LegalizeDAG.cpp revision 4f17f88071260cecffd96c272098549ac5887523
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/SmallPtrSet.h"
16#include "llvm/ADT/SmallVector.h"
17#include "llvm/ADT/Triple.h"
18#include "llvm/CodeGen/Analysis.h"
19#include "llvm/CodeGen/MachineFunction.h"
20#include "llvm/CodeGen/MachineJumpTableInfo.h"
21#include "llvm/DebugInfo.h"
22#include "llvm/IR/CallingConv.h"
23#include "llvm/IR/Constants.h"
24#include "llvm/IR/DataLayout.h"
25#include "llvm/IR/DerivedTypes.h"
26#include "llvm/IR/Function.h"
27#include "llvm/IR/LLVMContext.h"
28#include "llvm/Support/Debug.h"
29#include "llvm/Support/ErrorHandling.h"
30#include "llvm/Support/MathExtras.h"
31#include "llvm/Support/raw_ostream.h"
32#include "llvm/Target/TargetFrameLowering.h"
33#include "llvm/Target/TargetLowering.h"
34#include "llvm/Target/TargetMachine.h"
35using namespace llvm;
36
37//===----------------------------------------------------------------------===//
38/// SelectionDAGLegalize - This takes an arbitrary SelectionDAG as input and
39/// hacks on it until the target machine can handle it.  This involves
40/// eliminating value sizes the machine cannot handle (promoting small sizes to
41/// large sizes or splitting up large values into small values) as well as
42/// eliminating operations the machine cannot handle.
43///
44/// This code also does a small amount of optimization and recognition of idioms
45/// as part of its processing.  For example, if a target does not support a
46/// 'setcc' instruction efficiently, but does support 'brcc' instruction, this
47/// will attempt merge setcc and brc instructions into brcc's.
48///
49namespace {
50class SelectionDAGLegalize : public SelectionDAG::DAGUpdateListener {
51  const TargetMachine &TM;
52  const TargetLowering &TLI;
53  SelectionDAG &DAG;
54
55  /// LegalizePosition - The iterator for walking through the node list.
56  SelectionDAG::allnodes_iterator LegalizePosition;
57
58  /// LegalizedNodes - The set of nodes which have already been legalized.
59  SmallPtrSet<SDNode *, 16> LegalizedNodes;
60
61  EVT getSetCCResultType(EVT VT) const {
62    return TLI.getSetCCResultType(*DAG.getContext(), VT);
63  }
64
65  // Libcall insertion helpers.
66
67public:
68  explicit SelectionDAGLegalize(SelectionDAG &DAG);
69
70  void LegalizeDAG();
71
72private:
73  /// LegalizeOp - Legalizes the given operation.
74  void LegalizeOp(SDNode *Node);
75
76  SDValue OptimizeFloatStore(StoreSDNode *ST);
77
78  void LegalizeLoadOps(SDNode *Node);
79  void LegalizeStoreOps(SDNode *Node);
80
81  /// PerformInsertVectorEltInMemory - Some target cannot handle a variable
82  /// insertion index for the INSERT_VECTOR_ELT instruction.  In this case, it
83  /// is necessary to spill the vector being inserted into to memory, perform
84  /// the insert there, and then read the result back.
85  SDValue PerformInsertVectorEltInMemory(SDValue Vec, SDValue Val,
86                                         SDValue Idx, SDLoc dl);
87  SDValue ExpandINSERT_VECTOR_ELT(SDValue Vec, SDValue Val,
88                                  SDValue Idx, SDLoc dl);
89
90  /// ShuffleWithNarrowerEltType - Return a vector shuffle operation which
91  /// performs the same shuffe in terms of order or result bytes, but on a type
92  /// whose vector element type is narrower than the original shuffle type.
93  /// e.g. <v4i32> <0, 1, 0, 1> -> v8i16 <0, 1, 2, 3, 0, 1, 2, 3>
94  SDValue ShuffleWithNarrowerEltType(EVT NVT, EVT VT, SDLoc dl,
95                                     SDValue N1, SDValue N2,
96                                     ArrayRef<int> Mask) const;
97
98  bool LegalizeSetCCCondCode(EVT VT, SDValue &LHS, SDValue &RHS, SDValue &CC,
99                             SDLoc dl);
100
101  SDValue ExpandLibCall(RTLIB::Libcall LC, SDNode *Node, bool isSigned);
102  SDValue ExpandLibCall(RTLIB::Libcall LC, EVT RetVT, const SDValue *Ops,
103                        unsigned NumOps, bool isSigned, SDLoc dl);
104
105  std::pair<SDValue, SDValue> ExpandChainLibCall(RTLIB::Libcall LC,
106                                                 SDNode *Node, bool isSigned);
107  SDValue ExpandFPLibCall(SDNode *Node, RTLIB::Libcall Call_F32,
108                          RTLIB::Libcall Call_F64, RTLIB::Libcall Call_F80,
109                          RTLIB::Libcall Call_F128,
110                          RTLIB::Libcall Call_PPCF128);
111  SDValue ExpandIntLibCall(SDNode *Node, bool isSigned,
112                           RTLIB::Libcall Call_I8,
113                           RTLIB::Libcall Call_I16,
114                           RTLIB::Libcall Call_I32,
115                           RTLIB::Libcall Call_I64,
116                           RTLIB::Libcall Call_I128);
117  void ExpandDivRemLibCall(SDNode *Node, SmallVectorImpl<SDValue> &Results);
118  void ExpandSinCosLibCall(SDNode *Node, SmallVectorImpl<SDValue> &Results);
119
120  SDValue EmitStackConvert(SDValue SrcOp, EVT SlotVT, EVT DestVT, SDLoc dl);
121  SDValue ExpandBUILD_VECTOR(SDNode *Node);
122  SDValue ExpandSCALAR_TO_VECTOR(SDNode *Node);
123  void ExpandDYNAMIC_STACKALLOC(SDNode *Node,
124                                SmallVectorImpl<SDValue> &Results);
125  SDValue ExpandFCOPYSIGN(SDNode *Node);
126  SDValue ExpandLegalINT_TO_FP(bool isSigned, SDValue LegalOp, EVT DestVT,
127                               SDLoc dl);
128  SDValue PromoteLegalINT_TO_FP(SDValue LegalOp, EVT DestVT, bool isSigned,
129                                SDLoc dl);
130  SDValue PromoteLegalFP_TO_INT(SDValue LegalOp, EVT DestVT, bool isSigned,
131                                SDLoc dl);
132
133  SDValue ExpandBSWAP(SDValue Op, SDLoc dl);
134  SDValue ExpandBitCount(unsigned Opc, SDValue Op, SDLoc dl);
135
136  SDValue ExpandExtractFromVectorThroughStack(SDValue Op);
137  SDValue ExpandInsertToVectorThroughStack(SDValue Op);
138  SDValue ExpandVectorBuildThroughStack(SDNode* Node);
139
140  SDValue ExpandConstantFP(ConstantFPSDNode *CFP, bool UseCP);
141
142  std::pair<SDValue, SDValue> ExpandAtomic(SDNode *Node);
143
144  void ExpandNode(SDNode *Node);
145  void PromoteNode(SDNode *Node);
146
147  void ForgetNode(SDNode *N) {
148    LegalizedNodes.erase(N);
149    if (LegalizePosition == SelectionDAG::allnodes_iterator(N))
150      ++LegalizePosition;
151  }
152
153public:
154  // DAGUpdateListener implementation.
155  virtual void NodeDeleted(SDNode *N, SDNode *E) {
156    ForgetNode(N);
157  }
158  virtual void NodeUpdated(SDNode *N) {}
159
160  // Node replacement helpers
161  void ReplacedNode(SDNode *N) {
162    if (N->use_empty()) {
163      DAG.RemoveDeadNode(N);
164    } else {
165      ForgetNode(N);
166    }
167  }
168  void ReplaceNode(SDNode *Old, SDNode *New) {
169    DAG.ReplaceAllUsesWith(Old, New);
170    ReplacedNode(Old);
171  }
172  void ReplaceNode(SDValue Old, SDValue New) {
173    DAG.ReplaceAllUsesWith(Old, New);
174    ReplacedNode(Old.getNode());
175  }
176  void ReplaceNode(SDNode *Old, const SDValue *New) {
177    DAG.ReplaceAllUsesWith(Old, New);
178    ReplacedNode(Old);
179  }
180};
181}
182
183/// ShuffleWithNarrowerEltType - Return a vector shuffle operation which
184/// performs the same shuffe in terms of order or result bytes, but on a type
185/// whose vector element type is narrower than the original shuffle type.
186/// e.g. <v4i32> <0, 1, 0, 1> -> v8i16 <0, 1, 2, 3, 0, 1, 2, 3>
187SDValue
188SelectionDAGLegalize::ShuffleWithNarrowerEltType(EVT NVT, EVT VT,  SDLoc dl,
189                                                 SDValue N1, SDValue N2,
190                                                 ArrayRef<int> Mask) const {
191  unsigned NumMaskElts = VT.getVectorNumElements();
192  unsigned NumDestElts = NVT.getVectorNumElements();
193  unsigned NumEltsGrowth = NumDestElts / NumMaskElts;
194
195  assert(NumEltsGrowth && "Cannot promote to vector type with fewer elts!");
196
197  if (NumEltsGrowth == 1)
198    return DAG.getVectorShuffle(NVT, dl, N1, N2, &Mask[0]);
199
200  SmallVector<int, 8> NewMask;
201  for (unsigned i = 0; i != NumMaskElts; ++i) {
202    int Idx = Mask[i];
203    for (unsigned j = 0; j != NumEltsGrowth; ++j) {
204      if (Idx < 0)
205        NewMask.push_back(-1);
206      else
207        NewMask.push_back(Idx * NumEltsGrowth + j);
208    }
209  }
210  assert(NewMask.size() == NumDestElts && "Non-integer NumEltsGrowth?");
211  assert(TLI.isShuffleMaskLegal(NewMask, NVT) && "Shuffle not legal?");
212  return DAG.getVectorShuffle(NVT, dl, N1, N2, &NewMask[0]);
213}
214
215SelectionDAGLegalize::SelectionDAGLegalize(SelectionDAG &dag)
216  : SelectionDAG::DAGUpdateListener(dag),
217    TM(dag.getTarget()), TLI(dag.getTargetLoweringInfo()),
218    DAG(dag) {
219}
220
221void SelectionDAGLegalize::LegalizeDAG() {
222  DAG.AssignTopologicalOrder();
223
224  // Visit all the nodes. We start in topological order, so that we see
225  // nodes with their original operands intact. Legalization can produce
226  // new nodes which may themselves need to be legalized. Iterate until all
227  // nodes have been legalized.
228  for (;;) {
229    bool AnyLegalized = false;
230    for (LegalizePosition = DAG.allnodes_end();
231         LegalizePosition != DAG.allnodes_begin(); ) {
232      --LegalizePosition;
233
234      SDNode *N = LegalizePosition;
235      if (LegalizedNodes.insert(N)) {
236        AnyLegalized = true;
237        LegalizeOp(N);
238      }
239    }
240    if (!AnyLegalized)
241      break;
242
243  }
244
245  // Remove dead nodes now.
246  DAG.RemoveDeadNodes();
247}
248
249/// ExpandConstantFP - Expands the ConstantFP node to an integer constant or
250/// a load from the constant pool.
251SDValue
252SelectionDAGLegalize::ExpandConstantFP(ConstantFPSDNode *CFP, bool UseCP) {
253  bool Extend = false;
254  SDLoc dl(CFP);
255
256  // If a FP immediate is precise when represented as a float and if the
257  // target can do an extending load from float to double, we put it into
258  // the constant pool as a float, even if it's is statically typed as a
259  // double.  This shrinks FP constants and canonicalizes them for targets where
260  // an FP extending load is the same cost as a normal load (such as on the x87
261  // fp stack or PPC FP unit).
262  EVT VT = CFP->getValueType(0);
263  ConstantFP *LLVMC = const_cast<ConstantFP*>(CFP->getConstantFPValue());
264  if (!UseCP) {
265    assert((VT == MVT::f64 || VT == MVT::f32) && "Invalid type expansion");
266    return DAG.getConstant(LLVMC->getValueAPF().bitcastToAPInt(),
267                           (VT == MVT::f64) ? MVT::i64 : MVT::i32);
268  }
269
270  EVT OrigVT = VT;
271  EVT SVT = VT;
272  while (SVT != MVT::f32) {
273    SVT = (MVT::SimpleValueType)(SVT.getSimpleVT().SimpleTy - 1);
274    if (ConstantFPSDNode::isValueValidForType(SVT, CFP->getValueAPF()) &&
275        // Only do this if the target has a native EXTLOAD instruction from
276        // smaller type.
277        TLI.isLoadExtLegal(ISD::EXTLOAD, SVT) &&
278        TLI.ShouldShrinkFPConstant(OrigVT)) {
279      Type *SType = SVT.getTypeForEVT(*DAG.getContext());
280      LLVMC = cast<ConstantFP>(ConstantExpr::getFPTrunc(LLVMC, SType));
281      VT = SVT;
282      Extend = true;
283    }
284  }
285
286  SDValue CPIdx = DAG.getConstantPool(LLVMC, TLI.getPointerTy());
287  unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
288  if (Extend) {
289    SDValue Result =
290      DAG.getExtLoad(ISD::EXTLOAD, dl, OrigVT,
291                     DAG.getEntryNode(),
292                     CPIdx, MachinePointerInfo::getConstantPool(),
293                     VT, false, false, Alignment);
294    return Result;
295  }
296  SDValue Result =
297    DAG.getLoad(OrigVT, dl, DAG.getEntryNode(), CPIdx,
298                MachinePointerInfo::getConstantPool(), false, false, false,
299                Alignment);
300  return Result;
301}
302
303/// ExpandUnalignedStore - Expands an unaligned store to 2 half-size stores.
304static void ExpandUnalignedStore(StoreSDNode *ST, SelectionDAG &DAG,
305                                 const TargetLowering &TLI,
306                                 SelectionDAGLegalize *DAGLegalize) {
307  assert(ST->getAddressingMode() == ISD::UNINDEXED &&
308         "unaligned indexed stores not implemented!");
309  SDValue Chain = ST->getChain();
310  SDValue Ptr = ST->getBasePtr();
311  SDValue Val = ST->getValue();
312  EVT VT = Val.getValueType();
313  int Alignment = ST->getAlignment();
314  unsigned AS = ST->getAddressSpace();
315
316  SDLoc dl(ST);
317  if (ST->getMemoryVT().isFloatingPoint() ||
318      ST->getMemoryVT().isVector()) {
319    EVT intVT = EVT::getIntegerVT(*DAG.getContext(), VT.getSizeInBits());
320    if (TLI.isTypeLegal(intVT)) {
321      // Expand to a bitconvert of the value to the integer type of the
322      // same size, then a (misaligned) int store.
323      // FIXME: Does not handle truncating floating point stores!
324      SDValue Result = DAG.getNode(ISD::BITCAST, dl, intVT, Val);
325      Result = DAG.getStore(Chain, dl, Result, Ptr, ST->getPointerInfo(),
326                           ST->isVolatile(), ST->isNonTemporal(), Alignment);
327      DAGLegalize->ReplaceNode(SDValue(ST, 0), Result);
328      return;
329    }
330    // Do a (aligned) store to a stack slot, then copy from the stack slot
331    // to the final destination using (unaligned) integer loads and stores.
332    EVT StoredVT = ST->getMemoryVT();
333    MVT RegVT =
334      TLI.getRegisterType(*DAG.getContext(),
335                          EVT::getIntegerVT(*DAG.getContext(),
336                                            StoredVT.getSizeInBits()));
337    unsigned StoredBytes = StoredVT.getSizeInBits() / 8;
338    unsigned RegBytes = RegVT.getSizeInBits() / 8;
339    unsigned NumRegs = (StoredBytes + RegBytes - 1) / RegBytes;
340
341    // Make sure the stack slot is also aligned for the register type.
342    SDValue StackPtr = DAG.CreateStackTemporary(StoredVT, RegVT);
343
344    // Perform the original store, only redirected to the stack slot.
345    SDValue Store = DAG.getTruncStore(Chain, dl,
346                                      Val, StackPtr, MachinePointerInfo(),
347                                      StoredVT, false, false, 0);
348    SDValue Increment = DAG.getConstant(RegBytes, TLI.getPointerTy(AS));
349    SmallVector<SDValue, 8> Stores;
350    unsigned Offset = 0;
351
352    // Do all but one copies using the full register width.
353    for (unsigned i = 1; i < NumRegs; i++) {
354      // Load one integer register's worth from the stack slot.
355      SDValue Load = DAG.getLoad(RegVT, dl, Store, StackPtr,
356                                 MachinePointerInfo(),
357                                 false, false, false, 0);
358      // Store it to the final location.  Remember the store.
359      Stores.push_back(DAG.getStore(Load.getValue(1), dl, Load, Ptr,
360                                  ST->getPointerInfo().getWithOffset(Offset),
361                                    ST->isVolatile(), ST->isNonTemporal(),
362                                    MinAlign(ST->getAlignment(), Offset)));
363      // Increment the pointers.
364      Offset += RegBytes;
365      StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
366                             Increment);
367      Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr, Increment);
368    }
369
370    // The last store may be partial.  Do a truncating store.  On big-endian
371    // machines this requires an extending load from the stack slot to ensure
372    // that the bits are in the right place.
373    EVT MemVT = EVT::getIntegerVT(*DAG.getContext(),
374                                  8 * (StoredBytes - Offset));
375
376    // Load from the stack slot.
377    SDValue Load = DAG.getExtLoad(ISD::EXTLOAD, dl, RegVT, Store, StackPtr,
378                                  MachinePointerInfo(),
379                                  MemVT, false, false, 0);
380
381    Stores.push_back(DAG.getTruncStore(Load.getValue(1), dl, Load, Ptr,
382                                       ST->getPointerInfo()
383                                         .getWithOffset(Offset),
384                                       MemVT, ST->isVolatile(),
385                                       ST->isNonTemporal(),
386                                       MinAlign(ST->getAlignment(), Offset),
387                                       ST->getTBAAInfo()));
388    // The order of the stores doesn't matter - say it with a TokenFactor.
389    SDValue Result =
390      DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &Stores[0],
391                  Stores.size());
392    DAGLegalize->ReplaceNode(SDValue(ST, 0), Result);
393    return;
394  }
395  assert(ST->getMemoryVT().isInteger() &&
396         !ST->getMemoryVT().isVector() &&
397         "Unaligned store of unknown type.");
398  // Get the half-size VT
399  EVT NewStoredVT = ST->getMemoryVT().getHalfSizedIntegerVT(*DAG.getContext());
400  int NumBits = NewStoredVT.getSizeInBits();
401  int IncrementSize = NumBits / 8;
402
403  // Divide the stored value in two parts.
404  SDValue ShiftAmount = DAG.getConstant(NumBits,
405                                      TLI.getShiftAmountTy(Val.getValueType()));
406  SDValue Lo = Val;
407  SDValue Hi = DAG.getNode(ISD::SRL, dl, VT, Val, ShiftAmount);
408
409  // Store the two parts
410  SDValue Store1, Store2;
411  Store1 = DAG.getTruncStore(Chain, dl, TLI.isLittleEndian()?Lo:Hi, Ptr,
412                             ST->getPointerInfo(), NewStoredVT,
413                             ST->isVolatile(), ST->isNonTemporal(), Alignment);
414
415  Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
416                    DAG.getConstant(IncrementSize, TLI.getPointerTy(AS)));
417  Alignment = MinAlign(Alignment, IncrementSize);
418  Store2 = DAG.getTruncStore(Chain, dl, TLI.isLittleEndian()?Hi:Lo, Ptr,
419                             ST->getPointerInfo().getWithOffset(IncrementSize),
420                             NewStoredVT, ST->isVolatile(), ST->isNonTemporal(),
421                             Alignment, ST->getTBAAInfo());
422
423  SDValue Result =
424    DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Store1, Store2);
425  DAGLegalize->ReplaceNode(SDValue(ST, 0), Result);
426}
427
428/// ExpandUnalignedLoad - Expands an unaligned load to 2 half-size loads.
429static void
430ExpandUnalignedLoad(LoadSDNode *LD, SelectionDAG &DAG,
431                    const TargetLowering &TLI,
432                    SDValue &ValResult, SDValue &ChainResult) {
433  assert(LD->getAddressingMode() == ISD::UNINDEXED &&
434         "unaligned indexed loads not implemented!");
435  SDValue Chain = LD->getChain();
436  SDValue Ptr = LD->getBasePtr();
437  EVT VT = LD->getValueType(0);
438  EVT LoadedVT = LD->getMemoryVT();
439  SDLoc dl(LD);
440  if (VT.isFloatingPoint() || VT.isVector()) {
441    EVT intVT = EVT::getIntegerVT(*DAG.getContext(), LoadedVT.getSizeInBits());
442    if (TLI.isTypeLegal(intVT) && TLI.isTypeLegal(LoadedVT)) {
443      // Expand to a (misaligned) integer load of the same size,
444      // then bitconvert to floating point or vector.
445      SDValue newLoad = DAG.getLoad(intVT, dl, Chain, Ptr,
446                                    LD->getMemOperand());
447      SDValue Result = DAG.getNode(ISD::BITCAST, dl, LoadedVT, newLoad);
448      if (LoadedVT != VT)
449        Result = DAG.getNode(VT.isFloatingPoint() ? ISD::FP_EXTEND :
450                             ISD::ANY_EXTEND, dl, VT, Result);
451
452      ValResult = Result;
453      ChainResult = Chain;
454      return;
455    }
456
457    // Copy the value to a (aligned) stack slot using (unaligned) integer
458    // loads and stores, then do a (aligned) load from the stack slot.
459    MVT RegVT = TLI.getRegisterType(*DAG.getContext(), intVT);
460    unsigned LoadedBytes = LoadedVT.getSizeInBits() / 8;
461    unsigned RegBytes = RegVT.getSizeInBits() / 8;
462    unsigned NumRegs = (LoadedBytes + RegBytes - 1) / RegBytes;
463
464    // Make sure the stack slot is also aligned for the register type.
465    SDValue StackBase = DAG.CreateStackTemporary(LoadedVT, RegVT);
466
467    SDValue Increment = DAG.getConstant(RegBytes, TLI.getPointerTy());
468    SmallVector<SDValue, 8> Stores;
469    SDValue StackPtr = StackBase;
470    unsigned Offset = 0;
471
472    // Do all but one copies using the full register width.
473    for (unsigned i = 1; i < NumRegs; i++) {
474      // Load one integer register's worth from the original location.
475      SDValue Load = DAG.getLoad(RegVT, dl, Chain, Ptr,
476                                 LD->getPointerInfo().getWithOffset(Offset),
477                                 LD->isVolatile(), LD->isNonTemporal(),
478                                 LD->isInvariant(),
479                                 MinAlign(LD->getAlignment(), Offset),
480                                 LD->getTBAAInfo());
481      // Follow the load with a store to the stack slot.  Remember the store.
482      Stores.push_back(DAG.getStore(Load.getValue(1), dl, Load, StackPtr,
483                                    MachinePointerInfo(), false, false, 0));
484      // Increment the pointers.
485      Offset += RegBytes;
486      Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr, Increment);
487      StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
488                             Increment);
489    }
490
491    // The last copy may be partial.  Do an extending load.
492    EVT MemVT = EVT::getIntegerVT(*DAG.getContext(),
493                                  8 * (LoadedBytes - Offset));
494    SDValue Load = DAG.getExtLoad(ISD::EXTLOAD, dl, RegVT, Chain, Ptr,
495                                  LD->getPointerInfo().getWithOffset(Offset),
496                                  MemVT, LD->isVolatile(),
497                                  LD->isNonTemporal(),
498                                  MinAlign(LD->getAlignment(), Offset),
499                                  LD->getTBAAInfo());
500    // Follow the load with a store to the stack slot.  Remember the store.
501    // On big-endian machines this requires a truncating store to ensure
502    // that the bits end up in the right place.
503    Stores.push_back(DAG.getTruncStore(Load.getValue(1), dl, Load, StackPtr,
504                                       MachinePointerInfo(), MemVT,
505                                       false, false, 0));
506
507    // The order of the stores doesn't matter - say it with a TokenFactor.
508    SDValue TF = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &Stores[0],
509                             Stores.size());
510
511    // Finally, perform the original load only redirected to the stack slot.
512    Load = DAG.getExtLoad(LD->getExtensionType(), dl, VT, TF, StackBase,
513                          MachinePointerInfo(), LoadedVT, false, false, 0);
514
515    // Callers expect a MERGE_VALUES node.
516    ValResult = Load;
517    ChainResult = TF;
518    return;
519  }
520  assert(LoadedVT.isInteger() && !LoadedVT.isVector() &&
521         "Unaligned load of unsupported type.");
522
523  // Compute the new VT that is half the size of the old one.  This is an
524  // integer MVT.
525  unsigned NumBits = LoadedVT.getSizeInBits();
526  EVT NewLoadedVT;
527  NewLoadedVT = EVT::getIntegerVT(*DAG.getContext(), NumBits/2);
528  NumBits >>= 1;
529
530  unsigned Alignment = LD->getAlignment();
531  unsigned IncrementSize = NumBits / 8;
532  ISD::LoadExtType HiExtType = LD->getExtensionType();
533
534  // If the original load is NON_EXTLOAD, the hi part load must be ZEXTLOAD.
535  if (HiExtType == ISD::NON_EXTLOAD)
536    HiExtType = ISD::ZEXTLOAD;
537
538  // Load the value in two parts
539  SDValue Lo, Hi;
540  if (TLI.isLittleEndian()) {
541    Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, VT, Chain, Ptr, LD->getPointerInfo(),
542                        NewLoadedVT, LD->isVolatile(),
543                        LD->isNonTemporal(), Alignment, LD->getTBAAInfo());
544    Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
545                      DAG.getConstant(IncrementSize, Ptr.getValueType()));
546    Hi = DAG.getExtLoad(HiExtType, dl, VT, Chain, Ptr,
547                        LD->getPointerInfo().getWithOffset(IncrementSize),
548                        NewLoadedVT, LD->isVolatile(),
549                        LD->isNonTemporal(), MinAlign(Alignment, IncrementSize),
550                        LD->getTBAAInfo());
551  } else {
552    Hi = DAG.getExtLoad(HiExtType, dl, VT, Chain, Ptr, LD->getPointerInfo(),
553                        NewLoadedVT, LD->isVolatile(),
554                        LD->isNonTemporal(), Alignment, LD->getTBAAInfo());
555    Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
556                      DAG.getConstant(IncrementSize, Ptr.getValueType()));
557    Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, VT, Chain, Ptr,
558                        LD->getPointerInfo().getWithOffset(IncrementSize),
559                        NewLoadedVT, LD->isVolatile(),
560                        LD->isNonTemporal(), MinAlign(Alignment, IncrementSize),
561                        LD->getTBAAInfo());
562  }
563
564  // aggregate the two parts
565  SDValue ShiftAmount = DAG.getConstant(NumBits,
566                                       TLI.getShiftAmountTy(Hi.getValueType()));
567  SDValue Result = DAG.getNode(ISD::SHL, dl, VT, Hi, ShiftAmount);
568  Result = DAG.getNode(ISD::OR, dl, VT, Result, Lo);
569
570  SDValue TF = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
571                             Hi.getValue(1));
572
573  ValResult = Result;
574  ChainResult = TF;
575}
576
577/// PerformInsertVectorEltInMemory - Some target cannot handle a variable
578/// insertion index for the INSERT_VECTOR_ELT instruction.  In this case, it
579/// is necessary to spill the vector being inserted into to memory, perform
580/// the insert there, and then read the result back.
581SDValue SelectionDAGLegalize::
582PerformInsertVectorEltInMemory(SDValue Vec, SDValue Val, SDValue Idx,
583                               SDLoc dl) {
584  SDValue Tmp1 = Vec;
585  SDValue Tmp2 = Val;
586  SDValue Tmp3 = Idx;
587
588  // If the target doesn't support this, we have to spill the input vector
589  // to a temporary stack slot, update the element, then reload it.  This is
590  // badness.  We could also load the value into a vector register (either
591  // with a "move to register" or "extload into register" instruction, then
592  // permute it into place, if the idx is a constant and if the idx is
593  // supported by the target.
594  EVT VT    = Tmp1.getValueType();
595  EVT EltVT = VT.getVectorElementType();
596  EVT IdxVT = Tmp3.getValueType();
597  EVT PtrVT = TLI.getPointerTy();
598  SDValue StackPtr = DAG.CreateStackTemporary(VT);
599
600  int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
601
602  // Store the vector.
603  SDValue Ch = DAG.getStore(DAG.getEntryNode(), dl, Tmp1, StackPtr,
604                            MachinePointerInfo::getFixedStack(SPFI),
605                            false, false, 0);
606
607  // Truncate or zero extend offset to target pointer type.
608  unsigned CastOpc = IdxVT.bitsGT(PtrVT) ? ISD::TRUNCATE : ISD::ZERO_EXTEND;
609  Tmp3 = DAG.getNode(CastOpc, dl, PtrVT, Tmp3);
610  // Add the offset to the index.
611  unsigned EltSize = EltVT.getSizeInBits()/8;
612  Tmp3 = DAG.getNode(ISD::MUL, dl, IdxVT, Tmp3,DAG.getConstant(EltSize, IdxVT));
613  SDValue StackPtr2 = DAG.getNode(ISD::ADD, dl, IdxVT, Tmp3, StackPtr);
614  // Store the scalar value.
615  Ch = DAG.getTruncStore(Ch, dl, Tmp2, StackPtr2, MachinePointerInfo(), EltVT,
616                         false, false, 0);
617  // Load the updated vector.
618  return DAG.getLoad(VT, dl, Ch, StackPtr,
619                     MachinePointerInfo::getFixedStack(SPFI), false, false,
620                     false, 0);
621}
622
623
624SDValue SelectionDAGLegalize::
625ExpandINSERT_VECTOR_ELT(SDValue Vec, SDValue Val, SDValue Idx, SDLoc dl) {
626  if (ConstantSDNode *InsertPos = dyn_cast<ConstantSDNode>(Idx)) {
627    // SCALAR_TO_VECTOR requires that the type of the value being inserted
628    // match the element type of the vector being created, except for
629    // integers in which case the inserted value can be over width.
630    EVT EltVT = Vec.getValueType().getVectorElementType();
631    if (Val.getValueType() == EltVT ||
632        (EltVT.isInteger() && Val.getValueType().bitsGE(EltVT))) {
633      SDValue ScVec = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl,
634                                  Vec.getValueType(), Val);
635
636      unsigned NumElts = Vec.getValueType().getVectorNumElements();
637      // We generate a shuffle of InVec and ScVec, so the shuffle mask
638      // should be 0,1,2,3,4,5... with the appropriate element replaced with
639      // elt 0 of the RHS.
640      SmallVector<int, 8> ShufOps;
641      for (unsigned i = 0; i != NumElts; ++i)
642        ShufOps.push_back(i != InsertPos->getZExtValue() ? i : NumElts);
643
644      return DAG.getVectorShuffle(Vec.getValueType(), dl, Vec, ScVec,
645                                  &ShufOps[0]);
646    }
647  }
648  return PerformInsertVectorEltInMemory(Vec, Val, Idx, dl);
649}
650
651SDValue SelectionDAGLegalize::OptimizeFloatStore(StoreSDNode* ST) {
652  // Turn 'store float 1.0, Ptr' -> 'store int 0x12345678, Ptr'
653  // FIXME: We shouldn't do this for TargetConstantFP's.
654  // FIXME: move this to the DAG Combiner!  Note that we can't regress due
655  // to phase ordering between legalized code and the dag combiner.  This
656  // probably means that we need to integrate dag combiner and legalizer
657  // together.
658  // We generally can't do this one for long doubles.
659  SDValue Chain = ST->getChain();
660  SDValue Ptr = ST->getBasePtr();
661  unsigned Alignment = ST->getAlignment();
662  bool isVolatile = ST->isVolatile();
663  bool isNonTemporal = ST->isNonTemporal();
664  const MDNode *TBAAInfo = ST->getTBAAInfo();
665  SDLoc dl(ST);
666  if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(ST->getValue())) {
667    if (CFP->getValueType(0) == MVT::f32 &&
668        TLI.isTypeLegal(MVT::i32)) {
669      SDValue Con = DAG.getConstant(CFP->getValueAPF().
670                                      bitcastToAPInt().zextOrTrunc(32),
671                              MVT::i32);
672      return DAG.getStore(Chain, dl, Con, Ptr, ST->getPointerInfo(),
673                          isVolatile, isNonTemporal, Alignment, TBAAInfo);
674    }
675
676    if (CFP->getValueType(0) == MVT::f64) {
677      // If this target supports 64-bit registers, do a single 64-bit store.
678      if (TLI.isTypeLegal(MVT::i64)) {
679        SDValue Con = DAG.getConstant(CFP->getValueAPF().bitcastToAPInt().
680                                  zextOrTrunc(64), MVT::i64);
681        return DAG.getStore(Chain, dl, Con, Ptr, ST->getPointerInfo(),
682                            isVolatile, isNonTemporal, Alignment, TBAAInfo);
683      }
684
685      if (TLI.isTypeLegal(MVT::i32) && !ST->isVolatile()) {
686        // Otherwise, if the target supports 32-bit registers, use 2 32-bit
687        // stores.  If the target supports neither 32- nor 64-bits, this
688        // xform is certainly not worth it.
689        const APInt &IntVal =CFP->getValueAPF().bitcastToAPInt();
690        SDValue Lo = DAG.getConstant(IntVal.trunc(32), MVT::i32);
691        SDValue Hi = DAG.getConstant(IntVal.lshr(32).trunc(32), MVT::i32);
692        if (TLI.isBigEndian()) std::swap(Lo, Hi);
693
694        Lo = DAG.getStore(Chain, dl, Lo, Ptr, ST->getPointerInfo(), isVolatile,
695                          isNonTemporal, Alignment, TBAAInfo);
696        Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
697                          DAG.getConstant(4, Ptr.getValueType()));
698        Hi = DAG.getStore(Chain, dl, Hi, Ptr,
699                          ST->getPointerInfo().getWithOffset(4),
700                          isVolatile, isNonTemporal, MinAlign(Alignment, 4U),
701                          TBAAInfo);
702
703        return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
704      }
705    }
706  }
707  return SDValue(0, 0);
708}
709
710void SelectionDAGLegalize::LegalizeStoreOps(SDNode *Node) {
711    StoreSDNode *ST = cast<StoreSDNode>(Node);
712    SDValue Chain = ST->getChain();
713    SDValue Ptr = ST->getBasePtr();
714    SDLoc dl(Node);
715
716    unsigned Alignment = ST->getAlignment();
717    bool isVolatile = ST->isVolatile();
718    bool isNonTemporal = ST->isNonTemporal();
719    const MDNode *TBAAInfo = ST->getTBAAInfo();
720
721    if (!ST->isTruncatingStore()) {
722      if (SDNode *OptStore = OptimizeFloatStore(ST).getNode()) {
723        ReplaceNode(ST, OptStore);
724        return;
725      }
726
727      {
728        SDValue Value = ST->getValue();
729        MVT VT = Value.getSimpleValueType();
730        switch (TLI.getOperationAction(ISD::STORE, VT)) {
731        default: llvm_unreachable("This action is not supported yet!");
732        case TargetLowering::Legal:
733          // If this is an unaligned store and the target doesn't support it,
734          // expand it.
735          if (!TLI.allowsUnalignedMemoryAccesses(ST->getMemoryVT())) {
736            Type *Ty = ST->getMemoryVT().getTypeForEVT(*DAG.getContext());
737            unsigned ABIAlignment= TLI.getDataLayout()->getABITypeAlignment(Ty);
738            if (ST->getAlignment() < ABIAlignment)
739              ExpandUnalignedStore(cast<StoreSDNode>(Node),
740                                   DAG, TLI, this);
741          }
742          break;
743        case TargetLowering::Custom: {
744          SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG);
745          if (Res.getNode())
746            ReplaceNode(SDValue(Node, 0), Res);
747          return;
748        }
749        case TargetLowering::Promote: {
750          MVT NVT = TLI.getTypeToPromoteTo(ISD::STORE, VT);
751          assert(NVT.getSizeInBits() == VT.getSizeInBits() &&
752                 "Can only promote stores to same size type");
753          Value = DAG.getNode(ISD::BITCAST, dl, NVT, Value);
754          SDValue Result =
755            DAG.getStore(Chain, dl, Value, Ptr,
756                         ST->getPointerInfo(), isVolatile,
757                         isNonTemporal, Alignment, TBAAInfo);
758          ReplaceNode(SDValue(Node, 0), Result);
759          break;
760        }
761        }
762        return;
763      }
764    } else {
765      SDValue Value = ST->getValue();
766
767      EVT StVT = ST->getMemoryVT();
768      unsigned StWidth = StVT.getSizeInBits();
769
770      if (StWidth != StVT.getStoreSizeInBits()) {
771        // Promote to a byte-sized store with upper bits zero if not
772        // storing an integral number of bytes.  For example, promote
773        // TRUNCSTORE:i1 X -> TRUNCSTORE:i8 (and X, 1)
774        EVT NVT = EVT::getIntegerVT(*DAG.getContext(),
775                                    StVT.getStoreSizeInBits());
776        Value = DAG.getZeroExtendInReg(Value, dl, StVT);
777        SDValue Result =
778          DAG.getTruncStore(Chain, dl, Value, Ptr, ST->getPointerInfo(),
779                            NVT, isVolatile, isNonTemporal, Alignment,
780                            TBAAInfo);
781        ReplaceNode(SDValue(Node, 0), Result);
782      } else if (StWidth & (StWidth - 1)) {
783        // If not storing a power-of-2 number of bits, expand as two stores.
784        assert(!StVT.isVector() && "Unsupported truncstore!");
785        unsigned RoundWidth = 1 << Log2_32(StWidth);
786        assert(RoundWidth < StWidth);
787        unsigned ExtraWidth = StWidth - RoundWidth;
788        assert(ExtraWidth < RoundWidth);
789        assert(!(RoundWidth % 8) && !(ExtraWidth % 8) &&
790               "Store size not an integral number of bytes!");
791        EVT RoundVT = EVT::getIntegerVT(*DAG.getContext(), RoundWidth);
792        EVT ExtraVT = EVT::getIntegerVT(*DAG.getContext(), ExtraWidth);
793        SDValue Lo, Hi;
794        unsigned IncrementSize;
795
796        if (TLI.isLittleEndian()) {
797          // TRUNCSTORE:i24 X -> TRUNCSTORE:i16 X, TRUNCSTORE@+2:i8 (srl X, 16)
798          // Store the bottom RoundWidth bits.
799          Lo = DAG.getTruncStore(Chain, dl, Value, Ptr, ST->getPointerInfo(),
800                                 RoundVT,
801                                 isVolatile, isNonTemporal, Alignment,
802                                 TBAAInfo);
803
804          // Store the remaining ExtraWidth bits.
805          IncrementSize = RoundWidth / 8;
806          Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
807                            DAG.getConstant(IncrementSize, Ptr.getValueType()));
808          Hi = DAG.getNode(ISD::SRL, dl, Value.getValueType(), Value,
809                           DAG.getConstant(RoundWidth,
810                                    TLI.getShiftAmountTy(Value.getValueType())));
811          Hi = DAG.getTruncStore(Chain, dl, Hi, Ptr,
812                             ST->getPointerInfo().getWithOffset(IncrementSize),
813                                 ExtraVT, isVolatile, isNonTemporal,
814                                 MinAlign(Alignment, IncrementSize), TBAAInfo);
815        } else {
816          // Big endian - avoid unaligned stores.
817          // TRUNCSTORE:i24 X -> TRUNCSTORE:i16 (srl X, 8), TRUNCSTORE@+2:i8 X
818          // Store the top RoundWidth bits.
819          Hi = DAG.getNode(ISD::SRL, dl, Value.getValueType(), Value,
820                           DAG.getConstant(ExtraWidth,
821                                    TLI.getShiftAmountTy(Value.getValueType())));
822          Hi = DAG.getTruncStore(Chain, dl, Hi, Ptr, ST->getPointerInfo(),
823                                 RoundVT, isVolatile, isNonTemporal, Alignment,
824                                 TBAAInfo);
825
826          // Store the remaining ExtraWidth bits.
827          IncrementSize = RoundWidth / 8;
828          Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
829                             DAG.getConstant(IncrementSize, Ptr.getValueType()));
830          Lo = DAG.getTruncStore(Chain, dl, Value, Ptr,
831                              ST->getPointerInfo().getWithOffset(IncrementSize),
832                                 ExtraVT, isVolatile, isNonTemporal,
833                                 MinAlign(Alignment, IncrementSize), TBAAInfo);
834        }
835
836        // The order of the stores doesn't matter.
837        SDValue Result = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
838        ReplaceNode(SDValue(Node, 0), Result);
839      } else {
840        switch (TLI.getTruncStoreAction(ST->getValue().getSimpleValueType(),
841                                        StVT.getSimpleVT())) {
842        default: llvm_unreachable("This action is not supported yet!");
843        case TargetLowering::Legal:
844          // If this is an unaligned store and the target doesn't support it,
845          // expand it.
846          if (!TLI.allowsUnalignedMemoryAccesses(ST->getMemoryVT())) {
847            Type *Ty = ST->getMemoryVT().getTypeForEVT(*DAG.getContext());
848            unsigned ABIAlignment= TLI.getDataLayout()->getABITypeAlignment(Ty);
849            if (ST->getAlignment() < ABIAlignment)
850              ExpandUnalignedStore(cast<StoreSDNode>(Node), DAG, TLI, this);
851          }
852          break;
853        case TargetLowering::Custom: {
854          SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG);
855          if (Res.getNode())
856            ReplaceNode(SDValue(Node, 0), Res);
857          return;
858        }
859        case TargetLowering::Expand:
860          assert(!StVT.isVector() &&
861                 "Vector Stores are handled in LegalizeVectorOps");
862
863          // TRUNCSTORE:i16 i32 -> STORE i16
864          assert(TLI.isTypeLegal(StVT) &&
865                 "Do not know how to expand this store!");
866          Value = DAG.getNode(ISD::TRUNCATE, dl, StVT, Value);
867          SDValue Result =
868            DAG.getStore(Chain, dl, Value, Ptr, ST->getPointerInfo(),
869                         isVolatile, isNonTemporal, Alignment, TBAAInfo);
870          ReplaceNode(SDValue(Node, 0), Result);
871          break;
872        }
873      }
874    }
875}
876
877void SelectionDAGLegalize::LegalizeLoadOps(SDNode *Node) {
878  LoadSDNode *LD = cast<LoadSDNode>(Node);
879  SDValue Chain = LD->getChain();  // The chain.
880  SDValue Ptr = LD->getBasePtr();  // The base pointer.
881  SDValue Value;                   // The value returned by the load op.
882  SDLoc dl(Node);
883
884  ISD::LoadExtType ExtType = LD->getExtensionType();
885  if (ExtType == ISD::NON_EXTLOAD) {
886    MVT VT = Node->getSimpleValueType(0);
887    SDValue RVal = SDValue(Node, 0);
888    SDValue RChain = SDValue(Node, 1);
889
890    switch (TLI.getOperationAction(Node->getOpcode(), VT)) {
891    default: llvm_unreachable("This action is not supported yet!");
892    case TargetLowering::Legal:
893      // If this is an unaligned load and the target doesn't support it,
894      // expand it.
895      if (!TLI.allowsUnalignedMemoryAccesses(LD->getMemoryVT())) {
896        Type *Ty = LD->getMemoryVT().getTypeForEVT(*DAG.getContext());
897        unsigned ABIAlignment =
898          TLI.getDataLayout()->getABITypeAlignment(Ty);
899        if (LD->getAlignment() < ABIAlignment){
900          ExpandUnalignedLoad(cast<LoadSDNode>(Node), DAG, TLI, RVal, RChain);
901        }
902      }
903      break;
904    case TargetLowering::Custom: {
905      SDValue Res = TLI.LowerOperation(RVal, DAG);
906      if (Res.getNode()) {
907        RVal = Res;
908        RChain = Res.getValue(1);
909      }
910      break;
911    }
912    case TargetLowering::Promote: {
913      MVT NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), VT);
914      assert(NVT.getSizeInBits() == VT.getSizeInBits() &&
915             "Can only promote loads to same size type");
916
917      SDValue Res = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getMemOperand());
918      RVal = DAG.getNode(ISD::BITCAST, dl, VT, Res);
919      RChain = Res.getValue(1);
920      break;
921    }
922    }
923    if (RChain.getNode() != Node) {
924      assert(RVal.getNode() != Node && "Load must be completely replaced");
925      DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 0), RVal);
926      DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 1), RChain);
927      ReplacedNode(Node);
928    }
929    return;
930  }
931
932  EVT SrcVT = LD->getMemoryVT();
933  unsigned SrcWidth = SrcVT.getSizeInBits();
934  unsigned Alignment = LD->getAlignment();
935  bool isVolatile = LD->isVolatile();
936  bool isNonTemporal = LD->isNonTemporal();
937  const MDNode *TBAAInfo = LD->getTBAAInfo();
938
939  if (SrcWidth != SrcVT.getStoreSizeInBits() &&
940      // Some targets pretend to have an i1 loading operation, and actually
941      // load an i8.  This trick is correct for ZEXTLOAD because the top 7
942      // bits are guaranteed to be zero; it helps the optimizers understand
943      // that these bits are zero.  It is also useful for EXTLOAD, since it
944      // tells the optimizers that those bits are undefined.  It would be
945      // nice to have an effective generic way of getting these benefits...
946      // Until such a way is found, don't insist on promoting i1 here.
947      (SrcVT != MVT::i1 ||
948       TLI.getLoadExtAction(ExtType, MVT::i1) == TargetLowering::Promote)) {
949    // Promote to a byte-sized load if not loading an integral number of
950    // bytes.  For example, promote EXTLOAD:i20 -> EXTLOAD:i24.
951    unsigned NewWidth = SrcVT.getStoreSizeInBits();
952    EVT NVT = EVT::getIntegerVT(*DAG.getContext(), NewWidth);
953    SDValue Ch;
954
955    // The extra bits are guaranteed to be zero, since we stored them that
956    // way.  A zext load from NVT thus automatically gives zext from SrcVT.
957
958    ISD::LoadExtType NewExtType =
959      ExtType == ISD::ZEXTLOAD ? ISD::ZEXTLOAD : ISD::EXTLOAD;
960
961    SDValue Result =
962      DAG.getExtLoad(NewExtType, dl, Node->getValueType(0),
963                     Chain, Ptr, LD->getPointerInfo(),
964                     NVT, isVolatile, isNonTemporal, Alignment, TBAAInfo);
965
966    Ch = Result.getValue(1); // The chain.
967
968    if (ExtType == ISD::SEXTLOAD)
969      // Having the top bits zero doesn't help when sign extending.
970      Result = DAG.getNode(ISD::SIGN_EXTEND_INREG, dl,
971                           Result.getValueType(),
972                           Result, DAG.getValueType(SrcVT));
973    else if (ExtType == ISD::ZEXTLOAD || NVT == Result.getValueType())
974      // All the top bits are guaranteed to be zero - inform the optimizers.
975      Result = DAG.getNode(ISD::AssertZext, dl,
976                           Result.getValueType(), Result,
977                           DAG.getValueType(SrcVT));
978
979    Value = Result;
980    Chain = Ch;
981  } else if (SrcWidth & (SrcWidth - 1)) {
982    // If not loading a power-of-2 number of bits, expand as two loads.
983    assert(!SrcVT.isVector() && "Unsupported extload!");
984    unsigned RoundWidth = 1 << Log2_32(SrcWidth);
985    assert(RoundWidth < SrcWidth);
986    unsigned ExtraWidth = SrcWidth - RoundWidth;
987    assert(ExtraWidth < RoundWidth);
988    assert(!(RoundWidth % 8) && !(ExtraWidth % 8) &&
989           "Load size not an integral number of bytes!");
990    EVT RoundVT = EVT::getIntegerVT(*DAG.getContext(), RoundWidth);
991    EVT ExtraVT = EVT::getIntegerVT(*DAG.getContext(), ExtraWidth);
992    SDValue Lo, Hi, Ch;
993    unsigned IncrementSize;
994
995    if (TLI.isLittleEndian()) {
996      // EXTLOAD:i24 -> ZEXTLOAD:i16 | (shl EXTLOAD@+2:i8, 16)
997      // Load the bottom RoundWidth bits.
998      Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, Node->getValueType(0),
999                          Chain, Ptr,
1000                          LD->getPointerInfo(), RoundVT, isVolatile,
1001                          isNonTemporal, Alignment, TBAAInfo);
1002
1003      // Load the remaining ExtraWidth bits.
1004      IncrementSize = RoundWidth / 8;
1005      Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
1006                         DAG.getConstant(IncrementSize, Ptr.getValueType()));
1007      Hi = DAG.getExtLoad(ExtType, dl, Node->getValueType(0), Chain, Ptr,
1008                          LD->getPointerInfo().getWithOffset(IncrementSize),
1009                          ExtraVT, isVolatile, isNonTemporal,
1010                          MinAlign(Alignment, IncrementSize), TBAAInfo);
1011
1012      // Build a factor node to remember that this load is independent of
1013      // the other one.
1014      Ch = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
1015                       Hi.getValue(1));
1016
1017      // Move the top bits to the right place.
1018      Hi = DAG.getNode(ISD::SHL, dl, Hi.getValueType(), Hi,
1019                       DAG.getConstant(RoundWidth,
1020                                       TLI.getShiftAmountTy(Hi.getValueType())));
1021
1022      // Join the hi and lo parts.
1023      Value = DAG.getNode(ISD::OR, dl, Node->getValueType(0), Lo, Hi);
1024    } else {
1025      // Big endian - avoid unaligned loads.
1026      // EXTLOAD:i24 -> (shl EXTLOAD:i16, 8) | ZEXTLOAD@+2:i8
1027      // Load the top RoundWidth bits.
1028      Hi = DAG.getExtLoad(ExtType, dl, Node->getValueType(0), Chain, Ptr,
1029                          LD->getPointerInfo(), RoundVT, isVolatile,
1030                          isNonTemporal, Alignment, TBAAInfo);
1031
1032      // Load the remaining ExtraWidth bits.
1033      IncrementSize = RoundWidth / 8;
1034      Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
1035                         DAG.getConstant(IncrementSize, Ptr.getValueType()));
1036      Lo = DAG.getExtLoad(ISD::ZEXTLOAD,
1037                          dl, Node->getValueType(0), Chain, Ptr,
1038                          LD->getPointerInfo().getWithOffset(IncrementSize),
1039                          ExtraVT, isVolatile, isNonTemporal,
1040                          MinAlign(Alignment, IncrementSize), TBAAInfo);
1041
1042      // Build a factor node to remember that this load is independent of
1043      // the other one.
1044      Ch = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
1045                       Hi.getValue(1));
1046
1047      // Move the top bits to the right place.
1048      Hi = DAG.getNode(ISD::SHL, dl, Hi.getValueType(), Hi,
1049                       DAG.getConstant(ExtraWidth,
1050                                       TLI.getShiftAmountTy(Hi.getValueType())));
1051
1052      // Join the hi and lo parts.
1053      Value = DAG.getNode(ISD::OR, dl, Node->getValueType(0), Lo, Hi);
1054    }
1055
1056    Chain = Ch;
1057  } else {
1058    bool isCustom = false;
1059    switch (TLI.getLoadExtAction(ExtType, SrcVT.getSimpleVT())) {
1060    default: llvm_unreachable("This action is not supported yet!");
1061    case TargetLowering::Custom:
1062             isCustom = true;
1063             // FALLTHROUGH
1064    case TargetLowering::Legal: {
1065             Value = SDValue(Node, 0);
1066             Chain = SDValue(Node, 1);
1067
1068             if (isCustom) {
1069               SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG);
1070               if (Res.getNode()) {
1071                 Value = Res;
1072                 Chain = Res.getValue(1);
1073               }
1074             } else {
1075               // If this is an unaligned load and the target doesn't support it,
1076               // expand it.
1077               if (!TLI.allowsUnalignedMemoryAccesses(LD->getMemoryVT())) {
1078                 Type *Ty =
1079                   LD->getMemoryVT().getTypeForEVT(*DAG.getContext());
1080                 unsigned ABIAlignment =
1081                   TLI.getDataLayout()->getABITypeAlignment(Ty);
1082                 if (LD->getAlignment() < ABIAlignment){
1083                   ExpandUnalignedLoad(cast<LoadSDNode>(Node),
1084                                       DAG, TLI, Value, Chain);
1085                 }
1086               }
1087             }
1088             break;
1089    }
1090    case TargetLowering::Expand:
1091             if (!TLI.isLoadExtLegal(ISD::EXTLOAD, SrcVT) && TLI.isTypeLegal(SrcVT)) {
1092               SDValue Load = DAG.getLoad(SrcVT, dl, Chain, Ptr,
1093                                          LD->getMemOperand());
1094               unsigned ExtendOp;
1095               switch (ExtType) {
1096               case ISD::EXTLOAD:
1097                 ExtendOp = (SrcVT.isFloatingPoint() ?
1098                             ISD::FP_EXTEND : ISD::ANY_EXTEND);
1099                 break;
1100               case ISD::SEXTLOAD: ExtendOp = ISD::SIGN_EXTEND; break;
1101               case ISD::ZEXTLOAD: ExtendOp = ISD::ZERO_EXTEND; break;
1102               default: llvm_unreachable("Unexpected extend load type!");
1103               }
1104               Value = DAG.getNode(ExtendOp, dl, Node->getValueType(0), Load);
1105               Chain = Load.getValue(1);
1106               break;
1107             }
1108
1109             assert(!SrcVT.isVector() &&
1110                    "Vector Loads are handled in LegalizeVectorOps");
1111
1112             // FIXME: This does not work for vectors on most targets.  Sign- and
1113             // zero-extend operations are currently folded into extending loads,
1114             // whether they are legal or not, and then we end up here without any
1115             // support for legalizing them.
1116             assert(ExtType != ISD::EXTLOAD &&
1117                    "EXTLOAD should always be supported!");
1118             // Turn the unsupported load into an EXTLOAD followed by an explicit
1119             // zero/sign extend inreg.
1120             SDValue Result = DAG.getExtLoad(ISD::EXTLOAD, dl, Node->getValueType(0),
1121                                             Chain, Ptr, SrcVT,
1122                                             LD->getMemOperand());
1123             SDValue ValRes;
1124             if (ExtType == ISD::SEXTLOAD)
1125               ValRes = DAG.getNode(ISD::SIGN_EXTEND_INREG, dl,
1126                                    Result.getValueType(),
1127                                    Result, DAG.getValueType(SrcVT));
1128             else
1129               ValRes = DAG.getZeroExtendInReg(Result, dl, SrcVT.getScalarType());
1130             Value = ValRes;
1131             Chain = Result.getValue(1);
1132             break;
1133    }
1134  }
1135
1136  // Since loads produce two values, make sure to remember that we legalized
1137  // both of them.
1138  if (Chain.getNode() != Node) {
1139    assert(Value.getNode() != Node && "Load must be completely replaced");
1140    DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 0), Value);
1141    DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 1), Chain);
1142    ReplacedNode(Node);
1143  }
1144}
1145
1146/// LegalizeOp - Return a legal replacement for the given operation, with
1147/// all legal operands.
1148void SelectionDAGLegalize::LegalizeOp(SDNode *Node) {
1149  if (Node->getOpcode() == ISD::TargetConstant) // Allow illegal target nodes.
1150    return;
1151
1152  for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
1153    assert(TLI.getTypeAction(*DAG.getContext(), Node->getValueType(i)) ==
1154             TargetLowering::TypeLegal &&
1155           "Unexpected illegal type!");
1156
1157  for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i)
1158    assert((TLI.getTypeAction(*DAG.getContext(),
1159                              Node->getOperand(i).getValueType()) ==
1160              TargetLowering::TypeLegal ||
1161            Node->getOperand(i).getOpcode() == ISD::TargetConstant) &&
1162           "Unexpected illegal type!");
1163
1164  // Figure out the correct action; the way to query this varies by opcode
1165  TargetLowering::LegalizeAction Action = TargetLowering::Legal;
1166  bool SimpleFinishLegalizing = true;
1167  switch (Node->getOpcode()) {
1168  case ISD::INTRINSIC_W_CHAIN:
1169  case ISD::INTRINSIC_WO_CHAIN:
1170  case ISD::INTRINSIC_VOID:
1171  case ISD::STACKSAVE:
1172    Action = TLI.getOperationAction(Node->getOpcode(), MVT::Other);
1173    break;
1174  case ISD::VAARG:
1175    Action = TLI.getOperationAction(Node->getOpcode(),
1176                                    Node->getValueType(0));
1177    if (Action != TargetLowering::Promote)
1178      Action = TLI.getOperationAction(Node->getOpcode(), MVT::Other);
1179    break;
1180  case ISD::SINT_TO_FP:
1181  case ISD::UINT_TO_FP:
1182  case ISD::EXTRACT_VECTOR_ELT:
1183    Action = TLI.getOperationAction(Node->getOpcode(),
1184                                    Node->getOperand(0).getValueType());
1185    break;
1186  case ISD::FP_ROUND_INREG:
1187  case ISD::SIGN_EXTEND_INREG: {
1188    EVT InnerType = cast<VTSDNode>(Node->getOperand(1))->getVT();
1189    Action = TLI.getOperationAction(Node->getOpcode(), InnerType);
1190    break;
1191  }
1192  case ISD::ATOMIC_STORE: {
1193    Action = TLI.getOperationAction(Node->getOpcode(),
1194                                    Node->getOperand(2).getValueType());
1195    break;
1196  }
1197  case ISD::SELECT_CC:
1198  case ISD::SETCC:
1199  case ISD::BR_CC: {
1200    unsigned CCOperand = Node->getOpcode() == ISD::SELECT_CC ? 4 :
1201                         Node->getOpcode() == ISD::SETCC ? 2 : 1;
1202    unsigned CompareOperand = Node->getOpcode() == ISD::BR_CC ? 2 : 0;
1203    MVT OpVT = Node->getOperand(CompareOperand).getSimpleValueType();
1204    ISD::CondCode CCCode =
1205        cast<CondCodeSDNode>(Node->getOperand(CCOperand))->get();
1206    Action = TLI.getCondCodeAction(CCCode, OpVT);
1207    if (Action == TargetLowering::Legal) {
1208      if (Node->getOpcode() == ISD::SELECT_CC)
1209        Action = TLI.getOperationAction(Node->getOpcode(),
1210                                        Node->getValueType(0));
1211      else
1212        Action = TLI.getOperationAction(Node->getOpcode(), OpVT);
1213    }
1214    break;
1215  }
1216  case ISD::LOAD:
1217  case ISD::STORE:
1218    // FIXME: Model these properly.  LOAD and STORE are complicated, and
1219    // STORE expects the unlegalized operand in some cases.
1220    SimpleFinishLegalizing = false;
1221    break;
1222  case ISD::CALLSEQ_START:
1223  case ISD::CALLSEQ_END:
1224    // FIXME: This shouldn't be necessary.  These nodes have special properties
1225    // dealing with the recursive nature of legalization.  Removing this
1226    // special case should be done as part of making LegalizeDAG non-recursive.
1227    SimpleFinishLegalizing = false;
1228    break;
1229  case ISD::EXTRACT_ELEMENT:
1230  case ISD::FLT_ROUNDS_:
1231  case ISD::SADDO:
1232  case ISD::SSUBO:
1233  case ISD::UADDO:
1234  case ISD::USUBO:
1235  case ISD::SMULO:
1236  case ISD::UMULO:
1237  case ISD::FPOWI:
1238  case ISD::MERGE_VALUES:
1239  case ISD::EH_RETURN:
1240  case ISD::FRAME_TO_ARGS_OFFSET:
1241  case ISD::EH_SJLJ_SETJMP:
1242  case ISD::EH_SJLJ_LONGJMP:
1243    // These operations lie about being legal: when they claim to be legal,
1244    // they should actually be expanded.
1245    Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1246    if (Action == TargetLowering::Legal)
1247      Action = TargetLowering::Expand;
1248    break;
1249  case ISD::INIT_TRAMPOLINE:
1250  case ISD::ADJUST_TRAMPOLINE:
1251  case ISD::FRAMEADDR:
1252  case ISD::RETURNADDR:
1253    // These operations lie about being legal: when they claim to be legal,
1254    // they should actually be custom-lowered.
1255    Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1256    if (Action == TargetLowering::Legal)
1257      Action = TargetLowering::Custom;
1258    break;
1259  case ISD::DEBUGTRAP:
1260    Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1261    if (Action == TargetLowering::Expand) {
1262      // replace ISD::DEBUGTRAP with ISD::TRAP
1263      SDValue NewVal;
1264      NewVal = DAG.getNode(ISD::TRAP, SDLoc(Node), Node->getVTList(),
1265                           Node->getOperand(0));
1266      ReplaceNode(Node, NewVal.getNode());
1267      LegalizeOp(NewVal.getNode());
1268      return;
1269    }
1270    break;
1271
1272  default:
1273    if (Node->getOpcode() >= ISD::BUILTIN_OP_END) {
1274      Action = TargetLowering::Legal;
1275    } else {
1276      Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1277    }
1278    break;
1279  }
1280
1281  if (SimpleFinishLegalizing) {
1282    SDNode *NewNode = Node;
1283    switch (Node->getOpcode()) {
1284    default: break;
1285    case ISD::SHL:
1286    case ISD::SRL:
1287    case ISD::SRA:
1288    case ISD::ROTL:
1289    case ISD::ROTR:
1290      // Legalizing shifts/rotates requires adjusting the shift amount
1291      // to the appropriate width.
1292      if (!Node->getOperand(1).getValueType().isVector()) {
1293        SDValue SAO =
1294          DAG.getShiftAmountOperand(Node->getOperand(0).getValueType(),
1295                                    Node->getOperand(1));
1296        HandleSDNode Handle(SAO);
1297        LegalizeOp(SAO.getNode());
1298        NewNode = DAG.UpdateNodeOperands(Node, Node->getOperand(0),
1299                                         Handle.getValue());
1300      }
1301      break;
1302    case ISD::SRL_PARTS:
1303    case ISD::SRA_PARTS:
1304    case ISD::SHL_PARTS:
1305      // Legalizing shifts/rotates requires adjusting the shift amount
1306      // to the appropriate width.
1307      if (!Node->getOperand(2).getValueType().isVector()) {
1308        SDValue SAO =
1309          DAG.getShiftAmountOperand(Node->getOperand(0).getValueType(),
1310                                    Node->getOperand(2));
1311        HandleSDNode Handle(SAO);
1312        LegalizeOp(SAO.getNode());
1313        NewNode = DAG.UpdateNodeOperands(Node, Node->getOperand(0),
1314                                         Node->getOperand(1),
1315                                         Handle.getValue());
1316      }
1317      break;
1318    }
1319
1320    if (NewNode != Node) {
1321      DAG.ReplaceAllUsesWith(Node, NewNode);
1322      for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
1323        DAG.TransferDbgValues(SDValue(Node, i), SDValue(NewNode, i));
1324      ReplacedNode(Node);
1325      Node = NewNode;
1326    }
1327    switch (Action) {
1328    case TargetLowering::Legal:
1329      return;
1330    case TargetLowering::Custom: {
1331      // FIXME: The handling for custom lowering with multiple results is
1332      // a complete mess.
1333      SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG);
1334      if (Res.getNode()) {
1335        SmallVector<SDValue, 8> ResultVals;
1336        for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i) {
1337          if (e == 1)
1338            ResultVals.push_back(Res);
1339          else
1340            ResultVals.push_back(Res.getValue(i));
1341        }
1342        if (Res.getNode() != Node || Res.getResNo() != 0) {
1343          DAG.ReplaceAllUsesWith(Node, ResultVals.data());
1344          for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
1345            DAG.TransferDbgValues(SDValue(Node, i), ResultVals[i]);
1346          ReplacedNode(Node);
1347        }
1348        return;
1349      }
1350    }
1351      // FALL THROUGH
1352    case TargetLowering::Expand:
1353      ExpandNode(Node);
1354      return;
1355    case TargetLowering::Promote:
1356      PromoteNode(Node);
1357      return;
1358    }
1359  }
1360
1361  switch (Node->getOpcode()) {
1362  default:
1363#ifndef NDEBUG
1364    dbgs() << "NODE: ";
1365    Node->dump( &DAG);
1366    dbgs() << "\n";
1367#endif
1368    llvm_unreachable("Do not know how to legalize this operator!");
1369
1370  case ISD::CALLSEQ_START:
1371  case ISD::CALLSEQ_END:
1372    break;
1373  case ISD::LOAD: {
1374    return LegalizeLoadOps(Node);
1375  }
1376  case ISD::STORE: {
1377    return LegalizeStoreOps(Node);
1378  }
1379  }
1380}
1381
1382SDValue SelectionDAGLegalize::ExpandExtractFromVectorThroughStack(SDValue Op) {
1383  SDValue Vec = Op.getOperand(0);
1384  SDValue Idx = Op.getOperand(1);
1385  SDLoc dl(Op);
1386  // Store the value to a temporary stack slot, then LOAD the returned part.
1387  SDValue StackPtr = DAG.CreateStackTemporary(Vec.getValueType());
1388  SDValue Ch = DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr,
1389                            MachinePointerInfo(), false, false, 0);
1390
1391  // Add the offset to the index.
1392  unsigned EltSize =
1393      Vec.getValueType().getVectorElementType().getSizeInBits()/8;
1394  Idx = DAG.getNode(ISD::MUL, dl, Idx.getValueType(), Idx,
1395                    DAG.getConstant(EltSize, Idx.getValueType()));
1396
1397  if (Idx.getValueType().bitsGT(TLI.getPointerTy()))
1398    Idx = DAG.getNode(ISD::TRUNCATE, dl, TLI.getPointerTy(), Idx);
1399  else
1400    Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
1401
1402  StackPtr = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, StackPtr);
1403
1404  if (Op.getValueType().isVector())
1405    return DAG.getLoad(Op.getValueType(), dl, Ch, StackPtr,MachinePointerInfo(),
1406                       false, false, false, 0);
1407  return DAG.getExtLoad(ISD::EXTLOAD, dl, Op.getValueType(), Ch, StackPtr,
1408                        MachinePointerInfo(),
1409                        Vec.getValueType().getVectorElementType(),
1410                        false, false, 0);
1411}
1412
1413SDValue SelectionDAGLegalize::ExpandInsertToVectorThroughStack(SDValue Op) {
1414  assert(Op.getValueType().isVector() && "Non-vector insert subvector!");
1415
1416  SDValue Vec  = Op.getOperand(0);
1417  SDValue Part = Op.getOperand(1);
1418  SDValue Idx  = Op.getOperand(2);
1419  SDLoc dl(Op);
1420
1421  // Store the value to a temporary stack slot, then LOAD the returned part.
1422
1423  SDValue StackPtr = DAG.CreateStackTemporary(Vec.getValueType());
1424  int FI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
1425  MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(FI);
1426
1427  // First store the whole vector.
1428  SDValue Ch = DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr, PtrInfo,
1429                            false, false, 0);
1430
1431  // Then store the inserted part.
1432
1433  // Add the offset to the index.
1434  unsigned EltSize =
1435      Vec.getValueType().getVectorElementType().getSizeInBits()/8;
1436
1437  Idx = DAG.getNode(ISD::MUL, dl, Idx.getValueType(), Idx,
1438                    DAG.getConstant(EltSize, Idx.getValueType()));
1439
1440  if (Idx.getValueType().bitsGT(TLI.getPointerTy()))
1441    Idx = DAG.getNode(ISD::TRUNCATE, dl, TLI.getPointerTy(), Idx);
1442  else
1443    Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
1444
1445  SDValue SubStackPtr = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx,
1446                                    StackPtr);
1447
1448  // Store the subvector.
1449  Ch = DAG.getStore(DAG.getEntryNode(), dl, Part, SubStackPtr,
1450                    MachinePointerInfo(), false, false, 0);
1451
1452  // Finally, load the updated vector.
1453  return DAG.getLoad(Op.getValueType(), dl, Ch, StackPtr, PtrInfo,
1454                     false, false, false, 0);
1455}
1456
1457SDValue SelectionDAGLegalize::ExpandVectorBuildThroughStack(SDNode* Node) {
1458  // We can't handle this case efficiently.  Allocate a sufficiently
1459  // aligned object on the stack, store each element into it, then load
1460  // the result as a vector.
1461  // Create the stack frame object.
1462  EVT VT = Node->getValueType(0);
1463  EVT EltVT = VT.getVectorElementType();
1464  SDLoc dl(Node);
1465  SDValue FIPtr = DAG.CreateStackTemporary(VT);
1466  int FI = cast<FrameIndexSDNode>(FIPtr.getNode())->getIndex();
1467  MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(FI);
1468
1469  // Emit a store of each element to the stack slot.
1470  SmallVector<SDValue, 8> Stores;
1471  unsigned TypeByteSize = EltVT.getSizeInBits() / 8;
1472  // Store (in the right endianness) the elements to memory.
1473  for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
1474    // Ignore undef elements.
1475    if (Node->getOperand(i).getOpcode() == ISD::UNDEF) continue;
1476
1477    unsigned Offset = TypeByteSize*i;
1478
1479    SDValue Idx = DAG.getConstant(Offset, FIPtr.getValueType());
1480    Idx = DAG.getNode(ISD::ADD, dl, FIPtr.getValueType(), FIPtr, Idx);
1481
1482    // If the destination vector element type is narrower than the source
1483    // element type, only store the bits necessary.
1484    if (EltVT.bitsLT(Node->getOperand(i).getValueType().getScalarType())) {
1485      Stores.push_back(DAG.getTruncStore(DAG.getEntryNode(), dl,
1486                                         Node->getOperand(i), Idx,
1487                                         PtrInfo.getWithOffset(Offset),
1488                                         EltVT, false, false, 0));
1489    } else
1490      Stores.push_back(DAG.getStore(DAG.getEntryNode(), dl,
1491                                    Node->getOperand(i), Idx,
1492                                    PtrInfo.getWithOffset(Offset),
1493                                    false, false, 0));
1494  }
1495
1496  SDValue StoreChain;
1497  if (!Stores.empty())    // Not all undef elements?
1498    StoreChain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
1499                             &Stores[0], Stores.size());
1500  else
1501    StoreChain = DAG.getEntryNode();
1502
1503  // Result is a load from the stack slot.
1504  return DAG.getLoad(VT, dl, StoreChain, FIPtr, PtrInfo,
1505                     false, false, false, 0);
1506}
1507
1508SDValue SelectionDAGLegalize::ExpandFCOPYSIGN(SDNode* Node) {
1509  SDLoc dl(Node);
1510  SDValue Tmp1 = Node->getOperand(0);
1511  SDValue Tmp2 = Node->getOperand(1);
1512
1513  // Get the sign bit of the RHS.  First obtain a value that has the same
1514  // sign as the sign bit, i.e. negative if and only if the sign bit is 1.
1515  SDValue SignBit;
1516  EVT FloatVT = Tmp2.getValueType();
1517  EVT IVT = EVT::getIntegerVT(*DAG.getContext(), FloatVT.getSizeInBits());
1518  if (TLI.isTypeLegal(IVT)) {
1519    // Convert to an integer with the same sign bit.
1520    SignBit = DAG.getNode(ISD::BITCAST, dl, IVT, Tmp2);
1521  } else {
1522    // Store the float to memory, then load the sign part out as an integer.
1523    MVT LoadTy = TLI.getPointerTy();
1524    // First create a temporary that is aligned for both the load and store.
1525    SDValue StackPtr = DAG.CreateStackTemporary(FloatVT, LoadTy);
1526    // Then store the float to it.
1527    SDValue Ch =
1528      DAG.getStore(DAG.getEntryNode(), dl, Tmp2, StackPtr, MachinePointerInfo(),
1529                   false, false, 0);
1530    if (TLI.isBigEndian()) {
1531      assert(FloatVT.isByteSized() && "Unsupported floating point type!");
1532      // Load out a legal integer with the same sign bit as the float.
1533      SignBit = DAG.getLoad(LoadTy, dl, Ch, StackPtr, MachinePointerInfo(),
1534                            false, false, false, 0);
1535    } else { // Little endian
1536      SDValue LoadPtr = StackPtr;
1537      // The float may be wider than the integer we are going to load.  Advance
1538      // the pointer so that the loaded integer will contain the sign bit.
1539      unsigned Strides = (FloatVT.getSizeInBits()-1)/LoadTy.getSizeInBits();
1540      unsigned ByteOffset = (Strides * LoadTy.getSizeInBits()) / 8;
1541      LoadPtr = DAG.getNode(ISD::ADD, dl, LoadPtr.getValueType(),
1542                            LoadPtr,
1543                            DAG.getConstant(ByteOffset, LoadPtr.getValueType()));
1544      // Load a legal integer containing the sign bit.
1545      SignBit = DAG.getLoad(LoadTy, dl, Ch, LoadPtr, MachinePointerInfo(),
1546                            false, false, false, 0);
1547      // Move the sign bit to the top bit of the loaded integer.
1548      unsigned BitShift = LoadTy.getSizeInBits() -
1549        (FloatVT.getSizeInBits() - 8 * ByteOffset);
1550      assert(BitShift < LoadTy.getSizeInBits() && "Pointer advanced wrong?");
1551      if (BitShift)
1552        SignBit = DAG.getNode(ISD::SHL, dl, LoadTy, SignBit,
1553                              DAG.getConstant(BitShift,
1554                                 TLI.getShiftAmountTy(SignBit.getValueType())));
1555    }
1556  }
1557  // Now get the sign bit proper, by seeing whether the value is negative.
1558  SignBit = DAG.getSetCC(dl, getSetCCResultType(SignBit.getValueType()),
1559                         SignBit, DAG.getConstant(0, SignBit.getValueType()),
1560                         ISD::SETLT);
1561  // Get the absolute value of the result.
1562  SDValue AbsVal = DAG.getNode(ISD::FABS, dl, Tmp1.getValueType(), Tmp1);
1563  // Select between the nabs and abs value based on the sign bit of
1564  // the input.
1565  return DAG.getSelect(dl, AbsVal.getValueType(), SignBit,
1566                       DAG.getNode(ISD::FNEG, dl, AbsVal.getValueType(), AbsVal),
1567                       AbsVal);
1568}
1569
1570void SelectionDAGLegalize::ExpandDYNAMIC_STACKALLOC(SDNode* Node,
1571                                           SmallVectorImpl<SDValue> &Results) {
1572  unsigned SPReg = TLI.getStackPointerRegisterToSaveRestore();
1573  assert(SPReg && "Target cannot require DYNAMIC_STACKALLOC expansion and"
1574          " not tell us which reg is the stack pointer!");
1575  SDLoc dl(Node);
1576  EVT VT = Node->getValueType(0);
1577  SDValue Tmp1 = SDValue(Node, 0);
1578  SDValue Tmp2 = SDValue(Node, 1);
1579  SDValue Tmp3 = Node->getOperand(2);
1580  SDValue Chain = Tmp1.getOperand(0);
1581
1582  // Chain the dynamic stack allocation so that it doesn't modify the stack
1583  // pointer when other instructions are using the stack.
1584  Chain = DAG.getCALLSEQ_START(Chain, DAG.getIntPtrConstant(0, true),
1585                               SDLoc(Node));
1586
1587  SDValue Size  = Tmp2.getOperand(1);
1588  SDValue SP = DAG.getCopyFromReg(Chain, dl, SPReg, VT);
1589  Chain = SP.getValue(1);
1590  unsigned Align = cast<ConstantSDNode>(Tmp3)->getZExtValue();
1591  unsigned StackAlign = TM.getFrameLowering()->getStackAlignment();
1592  Tmp1 = DAG.getNode(ISD::SUB, dl, VT, SP, Size);       // Value
1593  if (Align > StackAlign)
1594    Tmp1 = DAG.getNode(ISD::AND, dl, VT, Tmp1,
1595                       DAG.getConstant(-(uint64_t)Align, VT));
1596  Chain = DAG.getCopyToReg(Chain, dl, SPReg, Tmp1);     // Output chain
1597
1598  Tmp2 = DAG.getCALLSEQ_END(Chain,  DAG.getIntPtrConstant(0, true),
1599                            DAG.getIntPtrConstant(0, true), SDValue(),
1600                            SDLoc(Node));
1601
1602  Results.push_back(Tmp1);
1603  Results.push_back(Tmp2);
1604}
1605
1606/// LegalizeSetCCCondCode - Legalize a SETCC with given LHS and RHS and
1607/// condition code CC on the current target.
1608/// If the SETCC has been legalized using AND / OR, then the legalized node
1609/// will be stored in LHS.  RHS and CC will be set to SDValue().
1610/// If the SETCC has been legalized by using getSetCCSwappedOperands(),
1611/// then the values of LHS and RHS will be swapped and CC will be set to the
1612/// new condition.
1613/// \returns true if the SetCC has been legalized, false if it hasn't.
1614bool SelectionDAGLegalize::LegalizeSetCCCondCode(EVT VT,
1615                                                 SDValue &LHS, SDValue &RHS,
1616                                                 SDValue &CC,
1617                                                 SDLoc dl) {
1618  MVT OpVT = LHS.getSimpleValueType();
1619  ISD::CondCode CCCode = cast<CondCodeSDNode>(CC)->get();
1620  switch (TLI.getCondCodeAction(CCCode, OpVT)) {
1621  default: llvm_unreachable("Unknown condition code action!");
1622  case TargetLowering::Legal:
1623    // Nothing to do.
1624    break;
1625  case TargetLowering::Expand: {
1626    ISD::CondCode InvCC = ISD::getSetCCSwappedOperands(CCCode);
1627    if (TLI.isCondCodeLegal(InvCC, OpVT)) {
1628      std::swap(LHS, RHS);
1629      CC = DAG.getCondCode(InvCC);
1630      return true;
1631    }
1632    ISD::CondCode CC1 = ISD::SETCC_INVALID, CC2 = ISD::SETCC_INVALID;
1633    unsigned Opc = 0;
1634    switch (CCCode) {
1635    default: llvm_unreachable("Don't know how to expand this condition!");
1636    case ISD::SETO:
1637        assert(TLI.getCondCodeAction(ISD::SETOEQ, OpVT)
1638            == TargetLowering::Legal
1639            && "If SETO is expanded, SETOEQ must be legal!");
1640        CC1 = ISD::SETOEQ; CC2 = ISD::SETOEQ; Opc = ISD::AND; break;
1641    case ISD::SETUO:
1642        assert(TLI.getCondCodeAction(ISD::SETUNE, OpVT)
1643            == TargetLowering::Legal
1644            && "If SETUO is expanded, SETUNE must be legal!");
1645        CC1 = ISD::SETUNE; CC2 = ISD::SETUNE; Opc = ISD::OR;  break;
1646    case ISD::SETOEQ:
1647    case ISD::SETOGT:
1648    case ISD::SETOGE:
1649    case ISD::SETOLT:
1650    case ISD::SETOLE:
1651    case ISD::SETONE:
1652    case ISD::SETUEQ:
1653    case ISD::SETUNE:
1654    case ISD::SETUGT:
1655    case ISD::SETUGE:
1656    case ISD::SETULT:
1657    case ISD::SETULE:
1658        // If we are floating point, assign and break, otherwise fall through.
1659        if (!OpVT.isInteger()) {
1660          // We can use the 4th bit to tell if we are the unordered
1661          // or ordered version of the opcode.
1662          CC2 = ((unsigned)CCCode & 0x8U) ? ISD::SETUO : ISD::SETO;
1663          Opc = ((unsigned)CCCode & 0x8U) ? ISD::OR : ISD::AND;
1664          CC1 = (ISD::CondCode)(((int)CCCode & 0x7) | 0x10);
1665          break;
1666        }
1667        // Fallthrough if we are unsigned integer.
1668    case ISD::SETLE:
1669    case ISD::SETGT:
1670    case ISD::SETGE:
1671    case ISD::SETLT:
1672    case ISD::SETNE:
1673    case ISD::SETEQ:
1674      // We only support using the inverted operation, which is computed above
1675      // and not a different manner of supporting expanding these cases.
1676      llvm_unreachable("Don't know how to expand this condition!");
1677    }
1678
1679    SDValue SetCC1, SetCC2;
1680    if (CCCode != ISD::SETO && CCCode != ISD::SETUO) {
1681      // If we aren't the ordered or unorder operation,
1682      // then the pattern is (LHS CC1 RHS) Opc (LHS CC2 RHS).
1683      SetCC1 = DAG.getSetCC(dl, VT, LHS, RHS, CC1);
1684      SetCC2 = DAG.getSetCC(dl, VT, LHS, RHS, CC2);
1685    } else {
1686      // Otherwise, the pattern is (LHS CC1 LHS) Opc (RHS CC2 RHS)
1687      SetCC1 = DAG.getSetCC(dl, VT, LHS, LHS, CC1);
1688      SetCC2 = DAG.getSetCC(dl, VT, RHS, RHS, CC2);
1689    }
1690    LHS = DAG.getNode(Opc, dl, VT, SetCC1, SetCC2);
1691    RHS = SDValue();
1692    CC  = SDValue();
1693    return true;
1694  }
1695  }
1696  return false;
1697}
1698
1699/// EmitStackConvert - Emit a store/load combination to the stack.  This stores
1700/// SrcOp to a stack slot of type SlotVT, truncating it if needed.  It then does
1701/// a load from the stack slot to DestVT, extending it if needed.
1702/// The resultant code need not be legal.
1703SDValue SelectionDAGLegalize::EmitStackConvert(SDValue SrcOp,
1704                                               EVT SlotVT,
1705                                               EVT DestVT,
1706                                               SDLoc dl) {
1707  // Create the stack frame object.
1708  unsigned SrcAlign =
1709    TLI.getDataLayout()->getPrefTypeAlignment(SrcOp.getValueType().
1710                                              getTypeForEVT(*DAG.getContext()));
1711  SDValue FIPtr = DAG.CreateStackTemporary(SlotVT, SrcAlign);
1712
1713  FrameIndexSDNode *StackPtrFI = cast<FrameIndexSDNode>(FIPtr);
1714  int SPFI = StackPtrFI->getIndex();
1715  MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(SPFI);
1716
1717  unsigned SrcSize = SrcOp.getValueType().getSizeInBits();
1718  unsigned SlotSize = SlotVT.getSizeInBits();
1719  unsigned DestSize = DestVT.getSizeInBits();
1720  Type *DestType = DestVT.getTypeForEVT(*DAG.getContext());
1721  unsigned DestAlign = TLI.getDataLayout()->getPrefTypeAlignment(DestType);
1722
1723  // Emit a store to the stack slot.  Use a truncstore if the input value is
1724  // later than DestVT.
1725  SDValue Store;
1726
1727  if (SrcSize > SlotSize)
1728    Store = DAG.getTruncStore(DAG.getEntryNode(), dl, SrcOp, FIPtr,
1729                              PtrInfo, SlotVT, false, false, SrcAlign);
1730  else {
1731    assert(SrcSize == SlotSize && "Invalid store");
1732    Store = DAG.getStore(DAG.getEntryNode(), dl, SrcOp, FIPtr,
1733                         PtrInfo, false, false, SrcAlign);
1734  }
1735
1736  // Result is a load from the stack slot.
1737  if (SlotSize == DestSize)
1738    return DAG.getLoad(DestVT, dl, Store, FIPtr, PtrInfo,
1739                       false, false, false, DestAlign);
1740
1741  assert(SlotSize < DestSize && "Unknown extension!");
1742  return DAG.getExtLoad(ISD::EXTLOAD, dl, DestVT, Store, FIPtr,
1743                        PtrInfo, SlotVT, false, false, DestAlign);
1744}
1745
1746SDValue SelectionDAGLegalize::ExpandSCALAR_TO_VECTOR(SDNode *Node) {
1747  SDLoc dl(Node);
1748  // Create a vector sized/aligned stack slot, store the value to element #0,
1749  // then load the whole vector back out.
1750  SDValue StackPtr = DAG.CreateStackTemporary(Node->getValueType(0));
1751
1752  FrameIndexSDNode *StackPtrFI = cast<FrameIndexSDNode>(StackPtr);
1753  int SPFI = StackPtrFI->getIndex();
1754
1755  SDValue Ch = DAG.getTruncStore(DAG.getEntryNode(), dl, Node->getOperand(0),
1756                                 StackPtr,
1757                                 MachinePointerInfo::getFixedStack(SPFI),
1758                                 Node->getValueType(0).getVectorElementType(),
1759                                 false, false, 0);
1760  return DAG.getLoad(Node->getValueType(0), dl, Ch, StackPtr,
1761                     MachinePointerInfo::getFixedStack(SPFI),
1762                     false, false, false, 0);
1763}
1764
1765
1766/// ExpandBUILD_VECTOR - Expand a BUILD_VECTOR node on targets that don't
1767/// support the operation, but do support the resultant vector type.
1768SDValue SelectionDAGLegalize::ExpandBUILD_VECTOR(SDNode *Node) {
1769  unsigned NumElems = Node->getNumOperands();
1770  SDValue Value1, Value2;
1771  SDLoc dl(Node);
1772  EVT VT = Node->getValueType(0);
1773  EVT OpVT = Node->getOperand(0).getValueType();
1774  EVT EltVT = VT.getVectorElementType();
1775
1776  // If the only non-undef value is the low element, turn this into a
1777  // SCALAR_TO_VECTOR node.  If this is { X, X, X, X }, determine X.
1778  bool isOnlyLowElement = true;
1779  bool MoreThanTwoValues = false;
1780  bool isConstant = true;
1781  for (unsigned i = 0; i < NumElems; ++i) {
1782    SDValue V = Node->getOperand(i);
1783    if (V.getOpcode() == ISD::UNDEF)
1784      continue;
1785    if (i > 0)
1786      isOnlyLowElement = false;
1787    if (!isa<ConstantFPSDNode>(V) && !isa<ConstantSDNode>(V))
1788      isConstant = false;
1789
1790    if (!Value1.getNode()) {
1791      Value1 = V;
1792    } else if (!Value2.getNode()) {
1793      if (V != Value1)
1794        Value2 = V;
1795    } else if (V != Value1 && V != Value2) {
1796      MoreThanTwoValues = true;
1797    }
1798  }
1799
1800  if (!Value1.getNode())
1801    return DAG.getUNDEF(VT);
1802
1803  if (isOnlyLowElement)
1804    return DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Node->getOperand(0));
1805
1806  // If all elements are constants, create a load from the constant pool.
1807  if (isConstant) {
1808    SmallVector<Constant*, 16> CV;
1809    for (unsigned i = 0, e = NumElems; i != e; ++i) {
1810      if (ConstantFPSDNode *V =
1811          dyn_cast<ConstantFPSDNode>(Node->getOperand(i))) {
1812        CV.push_back(const_cast<ConstantFP *>(V->getConstantFPValue()));
1813      } else if (ConstantSDNode *V =
1814                 dyn_cast<ConstantSDNode>(Node->getOperand(i))) {
1815        if (OpVT==EltVT)
1816          CV.push_back(const_cast<ConstantInt *>(V->getConstantIntValue()));
1817        else {
1818          // If OpVT and EltVT don't match, EltVT is not legal and the
1819          // element values have been promoted/truncated earlier.  Undo this;
1820          // we don't want a v16i8 to become a v16i32 for example.
1821          const ConstantInt *CI = V->getConstantIntValue();
1822          CV.push_back(ConstantInt::get(EltVT.getTypeForEVT(*DAG.getContext()),
1823                                        CI->getZExtValue()));
1824        }
1825      } else {
1826        assert(Node->getOperand(i).getOpcode() == ISD::UNDEF);
1827        Type *OpNTy = EltVT.getTypeForEVT(*DAG.getContext());
1828        CV.push_back(UndefValue::get(OpNTy));
1829      }
1830    }
1831    Constant *CP = ConstantVector::get(CV);
1832    SDValue CPIdx = DAG.getConstantPool(CP, TLI.getPointerTy());
1833    unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
1834    return DAG.getLoad(VT, dl, DAG.getEntryNode(), CPIdx,
1835                       MachinePointerInfo::getConstantPool(),
1836                       false, false, false, Alignment);
1837  }
1838
1839  if (!MoreThanTwoValues) {
1840    SmallVector<int, 8> ShuffleVec(NumElems, -1);
1841    for (unsigned i = 0; i < NumElems; ++i) {
1842      SDValue V = Node->getOperand(i);
1843      if (V.getOpcode() == ISD::UNDEF)
1844        continue;
1845      ShuffleVec[i] = V == Value1 ? 0 : NumElems;
1846    }
1847    if (TLI.isShuffleMaskLegal(ShuffleVec, Node->getValueType(0))) {
1848      // Get the splatted value into the low element of a vector register.
1849      SDValue Vec1 = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Value1);
1850      SDValue Vec2;
1851      if (Value2.getNode())
1852        Vec2 = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Value2);
1853      else
1854        Vec2 = DAG.getUNDEF(VT);
1855
1856      // Return shuffle(LowValVec, undef, <0,0,0,0>)
1857      return DAG.getVectorShuffle(VT, dl, Vec1, Vec2, ShuffleVec.data());
1858    }
1859  }
1860
1861  // Otherwise, we can't handle this case efficiently.
1862  return ExpandVectorBuildThroughStack(Node);
1863}
1864
1865// ExpandLibCall - Expand a node into a call to a libcall.  If the result value
1866// does not fit into a register, return the lo part and set the hi part to the
1867// by-reg argument.  If it does fit into a single register, return the result
1868// and leave the Hi part unset.
1869SDValue SelectionDAGLegalize::ExpandLibCall(RTLIB::Libcall LC, SDNode *Node,
1870                                            bool isSigned) {
1871  TargetLowering::ArgListTy Args;
1872  TargetLowering::ArgListEntry Entry;
1873  for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
1874    EVT ArgVT = Node->getOperand(i).getValueType();
1875    Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
1876    Entry.Node = Node->getOperand(i); Entry.Ty = ArgTy;
1877    Entry.isSExt = isSigned;
1878    Entry.isZExt = !isSigned;
1879    Args.push_back(Entry);
1880  }
1881  SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
1882                                         TLI.getPointerTy());
1883
1884  Type *RetTy = Node->getValueType(0).getTypeForEVT(*DAG.getContext());
1885
1886  // By default, the input chain to this libcall is the entry node of the
1887  // function. If the libcall is going to be emitted as a tail call then
1888  // TLI.isUsedByReturnOnly will change it to the right chain if the return
1889  // node which is being folded has a non-entry input chain.
1890  SDValue InChain = DAG.getEntryNode();
1891
1892  // isTailCall may be true since the callee does not reference caller stack
1893  // frame. Check if it's in the right position.
1894  SDValue TCChain = InChain;
1895  bool isTailCall = TLI.isInTailCallPosition(DAG, Node, TCChain);
1896  if (isTailCall)
1897    InChain = TCChain;
1898
1899  TargetLowering::
1900  CallLoweringInfo CLI(InChain, RetTy, isSigned, !isSigned, false, false,
1901                    0, TLI.getLibcallCallingConv(LC), isTailCall,
1902                    /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
1903                    Callee, Args, DAG, SDLoc(Node));
1904  std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI);
1905
1906
1907  if (!CallInfo.second.getNode())
1908    // It's a tailcall, return the chain (which is the DAG root).
1909    return DAG.getRoot();
1910
1911  return CallInfo.first;
1912}
1913
1914/// ExpandLibCall - Generate a libcall taking the given operands as arguments
1915/// and returning a result of type RetVT.
1916SDValue SelectionDAGLegalize::ExpandLibCall(RTLIB::Libcall LC, EVT RetVT,
1917                                            const SDValue *Ops, unsigned NumOps,
1918                                            bool isSigned, SDLoc dl) {
1919  TargetLowering::ArgListTy Args;
1920  Args.reserve(NumOps);
1921
1922  TargetLowering::ArgListEntry Entry;
1923  for (unsigned i = 0; i != NumOps; ++i) {
1924    Entry.Node = Ops[i];
1925    Entry.Ty = Entry.Node.getValueType().getTypeForEVT(*DAG.getContext());
1926    Entry.isSExt = isSigned;
1927    Entry.isZExt = !isSigned;
1928    Args.push_back(Entry);
1929  }
1930  SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
1931                                         TLI.getPointerTy());
1932
1933  Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
1934  TargetLowering::
1935  CallLoweringInfo CLI(DAG.getEntryNode(), RetTy, isSigned, !isSigned, false,
1936                       false, 0, TLI.getLibcallCallingConv(LC),
1937                       /*isTailCall=*/false,
1938                  /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
1939                  Callee, Args, DAG, dl);
1940  std::pair<SDValue,SDValue> CallInfo = TLI.LowerCallTo(CLI);
1941
1942  return CallInfo.first;
1943}
1944
1945// ExpandChainLibCall - Expand a node into a call to a libcall. Similar to
1946// ExpandLibCall except that the first operand is the in-chain.
1947std::pair<SDValue, SDValue>
1948SelectionDAGLegalize::ExpandChainLibCall(RTLIB::Libcall LC,
1949                                         SDNode *Node,
1950                                         bool isSigned) {
1951  SDValue InChain = Node->getOperand(0);
1952
1953  TargetLowering::ArgListTy Args;
1954  TargetLowering::ArgListEntry Entry;
1955  for (unsigned i = 1, e = Node->getNumOperands(); i != e; ++i) {
1956    EVT ArgVT = Node->getOperand(i).getValueType();
1957    Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
1958    Entry.Node = Node->getOperand(i);
1959    Entry.Ty = ArgTy;
1960    Entry.isSExt = isSigned;
1961    Entry.isZExt = !isSigned;
1962    Args.push_back(Entry);
1963  }
1964  SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
1965                                         TLI.getPointerTy());
1966
1967  Type *RetTy = Node->getValueType(0).getTypeForEVT(*DAG.getContext());
1968  TargetLowering::
1969  CallLoweringInfo CLI(InChain, RetTy, isSigned, !isSigned, false, false,
1970                    0, TLI.getLibcallCallingConv(LC), /*isTailCall=*/false,
1971                    /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
1972                    Callee, Args, DAG, SDLoc(Node));
1973  std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI);
1974
1975  return CallInfo;
1976}
1977
1978SDValue SelectionDAGLegalize::ExpandFPLibCall(SDNode* Node,
1979                                              RTLIB::Libcall Call_F32,
1980                                              RTLIB::Libcall Call_F64,
1981                                              RTLIB::Libcall Call_F80,
1982                                              RTLIB::Libcall Call_F128,
1983                                              RTLIB::Libcall Call_PPCF128) {
1984  RTLIB::Libcall LC;
1985  switch (Node->getSimpleValueType(0).SimpleTy) {
1986  default: llvm_unreachable("Unexpected request for libcall!");
1987  case MVT::f32: LC = Call_F32; break;
1988  case MVT::f64: LC = Call_F64; break;
1989  case MVT::f80: LC = Call_F80; break;
1990  case MVT::f128: LC = Call_F128; break;
1991  case MVT::ppcf128: LC = Call_PPCF128; break;
1992  }
1993  return ExpandLibCall(LC, Node, false);
1994}
1995
1996SDValue SelectionDAGLegalize::ExpandIntLibCall(SDNode* Node, bool isSigned,
1997                                               RTLIB::Libcall Call_I8,
1998                                               RTLIB::Libcall Call_I16,
1999                                               RTLIB::Libcall Call_I32,
2000                                               RTLIB::Libcall Call_I64,
2001                                               RTLIB::Libcall Call_I128) {
2002  RTLIB::Libcall LC;
2003  switch (Node->getSimpleValueType(0).SimpleTy) {
2004  default: llvm_unreachable("Unexpected request for libcall!");
2005  case MVT::i8:   LC = Call_I8; break;
2006  case MVT::i16:  LC = Call_I16; break;
2007  case MVT::i32:  LC = Call_I32; break;
2008  case MVT::i64:  LC = Call_I64; break;
2009  case MVT::i128: LC = Call_I128; break;
2010  }
2011  return ExpandLibCall(LC, Node, isSigned);
2012}
2013
2014/// isDivRemLibcallAvailable - Return true if divmod libcall is available.
2015static bool isDivRemLibcallAvailable(SDNode *Node, bool isSigned,
2016                                     const TargetLowering &TLI) {
2017  RTLIB::Libcall LC;
2018  switch (Node->getSimpleValueType(0).SimpleTy) {
2019  default: llvm_unreachable("Unexpected request for libcall!");
2020  case MVT::i8:   LC= isSigned ? RTLIB::SDIVREM_I8  : RTLIB::UDIVREM_I8;  break;
2021  case MVT::i16:  LC= isSigned ? RTLIB::SDIVREM_I16 : RTLIB::UDIVREM_I16; break;
2022  case MVT::i32:  LC= isSigned ? RTLIB::SDIVREM_I32 : RTLIB::UDIVREM_I32; break;
2023  case MVT::i64:  LC= isSigned ? RTLIB::SDIVREM_I64 : RTLIB::UDIVREM_I64; break;
2024  case MVT::i128: LC= isSigned ? RTLIB::SDIVREM_I128:RTLIB::UDIVREM_I128; break;
2025  }
2026
2027  return TLI.getLibcallName(LC) != 0;
2028}
2029
2030/// useDivRem - Only issue divrem libcall if both quotient and remainder are
2031/// needed.
2032static bool useDivRem(SDNode *Node, bool isSigned, bool isDIV) {
2033  // The other use might have been replaced with a divrem already.
2034  unsigned DivRemOpc = isSigned ? ISD::SDIVREM : ISD::UDIVREM;
2035  unsigned OtherOpcode = 0;
2036  if (isSigned)
2037    OtherOpcode = isDIV ? ISD::SREM : ISD::SDIV;
2038  else
2039    OtherOpcode = isDIV ? ISD::UREM : ISD::UDIV;
2040
2041  SDValue Op0 = Node->getOperand(0);
2042  SDValue Op1 = Node->getOperand(1);
2043  for (SDNode::use_iterator UI = Op0.getNode()->use_begin(),
2044         UE = Op0.getNode()->use_end(); UI != UE; ++UI) {
2045    SDNode *User = *UI;
2046    if (User == Node)
2047      continue;
2048    if ((User->getOpcode() == OtherOpcode || User->getOpcode() == DivRemOpc) &&
2049        User->getOperand(0) == Op0 &&
2050        User->getOperand(1) == Op1)
2051      return true;
2052  }
2053  return false;
2054}
2055
2056/// ExpandDivRemLibCall - Issue libcalls to __{u}divmod to compute div / rem
2057/// pairs.
2058void
2059SelectionDAGLegalize::ExpandDivRemLibCall(SDNode *Node,
2060                                          SmallVectorImpl<SDValue> &Results) {
2061  unsigned Opcode = Node->getOpcode();
2062  bool isSigned = Opcode == ISD::SDIVREM;
2063
2064  RTLIB::Libcall LC;
2065  switch (Node->getSimpleValueType(0).SimpleTy) {
2066  default: llvm_unreachable("Unexpected request for libcall!");
2067  case MVT::i8:   LC= isSigned ? RTLIB::SDIVREM_I8  : RTLIB::UDIVREM_I8;  break;
2068  case MVT::i16:  LC= isSigned ? RTLIB::SDIVREM_I16 : RTLIB::UDIVREM_I16; break;
2069  case MVT::i32:  LC= isSigned ? RTLIB::SDIVREM_I32 : RTLIB::UDIVREM_I32; break;
2070  case MVT::i64:  LC= isSigned ? RTLIB::SDIVREM_I64 : RTLIB::UDIVREM_I64; break;
2071  case MVT::i128: LC= isSigned ? RTLIB::SDIVREM_I128:RTLIB::UDIVREM_I128; break;
2072  }
2073
2074  // The input chain to this libcall is the entry node of the function.
2075  // Legalizing the call will automatically add the previous call to the
2076  // dependence.
2077  SDValue InChain = DAG.getEntryNode();
2078
2079  EVT RetVT = Node->getValueType(0);
2080  Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
2081
2082  TargetLowering::ArgListTy Args;
2083  TargetLowering::ArgListEntry Entry;
2084  for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
2085    EVT ArgVT = Node->getOperand(i).getValueType();
2086    Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
2087    Entry.Node = Node->getOperand(i); Entry.Ty = ArgTy;
2088    Entry.isSExt = isSigned;
2089    Entry.isZExt = !isSigned;
2090    Args.push_back(Entry);
2091  }
2092
2093  // Also pass the return address of the remainder.
2094  SDValue FIPtr = DAG.CreateStackTemporary(RetVT);
2095  Entry.Node = FIPtr;
2096  Entry.Ty = RetTy->getPointerTo();
2097  Entry.isSExt = isSigned;
2098  Entry.isZExt = !isSigned;
2099  Args.push_back(Entry);
2100
2101  SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
2102                                         TLI.getPointerTy());
2103
2104  SDLoc dl(Node);
2105  TargetLowering::
2106  CallLoweringInfo CLI(InChain, RetTy, isSigned, !isSigned, false, false,
2107                    0, TLI.getLibcallCallingConv(LC), /*isTailCall=*/false,
2108                    /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
2109                    Callee, Args, DAG, dl);
2110  std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI);
2111
2112  // Remainder is loaded back from the stack frame.
2113  SDValue Rem = DAG.getLoad(RetVT, dl, CallInfo.second, FIPtr,
2114                            MachinePointerInfo(), false, false, false, 0);
2115  Results.push_back(CallInfo.first);
2116  Results.push_back(Rem);
2117}
2118
2119/// isSinCosLibcallAvailable - Return true if sincos libcall is available.
2120static bool isSinCosLibcallAvailable(SDNode *Node, const TargetLowering &TLI) {
2121  RTLIB::Libcall LC;
2122  switch (Node->getSimpleValueType(0).SimpleTy) {
2123  default: llvm_unreachable("Unexpected request for libcall!");
2124  case MVT::f32:     LC = RTLIB::SINCOS_F32; break;
2125  case MVT::f64:     LC = RTLIB::SINCOS_F64; break;
2126  case MVT::f80:     LC = RTLIB::SINCOS_F80; break;
2127  case MVT::f128:    LC = RTLIB::SINCOS_F128; break;
2128  case MVT::ppcf128: LC = RTLIB::SINCOS_PPCF128; break;
2129  }
2130  return TLI.getLibcallName(LC) != 0;
2131}
2132
2133/// canCombineSinCosLibcall - Return true if sincos libcall is available and
2134/// can be used to combine sin and cos.
2135static bool canCombineSinCosLibcall(SDNode *Node, const TargetLowering &TLI,
2136                                    const TargetMachine &TM) {
2137  if (!isSinCosLibcallAvailable(Node, TLI))
2138    return false;
2139  // GNU sin/cos functions set errno while sincos does not. Therefore
2140  // combining sin and cos is only safe if unsafe-fpmath is enabled.
2141  bool isGNU = Triple(TM.getTargetTriple()).getEnvironment() == Triple::GNU;
2142  if (isGNU && !TM.Options.UnsafeFPMath)
2143    return false;
2144  return true;
2145}
2146
2147/// useSinCos - Only issue sincos libcall if both sin and cos are
2148/// needed.
2149static bool useSinCos(SDNode *Node) {
2150  unsigned OtherOpcode = Node->getOpcode() == ISD::FSIN
2151    ? ISD::FCOS : ISD::FSIN;
2152
2153  SDValue Op0 = Node->getOperand(0);
2154  for (SDNode::use_iterator UI = Op0.getNode()->use_begin(),
2155       UE = Op0.getNode()->use_end(); UI != UE; ++UI) {
2156    SDNode *User = *UI;
2157    if (User == Node)
2158      continue;
2159    // The other user might have been turned into sincos already.
2160    if (User->getOpcode() == OtherOpcode || User->getOpcode() == ISD::FSINCOS)
2161      return true;
2162  }
2163  return false;
2164}
2165
2166/// ExpandSinCosLibCall - Issue libcalls to sincos to compute sin / cos
2167/// pairs.
2168void
2169SelectionDAGLegalize::ExpandSinCosLibCall(SDNode *Node,
2170                                          SmallVectorImpl<SDValue> &Results) {
2171  RTLIB::Libcall LC;
2172  switch (Node->getSimpleValueType(0).SimpleTy) {
2173  default: llvm_unreachable("Unexpected request for libcall!");
2174  case MVT::f32:     LC = RTLIB::SINCOS_F32; break;
2175  case MVT::f64:     LC = RTLIB::SINCOS_F64; break;
2176  case MVT::f80:     LC = RTLIB::SINCOS_F80; break;
2177  case MVT::f128:    LC = RTLIB::SINCOS_F128; break;
2178  case MVT::ppcf128: LC = RTLIB::SINCOS_PPCF128; break;
2179  }
2180
2181  // The input chain to this libcall is the entry node of the function.
2182  // Legalizing the call will automatically add the previous call to the
2183  // dependence.
2184  SDValue InChain = DAG.getEntryNode();
2185
2186  EVT RetVT = Node->getValueType(0);
2187  Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
2188
2189  TargetLowering::ArgListTy Args;
2190  TargetLowering::ArgListEntry Entry;
2191
2192  // Pass the argument.
2193  Entry.Node = Node->getOperand(0);
2194  Entry.Ty = RetTy;
2195  Entry.isSExt = false;
2196  Entry.isZExt = false;
2197  Args.push_back(Entry);
2198
2199  // Pass the return address of sin.
2200  SDValue SinPtr = DAG.CreateStackTemporary(RetVT);
2201  Entry.Node = SinPtr;
2202  Entry.Ty = RetTy->getPointerTo();
2203  Entry.isSExt = false;
2204  Entry.isZExt = false;
2205  Args.push_back(Entry);
2206
2207  // Also pass the return address of the cos.
2208  SDValue CosPtr = DAG.CreateStackTemporary(RetVT);
2209  Entry.Node = CosPtr;
2210  Entry.Ty = RetTy->getPointerTo();
2211  Entry.isSExt = false;
2212  Entry.isZExt = false;
2213  Args.push_back(Entry);
2214
2215  SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
2216                                         TLI.getPointerTy());
2217
2218  SDLoc dl(Node);
2219  TargetLowering::
2220  CallLoweringInfo CLI(InChain, Type::getVoidTy(*DAG.getContext()),
2221                       false, false, false, false,
2222                       0, TLI.getLibcallCallingConv(LC), /*isTailCall=*/false,
2223                       /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
2224                       Callee, Args, DAG, dl);
2225  std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI);
2226
2227  Results.push_back(DAG.getLoad(RetVT, dl, CallInfo.second, SinPtr,
2228                                MachinePointerInfo(), false, false, false, 0));
2229  Results.push_back(DAG.getLoad(RetVT, dl, CallInfo.second, CosPtr,
2230                                MachinePointerInfo(), false, false, false, 0));
2231}
2232
2233/// ExpandLegalINT_TO_FP - This function is responsible for legalizing a
2234/// INT_TO_FP operation of the specified operand when the target requests that
2235/// we expand it.  At this point, we know that the result and operand types are
2236/// legal for the target.
2237SDValue SelectionDAGLegalize::ExpandLegalINT_TO_FP(bool isSigned,
2238                                                   SDValue Op0,
2239                                                   EVT DestVT,
2240                                                   SDLoc dl) {
2241  if (Op0.getValueType() == MVT::i32 && TLI.isTypeLegal(MVT::f64)) {
2242    // simple 32-bit [signed|unsigned] integer to float/double expansion
2243
2244    // Get the stack frame index of a 8 byte buffer.
2245    SDValue StackSlot = DAG.CreateStackTemporary(MVT::f64);
2246
2247    // word offset constant for Hi/Lo address computation
2248    SDValue WordOff = DAG.getConstant(sizeof(int), StackSlot.getValueType());
2249    // set up Hi and Lo (into buffer) address based on endian
2250    SDValue Hi = StackSlot;
2251    SDValue Lo = DAG.getNode(ISD::ADD, dl, StackSlot.getValueType(),
2252                             StackSlot, WordOff);
2253    if (TLI.isLittleEndian())
2254      std::swap(Hi, Lo);
2255
2256    // if signed map to unsigned space
2257    SDValue Op0Mapped;
2258    if (isSigned) {
2259      // constant used to invert sign bit (signed to unsigned mapping)
2260      SDValue SignBit = DAG.getConstant(0x80000000u, MVT::i32);
2261      Op0Mapped = DAG.getNode(ISD::XOR, dl, MVT::i32, Op0, SignBit);
2262    } else {
2263      Op0Mapped = Op0;
2264    }
2265    // store the lo of the constructed double - based on integer input
2266    SDValue Store1 = DAG.getStore(DAG.getEntryNode(), dl,
2267                                  Op0Mapped, Lo, MachinePointerInfo(),
2268                                  false, false, 0);
2269    // initial hi portion of constructed double
2270    SDValue InitialHi = DAG.getConstant(0x43300000u, MVT::i32);
2271    // store the hi of the constructed double - biased exponent
2272    SDValue Store2 = DAG.getStore(Store1, dl, InitialHi, Hi,
2273                                  MachinePointerInfo(),
2274                                  false, false, 0);
2275    // load the constructed double
2276    SDValue Load = DAG.getLoad(MVT::f64, dl, Store2, StackSlot,
2277                               MachinePointerInfo(), false, false, false, 0);
2278    // FP constant to bias correct the final result
2279    SDValue Bias = DAG.getConstantFP(isSigned ?
2280                                     BitsToDouble(0x4330000080000000ULL) :
2281                                     BitsToDouble(0x4330000000000000ULL),
2282                                     MVT::f64);
2283    // subtract the bias
2284    SDValue Sub = DAG.getNode(ISD::FSUB, dl, MVT::f64, Load, Bias);
2285    // final result
2286    SDValue Result;
2287    // handle final rounding
2288    if (DestVT == MVT::f64) {
2289      // do nothing
2290      Result = Sub;
2291    } else if (DestVT.bitsLT(MVT::f64)) {
2292      Result = DAG.getNode(ISD::FP_ROUND, dl, DestVT, Sub,
2293                           DAG.getIntPtrConstant(0));
2294    } else if (DestVT.bitsGT(MVT::f64)) {
2295      Result = DAG.getNode(ISD::FP_EXTEND, dl, DestVT, Sub);
2296    }
2297    return Result;
2298  }
2299  assert(!isSigned && "Legalize cannot Expand SINT_TO_FP for i64 yet");
2300  // Code below here assumes !isSigned without checking again.
2301
2302  // Implementation of unsigned i64 to f64 following the algorithm in
2303  // __floatundidf in compiler_rt. This implementation has the advantage
2304  // of performing rounding correctly, both in the default rounding mode
2305  // and in all alternate rounding modes.
2306  // TODO: Generalize this for use with other types.
2307  if (Op0.getValueType() == MVT::i64 && DestVT == MVT::f64) {
2308    SDValue TwoP52 =
2309      DAG.getConstant(UINT64_C(0x4330000000000000), MVT::i64);
2310    SDValue TwoP84PlusTwoP52 =
2311      DAG.getConstantFP(BitsToDouble(UINT64_C(0x4530000000100000)), MVT::f64);
2312    SDValue TwoP84 =
2313      DAG.getConstant(UINT64_C(0x4530000000000000), MVT::i64);
2314
2315    SDValue Lo = DAG.getZeroExtendInReg(Op0, dl, MVT::i32);
2316    SDValue Hi = DAG.getNode(ISD::SRL, dl, MVT::i64, Op0,
2317                             DAG.getConstant(32, MVT::i64));
2318    SDValue LoOr = DAG.getNode(ISD::OR, dl, MVT::i64, Lo, TwoP52);
2319    SDValue HiOr = DAG.getNode(ISD::OR, dl, MVT::i64, Hi, TwoP84);
2320    SDValue LoFlt = DAG.getNode(ISD::BITCAST, dl, MVT::f64, LoOr);
2321    SDValue HiFlt = DAG.getNode(ISD::BITCAST, dl, MVT::f64, HiOr);
2322    SDValue HiSub = DAG.getNode(ISD::FSUB, dl, MVT::f64, HiFlt,
2323                                TwoP84PlusTwoP52);
2324    return DAG.getNode(ISD::FADD, dl, MVT::f64, LoFlt, HiSub);
2325  }
2326
2327  // Implementation of unsigned i64 to f32.
2328  // TODO: Generalize this for use with other types.
2329  if (Op0.getValueType() == MVT::i64 && DestVT == MVT::f32) {
2330    // For unsigned conversions, convert them to signed conversions using the
2331    // algorithm from the x86_64 __floatundidf in compiler_rt.
2332    if (!isSigned) {
2333      SDValue Fast = DAG.getNode(ISD::SINT_TO_FP, dl, MVT::f32, Op0);
2334
2335      SDValue ShiftConst =
2336          DAG.getConstant(1, TLI.getShiftAmountTy(Op0.getValueType()));
2337      SDValue Shr = DAG.getNode(ISD::SRL, dl, MVT::i64, Op0, ShiftConst);
2338      SDValue AndConst = DAG.getConstant(1, MVT::i64);
2339      SDValue And = DAG.getNode(ISD::AND, dl, MVT::i64, Op0, AndConst);
2340      SDValue Or = DAG.getNode(ISD::OR, dl, MVT::i64, And, Shr);
2341
2342      SDValue SignCvt = DAG.getNode(ISD::SINT_TO_FP, dl, MVT::f32, Or);
2343      SDValue Slow = DAG.getNode(ISD::FADD, dl, MVT::f32, SignCvt, SignCvt);
2344
2345      // TODO: This really should be implemented using a branch rather than a
2346      // select.  We happen to get lucky and machinesink does the right
2347      // thing most of the time.  This would be a good candidate for a
2348      //pseudo-op, or, even better, for whole-function isel.
2349      SDValue SignBitTest = DAG.getSetCC(dl, getSetCCResultType(MVT::i64),
2350        Op0, DAG.getConstant(0, MVT::i64), ISD::SETLT);
2351      return DAG.getSelect(dl, MVT::f32, SignBitTest, Slow, Fast);
2352    }
2353
2354    // Otherwise, implement the fully general conversion.
2355
2356    SDValue And = DAG.getNode(ISD::AND, dl, MVT::i64, Op0,
2357         DAG.getConstant(UINT64_C(0xfffffffffffff800), MVT::i64));
2358    SDValue Or = DAG.getNode(ISD::OR, dl, MVT::i64, And,
2359         DAG.getConstant(UINT64_C(0x800), MVT::i64));
2360    SDValue And2 = DAG.getNode(ISD::AND, dl, MVT::i64, Op0,
2361         DAG.getConstant(UINT64_C(0x7ff), MVT::i64));
2362    SDValue Ne = DAG.getSetCC(dl, getSetCCResultType(MVT::i64),
2363                   And2, DAG.getConstant(UINT64_C(0), MVT::i64), ISD::SETNE);
2364    SDValue Sel = DAG.getSelect(dl, MVT::i64, Ne, Or, Op0);
2365    SDValue Ge = DAG.getSetCC(dl, getSetCCResultType(MVT::i64),
2366                   Op0, DAG.getConstant(UINT64_C(0x0020000000000000), MVT::i64),
2367                   ISD::SETUGE);
2368    SDValue Sel2 = DAG.getSelect(dl, MVT::i64, Ge, Sel, Op0);
2369    EVT SHVT = TLI.getShiftAmountTy(Sel2.getValueType());
2370
2371    SDValue Sh = DAG.getNode(ISD::SRL, dl, MVT::i64, Sel2,
2372                             DAG.getConstant(32, SHVT));
2373    SDValue Trunc = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, Sh);
2374    SDValue Fcvt = DAG.getNode(ISD::UINT_TO_FP, dl, MVT::f64, Trunc);
2375    SDValue TwoP32 =
2376      DAG.getConstantFP(BitsToDouble(UINT64_C(0x41f0000000000000)), MVT::f64);
2377    SDValue Fmul = DAG.getNode(ISD::FMUL, dl, MVT::f64, TwoP32, Fcvt);
2378    SDValue Lo = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, Sel2);
2379    SDValue Fcvt2 = DAG.getNode(ISD::UINT_TO_FP, dl, MVT::f64, Lo);
2380    SDValue Fadd = DAG.getNode(ISD::FADD, dl, MVT::f64, Fmul, Fcvt2);
2381    return DAG.getNode(ISD::FP_ROUND, dl, MVT::f32, Fadd,
2382                       DAG.getIntPtrConstant(0));
2383  }
2384
2385  SDValue Tmp1 = DAG.getNode(ISD::SINT_TO_FP, dl, DestVT, Op0);
2386
2387  SDValue SignSet = DAG.getSetCC(dl, getSetCCResultType(Op0.getValueType()),
2388                                 Op0, DAG.getConstant(0, Op0.getValueType()),
2389                                 ISD::SETLT);
2390  SDValue Zero = DAG.getIntPtrConstant(0), Four = DAG.getIntPtrConstant(4);
2391  SDValue CstOffset = DAG.getSelect(dl, Zero.getValueType(),
2392                                    SignSet, Four, Zero);
2393
2394  // If the sign bit of the integer is set, the large number will be treated
2395  // as a negative number.  To counteract this, the dynamic code adds an
2396  // offset depending on the data type.
2397  uint64_t FF;
2398  switch (Op0.getSimpleValueType().SimpleTy) {
2399  default: llvm_unreachable("Unsupported integer type!");
2400  case MVT::i8 : FF = 0x43800000ULL; break;  // 2^8  (as a float)
2401  case MVT::i16: FF = 0x47800000ULL; break;  // 2^16 (as a float)
2402  case MVT::i32: FF = 0x4F800000ULL; break;  // 2^32 (as a float)
2403  case MVT::i64: FF = 0x5F800000ULL; break;  // 2^64 (as a float)
2404  }
2405  if (TLI.isLittleEndian()) FF <<= 32;
2406  Constant *FudgeFactor = ConstantInt::get(
2407                                       Type::getInt64Ty(*DAG.getContext()), FF);
2408
2409  SDValue CPIdx = DAG.getConstantPool(FudgeFactor, TLI.getPointerTy());
2410  unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
2411  CPIdx = DAG.getNode(ISD::ADD, dl, CPIdx.getValueType(), CPIdx, CstOffset);
2412  Alignment = std::min(Alignment, 4u);
2413  SDValue FudgeInReg;
2414  if (DestVT == MVT::f32)
2415    FudgeInReg = DAG.getLoad(MVT::f32, dl, DAG.getEntryNode(), CPIdx,
2416                             MachinePointerInfo::getConstantPool(),
2417                             false, false, false, Alignment);
2418  else {
2419    SDValue Load = DAG.getExtLoad(ISD::EXTLOAD, dl, DestVT,
2420                                  DAG.getEntryNode(), CPIdx,
2421                                  MachinePointerInfo::getConstantPool(),
2422                                  MVT::f32, false, false, Alignment);
2423    HandleSDNode Handle(Load);
2424    LegalizeOp(Load.getNode());
2425    FudgeInReg = Handle.getValue();
2426  }
2427
2428  return DAG.getNode(ISD::FADD, dl, DestVT, Tmp1, FudgeInReg);
2429}
2430
2431/// PromoteLegalINT_TO_FP - This function is responsible for legalizing a
2432/// *INT_TO_FP operation of the specified operand when the target requests that
2433/// we promote it.  At this point, we know that the result and operand types are
2434/// legal for the target, and that there is a legal UINT_TO_FP or SINT_TO_FP
2435/// operation that takes a larger input.
2436SDValue SelectionDAGLegalize::PromoteLegalINT_TO_FP(SDValue LegalOp,
2437                                                    EVT DestVT,
2438                                                    bool isSigned,
2439                                                    SDLoc dl) {
2440  // First step, figure out the appropriate *INT_TO_FP operation to use.
2441  EVT NewInTy = LegalOp.getValueType();
2442
2443  unsigned OpToUse = 0;
2444
2445  // Scan for the appropriate larger type to use.
2446  while (1) {
2447    NewInTy = (MVT::SimpleValueType)(NewInTy.getSimpleVT().SimpleTy+1);
2448    assert(NewInTy.isInteger() && "Ran out of possibilities!");
2449
2450    // If the target supports SINT_TO_FP of this type, use it.
2451    if (TLI.isOperationLegalOrCustom(ISD::SINT_TO_FP, NewInTy)) {
2452      OpToUse = ISD::SINT_TO_FP;
2453      break;
2454    }
2455    if (isSigned) continue;
2456
2457    // If the target supports UINT_TO_FP of this type, use it.
2458    if (TLI.isOperationLegalOrCustom(ISD::UINT_TO_FP, NewInTy)) {
2459      OpToUse = ISD::UINT_TO_FP;
2460      break;
2461    }
2462
2463    // Otherwise, try a larger type.
2464  }
2465
2466  // Okay, we found the operation and type to use.  Zero extend our input to the
2467  // desired type then run the operation on it.
2468  return DAG.getNode(OpToUse, dl, DestVT,
2469                     DAG.getNode(isSigned ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND,
2470                                 dl, NewInTy, LegalOp));
2471}
2472
2473/// PromoteLegalFP_TO_INT - This function is responsible for legalizing a
2474/// FP_TO_*INT operation of the specified operand when the target requests that
2475/// we promote it.  At this point, we know that the result and operand types are
2476/// legal for the target, and that there is a legal FP_TO_UINT or FP_TO_SINT
2477/// operation that returns a larger result.
2478SDValue SelectionDAGLegalize::PromoteLegalFP_TO_INT(SDValue LegalOp,
2479                                                    EVT DestVT,
2480                                                    bool isSigned,
2481                                                    SDLoc dl) {
2482  // First step, figure out the appropriate FP_TO*INT operation to use.
2483  EVT NewOutTy = DestVT;
2484
2485  unsigned OpToUse = 0;
2486
2487  // Scan for the appropriate larger type to use.
2488  while (1) {
2489    NewOutTy = (MVT::SimpleValueType)(NewOutTy.getSimpleVT().SimpleTy+1);
2490    assert(NewOutTy.isInteger() && "Ran out of possibilities!");
2491
2492    if (TLI.isOperationLegalOrCustom(ISD::FP_TO_SINT, NewOutTy)) {
2493      OpToUse = ISD::FP_TO_SINT;
2494      break;
2495    }
2496
2497    if (TLI.isOperationLegalOrCustom(ISD::FP_TO_UINT, NewOutTy)) {
2498      OpToUse = ISD::FP_TO_UINT;
2499      break;
2500    }
2501
2502    // Otherwise, try a larger type.
2503  }
2504
2505
2506  // Okay, we found the operation and type to use.
2507  SDValue Operation = DAG.getNode(OpToUse, dl, NewOutTy, LegalOp);
2508
2509  // Truncate the result of the extended FP_TO_*INT operation to the desired
2510  // size.
2511  return DAG.getNode(ISD::TRUNCATE, dl, DestVT, Operation);
2512}
2513
2514/// ExpandBSWAP - Open code the operations for BSWAP of the specified operation.
2515///
2516SDValue SelectionDAGLegalize::ExpandBSWAP(SDValue Op, SDLoc dl) {
2517  EVT VT = Op.getValueType();
2518  EVT SHVT = TLI.getShiftAmountTy(VT);
2519  SDValue Tmp1, Tmp2, Tmp3, Tmp4, Tmp5, Tmp6, Tmp7, Tmp8;
2520  switch (VT.getSimpleVT().SimpleTy) {
2521  default: llvm_unreachable("Unhandled Expand type in BSWAP!");
2522  case MVT::i16:
2523    Tmp2 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, SHVT));
2524    Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, SHVT));
2525    return DAG.getNode(ISD::OR, dl, VT, Tmp1, Tmp2);
2526  case MVT::i32:
2527    Tmp4 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(24, SHVT));
2528    Tmp3 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, SHVT));
2529    Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, SHVT));
2530    Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(24, SHVT));
2531    Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp3, DAG.getConstant(0xFF0000, VT));
2532    Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2, DAG.getConstant(0xFF00, VT));
2533    Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp3);
2534    Tmp2 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp1);
2535    return DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp2);
2536  case MVT::i64:
2537    Tmp8 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(56, SHVT));
2538    Tmp7 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(40, SHVT));
2539    Tmp6 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(24, SHVT));
2540    Tmp5 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, SHVT));
2541    Tmp4 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, SHVT));
2542    Tmp3 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(24, SHVT));
2543    Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(40, SHVT));
2544    Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(56, SHVT));
2545    Tmp7 = DAG.getNode(ISD::AND, dl, VT, Tmp7, DAG.getConstant(255ULL<<48, VT));
2546    Tmp6 = DAG.getNode(ISD::AND, dl, VT, Tmp6, DAG.getConstant(255ULL<<40, VT));
2547    Tmp5 = DAG.getNode(ISD::AND, dl, VT, Tmp5, DAG.getConstant(255ULL<<32, VT));
2548    Tmp4 = DAG.getNode(ISD::AND, dl, VT, Tmp4, DAG.getConstant(255ULL<<24, VT));
2549    Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp3, DAG.getConstant(255ULL<<16, VT));
2550    Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2, DAG.getConstant(255ULL<<8 , VT));
2551    Tmp8 = DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp7);
2552    Tmp6 = DAG.getNode(ISD::OR, dl, VT, Tmp6, Tmp5);
2553    Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp3);
2554    Tmp2 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp1);
2555    Tmp8 = DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp6);
2556    Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp2);
2557    return DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp4);
2558  }
2559}
2560
2561/// ExpandBitCount - Expand the specified bitcount instruction into operations.
2562///
2563SDValue SelectionDAGLegalize::ExpandBitCount(unsigned Opc, SDValue Op,
2564                                             SDLoc dl) {
2565  switch (Opc) {
2566  default: llvm_unreachable("Cannot expand this yet!");
2567  case ISD::CTPOP: {
2568    EVT VT = Op.getValueType();
2569    EVT ShVT = TLI.getShiftAmountTy(VT);
2570    unsigned Len = VT.getSizeInBits();
2571
2572    assert(VT.isInteger() && Len <= 128 && Len % 8 == 0 &&
2573           "CTPOP not implemented for this type.");
2574
2575    // This is the "best" algorithm from
2576    // http://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetParallel
2577
2578    SDValue Mask55 = DAG.getConstant(APInt::getSplat(Len, APInt(8, 0x55)), VT);
2579    SDValue Mask33 = DAG.getConstant(APInt::getSplat(Len, APInt(8, 0x33)), VT);
2580    SDValue Mask0F = DAG.getConstant(APInt::getSplat(Len, APInt(8, 0x0F)), VT);
2581    SDValue Mask01 = DAG.getConstant(APInt::getSplat(Len, APInt(8, 0x01)), VT);
2582
2583    // v = v - ((v >> 1) & 0x55555555...)
2584    Op = DAG.getNode(ISD::SUB, dl, VT, Op,
2585                     DAG.getNode(ISD::AND, dl, VT,
2586                                 DAG.getNode(ISD::SRL, dl, VT, Op,
2587                                             DAG.getConstant(1, ShVT)),
2588                                 Mask55));
2589    // v = (v & 0x33333333...) + ((v >> 2) & 0x33333333...)
2590    Op = DAG.getNode(ISD::ADD, dl, VT,
2591                     DAG.getNode(ISD::AND, dl, VT, Op, Mask33),
2592                     DAG.getNode(ISD::AND, dl, VT,
2593                                 DAG.getNode(ISD::SRL, dl, VT, Op,
2594                                             DAG.getConstant(2, ShVT)),
2595                                 Mask33));
2596    // v = (v + (v >> 4)) & 0x0F0F0F0F...
2597    Op = DAG.getNode(ISD::AND, dl, VT,
2598                     DAG.getNode(ISD::ADD, dl, VT, Op,
2599                                 DAG.getNode(ISD::SRL, dl, VT, Op,
2600                                             DAG.getConstant(4, ShVT))),
2601                     Mask0F);
2602    // v = (v * 0x01010101...) >> (Len - 8)
2603    Op = DAG.getNode(ISD::SRL, dl, VT,
2604                     DAG.getNode(ISD::MUL, dl, VT, Op, Mask01),
2605                     DAG.getConstant(Len - 8, ShVT));
2606
2607    return Op;
2608  }
2609  case ISD::CTLZ_ZERO_UNDEF:
2610    // This trivially expands to CTLZ.
2611    return DAG.getNode(ISD::CTLZ, dl, Op.getValueType(), Op);
2612  case ISD::CTLZ: {
2613    // for now, we do this:
2614    // x = x | (x >> 1);
2615    // x = x | (x >> 2);
2616    // ...
2617    // x = x | (x >>16);
2618    // x = x | (x >>32); // for 64-bit input
2619    // return popcount(~x);
2620    //
2621    // but see also: http://www.hackersdelight.org/HDcode/nlz.cc
2622    EVT VT = Op.getValueType();
2623    EVT ShVT = TLI.getShiftAmountTy(VT);
2624    unsigned len = VT.getSizeInBits();
2625    for (unsigned i = 0; (1U << i) <= (len / 2); ++i) {
2626      SDValue Tmp3 = DAG.getConstant(1ULL << i, ShVT);
2627      Op = DAG.getNode(ISD::OR, dl, VT, Op,
2628                       DAG.getNode(ISD::SRL, dl, VT, Op, Tmp3));
2629    }
2630    Op = DAG.getNOT(dl, Op, VT);
2631    return DAG.getNode(ISD::CTPOP, dl, VT, Op);
2632  }
2633  case ISD::CTTZ_ZERO_UNDEF:
2634    // This trivially expands to CTTZ.
2635    return DAG.getNode(ISD::CTTZ, dl, Op.getValueType(), Op);
2636  case ISD::CTTZ: {
2637    // for now, we use: { return popcount(~x & (x - 1)); }
2638    // unless the target has ctlz but not ctpop, in which case we use:
2639    // { return 32 - nlz(~x & (x-1)); }
2640    // see also http://www.hackersdelight.org/HDcode/ntz.cc
2641    EVT VT = Op.getValueType();
2642    SDValue Tmp3 = DAG.getNode(ISD::AND, dl, VT,
2643                               DAG.getNOT(dl, Op, VT),
2644                               DAG.getNode(ISD::SUB, dl, VT, Op,
2645                                           DAG.getConstant(1, VT)));
2646    // If ISD::CTLZ is legal and CTPOP isn't, then do that instead.
2647    if (!TLI.isOperationLegalOrCustom(ISD::CTPOP, VT) &&
2648        TLI.isOperationLegalOrCustom(ISD::CTLZ, VT))
2649      return DAG.getNode(ISD::SUB, dl, VT,
2650                         DAG.getConstant(VT.getSizeInBits(), VT),
2651                         DAG.getNode(ISD::CTLZ, dl, VT, Tmp3));
2652    return DAG.getNode(ISD::CTPOP, dl, VT, Tmp3);
2653  }
2654  }
2655}
2656
2657std::pair <SDValue, SDValue> SelectionDAGLegalize::ExpandAtomic(SDNode *Node) {
2658  unsigned Opc = Node->getOpcode();
2659  MVT VT = cast<AtomicSDNode>(Node)->getMemoryVT().getSimpleVT();
2660  RTLIB::Libcall LC;
2661
2662  switch (Opc) {
2663  default:
2664    llvm_unreachable("Unhandled atomic intrinsic Expand!");
2665  case ISD::ATOMIC_SWAP:
2666    switch (VT.SimpleTy) {
2667    default: llvm_unreachable("Unexpected value type for atomic!");
2668    case MVT::i8:  LC = RTLIB::SYNC_LOCK_TEST_AND_SET_1; break;
2669    case MVT::i16: LC = RTLIB::SYNC_LOCK_TEST_AND_SET_2; break;
2670    case MVT::i32: LC = RTLIB::SYNC_LOCK_TEST_AND_SET_4; break;
2671    case MVT::i64: LC = RTLIB::SYNC_LOCK_TEST_AND_SET_8; break;
2672    case MVT::i128:LC = RTLIB::SYNC_LOCK_TEST_AND_SET_16;break;
2673    }
2674    break;
2675  case ISD::ATOMIC_CMP_SWAP:
2676    switch (VT.SimpleTy) {
2677    default: llvm_unreachable("Unexpected value type for atomic!");
2678    case MVT::i8:  LC = RTLIB::SYNC_VAL_COMPARE_AND_SWAP_1; break;
2679    case MVT::i16: LC = RTLIB::SYNC_VAL_COMPARE_AND_SWAP_2; break;
2680    case MVT::i32: LC = RTLIB::SYNC_VAL_COMPARE_AND_SWAP_4; break;
2681    case MVT::i64: LC = RTLIB::SYNC_VAL_COMPARE_AND_SWAP_8; break;
2682    case MVT::i128:LC = RTLIB::SYNC_VAL_COMPARE_AND_SWAP_16;break;
2683    }
2684    break;
2685  case ISD::ATOMIC_LOAD_ADD:
2686    switch (VT.SimpleTy) {
2687    default: llvm_unreachable("Unexpected value type for atomic!");
2688    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_ADD_1; break;
2689    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_ADD_2; break;
2690    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_ADD_4; break;
2691    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_ADD_8; break;
2692    case MVT::i128:LC = RTLIB::SYNC_FETCH_AND_ADD_16;break;
2693    }
2694    break;
2695  case ISD::ATOMIC_LOAD_SUB:
2696    switch (VT.SimpleTy) {
2697    default: llvm_unreachable("Unexpected value type for atomic!");
2698    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_SUB_1; break;
2699    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_SUB_2; break;
2700    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_SUB_4; break;
2701    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_SUB_8; break;
2702    case MVT::i128:LC = RTLIB::SYNC_FETCH_AND_SUB_16;break;
2703    }
2704    break;
2705  case ISD::ATOMIC_LOAD_AND:
2706    switch (VT.SimpleTy) {
2707    default: llvm_unreachable("Unexpected value type for atomic!");
2708    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_AND_1; break;
2709    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_AND_2; break;
2710    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_AND_4; break;
2711    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_AND_8; break;
2712    case MVT::i128:LC = RTLIB::SYNC_FETCH_AND_AND_16;break;
2713    }
2714    break;
2715  case ISD::ATOMIC_LOAD_OR:
2716    switch (VT.SimpleTy) {
2717    default: llvm_unreachable("Unexpected value type for atomic!");
2718    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_OR_1; break;
2719    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_OR_2; break;
2720    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_OR_4; break;
2721    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_OR_8; break;
2722    case MVT::i128:LC = RTLIB::SYNC_FETCH_AND_OR_16;break;
2723    }
2724    break;
2725  case ISD::ATOMIC_LOAD_XOR:
2726    switch (VT.SimpleTy) {
2727    default: llvm_unreachable("Unexpected value type for atomic!");
2728    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_XOR_1; break;
2729    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_XOR_2; break;
2730    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_XOR_4; break;
2731    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_XOR_8; break;
2732    case MVT::i128:LC = RTLIB::SYNC_FETCH_AND_XOR_16;break;
2733    }
2734    break;
2735  case ISD::ATOMIC_LOAD_NAND:
2736    switch (VT.SimpleTy) {
2737    default: llvm_unreachable("Unexpected value type for atomic!");
2738    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_NAND_1; break;
2739    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_NAND_2; break;
2740    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_NAND_4; break;
2741    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_NAND_8; break;
2742    case MVT::i128:LC = RTLIB::SYNC_FETCH_AND_NAND_16;break;
2743    }
2744    break;
2745  case ISD::ATOMIC_LOAD_MAX:
2746    switch (VT.SimpleTy) {
2747    default: llvm_unreachable("Unexpected value type for atomic!");
2748    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_MAX_1; break;
2749    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_MAX_2; break;
2750    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_MAX_4; break;
2751    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_MAX_8; break;
2752    case MVT::i128:LC = RTLIB::SYNC_FETCH_AND_MAX_16;break;
2753    }
2754    break;
2755  case ISD::ATOMIC_LOAD_UMAX:
2756    switch (VT.SimpleTy) {
2757    default: llvm_unreachable("Unexpected value type for atomic!");
2758    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_UMAX_1; break;
2759    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_UMAX_2; break;
2760    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_UMAX_4; break;
2761    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_UMAX_8; break;
2762    case MVT::i128:LC = RTLIB::SYNC_FETCH_AND_UMAX_16;break;
2763    }
2764    break;
2765  case ISD::ATOMIC_LOAD_MIN:
2766    switch (VT.SimpleTy) {
2767    default: llvm_unreachable("Unexpected value type for atomic!");
2768    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_MIN_1; break;
2769    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_MIN_2; break;
2770    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_MIN_4; break;
2771    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_MIN_8; break;
2772    case MVT::i128:LC = RTLIB::SYNC_FETCH_AND_MIN_16;break;
2773    }
2774    break;
2775  case ISD::ATOMIC_LOAD_UMIN:
2776    switch (VT.SimpleTy) {
2777    default: llvm_unreachable("Unexpected value type for atomic!");
2778    case MVT::i8:  LC = RTLIB::SYNC_FETCH_AND_UMIN_1; break;
2779    case MVT::i16: LC = RTLIB::SYNC_FETCH_AND_UMIN_2; break;
2780    case MVT::i32: LC = RTLIB::SYNC_FETCH_AND_UMIN_4; break;
2781    case MVT::i64: LC = RTLIB::SYNC_FETCH_AND_UMIN_8; break;
2782    case MVT::i128:LC = RTLIB::SYNC_FETCH_AND_UMIN_16;break;
2783    }
2784    break;
2785  }
2786
2787  return ExpandChainLibCall(LC, Node, false);
2788}
2789
2790void SelectionDAGLegalize::ExpandNode(SDNode *Node) {
2791  SmallVector<SDValue, 8> Results;
2792  SDLoc dl(Node);
2793  SDValue Tmp1, Tmp2, Tmp3, Tmp4;
2794  switch (Node->getOpcode()) {
2795  case ISD::CTPOP:
2796  case ISD::CTLZ:
2797  case ISD::CTLZ_ZERO_UNDEF:
2798  case ISD::CTTZ:
2799  case ISD::CTTZ_ZERO_UNDEF:
2800    Tmp1 = ExpandBitCount(Node->getOpcode(), Node->getOperand(0), dl);
2801    Results.push_back(Tmp1);
2802    break;
2803  case ISD::BSWAP:
2804    Results.push_back(ExpandBSWAP(Node->getOperand(0), dl));
2805    break;
2806  case ISD::FRAMEADDR:
2807  case ISD::RETURNADDR:
2808  case ISD::FRAME_TO_ARGS_OFFSET:
2809    Results.push_back(DAG.getConstant(0, Node->getValueType(0)));
2810    break;
2811  case ISD::FLT_ROUNDS_:
2812    Results.push_back(DAG.getConstant(1, Node->getValueType(0)));
2813    break;
2814  case ISD::EH_RETURN:
2815  case ISD::EH_LABEL:
2816  case ISD::PREFETCH:
2817  case ISD::VAEND:
2818  case ISD::EH_SJLJ_LONGJMP:
2819    // If the target didn't expand these, there's nothing to do, so just
2820    // preserve the chain and be done.
2821    Results.push_back(Node->getOperand(0));
2822    break;
2823  case ISD::EH_SJLJ_SETJMP:
2824    // If the target didn't expand this, just return 'zero' and preserve the
2825    // chain.
2826    Results.push_back(DAG.getConstant(0, MVT::i32));
2827    Results.push_back(Node->getOperand(0));
2828    break;
2829  case ISD::ATOMIC_FENCE: {
2830    // If the target didn't lower this, lower it to '__sync_synchronize()' call
2831    // FIXME: handle "fence singlethread" more efficiently.
2832    TargetLowering::ArgListTy Args;
2833    TargetLowering::
2834    CallLoweringInfo CLI(Node->getOperand(0),
2835                         Type::getVoidTy(*DAG.getContext()),
2836                      false, false, false, false, 0, CallingConv::C,
2837                      /*isTailCall=*/false,
2838                      /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
2839                      DAG.getExternalSymbol("__sync_synchronize",
2840                                            TLI.getPointerTy()),
2841                      Args, DAG, dl);
2842    std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
2843
2844    Results.push_back(CallResult.second);
2845    break;
2846  }
2847  case ISD::ATOMIC_LOAD: {
2848    // There is no libcall for atomic load; fake it with ATOMIC_CMP_SWAP.
2849    SDValue Zero = DAG.getConstant(0, Node->getValueType(0));
2850    SDValue Swap = DAG.getAtomic(ISD::ATOMIC_CMP_SWAP, dl,
2851                                 cast<AtomicSDNode>(Node)->getMemoryVT(),
2852                                 Node->getOperand(0),
2853                                 Node->getOperand(1), Zero, Zero,
2854                                 cast<AtomicSDNode>(Node)->getMemOperand(),
2855                                 cast<AtomicSDNode>(Node)->getOrdering(),
2856                                 cast<AtomicSDNode>(Node)->getSynchScope());
2857    Results.push_back(Swap.getValue(0));
2858    Results.push_back(Swap.getValue(1));
2859    break;
2860  }
2861  case ISD::ATOMIC_STORE: {
2862    // There is no libcall for atomic store; fake it with ATOMIC_SWAP.
2863    SDValue Swap = DAG.getAtomic(ISD::ATOMIC_SWAP, dl,
2864                                 cast<AtomicSDNode>(Node)->getMemoryVT(),
2865                                 Node->getOperand(0),
2866                                 Node->getOperand(1), Node->getOperand(2),
2867                                 cast<AtomicSDNode>(Node)->getMemOperand(),
2868                                 cast<AtomicSDNode>(Node)->getOrdering(),
2869                                 cast<AtomicSDNode>(Node)->getSynchScope());
2870    Results.push_back(Swap.getValue(1));
2871    break;
2872  }
2873  // By default, atomic intrinsics are marked Legal and lowered. Targets
2874  // which don't support them directly, however, may want libcalls, in which
2875  // case they mark them Expand, and we get here.
2876  case ISD::ATOMIC_SWAP:
2877  case ISD::ATOMIC_LOAD_ADD:
2878  case ISD::ATOMIC_LOAD_SUB:
2879  case ISD::ATOMIC_LOAD_AND:
2880  case ISD::ATOMIC_LOAD_OR:
2881  case ISD::ATOMIC_LOAD_XOR:
2882  case ISD::ATOMIC_LOAD_NAND:
2883  case ISD::ATOMIC_LOAD_MIN:
2884  case ISD::ATOMIC_LOAD_MAX:
2885  case ISD::ATOMIC_LOAD_UMIN:
2886  case ISD::ATOMIC_LOAD_UMAX:
2887  case ISD::ATOMIC_CMP_SWAP: {
2888    std::pair<SDValue, SDValue> Tmp = ExpandAtomic(Node);
2889    Results.push_back(Tmp.first);
2890    Results.push_back(Tmp.second);
2891    break;
2892  }
2893  case ISD::DYNAMIC_STACKALLOC:
2894    ExpandDYNAMIC_STACKALLOC(Node, Results);
2895    break;
2896  case ISD::MERGE_VALUES:
2897    for (unsigned i = 0; i < Node->getNumValues(); i++)
2898      Results.push_back(Node->getOperand(i));
2899    break;
2900  case ISD::UNDEF: {
2901    EVT VT = Node->getValueType(0);
2902    if (VT.isInteger())
2903      Results.push_back(DAG.getConstant(0, VT));
2904    else {
2905      assert(VT.isFloatingPoint() && "Unknown value type!");
2906      Results.push_back(DAG.getConstantFP(0, VT));
2907    }
2908    break;
2909  }
2910  case ISD::TRAP: {
2911    // If this operation is not supported, lower it to 'abort()' call
2912    TargetLowering::ArgListTy Args;
2913    TargetLowering::
2914    CallLoweringInfo CLI(Node->getOperand(0),
2915                         Type::getVoidTy(*DAG.getContext()),
2916                      false, false, false, false, 0, CallingConv::C,
2917                      /*isTailCall=*/false,
2918                      /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
2919                      DAG.getExternalSymbol("abort", TLI.getPointerTy()),
2920                      Args, DAG, dl);
2921    std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
2922
2923    Results.push_back(CallResult.second);
2924    break;
2925  }
2926  case ISD::FP_ROUND:
2927  case ISD::BITCAST:
2928    Tmp1 = EmitStackConvert(Node->getOperand(0), Node->getValueType(0),
2929                            Node->getValueType(0), dl);
2930    Results.push_back(Tmp1);
2931    break;
2932  case ISD::FP_EXTEND:
2933    Tmp1 = EmitStackConvert(Node->getOperand(0),
2934                            Node->getOperand(0).getValueType(),
2935                            Node->getValueType(0), dl);
2936    Results.push_back(Tmp1);
2937    break;
2938  case ISD::SIGN_EXTEND_INREG: {
2939    // NOTE: we could fall back on load/store here too for targets without
2940    // SAR.  However, it is doubtful that any exist.
2941    EVT ExtraVT = cast<VTSDNode>(Node->getOperand(1))->getVT();
2942    EVT VT = Node->getValueType(0);
2943    EVT ShiftAmountTy = TLI.getShiftAmountTy(VT);
2944    if (VT.isVector())
2945      ShiftAmountTy = VT;
2946    unsigned BitsDiff = VT.getScalarType().getSizeInBits() -
2947                        ExtraVT.getScalarType().getSizeInBits();
2948    SDValue ShiftCst = DAG.getConstant(BitsDiff, ShiftAmountTy);
2949    Tmp1 = DAG.getNode(ISD::SHL, dl, Node->getValueType(0),
2950                       Node->getOperand(0), ShiftCst);
2951    Tmp1 = DAG.getNode(ISD::SRA, dl, Node->getValueType(0), Tmp1, ShiftCst);
2952    Results.push_back(Tmp1);
2953    break;
2954  }
2955  case ISD::FP_ROUND_INREG: {
2956    // The only way we can lower this is to turn it into a TRUNCSTORE,
2957    // EXTLOAD pair, targeting a temporary location (a stack slot).
2958
2959    // NOTE: there is a choice here between constantly creating new stack
2960    // slots and always reusing the same one.  We currently always create
2961    // new ones, as reuse may inhibit scheduling.
2962    EVT ExtraVT = cast<VTSDNode>(Node->getOperand(1))->getVT();
2963    Tmp1 = EmitStackConvert(Node->getOperand(0), ExtraVT,
2964                            Node->getValueType(0), dl);
2965    Results.push_back(Tmp1);
2966    break;
2967  }
2968  case ISD::SINT_TO_FP:
2969  case ISD::UINT_TO_FP:
2970    Tmp1 = ExpandLegalINT_TO_FP(Node->getOpcode() == ISD::SINT_TO_FP,
2971                                Node->getOperand(0), Node->getValueType(0), dl);
2972    Results.push_back(Tmp1);
2973    break;
2974  case ISD::FP_TO_UINT: {
2975    SDValue True, False;
2976    EVT VT =  Node->getOperand(0).getValueType();
2977    EVT NVT = Node->getValueType(0);
2978    APFloat apf(DAG.EVTToAPFloatSemantics(VT),
2979                APInt::getNullValue(VT.getSizeInBits()));
2980    APInt x = APInt::getSignBit(NVT.getSizeInBits());
2981    (void)apf.convertFromAPInt(x, false, APFloat::rmNearestTiesToEven);
2982    Tmp1 = DAG.getConstantFP(apf, VT);
2983    Tmp2 = DAG.getSetCC(dl, getSetCCResultType(VT),
2984                        Node->getOperand(0),
2985                        Tmp1, ISD::SETLT);
2986    True = DAG.getNode(ISD::FP_TO_SINT, dl, NVT, Node->getOperand(0));
2987    False = DAG.getNode(ISD::FP_TO_SINT, dl, NVT,
2988                        DAG.getNode(ISD::FSUB, dl, VT,
2989                                    Node->getOperand(0), Tmp1));
2990    False = DAG.getNode(ISD::XOR, dl, NVT, False,
2991                        DAG.getConstant(x, NVT));
2992    Tmp1 = DAG.getSelect(dl, NVT, Tmp2, True, False);
2993    Results.push_back(Tmp1);
2994    break;
2995  }
2996  case ISD::VAARG: {
2997    const Value *V = cast<SrcValueSDNode>(Node->getOperand(2))->getValue();
2998    EVT VT = Node->getValueType(0);
2999    Tmp1 = Node->getOperand(0);
3000    Tmp2 = Node->getOperand(1);
3001    unsigned Align = Node->getConstantOperandVal(3);
3002
3003    SDValue VAListLoad = DAG.getLoad(TLI.getPointerTy(), dl, Tmp1, Tmp2,
3004                                     MachinePointerInfo(V),
3005                                     false, false, false, 0);
3006    SDValue VAList = VAListLoad;
3007
3008    if (Align > TLI.getMinStackArgumentAlignment()) {
3009      assert(((Align & (Align-1)) == 0) && "Expected Align to be a power of 2");
3010
3011      VAList = DAG.getNode(ISD::ADD, dl, VAList.getValueType(), VAList,
3012                           DAG.getConstant(Align - 1,
3013                                           VAList.getValueType()));
3014
3015      VAList = DAG.getNode(ISD::AND, dl, VAList.getValueType(), VAList,
3016                           DAG.getConstant(-(int64_t)Align,
3017                                           VAList.getValueType()));
3018    }
3019
3020    // Increment the pointer, VAList, to the next vaarg
3021    Tmp3 = DAG.getNode(ISD::ADD, dl, VAList.getValueType(), VAList,
3022                       DAG.getConstant(TLI.getDataLayout()->
3023                          getTypeAllocSize(VT.getTypeForEVT(*DAG.getContext())),
3024                                       VAList.getValueType()));
3025    // Store the incremented VAList to the legalized pointer
3026    Tmp3 = DAG.getStore(VAListLoad.getValue(1), dl, Tmp3, Tmp2,
3027                        MachinePointerInfo(V), false, false, 0);
3028    // Load the actual argument out of the pointer VAList
3029    Results.push_back(DAG.getLoad(VT, dl, Tmp3, VAList, MachinePointerInfo(),
3030                                  false, false, false, 0));
3031    Results.push_back(Results[0].getValue(1));
3032    break;
3033  }
3034  case ISD::VACOPY: {
3035    // This defaults to loading a pointer from the input and storing it to the
3036    // output, returning the chain.
3037    const Value *VD = cast<SrcValueSDNode>(Node->getOperand(3))->getValue();
3038    const Value *VS = cast<SrcValueSDNode>(Node->getOperand(4))->getValue();
3039    Tmp1 = DAG.getLoad(TLI.getPointerTy(), dl, Node->getOperand(0),
3040                       Node->getOperand(2), MachinePointerInfo(VS),
3041                       false, false, false, 0);
3042    Tmp1 = DAG.getStore(Tmp1.getValue(1), dl, Tmp1, Node->getOperand(1),
3043                        MachinePointerInfo(VD), false, false, 0);
3044    Results.push_back(Tmp1);
3045    break;
3046  }
3047  case ISD::EXTRACT_VECTOR_ELT:
3048    if (Node->getOperand(0).getValueType().getVectorNumElements() == 1)
3049      // This must be an access of the only element.  Return it.
3050      Tmp1 = DAG.getNode(ISD::BITCAST, dl, Node->getValueType(0),
3051                         Node->getOperand(0));
3052    else
3053      Tmp1 = ExpandExtractFromVectorThroughStack(SDValue(Node, 0));
3054    Results.push_back(Tmp1);
3055    break;
3056  case ISD::EXTRACT_SUBVECTOR:
3057    Results.push_back(ExpandExtractFromVectorThroughStack(SDValue(Node, 0)));
3058    break;
3059  case ISD::INSERT_SUBVECTOR:
3060    Results.push_back(ExpandInsertToVectorThroughStack(SDValue(Node, 0)));
3061    break;
3062  case ISD::CONCAT_VECTORS: {
3063    Results.push_back(ExpandVectorBuildThroughStack(Node));
3064    break;
3065  }
3066  case ISD::SCALAR_TO_VECTOR:
3067    Results.push_back(ExpandSCALAR_TO_VECTOR(Node));
3068    break;
3069  case ISD::INSERT_VECTOR_ELT:
3070    Results.push_back(ExpandINSERT_VECTOR_ELT(Node->getOperand(0),
3071                                              Node->getOperand(1),
3072                                              Node->getOperand(2), dl));
3073    break;
3074  case ISD::VECTOR_SHUFFLE: {
3075    SmallVector<int, 32> NewMask;
3076    ArrayRef<int> Mask = cast<ShuffleVectorSDNode>(Node)->getMask();
3077
3078    EVT VT = Node->getValueType(0);
3079    EVT EltVT = VT.getVectorElementType();
3080    SDValue Op0 = Node->getOperand(0);
3081    SDValue Op1 = Node->getOperand(1);
3082    if (!TLI.isTypeLegal(EltVT)) {
3083
3084      EVT NewEltVT = TLI.getTypeToTransformTo(*DAG.getContext(), EltVT);
3085
3086      // BUILD_VECTOR operands are allowed to be wider than the element type.
3087      // But if NewEltVT is smaller that EltVT the BUILD_VECTOR does not accept it
3088      if (NewEltVT.bitsLT(EltVT)) {
3089
3090        // Convert shuffle node.
3091        // If original node was v4i64 and the new EltVT is i32,
3092        // cast operands to v8i32 and re-build the mask.
3093
3094        // Calculate new VT, the size of the new VT should be equal to original.
3095        EVT NewVT = EVT::getVectorVT(*DAG.getContext(), NewEltVT,
3096                                      VT.getSizeInBits()/NewEltVT.getSizeInBits());
3097        assert(NewVT.bitsEq(VT));
3098
3099        // cast operands to new VT
3100        Op0 = DAG.getNode(ISD::BITCAST, dl, NewVT, Op0);
3101        Op1 = DAG.getNode(ISD::BITCAST, dl, NewVT, Op1);
3102
3103        // Convert the shuffle mask
3104        unsigned int factor = NewVT.getVectorNumElements()/VT.getVectorNumElements();
3105
3106        // EltVT gets smaller
3107        assert(factor > 0);
3108
3109        for (unsigned i = 0; i < VT.getVectorNumElements(); ++i) {
3110          if (Mask[i] < 0) {
3111            for (unsigned fi = 0; fi < factor; ++fi)
3112              NewMask.push_back(Mask[i]);
3113          }
3114          else {
3115            for (unsigned fi = 0; fi < factor; ++fi)
3116              NewMask.push_back(Mask[i]*factor+fi);
3117          }
3118        }
3119        Mask = NewMask;
3120        VT = NewVT;
3121      }
3122      EltVT = NewEltVT;
3123    }
3124    unsigned NumElems = VT.getVectorNumElements();
3125    SmallVector<SDValue, 16> Ops;
3126    for (unsigned i = 0; i != NumElems; ++i) {
3127      if (Mask[i] < 0) {
3128        Ops.push_back(DAG.getUNDEF(EltVT));
3129        continue;
3130      }
3131      unsigned Idx = Mask[i];
3132      if (Idx < NumElems)
3133        Ops.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, EltVT,
3134                                  Op0,
3135                                  DAG.getConstant(Idx, TLI.getVectorIdxTy())));
3136      else
3137        Ops.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, EltVT,
3138                                  Op1,
3139                                  DAG.getConstant(Idx - NumElems,
3140                                                  TLI.getVectorIdxTy())));
3141    }
3142
3143    Tmp1 = DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], Ops.size());
3144    // We may have changed the BUILD_VECTOR type. Cast it back to the Node type.
3145    Tmp1 = DAG.getNode(ISD::BITCAST, dl, Node->getValueType(0), Tmp1);
3146    Results.push_back(Tmp1);
3147    break;
3148  }
3149  case ISD::EXTRACT_ELEMENT: {
3150    EVT OpTy = Node->getOperand(0).getValueType();
3151    if (cast<ConstantSDNode>(Node->getOperand(1))->getZExtValue()) {
3152      // 1 -> Hi
3153      Tmp1 = DAG.getNode(ISD::SRL, dl, OpTy, Node->getOperand(0),
3154                         DAG.getConstant(OpTy.getSizeInBits()/2,
3155                    TLI.getShiftAmountTy(Node->getOperand(0).getValueType())));
3156      Tmp1 = DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0), Tmp1);
3157    } else {
3158      // 0 -> Lo
3159      Tmp1 = DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0),
3160                         Node->getOperand(0));
3161    }
3162    Results.push_back(Tmp1);
3163    break;
3164  }
3165  case ISD::STACKSAVE:
3166    // Expand to CopyFromReg if the target set
3167    // StackPointerRegisterToSaveRestore.
3168    if (unsigned SP = TLI.getStackPointerRegisterToSaveRestore()) {
3169      Results.push_back(DAG.getCopyFromReg(Node->getOperand(0), dl, SP,
3170                                           Node->getValueType(0)));
3171      Results.push_back(Results[0].getValue(1));
3172    } else {
3173      Results.push_back(DAG.getUNDEF(Node->getValueType(0)));
3174      Results.push_back(Node->getOperand(0));
3175    }
3176    break;
3177  case ISD::STACKRESTORE:
3178    // Expand to CopyToReg if the target set
3179    // StackPointerRegisterToSaveRestore.
3180    if (unsigned SP = TLI.getStackPointerRegisterToSaveRestore()) {
3181      Results.push_back(DAG.getCopyToReg(Node->getOperand(0), dl, SP,
3182                                         Node->getOperand(1)));
3183    } else {
3184      Results.push_back(Node->getOperand(0));
3185    }
3186    break;
3187  case ISD::FCOPYSIGN:
3188    Results.push_back(ExpandFCOPYSIGN(Node));
3189    break;
3190  case ISD::FNEG:
3191    // Expand Y = FNEG(X) ->  Y = SUB -0.0, X
3192    Tmp1 = DAG.getConstantFP(-0.0, Node->getValueType(0));
3193    Tmp1 = DAG.getNode(ISD::FSUB, dl, Node->getValueType(0), Tmp1,
3194                       Node->getOperand(0));
3195    Results.push_back(Tmp1);
3196    break;
3197  case ISD::FABS: {
3198    // Expand Y = FABS(X) -> Y = (X >u 0.0) ? X : fneg(X).
3199    EVT VT = Node->getValueType(0);
3200    Tmp1 = Node->getOperand(0);
3201    Tmp2 = DAG.getConstantFP(0.0, VT);
3202    Tmp2 = DAG.getSetCC(dl, getSetCCResultType(Tmp1.getValueType()),
3203                        Tmp1, Tmp2, ISD::SETUGT);
3204    Tmp3 = DAG.getNode(ISD::FNEG, dl, VT, Tmp1);
3205    Tmp1 = DAG.getSelect(dl, VT, Tmp2, Tmp1, Tmp3);
3206    Results.push_back(Tmp1);
3207    break;
3208  }
3209  case ISD::FSQRT:
3210    Results.push_back(ExpandFPLibCall(Node, RTLIB::SQRT_F32, RTLIB::SQRT_F64,
3211                                      RTLIB::SQRT_F80, RTLIB::SQRT_F128,
3212                                      RTLIB::SQRT_PPCF128));
3213    break;
3214  case ISD::FSIN:
3215  case ISD::FCOS: {
3216    EVT VT = Node->getValueType(0);
3217    bool isSIN = Node->getOpcode() == ISD::FSIN;
3218    // Turn fsin / fcos into ISD::FSINCOS node if there are a pair of fsin /
3219    // fcos which share the same operand and both are used.
3220    if ((TLI.isOperationLegalOrCustom(ISD::FSINCOS, VT) ||
3221         canCombineSinCosLibcall(Node, TLI, TM))
3222        && useSinCos(Node)) {
3223      SDVTList VTs = DAG.getVTList(VT, VT);
3224      Tmp1 = DAG.getNode(ISD::FSINCOS, dl, VTs, Node->getOperand(0));
3225      if (!isSIN)
3226        Tmp1 = Tmp1.getValue(1);
3227      Results.push_back(Tmp1);
3228    } else if (isSIN) {
3229      Results.push_back(ExpandFPLibCall(Node, RTLIB::SIN_F32, RTLIB::SIN_F64,
3230                                        RTLIB::SIN_F80, RTLIB::SIN_F128,
3231                                        RTLIB::SIN_PPCF128));
3232    } else {
3233      Results.push_back(ExpandFPLibCall(Node, RTLIB::COS_F32, RTLIB::COS_F64,
3234                                        RTLIB::COS_F80, RTLIB::COS_F128,
3235                                        RTLIB::COS_PPCF128));
3236    }
3237    break;
3238  }
3239  case ISD::FSINCOS:
3240    // Expand into sincos libcall.
3241    ExpandSinCosLibCall(Node, Results);
3242    break;
3243  case ISD::FLOG:
3244    Results.push_back(ExpandFPLibCall(Node, RTLIB::LOG_F32, RTLIB::LOG_F64,
3245                                      RTLIB::LOG_F80, RTLIB::LOG_F128,
3246                                      RTLIB::LOG_PPCF128));
3247    break;
3248  case ISD::FLOG2:
3249    Results.push_back(ExpandFPLibCall(Node, RTLIB::LOG2_F32, RTLIB::LOG2_F64,
3250                                      RTLIB::LOG2_F80, RTLIB::LOG2_F128,
3251                                      RTLIB::LOG2_PPCF128));
3252    break;
3253  case ISD::FLOG10:
3254    Results.push_back(ExpandFPLibCall(Node, RTLIB::LOG10_F32, RTLIB::LOG10_F64,
3255                                      RTLIB::LOG10_F80, RTLIB::LOG10_F128,
3256                                      RTLIB::LOG10_PPCF128));
3257    break;
3258  case ISD::FEXP:
3259    Results.push_back(ExpandFPLibCall(Node, RTLIB::EXP_F32, RTLIB::EXP_F64,
3260                                      RTLIB::EXP_F80, RTLIB::EXP_F128,
3261                                      RTLIB::EXP_PPCF128));
3262    break;
3263  case ISD::FEXP2:
3264    Results.push_back(ExpandFPLibCall(Node, RTLIB::EXP2_F32, RTLIB::EXP2_F64,
3265                                      RTLIB::EXP2_F80, RTLIB::EXP2_F128,
3266                                      RTLIB::EXP2_PPCF128));
3267    break;
3268  case ISD::FTRUNC:
3269    Results.push_back(ExpandFPLibCall(Node, RTLIB::TRUNC_F32, RTLIB::TRUNC_F64,
3270                                      RTLIB::TRUNC_F80, RTLIB::TRUNC_F128,
3271                                      RTLIB::TRUNC_PPCF128));
3272    break;
3273  case ISD::FFLOOR:
3274    Results.push_back(ExpandFPLibCall(Node, RTLIB::FLOOR_F32, RTLIB::FLOOR_F64,
3275                                      RTLIB::FLOOR_F80, RTLIB::FLOOR_F128,
3276                                      RTLIB::FLOOR_PPCF128));
3277    break;
3278  case ISD::FCEIL:
3279    Results.push_back(ExpandFPLibCall(Node, RTLIB::CEIL_F32, RTLIB::CEIL_F64,
3280                                      RTLIB::CEIL_F80, RTLIB::CEIL_F128,
3281                                      RTLIB::CEIL_PPCF128));
3282    break;
3283  case ISD::FRINT:
3284    Results.push_back(ExpandFPLibCall(Node, RTLIB::RINT_F32, RTLIB::RINT_F64,
3285                                      RTLIB::RINT_F80, RTLIB::RINT_F128,
3286                                      RTLIB::RINT_PPCF128));
3287    break;
3288  case ISD::FNEARBYINT:
3289    Results.push_back(ExpandFPLibCall(Node, RTLIB::NEARBYINT_F32,
3290                                      RTLIB::NEARBYINT_F64,
3291                                      RTLIB::NEARBYINT_F80,
3292                                      RTLIB::NEARBYINT_F128,
3293                                      RTLIB::NEARBYINT_PPCF128));
3294    break;
3295  case ISD::FROUND:
3296    Results.push_back(ExpandFPLibCall(Node, RTLIB::ROUND_F32,
3297                                      RTLIB::ROUND_F64,
3298                                      RTLIB::ROUND_F80,
3299                                      RTLIB::ROUND_F128,
3300                                      RTLIB::ROUND_PPCF128));
3301    break;
3302  case ISD::FPOWI:
3303    Results.push_back(ExpandFPLibCall(Node, RTLIB::POWI_F32, RTLIB::POWI_F64,
3304                                      RTLIB::POWI_F80, RTLIB::POWI_F128,
3305                                      RTLIB::POWI_PPCF128));
3306    break;
3307  case ISD::FPOW:
3308    Results.push_back(ExpandFPLibCall(Node, RTLIB::POW_F32, RTLIB::POW_F64,
3309                                      RTLIB::POW_F80, RTLIB::POW_F128,
3310                                      RTLIB::POW_PPCF128));
3311    break;
3312  case ISD::FDIV:
3313    Results.push_back(ExpandFPLibCall(Node, RTLIB::DIV_F32, RTLIB::DIV_F64,
3314                                      RTLIB::DIV_F80, RTLIB::DIV_F128,
3315                                      RTLIB::DIV_PPCF128));
3316    break;
3317  case ISD::FREM:
3318    Results.push_back(ExpandFPLibCall(Node, RTLIB::REM_F32, RTLIB::REM_F64,
3319                                      RTLIB::REM_F80, RTLIB::REM_F128,
3320                                      RTLIB::REM_PPCF128));
3321    break;
3322  case ISD::FMA:
3323    Results.push_back(ExpandFPLibCall(Node, RTLIB::FMA_F32, RTLIB::FMA_F64,
3324                                      RTLIB::FMA_F80, RTLIB::FMA_F128,
3325                                      RTLIB::FMA_PPCF128));
3326    break;
3327  case ISD::FP16_TO_FP32:
3328    Results.push_back(ExpandLibCall(RTLIB::FPEXT_F16_F32, Node, false));
3329    break;
3330  case ISD::FP32_TO_FP16:
3331    Results.push_back(ExpandLibCall(RTLIB::FPROUND_F32_F16, Node, false));
3332    break;
3333  case ISD::ConstantFP: {
3334    ConstantFPSDNode *CFP = cast<ConstantFPSDNode>(Node);
3335    // Check to see if this FP immediate is already legal.
3336    // If this is a legal constant, turn it into a TargetConstantFP node.
3337    if (!TLI.isFPImmLegal(CFP->getValueAPF(), Node->getValueType(0)))
3338      Results.push_back(ExpandConstantFP(CFP, true));
3339    break;
3340  }
3341  case ISD::FSUB: {
3342    EVT VT = Node->getValueType(0);
3343    assert(TLI.isOperationLegalOrCustom(ISD::FADD, VT) &&
3344           TLI.isOperationLegalOrCustom(ISD::FNEG, VT) &&
3345           "Don't know how to expand this FP subtraction!");
3346    Tmp1 = DAG.getNode(ISD::FNEG, dl, VT, Node->getOperand(1));
3347    Tmp1 = DAG.getNode(ISD::FADD, dl, VT, Node->getOperand(0), Tmp1);
3348    Results.push_back(Tmp1);
3349    break;
3350  }
3351  case ISD::SUB: {
3352    EVT VT = Node->getValueType(0);
3353    assert(TLI.isOperationLegalOrCustom(ISD::ADD, VT) &&
3354           TLI.isOperationLegalOrCustom(ISD::XOR, VT) &&
3355           "Don't know how to expand this subtraction!");
3356    Tmp1 = DAG.getNode(ISD::XOR, dl, VT, Node->getOperand(1),
3357               DAG.getConstant(APInt::getAllOnesValue(VT.getSizeInBits()), VT));
3358    Tmp1 = DAG.getNode(ISD::ADD, dl, VT, Tmp1, DAG.getConstant(1, VT));
3359    Results.push_back(DAG.getNode(ISD::ADD, dl, VT, Node->getOperand(0), Tmp1));
3360    break;
3361  }
3362  case ISD::UREM:
3363  case ISD::SREM: {
3364    EVT VT = Node->getValueType(0);
3365    bool isSigned = Node->getOpcode() == ISD::SREM;
3366    unsigned DivOpc = isSigned ? ISD::SDIV : ISD::UDIV;
3367    unsigned DivRemOpc = isSigned ? ISD::SDIVREM : ISD::UDIVREM;
3368    Tmp2 = Node->getOperand(0);
3369    Tmp3 = Node->getOperand(1);
3370    if (TLI.isOperationLegalOrCustom(DivRemOpc, VT) ||
3371        (isDivRemLibcallAvailable(Node, isSigned, TLI) &&
3372         // If div is legal, it's better to do the normal expansion
3373         !TLI.isOperationLegalOrCustom(DivOpc, Node->getValueType(0)) &&
3374         useDivRem(Node, isSigned, false))) {
3375      SDVTList VTs = DAG.getVTList(VT, VT);
3376      Tmp1 = DAG.getNode(DivRemOpc, dl, VTs, Tmp2, Tmp3).getValue(1);
3377    } else if (TLI.isOperationLegalOrCustom(DivOpc, VT)) {
3378      // X % Y -> X-X/Y*Y
3379      Tmp1 = DAG.getNode(DivOpc, dl, VT, Tmp2, Tmp3);
3380      Tmp1 = DAG.getNode(ISD::MUL, dl, VT, Tmp1, Tmp3);
3381      Tmp1 = DAG.getNode(ISD::SUB, dl, VT, Tmp2, Tmp1);
3382    } else if (isSigned)
3383      Tmp1 = ExpandIntLibCall(Node, true,
3384                              RTLIB::SREM_I8,
3385                              RTLIB::SREM_I16, RTLIB::SREM_I32,
3386                              RTLIB::SREM_I64, RTLIB::SREM_I128);
3387    else
3388      Tmp1 = ExpandIntLibCall(Node, false,
3389                              RTLIB::UREM_I8,
3390                              RTLIB::UREM_I16, RTLIB::UREM_I32,
3391                              RTLIB::UREM_I64, RTLIB::UREM_I128);
3392    Results.push_back(Tmp1);
3393    break;
3394  }
3395  case ISD::UDIV:
3396  case ISD::SDIV: {
3397    bool isSigned = Node->getOpcode() == ISD::SDIV;
3398    unsigned DivRemOpc = isSigned ? ISD::SDIVREM : ISD::UDIVREM;
3399    EVT VT = Node->getValueType(0);
3400    SDVTList VTs = DAG.getVTList(VT, VT);
3401    if (TLI.isOperationLegalOrCustom(DivRemOpc, VT) ||
3402        (isDivRemLibcallAvailable(Node, isSigned, TLI) &&
3403         useDivRem(Node, isSigned, true)))
3404      Tmp1 = DAG.getNode(DivRemOpc, dl, VTs, Node->getOperand(0),
3405                         Node->getOperand(1));
3406    else if (isSigned)
3407      Tmp1 = ExpandIntLibCall(Node, true,
3408                              RTLIB::SDIV_I8,
3409                              RTLIB::SDIV_I16, RTLIB::SDIV_I32,
3410                              RTLIB::SDIV_I64, RTLIB::SDIV_I128);
3411    else
3412      Tmp1 = ExpandIntLibCall(Node, false,
3413                              RTLIB::UDIV_I8,
3414                              RTLIB::UDIV_I16, RTLIB::UDIV_I32,
3415                              RTLIB::UDIV_I64, RTLIB::UDIV_I128);
3416    Results.push_back(Tmp1);
3417    break;
3418  }
3419  case ISD::MULHU:
3420  case ISD::MULHS: {
3421    unsigned ExpandOpcode = Node->getOpcode() == ISD::MULHU ? ISD::UMUL_LOHI :
3422                                                              ISD::SMUL_LOHI;
3423    EVT VT = Node->getValueType(0);
3424    SDVTList VTs = DAG.getVTList(VT, VT);
3425    assert(TLI.isOperationLegalOrCustom(ExpandOpcode, VT) &&
3426           "If this wasn't legal, it shouldn't have been created!");
3427    Tmp1 = DAG.getNode(ExpandOpcode, dl, VTs, Node->getOperand(0),
3428                       Node->getOperand(1));
3429    Results.push_back(Tmp1.getValue(1));
3430    break;
3431  }
3432  case ISD::SDIVREM:
3433  case ISD::UDIVREM:
3434    // Expand into divrem libcall
3435    ExpandDivRemLibCall(Node, Results);
3436    break;
3437  case ISD::MUL: {
3438    EVT VT = Node->getValueType(0);
3439    SDVTList VTs = DAG.getVTList(VT, VT);
3440    // See if multiply or divide can be lowered using two-result operations.
3441    // We just need the low half of the multiply; try both the signed
3442    // and unsigned forms. If the target supports both SMUL_LOHI and
3443    // UMUL_LOHI, form a preference by checking which forms of plain
3444    // MULH it supports.
3445    bool HasSMUL_LOHI = TLI.isOperationLegalOrCustom(ISD::SMUL_LOHI, VT);
3446    bool HasUMUL_LOHI = TLI.isOperationLegalOrCustom(ISD::UMUL_LOHI, VT);
3447    bool HasMULHS = TLI.isOperationLegalOrCustom(ISD::MULHS, VT);
3448    bool HasMULHU = TLI.isOperationLegalOrCustom(ISD::MULHU, VT);
3449    unsigned OpToUse = 0;
3450    if (HasSMUL_LOHI && !HasMULHS) {
3451      OpToUse = ISD::SMUL_LOHI;
3452    } else if (HasUMUL_LOHI && !HasMULHU) {
3453      OpToUse = ISD::UMUL_LOHI;
3454    } else if (HasSMUL_LOHI) {
3455      OpToUse = ISD::SMUL_LOHI;
3456    } else if (HasUMUL_LOHI) {
3457      OpToUse = ISD::UMUL_LOHI;
3458    }
3459    if (OpToUse) {
3460      Results.push_back(DAG.getNode(OpToUse, dl, VTs, Node->getOperand(0),
3461                                    Node->getOperand(1)));
3462      break;
3463    }
3464    Tmp1 = ExpandIntLibCall(Node, false,
3465                            RTLIB::MUL_I8,
3466                            RTLIB::MUL_I16, RTLIB::MUL_I32,
3467                            RTLIB::MUL_I64, RTLIB::MUL_I128);
3468    Results.push_back(Tmp1);
3469    break;
3470  }
3471  case ISD::SADDO:
3472  case ISD::SSUBO: {
3473    SDValue LHS = Node->getOperand(0);
3474    SDValue RHS = Node->getOperand(1);
3475    SDValue Sum = DAG.getNode(Node->getOpcode() == ISD::SADDO ?
3476                              ISD::ADD : ISD::SUB, dl, LHS.getValueType(),
3477                              LHS, RHS);
3478    Results.push_back(Sum);
3479    EVT OType = Node->getValueType(1);
3480
3481    SDValue Zero = DAG.getConstant(0, LHS.getValueType());
3482
3483    //   LHSSign -> LHS >= 0
3484    //   RHSSign -> RHS >= 0
3485    //   SumSign -> Sum >= 0
3486    //
3487    //   Add:
3488    //   Overflow -> (LHSSign == RHSSign) && (LHSSign != SumSign)
3489    //   Sub:
3490    //   Overflow -> (LHSSign != RHSSign) && (LHSSign != SumSign)
3491    //
3492    SDValue LHSSign = DAG.getSetCC(dl, OType, LHS, Zero, ISD::SETGE);
3493    SDValue RHSSign = DAG.getSetCC(dl, OType, RHS, Zero, ISD::SETGE);
3494    SDValue SignsMatch = DAG.getSetCC(dl, OType, LHSSign, RHSSign,
3495                                      Node->getOpcode() == ISD::SADDO ?
3496                                      ISD::SETEQ : ISD::SETNE);
3497
3498    SDValue SumSign = DAG.getSetCC(dl, OType, Sum, Zero, ISD::SETGE);
3499    SDValue SumSignNE = DAG.getSetCC(dl, OType, LHSSign, SumSign, ISD::SETNE);
3500
3501    SDValue Cmp = DAG.getNode(ISD::AND, dl, OType, SignsMatch, SumSignNE);
3502    Results.push_back(Cmp);
3503    break;
3504  }
3505  case ISD::UADDO:
3506  case ISD::USUBO: {
3507    SDValue LHS = Node->getOperand(0);
3508    SDValue RHS = Node->getOperand(1);
3509    SDValue Sum = DAG.getNode(Node->getOpcode() == ISD::UADDO ?
3510                              ISD::ADD : ISD::SUB, dl, LHS.getValueType(),
3511                              LHS, RHS);
3512    Results.push_back(Sum);
3513    Results.push_back(DAG.getSetCC(dl, Node->getValueType(1), Sum, LHS,
3514                                   Node->getOpcode () == ISD::UADDO ?
3515                                   ISD::SETULT : ISD::SETUGT));
3516    break;
3517  }
3518  case ISD::UMULO:
3519  case ISD::SMULO: {
3520    EVT VT = Node->getValueType(0);
3521    EVT WideVT = EVT::getIntegerVT(*DAG.getContext(), VT.getSizeInBits() * 2);
3522    SDValue LHS = Node->getOperand(0);
3523    SDValue RHS = Node->getOperand(1);
3524    SDValue BottomHalf;
3525    SDValue TopHalf;
3526    static const unsigned Ops[2][3] =
3527        { { ISD::MULHU, ISD::UMUL_LOHI, ISD::ZERO_EXTEND },
3528          { ISD::MULHS, ISD::SMUL_LOHI, ISD::SIGN_EXTEND }};
3529    bool isSigned = Node->getOpcode() == ISD::SMULO;
3530    if (TLI.isOperationLegalOrCustom(Ops[isSigned][0], VT)) {
3531      BottomHalf = DAG.getNode(ISD::MUL, dl, VT, LHS, RHS);
3532      TopHalf = DAG.getNode(Ops[isSigned][0], dl, VT, LHS, RHS);
3533    } else if (TLI.isOperationLegalOrCustom(Ops[isSigned][1], VT)) {
3534      BottomHalf = DAG.getNode(Ops[isSigned][1], dl, DAG.getVTList(VT, VT), LHS,
3535                               RHS);
3536      TopHalf = BottomHalf.getValue(1);
3537    } else if (TLI.isTypeLegal(EVT::getIntegerVT(*DAG.getContext(),
3538                                                 VT.getSizeInBits() * 2))) {
3539      LHS = DAG.getNode(Ops[isSigned][2], dl, WideVT, LHS);
3540      RHS = DAG.getNode(Ops[isSigned][2], dl, WideVT, RHS);
3541      Tmp1 = DAG.getNode(ISD::MUL, dl, WideVT, LHS, RHS);
3542      BottomHalf = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, VT, Tmp1,
3543                               DAG.getIntPtrConstant(0));
3544      TopHalf = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, VT, Tmp1,
3545                            DAG.getIntPtrConstant(1));
3546    } else {
3547      // We can fall back to a libcall with an illegal type for the MUL if we
3548      // have a libcall big enough.
3549      // Also, we can fall back to a division in some cases, but that's a big
3550      // performance hit in the general case.
3551      RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
3552      if (WideVT == MVT::i16)
3553        LC = RTLIB::MUL_I16;
3554      else if (WideVT == MVT::i32)
3555        LC = RTLIB::MUL_I32;
3556      else if (WideVT == MVT::i64)
3557        LC = RTLIB::MUL_I64;
3558      else if (WideVT == MVT::i128)
3559        LC = RTLIB::MUL_I128;
3560      assert(LC != RTLIB::UNKNOWN_LIBCALL && "Cannot expand this operation!");
3561
3562      // The high part is obtained by SRA'ing all but one of the bits of low
3563      // part.
3564      unsigned LoSize = VT.getSizeInBits();
3565      SDValue HiLHS = DAG.getNode(ISD::SRA, dl, VT, RHS,
3566                                DAG.getConstant(LoSize-1, TLI.getPointerTy()));
3567      SDValue HiRHS = DAG.getNode(ISD::SRA, dl, VT, LHS,
3568                                DAG.getConstant(LoSize-1, TLI.getPointerTy()));
3569
3570      // Here we're passing the 2 arguments explicitly as 4 arguments that are
3571      // pre-lowered to the correct types. This all depends upon WideVT not
3572      // being a legal type for the architecture and thus has to be split to
3573      // two arguments.
3574      SDValue Args[] = { LHS, HiLHS, RHS, HiRHS };
3575      SDValue Ret = ExpandLibCall(LC, WideVT, Args, 4, isSigned, dl);
3576      BottomHalf = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, VT, Ret,
3577                               DAG.getIntPtrConstant(0));
3578      TopHalf = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, VT, Ret,
3579                            DAG.getIntPtrConstant(1));
3580      // Ret is a node with an illegal type. Because such things are not
3581      // generally permitted during this phase of legalization, delete the
3582      // node. The above EXTRACT_ELEMENT nodes should have been folded.
3583      DAG.DeleteNode(Ret.getNode());
3584    }
3585
3586    if (isSigned) {
3587      Tmp1 = DAG.getConstant(VT.getSizeInBits() - 1,
3588                             TLI.getShiftAmountTy(BottomHalf.getValueType()));
3589      Tmp1 = DAG.getNode(ISD::SRA, dl, VT, BottomHalf, Tmp1);
3590      TopHalf = DAG.getSetCC(dl, getSetCCResultType(VT), TopHalf, Tmp1,
3591                             ISD::SETNE);
3592    } else {
3593      TopHalf = DAG.getSetCC(dl, getSetCCResultType(VT), TopHalf,
3594                             DAG.getConstant(0, VT), ISD::SETNE);
3595    }
3596    Results.push_back(BottomHalf);
3597    Results.push_back(TopHalf);
3598    break;
3599  }
3600  case ISD::BUILD_PAIR: {
3601    EVT PairTy = Node->getValueType(0);
3602    Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, PairTy, Node->getOperand(0));
3603    Tmp2 = DAG.getNode(ISD::ANY_EXTEND, dl, PairTy, Node->getOperand(1));
3604    Tmp2 = DAG.getNode(ISD::SHL, dl, PairTy, Tmp2,
3605                       DAG.getConstant(PairTy.getSizeInBits()/2,
3606                                       TLI.getShiftAmountTy(PairTy)));
3607    Results.push_back(DAG.getNode(ISD::OR, dl, PairTy, Tmp1, Tmp2));
3608    break;
3609  }
3610  case ISD::SELECT:
3611    Tmp1 = Node->getOperand(0);
3612    Tmp2 = Node->getOperand(1);
3613    Tmp3 = Node->getOperand(2);
3614    if (Tmp1.getOpcode() == ISD::SETCC) {
3615      Tmp1 = DAG.getSelectCC(dl, Tmp1.getOperand(0), Tmp1.getOperand(1),
3616                             Tmp2, Tmp3,
3617                             cast<CondCodeSDNode>(Tmp1.getOperand(2))->get());
3618    } else {
3619      Tmp1 = DAG.getSelectCC(dl, Tmp1,
3620                             DAG.getConstant(0, Tmp1.getValueType()),
3621                             Tmp2, Tmp3, ISD::SETNE);
3622    }
3623    Results.push_back(Tmp1);
3624    break;
3625  case ISD::BR_JT: {
3626    SDValue Chain = Node->getOperand(0);
3627    SDValue Table = Node->getOperand(1);
3628    SDValue Index = Node->getOperand(2);
3629
3630    EVT PTy = TLI.getPointerTy();
3631
3632    const DataLayout &TD = *TLI.getDataLayout();
3633    unsigned EntrySize =
3634      DAG.getMachineFunction().getJumpTableInfo()->getEntrySize(TD);
3635
3636    Index = DAG.getNode(ISD::MUL, dl, Index.getValueType(),
3637                       Index, DAG.getConstant(EntrySize, Index.getValueType()));
3638    SDValue Addr = DAG.getNode(ISD::ADD, dl, Index.getValueType(),
3639                               Index, Table);
3640
3641    EVT MemVT = EVT::getIntegerVT(*DAG.getContext(), EntrySize * 8);
3642    SDValue LD = DAG.getExtLoad(ISD::SEXTLOAD, dl, PTy, Chain, Addr,
3643                                MachinePointerInfo::getJumpTable(), MemVT,
3644                                false, false, 0);
3645    Addr = LD;
3646    if (TM.getRelocationModel() == Reloc::PIC_) {
3647      // For PIC, the sequence is:
3648      // BRIND(load(Jumptable + index) + RelocBase)
3649      // RelocBase can be JumpTable, GOT or some sort of global base.
3650      Addr = DAG.getNode(ISD::ADD, dl, PTy, Addr,
3651                          TLI.getPICJumpTableRelocBase(Table, DAG));
3652    }
3653    Tmp1 = DAG.getNode(ISD::BRIND, dl, MVT::Other, LD.getValue(1), Addr);
3654    Results.push_back(Tmp1);
3655    break;
3656  }
3657  case ISD::BRCOND:
3658    // Expand brcond's setcc into its constituent parts and create a BR_CC
3659    // Node.
3660    Tmp1 = Node->getOperand(0);
3661    Tmp2 = Node->getOperand(1);
3662    if (Tmp2.getOpcode() == ISD::SETCC) {
3663      Tmp1 = DAG.getNode(ISD::BR_CC, dl, MVT::Other,
3664                         Tmp1, Tmp2.getOperand(2),
3665                         Tmp2.getOperand(0), Tmp2.getOperand(1),
3666                         Node->getOperand(2));
3667    } else {
3668      // We test only the i1 bit.  Skip the AND if UNDEF.
3669      Tmp3 = (Tmp2.getOpcode() == ISD::UNDEF) ? Tmp2 :
3670        DAG.getNode(ISD::AND, dl, Tmp2.getValueType(), Tmp2,
3671                    DAG.getConstant(1, Tmp2.getValueType()));
3672      Tmp1 = DAG.getNode(ISD::BR_CC, dl, MVT::Other, Tmp1,
3673                         DAG.getCondCode(ISD::SETNE), Tmp3,
3674                         DAG.getConstant(0, Tmp3.getValueType()),
3675                         Node->getOperand(2));
3676    }
3677    Results.push_back(Tmp1);
3678    break;
3679  case ISD::SETCC: {
3680    Tmp1 = Node->getOperand(0);
3681    Tmp2 = Node->getOperand(1);
3682    Tmp3 = Node->getOperand(2);
3683    bool Legalized = LegalizeSetCCCondCode(Node->getValueType(0), Tmp1, Tmp2,
3684                                           Tmp3, dl);
3685
3686    if (Legalized) {
3687      // If we exapanded the SETCC by swapping LHS and RHS, create a new SETCC
3688      // node.
3689      if (Tmp3.getNode())
3690        Tmp1 = DAG.getNode(ISD::SETCC, dl, Node->getValueType(0),
3691                           Tmp1, Tmp2, Tmp3);
3692
3693      Results.push_back(Tmp1);
3694      break;
3695    }
3696
3697    // Otherwise, SETCC for the given comparison type must be completely
3698    // illegal; expand it into a SELECT_CC.
3699    EVT VT = Node->getValueType(0);
3700    int TrueValue;
3701    switch (TLI.getBooleanContents(VT.isVector())) {
3702    case TargetLowering::ZeroOrOneBooleanContent:
3703    case TargetLowering::UndefinedBooleanContent:
3704      TrueValue = 1;
3705      break;
3706    case TargetLowering::ZeroOrNegativeOneBooleanContent:
3707      TrueValue = -1;
3708      break;
3709    }
3710    Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, VT, Tmp1, Tmp2,
3711                       DAG.getConstant(TrueValue, VT), DAG.getConstant(0, VT),
3712                       Tmp3);
3713    Results.push_back(Tmp1);
3714    break;
3715  }
3716  case ISD::SELECT_CC: {
3717    Tmp1 = Node->getOperand(0);   // LHS
3718    Tmp2 = Node->getOperand(1);   // RHS
3719    Tmp3 = Node->getOperand(2);   // True
3720    Tmp4 = Node->getOperand(3);   // False
3721    SDValue CC = Node->getOperand(4);
3722
3723    bool Legalized = false;
3724    // Try to legalize by inverting the condition.  This is for targets that
3725    // might support an ordered version of a condition, but not the unordered
3726    // version (or vice versa).
3727    ISD::CondCode InvCC = ISD::getSetCCInverse(cast<CondCodeSDNode>(CC)->get(),
3728                                               Tmp1.getValueType().isInteger());
3729    if (TLI.isCondCodeLegal(InvCC, Tmp1.getSimpleValueType())) {
3730      // Use the new condition code and swap true and false
3731      Legalized = true;
3732      Tmp1 = DAG.getSelectCC(dl, Tmp1, Tmp2, Tmp4, Tmp3, InvCC);
3733    } else {
3734      // If The inverse is not legal, then try to swap the arguments using
3735      // the inverse condition code.
3736      ISD::CondCode SwapInvCC = ISD::getSetCCSwappedOperands(InvCC);
3737      if (TLI.isCondCodeLegal(SwapInvCC, Tmp1.getSimpleValueType())) {
3738        // The swapped inverse condition is legal, so swap true and false,
3739        // lhs and rhs.
3740        Legalized = true;
3741        Tmp1 = DAG.getSelectCC(dl, Tmp2, Tmp1, Tmp4, Tmp3, SwapInvCC);
3742      }
3743    }
3744
3745    if (!Legalized) {
3746      Legalized = LegalizeSetCCCondCode(
3747          getSetCCResultType(Tmp1.getValueType()), Tmp1, Tmp2, CC, dl);
3748
3749      assert(Legalized && "Can't legalize SELECT_CC with legal condition!");
3750      // If we exapanded the SETCC by swapping LHS and RHS, create a new
3751      // SELECT_CC node.
3752      if (CC.getNode()) {
3753        Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, Node->getValueType(0),
3754                           Tmp1, Tmp2, Tmp3, Tmp4, CC);
3755      } else {
3756        Tmp2 = DAG.getConstant(0, Tmp1.getValueType());
3757        CC = DAG.getCondCode(ISD::SETNE);
3758        Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, Node->getValueType(0), Tmp1, Tmp2,
3759                           Tmp3, Tmp4, CC);
3760      }
3761    }
3762    Results.push_back(Tmp1);
3763    break;
3764  }
3765  case ISD::BR_CC: {
3766    Tmp1 = Node->getOperand(0);              // Chain
3767    Tmp2 = Node->getOperand(2);              // LHS
3768    Tmp3 = Node->getOperand(3);              // RHS
3769    Tmp4 = Node->getOperand(1);              // CC
3770
3771    bool Legalized = LegalizeSetCCCondCode(getSetCCResultType(
3772        Tmp2.getValueType()), Tmp2, Tmp3, Tmp4, dl);
3773    (void)Legalized;
3774    assert(Legalized && "Can't legalize BR_CC with legal condition!");
3775
3776    // If we exapanded the SETCC by swapping LHS and RHS, create a new BR_CC
3777    // node.
3778    if (Tmp4.getNode()) {
3779      Tmp1 = DAG.getNode(ISD::BR_CC, dl, Node->getValueType(0), Tmp1,
3780                         Tmp4, Tmp2, Tmp3, Node->getOperand(4));
3781    } else {
3782      Tmp3 = DAG.getConstant(0, Tmp2.getValueType());
3783      Tmp4 = DAG.getCondCode(ISD::SETNE);
3784      Tmp1 = DAG.getNode(ISD::BR_CC, dl, Node->getValueType(0), Tmp1, Tmp4, Tmp2,
3785                         Tmp3, Node->getOperand(4));
3786    }
3787    Results.push_back(Tmp1);
3788    break;
3789  }
3790  case ISD::BUILD_VECTOR:
3791    Results.push_back(ExpandBUILD_VECTOR(Node));
3792    break;
3793  case ISD::SRA:
3794  case ISD::SRL:
3795  case ISD::SHL: {
3796    // Scalarize vector SRA/SRL/SHL.
3797    EVT VT = Node->getValueType(0);
3798    assert(VT.isVector() && "Unable to legalize non-vector shift");
3799    assert(TLI.isTypeLegal(VT.getScalarType())&& "Element type must be legal");
3800    unsigned NumElem = VT.getVectorNumElements();
3801
3802    SmallVector<SDValue, 8> Scalars;
3803    for (unsigned Idx = 0; Idx < NumElem; Idx++) {
3804      SDValue Ex = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl,
3805                               VT.getScalarType(),
3806                               Node->getOperand(0), DAG.getConstant(Idx,
3807                                                    TLI.getVectorIdxTy()));
3808      SDValue Sh = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl,
3809                               VT.getScalarType(),
3810                               Node->getOperand(1), DAG.getConstant(Idx,
3811                                                    TLI.getVectorIdxTy()));
3812      Scalars.push_back(DAG.getNode(Node->getOpcode(), dl,
3813                                    VT.getScalarType(), Ex, Sh));
3814    }
3815    SDValue Result =
3816      DAG.getNode(ISD::BUILD_VECTOR, dl, Node->getValueType(0),
3817                  &Scalars[0], Scalars.size());
3818    ReplaceNode(SDValue(Node, 0), Result);
3819    break;
3820  }
3821  case ISD::GLOBAL_OFFSET_TABLE:
3822  case ISD::GlobalAddress:
3823  case ISD::GlobalTLSAddress:
3824  case ISD::ExternalSymbol:
3825  case ISD::ConstantPool:
3826  case ISD::JumpTable:
3827  case ISD::INTRINSIC_W_CHAIN:
3828  case ISD::INTRINSIC_WO_CHAIN:
3829  case ISD::INTRINSIC_VOID:
3830    // FIXME: Custom lowering for these operations shouldn't return null!
3831    break;
3832  }
3833
3834  // Replace the original node with the legalized result.
3835  if (!Results.empty())
3836    ReplaceNode(Node, Results.data());
3837}
3838
3839void SelectionDAGLegalize::PromoteNode(SDNode *Node) {
3840  SmallVector<SDValue, 8> Results;
3841  MVT OVT = Node->getSimpleValueType(0);
3842  if (Node->getOpcode() == ISD::UINT_TO_FP ||
3843      Node->getOpcode() == ISD::SINT_TO_FP ||
3844      Node->getOpcode() == ISD::SETCC) {
3845    OVT = Node->getOperand(0).getSimpleValueType();
3846  }
3847  MVT NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), OVT);
3848  SDLoc dl(Node);
3849  SDValue Tmp1, Tmp2, Tmp3;
3850  switch (Node->getOpcode()) {
3851  case ISD::CTTZ:
3852  case ISD::CTTZ_ZERO_UNDEF:
3853  case ISD::CTLZ:
3854  case ISD::CTLZ_ZERO_UNDEF:
3855  case ISD::CTPOP:
3856    // Zero extend the argument.
3857    Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, NVT, Node->getOperand(0));
3858    // Perform the larger operation. For CTPOP and CTTZ_ZERO_UNDEF, this is
3859    // already the correct result.
3860    Tmp1 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1);
3861    if (Node->getOpcode() == ISD::CTTZ) {
3862      // FIXME: This should set a bit in the zero extended value instead.
3863      Tmp2 = DAG.getSetCC(dl, getSetCCResultType(NVT),
3864                          Tmp1, DAG.getConstant(NVT.getSizeInBits(), NVT),
3865                          ISD::SETEQ);
3866      Tmp1 = DAG.getSelect(dl, NVT, Tmp2,
3867                           DAG.getConstant(OVT.getSizeInBits(), NVT), Tmp1);
3868    } else if (Node->getOpcode() == ISD::CTLZ ||
3869               Node->getOpcode() == ISD::CTLZ_ZERO_UNDEF) {
3870      // Tmp1 = Tmp1 - (sizeinbits(NVT) - sizeinbits(Old VT))
3871      Tmp1 = DAG.getNode(ISD::SUB, dl, NVT, Tmp1,
3872                          DAG.getConstant(NVT.getSizeInBits() -
3873                                          OVT.getSizeInBits(), NVT));
3874    }
3875    Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp1));
3876    break;
3877  case ISD::BSWAP: {
3878    unsigned DiffBits = NVT.getSizeInBits() - OVT.getSizeInBits();
3879    Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, NVT, Node->getOperand(0));
3880    Tmp1 = DAG.getNode(ISD::BSWAP, dl, NVT, Tmp1);
3881    Tmp1 = DAG.getNode(ISD::SRL, dl, NVT, Tmp1,
3882                          DAG.getConstant(DiffBits, TLI.getShiftAmountTy(NVT)));
3883    Results.push_back(Tmp1);
3884    break;
3885  }
3886  case ISD::FP_TO_UINT:
3887  case ISD::FP_TO_SINT:
3888    Tmp1 = PromoteLegalFP_TO_INT(Node->getOperand(0), Node->getValueType(0),
3889                                 Node->getOpcode() == ISD::FP_TO_SINT, dl);
3890    Results.push_back(Tmp1);
3891    break;
3892  case ISD::UINT_TO_FP:
3893  case ISD::SINT_TO_FP:
3894    Tmp1 = PromoteLegalINT_TO_FP(Node->getOperand(0), Node->getValueType(0),
3895                                 Node->getOpcode() == ISD::SINT_TO_FP, dl);
3896    Results.push_back(Tmp1);
3897    break;
3898  case ISD::VAARG: {
3899    SDValue Chain = Node->getOperand(0); // Get the chain.
3900    SDValue Ptr = Node->getOperand(1); // Get the pointer.
3901
3902    unsigned TruncOp;
3903    if (OVT.isVector()) {
3904      TruncOp = ISD::BITCAST;
3905    } else {
3906      assert(OVT.isInteger()
3907        && "VAARG promotion is supported only for vectors or integer types");
3908      TruncOp = ISD::TRUNCATE;
3909    }
3910
3911    // Perform the larger operation, then convert back
3912    Tmp1 = DAG.getVAArg(NVT, dl, Chain, Ptr, Node->getOperand(2),
3913             Node->getConstantOperandVal(3));
3914    Chain = Tmp1.getValue(1);
3915
3916    Tmp2 = DAG.getNode(TruncOp, dl, OVT, Tmp1);
3917
3918    // Modified the chain result - switch anything that used the old chain to
3919    // use the new one.
3920    DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 0), Tmp2);
3921    DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 1), Chain);
3922    ReplacedNode(Node);
3923    break;
3924  }
3925  case ISD::AND:
3926  case ISD::OR:
3927  case ISD::XOR: {
3928    unsigned ExtOp, TruncOp;
3929    if (OVT.isVector()) {
3930      ExtOp   = ISD::BITCAST;
3931      TruncOp = ISD::BITCAST;
3932    } else {
3933      assert(OVT.isInteger() && "Cannot promote logic operation");
3934      ExtOp   = ISD::ANY_EXTEND;
3935      TruncOp = ISD::TRUNCATE;
3936    }
3937    // Promote each of the values to the new type.
3938    Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(0));
3939    Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
3940    // Perform the larger operation, then convert back
3941    Tmp1 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2);
3942    Results.push_back(DAG.getNode(TruncOp, dl, OVT, Tmp1));
3943    break;
3944  }
3945  case ISD::SELECT: {
3946    unsigned ExtOp, TruncOp;
3947    if (Node->getValueType(0).isVector()) {
3948      ExtOp   = ISD::BITCAST;
3949      TruncOp = ISD::BITCAST;
3950    } else if (Node->getValueType(0).isInteger()) {
3951      ExtOp   = ISD::ANY_EXTEND;
3952      TruncOp = ISD::TRUNCATE;
3953    } else {
3954      ExtOp   = ISD::FP_EXTEND;
3955      TruncOp = ISD::FP_ROUND;
3956    }
3957    Tmp1 = Node->getOperand(0);
3958    // Promote each of the values to the new type.
3959    Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
3960    Tmp3 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(2));
3961    // Perform the larger operation, then round down.
3962    Tmp1 = DAG.getSelect(dl, NVT, Tmp1, Tmp2, Tmp3);
3963    if (TruncOp != ISD::FP_ROUND)
3964      Tmp1 = DAG.getNode(TruncOp, dl, Node->getValueType(0), Tmp1);
3965    else
3966      Tmp1 = DAG.getNode(TruncOp, dl, Node->getValueType(0), Tmp1,
3967                         DAG.getIntPtrConstant(0));
3968    Results.push_back(Tmp1);
3969    break;
3970  }
3971  case ISD::VECTOR_SHUFFLE: {
3972    ArrayRef<int> Mask = cast<ShuffleVectorSDNode>(Node)->getMask();
3973
3974    // Cast the two input vectors.
3975    Tmp1 = DAG.getNode(ISD::BITCAST, dl, NVT, Node->getOperand(0));
3976    Tmp2 = DAG.getNode(ISD::BITCAST, dl, NVT, Node->getOperand(1));
3977
3978    // Convert the shuffle mask to the right # elements.
3979    Tmp1 = ShuffleWithNarrowerEltType(NVT, OVT, dl, Tmp1, Tmp2, Mask);
3980    Tmp1 = DAG.getNode(ISD::BITCAST, dl, OVT, Tmp1);
3981    Results.push_back(Tmp1);
3982    break;
3983  }
3984  case ISD::SETCC: {
3985    unsigned ExtOp = ISD::FP_EXTEND;
3986    if (NVT.isInteger()) {
3987      ISD::CondCode CCCode =
3988        cast<CondCodeSDNode>(Node->getOperand(2))->get();
3989      ExtOp = isSignedIntSetCC(CCCode) ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND;
3990    }
3991    Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(0));
3992    Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
3993    Results.push_back(DAG.getNode(ISD::SETCC, dl, Node->getValueType(0),
3994                                  Tmp1, Tmp2, Node->getOperand(2)));
3995    break;
3996  }
3997  case ISD::FDIV:
3998  case ISD::FREM:
3999  case ISD::FPOW: {
4000    Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(0));
4001    Tmp2 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(1));
4002    Tmp3 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2);
4003    Results.push_back(DAG.getNode(ISD::FP_ROUND, dl, OVT,
4004                                  Tmp3, DAG.getIntPtrConstant(0)));
4005    break;
4006  }
4007  case ISD::FLOG2:
4008  case ISD::FEXP2:
4009  case ISD::FLOG:
4010  case ISD::FEXP: {
4011    Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(0));
4012    Tmp2 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1);
4013    Results.push_back(DAG.getNode(ISD::FP_ROUND, dl, OVT,
4014                                  Tmp2, DAG.getIntPtrConstant(0)));
4015    break;
4016  }
4017  }
4018
4019  // Replace the original node with the legalized result.
4020  if (!Results.empty())
4021    ReplaceNode(Node, Results.data());
4022}
4023
4024// SelectionDAG::Legalize - This is the entry point for the file.
4025//
4026void SelectionDAG::Legalize() {
4027  /// run - This is the main entry point to this class.
4028  ///
4029  SelectionDAGLegalize(*this).LegalizeDAG();
4030}
4031