custom: {
834          SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG);
835          if (Res.getNode())
836            ReplaceNode(SDValue(Node, 0), Res);
837          return;
838        }
839        case TargetLowering::Expand:
840          assert(!StVT.isVector() &&
841                 "Vector Stores are handled in LegalizeVectorOps");
842
843          // TRUNCSTORE:i16 i32 -> STORE i16
844          assert(TLI.isTypeLegal(StVT) &&
845                 "Do not know how to expand this store!");
846          Value = DAG.getNode(ISD::TRUNCATE, dl, StVT, Value);
847          SDValue Result =
848            DAG.getStore(Chain, dl, Value, Ptr, ST->getPointerInfo(),
849                         isVolatile, isNonTemporal, Alignment);
850          ReplaceNode(SDValue(Node, 0), Result);
851          break;
852        }
853      }
854    }
855}
856
857void SelectionDAGLegalize::LegalizeLoadOps(SDNode *Node) {
858  LoadSDNode *LD = cast<LoadSDNode>(Node);
859  SDValue Chain = LD->getChain();  // The chain.
860  SDValue Ptr = LD->getBasePtr();  // The base pointer.
861  SDValue Value;                   // The value returned by the load op.
862  DebugLoc dl = Node->getDebugLoc();
863
864  ISD::LoadExtType ExtType = LD->getExtensionType();
865  if (ExtType == ISD::NON_EXTLOAD) {
866    EVT VT = Node->getValueType(0);
867    SDValue RVal = SDValue(Node, 0);
868    SDValue RChain = SDValue(Node, 1);
869
870    switch (TLI.getOperationAction(Node->getOpcode(), VT)) {
871    default: llvm_unreachable("This action is not supported yet!");
872    case TargetLowering::Legal:
873      // If this is an unaligned load and the target doesn't support it,
874      // expand it.
875      if (!TLI.allowsUnalignedMemoryAccesses(LD->getMemoryVT())) {
876        Type *Ty = LD->getMemoryVT().getTypeForEVT(*DAG.getContext());
877        unsigned ABIAlignment =
878          TLI.getDataLayout()->getABITypeAlignment(Ty);
879        if (LD->getAlignment() < ABIAlignment){
880          ExpandUnalignedLoad(cast<LoadSDNode>(Node), DAG, TLI, RVal, RChain);
881        }
882      }
883      break;
884    case TargetLowering::Custom: {
885      SDValue Res = TLI.LowerOperation(RVal, DAG);
886      if (Res.getNode()) {
887        RVal = Res;
888        RChain = Res.getValue(1);
889      }
890      break;
891    }
892    case TargetLowering::Promote: {
893      EVT NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), VT);
894      assert(NVT.getSizeInBits() == VT.getSizeInBits() &&
895             "Can only promote loads to same size type");
896
897      SDValue Res = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getPointerInfo(),
898                         LD->isVolatile(), LD->isNonTemporal(),
899                         LD->isInvariant(), LD->getAlignment());
900      RVal = DAG.getNode(ISD::BITCAST, dl, VT, Res);
901      RChain = Res.getValue(1);
902      break;
903    }
904    }
905    if (RChain.getNode() != Node) {
906      assert(RVal.getNode() != Node && "Load must be completely replaced");
907      DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 0), RVal);
908      DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 1), RChain);
909      ReplacedNode(Node);
910    }
911    return;
912  }
913
914  EVT SrcVT = LD->getMemoryVT();
915  unsigned SrcWidth = SrcVT.getSizeInBits();
916  unsigned Alignment = LD->getAlignment();
917  bool isVolatile = LD->isVolatile();
918  bool isNonTemporal = LD->isNonTemporal();
919
920  if (SrcWidth != SrcVT.getStoreSizeInBits() &&
921      // Some targets pretend to have an i1 loading operation, and actually
922      // load an i8.  This trick is correct for ZEXTLOAD because the top 7
923      // bits are guaranteed to be zero; it helps the optimizers understand
924      // that these bits are zero.  It is also useful for EXTLOAD, since it
925      // tells the optimizers that those bits are undefined.  It would be
926      // nice to have an effective generic way of getting these benefits...
927      // Until such a way is found, don't insist on promoting i1 here.
928      (SrcVT != MVT::i1 ||
929       TLI.getLoadExtAction(ExtType, MVT::i1) == TargetLowering::Promote)) {
930    // Promote to a byte-sized load if not loading an integral number of
931    // bytes.  For example, promote EXTLOAD:i20 -> EXTLOAD:i24.
932    unsigned NewWidth = SrcVT.getStoreSizeInBits();
933    EVT NVT = EVT::getIntegerVT(*DAG.getContext(), NewWidth);
934    SDValue Ch;
935
936    // The extra bits are guaranteed to be zero, since we stored them that
937    // way.  A zext load from NVT thus automatically gives zext from SrcVT.
938
939    ISD::LoadExtType NewExtType =
940      ExtType == ISD::ZEXTLOAD ? ISD::ZEXTLOAD : ISD::EXTLOAD;
941
942    SDValue Result =
943      DAG.getExtLoad(NewExtType, dl, Node->getValueType(0),
944                     Chain, Ptr, LD->getPointerInfo(),
945                     NVT, isVolatile, isNonTemporal, Alignment);
946
947    Ch = Result.getValue(1); // The chain.
948
949    if (ExtType == ISD::SEXTLOAD)
950      // Having the top bits zero doesn't help when sign extending.
951      Result = DAG.getNode(ISD::SIGN_EXTEND_INREG, dl,
952                           Result.getValueType(),
953                           Result, DAG.getValueType(SrcVT));
954    else if (ExtType == ISD::ZEXTLOAD || NVT == Result.getValueType())
955      // All the top bits are guaranteed to be zero - inform the optimizers.
956      Result = DAG.getNode(ISD::AssertZext, dl,
957                           Result.getValueType(), Result,
958                           DAG.getValueType(SrcVT));
959
960    Value = Result;
961    Chain = Ch;
962  } else if (SrcWidth & (SrcWidth - 1)) {
963    // If not loading a power-of-2 number of bits, expand as two loads.
964    assert(!SrcVT.isVector() && "Unsupported extload!");
965    unsigned RoundWidth = 1 << Log2_32(SrcWidth);
966    assert(RoundWidth < SrcWidth);
967    unsigned ExtraWidth = SrcWidth - RoundWidth;
968    assert(ExtraWidth < RoundWidth);
969    assert(!(RoundWidth % 8) && !(ExtraWidth % 8) &&
970           "Load size not an integral number of bytes!");
971    EVT RoundVT = EVT::getIntegerVT(*DAG.getContext(), RoundWidth);
972    EVT ExtraVT = EVT::getIntegerVT(*DAG.getContext(), ExtraWidth);
973    SDValue Lo, Hi, Ch;
974    unsigned IncrementSize;
975
976    if (TLI.isLittleEndian()) {
977      // EXTLOAD:i24 -> ZEXTLOAD:i16 | (shl EXTLOAD@+2:i8, 16)
978      // Load the bottom RoundWidth bits.
979      Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, Node->getValueType(0),
980                          Chain, Ptr,
981                          LD->getPointerInfo(), RoundVT, isVolatile,
982                          isNonTemporal, Alignment);
983
984      // Load the remaining ExtraWidth bits.
985      IncrementSize = RoundWidth / 8;
986      Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
987                         DAG.getIntPtrConstant(IncrementSize));
988      Hi = DAG.getExtLoad(ExtType, dl, Node->getValueType(0), Chain, Ptr,
989                          LD->getPointerInfo().getWithOffset(IncrementSize),
990                          ExtraVT, isVolatile, isNonTemporal,
991                          MinAlign(Alignment, IncrementSize));
992
993      // Build a factor node to remember that this load is independent of
994      // the other one.
995      Ch = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
996                       Hi.getValue(1));
997
998      // Move the top bits to the right place.
999      Hi = DAG.getNode(ISD::SHL, dl, Hi.getValueType(), Hi,
1000                       DAG.getConstant(RoundWidth,
1001                                       TLI.getShiftAmountTy(Hi.getValueType())));
1002
1003      // Join the hi and lo parts.
1004      Value = DAG.getNode(ISD::OR, dl, Node->getValueType(0), Lo, Hi);
1005    } else {
1006      // Big endian - avoid unaligned loads.
1007      // EXTLOAD:i24 -> (shl EXTLOAD:i16, 8) | ZEXTLOAD@+2:i8
1008      // Load the top RoundWidth bits.
1009      Hi = DAG.getExtLoad(ExtType, dl, Node->getValueType(0), Chain, Ptr,
1010                          LD->getPointerInfo(), RoundVT, isVolatile,
1011                          isNonTemporal, Alignment);
1012
1013      // Load the remaining ExtraWidth bits.
1014      IncrementSize = RoundWidth / 8;
1015      Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
1016                         DAG.getIntPtrConstant(IncrementSize));
1017      Lo = DAG.getExtLoad(ISD::ZEXTLOAD,
1018                          dl, Node->getValueType(0), Chain, Ptr,
1019                          LD->getPointerInfo().getWithOffset(IncrementSize),
1020                          ExtraVT, isVolatile, isNonTemporal,
1021                          MinAlign(Alignment, IncrementSize));
1022
1023      // Build a factor node to remember that this load is independent of
1024      // the other one.
1025      Ch = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
1026                       Hi.getValue(1));
1027
1028      // Move the top bits to the right place.
1029      Hi = DAG.getNode(ISD::SHL, dl, Hi.getValueType(), Hi,
1030                       DAG.getConstant(ExtraWidth,
1031                                       TLI.getShiftAmountTy(Hi.getValueType())));
1032
1033      // Join the hi and lo parts.
1034      Value = DAG.getNode(ISD::OR, dl, Node->getValueType(0), Lo, Hi);
1035    }
1036
1037    Chain = Ch;
1038  } else {
1039    bool isCustom = false;
1040    switch (TLI.getLoadExtAction(ExtType, SrcVT)) {
1041    default: llvm_unreachable("This action is not supported yet!");
1042    case TargetLowering::Custom:
1043             isCustom = true;
1044             // FALLTHROUGH
1045    case TargetLowering::Legal: {
1046             Value = SDValue(Node, 0);
1047             Chain = SDValue(Node, 1);
1048
1049             if (isCustom) {
1050               SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG);
1051               if (Res.getNode()) {
1052                 Value = Res;
1053                 Chain = Res.getValue(1);
1054               }
1055             } else {
1056               // If this is an unaligned load and the target doesn't support it,
1057               // expand it.
1058               if (!TLI.allowsUnalignedMemoryAccesses(LD->getMemoryVT())) {
1059                 Type *Ty =
1060                   LD->getMemoryVT().getTypeForEVT(*DAG.getContext());
1061                 unsigned ABIAlignment =
1062                   TLI.getDataLayout()->getABITypeAlignment(Ty);
1063                 if (LD->getAlignment() < ABIAlignment){
1064                   ExpandUnalignedLoad(cast<LoadSDNode>(Node),
1065                                       DAG, TLI, Value, Chain);
1066                 }
1067               }
1068             }
1069             break;
1070    }
1071    case TargetLowering::Expand:
1072             if (!TLI.isLoadExtLegal(ISD::EXTLOAD, SrcVT) && TLI.isTypeLegal(SrcVT)) {
1073               SDValue Load = DAG.getLoad(SrcVT, dl, Chain, Ptr,
1074                                          LD->getPointerInfo(),
1075                                          LD->isVolatile(), LD->isNonTemporal(),
1076                                          LD->isInvariant(), LD->getAlignment());
1077               unsigned ExtendOp;
1078               switch (ExtType) {
1079               case ISD::EXTLOAD:
1080                 ExtendOp = (SrcVT.isFloatingPoint() ?
1081                             ISD::FP_EXTEND : ISD::ANY_EXTEND);
1082                 break;
1083               case ISD::SEXTLOAD: ExtendOp = ISD::SIGN_EXTEND; break;
1084               case ISD::ZEXTLOAD: ExtendOp = ISD::ZERO_EXTEND; break;
1085               default: llvm_unreachable("Unexpected extend load type!");
1086               }
1087               Value = DAG.getNode(ExtendOp, dl, Node->getValueType(0), Load);
1088               Chain = Load.getValue(1);
1089               break;
1090             }
1091
1092             assert(!SrcVT.isVector() &&
1093                    "Vector Loads are handled in LegalizeVectorOps");
1094
1095             // FIXME: This does not work for vectors on most targets.  Sign- and
1096             // zero-extend operations are currently folded into extending loads,
1097             // whether they are legal or not, and then we end up here without any
1098             // support for legalizing them.
1099             assert(ExtType != ISD::EXTLOAD &&
1100                    "EXTLOAD should always be supported!");
1101             // Turn the unsupported load into an EXTLOAD followed by an explicit
1102             // zero/sign extend inreg.
1103             SDValue Result = DAG.getExtLoad(ISD::EXTLOAD, dl, Node->getValueType(0),
1104                                             Chain, Ptr, LD->getPointerInfo(), SrcVT,
1105                                             LD->isVolatile(), LD->isNonTemporal(),
1106                                             LD->getAlignment());
1107             SDValue ValRes;
1108             if (ExtType == ISD::SEXTLOAD)
1109               ValRes = DAG.getNode(ISD::SIGN_EXTEND_INREG, dl,
1110                                    Result.getValueType(),
1111                                    Result, DAG.getValueType(SrcVT));
1112             else
1113               ValRes = DAG.getZeroExtendInReg(Result, dl, SrcVT.getScalarType());
1114             Value = ValRes;
1115             Chain = Result.getValue(1);
1116             break;
1117    }
1118  }
1119
1120  // Since loads produce two values, make sure to remember that we legalized
1121  // both of them.
1122  if (Chain.getNode() != Node) {
1123    assert(Value.getNode() != Node && "Load must be completely replaced");
1124    DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 0), Value);
1125    DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 1), Chain);
1126    ReplacedNode(Node);
1127  }
1128}
1129
1130/// LegalizeOp - Return a legal replacement for the given operation, with
1131/// all legal operands.
1132void SelectionDAGLegalize::LegalizeOp(SDNode *Node) {
1133  if (Node->getOpcode() == ISD::TargetConstant) // Allow illegal target nodes.
1134    return;
1135
1136  for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
1137    assert(TLI.getTypeAction(*DAG.getContext(), Node->getValueType(i)) ==
1138             TargetLowering::TypeLegal &&
1139           "Unexpected illegal type!");
1140
1141  for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i)
1142    assert((TLI.getTypeAction(*DAG.getContext(),
1143                              Node->getOperand(i).getValueType()) ==
1144              TargetLowering::TypeLegal ||
1145            Node->getOperand(i).getOpcode() == ISD::TargetConstant) &&
1146           "Unexpected illegal type!");
1147
1148  // Figure out the correct action; the way to query this varies by opcode
1149  TargetLowering::LegalizeAction Action = TargetLowering::Legal;
1150  bool SimpleFinishLegalizing = true;
1151  switch (Node->getOpcode()) {
1152  case ISD::INTRINSIC_W_CHAIN:
1153  case ISD::INTRINSIC_WO_CHAIN:
1154  case ISD::INTRINSIC_VOID:
1155  case ISD::STACKSAVE:
1156    Action = TLI.getOperationAction(Node->getOpcode(), MVT::Other);
1157    break;
1158  case ISD::VAARG:
1159    Action = TLI.getOperationAction(Node->getOpcode(),
1160                                    Node->getValueType(0));
1161    if (Action != TargetLowering::Promote)
1162      Action = TLI.getOperationAction(Node->getOpcode(), MVT::Other);
1163    break;
1164  case ISD::SINT_TO_FP:
1165  case ISD::UINT_TO_FP:
1166  case ISD::EXTRACT_VECTOR_ELT:
1167    Action = TLI.getOperationAction(Node->getOpcode(),
1168                                    Node->getOperand(0).getValueType());
1169    break;
1170  case ISD::FP_ROUND_INREG:
1171  case ISD::SIGN_EXTEND_INREG: {
1172    EVT InnerType = cast<VTSDNode>(Node->getOperand(1))->getVT();
1173    Action = TLI.getOperationAction(Node->getOpcode(), InnerType);
1174    break;
1175  }
1176  case ISD::ATOMIC_STORE: {
1177    Action = TLI.getOperationAction(Node->getOpcode(),
1178                                    Node->getOperand(2).getValueType());
1179    break;
1180  }
1181  case ISD::SELECT_CC:
1182  case ISD::SETCC:
1183  case ISD::BR_CC: {
1184    unsigned CCOperand = Node->getOpcode() == ISD::SELECT_CC ? 4 :
1185                         Node->getOpcode() == ISD::SETCC ? 2 : 1;
1186    unsigned CompareOperand = Node->getOpcode() == ISD::BR_CC ? 2 : 0;
1187    EVT OpVT = Node->getOperand(CompareOperand).getValueType();
1188    ISD::CondCode CCCode =
1189        cast<CondCodeSDNode>(Node->getOperand(CCOperand))->get();
1190    Action = TLI.getCondCodeAction(CCCode, OpVT);
1191    if (Action == TargetLowering::Legal) {
1192      if (Node->getOpcode() == ISD::SELECT_CC)
1193        Action = TLI.getOperationAction(Node->getOpcode(),
1194                                        Node->getValueType(0));
1195      else
1196        Action = TLI.getOperationAction(Node->getOpcode(), OpVT);
1197    }
1198    break;
1199  }
1200  case ISD::LOAD:
1201  case ISD::STORE:
1202    // FIXME: Model these properly.  LOAD and STORE are complicated, and
1203    // STORE expects the unlegalized operand in some cases.
1204    SimpleFinishLegalizing = false;
1205    break;
1206  case ISD::CALLSEQ_START:
1207  case ISD::CALLSEQ_END:
1208    // FIXME: This shouldn't be necessary.  These nodes have special properties
1209    // dealing with the recursive nature of legalization.  Removing this
1210    // special case should be done as part of making LegalizeDAG non-recursive.
1211    SimpleFinishLegalizing = false;
1212    break;
1213  case ISD::EXTRACT_ELEMENT:
1214  case ISD::FLT_ROUNDS_:
1215  case ISD::SADDO:
1216  case ISD::SSUBO:
1217  case ISD::UADDO:
1218  case ISD::USUBO:
1219  case ISD::SMULO:
1220  case ISD::UMULO:
1221  case ISD::FPOWI:
1222  case ISD::MERGE_VALUES:
1223  case ISD::EH_RETURN:
1224  case ISD::FRAME_TO_ARGS_OFFSET:
1225  case ISD::EH_SJLJ_SETJMP:
1226  case ISD::EH_SJLJ_LONGJMP:
1227    // These operations lie about being legal: when they claim to be legal,
1228    // they should actually be expanded.
1229    Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1230    if (Action == TargetLowering::Legal)
1231      Action = TargetLowering::Expand;
1232    break;
1233  case ISD::INIT_TRAMPOLINE:
1234  case ISD::ADJUST_TRAMPOLINE:
1235  case ISD::FRAMEADDR:
1236  case ISD::RETURNADDR:
1237    // These operations lie about being legal: when they claim to be legal,
1238    // they should actually be custom-lowered.
1239    Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1240    if (Action == TargetLowering::Legal)
1241      Action = TargetLowering::Custom;
1242    break;
1243  case ISD::DEBUGTRAP:
1244    Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1245    if (Action == TargetLowering::Expand) {
1246      // replace ISD::DEBUGTRAP with ISD::TRAP
1247      SDValue NewVal;
1248      NewVal = DAG.getNode(ISD::TRAP, Node->getDebugLoc(), Node->getVTList(),
1249                           Node->getOperand(0));
1250      ReplaceNode(Node, NewVal.getNode());
1251      LegalizeOp(NewVal.getNode());
1252      return;
1253    }
1254    break;
1255
1256  default:
1257    if (Node->getOpcode() >= ISD::BUILTIN_OP_END) {
1258      Action = TargetLowering::Legal;
1259    } else {
1260      Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1261    }
1262    break;
1263  }
1264
1265  if (SimpleFinishLegalizing) {
1266    SDNode *NewNode = Node;
1267    switch (Node->getOpcode()) {
1268    default: break;
1269    case ISD::SHL:
1270    case ISD::SRL:
1271    case ISD::SRA:
1272    case ISD::ROTL:
1273    case ISD::ROTR:
1274      // Legalizing shifts/rotates requires adjusting the shift amount
1275      // to the appropriate width.
1276      if (!Node->getOperand(1).getValueType().isVector()) {
1277        SDValue SAO =
1278          DAG.getShiftAmountOperand(Node->getOperand(0).getValueType(),
1279                                    Node->getOperand(1));
1280        HandleSDNode Handle(SAO);
1281        LegalizeOp(SAO.getNode());
1282        NewNode = DAG.UpdateNodeOperands(Node, Node->getOperand(0),
1283                                         Handle.getValue());
1284      }
1285      break;
1286    case ISD::SRL_PARTS:
1287    case ISD::SRA_PARTS:
1288    case ISD::SHL_PARTS:
1289      // Legalizing shifts/rotates requires adjusting the shift amount
1290      // to the appropriate width.
1291      if (!Node->getOperand(2).getValueType().isVector()) {
1292        SDValue SAO =
1293          DAG.getShiftAmountOperand(Node->getOperand(0).getValueType(),
1294                                    Node->getOperand(2));
1295        HandleSDNode Handle(SAO);
1296        LegalizeOp(SAO.getNode());
1297        NewNode = DAG.UpdateNodeOperands(Node, Node->getOperand(0),
1298                                         Node->getOperand(1),
1299                                         Handle.getValue());
1300      }
1301      break;
1302    }
1303
1304    if (NewNode != Node) {
1305      DAG.ReplaceAllUsesWith(Node, NewNode);
1306      for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
1307        DAG.TransferDbgValues(SDValue(Node, i), SDValue(NewNode, i));
1308      ReplacedNode(Node);
1309      Node = NewNode;
1310    }
1311    switch (Action) {
1312    case TargetLowering::Legal:
1313      return;
1314    case TargetLowering::Custom: {
1315      // FIXME: The handling for custom lowering with multiple results is
1316      // a complete mess.
1317      SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG);
1318      if (Res.getNode()) {
1319        SmallVector<SDValue, 8> ResultVals;
1320        for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i) {
1321          if (e == 1)
1322            ResultVals.push_back(Res);
1323          else
1324            ResultVals.push_back(Res.getValue(i));
1325        }
1326        if (Res.getNode() != Node || Res.getResNo() != 0) {
1327          DAG.ReplaceAllUsesWith(Node, ResultVals.data());
1328          for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
1329            DAG.TransferDbgValues(SDValue(Node, i), ResultVals[i]);
1330          ReplacedNode(Node);
1331        }
1332        return;
1333      }
1334    }
1335      // FALL THROUGH
1336    case TargetLowering::Expand:
1337      ExpandNode(Node);
1338      return;
1339    case TargetLowering::Promote:
1340      PromoteNode(Node);
1341      return;
1342    }
1343  }
1344
1345  switch (Node->getOpcode()) {
1346  default:
1347#ifndef NDEBUG
1348    dbgs() << "NODE: ";
1349    Node->dump( &DAG);
1350    dbgs() << "\n";
1351#endif
1352    llvm_unreachable("Do not know how to legalize this operator!");
1353
1354  case ISD::CALLSEQ_START:
1355  case ISD::CALLSEQ_END:
1356    break;
1357  case ISD::LOAD: {
1358    return LegalizeLoadOps(Node);
1359  }
1360  case ISD::STORE: {
1361    return LegalizeStoreOps(Node);
1362  }
1363  }
1364}
1365
1366SDValue SelectionDAGLegalize::ExpandExtractFromVectorThroughStack(SDValue Op) {
1367  SDValue Vec = Op.getOperand(0);
1368  SDValue Idx = Op.getOperand(1);
1369  DebugLoc dl = Op.getDebugLoc();
1370  // Store the value to a temporary stack slot, then LOAD the returned part.
1371  SDValue StackPtr = DAG.CreateStackTemporary(Vec.getValueType());
1372  SDValue Ch = DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr,
1373                            MachinePointerInfo(), false, false, 0);
1374
1375  // Add the offset to the index.
1376  unsigned EltSize =
1377      Vec.getValueType().getVectorElementType().getSizeInBits()/8;
1378  Idx = DAG.getNode(ISD::MUL, dl, Idx.getValueType(), Idx,
1379                    DAG.getConstant(EltSize, Idx.getValueType()));
1380
1381  if (Idx.getValueType().bitsGT(TLI.getPointerTy()))
1382    Idx = DAG.getNode(ISD::TRUNCATE, dl, TLI.getPointerTy(), Idx);
1383  else
1384    Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
1385
1386  StackPtr = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, StackPtr);
1387
1388  if (Op.getValueType().isVector())
1389    return DAG.getLoad(Op.getValueType(), dl, Ch, StackPtr,MachinePointerInfo(),
1390                       false, false, false, 0);
1391  return DAG.getExtLoad(ISD::EXTLOAD, dl, Op.getValueType(), Ch, StackPtr,
1392                        MachinePointerInfo(),
1393                        Vec.getValueType().getVectorElementType(),
1394                        false, false, 0);
1395}
1396
1397SDValue SelectionDAGLegalize::ExpandInsertToVectorThroughStack(SDValue Op) {
1398  assert(Op.getValueType().isVector() && "Non-vector insert subvector!");
1399
1400  SDValue Vec  = Op.getOperand(0);
1401  SDValue Part = Op.getOperand(1);
1402  SDValue Idx  = Op.getOperand(2);
1403  DebugLoc dl  = Op.getDebugLoc();
1404
1405  // Store the value to a temporary stack slot, then LOAD the returned part.
1406
1407  SDValue StackPtr = DAG.CreateStackTemporary(Vec.getValueType());
1408  int FI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
1409  MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(FI);
1410
1411  // First store the whole vector.
1412  SDValue Ch = DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr, PtrInfo,
1413                            false, false, 0);
1414
1415  // Then store the inserted part.
1416
1417  // Add the offset to the index.
1418  unsigned EltSize =
1419      Vec.getValueType().getVectorElementType().getSizeInBits()/8;
1420
1421  Idx = DAG.getNode(ISD::MUL, dl, Idx.getValueType(), Idx,
1422                    DAG.getConstant(EltSize, Idx.getValueType()));
1423
1424  if (Idx.getValueType().bitsGT(TLI.getPointerTy()))
1425    Idx = DAG.getNode(ISD::TRUNCATE, dl, TLI.getPointerTy(), Idx);
1426  else
1427    Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
1428
1429  SDValue SubStackPtr = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx,
1430                                    StackPtr);
1431
1432  // Store the subvector.
1433  Ch = DAG.getStore(DAG.getEntryNode(), dl, Part, SubStackPtr,
1434                    MachinePointerInfo(), false, false, 0);
1435
1436  // Finally, load the updated vector.
1437  return DAG.getLoad(Op.getValueType(), dl, Ch, StackPtr, PtrInfo,
1438                     false, false, false, 0);
1439}
1440
1441SDValue SelectionDAGLegalize::ExpandVectorBuildThroughStack(SDNode* Node) {
1442  // We can't handle this case efficiently.  Allocate a sufficiently
1443  // aligned object on the stack, store each element into it, then load
1444  // the result as a vector.
1445  // Create the stack frame object.
1446  EVT VT = Node->getValueType(0);
1447  EVT EltVT = VT.getVectorElementType();
1448  DebugLoc dl = Node->getDebugLoc();
1449  SDValue FIPtr = DAG.CreateStackTemporary(VT);
1450  int FI = cast<FrameIndexSDNode>(FIPtr.getNode())->getIndex();
1451  MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(FI);
1452
1453  // Emit a store of each element to the stack slot.
1454  SmallVector<SDValue, 8> Stores;
1455  unsigned TypeByteSize = EltVT.getSizeInBits() / 8;
1456  // Store (in the right endianness) the elements to memory.
1457  for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
1458    // Ignore undef elements.
1459    if (Node->getOperand(i).getOpcode() == ISD::UNDEF) continue;
1460
1461    unsigned Offset = TypeByteSize*i;
1462
1463    SDValue Idx = DAG.getConstant(Offset, FIPtr.getValueType());
1464    Idx = DAG.getNode(ISD::ADD, dl, FIPtr.getValueType(), FIPtr, Idx);
1465
1466    // If the destination vector element type is narrower than the source
1467    // element type, only store the bits necessary.
1468    if (EltVT.bitsLT(Node->getOperand(i).getValueType().getScalarType())) {
1469      Stores.push_back(DAG.getTruncStore(DAG.getEntryNode(), dl,
1470                                         Node->getOperand(i), Idx,
1471                                         PtrInfo.getWithOffset(Offset),
1472                                         EltVT, false, false, 0));
1473    } else
1474      Stores.push_back(DAG.getStore(DAG.getEntryNode(), dl,
1475                                    Node->getOperand(i), Idx,
1476                                    PtrInfo.getWithOffset(Offset),
1477                                    false, false, 0));
1478  }
1479
1480  SDValue StoreChain;
1481  if (!Stores.empty())    // Not all undef elements?
1482    StoreChain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
1483                             &Stores[0], Stores.size());
1484  else
1485    StoreChain = DAG.getEntryNode();
1486
1487  // Result is a load from the stack slot.
1488  return DAG.getLoad(VT, dl, StoreChain, FIPtr, PtrInfo,
1489                     false, false, false, 0);
1490}
1491
1492SDValue SelectionDAGLegalize::ExpandFCOPYSIGN(SDNode* Node) {
1493  DebugLoc dl = Node->getDebugLoc();
1494  SDValue Tmp1 = Node->getOperand(0);
1495  SDValue Tmp2 = Node->getOperand(1);
1496
1497  // Get the sign bit of the RHS.  First obtain a value that has the same
1498  // sign as the sign bit, i.e. negative if and only if the sign bit is 1.
1499  SDValue SignBit;
1500  EVT FloatVT = Tmp2.getValueType();
1501  EVT IVT = EVT::getIntegerVT(*DAG.getContext(), FloatVT.getSizeInBits());
1502  if (TLI.isTypeLegal(IVT)) {
1503    // Convert to an integer with the same sign bit.
1504    SignBit = DAG.getNode(ISD::BITCAST, dl, IVT, Tmp2);
1505  } else {
1506    // Store the float to memory, then load the sign part out as an integer.
1507    MVT LoadTy = TLI.getPointerTy();
1508    // First create a temporary that is aligned for both the load and store.
1509    SDValue StackPtr = DAG.CreateStackTemporary(FloatVT, LoadTy);
1510    // Then store the float to it.
1511    SDValue Ch =
1512      DAG.getStore(DAG.getEntryNode(), dl, Tmp2, StackPtr, MachinePointerInfo(),
1513                   false, false, 0);
1514    if (TLI.isBigEndian()) {
1515      assert(FloatVT.isByteSized() && "Unsupported floating point type!");
1516      // Load out a legal integer with the same sign bit as the float.
1517      SignBit = DAG.getLoad(LoadTy, dl, Ch, StackPtr, MachinePointerInfo(),
1518                            false, false, false, 0);
1519    } else { // Little endian
1520      SDValue LoadPtr = StackPtr;
1521      // The float may be wider than the integer we are going to load.  Advance
1522      // the pointer so that the loaded integer will contain the sign bit.
1523      unsigned Strides = (FloatVT.getSizeInBits()-1)/LoadTy.getSizeInBits();
1524      unsigned ByteOffset = (Strides * LoadTy.getSizeInBits()) / 8;
1525      LoadPtr = DAG.getNode(ISD::ADD, dl, LoadPtr.getValueType(),
1526                            LoadPtr, DAG.getIntPtrConstant(ByteOffset));
1527      // Load a legal integer containing the sign bit.
1528      SignBit = DAG.getLoad(LoadTy, dl, Ch, LoadPtr, MachinePointerInfo(),
1529                            false, false, false, 0);
1530      // Move the sign bit to the top bit of the loaded integer.
1531      unsigned BitShift = LoadTy.getSizeInBits() -
1532        (FloatVT.getSizeInBits() - 8 * ByteOffset);
1533      assert(BitShift < LoadTy.getSizeInBits() && "Pointer advanced wrong?");
1534      if (BitShift)
1535        SignBit = DAG.getNode(ISD::SHL, dl, LoadTy, SignBit,
1536                              DAG.getConstant(BitShift,
1537                                 TLI.getShiftAmountTy(SignBit.getValueType())));
1538    }
1539  }
1540  // Now get the sign bit proper, by seeing whether the value is negative.
1541  SignBit = DAG.getSetCC(dl, TLI.getSetCCResultType(SignBit.getValueType()),
1542                         SignBit, DAG.getConstant(0, SignBit.getValueType()),
1543                         ISD::SETLT);
1544  // Get the absolute value of the result.
1545  SDValue AbsVal = DAG.getNode(ISD::FABS, dl, Tmp1.getValueType(), Tmp1);
1546  // Select between the nabs and abs value based on the sign bit of
1547  // the input.
1548  return DAG.getNode(ISD::SELECT, dl, AbsVal.getValueType(), SignBit,
1549                     DAG.getNode(ISD::FNEG, dl, AbsVal.getValueType(), AbsVal),
1550                     AbsVal);
1551}
1552
1553void SelectionDAGLegalize::ExpandDYNAMIC_STACKALLOC(SDNode* Node,
1554                                           SmallVectorImpl<SDValue> &Results) {
1555  unsigned SPReg = TLI.getStackPointerRegisterToSaveRestore();
1556  assert(SPReg && "Target cannot require DYNAMIC_STACKALLOC expansion and"
1557          " not tell us which reg is the stack pointer!");
1558  DebugLoc dl = Node->getDebugLoc();
1559  EVT VT = Node->getValueType(0);
1560  SDValue Tmp1 = SDValue(Node, 0);
1561  SDValue Tmp2 = SDValue(Node, 1);
1562  SDValue Tmp3 = Node->getOperand(2);
1563  SDValue Chain = Tmp1.getOperand(0);
1564
1565  // Chain the dynamic stack allocation so that it doesn't modify the stack
1566  // pointer when other instructions are using the stack.
1567  Chain = DAG.getCALLSEQ_START(Chain, DAG.getIntPtrConstant(0, true));
1568
1569  SDValue Size  = Tmp2.getOperand(1);
1570  SDValue SP = DAG.getCopyFromReg(Chain, dl, SPReg, VT);
1571  Chain = SP.getValue(1);
1572  unsigned Align = cast<ConstantSDNode>(Tmp3)->getZExtValue();
1573  unsigned StackAlign = TM.getFrameLowering()->getStackAlignment();
1574  if (Align > StackAlign)
1575    SP = DAG.getNode(ISD::AND, dl, VT, SP,
1576                      DAG.getConstant(-(uint64_t)Align, VT));
1577  Tmp1 = DAG.getNode(ISD::SUB, dl, VT, SP, Size);       // Value
1578  Chain = DAG.getCopyToReg(Chain, dl, SPReg, Tmp1);     // Output chain
1579
1580  Tmp2 = DAG.getCALLSEQ_END(Chain,  DAG.getIntPtrConstant(0, true),
1581                            DAG.getIntPtrConstant(0, true), SDValue());
1582
1583  Results.push_back(Tmp1);
1584  Results.push_back(Tmp2);
1585}
1586
1587/// LegalizeSetCCCondCode - Legalize a SETCC with given LHS and RHS and
1588/// condition code CC on the current target. This routine expands SETCC with
1589/// illegal condition code into AND / OR of multiple SETCC values.
1590void SelectionDAGLegalize::LegalizeSetCCCondCode(EVT VT,
1591                                                 SDValue &LHS, SDValue &RHS,
1592                                                 SDValue &CC,
1593                                                 DebugLoc dl) {
1594  EVT OpVT = LHS.getValueType();
1595  ISD::CondCode CCCode = cast<CondCodeSDNode>(CC)->get();
1596  switch (TLI.getCondCodeAction(CCCode, OpVT)) {
1597  default: llvm_unreachable("Unknown condition code action!");
1598  case TargetLowering::Legal:
1599    // Nothing to do.
1600    break;
1601  case TargetLowering::Expand: {
1602    ISD::CondCode CC1 = ISD::SETCC_INVALID, CC2 = ISD::SETCC_INVALID;
1603    ISD::CondCode InvCC = ISD::SETCC_INVALID;
1604    unsigned Opc = 0;
1605    switch (CCCode) {
1606    default: llvm_unreachable("Don't know how to expand this condition!");
1607    case ISD::SETO:
1608        assert(TLI.getCondCodeAction(ISD::SETOEQ, OpVT)
1609            == TargetLowering::Legal
1610            && "If SETO is expanded, SETOEQ must be legal!");
1611        CC1 = ISD::SETOEQ; CC2 = ISD::SETOEQ; Opc = ISD::AND; break;
1612    case ISD::SETUO:
1613        assert(TLI.getCondCodeAction(ISD::SETUNE, OpVT)
1614            == TargetLowering::Legal
1615            && "If SETUO is expanded, SETUNE must be legal!");
1616        CC1 = ISD::SETUNE; CC2 = ISD::SETUNE; Opc = ISD::OR;  break;
1617    case ISD::SETOEQ:
1618    case ISD::SETOGT:
1619    case ISD::SETOGE:
1620    case ISD::SETOLT:
1621    case ISD::SETOLE:
1622    case ISD::SETONE:
1623    case ISD::SETUEQ:
1624    case ISD::SETUNE:
1625    case ISD::SETUGT:
1626    case ISD::SETUGE:
1627    case ISD::SETULT:
1628    case ISD::SETULE:
1629        // If we are floating point, assign and break, otherwise fall through.
1630        if (!OpVT.isInteger()) {
1631          // We can use the 4th bit to tell if we are the unordered
1632          // or ordered version of the opcode.
1633          CC2 = ((unsigned)CCCode & 0x8U) ? ISD::SETUO : ISD::SETO;
1634          Opc = ((unsigned)CCCode & 0x8U) ? ISD::OR : ISD::AND;
1635          CC1 = (ISD::CondCode)(((int)CCCode & 0x7) | 0x10);
1636          break;
1637        }
1638        // Fallthrough if we are unsigned integer.
1639    case ISD::SETLE:
1640    case ISD::SETGT:
1641    case ISD::SETGE:
1642    case ISD::SETLT:
1643    case ISD::SETNE:
1644    case ISD::SETEQ:
1645      InvCC = ISD::getSetCCSwappedOperands(CCCode);
1646      if (TLI.getCondCodeAction(InvCC, OpVT) == TargetLowering::Expand) {
1647        // We only support using the inverted operation and not a
1648        // different manner of supporting expanding these cases.
1649        llvm_unreachable("Don't know how to expand this condition!");
1650      }
1651      LHS = DAG.getSetCC(dl, VT, RHS, LHS, InvCC);
1652      RHS = SDValue();
1653      CC = SDValue();
1654      return;
1655    }
1656
1657    SDValue SetCC1, SetCC2;
1658    if (CCCode != ISD::SETO && CCCode != ISD::SETUO) {
1659      // If we aren't the ordered or unorder operation,
1660      // then the pattern is (LHS CC1 RHS) Opc (LHS CC2 RHS).
1661      SetCC1 = DAG.getSetCC(dl, VT, LHS, RHS, CC1);
1662      SetCC2 = DAG.getSetCC(dl, VT, LHS, RHS, CC2);
1663    } else {
1664      // Otherwise, the pattern is (LHS CC1 LHS) Opc (RHS CC2 RHS)
1665      SetCC1 = DAG.getSetCC(dl, VT, LHS, LHS, CC1);
1666      SetCC2 = DAG.getSetCC(dl, VT, RHS, RHS, CC2);
1667    }
1668    LHS = DAG.getNode(Opc, dl, VT, SetCC1, SetCC2);
1669    RHS = SDValue();
1670    CC  = SDValue();
1671    break;
1672  }
1673  }
1674}
1675
1676/// EmitStackConvert - Emit a store/load combination to the stack.  This stores
1677/// SrcOp to a stack slot of type SlotVT, truncating it if needed.  It then does
1678/// a load from the stack slot to DestVT, extending it if needed.
1679/// The resultant code need not be legal.
1680SDValue SelectionDAGLegalize::EmitStackConvert(SDValue SrcOp,
1681                                               EVT SlotVT,
1682                                               EVT DestVT,
1683                                               DebugLoc dl) {
1684  // Create the stack frame object.
1685  unsigned SrcAlign =
1686    TLI.getDataLayout()->getPrefTypeAlignment(SrcOp.getValueType().
1687                                              getTypeForEVT(*DAG.getContext()));
1688  SDValue FIPtr = DAG.CreateStackTemporary(SlotVT, SrcAlign);
1689
1690  FrameIndexSDNode *StackPtrFI = cast<FrameIndexSDNode>(FIPtr);
1691  int SPFI = StackPtrFI->getIndex();
1692  MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(SPFI);
1693
1694  unsigned SrcSize = SrcOp.getValueType().getSizeInBits();
1695  unsigned SlotSize = SlotVT.getSizeInBits();
1696  unsigned DestSize = DestVT.getSizeInBits();
1697  Type *DestType = DestVT.getTypeForEVT(*DAG.getContext());
1698  unsigned DestAlign = TLI.getDataLayout()->getPrefTypeAlignment(DestType);
1699
1700  // Emit a store to the stack slot.  Use a truncstore if the input value is
1701  // later than DestVT.
1702  SDValue Store;
1703
1704  if (SrcSize > SlotSize)
1705    Store = DAG.getTruncStore(DAG.getEntryNode(), dl, SrcOp, FIPtr,
1706                              PtrInfo, SlotVT, false, false, SrcAlign);
1707  else {
1708    assert(SrcSize == SlotSize && "Invalid store");
1709    Store = DAG.getStore(DAG.getEntryNode(), dl, SrcOp, FIPtr,
1710                         PtrInfo, false, false, SrcAlign);
1711  }
1712
1713  // Result is a load from the stack slot.
1714  if (SlotSize == DestSize)
1715    return DAG.getLoad(DestVT, dl, Store, FIPtr, PtrInfo,
1716                       false, false, false, DestAlign);
1717
1718  assert(SlotSize < DestSize && "Unknown extension!");
1719  return DAG.getExtLoad(ISD::EXTLOAD, dl, DestVT, Store, FIPtr,
1720                        PtrInfo, SlotVT, false, false, DestAlign);
1721}
1722
1723SDValue SelectionDAGLegalize::ExpandSCALAR_TO_VECTOR(SDNode *Node) {
1724  DebugLoc dl = Node->getDebugLoc();
1725  // Create a vector sized/aligned stack slot, store the value to element #0,
1726  // then load the whole vector back out.
1727  SDValue StackPtr = DAG.CreateStackTemporary(Node->getValueType(0));
1728
1729  FrameIndexSDNode *StackPtrFI = cast<FrameIndexSDNode>(StackPtr);
1730  int SPFI = StackPtrFI->getIndex();
1731
1732  SDValue Ch = DAG.getTruncStore(DAG.getEntryNode(), dl, Node->getOperand(0),
1733                                 StackPtr,
1734                                 MachinePointerInfo::getFixedStack(SPFI),
1735                                 Node->getValueType(0).getVectorElementType(),
1736                                 false, false, 0);
1737  return DAG.getLoad(Node->getValueType(0), dl, Ch, StackPtr,
1738                     MachinePointerInfo::getFixedStack(SPFI),
1739                     false, false, false, 0);
1740}
1741
1742
1743/// ExpandBUILD_VECTOR - Expand a BUILD_VECTOR node on targets that don't
1744/// support the operation, but do support the resultant vector type.
1745SDValue SelectionDAGLegalize::ExpandBUILD_VECTOR(SDNode *Node) {
1746  unsigned NumElems = Node->getNumOperands();
1747  SDValue Value1, Value2;
1748  DebugLoc dl = Node->getDebugLoc();
1749  EVT VT = Node->getValueType(0);
1750  EVT OpVT = Node->getOperand(0).getValueType();
1751  EVT EltVT = VT.getVectorElementType();
1752
1753  // If the only non-undef value is the low element, turn this into a
1754  // SCALAR_TO_VECTOR node.  If this is { X, X, X, X }, determine X.
1755  bool isOnlyLowElement = true;
1756  bool MoreThanTwoValues = false;
1757  bool isConstant = true;
1758  for (unsigned i = 0; i < NumElems; ++i) {
1759    SDValue V = Node->getOperand(i);
1760    if (V.getOpcode() == ISD::UNDEF)
1761      continue;
1762    if (i > 0)
1763      isOnlyLowElement = false;
1764    if (!isa<ConstantFPSDNode>(V) && !isa<ConstantSDNode>(V))
1765      isConstant = false;
1766
1767    if (!Value1.getNode()) {
1768      Value1 = V;
1769    } else if (!Value2.getNode()) {
1770      if (V != Value1)
1771        Value2 = V;
1772    } else if (V != Value1 && V != Value2) {
1773      MoreThanTwoValues = true;
1774    }
1775  }
1776
1777  if (!Value1.getNode())
1778    return DAG.getUNDEF(VT);
1779
1780  if (isOnlyLowElement)
1781    return DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Node->getOperand(0));
1782
1783  // If all elements are constants, create a load from the constant pool.
1784  if (isConstant) {
1785    SmallVector<Constant*, 16> CV;
1786    for (unsigned i = 0, e = NumElems; i != e; ++i) {
1787      if (ConstantFPSDNode *V =
1788          dyn_cast<ConstantFPSDNode>(Node->getOperand(i))) {
1789        CV.push_back(const_cast<ConstantFP *>(V->getConstantFPValue()));
1790      } else if (ConstantSDNode *V =
1791                 dyn_cast<ConstantSDNode>(Node->getOperand(i))) {
1792        if (OpVT==EltVT)
1793          CV.push_back(const_cast<ConstantInt *>(V->getConstantIntValue()));
1794        else {
1795          // If OpVT and EltVT don't match, EltVT is not legal and the
1796          // element values have been promoted/truncated earlier.  Undo this;
1797          // we don't want a v16i8 to become a v16i32 for example.
1798          const ConstantInt *CI = V->getConstantIntValue();
1799          CV.push_back(ConstantInt::get(EltVT.getTypeForEVT(*DAG.getContext()),
1800                                        CI->getZExtValue()));
1801        }
1802      } else {
1803        assert(Node->getOperand(i).getOpcode() == ISD::UNDEF);
1804        Type *OpNTy = EltVT.getTypeForEVT(*DAG.getContext());
1805        CV.push_back(UndefValue::get(OpNTy));
1806      }
1807    }
1808    Constant *CP = ConstantVector::get(CV);
1809    SDValue CPIdx = DAG.getConstantPool(CP, TLI.getPointerTy());
1810    unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
1811    return DAG.getLoad(VT, dl, DAG.getEntryNode(), CPIdx,
1812                       MachinePointerInfo::getConstantPool(),
1813                       false, false, false, Alignment);
1814  }
1815
1816  if (!MoreThanTwoValues) {
1817    SmallVector<int, 8> ShuffleVec(NumElems, -1);
1818    for (unsigned i = 0; i < NumElems; ++i) {
1819      SDValue V = Node->getOperand(i);
1820      if (V.getOpcode() == ISD::UNDEF)
1821        continue;
1822      ShuffleVec[i] = V == Value1 ? 0 : NumElems;
1823    }
1824    if (TLI.isShuffleMaskLegal(ShuffleVec, Node->getValueType(0))) {
1825      // Get the splatted value into the low element of a vector register.
1826      SDValue Vec1 = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Value1);
1827      SDValue Vec2;
1828      if (Value2.getNode())
1829        Vec2 = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Value2);
1830      else
1831        Vec2 = DAG.getUNDEF(VT);
1832
1833      // Return shuffle(LowValVec, undef, <0,0,0,0>)
1834      return DAG.getVectorShuffle(VT, dl, Vec1, Vec2, ShuffleVec.data());
1835    }
1836  }
1837
1838  // Otherwise, we can't handle this case efficiently.
1839  return ExpandVectorBuildThroughStack(Node);
1840}
1841
1842// ExpandLibCall - Expand a node into a call to a libcall.  If the result value
1843// does not fit into a register, return the lo part and set the hi part to the
1844// by-reg argument.  If it does fit into a single register, return the result
1845// and leave the Hi part unset.
1846SDValue SelectionDAGLegalize::ExpandLibCall(RTLIB::Libcall LC, SDNode *Node,
1847                                            bool isSigned) {
1848  TargetLowering::ArgListTy Args;
1849  TargetLowering::ArgListEntry Entry;
1850  for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
1851    EVT ArgVT = Node->getOperand(i).getValueType();
1852    Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
1853    Entry.Node = Node->getOperand(i); Entry.Ty = ArgTy;
1854    Entry.isSExt = isSigned;
1855    Entry.isZExt = !isSigned;
1856    Args.push_back(Entry);
1857  }
1858  SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
1859                                         TLI.getPointerTy());
1860
1861  Type *RetTy = Node->getValueType(0).getTypeForEVT(*DAG.getContext());
1862
1863  // By default, the input chain to this libcall is the entry node of the
1864  // function. If the libcall is going to be emitted as a tail call then
1865  // TLI.isUsedByReturnOnly will change it to the right chain if the return
1866  // node which is being folded has a non-entry input chain.
1867  SDValue InChain = DAG.getEntryNode();
1868
1869  // isTailCall may be true since the callee does not reference caller stack
1870  // frame. Check if it's in the right position.
1871  SDValue TCChain = InChain;
1872  bool isTailCall = isInTailCallPosition(DAG, Node, TCChain, TLI);
1873  if (isTailCall)
1874    InChain = TCChain;
1875
1876  TargetLowering::
1877  CallLoweringInfo CLI(InChain, RetTy, isSigned, !isSigned, false, false,
1878                    0, TLI.getLibcallCallingConv(LC), isTailCall,
1879                    /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
1880                    Callee, Args, DAG, Node->getDebugLoc());
1881  std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI);
1882
1883
1884  if (!CallInfo.second.getNode())
1885    // It's a tailcall, return the chain (which is the DAG root).
1886    return DAG.getRoot();
1887
1888  return CallInfo.first;
1889}
1890
1891/// ExpandLibCall - Generate a libcall taking the given operands as arguments
1892/// and returning a result of type RetVT.
1893SDValue SelectionDAGLegalize::ExpandLibCall(RTLIB::Libcall LC, EVT RetVT,
1894                                            const SDValue *Ops, unsigned NumOps,
1895                                            bool isSigned, DebugLoc dl) {
1896  TargetLowering::ArgListTy Args;
1897  Args.reserve(NumOps);
1898
1899  TargetLowering::ArgListEntry Entry;
1900  for (unsigned i = 0; i != NumOps; ++i) {
1901    Entry.Node = Ops[i];
1902    Entry.Ty = Entry.Node.getValueType().getTypeForEVT(*DAG.getContext());
1903    Entry.isSExt = isSigned;
1904    Entry.isZExt = !isSigned;
1905    Args.push_back(Entry);
1906  }
1907  SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
1908                                         TLI.getPointerTy());
1909
1910  Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
1911  TargetLowering::
1912  CallLoweringInfo CLI(DAG.getEntryNode(), RetTy, isSigned, !isSigned, false,
1913                       false, 0, TLI.getLibcallCallingConv(LC),
1914                       /*isTailCall=*/false,
1915                  /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
1916                  Callee, Args, DAG, dl);
1917  std::pair<SDValue,SDValue> CallInfo = TLI.LowerCallTo(CLI);
1918
1919  return CallInfo.first;
1920}
1921
1922// ExpandChainLibCall - Expand a node into a call to a libcall. Similar to
1923// ExpandLibCall except that the first operand is the in-chain.
1924std::pair<SDValue, SDValue>
1925SelectionDAGLegalize::ExpandChainLibCall(RTLIB::Libcall LC,
1926                                         SDNode *Node,
1927                                         bool isSigned) {
1928  SDValue InChain = Node->getOperand(0);
1929
1930  TargetLowering::ArgListTy Args;
1931  TargetLowering::ArgListEntry Entry;
1932  for (unsigned i = 1, e = Node->getNumOperands(); i != e; ++i) {
1933    EVT ArgVT = Node->getOperand(i).getValueType();
1934    Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
1935    Entry.Node = Node->getOperand(i);
1936    Entry.Ty = ArgTy;
1937    Entry.isSExt = isSigned;
1938    Entry.isZExt = !isSigned;
1939    Args.push_back(Entry);
1940  }
1941  SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
1942                                         TLI.getPointerTy());
1943
1944  Type *RetTy = Node->getValueType(0).getTypeForEVT(*DAG.getContext());
1945  TargetLowering::
1946  CallLoweringInfo CLI(InChain, RetTy, isSigned, !isSigned, false, false,
1947                    0, TLI.getLibcallCallingConv(LC), /*isTailCall=*/false,
1948                    /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
1949                    Callee, Args, DAG, Node->getDebugLoc());
1950  std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI);
1951
1952  return CallInfo;
1953}
1954
1955SDValue SelectionDAGLegalize::ExpandFPLibCall(SDNode* Node,
1956                                              RTLIB::Libcall Call_F32,
1957                                              RTLIB::Libcall Call_F64,
1958                                              RTLIB::Libcall Call_F80,
1959                                              RTLIB::Libcall Call_PPCF128) {
1960  RTLIB::Libcall LC;
1961  switch (Node->getValueType(0).getSimpleVT().SimpleTy) {
1962  default: llvm_unreachable("Unexpected request for libcall!");
1963  case MVT::f32: LC = Call_F32; break;
1964  case MVT::f64: LC = Call_F64; break;
1965  case MVT::f80: LC = Call_F80; break;
1966  case MVT::ppcf128: LC = Call_PPCF128; break;
1967  }
1968  return ExpandLibCall(LC, Node, false);
1969}
1970
1971SDValue SelectionDAGLegalize::ExpandIntLibCall(SDNode* Node, bool isSigned,
1972                                               RTLIB::Libcall Call_I8,
1973                                               RTLIB::Libcall Call_I16,
1974                                               RTLIB::Libcall Call_I32,
1975                                               RTLIB::Libcall Call_I64,
1976                                               RTLIB::Libcall Call_I128) {
1977  RTLIB::Libcall LC;
1978  switch (Node->getValueType(0).getSimpleVT().SimpleTy) {
1979  default: llvm_unreachable("Unexpected request for libcall!");
1980  case MVT::i8:   LC = Call_I8; break;
1981  case MVT::i16:  LC = Call_I16; break;
1982  case MVT::i32:  LC = Call_I32; break;
1983  case MVT::i64:  LC = Call_I64; break;
1984  case MVT::i128: LC = Call_I128; break;
1985  }
1986  return ExpandLibCall(LC, Node, isSigned);
1987}
1988
1989/// isDivRemLibcallAvailable - Return true if divmod libcall is available.
1990static bool isDivRemLibcallAvailable(SDNode *Node, bool isSigned,
1991                                     const TargetLowering &TLI) {
1992  RTLIB::Libcall LC;
1993  switch (Node->getValueType(0).getSimpleVT().SimpleTy) {
1994  default: llvm_unreachable("Unexpected request for libcall!");
1995  case MVT::i8:   LC= isSigned ? RTLIB::SDIVREM_I8  : RTLIB::UDIVREM_I8;  break;
1996  case MVT::i16:  LC= isSigned ? RTLIB::SDIVREM_I16 : RTLIB::UDIVREM_I16; break;
1997  case MVT::i32:  LC= isSigned ? RTLIB::SDIVREM_I32 : RTLIB::UDIVREM_I32; break;
1998  case MVT::i64:  LC= isSigned ? RTLIB::SDIVREM_I64 : RTLIB::UDIVREM_I64; break;
1999  case MVT::i128: LC= isSigned ? RTLIB::SDIVREM_I128:RTLIB::UDIVREM_I128; break;
2000  }
2001
2002  return TLI.getLibcallName(LC) != 0;
2003}
2004
2005/// useDivRem - Only issue divrem libcall if both quotient and remainder are
2006/// needed.
2007static bool useDivRem(SDNode *Node, bool isSigned, bool isDIV) {
2008  // The other use might have been replaced with a divrem already.
2009  unsigned DivRemOpc = isSigned ? ISD::SDIVREM : ISD::UDIVREM;
2010  unsigned OtherOpcode = 0;
2011  if (isSigned)
2012    OtherOpcode = isDIV ? ISD::SREM : ISD::SDIV;
2013  else
2014    OtherOpcode = isDIV ? ISD::UREM : ISD::UDIV;
2015
2016  SDValue Op0 = Node->getOperand(0);
2017  SDValue Op1 = Node->getOperand(1);
2018  for (SDNode::use_iterator UI = Op0.getNode()->use_begin(),
2019         UE = Op0.getNode()->use_end(); UI != UE; ++UI) {
2020    SDNode *User = *UI;
2021    if (User == Node)
2022      continue;
2023    if ((User->getOpcode() == OtherOpcode || User->getOpcode() == DivRemOpc) &&
2024        User->getOperand(0) == Op0 &&
2025        User->getOperand(1) == Op1)
2026      return true;
2027  }
2028  return false;
2029}
2030
2031/// ExpandDivRemLibCall - Issue libcalls to __{u}divmod to compute div / rem
2032/// pairs.
2033void
2034SelectionDAGLegalize::ExpandDivRemLibCall(SDNode *Node,
2035                                          SmallVectorImpl<SDValue> &Results) {
2036  unsigned Opcode = Node->getOpcode();
2037  bool isSigned = Opcode == ISD::SDIVREM;
2038
2039  RTLIB::Libcall LC;
2040  switch (Node->getValueType(0).getSimpleVT().SimpleTy) {
2041  default: llvm_unreachable("Unexpected request for libcall!");
2042  case MVT::i8:   LC= isSigned ? RTLIB::SDIVREM_I8  : RTLIB::UDIVREM_I8;  break;
2043  case MVT::i16:  LC= isSigned ? RTLIB::SDIVREM_I16 : RTLIB::UDIVREM_I16; break;
2044  case MVT::i32:  LC= isSigned ? RTLIB::SDIVREM_I32 : RTLIB::UDIVREM_I32; break;
2045  case MVT::i64:  LC= isSigned ? RTLIB::SDIVREM_I64 : RTLIB::UDIVREM_I64; break;
2046  case MVT::i128: LC= isSigned ? RTLIB::SDIVREM_I128:RTLIB::UDIVREM_I128; break;
2047  }
2048
2049  // The input chain to this libcall is the entry node of the function.
2050  // Legalizing the call will automatically add the previous call to the
2051  // dependence.
2052  SDValue InChain = DAG.getEntryNode();
2053
2054  EVT RetVT = Node->getValueType(0);
2055  Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
2056
2057  TargetLowering::ArgListTy Args;
2058  TargetLowering::ArgListEntry Entry;
2059  for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
2060    EVT ArgVT = Node->getOperand(i).getValueType();
2061    Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
2062    Entry.Node = Node->getOperand(i); Entry.Ty = ArgTy;
2063    Entry.isSExt = isSigned;
2064    Entry.isZExt = !isSigned;
2065    Args.push_back(Entry);
2066  }
2067
2068  // Also pass the return address of the remainder.
2069  SDValue FIPtr = DAG.CreateStackTemporary(RetVT);
2070  Entry.Node = FIPtr;
2071  Entry.Ty = RetTy->getPointerTo();
2072  Entry.isSExt = isSigned;
2073  Entry.isZExt = !isSigned;
2074  Args.push_back(Entry);
2075
2076  SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
2077                                         TLI.getPointerTy());
2078
2079  DebugLoc dl = Node->getDebugLoc();
2080  TargetLowering::
2081  CallLoweringInfo CLI(InChain, RetTy, isSigned, !isSigned, false, false,
2082                    0, TLI.getLibcallCallingConv(LC), /*isTailCall=*/false,
2083                    /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
2084                    Callee, Args, DAG, dl);
2085  std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI);
2086
2087  // Remainder is loaded back from the stack frame.
2088  SDValue Rem = DAG.getLoad(RetVT, dl, CallInfo.second, FIPtr,
2089                            MachinePointerInfo(), false, false, false, 0);
2090  Results.push_back(CallInfo.first);
2091  Results.push_back(Rem);
2092}
2093
2094/// ExpandLegalINT_TO_FP - This function is responsible for legalizing a
2095/// INT_TO_FP operation of the specified operand when the target requests that
2096/// we expand it.  At this point, we know that the result and operand types are
2097/// legal for the target.
2098SDValue SelectionDAGLegalize::ExpandLegalINT_TO_FP(bool isSigned,
2099                                                   SDValue Op0,
2100                                                   EVT DestVT,
2101                                                   DebugLoc dl) {
2102  if (Op0.getValueType() == MVT::i32 && TLI.isTypeLegal(MVT::f64)) {
2103    // simple 32-bit [signed|unsigned] integer to float/double expansion
2104
2105    // Get the stack frame index of a 8 byte buffer.
2106    SDValue StackSlot = DAG.CreateStackTemporary(MVT::f64);
2107
2108    // word offset constant for Hi/Lo address computation
2109    SDValue WordOff = DAG.getConstant(sizeof(int), TLI.getPointerTy());
2110    // set up Hi and Lo (into buffer) address based on endian
2111    SDValue Hi = StackSlot;
2112    SDValue Lo = DAG.getNode(ISD::ADD, dl,
2113                             TLI.getPointerTy(), StackSlot, WordOff);
2114    if (TLI.isLittleEndian())
2115      std::swap(Hi, Lo);
2116
2117    // if signed map to unsigned space
2118    SDValue Op0Mapped;
2119    if (isSigned) {
2120      // constant used to invert sign bit (signed to unsigned mapping)
2121      SDValue SignBit = DAG.getConstant(0x80000000u, MVT::i32);
2122      Op0Mapped = DAG.getNode(ISD::XOR, dl, MVT::i32, Op0, SignBit);
2123    } else {
2124      Op0Mapped = Op0;
2125    }
2126    // store the lo of the constructed double - based on integer input
2127    SDValue Store1 = DAG.getStore(DAG.getEntryNode(), dl,
2128                                  Op0Mapped, Lo, MachinePointerInfo(),
2129                                  false, false, 0);
2130    // initial hi portion of constructed double
2131    SDValue InitialHi = DAG.getConstant(0x43300000u, MVT::i32);
2132    // store the hi of the constructed double - biased exponent
2133    SDValue Store2 = DAG.getStore(Store1, dl, InitialHi, Hi,
2134                                  MachinePointerInfo(),
2135                                  false, false, 0);
2136    // load the constructed double
2137    SDValue Load = DAG.getLoad(MVT::f64, dl, Store2, StackSlot,
2138                               MachinePointerInfo(), false, false, false, 0);
2139    // FP constant to bias correct the final result
2140    SDValue Bias = DAG.getConstantFP(isSigned ?
2141                                     BitsToDouble(0x4330000080000000ULL) :
2142                                     BitsToDouble(0x4330000000000000ULL),
2143                                     MVT::f64);
2144    // subtract the bias
2145    SDValue Sub = DAG.getNode(ISD::FSUB, dl, MVT::f64, Load, Bias);
2146    // final result
2147    SDValue Result;
2148    // handle final rounding
2149    if (DestVT == MVT::f64) {
2150      // do nothing
2151      Result = Sub;
2152    } else if (DestVT.bitsLT(MVT::f64)) {
2153      Result = DAG.getNode(ISD::FP_ROUND, dl, DestVT, Sub,
2154                           DAG.getIntPtrConstant(0));
2155    } else if (DestVT.bitsGT(MVT::f64)) {
2156      Result = DAG.getNode(ISD::FP_EXTEND, dl, DestVT, Sub);
2157    }
2158    return Result;
2159  }
2160  assert(!isSigned && "Legalize cannot Expand SINT_TO_FP for i64 yet");
2161  // Code below here assumes !isSigned without checking again.
2162
2163  // Implementation of unsigned i64 to f64 following the algorithm in
2164  // __floatundidf in compiler_rt. This implementation has the advantage
2165  // of performing rounding correctly, both in the default rounding mode
2166  // and in all alternate rounding modes.
2167  // TODO: Generalize this for use with other types.
2168  if (Op0.getValueType() == MVT::i64 && DestVT == MVT::f64) {
2169    SDValue TwoP52 =
2170      DAG.getConstant(UINT64_C(0x4330000000000000), MVT::i64);
2171    SDValue TwoP84PlusTwoP52 =
2172      DAG.getConstantFP(BitsToDouble(UINT64_C(0x4530000000100000)), MVT::f64);
2173    SDValue TwoP84 =
2174      DAG.getConstant(UINT64_C(0x4530000000000000), MVT::i64);
2175
2176    SDValue Lo = DAG.getZeroExtendInReg(Op0, dl, MVT::i32);
2177    SDValue Hi = DAG.getNode(ISD::SRL, dl, MVT::i64, Op0,
2178                             DAG.getConstant(32, MVT::i64));
2179    SDValue LoOr = DAG.getNode(ISD::OR, dl, MVT::i64, Lo, TwoP52);
2180    SDValue HiOr = DAG.getNode(ISD::OR, dl, MVT::i64, Hi, TwoP84);
2181    SDValue LoFlt = DAG.getNode(ISD::BITCAST, dl, MVT::f64, LoOr);
2182    SDValue HiFlt = DAG.getNode(ISD::BITCAST, dl, MVT::f64, HiOr);
2183    SDValue HiSub = DAG.getNode(ISD::FSUB, dl, MVT::f64, HiFlt,
2184                                TwoP84PlusTwoP52);
2185    return DAG.getNode(ISD::FADD, dl, MVT::f64, LoFlt, HiSub);
2186  }
2187
2188  // Implementation of unsigned i64 to f32.
2189  // TODO: Generalize this for use with other types.
2190  if (Op0.getValueType() == MVT::i64 && DestVT == MVT::f32) {
2191    // For unsigned conversions, convert them to signed conversions using the
2192    // algorithm from the x86_64 __floatundidf in compiler_rt.
2193    if (!isSigned) {
2194      SDValue Fast = DAG.getNode(ISD::SINT_TO_FP, dl, MVT::f32, Op0);
2195
2196      SDValue ShiftConst =
2197          DAG.getConstant(1, TLI.getShiftAmountTy(Op0.getValueType()));
2198      SDValue Shr = DAG.getNode(ISD::SRL, dl, MVT::i64, Op0, ShiftConst);
2199      SDValue AndConst = DAG.getConstant(1, MVT::i64);
2200      SDValue And = DAG.getNode(ISD::AND, dl, MVT::i64, Op0, AndConst);
2201      SDValue Or = DAG.getNode(ISD::OR, dl, MVT::i64, And, Shr);
2202
2203      SDValue SignCvt = DAG.getNode(ISD::SINT_TO_FP, dl, MVT::f32, Or);
2204      SDValue Slow = DAG.getNode(ISD::FADD, dl, MVT::f32, SignCvt, SignCvt);
2205
2206      // TODO: This really should be implemented using a branch rather than a
2207      // select.  We happen to get lucky and machinesink does the right
2208      // thing most of the time.  This would be a good candidate for a
2209      //pseudo-op, or, even better, for whole-function isel.
2210      SDValue SignBitTest = DAG.getSetCC(dl, TLI.getSetCCResultType(MVT::i64),
2211        Op0, DAG.getConstant(0, MVT::i64), ISD::SETLT);
2212      return DAG.getNode(ISD::SELECT, dl, MVT::f32, SignBitTest, Slow, Fast);
2213    }
2214
2215    // Otherwise, implement the fully general conversion.
2216
2217    SDValue And = DAG.getNode(ISD::AND, dl, MVT::i64, Op0,
2218         DAG.getConstant(UINT64_C(0xfffffffffffff800), MVT::i64));
2219    SDValue Or = DAG.getNode(ISD::OR, dl, MVT::i64, And,
2220         DAG.getConstant(UINT64_C(0x800), MVT::i64));
2221    SDValue And2 = DAG.getNode(ISD::AND, dl, MVT::i64, Op0,
2222         DAG.getConstant(UINT64_C(0x7ff), MVT::i64));
2223    SDValue Ne = DAG.getSetCC(dl, TLI.getSetCCResultType(MVT::i64),
2224                   And2, DAG.getConstant(UINT64_C(0), MVT::i64), ISD::SETNE);
2225    SDValue Sel = DAG.getNode(ISD::SELECT, dl, MVT::i64, Ne, Or, Op0);
2226    SDValue Ge = DAG.getSetCC(dl, TLI.getSetCCResultType(MVT::i64),
2227                   Op0, DAG.getConstant(UINT64_C(0x0020000000000000), MVT::i64),
2228                   ISD::SETUGE);
2229    SDValue Sel2 = DAG.getNode(ISD::SELECT, dl, MVT::i64, Ge, Sel, Op0);
2230    EVT SHVT = TLI.getShiftAmountTy(Sel2.getValueType());
2231
2232    SDValue Sh = DAG.getNode(ISD::SRL, dl, MVT::i64, Sel2,
2233                             DAG.getConstant(32, SHVT));
2234    SDValue Trunc = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, Sh);
2235    SDValue Fcvt = DAG.getNode(ISD::UINT_TO_FP, dl, MVT::f64, Trunc);
2236    SDValue TwoP32 =
2237      DAG.getConstantFP(BitsToDouble(UINT64_C(0x41f0000000000000)), MVT::f64);
2238    SDValue Fmul = DAG.getNode(ISD::FMUL, dl, MVT::f64, TwoP32, Fcvt);
2239    SDValue Lo = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, Sel2);
2240    SDValue Fcvt2 = DAG.getNode(ISD::UINT_TO_FP, dl, MVT::f64, Lo);
2241    SDValue Fadd = DAG.getNode(ISD::FADD, dl, MVT::f64, Fmul, Fcvt2);
2242    return DAG.getNode(ISD::FP_ROUND, dl, MVT::f32, Fadd,
2243                       DAG.getIntPtrConstant(0));
2244  }
2245
2246  SDValue Tmp1 = DAG.getNode(ISD::SINT_TO_FP, dl, DestVT, Op0);
2247
2248  SDValue SignSet = DAG.getSetCC(dl, TLI.getSetCCResultType(Op0.getValueType()),
2249                                 Op0, DAG.getConstant(0, Op0.getValueType()),
2250                                 ISD::SETLT);
2251  SDValue Zero = DAG.getIntPtrConstant(0), Four = DAG.getIntPtrConstant(4);
2252  SDValue CstOffset = DAG.getNode(ISD::SELECT, dl, Zero.getValueType(),
2253                                    SignSet, Four, Zero);
2254
2255  // If the sign bit of the integer is set, the large number will be treated
2256  // as a negative number.  To counteract this, the dynamic code adds an
2257  // offset depending on the data type.
2258  uint64_t FF;
2259  switch (Op0.getValueType().getSimpleVT().SimpleTy) {
2260  default: llvm_unreachable("Unsupported integer type!");
2261  case MVT::i8 : FF = 0x43800000ULL; break;  // 2^8  (as a float)
2262  case MVT::i16: FF = 0x47800000ULL; break;  // 2^16 (as a float)
2263  case MVT::i32: FF = 0x4F800000ULL; break;  // 2^32 (as a float)
2264  case MVT::i64: FF = 0x5F800000ULL; break;  // 2^64 (as a float)
2265  }
2266  if (TLI.isLittleEndian()) FF <<= 32;
2267  Constant *FudgeFactor = ConstantInt::get(
2268                                       Type::getInt64Ty(*DAG.getContext()), FF);
2269
2270  SDValue CPIdx = DAG.getConstantPool(FudgeFactor, TLI.getPointerTy());
2271  unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
2272  CPIdx = DAG.getNode(ISD::ADD, dl, TLI.getPointerTy(), CPIdx, CstOffset);
2273  Alignment = std::min(Alignment, 4u);
2274  SDValue FudgeInReg;
2275  if (DestVT == MVT::f32)
2276    FudgeInReg = DAG.getLoad(MVT::f32, dl, DAG.getEntryNode(), CPIdx,
2277                             MachinePointerInfo::getConstantPool(),
2278                             false, false, false, Alignment);
2279  else {
2280    SDValue Load = DAG.getExtLoad(ISD::EXTLOAD, dl, DestVT,
2281                                  DAG.getEntryNode(), CPIdx,
2282                                  MachinePointerInfo::getConstantPool(),
2283                                  MVT::f32, false, false, Alignment);
2284    HandleSDNode Handle(Load);
2285    LegalizeOp(Load.getNode());
2286    FudgeInReg = Handle.getValue();
2287  }
2288
2289  return DAG.getNode(ISD::FADD, dl, DestVT, Tmp1, FudgeInReg);
2290}
2291
2292/// PromoteLegalINT_TO_FP - This function is responsible for legalizing a
2293/// *INT_TO_FP operation of the specified operand when the target requests that
2294/// we promote it.  At this point, we know that the result and operand types are
2295/// legal for the target, and that there is a legal UINT_TO_FP or SINT_TO_FP
2296/// operation that takes a larger input.
2297SDValue SelectionDAGLegalize::PromoteLegalINT_TO_FP(SDValue LegalOp,
2298                                                    EVT DestVT,
2299                                                    bool isSigned,
2300                                                    DebugLoc dl) {
2301  // First step, figure out the appropriate *INT_TO_FP operation to use.
2302  EVT NewInTy = LegalOp.getValueType();
2303
2304  unsigned OpToUse = 0;
2305
2306  // Scan for the appropriate larger type to use.
2307  while (1) {
2308    NewInTy = (MVT::SimpleValueType)(NewInTy.getSimpleVT().SimpleTy+1);
2309    assert(NewInTy.isInteger() && "Ran out of possibilities!");
2310
2311    // If the target supports SINT_TO_FP of this type, use it.
2312    if (TLI.isOperationLegalOrCustom(ISD::SINT_TO_FP, NewInTy)) {
2313      OpToUse = ISD::SINT_TO_FP;
2314      break;
2315    }
2316    if (isSigned) continue;
2317
2318    // If the target supports UINT_TO_FP of this type, use it.
2319    if (TLI.isOperationLegalOrCustom(ISD::UINT_TO_FP, NewInTy)) {
2320      OpToUse = ISD::UINT_TO_FP;
2321      break;
2322    }
2323
2324    // Otherwise, try a larger type.
2325  }
2326
2327  // Okay, we found the operation and type to use.  Zero extend our input to the
2328  // desired type then run the operation on it.
2329  return DAG.getNode(OpToUse, dl, DestVT,
2330                     DAG.getNode(isSigned ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND,
2331                                 dl, NewInTy, LegalOp));
2332}
2333
2334/// PromoteLegalFP_TO_INT - This function is responsible for legalizing a
2335/// FP_TO_*INT operation of the specified operand when the target requests that
2336/// we promote it.  At this point, we know that the result and operand types are
2337/// legal for the target, and that there is a legal FP_TO_UINT or FP_TO_SINT
2338/// operation that returns a larger result.
2339SDValue SelectionDAGLegalize::PromoteLegalFP_TO_INT(SDValue LegalOp,
2340                                                    EVT DestVT,
2341                                                    bool isSigned,
2342                                                    DebugLoc dl) {
2343  // First step, figure out the appropriate FP_TO*INT operation to use.
2344  EVT NewOutTy = DestVT;
2345
2346  unsigned OpToUse = 0;
2347
2348  // Scan for the appropriate larger type to use.
2349  while (1) {
2350    NewOutTy = (MVT::SimpleValueType)(NewOutTy.getSimpleVT().SimpleTy+1);
2351    assert(NewOutTy.isInteger() && "Ran out of possibilities!");
2352
2353    if (TLI.isOperationLegalOrCustom(ISD::FP_TO_SINT, NewOutTy)) {
2354      OpToUse = ISD::FP_TO_SINT;
2355      break;
2356    }
2357
2358    if (TLI.isOperationLegalOrCustom(ISD::FP_TO_UINT, NewOutTy)) {
2359      OpToUse = ISD::FP_TO_UINT;
2360      break;
2361    }
2362
2363    // Otherwise, try a larger type.
2364  }
2365
2366
2367  // Okay, we found the operation and type to use.
2368  SDValue Operation = DAG.getNode(OpToUse, dl, NewOutTy, LegalOp);
2369
2370  // Truncate the result of the extended FP_TO_*INT operation to the desired
2371  // size.
2372  return DAG.getNode(ISD::TRUNCATE, dl, DestVT, Operation);
2373}
2374
2375/// ExpandBSWAP - Open code the operations for BSWAP of the specified operation.
2376///
2377SDValue SelectionDAGLegalize::ExpandBSWAP(SDValue Op, DebugLoc dl) {
2378  EVT VT = Op.getValueType();
2379  EVT SHVT = TLI.getShiftAmountTy(VT);
2380  SDValue Tmp1, Tmp2, Tmp3, Tmp4, Tmp5, Tmp6, Tmp7, Tmp8;
2381  switch (VT.getSimpleVT().SimpleTy) {
2382  default: llvm_unreachable("Unhandled Expand type in BSWAP!");
2383  case MVT::i16:
2384    Tmp2 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, SHVT));
2385    Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, SHVT));
2386    return DAG.getNode(ISD::OR, dl, VT, Tmp1, Tmp2);
2387  case MVT::i32:
2388    Tmp4 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(24, SHVT));
2389    Tmp3 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, SHVT));
2390    Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, SHVT));
2391    Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(24, SHVT));
2392    Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp3, DAG.getConstant(0xFF0000, VT));
2393    Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2, DAG.getConstant(0xFF00, VT));
2394    Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp3);
2395    Tmp2 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp1);
2396    return DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp2);
2397  case MVT::i64:
2398    Tmp8 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(56, SHVT));
2399    Tmp7 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(40, SHVT));
2400    Tmp6 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(24, SHVT));
2401    Tmp5 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, SHVT));
2402    Tmp4 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, SHVT));
2403    Tmp3 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(24, SHVT));
2404    Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(40, SHVT));
2405    Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(56, SHVT));
2406    Tmp7 = DAG.getNode(ISD::AND, dl, VT, Tmp7, DAG.getConstant(255ULL<<48, VT));
2407    Tmp6 = DAG.getNode(ISD::AND, dl, VT, Tmp6, DAG.getConstant(255ULL<<40, VT));
2408    Tmp5 = DAG.getNode(ISD::AND, dl, VT, Tmp5, DAG.getConstant(255ULL<<32, VT));
2409    Tmp4 = DAG.getNode(ISD::AND, dl, VT, Tmp4, DAG.getConstant(255ULL<<24, VT));
2410    Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp3, DAG.getConstant(255ULL<<16, VT));
2411    Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2, DAG.getConstant(255ULL<<8 , VT));
2412    Tmp8 = DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp7);
2413    Tmp6 = DAG.getNode(ISD::OR, dl, VT, Tmp6, Tmp5);
2414    Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp3);
2415    Tmp2 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp1);
2416    Tmp8 = DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp6);
2417    Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp2);
2418    return DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp4);
2419  }
2420}
2421
2422/// SplatByte - Distribute ByteVal over NumBits bits.
2423// FIXME: Move this helper to a common place.
2424static APInt SplatByte(unsigned NumBits, uint8_t ByteVal) {
2425  APInt Val = APInt(NumBits, ByteVal);
2426  unsigned Shift = 8;
2427  for (unsigned i = NumBits; i > 8; i >>= 1) {
2428    Val = (Val << Shift) | Val;
2429    Shift <<= 1;
2430  }
2431  return Val;
2432}
2433
2434/// ExpandBitCount - Expand the specified bitcount instruction into operations.
2435///
2436SDValue SelectionDAGLegalize::ExpandBitCount(unsigned Opc, SDValue Op,
2437                                             DebugLoc dl) {
2438  switch (Opc) {
2439  default: llvm_unreachable("Cannot expand this yet!");
2440  case ISD::CTPOP: {
2441    EVT VT = Op.getValueType();
2442    EVT ShVT = TLI.getShiftAmountTy(VT);
2443    unsigned Len = VT.getSizeInBits();
2444
2445    assert(VT.isInteger() && Len <= 128 && Len % 8 == 0 &&
2446           "CTPOP not implemented for this type.");
2447
2448    // This is the "best" algorithm from
2449    // http://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetParallel
2450
2451    SDValue Mask55 = DAG.getConstant(SplatByte(Len, 0x55), VT);
2452    SDValue Mask33 = DAG.getConstant(SplatByte(Len, 0x33), VT);
2453    SDValue Mask0F = DAG.getConstant(SplatByte(Len, 0x0F), VT);
2454    SDValue Mask01 = DAG.getConstant(SplatByte(Len, 0x01), VT);
2455
2456    // v = v - ((v >> 1) & 0x55555555...)
2457    Op = DAG.getNode(ISD::SUB, dl, VT, Op,
2458                     DAG.getNode(ISD::AND, dl, VT,
2459                                 DAG.getNode(ISD::SRL, dl, VT, Op,
2460                                             DAG.getConstant(1, ShVT)),
2461                                 Mask55));
2462    // v = (v & 0x33333333...) + ((v >> 2) & 0x33333333...)
2463    Op = DAG.getNode(ISD::ADD, dl, VT,
2464                     DAG.getNode(ISD::AND, dl, VT, Op, Mask33),
2465                     DAG.getNode(ISD::AND, dl, VT,
2466                                 DAG.getNode(ISD::SRL, dl, VT, Op,
2467                                             DAG.getConstant(2, ShVT)),
2468                                 Mask33));
2469    // v = (v + (v >> 4)) & 0x0F0F0F0F...
2470    Op = DAG.getNode(ISD::AND, dl, VT,
2471                     DAG.getNode(ISD::ADD, dl, VT, Op,
2472                                 DAG.getNode(ISD::SRL, dl, VT, Op,
2473                                             DAG.getConstant(4, ShVT))),
2474                     Mask0F);
2475    // v = (v * 0x01010101...) >> (Len - 8)
2476    Op = DAG.getNode(ISD::SRL, dl, VT,
2477                     DAG.getNode(ISD::MUL, dl, VT, Op, Mask01),
2478                     DAG.getConstant(Len - 8, ShVT));
2479
2480    return Op;
2481  }
2482  case ISD::CTLZ_ZERO_UNDEF:
2483    // This trivially expands to CTLZ.
2484    return DAG.getNode(ISD::CTLZ, dl, Op.getValueType(), Op);
2485  case ISD::CTLZ: {
2486    // for now, we do this:
2487    // x = x | (x >> 1);
2488    // x = x | (x >> 2);
2489    // ...
2490    // x = x | (x >>16);
2491    // x = x | (x >>32); // for 64-bit input
2492    // return popcount(~x);
2493    //
2494    // but see also: http://www.hackersdelight.org/HDcode/nlz.cc
2495    EVT VT = Op.getValueType();
2496    EVT ShVT = TLI.getShiftAmountTy(VT);
2497    unsigned len = VT.getSizeInBits();
2498    for (unsigned i = 0; (1U << i) <= (len / 2); ++i) {
2499      SDValue Tmp3 = DAG.getConstant(1ULL << i, ShVT);
2500      Op = DAG.getNode(ISD::OR, dl, VT, Op,
2501                       DAG.getNode(ISD::SRL, dl, VT, Op, Tmp3));
2502    }
2503    Op = DAG.getNOT(dl, Op, VT);
2504    return DAG.getNode(ISD::CTPOP, dl, VT, Op);
2505  }
2506  case ISD::CTTZ_ZERO_UNDEF:
2507    // This trivially expands to CTTZ.
2508    return DAG.getNode(ISD::CTTZ, dl, Op.getValueType(), Op);
2509  case ISD::CTTZ: {
2510    // for now, we use: { return popcount(~x & (x - 1)); }
2511    // unless the target has ctlz but not ctpop, in which case we use:
2512    // { return 32 - nlz(~x & (x-1)); }
2513    // see also http://www.hackersdelight.org/HDcode/ntz.cc
2514    EVT VT = Op.getValueType();
2515    SDValue Tmp3 = DAG.getNode(ISD::AND, dl, VT,
2516                               DAG.getNOT(dl, Op, VT),
2517                               DAG.getNode(ISD::SUB, dl, VT, Op,
2518                                           DAG.getConstant(1, VT)));
2519    // If ISD::CTLZ is legal and CTPOP isn't, then do that instead.
2520    if (!TLI.isOperationLegalOrCustom(ISD::CTPOP, VT) &&
2521        TLI.isOperationLegalOrCustom(ISD::CTLZ, VT))
2522      return DAG.getNode(ISD::SUB, dl, VT,
2523                         DAG.getConstant(VT.getSizeInBits(), VT),
2524                         DAG.getNode(ISD::CTLZ, dl, VT, Tmp3));
2525    return DAG.getNode(ISD::CTPOP, dl, VT, Tmp3);
2526  }
2527  }
2528}
2529
2530std::pair <SDValue, SDValue> SelectionDAGLegalize::ExpandAtomic(SDNode *Node) {
2531  unsigned Opc = Node->getOpcode();
2532  MVT VT = cast<AtomicSDNode>(Node)->getMemoryVT().getSimpleVT();
2533  RTLIB::Libcall LC;
2534
2535  switch (Opc) {
2536  default:
2537    llvm_unreachable("Unhandled atomic intrinsic Expand!");
2538  case ISD::ATOMIC_SWAP:
2539    switch (VT.SimpleTy) {
2540    default: llvm_unreachable("Unexpected value type for atomic!");
2541    case MVT::i8:  LC = RTLIB::SYNC_LOCK_TEST_AND_SET_1; break;
2542    case MVT::i16: LC = RTLIB::SYNC_LOCK_TEST_AND_SET_2; break;
2543    case MVT::i32: LC = RTLIB::SYNC_LOCK_TEST_AND_SET_4; break;
2544    case MVT::i64: LC = RTLIB::SYNC_LOCK_TEST_AND_SET_8; break;
2545    }
2546    break;
2547  case ISD::ATOMIC_CMP_SWAP:
2548    switch (VT.SimpleTy) {
2549    default: llvm_unreachable("Unexpected value type for atomic!");
2550    case MVT::i8:  LC = RTLIB::SYNC_VAL_COMPARE_AND_SWAP_1; break;
2551    case MVT::i16: LC = RTLIB::SYNC_VAL_COMPARE_AND_SWAP_2; break;
2552    case MVT::i32: LC = RTLIB::SYNC_VAL_COMPARE_AND_SWAP_4; break;
2553    case MVT::i64: LC = RTLIB::SYNC_VAL_COMPARE_AND_SWAP_8; break;
2554    }
2555    break;
2556  case ISD::ATOMIC_LOAD_ADD:
2557    switch (VT.SimpleTy) {
2558    default: llvm_unreachable("Unexpected value type for atomic!");
2559    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_ADD_1; break;
2560    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_ADD_2; break;
2561    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_ADD_4; break;
2562    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_ADD_8; break;
2563    }
2564    break;
2565  case ISD::ATOMIC_LOAD_SUB:
2566    switch (VT.SimpleTy) {
2567    default: llvm_unreachable("Unexpected value type for atomic!");
2568    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_SUB_1; break;
2569    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_SUB_2; break;
2570    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_SUB_4; break;
2571    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_SUB_8; break;
2572    }
2573    break;
2574  case ISD::ATOMIC_LOAD_AND:
2575    switch (VT.SimpleTy) {
2576    default: llvm_unreachable("Unexpected value type for atomic!");
2577    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_AND_1; break;
2578    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_AND_2; break;
2579    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_AND_4; break;
2580    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_AND_8; break;
2581    }
2582    break;
2583  case ISD::ATOMIC_LOAD_OR:
2584    switch (VT.SimpleTy) {
2585    default: llvm_unreachable("Unexpected value type for atomic!");
2586    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_OR_1; break;
2587    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_OR_2; break;
2588    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_OR_4; break;
2589    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_OR_8; break;
2590    }
2591    break;
2592  case ISD::ATOMIC_LOAD_XOR:
2593    switch (VT.SimpleTy) {
2594    default: llvm_unreachable("Unexpected value type for atomic!");
2595    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_XOR_1; break;
2596    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_XOR_2; break;
2597    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_XOR_4; break;
2598    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_XOR_8; break;
2599    }
2600    break;
2601  case ISD::ATOMIC_LOAD_NAND:
2602    switch (VT.SimpleTy) {
2603    default: llvm_unreachable("Unexpected value type for atomic!");
2604    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_NAND_1; break;
2605    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_NAND_2; break;
2606    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_NAND_4; break;
2607    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_NAND_8; break;
2608    }
2609    break;
2610  }
2611
2612  return ExpandChainLibCall(LC, Node, false);
2613}
2614
2615void SelectionDAGLegalize::ExpandNode(SDNode *Node) {
2616  SmallVector<SDValue, 8> Results;
2617  DebugLoc dl = Node->getDebugLoc();
2618  SDValue Tmp1, Tmp2, Tmp3, Tmp4;
2619  switch (Node->getOpcode()) {
2620  case ISD::CTPOP:
2621  case ISD::CTLZ:
2622  case ISD::CTLZ_ZERO_UNDEF:
2623  case ISD::CTTZ:
2624  case ISD::CTTZ_ZERO_UNDEF:
2625    Tmp1 = ExpandBitCount(Node->getOpcode(), Node->getOperand(0), dl);
2626    Results.push_back(Tmp1);
2627    break;
2628  case ISD::BSWAP:
2629    Results.push_back(ExpandBSWAP(Node->getOperand(0), dl));
2630    break;
2631  case ISD::FRAMEADDR:
2632  case ISD::RETURNADDR:
2633  case ISD::FRAME_TO_ARGS_OFFSET:
2634    Results.push_back(DAG.getConstant(0, Node->getValueType(0)));
2635    break;
2636  case ISD::FLT_ROUNDS_:
2637    Results.push_back(DAG.getConstant(1, Node->getValueType(0)));
2638    break;
2639  case ISD::EH_RETURN:
2640  case ISD::EH_LABEL:
2641  case ISD::PREFETCH:
2642  case ISD::VAEND:
2643  case ISD::EH_SJLJ_LONGJMP:
2644    // If the target didn't expand these, there's nothing to do, so just
2645    // preserve the chain and be done.
2646    Results.push_back(Node->getOperand(0));
2647    break;
2648  case ISD::EH_SJLJ_SETJMP:
2649    // If the target didn't expand this, just return 'zero' and preserve the
2650    // chain.
2651    Results.push_back(DAG.getConstant(0, MVT::i32));
2652    Results.push_back(Node->getOperand(0));
2653    break;
2654  case ISD::ATOMIC_FENCE:
2655  case ISD::MEMBARRIER: {
2656    // If the target didn't lower this, lower it to '__sync_synchronize()' call
2657    // FIXME: handle "fence singlethread" more efficiently.
2658    TargetLowering::ArgListTy Args;
2659    TargetLowering::
2660    CallLoweringInfo CLI(Node->getOperand(0),
2661                         Type::getVoidTy(*DAG.getContext()),
2662                      false, false, false, false, 0, CallingConv::C,
2663                      /*isTailCall=*/false,
2664                      /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
2665                      DAG.getExternalSymbol("__sync_synchronize",
2666                                            TLI.getPointerTy()),
2667                      Args, DAG, dl);
2668    std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
2669
2670    Results.push_back(CallResult.second);
2671    break;
2672  }
2673  case ISD::ATOMIC_LOAD: {
2674    // There is no libcall for atomic load; fake it with ATOMIC_CMP_SWAP.
2675    SDValue Zero = DAG.getConstant(0, Node->getValueType(0));
2676    SDValue Swap = DAG.getAtomic(ISD::ATOMIC_CMP_SWAP, dl,
2677                                 cast<AtomicSDNode>(Node)->getMemoryVT(),
2678                                 Node->getOperand(0),
2679                                 Node->getOperand(1), Zero, Zero,
2680                                 cast<AtomicSDNode>(Node)->getMemOperand(),
2681                                 cast<AtomicSDNode>(Node)->getOrdering(),
2682                                 cast<AtomicSDNode>(Node)->getSynchScope());
2683    Results.push_back(Swap.getValue(0));
2684    Results.push_back(Swap.getValue(1));
2685    break;
2686  }
2687  case ISD::ATOMIC_STORE: {
2688    // There is no libcall for atomic store; fake it with ATOMIC_SWAP.
2689    SDValue Swap = DAG.getAtomic(ISD::ATOMIC_SWAP, dl,
2690                                 cast<AtomicSDNode>(Node)->getMemoryVT(),
2691                                 Node->getOperand(0),
2692                                 Node->getOperand(1), Node->getOperand(2),
2693                                 cast<AtomicSDNode>(Node)->getMemOperand(),
2694                                 cast<AtomicSDNode>(Node)->getOrdering(),
2695                                 cast<AtomicSDNode>(Node)->getSynchScope());
2696    Results.push_back(Swap.getValue(1));
2697    break;
2698  }
2699  // By default, atomic intrinsics are marked Legal and lowered. Targets
2700  // which don't support them directly, however, may want libcalls, in which
2701  // case they mark them Expand, and we get here.
2702  case ISD::ATOMIC_SWAP:
2703  case ISD::ATOMIC_LOAD_ADD:
2704  case ISD::ATOMIC_LOAD_SUB:
2705  case ISD::ATOMIC_LOAD_AND:
2706  case ISD::ATOMIC_LOAD_OR:
2707  case ISD::ATOMIC_LOAD_XOR:
2708  case ISD::ATOMIC_LOAD_NAND:
2709  case ISD::ATOMIC_LOAD_MIN:
2710  case ISD::ATOMIC_LOAD_MAX:
2711  case ISD::ATOMIC_LOAD_UMIN:
2712  case ISD::ATOMIC_LOAD_UMAX:
2713  case ISD::ATOMIC_CMP_SWAP: {
2714    std::pair<SDValue, SDValue> Tmp = ExpandAtomic(Node);
2715    Results.push_back(Tmp.first);
2716    Results.push_back(Tmp.second);
2717    break;
2718  }
2719  case ISD::DYNAMIC_STACKALLOC:
2720    ExpandDYNAMIC_STACKALLOC(Node, Results);
2721    break;
2722  case ISD::MERGE_VALUES:
2723    for (unsigned i = 0; i < Node->getNumValues(); i++)
2724      Results.push_back(Node->getOperand(i));
2725    break;
2726  case ISD::UNDEF: {
2727    EVT VT = Node->getValueType(0);
2728    if (VT.isInteger())
2729      Results.push_back(DAG.getConstant(0, VT));
2730    else {
2731      assert(VT.isFloatingPoint() && "Unknown value type!");
2732      Results.push_back(DAG.getConstantFP(0, VT));
2733    }
2734    break;
2735  }
2736  case ISD::TRAP: {
2737    // If this operation is not supported, lower it to 'abort()' call
2738    TargetLowering::ArgListTy Args;
2739    TargetLowering::
2740    CallLoweringInfo CLI(Node->getOperand(0),
2741                         Type::getVoidTy(*DAG.getContext()),
2742                      false, false, false, false, 0, CallingConv::C,
2743                      /*isTailCall=*/false,
2744                      /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
2745                      DAG.getExternalSymbol("abort", TLI.getPointerTy()),
2746                      Args, DAG, dl);
2747    std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
2748
2749    Results.push_back(CallResult.second);
2750    break;
2751  }
2752  case ISD::FP_ROUND:
2753  case ISD::BITCAST:
2754    Tmp1 = EmitStackConvert(Node->getOperand(0), Node->getValueType(0),
2755                            Node->getValueType(0), dl);
2756    Results.push_back(Tmp1);
2757    break;
2758  case ISD::FP_EXTEND:
2759    Tmp1 = EmitStackConvert(Node->getOperand(0),
2760                            Node->getOperand(0).getValueType(),
2761                            Node->getValueType(0), dl);
2762    Results.push_back(Tmp1);
2763    break;
2764  case ISD::SIGN_EXTEND_INREG: {
2765    // NOTE: we could fall back on load/store here too for targets without
2766    // SAR.  However, it is doubtful that any exist.
2767    EVT ExtraVT = cast<VTSDNode>(Node->getOperand(1))->getVT();
2768    EVT VT = Node->getValueType(0);
2769    EVT ShiftAmountTy = TLI.getShiftAmountTy(VT);
2770    if (VT.isVector())
2771      ShiftAmountTy = VT;
2772    unsigned BitsDiff = VT.getScalarType().getSizeInBits() -
2773                        ExtraVT.getScalarType().getSizeInBits();
2774    SDValue ShiftCst = DAG.getConstant(BitsDiff, ShiftAmountTy);
2775    Tmp1 = DAG.getNode(ISD::SHL, dl, Node->getValueType(0),
2776                       Node->getOperand(0), ShiftCst);
2777    Tmp1 = DAG.getNode(ISD::SRA, dl, Node->getValueType(0), Tmp1, ShiftCst);
2778    Results.push_back(Tmp1);
2779    break;
2780  }
2781  case ISD::FP_ROUND_INREG: {
2782    // The only way we can lower this is to turn it into a TRUNCSTORE,
2783    // EXTLOAD pair, targeting a temporary location (a stack slot).
2784
2785    // NOTE: there is a choice here between constantly creating new stack
2786    // slots and always reusing the same one.  We currently always create
2787    // new ones, as reuse may inhibit scheduling.
2788    EVT ExtraVT = cast<VTSDNode>(Node->getOperand(1))->getVT();
2789    Tmp1 = EmitStackConvert(Node->getOperand(0), ExtraVT,
2790                            Node->getValueType(0), dl);
2791    Results.push_back(Tmp1);
2792    break;
2793  }
2794  case ISD::SINT_TO_FP:
2795  case ISD::UINT_TO_FP:
2796    Tmp1 = ExpandLegalINT_TO_FP(Node->getOpcode() == ISD::SINT_TO_FP,
2797                                Node->getOperand(0), Node->getValueType(0), dl);
2798    Results.push_back(Tmp1);
2799    break;
2800  case ISD::FP_TO_UINT: {
2801    SDValue True, False;
2802    EVT VT =  Node->getOperand(0).getValueType();
2803    EVT NVT = Node->getValueType(0);
2804    APFloat apf(APInt::getNullValue(VT.getSizeInBits()));
2805    APInt x = APInt::getSignBit(NVT.getSizeInBits());
2806    (void)apf.convertFromAPInt(x, false, APFloat::rmNearestTiesToEven);
2807    Tmp1 = DAG.getConstantFP(apf, VT);
2808    Tmp2 = DAG.getSetCC(dl, TLI.getSetCCResultType(VT),
2809                        Node->getOperand(0),
2810                        Tmp1, ISD::SETLT);
2811    True = DAG.getNode(ISD::FP_TO_SINT, dl, NVT, Node->getOperand(0));
2812    False = DAG.getNode(ISD::FP_TO_SINT, dl, NVT,
2813                        DAG.getNode(ISD::FSUB, dl, VT,
2814                                    Node->getOperand(0), Tmp1));
2815    False = DAG.getNode(ISD::XOR, dl, NVT, False,
2816                        DAG.getConstant(x, NVT));
2817    Tmp1 = DAG.getNode(ISD::SELECT, dl, NVT, Tmp2, True, False);
2818    Results.push_back(Tmp1);
2819    break;
2820  }
2821  case ISD::VAARG: {
2822    const Value *V = cast<SrcValueSDNode>(Node->getOperand(2))->getValue();
2823    EVT VT = Node->getValueType(0);
2824    Tmp1 = Node->getOperand(0);
2825    Tmp2 = Node->getOperand(1);
2826    unsigned Align = Node->getConstantOperandVal(3);
2827
2828    SDValue VAListLoad = DAG.getLoad(TLI.getPointerTy(), dl, Tmp1, Tmp2,
2829                                     MachinePointerInfo(V),
2830                                     false, false, false, 0);
2831    SDValue VAList = VAListLoad;
2832
2833    if (Align > TLI.getMinStackArgumentAlignment()) {
2834      assert(((Align & (Align-1)) == 0) && "Expected Align to be a power of 2");
2835
2836      VAList = DAG.getNode(ISD::ADD, dl, TLI.getPointerTy(), VAList,
2837                           DAG.getConstant(Align - 1,
2838                                           TLI.getPointerTy()));
2839
2840      VAList = DAG.getNode(ISD::AND, dl, TLI.getPointerTy(), VAList,
2841                           DAG.getConstant(-(int64_t)Align,
2842                                           TLI.getPointerTy()));
2843    }
2844
2845    // Increment the pointer, VAList, to the next vaarg
2846    Tmp3 = DAG.getNode(ISD::ADD, dl, TLI.getPointerTy(), VAList,
2847                       DAG.getConstant(TLI.getDataLayout()->
2848                          getTypeAllocSize(VT.getTypeForEVT(*DAG.getContext())),
2849                                       TLI.getPointerTy()));
2850    // Store the incremented VAList to the legalized pointer
2851    Tmp3 = DAG.getStore(VAListLoad.getValue(1), dl, Tmp3, Tmp2,
2852                        MachinePointerInfo(V), false, false, 0);
2853    // Load the actual argument out of the pointer VAList
2854    Results.push_back(DAG.getLoad(VT, dl, Tmp3, VAList, MachinePointerInfo(),
2855                                  false, false, false, 0));
2856    Results.push_back(Results[0].getValue(1));
2857    break;
2858  }
2859  case ISD::VACOPY: {
2860    // This defaults to loading a pointer from the input and storing it to the
2861    // output, returning the chain.
2862    const Value *VD = cast<SrcValueSDNode>(Node->getOperand(3))->getValue();
2863    const Value *VS = cast<SrcValueSDNode>(Node->getOperand(4))->getValue();
2864    Tmp1 = DAG.getLoad(TLI.getPointerTy(), dl, Node->getOperand(0),
2865                       Node->getOperand(2), MachinePointerInfo(VS),
2866                       false, false, false, 0);
2867    Tmp1 = DAG.getStore(Tmp1.getValue(1), dl, Tmp1, Node->getOperand(1),
2868                        MachinePointerInfo(VD), false, false, 0);
2869    Results.push_back(Tmp1);
2870    break;
2871  }
2872  case ISD::EXTRACT_VECTOR_ELT:
2873    if (Node->getOperand(0).getValueType().getVectorNumElements() == 1)
2874      // This must be an access of the only element.  Return it.
2875      Tmp1 = DAG.getNode(ISD::BITCAST, dl, Node->getValueType(0),
2876                         Node->getOperand(0));
2877    else
2878      Tmp1 = ExpandExtractFromVectorThroughStack(SDValue(Node, 0));
2879    Results.push_back(Tmp1);
2880    break;
2881  case ISD::EXTRACT_SUBVECTOR:
2882    Results.push_back(ExpandExtractFromVectorThroughStack(SDValue(Node, 0)));
2883    break;
2884  case ISD::INSERT_SUBVECTOR:
2885    Results.push_back(ExpandInsertToVectorThroughStack(SDValue(Node, 0)));
2886    break;
2887  case ISD::CONCAT_VECTORS: {
2888    Results.push_back(ExpandVectorBuildThroughStack(Node));
2889    break;
2890  }
2891  case ISD::SCALAR_TO_VECTOR:
2892    Results.push_back(ExpandSCALAR_TO_VECTOR(Node));
2893    break;
2894  case ISD::INSERT_VECTOR_ELT:
2895    Results.push_back(ExpandINSERT_VECTOR_ELT(Node->getOperand(0),
2896                                              Node->getOperand(1),
2897                                              Node->getOperand(2), dl));
2898    break;
2899  case ISD::VECTOR_SHUFFLE: {
2900    SmallVector<int, 32> NewMask;
2901    ArrayRef<int> Mask = cast<ShuffleVectorSDNode>(Node)->getMask();
2902
2903    EVT VT = Node->getValueType(0);
2904    EVT EltVT = VT.getVectorElementType();
2905    SDValue Op0 = Node->getOperand(0);
2906    SDValue Op1 = Node->getOperand(1);
2907    if (!TLI.isTypeLegal(EltVT)) {
2908
2909      EVT NewEltVT = TLI.getTypeToTransformTo(*DAG.getContext(), EltVT);
2910
2911      // BUILD_VECTOR operands are allowed to be wider than the element type.
2912      // But if NewEltVT is smaller that EltVT the BUILD_VECTOR does not accept it
2913      if (NewEltVT.bitsLT(EltVT)) {
2914
2915        // Convert shuffle node.
2916        // If original node was v4i64 and the new EltVT is i32,
2917        // cast operands to v8i32 and re-build the mask.
2918
2919        // Calculate new VT, the size of the new VT should be equal to original.
2920        EVT NewVT = EVT::getVectorVT(*DAG.getContext(), NewEltVT,
2921                                      VT.getSizeInBits()/NewEltVT.getSizeInBits());
2922        assert(NewVT.bitsEq(VT));
2923
2924        // cast operands to new VT
2925        Op0 = DAG.getNode(ISD::BITCAST, dl, NewVT, Op0);
2926        Op1 = DAG.getNode(ISD::BITCAST, dl, NewVT, Op1);
2927
2928        // Convert the shuffle mask
2929        unsigned int factor = NewVT.getVectorNumElements()/VT.getVectorNumElements();
2930
2931        // EltVT gets smaller
2932        assert(factor > 0);
2933
2934        for (unsigned i = 0; i < VT.getVectorNumElements(); ++i) {
2935          if (Mask[i] < 0) {
2936            for (unsigned fi = 0; fi < factor; ++fi)
2937              NewMask.push_back(Mask[i]);
2938          }
2939          else {
2940            for (unsigned fi = 0; fi < factor; ++fi)
2941              NewMask.push_back(Mask[i]*factor+fi);
2942          }
2943        }
2944        Mask = NewMask;
2945        VT = NewVT;
2946      }
2947      EltVT = NewEltVT;
2948    }
2949    unsigned NumElems = VT.getVectorNumElements();
2950    SmallVector<SDValue, 16> Ops;
2951    for (unsigned i = 0; i != NumElems; ++i) {
2952      if (Mask[i] < 0) {
2953        Ops.push_back(DAG.getUNDEF(EltVT));
2954        continue;
2955      }
2956      unsigned Idx = Mask[i];
2957      if (Idx < NumElems)
2958        Ops.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, EltVT,
2959                                  Op0,
2960                                  DAG.getIntPtrConstant(Idx)));
2961      else
2962        Ops.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, EltVT,
2963                                  Op1,
2964                                  DAG.getIntPtrConstant(Idx - NumElems)));
2965    }
2966
2967    Tmp1 = DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], Ops.size());
2968    // We may have changed the BUILD_VECTOR type. Cast it back to the Node type.
2969    Tmp1 = DAG.getNode(ISD::BITCAST, dl, Node->getValueType(0), Tmp1);
2970    Results.push_back(Tmp1);
2971    break;
2972  }
2973  case ISD::EXTRACT_ELEMENT: {
2974    EVT OpTy = Node->getOperand(0).getValueType();
2975    if (cast<ConstantSDNode>(Node->getOperand(1))->getZExtValue()) {
2976      // 1 -> Hi
2977      Tmp1 = DAG.getNode(ISD::SRL, dl, OpTy, Node->getOperand(0),
2978                         DAG.getConstant(OpTy.getSizeInBits()/2,
2979                    TLI.getShiftAmountTy(Node->getOperand(0).getValueType())));
2980      Tmp1 = DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0), Tmp1);
2981    } else {
2982      // 0 -> Lo
2983      Tmp1 = DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0),
2984                         Node->getOperand(0));
2985    }
2986    Results.push_back(Tmp1);
2987    break;
2988  }
2989  case ISD::STACKSAVE:
2990    // Expand to CopyFromReg if the target set
2991    // StackPointerRegisterToSaveRestore.
2992    if (unsigned SP = TLI.getStackPointerRegisterToSaveRestore()) {
2993      Results.push_back(DAG.getCopyFromReg(Node->getOperand(0), dl, SP,
2994                                           Node->getValueType(0)));
2995      Results.push_back(Results[0].getValue(1));
2996    } else {
2997      Results.push_back(DAG.getUNDEF(Node->getValueType(0)));
2998      Results.push_back(Node->getOperand(0));
2999    }
3000    break;
3001  case ISD::STACKRESTORE:
3002    // Expand to CopyToReg if the target set
3003    // StackPointerRegisterToSaveRestore.
3004    if (unsigned SP = TLI.getStackPointerRegisterToSaveRestore()) {
3005      Results.push_back(DAG.getCopyToReg(Node->getOperand(0), dl, SP,
3006                                         Node->getOperand(1)));
3007    } else {
3008      Results.push_back(Node->getOperand(0));
3009    }
3010    break;
3011  case ISD::FCOPYSIGN:
3012    Results.push_back(ExpandFCOPYSIGN(Node));
3013    break;
3014  case ISD::FNEG:
3015    // Expand Y = FNEG(X) ->  Y = SUB -0.0, X
3016    Tmp1 = DAG.getConstantFP(-0.0, Node->getValueType(0));
3017    Tmp1 = DAG.getNode(ISD::FSUB, dl, Node->getValueType(0), Tmp1,
3018                       Node->getOperand(0));
3019    Results.push_back(Tmp1);
3020    break;
3021  case ISD::FABS: {
3022    // Expand Y = FABS(X) -> Y = (X >u 0.0) ? X : fneg(X).
3023    EVT VT = Node->getValueType(0);
3024    Tmp1 = Node->getOperand(0);
3025    Tmp2 = DAG.getConstantFP(0.0, VT);
3026    Tmp2 = DAG.getSetCC(dl, TLI.getSetCCResultType(Tmp1.getValueType()),
3027                        Tmp1, Tmp2, ISD::SETUGT);
3028    Tmp3 = DAG.getNode(ISD::FNEG, dl, VT, Tmp1);
3029    Tmp1 = DAG.getNode(ISD::SELECT, dl, VT, Tmp2, Tmp1, Tmp3);
3030    Results.push_back(Tmp1);
3031    break;
3032  }
3033  case ISD::FSQRT:
3034    Results.push_back(ExpandFPLibCall(Node, RTLIB::SQRT_F32, RTLIB::SQRT_F64,
3035                                      RTLIB::SQRT_F80, RTLIB::SQRT_PPCF128));
3036    break;
3037  case ISD::FSIN:
3038    Results.push_back(ExpandFPLibCall(Node, RTLIB::SIN_F32, RTLIB::SIN_F64,
3039                                      RTLIB::SIN_F80, RTLIB::SIN_PPCF128));
3040    break;
3041  case ISD::FCOS:
3042    Results.push_back(ExpandFPLibCall(Node, RTLIB::COS_F32, RTLIB::COS_F64,
3043                                      RTLIB::COS_F80, RTLIB::COS_PPCF128));
3044    break;
3045  case ISD::FLOG:
3046    Results.push_back(ExpandFPLibCall(Node, RTLIB::LOG_F32, RTLIB::LOG_F64,
3047                                      RTLIB::LOG_F80, RTLIB::LOG_PPCF128));
3048    break;
3049  case ISD::FLOG2:
3050    Results.push_back(ExpandFPLibCall(Node, RTLIB::LOG2_F32, RTLIB::LOG2_F64,
3051                                      RTLIB::LOG2_F80, RTLIB::LOG2_PPCF128));
3052    break;
3053  case ISD::FLOG10:
3054    Results.push_back(ExpandFPLibCall(Node, RTLIB::LOG10_F32, RTLIB::LOG10_F64,
3055                                      RTLIB::LOG10_F80, RTLIB::LOG10_PPCF128));
3056    break;
3057  case ISD::FEXP:
3058    Results.push_back(ExpandFPLibCall(Node, RTLIB::EXP_F32, RTLIB::EXP_F64,
3059                                      RTLIB::EXP_F80, RTLIB::EXP_PPCF128));
3060    break;
3061  case ISD::FEXP2:
3062    Results.push_back(ExpandFPLibCall(Node, RTLIB::EXP2_F32, RTLIB::EXP2_F64,
3063                                      RTLIB::EXP2_F80, RTLIB::EXP2_PPCF128));
3064    break;
3065  case ISD::FTRUNC:
3066    Results.push_back(ExpandFPLibCall(Node, RTLIB::TRUNC_F32, RTLIB::TRUNC_F64,
3067                                      RTLIB::TRUNC_F80, RTLIB::TRUNC_PPCF128));
3068    break;
3069  case ISD::FFLOOR:
3070    Results.push_back(ExpandFPLibCall(Node, RTLIB::FLOOR_F32, RTLIB::FLOOR_F64,
3071                                      RTLIB::FLOOR_F80, RTLIB::FLOOR_PPCF128));
3072    break;
3073  case ISD::FCEIL:
3074    Results.push_back(ExpandFPLibCall(Node, RTLIB::CEIL_F32, RTLIB::CEIL_F64,
3075                                      RTLIB::CEIL_F80, RTLIB::CEIL_PPCF128));
3076    break;
3077  case ISD::FRINT:
3078    Results.push_back(ExpandFPLibCall(Node, RTLIB::RINT_F32, RTLIB::RINT_F64,
3079                                      RTLIB::RINT_F80, RTLIB::RINT_PPCF128));
3080    break;
3081  case ISD::FNEARBYINT:
3082    Results.push_back(ExpandFPLibCall(Node, RTLIB::NEARBYINT_F32,
3083                                      RTLIB::NEARBYINT_F64,
3084                                      RTLIB::NEARBYINT_F80,
3085                                      RTLIB::NEARBYINT_PPCF128));
3086    break;
3087  case ISD::FPOWI:
3088    Results.push_back(ExpandFPLibCall(Node, RTLIB::POWI_F32, RTLIB::POWI_F64,
3089                                      RTLIB::POWI_F80, RTLIB::POWI_PPCF128));
3090    break;
3091  case ISD::FPOW:
3092    Results.push_back(ExpandFPLibCall(Node, RTLIB::POW_F32, RTLIB::POW_F64,
3093                                      RTLIB::POW_F80, RTLIB::POW_PPCF128));
3094    break;
3095  case ISD::FDIV:
3096    Results.push_back(ExpandFPLibCall(Node, RTLIB::DIV_F32, RTLIB::DIV_F64,
3097                                      RTLIB::DIV_F80, RTLIB::DIV_PPCF128));
3098    break;
3099  case ISD::FREM:
3100    Results.push_back(ExpandFPLibCall(Node, RTLIB::REM_F32, RTLIB::REM_F64,
3101                                      RTLIB::REM_F80, RTLIB::REM_PPCF128));
3102    break;
3103  case ISD::FMA:
3104    Results.push_back(ExpandFPLibCall(Node, RTLIB::FMA_F32, RTLIB::FMA_F64,
3105                                      RTLIB::FMA_F80, RTLIB::FMA_PPCF128));
3106    break;
3107  case ISD::FP16_TO_FP32:
3108    Results.push_back(ExpandLibCall(RTLIB::FPEXT_F16_F32, Node, false));
3109    break;
3110  case ISD::FP32_TO_FP16:
3111    Results.push_back(ExpandLibCall(RTLIB::FPROUND_F32_F16, Node, false));
3112    break;
3113  case ISD::ConstantFP: {
3114    ConstantFPSDNode *CFP = cast<ConstantFPSDNode>(Node);
3115    // Check to see if this FP immediate is already legal.
3116    // If this is a legal constant, turn it into a TargetConstantFP node.
3117    if (!TLI.isFPImmLegal(CFP->getValueAPF(), Node->getValueType(0)))
3118      Results.push_back(ExpandConstantFP(CFP, true));
3119    break;
3120  }
3121  case ISD::EHSELECTION: {
3122    unsigned Reg = TLI.getExceptionSelectorRegister();
3123    assert(Reg && "Can't expand to unknown register!");
3124    Results.push_back(DAG.getCopyFromReg(Node->getOperand(1), dl, Reg,
3125                                         Node->getValueType(0)));
3126    Results.push_back(Results[0].getValue(1));
3127    break;
3128  }
3129  case ISD::EXCEPTIONADDR: {
3130    unsigned Reg = TLI.getExceptionPointerRegister();
3131    assert(Reg && "Can't expand to unknown register!");
3132    Results.push_back(DAG.getCopyFromReg(Node->getOperand(0), dl, Reg,
3133                                         Node->getValueType(0)));
3134    Results.push_back(Results[0].getValue(1));
3135    break;
3136  }
3137  case ISD::FSUB: {
3138    EVT VT = Node->getValueType(0);
3139    assert(TLI.isOperationLegalOrCustom(ISD::FADD, VT) &&
3140           TLI.isOperationLegalOrCustom(ISD::FNEG, VT) &&
3141           "Don't know how to expand this FP subtraction!");
3142    Tmp1 = DAG.getNode(ISD::FNEG, dl, VT, Node->getOperand(1));
3143    Tmp1 = DAG.getNode(ISD::FADD, dl, VT, Node->getOperand(0), Tmp1);
3144    Results.push_back(Tmp1);
3145    break;
3146  }
3147  case ISD::SUB: {
3148    EVT VT = Node->getValueType(0);
3149    assert(TLI.isOperationLegalOrCustom(ISD::ADD, VT) &&
3150           TLI.isOperationLegalOrCustom(ISD::XOR, VT) &&
3151           "Don't know how to expand this subtraction!");
3152    Tmp1 = DAG.getNode(ISD::XOR, dl, VT, Node->getOperand(1),
3153               DAG.getConstant(APInt::getAllOnesValue(VT.getSizeInBits()), VT));
3154    Tmp1 = DAG.getNode(ISD::ADD, dl, VT, Tmp1, DAG.getConstant(1, VT));
3155    Results.push_back(DAG.getNode(ISD::ADD, dl, VT, Node->getOperand(0), Tmp1));
3156    break;
3157  }
3158  case ISD::UREM:
3159  case ISD::SREM: {
3160    EVT VT = Node->getValueType(0);
3161    SDVTList VTs = DAG.getVTList(VT, VT);
3162    bool isSigned = Node->getOpcode() == ISD::SREM;
3163    unsigned DivOpc = isSigned ? ISD::SDIV : ISD::UDIV;
3164    unsigned DivRemOpc = isSigned ? ISD::SDIVREM : ISD::UDIVREM;
3165    Tmp2 = Node->getOperand(0);
3166    Tmp3 = Node->getOperand(1);
3167    if (TLI.isOperationLegalOrCustom(DivRemOpc, VT) ||
3168        (isDivRemLibcallAvailable(Node, isSigned, TLI) &&
3169         // If div is legal, it's better to do the normal expansion
3170         !TLI.isOperationLegalOrCustom(DivOpc, Node->getValueType(0)) &&
3171         useDivRem(Node, isSigned, false))) {
3172      Tmp1 = DAG.getNode(DivRemOpc, dl, VTs, Tmp2, Tmp3).getValue(1);
3173    } else if (TLI.isOperationLegalOrCustom(DivOpc, VT)) {
3174      // X % Y -> X-X/Y*Y
3175      Tmp1 = DAG.getNode(DivOpc, dl, VT, Tmp2, Tmp3);
3176      Tmp1 = DAG.getNode(ISD::MUL, dl, VT, Tmp1, Tmp3);
3177      Tmp1 = DAG.getNode(ISD::SUB, dl, VT, Tmp2, Tmp1);
3178    } else if (isSigned)
3179      Tmp1 = ExpandIntLibCall(Node, true,
3180                              RTLIB::SREM_I8,
3181                              RTLIB::SREM_I16, RTLIB::SREM_I32,
3182                              RTLIB::SREM_I64, RTLIB::SREM_I128);
3183    else
3184      Tmp1 = ExpandIntLibCall(Node, false,
3185                              RTLIB::UREM_I8,
3186                              RTLIB::UREM_I16, RTLIB::UREM_I32,
3187                              RTLIB::UREM_I64, RTLIB::UREM_I128);
3188    Results.push_back(Tmp1);
3189    break;
3190  }
3191  case ISD::UDIV:
3192  case ISD::SDIV: {
3193    bool isSigned = Node->getOpcode() == ISD::SDIV;
3194    unsigned DivRemOpc = isSigned ? ISD::SDIVREM : ISD::UDIVREM;
3195    EVT VT = Node->getValueType(0);
3196    SDVTList VTs = DAG.getVTList(VT, VT);
3197    if (TLI.isOperationLegalOrCustom(DivRemOpc, VT) ||
3198        (isDivRemLibcallAvailable(Node, isSigned, TLI) &&
3199         useDivRem(Node, isSigned, true)))
3200      Tmp1 = DAG.getNode(DivRemOpc, dl, VTs, Node->getOperand(0),
3201                         Node->getOperand(1));
3202    else if (isSigned)
3203      Tmp1 = ExpandIntLibCall(Node, true,
3204                              RTLIB::SDIV_I8,
3205                              RTLIB::SDIV_I16, RTLIB::SDIV_I32,
3206                              RTLIB::SDIV_I64, RTLIB::SDIV_I128);
3207    else
3208      Tmp1 = ExpandIntLibCall(Node, false,
3209                              RTLIB::UDIV_I8,
3210                              RTLIB::UDIV_I16, RTLIB::UDIV_I32,
3211                              RTLIB::UDIV_I64, RTLIB::UDIV_I128);
3212    Results.push_back(Tmp1);
3213    break;
3214  }
3215  case ISD::MULHU:
3216  case ISD::MULHS: {
3217    unsigned ExpandOpcode = Node->getOpcode() == ISD::MULHU ? ISD::UMUL_LOHI :
3218                                                              ISD::SMUL_LOHI;
3219    EVT VT = Node->getValueType(0);
3220    SDVTList VTs = DAG.getVTList(VT, VT);
3221    assert(TLI.isOperationLegalOrCustom(ExpandOpcode, VT) &&
3222           "If this wasn't legal, it shouldn't have been created!");
3223    Tmp1 = DAG.getNode(ExpandOpcode, dl, VTs, Node->getOperand(0),
3224                       Node->getOperand(1));
3225    Results.push_back(Tmp1.getValue(1));
3226    break;
3227  }
3228  case ISD::SDIVREM:
3229  case ISD::UDIVREM:
3230    // Expand into divrem libcall
3231    ExpandDivRemLibCall(Node, Results);
3232    break;
3233  case ISD::MUL: {
3234    EVT VT = Node->getValueType(0);
3235    SDVTList VTs = DAG.getVTList(VT, VT);
3236    // See if multiply or divide can be lowered using two-result operations.
3237    // We just need the low half of the multiply; try both the signed
3238    // and unsigned forms. If the target supports both SMUL_LOHI and
3239    // UMUL_LOHI, form a preference by checking which forms of plain
3240    // MULH it supports.
3241    bool HasSMUL_LOHI = TLI.isOperationLegalOrCustom(ISD::SMUL_LOHI, VT);
3242    bool HasUMUL_LOHI = TLI.isOperationLegalOrCustom(ISD::UMUL_LOHI, VT);
3243    bool HasMULHS = TLI.isOperationLegalOrCustom(ISD::MULHS, VT);
3244    bool HasMULHU = TLI.isOperationLegalOrCustom(ISD::MULHU, VT);
3245    unsigned OpToUse = 0;
3246    if (HasSMUL_LOHI && !HasMULHS) {
3247      OpToUse = ISD::SMUL_LOHI;
3248    } else if (HasUMUL_LOHI && !HasMULHU) {
3249      OpToUse = ISD::UMUL_LOHI;
3250    } else if (HasSMUL_LOHI) {
3251      OpToUse = ISD::SMUL_LOHI;
3252    } else if (HasUMUL_LOHI) {
3253      OpToUse = ISD::UMUL_LOHI;
3254    }
3255    if (OpToUse) {
3256      Results.push_back(DAG.getNode(OpToUse, dl, VTs, Node->getOperand(0),
3257                                    Node->getOperand(1)));
3258      break;
3259    }
3260    Tmp1 = ExpandIntLibCall(Node, false,
3261                            RTLIB::MUL_I8,
3262                            RTLIB::MUL_I16, RTLIB::MUL_I32,
3263                            RTLIB::MUL_I64, RTLIB::MUL_I128);
3264    Results.push_back(Tmp1);
3265    break;
3266  }
3267  case ISD::SADDO:
3268  case ISD::SSUBO: {
3269    SDValue LHS = Node->getOperand(0);
3270    SDValue RHS = Node->getOperand(1);
3271    SDValue Sum = DAG.getNode(Node->getOpcode() == ISD::SADDO ?
3272                              ISD::ADD : ISD::SUB, dl, LHS.getValueType(),
3273                              LHS, RHS);
3274    Results.push_back(Sum);
3275    EVT OType = Node->getValueType(1);
3276
3277    SDValue Zero = DAG.getConstant(0, LHS.getValueType());
3278
3279    //   LHSSign -> LHS >= 0
3280    //   RHSSign -> RHS >= 0
3281    //   SumSign -> Sum >= 0
3282    //
3283    //   Add:
3284    //   Overflow -> (LHSSign == RHSSign) && (LHSSign != SumSign)
3285    //   Sub:
3286    //   Overflow -> (LHSSign != RHSSign) && (LHSSign != SumSign)
3287    //
3288    SDValue LHSSign = DAG.getSetCC(dl, OType, LHS, Zero, ISD::SETGE);
3289    SDValue RHSSign = DAG.getSetCC(dl, OType, RHS, Zero, ISD::SETGE);
3290    SDValue SignsMatch = DAG.getSetCC(dl, OType, LHSSign, RHSSign,
3291                                      Node->getOpcode() == ISD::SADDO ?
3292                                      ISD::SETEQ : ISD::SETNE);
3293
3294    SDValue SumSign = DAG.getSetCC(dl, OType, Sum, Zero, ISD::SETGE);
3295    SDValue SumSignNE = DAG.getSetCC(dl, OType, LHSSign, SumSign, ISD::SETNE);
3296
3297    SDValue Cmp = DAG.getNode(ISD::AND, dl, OType, SignsMatch, SumSignNE);
3298    Results.push_back(Cmp);
3299    break;
3300  }
3301  case ISD::UADDO:
3302  case ISD::USUBO: {
3303    SDValue LHS = Node->getOperand(0);
3304    SDValue RHS = Node->getOperand(1);
3305    SDValue Sum = DAG.getNode(Node->getOpcode() == ISD::UADDO ?
3306                              ISD::ADD : ISD::SUB, dl, LHS.getValueType(),
3307                              LHS, RHS);
3308    Results.push_back(Sum);
3309    Results.push_back(DAG.getSetCC(dl, Node->getValueType(1), Sum, LHS,
3310                                   Node->getOpcode () == ISD::UADDO ?
3311                                   ISD::SETULT : ISD::SETUGT));
3312    break;
3313  }
3314  case ISD::UMULO:
3315  case ISD::SMULO: {
3316    EVT VT = Node->getValueType(0);
3317    EVT WideVT = EVT::getIntegerVT(*DAG.getContext(), VT.getSizeInBits() * 2);
3318    SDValue LHS = Node->getOperand(0);
3319    SDValue RHS = Node->getOperand(1);
3320    SDValue BottomHalf;
3321    SDValue TopHalf;
3322    static const unsigned Ops[2][3] =
3323        { { ISD::MULHU, ISD::UMUL_LOHI, ISD::ZERO_EXTEND },
3324          { ISD::MULHS, ISD::SMUL_LOHI, ISD::SIGN_EXTEND }};
3325    bool isSigned = Node->getOpcode() == ISD::SMULO;
3326    if (TLI.isOperationLegalOrCustom(Ops[isSigned][0], VT)) {
3327      BottomHalf = DAG.getNode(ISD::MUL, dl, VT, LHS, RHS);
3328      TopHalf = DAG.getNode(Ops[isSigned][0], dl, VT, LHS, RHS);
3329    } else if (TLI.isOperationLegalOrCustom(Ops[isSigned][1], VT)) {
3330      BottomHalf = DAG.getNode(Ops[isSigned][1], dl, DAG.getVTList(VT, VT), LHS,
3331                               RHS);
3332      TopHalf = BottomHalf.getValue(1);
3333    } else if (TLI.isTypeLegal(EVT::getIntegerVT(*DAG.getContext(),
3334                                                 VT.getSizeInBits() * 2))) {
3335      LHS = DAG.getNode(Ops[isSigned][2], dl, WideVT, LHS);
3336      RHS = DAG.getNode(Ops[isSigned][2], dl, WideVT, RHS);
3337      Tmp1 = DAG.getNode(ISD::MUL, dl, WideVT, LHS, RHS);
3338      BottomHalf = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, VT, Tmp1,
3339                               DAG.getIntPtrConstant(0));
3340      TopHalf = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, VT, Tmp1,
3341                            DAG.getIntPtrConstant(1));
3342    } else {
3343      // We can fall back to a libcall with an illegal type for the MUL if we
3344      // have a libcall big enough.
3345      // Also, we can fall back to a division in some cases, but that's a big
3346      // performance hit in the general case.
3347      RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
3348      if (WideVT == MVT::i16)
3349        LC = RTLIB::MUL_I16;
3350      else if (WideVT == MVT::i32)
3351        LC = RTLIB::MUL_I32;
3352      else if (WideVT == MVT::i64)
3353        LC = RTLIB::MUL_I64;
3354      else if (WideVT == MVT::i128)
3355        LC = RTLIB::MUL_I128;
3356      assert(LC != RTLIB::UNKNOWN_LIBCALL && "Cannot expand this operation!");
3357
3358      // The high part is obtained by SRA'ing all but one of the bits of low
3359      // part.
3360      unsigned LoSize = VT.getSizeInBits();
3361      SDValue HiLHS = DAG.getNode(ISD::SRA, dl, VT, RHS,
3362                                DAG.getConstant(LoSize-1, TLI.getPointerTy()));
3363      SDValue HiRHS = DAG.getNode(ISD::SRA, dl, VT, LHS,
3364                                DAG.getConstant(LoSize-1, TLI.getPointerTy()));
3365
3366      // Here we're passing the 2 arguments explicitly as 4 arguments that are
3367      // pre-lowered to the correct types. This all depends upon WideVT not
3368      // being a legal type for the architecture and thus has to be split to
3369      // two arguments.
3370      SDValue Args[] = { LHS, HiLHS, RHS, HiRHS };
3371      SDValue Ret = ExpandLibCall(LC, WideVT, Args, 4, isSigned, dl);
3372      BottomHalf = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, VT, Ret,
3373                               DAG.getIntPtrConstant(0));
3374      TopHalf = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, VT, Ret,
3375                            DAG.getIntPtrConstant(1));
3376      // Ret is a node with an illegal type. Because such things are not
3377      // generally permitted during this phase of legalization, delete the
3378      // node. The above EXTRACT_ELEMENT nodes should have been folded.
3379      DAG.DeleteNode(Ret.getNode());
3380    }
3381
3382    if (isSigned) {
3383      Tmp1 = DAG.getConstant(VT.getSizeInBits() - 1,
3384                             TLI.getShiftAmountTy(BottomHalf.getValueType()));
3385      Tmp1 = DAG.getNode(ISD::SRA, dl, VT, BottomHalf, Tmp1);
3386      TopHalf = DAG.getSetCC(dl, TLI.getSetCCResultType(VT), TopHalf, Tmp1,
3387                             ISD::SETNE);
3388    } else {
3389      TopHalf = DAG.getSetCC(dl, TLI.getSetCCResultType(VT), TopHalf,
3390                             DAG.getConstant(0, VT), ISD::SETNE);
3391    }
3392    Results.push_back(BottomHalf);
3393    Results.push_back(TopHalf);
3394    break;
3395  }
3396  case ISD::BUILD_PAIR: {
3397    EVT PairTy = Node->getValueType(0);
3398    Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, PairTy, Node->getOperand(0));
3399    Tmp2 = DAG.getNode(ISD::ANY_EXTEND, dl, PairTy, Node->getOperand(1));
3400    Tmp2 = DAG.getNode(ISD::SHL, dl, PairTy, Tmp2,
3401                       DAG.getConstant(PairTy.getSizeInBits()/2,
3402                                       TLI.getShiftAmountTy(PairTy)));
3403    Results.push_back(DAG.getNode(ISD::OR, dl, PairTy, Tmp1, Tmp2));
3404    break;
3405  }
3406  case ISD::SELECT:
3407    Tmp1 = Node->getOperand(0);
3408    Tmp2 = Node->getOperand(1);
3409    Tmp3 = Node->getOperand(2);
3410    if (Tmp1.getOpcode() == ISD::SETCC) {
3411      Tmp1 = DAG.getSelectCC(dl, Tmp1.getOperand(0), Tmp1.getOperand(1),
3412                             Tmp2, Tmp3,
3413                             cast<CondCodeSDNode>(Tmp1.getOperand(2))->get());
3414    } else {
3415      Tmp1 = DAG.getSelectCC(dl, Tmp1,
3416                             DAG.getConstant(0, Tmp1.getValueType()),
3417                             Tmp2, Tmp3, ISD::SETNE);
3418    }
3419    Results.push_back(Tmp1);
3420    break;
3421  case ISD::BR_JT: {
3422    SDValue Chain = Node->getOperand(0);
3423    SDValue Table = Node->getOperand(1);
3424    SDValue Index = Node->getOperand(2);
3425
3426    EVT PTy = TLI.getPointerTy();
3427
3428    const DataLayout &TD = *TLI.getDataLayout();
3429    unsigned EntrySize =
3430      DAG.getMachineFunction().getJumpTableInfo()->getEntrySize(TD);
3431
3432    Index = DAG.getNode(ISD::MUL, dl, PTy,
3433                        Index, DAG.getConstant(EntrySize, PTy));
3434    SDValue Addr = DAG.getNode(ISD::ADD, dl, PTy, Index, Table);
3435
3436    EVT MemVT = EVT::getIntegerVT(*DAG.getContext(), EntrySize * 8);
3437    SDValue LD = DAG.getExtLoad(ISD::SEXTLOAD, dl, PTy, Chain, Addr,
3438                                MachinePointerInfo::getJumpTable(), MemVT,
3439                                false, false, 0);
3440    Addr = LD;
3441    if (TM.getRelocationModel() == Reloc::PIC_) {
3442      // For PIC, the sequence is:
3443      // BRIND(load(Jumptable + index) + RelocBase)
3444      // RelocBase can be JumpTable, GOT or some sort of global base.
3445      Addr = DAG.getNode(ISD::ADD, dl, PTy, Addr,
3446                          TLI.getPICJumpTableRelocBase(Table, DAG));
3447    }
3448    Tmp1 = DAG.getNode(ISD::BRIND, dl, MVT::Other, LD.getValue(1), Addr);
3449    Results.push_back(Tmp1);
3450    break;
3451  }
3452  case ISD::BRCOND:
3453    // Expand brcond's setcc into its constituent parts and create a BR_CC
3454    // Node.
3455    Tmp1 = Node->getOperand(0);
3456    Tmp2 = Node->getOperand(1);
3457    if (Tmp2.getOpcode() == ISD::SETCC) {
3458      Tmp1 = DAG.getNode(ISD::BR_CC, dl, MVT::Other,
3459                         Tmp1, Tmp2.getOperand(2),
3460                         Tmp2.getOperand(0), Tmp2.getOperand(1),
3461                         Node->getOperand(2));
3462    } else {
3463      // We test only the i1 bit.  Skip the AND if UNDEF.
3464      Tmp3 = (Tmp2.getOpcode() == ISD::UNDEF) ? Tmp2 :
3465        DAG.getNode(ISD::AND, dl, Tmp2.getValueType(), Tmp2,
3466                    DAG.getConstant(1, Tmp2.getValueType()));
3467      Tmp1 = DAG.getNode(ISD::BR_CC, dl, MVT::Other, Tmp1,
3468                         DAG.getCondCode(ISD::SETNE), Tmp3,
3469                         DAG.getConstant(0, Tmp3.getValueType()),
3470                         Node->getOperand(2));
3471    }
3472    Results.push_back(Tmp1);
3473    break;
3474  case ISD::SETCC: {
3475    Tmp1 = Node->getOperand(0);
3476    Tmp2 = Node->getOperand(1);
3477    Tmp3 = Node->getOperand(2);
3478    LegalizeSetCCCondCode(Node->getValueType(0), Tmp1, Tmp2, Tmp3, dl);
3479
3480    // If we expanded the SETCC into an AND/OR, return the new node
3481    if (Tmp2.getNode() == 0) {
3482      Results.push_back(Tmp1);
3483      break;
3484    }
3485
3486    // Otherwise, SETCC for the given comparison type must be completely
3487    // illegal; expand it into a SELECT_CC.
3488    EVT VT = Node->getValueType(0);
3489    Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, VT, Tmp1, Tmp2,
3490                       DAG.getConstant(1, VT), DAG.getConstant(0, VT), Tmp3);
3491    Results.push_back(Tmp1);
3492    break;
3493  }
3494  case ISD::SELECT_CC: {
3495    Tmp1 = Node->getOperand(0);   // LHS
3496    Tmp2 = Node->getOperand(1);   // RHS
3497    Tmp3 = Node->getOperand(2);   // True
3498    Tmp4 = Node->getOperand(3);   // False
3499    SDValue CC = Node->getOperand(4);
3500
3501    LegalizeSetCCCondCode(TLI.getSetCCResultType(Tmp1.getValueType()),
3502                          Tmp1, Tmp2, CC, dl);
3503
3504    assert(!Tmp2.getNode() && "Can't legalize SELECT_CC with legal condition!");
3505    Tmp2 = DAG.getConstant(0, Tmp1.getValueType());
3506    CC = DAG.getCondCode(ISD::SETNE);
3507    Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, Node->getValueType(0), Tmp1, Tmp2,
3508                       Tmp3, Tmp4, CC);
3509    Results.push_back(Tmp1);
3510    break;
3511  }
3512  case ISD::BR_CC: {
3513    Tmp1 = Node->getOperand(0);              // Chain
3514    Tmp2 = Node->getOperand(2);              // LHS
3515    Tmp3 = Node->getOperand(3);              // RHS
3516    Tmp4 = Node->getOperand(1);              // CC
3517
3518    LegalizeSetCCCondCode(TLI.getSetCCResultType(Tmp2.getValueType()),
3519                          Tmp2, Tmp3, Tmp4, dl);
3520
3521    assert(!Tmp3.getNode() && "Can't legalize BR_CC with legal condition!");
3522    Tmp3 = DAG.getConstant(0, Tmp2.getValueType());
3523    Tmp4 = DAG.getCondCode(ISD::SETNE);
3524    Tmp1 = DAG.getNode(ISD::BR_CC, dl, Node->getValueType(0), Tmp1, Tmp4, Tmp2,
3525                       Tmp3, Node->getOperand(4));
3526    Results.push_back(Tmp1);
3527    break;
3528  }
3529  case ISD::BUILD_VECTOR:
3530    Results.push_back(ExpandBUILD_VECTOR(Node));
3531    break;
3532  case ISD::SRA:
3533  case ISD::SRL:
3534  case ISD::SHL: {
3535    // Scalarize vector SRA/SRL/SHL.
3536    EVT VT = Node->getValueType(0);
3537    assert(VT.isVector() && "Unable to legalize non-vector shift");
3538    assert(TLI.isTypeLegal(VT.getScalarType())&& "Element type must be legal");
3539    unsigned NumElem = VT.getVectorNumElements();
3540
3541    SmallVector<SDValue, 8> Scalars;
3542    for (unsigned Idx = 0; Idx < NumElem; Idx++) {
3543      SDValue Ex = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl,
3544                               VT.getScalarType(),
3545                               Node->getOperand(0), DAG.getIntPtrConstant(Idx));
3546      SDValue Sh = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl,
3547                               VT.getScalarType(),
3548                               Node->getOperand(1), DAG.getIntPtrConstant(Idx));
3549      Scalars.push_back(DAG.getNode(Node->getOpcode(), dl,
3550                                    VT.getScalarType(), Ex, Sh));
3551    }
3552    SDValue Result =
3553      DAG.getNode(ISD::BUILD_VECTOR, dl, Node->getValueType(0),
3554                  &Scalars[0], Scalars.size());
3555    ReplaceNode(SDValue(Node, 0), Result);
3556    break;
3557  }
3558  case ISD::GLOBAL_OFFSET_TABLE:
3559  case ISD::GlobalAddress:
3560  case ISD::GlobalTLSAddress:
3561  case ISD::ExternalSymbol:
3562  case ISD::ConstantPool:
3563  case ISD::JumpTable:
3564  case ISD::INTRINSIC_W_CHAIN:
3565  case ISD::INTRINSIC_WO_CHAIN:
3566  case ISD::INTRINSIC_VOID:
3567    // FIXME: Custom lowering for these operations shouldn't return null!
3568    break;
3569  }
3570
3571  // Replace the original node with the legalized result.
3572  if (!Results.empty())
3573    ReplaceNode(Node, Results.data());
3574}
3575
3576void SelectionDAGLegalize::PromoteNode(SDNode *Node) {
3577  SmallVector<SDValue, 8> Results;
3578  EVT OVT = Node->getValueType(0);
3579  if (Node->getOpcode() == ISD::UINT_TO_FP ||
3580      Node->getOpcode() == ISD::SINT_TO_FP ||
3581      Node->getOpcode() == ISD::SETCC) {
3582    OVT = Node->getOperand(0).getValueType();
3583  }
3584  EVT NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), OVT);
3585  DebugLoc dl = Node->getDebugLoc();
3586  SDValue Tmp1, Tmp2, Tmp3;
3587  switch (Node->getOpcode()) {
3588  case ISD::CTTZ:
3589  case ISD::CTTZ_ZERO_UNDEF:
3590  case ISD::CTLZ:
3591  case ISD::CTLZ_ZERO_UNDEF:
3592  case ISD::CTPOP:
3593    // Zero extend the argument.
3594    Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, NVT, Node->getOperand(0));
3595    // Perform the larger operation. For CTPOP and CTTZ_ZERO_UNDEF, this is
3596    // already the correct result.
3597    Tmp1 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1);
3598    if (Node->getOpcode() == ISD::CTTZ) {
3599      // FIXME: This should set a bit in the zero extended value instead.
3600      Tmp2 = DAG.getSetCC(dl, TLI.getSetCCResultType(NVT),
3601                          Tmp1, DAG.getConstant(NVT.getSizeInBits(), NVT),
3602                          ISD::SETEQ);
3603      Tmp1 = DAG.getNode(ISD::SELECT, dl, NVT, Tmp2,
3604                          DAG.getConstant(OVT.getSizeInBits(), NVT), Tmp1);
3605    } else if (Node->getOpcode() == ISD::CTLZ ||
3606               Node->getOpcode() == ISD::CTLZ_ZERO_UNDEF) {
3607      // Tmp1 = Tmp1 - (sizeinbits(NVT) - sizeinbits(Old VT))
3608      Tmp1 = DAG.getNode(ISD::SUB, dl, NVT, Tmp1,
3609                          DAG.getConstant(NVT.getSizeInBits() -
3610                                          OVT.getSizeInBits(), NVT));
3611    }
3612    Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp1));
3613    break;
3614  case ISD::BSWAP: {
3615    unsigned DiffBits = NVT.getSizeInBits() - OVT.getSizeInBits();
3616    Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, NVT, Node->getOperand(0));
3617    Tmp1 = DAG.getNode(ISD::BSWAP, dl, NVT, Tmp1);
3618    Tmp1 = DAG.getNode(ISD::SRL, dl, NVT, Tmp1,
3619                          DAG.getConstant(DiffBits, TLI.getShiftAmountTy(NVT)));
3620    Results.push_back(Tmp1);
3621    break;
3622  }
3623  case ISD::FP_TO_UINT:
3624  case ISD::FP_TO_SINT:
3625    Tmp1 = PromoteLegalFP_TO_INT(Node->getOperand(0), Node->getValueType(0),
3626                                 Node->getOpcode() == ISD::FP_TO_SINT, dl);
3627    Results.push_back(Tmp1);
3628    break;
3629  case ISD::UINT_TO_FP:
3630  case ISD::SINT_TO_FP:
3631    Tmp1 = PromoteLegalINT_TO_FP(Node->getOperand(0), Node->getValueType(0),
3632                                 Node->getOpcode() == ISD::SINT_TO_FP, dl);
3633    Results.push_back(Tmp1);
3634    break;
3635  case ISD::VAARG: {
3636    SDValue Chain = Node->getOperand(0); // Get the chain.
3637    SDValue Ptr = Node->getOperand(1); // Get the pointer.
3638
3639    unsigned TruncOp;
3640    if (OVT.isVector()) {
3641      TruncOp = ISD::BITCAST;
3642    } else {
3643      assert(OVT.isInteger()
3644        && "VAARG promotion is supported only for vectors or integer types");
3645      TruncOp = ISD::TRUNCATE;
3646    }
3647
3648    // Perform the larger operation, then convert back
3649    Tmp1 = DAG.getVAArg(NVT, dl, Chain, Ptr, Node->getOperand(2),
3650             Node->getConstantOperandVal(3));
3651    Chain = Tmp1.getValue(1);
3652
3653    Tmp2 = DAG.getNode(TruncOp, dl, OVT, Tmp1);
3654
3655    // Modified the chain result - switch anything that used the old chain to
3656    // use the new one.
3657    DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 0), Tmp2);
3658    DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 1), Chain);
3659    ReplacedNode(Node);
3660    break;
3661  }
3662  case ISD::AND:
3663  case ISD::OR:
3664  case ISD::XOR: {
3665    unsigned ExtOp, TruncOp;
3666    if (OVT.isVector()) {
3667      ExtOp   = ISD::BITCAST;
3668      TruncOp = ISD::BITCAST;
3669    } else {
3670      assert(OVT.isInteger() && "Cannot promote logic operation");
3671      ExtOp   = ISD::ANY_EXTEND;
3672      TruncOp = ISD::TRUNCATE;
3673    }
3674    // Promote each of the values to the new type.
3675    Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(0));
3676    Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
3677    // Perform the larger operation, then convert back
3678    Tmp1 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2);
3679    Results.push_back(DAG.getNode(TruncOp, dl, OVT, Tmp1));
3680    break;
3681  }
3682  case ISD::SELECT: {
3683    unsigned ExtOp, TruncOp;
3684    if (Node->getValueType(0).isVector()) {
3685      ExtOp   = ISD::BITCAST;
3686      TruncOp = ISD::BITCAST;
3687    } else if (Node->getValueType(0).isInteger()) {
3688      ExtOp   = ISD::ANY_EXTEND;
3689      TruncOp = ISD::TRUNCATE;
3690    } else {
3691      ExtOp   = ISD::FP_EXTEND;
3692      TruncOp = ISD::FP_ROUND;
3693    }
3694    Tmp1 = Node->getOperand(0);
3695    // Promote each of the values to the new type.
3696    Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
3697    Tmp3 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(2));
3698    // Perform the larger operation, then round down.
3699    Tmp1 = DAG.getNode(ISD::SELECT, dl, NVT, Tmp1, Tmp2, Tmp3);
3700    if (TruncOp != ISD::FP_ROUND)
3701      Tmp1 = DAG.getNode(TruncOp, dl, Node->getValueType(0), Tmp1);
3702    else
3703      Tmp1 = DAG.getNode(TruncOp, dl, Node->getValueType(0), Tmp1,
3704                         DAG.getIntPtrConstant(0));
3705    Results.push_back(Tmp1);
3706    break;
3707  }
3708  case ISD::VECTOR_SHUFFLE: {
3709    ArrayRef<int> Mask = cast<ShuffleVectorSDNode>(Node)->getMask();
3710
3711    // Cast the two input vectors.
3712    Tmp1 = DAG.getNode(ISD::BITCAST, dl, NVT, Node->getOperand(0));
3713    Tmp2 = DAG.getNode(ISD::BITCAST, dl, NVT, Node->getOperand(1));
3714
3715    // Convert the shuffle mask to the right # elements.
3716    Tmp1 = ShuffleWithNarrowerEltType(NVT, OVT, dl, Tmp1, Tmp2, Mask);
3717    Tmp1 = DAG.getNode(ISD::BITCAST, dl, OVT, Tmp1);
3718    Results.push_back(Tmp1);
3719    break;
3720  }
3721  case ISD::SETCC: {
3722    unsigned ExtOp = ISD::FP_EXTEND;
3723    if (NVT.isInteger()) {
3724      ISD::CondCode CCCode =
3725        cast<CondCodeSDNode>(Node->getOperand(2))->get();
3726      ExtOp = isSignedIntSetCC(CCCode) ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND;
3727    }
3728    Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(0));
3729    Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
3730    Results.push_back(DAG.getNode(ISD::SETCC, dl, Node->getValueType(0),
3731                                  Tmp1, Tmp2, Node->getOperand(2)));
3732    break;
3733  }
3734  case ISD::FDIV:
3735  case ISD::FREM:
3736  case ISD::FPOW: {
3737    Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(0));
3738    Tmp2 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(1));
3739    Tmp3 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2);
3740    Results.push_back(DAG.getNode(ISD::FP_ROUND, dl, OVT,
3741                                  Tmp3, DAG.getIntPtrConstant(0)));
3742    break;
3743  }
3744  case ISD::FLOG2:
3745  case ISD::FEXP2:
3746  case ISD::FLOG:
3747  case ISD::FEXP: {
3748    Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(0));
3749    Tmp2 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1);
3750    Results.push_back(DAG.getNode(ISD::FP_ROUND, dl, OVT,
3751                                  Tmp2, DAG.getIntPtrConstant(0)));
3752    break;
3753  }
3754  }
3755
3756  // Replace the original node with the legalized result.
3757  if (!Results.empty())
3758    ReplaceNode(Node, Results.data());
3759}
3760
3761// SelectionDAG::Legalize - This is the entry point for the file.
3762//
3763void SelectionDAG::Legalize() {
3764  /// run - This is the main entry point to this class.
3765  ///
3766  SelectionDAGLegalize(*this).LegalizeDAG();
3767}
3768