LegalizeDAG.cpp revision 118cd9dbbad3a47f37dc1b1529ef920e4d5e13f6
1//===-- LegalizeDAG.cpp - Implement SelectionDAG::Legalize ----------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file was developed by the LLVM research group and is distributed under
6// the University of Illinois Open Source 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/CodeGen/MachineFunction.h"
16#include "llvm/CodeGen/MachineFrameInfo.h"
17#include "llvm/CodeGen/MachineJumpTableInfo.h"
18#include "llvm/Target/TargetFrameInfo.h"
19#include "llvm/Target/TargetLowering.h"
20#include "llvm/Target/TargetData.h"
21#include "llvm/Target/TargetMachine.h"
22#include "llvm/Target/TargetOptions.h"
23#include "llvm/CallingConv.h"
24#include "llvm/Constants.h"
25#include "llvm/DerivedTypes.h"
26#include "llvm/Support/MathExtras.h"
27#include "llvm/Support/CommandLine.h"
28#include "llvm/Support/Compiler.h"
29#include "llvm/ADT/DenseMap.h"
30#include "llvm/ADT/SmallVector.h"
31#include "llvm/ADT/SmallPtrSet.h"
32#include <map>
33using namespace llvm;
34
35#ifndef NDEBUG
36static cl::opt<bool>
37ViewLegalizeDAGs("view-legalize-dags", cl::Hidden,
38                 cl::desc("Pop up a window to show dags before legalize"));
39#else
40static const bool ViewLegalizeDAGs = 0;
41#endif
42
43//===----------------------------------------------------------------------===//
44/// SelectionDAGLegalize - This takes an arbitrary SelectionDAG as input and
45/// hacks on it until the target machine can handle it.  This involves
46/// eliminating value sizes the machine cannot handle (promoting small sizes to
47/// large sizes or splitting up large values into small values) as well as
48/// eliminating operations the machine cannot handle.
49///
50/// This code also does a small amount of optimization and recognition of idioms
51/// as part of its processing.  For example, if a target does not support a
52/// 'setcc' instruction efficiently, but does support 'brcc' instruction, this
53/// will attempt merge setcc and brc instructions into brcc's.
54///
55namespace {
56class VISIBILITY_HIDDEN SelectionDAGLegalize {
57  TargetLowering &TLI;
58  SelectionDAG &DAG;
59
60  // Libcall insertion helpers.
61
62  /// LastCALLSEQ_END - This keeps track of the CALLSEQ_END node that has been
63  /// legalized.  We use this to ensure that calls are properly serialized
64  /// against each other, including inserted libcalls.
65  SDOperand LastCALLSEQ_END;
66
67  /// IsLegalizingCall - This member is used *only* for purposes of providing
68  /// helpful assertions that a libcall isn't created while another call is
69  /// being legalized (which could lead to non-serialized call sequences).
70  bool IsLegalizingCall;
71
72  enum LegalizeAction {
73    Legal,      // The target natively supports this operation.
74    Promote,    // This operation should be executed in a larger type.
75    Expand      // Try to expand this to other ops, otherwise use a libcall.
76  };
77
78  /// ValueTypeActions - This is a bitvector that contains two bits for each
79  /// value type, where the two bits correspond to the LegalizeAction enum.
80  /// This can be queried with "getTypeAction(VT)".
81  TargetLowering::ValueTypeActionImpl ValueTypeActions;
82
83  /// LegalizedNodes - For nodes that are of legal width, and that have more
84  /// than one use, this map indicates what regularized operand to use.  This
85  /// allows us to avoid legalizing the same thing more than once.
86  DenseMap<SDOperand, SDOperand> LegalizedNodes;
87
88  /// PromotedNodes - For nodes that are below legal width, and that have more
89  /// than one use, this map indicates what promoted value to use.  This allows
90  /// us to avoid promoting the same thing more than once.
91  DenseMap<SDOperand, SDOperand> PromotedNodes;
92
93  /// ExpandedNodes - For nodes that need to be expanded this map indicates
94  /// which which operands are the expanded version of the input.  This allows
95  /// us to avoid expanding the same node more than once.
96  DenseMap<SDOperand, std::pair<SDOperand, SDOperand> > ExpandedNodes;
97
98  /// SplitNodes - For vector nodes that need to be split, this map indicates
99  /// which which operands are the split version of the input.  This allows us
100  /// to avoid splitting the same node more than once.
101  std::map<SDOperand, std::pair<SDOperand, SDOperand> > SplitNodes;
102
103  /// ScalarizedNodes - For nodes that need to be converted from vector types to
104  /// scalar types, this contains the mapping of ones we have already
105  /// processed to the result.
106  std::map<SDOperand, SDOperand> ScalarizedNodes;
107
108  void AddLegalizedOperand(SDOperand From, SDOperand To) {
109    LegalizedNodes.insert(std::make_pair(From, To));
110    // If someone requests legalization of the new node, return itself.
111    if (From != To)
112      LegalizedNodes.insert(std::make_pair(To, To));
113  }
114  void AddPromotedOperand(SDOperand From, SDOperand To) {
115    bool isNew = PromotedNodes.insert(std::make_pair(From, To));
116    assert(isNew && "Got into the map somehow?");
117    // If someone requests legalization of the new node, return itself.
118    LegalizedNodes.insert(std::make_pair(To, To));
119  }
120
121public:
122
123  SelectionDAGLegalize(SelectionDAG &DAG);
124
125  /// getTypeAction - Return how we should legalize values of this type, either
126  /// it is already legal or we need to expand it into multiple registers of
127  /// smaller integer type, or we need to promote it to a larger type.
128  LegalizeAction getTypeAction(MVT::ValueType VT) const {
129    return (LegalizeAction)ValueTypeActions.getTypeAction(VT);
130  }
131
132  /// isTypeLegal - Return true if this type is legal on this target.
133  ///
134  bool isTypeLegal(MVT::ValueType VT) const {
135    return getTypeAction(VT) == Legal;
136  }
137
138  void LegalizeDAG();
139
140private:
141  /// HandleOp - Legalize, Promote, or Expand the specified operand as
142  /// appropriate for its type.
143  void HandleOp(SDOperand Op);
144
145  /// LegalizeOp - We know that the specified value has a legal type.
146  /// Recursively ensure that the operands have legal types, then return the
147  /// result.
148  SDOperand LegalizeOp(SDOperand O);
149
150  /// PromoteOp - Given an operation that produces a value in an invalid type,
151  /// promote it to compute the value into a larger type.  The produced value
152  /// will have the correct bits for the low portion of the register, but no
153  /// guarantee is made about the top bits: it may be zero, sign-extended, or
154  /// garbage.
155  SDOperand PromoteOp(SDOperand O);
156
157  /// ExpandOp - Expand the specified SDOperand into its two component pieces
158  /// Lo&Hi.  Note that the Op MUST be an expanded type.  As a result of this,
159  /// the LegalizeNodes map is filled in for any results that are not expanded,
160  /// the ExpandedNodes map is filled in for any results that are expanded, and
161  /// the Lo/Hi values are returned.   This applies to integer types and Vector
162  /// types.
163  void ExpandOp(SDOperand O, SDOperand &Lo, SDOperand &Hi);
164
165  /// SplitVectorOp - Given an operand of vector type, break it down into
166  /// two smaller values.
167  void SplitVectorOp(SDOperand O, SDOperand &Lo, SDOperand &Hi);
168
169  /// ScalarizeVectorOp - Given an operand of single-element vector type
170  /// (e.g. v1f32), convert it into the equivalent operation that returns a
171  /// scalar (e.g. f32) value.
172  SDOperand ScalarizeVectorOp(SDOperand O);
173
174  /// isShuffleLegal - Return true if a vector shuffle is legal with the
175  /// specified mask and type.  Targets can specify exactly which masks they
176  /// support and the code generator is tasked with not creating illegal masks.
177  ///
178  /// Note that this will also return true for shuffles that are promoted to a
179  /// different type.
180  ///
181  /// If this is a legal shuffle, this method returns the (possibly promoted)
182  /// build_vector Mask.  If it's not a legal shuffle, it returns null.
183  SDNode *isShuffleLegal(MVT::ValueType VT, SDOperand Mask) const;
184
185  bool LegalizeAllNodesNotLeadingTo(SDNode *N, SDNode *Dest,
186                                    SmallPtrSet<SDNode*, 32> &NodesLeadingTo);
187
188  void LegalizeSetCCOperands(SDOperand &LHS, SDOperand &RHS, SDOperand &CC);
189
190  SDOperand CreateStackTemporary(MVT::ValueType VT);
191
192  SDOperand ExpandLibCall(const char *Name, SDNode *Node, bool isSigned,
193                          SDOperand &Hi);
194  SDOperand ExpandIntToFP(bool isSigned, MVT::ValueType DestTy,
195                          SDOperand Source);
196
197  SDOperand ExpandBIT_CONVERT(MVT::ValueType DestVT, SDOperand SrcOp);
198  SDOperand ExpandBUILD_VECTOR(SDNode *Node);
199  SDOperand ExpandSCALAR_TO_VECTOR(SDNode *Node);
200  SDOperand ExpandLegalINT_TO_FP(bool isSigned,
201                                 SDOperand LegalOp,
202                                 MVT::ValueType DestVT);
203  SDOperand PromoteLegalINT_TO_FP(SDOperand LegalOp, MVT::ValueType DestVT,
204                                  bool isSigned);
205  SDOperand PromoteLegalFP_TO_INT(SDOperand LegalOp, MVT::ValueType DestVT,
206                                  bool isSigned);
207
208  SDOperand ExpandBSWAP(SDOperand Op);
209  SDOperand ExpandBitCount(unsigned Opc, SDOperand Op);
210  bool ExpandShift(unsigned Opc, SDOperand Op, SDOperand Amt,
211                   SDOperand &Lo, SDOperand &Hi);
212  void ExpandShiftParts(unsigned NodeOp, SDOperand Op, SDOperand Amt,
213                        SDOperand &Lo, SDOperand &Hi);
214
215  SDOperand ExpandEXTRACT_SUBVECTOR(SDOperand Op);
216  SDOperand ExpandEXTRACT_VECTOR_ELT(SDOperand Op);
217
218  SDOperand getIntPtrConstant(uint64_t Val) {
219    return DAG.getConstant(Val, TLI.getPointerTy());
220  }
221};
222}
223
224/// isVectorShuffleLegal - Return true if a vector shuffle is legal with the
225/// specified mask and type.  Targets can specify exactly which masks they
226/// support and the code generator is tasked with not creating illegal masks.
227///
228/// Note that this will also return true for shuffles that are promoted to a
229/// different type.
230SDNode *SelectionDAGLegalize::isShuffleLegal(MVT::ValueType VT,
231                                             SDOperand Mask) const {
232  switch (TLI.getOperationAction(ISD::VECTOR_SHUFFLE, VT)) {
233  default: return 0;
234  case TargetLowering::Legal:
235  case TargetLowering::Custom:
236    break;
237  case TargetLowering::Promote: {
238    // If this is promoted to a different type, convert the shuffle mask and
239    // ask if it is legal in the promoted type!
240    MVT::ValueType NVT = TLI.getTypeToPromoteTo(ISD::VECTOR_SHUFFLE, VT);
241
242    // If we changed # elements, change the shuffle mask.
243    unsigned NumEltsGrowth =
244      MVT::getVectorNumElements(NVT) / MVT::getVectorNumElements(VT);
245    assert(NumEltsGrowth && "Cannot promote to vector type with fewer elts!");
246    if (NumEltsGrowth > 1) {
247      // Renumber the elements.
248      SmallVector<SDOperand, 8> Ops;
249      for (unsigned i = 0, e = Mask.getNumOperands(); i != e; ++i) {
250        SDOperand InOp = Mask.getOperand(i);
251        for (unsigned j = 0; j != NumEltsGrowth; ++j) {
252          if (InOp.getOpcode() == ISD::UNDEF)
253            Ops.push_back(DAG.getNode(ISD::UNDEF, MVT::i32));
254          else {
255            unsigned InEltNo = cast<ConstantSDNode>(InOp)->getValue();
256            Ops.push_back(DAG.getConstant(InEltNo*NumEltsGrowth+j, MVT::i32));
257          }
258        }
259      }
260      Mask = DAG.getNode(ISD::BUILD_VECTOR, NVT, &Ops[0], Ops.size());
261    }
262    VT = NVT;
263    break;
264  }
265  }
266  return TLI.isShuffleMaskLegal(Mask, VT) ? Mask.Val : 0;
267}
268
269SelectionDAGLegalize::SelectionDAGLegalize(SelectionDAG &dag)
270  : TLI(dag.getTargetLoweringInfo()), DAG(dag),
271    ValueTypeActions(TLI.getValueTypeActions()) {
272  assert(MVT::LAST_VALUETYPE <= 32 &&
273         "Too many value types for ValueTypeActions to hold!");
274}
275
276/// ComputeTopDownOrdering - Compute a top-down ordering of the dag, where Order
277/// contains all of a nodes operands before it contains the node.
278static void ComputeTopDownOrdering(SelectionDAG &DAG,
279                                   SmallVector<SDNode*, 64> &Order) {
280
281  DenseMap<SDNode*, unsigned> Visited;
282  std::vector<SDNode*> Worklist;
283  Worklist.reserve(128);
284
285  // Compute ordering from all of the leaves in the graphs, those (like the
286  // entry node) that have no operands.
287  for (SelectionDAG::allnodes_iterator I = DAG.allnodes_begin(),
288       E = DAG.allnodes_end(); I != E; ++I) {
289    if (I->getNumOperands() == 0) {
290      Visited[I] = 0 - 1U;
291      Worklist.push_back(I);
292    }
293  }
294
295  while (!Worklist.empty()) {
296    SDNode *N = Worklist.back();
297    Worklist.pop_back();
298
299    if (++Visited[N] != N->getNumOperands())
300      continue;  // Haven't visited all operands yet
301
302    Order.push_back(N);
303
304    // Now that we have N in, add anything that uses it if all of their operands
305    // are now done.
306    for (SDNode::use_iterator UI = N->use_begin(), E = N->use_end();
307         UI != E; ++UI)
308      Worklist.push_back(*UI);
309  }
310
311  assert(Order.size() == Visited.size() &&
312         Order.size() ==
313         (unsigned)std::distance(DAG.allnodes_begin(), DAG.allnodes_end()) &&
314         "Error: DAG is cyclic!");
315}
316
317
318void SelectionDAGLegalize::LegalizeDAG() {
319  LastCALLSEQ_END = DAG.getEntryNode();
320  IsLegalizingCall = false;
321
322  // The legalize process is inherently a bottom-up recursive process (users
323  // legalize their uses before themselves).  Given infinite stack space, we
324  // could just start legalizing on the root and traverse the whole graph.  In
325  // practice however, this causes us to run out of stack space on large basic
326  // blocks.  To avoid this problem, compute an ordering of the nodes where each
327  // node is only legalized after all of its operands are legalized.
328  SmallVector<SDNode*, 64> Order;
329  ComputeTopDownOrdering(DAG, Order);
330
331  for (unsigned i = 0, e = Order.size(); i != e; ++i)
332    HandleOp(SDOperand(Order[i], 0));
333
334  // Finally, it's possible the root changed.  Get the new root.
335  SDOperand OldRoot = DAG.getRoot();
336  assert(LegalizedNodes.count(OldRoot) && "Root didn't get legalized?");
337  DAG.setRoot(LegalizedNodes[OldRoot]);
338
339  ExpandedNodes.clear();
340  LegalizedNodes.clear();
341  PromotedNodes.clear();
342  SplitNodes.clear();
343  ScalarizedNodes.clear();
344
345  // Remove dead nodes now.
346  DAG.RemoveDeadNodes();
347}
348
349
350/// FindCallEndFromCallStart - Given a chained node that is part of a call
351/// sequence, find the CALLSEQ_END node that terminates the call sequence.
352static SDNode *FindCallEndFromCallStart(SDNode *Node) {
353  if (Node->getOpcode() == ISD::CALLSEQ_END)
354    return Node;
355  if (Node->use_empty())
356    return 0;   // No CallSeqEnd
357
358  // The chain is usually at the end.
359  SDOperand TheChain(Node, Node->getNumValues()-1);
360  if (TheChain.getValueType() != MVT::Other) {
361    // Sometimes it's at the beginning.
362    TheChain = SDOperand(Node, 0);
363    if (TheChain.getValueType() != MVT::Other) {
364      // Otherwise, hunt for it.
365      for (unsigned i = 1, e = Node->getNumValues(); i != e; ++i)
366        if (Node->getValueType(i) == MVT::Other) {
367          TheChain = SDOperand(Node, i);
368          break;
369        }
370
371      // Otherwise, we walked into a node without a chain.
372      if (TheChain.getValueType() != MVT::Other)
373        return 0;
374    }
375  }
376
377  for (SDNode::use_iterator UI = Node->use_begin(),
378       E = Node->use_end(); UI != E; ++UI) {
379
380    // Make sure to only follow users of our token chain.
381    SDNode *User = *UI;
382    for (unsigned i = 0, e = User->getNumOperands(); i != e; ++i)
383      if (User->getOperand(i) == TheChain)
384        if (SDNode *Result = FindCallEndFromCallStart(User))
385          return Result;
386  }
387  return 0;
388}
389
390/// FindCallStartFromCallEnd - Given a chained node that is part of a call
391/// sequence, find the CALLSEQ_START node that initiates the call sequence.
392static SDNode *FindCallStartFromCallEnd(SDNode *Node) {
393  assert(Node && "Didn't find callseq_start for a call??");
394  if (Node->getOpcode() == ISD::CALLSEQ_START) return Node;
395
396  assert(Node->getOperand(0).getValueType() == MVT::Other &&
397         "Node doesn't have a token chain argument!");
398  return FindCallStartFromCallEnd(Node->getOperand(0).Val);
399}
400
401/// LegalizeAllNodesNotLeadingTo - Recursively walk the uses of N, looking to
402/// see if any uses can reach Dest.  If no dest operands can get to dest,
403/// legalize them, legalize ourself, and return false, otherwise, return true.
404///
405/// Keep track of the nodes we fine that actually do lead to Dest in
406/// NodesLeadingTo.  This avoids retraversing them exponential number of times.
407///
408bool SelectionDAGLegalize::LegalizeAllNodesNotLeadingTo(SDNode *N, SDNode *Dest,
409                                     SmallPtrSet<SDNode*, 32> &NodesLeadingTo) {
410  if (N == Dest) return true;  // N certainly leads to Dest :)
411
412  // If we've already processed this node and it does lead to Dest, there is no
413  // need to reprocess it.
414  if (NodesLeadingTo.count(N)) return true;
415
416  // If the first result of this node has been already legalized, then it cannot
417  // reach N.
418  switch (getTypeAction(N->getValueType(0))) {
419  case Legal:
420    if (LegalizedNodes.count(SDOperand(N, 0))) return false;
421    break;
422  case Promote:
423    if (PromotedNodes.count(SDOperand(N, 0))) return false;
424    break;
425  case Expand:
426    if (ExpandedNodes.count(SDOperand(N, 0))) return false;
427    break;
428  }
429
430  // Okay, this node has not already been legalized.  Check and legalize all
431  // operands.  If none lead to Dest, then we can legalize this node.
432  bool OperandsLeadToDest = false;
433  for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
434    OperandsLeadToDest |=     // If an operand leads to Dest, so do we.
435      LegalizeAllNodesNotLeadingTo(N->getOperand(i).Val, Dest, NodesLeadingTo);
436
437  if (OperandsLeadToDest) {
438    NodesLeadingTo.insert(N);
439    return true;
440  }
441
442  // Okay, this node looks safe, legalize it and return false.
443  HandleOp(SDOperand(N, 0));
444  return false;
445}
446
447/// HandleOp - Legalize, Promote, or Expand the specified operand as
448/// appropriate for its type.
449void SelectionDAGLegalize::HandleOp(SDOperand Op) {
450  MVT::ValueType VT = Op.getValueType();
451  switch (getTypeAction(VT)) {
452  default: assert(0 && "Bad type action!");
453  case Legal:   (void)LegalizeOp(Op); break;
454  case Promote: (void)PromoteOp(Op); break;
455  case Expand:
456    if (!MVT::isVector(VT)) {
457      // If this is an illegal scalar, expand it into its two component
458      // pieces.
459      SDOperand X, Y;
460      if (Op.getOpcode() == ISD::TargetConstant)
461        break;  // Allow illegal target nodes.
462      ExpandOp(Op, X, Y);
463    } else if (MVT::getVectorNumElements(VT) == 1) {
464      // If this is an illegal single element vector, convert it to a
465      // scalar operation.
466      (void)ScalarizeVectorOp(Op);
467    } else {
468      // Otherwise, this is an illegal multiple element vector.
469      // Split it in half and legalize both parts.
470      SDOperand X, Y;
471      SplitVectorOp(Op, X, Y);
472    }
473    break;
474  }
475}
476
477/// ExpandConstantFP - Expands the ConstantFP node to an integer constant or
478/// a load from the constant pool.
479static SDOperand ExpandConstantFP(ConstantFPSDNode *CFP, bool UseCP,
480                                  SelectionDAG &DAG, TargetLowering &TLI) {
481  bool Extend = false;
482
483  // If a FP immediate is precise when represented as a float and if the
484  // target can do an extending load from float to double, we put it into
485  // the constant pool as a float, even if it's is statically typed as a
486  // double.
487  MVT::ValueType VT = CFP->getValueType(0);
488  bool isDouble = VT == MVT::f64;
489  ConstantFP *LLVMC = ConstantFP::get(MVT::getTypeForValueType(VT),
490                                      CFP->getValueAPF());
491  if (!UseCP) {
492    if (VT!=MVT::f64 && VT!=MVT::f32)
493      assert(0 && "Invalid type expansion");
494    return DAG.getConstant(LLVMC->getValueAPF().convertToAPInt().getZExtValue(),
495                           isDouble ? MVT::i64 : MVT::i32);
496  }
497
498  if (isDouble && CFP->isValueValidForType(MVT::f32, CFP->getValueAPF()) &&
499      // Only do this if the target has a native EXTLOAD instruction from f32.
500      // Do not try to be clever about long doubles (so far)
501      TLI.isLoadXLegal(ISD::EXTLOAD, MVT::f32)) {
502    LLVMC = cast<ConstantFP>(ConstantExpr::getFPTrunc(LLVMC,Type::FloatTy));
503    VT = MVT::f32;
504    Extend = true;
505  }
506
507  SDOperand CPIdx = DAG.getConstantPool(LLVMC, TLI.getPointerTy());
508  if (Extend) {
509    return DAG.getExtLoad(ISD::EXTLOAD, MVT::f64, DAG.getEntryNode(),
510                          CPIdx, NULL, 0, MVT::f32);
511  } else {
512    return DAG.getLoad(VT, DAG.getEntryNode(), CPIdx, NULL, 0);
513  }
514}
515
516
517/// ExpandFCOPYSIGNToBitwiseOps - Expands fcopysign to a series of bitwise
518/// operations.
519static
520SDOperand ExpandFCOPYSIGNToBitwiseOps(SDNode *Node, MVT::ValueType NVT,
521                                      SelectionDAG &DAG, TargetLowering &TLI) {
522  MVT::ValueType VT = Node->getValueType(0);
523  MVT::ValueType SrcVT = Node->getOperand(1).getValueType();
524  assert((SrcVT == MVT::f32 || SrcVT == MVT::f64) &&
525         "fcopysign expansion only supported for f32 and f64");
526  MVT::ValueType SrcNVT = (SrcVT == MVT::f64) ? MVT::i64 : MVT::i32;
527
528  // First get the sign bit of second operand.
529  SDOperand Mask1 = (SrcVT == MVT::f64)
530    ? DAG.getConstantFP(BitsToDouble(1ULL << 63), SrcVT)
531    : DAG.getConstantFP(BitsToFloat(1U << 31), SrcVT);
532  Mask1 = DAG.getNode(ISD::BIT_CONVERT, SrcNVT, Mask1);
533  SDOperand SignBit= DAG.getNode(ISD::BIT_CONVERT, SrcNVT, Node->getOperand(1));
534  SignBit = DAG.getNode(ISD::AND, SrcNVT, SignBit, Mask1);
535  // Shift right or sign-extend it if the two operands have different types.
536  int SizeDiff = MVT::getSizeInBits(SrcNVT) - MVT::getSizeInBits(NVT);
537  if (SizeDiff > 0) {
538    SignBit = DAG.getNode(ISD::SRL, SrcNVT, SignBit,
539                          DAG.getConstant(SizeDiff, TLI.getShiftAmountTy()));
540    SignBit = DAG.getNode(ISD::TRUNCATE, NVT, SignBit);
541  } else if (SizeDiff < 0)
542    SignBit = DAG.getNode(ISD::SIGN_EXTEND, NVT, SignBit);
543
544  // Clear the sign bit of first operand.
545  SDOperand Mask2 = (VT == MVT::f64)
546    ? DAG.getConstantFP(BitsToDouble(~(1ULL << 63)), VT)
547    : DAG.getConstantFP(BitsToFloat(~(1U << 31)), VT);
548  Mask2 = DAG.getNode(ISD::BIT_CONVERT, NVT, Mask2);
549  SDOperand Result = DAG.getNode(ISD::BIT_CONVERT, NVT, Node->getOperand(0));
550  Result = DAG.getNode(ISD::AND, NVT, Result, Mask2);
551
552  // Or the value with the sign bit.
553  Result = DAG.getNode(ISD::OR, NVT, Result, SignBit);
554  return Result;
555}
556
557/// ExpandUnalignedStore - Expands an unaligned store to 2 half-size stores.
558static
559SDOperand ExpandUnalignedStore(StoreSDNode *ST, SelectionDAG &DAG,
560                               TargetLowering &TLI) {
561  SDOperand Chain = ST->getChain();
562  SDOperand Ptr = ST->getBasePtr();
563  SDOperand Val = ST->getValue();
564  MVT::ValueType VT = Val.getValueType();
565  int Alignment = ST->getAlignment();
566  int SVOffset = ST->getSrcValueOffset();
567  if (MVT::isFloatingPoint(ST->getStoredVT())) {
568    // Expand to a bitconvert of the value to the integer type of the
569    // same size, then a (misaligned) int store.
570    MVT::ValueType intVT;
571    if (VT==MVT::f64)
572      intVT = MVT::i64;
573    else if (VT==MVT::f32)
574      intVT = MVT::i32;
575    else
576      assert(0 && "Unaligned load of unsupported floating point type");
577
578    SDOperand Result = DAG.getNode(ISD::BIT_CONVERT, intVT, Val);
579    return DAG.getStore(Chain, Result, Ptr, ST->getSrcValue(),
580                        SVOffset, ST->isVolatile(), Alignment);
581  }
582  assert(MVT::isInteger(ST->getStoredVT()) &&
583         "Unaligned store of unknown type.");
584  // Get the half-size VT
585  MVT::ValueType NewStoredVT = ST->getStoredVT() - 1;
586  int NumBits = MVT::getSizeInBits(NewStoredVT);
587  int IncrementSize = NumBits / 8;
588
589  // Divide the stored value in two parts.
590  SDOperand ShiftAmount = DAG.getConstant(NumBits, TLI.getShiftAmountTy());
591  SDOperand Lo = Val;
592  SDOperand Hi = DAG.getNode(ISD::SRL, VT, Val, ShiftAmount);
593
594  // Store the two parts
595  SDOperand Store1, Store2;
596  Store1 = DAG.getTruncStore(Chain, TLI.isLittleEndian()?Lo:Hi, Ptr,
597                             ST->getSrcValue(), SVOffset, NewStoredVT,
598                             ST->isVolatile(), Alignment);
599  Ptr = DAG.getNode(ISD::ADD, Ptr.getValueType(), Ptr,
600                    DAG.getConstant(IncrementSize, TLI.getPointerTy()));
601  Store2 = DAG.getTruncStore(Chain, TLI.isLittleEndian()?Hi:Lo, Ptr,
602                             ST->getSrcValue(), SVOffset + IncrementSize,
603                             NewStoredVT, ST->isVolatile(), Alignment);
604
605  return DAG.getNode(ISD::TokenFactor, MVT::Other, Store1, Store2);
606}
607
608/// ExpandUnalignedLoad - Expands an unaligned load to 2 half-size loads.
609static
610SDOperand ExpandUnalignedLoad(LoadSDNode *LD, SelectionDAG &DAG,
611                              TargetLowering &TLI) {
612  int SVOffset = LD->getSrcValueOffset();
613  SDOperand Chain = LD->getChain();
614  SDOperand Ptr = LD->getBasePtr();
615  MVT::ValueType VT = LD->getValueType(0);
616  MVT::ValueType LoadedVT = LD->getLoadedVT();
617  if (MVT::isFloatingPoint(VT)) {
618    // Expand to a (misaligned) integer load of the same size,
619    // then bitconvert to floating point.
620    MVT::ValueType intVT;
621    if (LoadedVT==MVT::f64)
622      intVT = MVT::i64;
623    else if (LoadedVT==MVT::f32)
624      intVT = MVT::i32;
625    else
626      assert(0 && "Unaligned load of unsupported floating point type");
627
628    SDOperand newLoad = DAG.getLoad(intVT, Chain, Ptr, LD->getSrcValue(),
629                                    SVOffset, LD->isVolatile(),
630                                    LD->getAlignment());
631    SDOperand Result = DAG.getNode(ISD::BIT_CONVERT, LoadedVT, newLoad);
632    if (LoadedVT != VT)
633      Result = DAG.getNode(ISD::FP_EXTEND, VT, Result);
634
635    SDOperand Ops[] = { Result, Chain };
636    return DAG.getNode(ISD::MERGE_VALUES, DAG.getVTList(VT, MVT::Other),
637                       Ops, 2);
638  }
639  assert(MVT::isInteger(LoadedVT) && "Unaligned load of unsupported type.");
640  MVT::ValueType NewLoadedVT = LoadedVT - 1;
641  int NumBits = MVT::getSizeInBits(NewLoadedVT);
642  int Alignment = LD->getAlignment();
643  int IncrementSize = NumBits / 8;
644  ISD::LoadExtType HiExtType = LD->getExtensionType();
645
646  // If the original load is NON_EXTLOAD, the hi part load must be ZEXTLOAD.
647  if (HiExtType == ISD::NON_EXTLOAD)
648    HiExtType = ISD::ZEXTLOAD;
649
650  // Load the value in two parts
651  SDOperand Lo, Hi;
652  if (TLI.isLittleEndian()) {
653    Lo = DAG.getExtLoad(ISD::ZEXTLOAD, VT, Chain, Ptr, LD->getSrcValue(),
654                        SVOffset, NewLoadedVT, LD->isVolatile(), Alignment);
655    Ptr = DAG.getNode(ISD::ADD, Ptr.getValueType(), Ptr,
656                      DAG.getConstant(IncrementSize, TLI.getPointerTy()));
657    Hi = DAG.getExtLoad(HiExtType, VT, Chain, Ptr, LD->getSrcValue(),
658                        SVOffset + IncrementSize, NewLoadedVT, LD->isVolatile(),
659                        Alignment);
660  } else {
661    Hi = DAG.getExtLoad(HiExtType, VT, Chain, Ptr, LD->getSrcValue(), SVOffset,
662                        NewLoadedVT,LD->isVolatile(), Alignment);
663    Ptr = DAG.getNode(ISD::ADD, Ptr.getValueType(), Ptr,
664                      DAG.getConstant(IncrementSize, TLI.getPointerTy()));
665    Lo = DAG.getExtLoad(ISD::ZEXTLOAD, VT, Chain, Ptr, LD->getSrcValue(),
666                        SVOffset + IncrementSize, NewLoadedVT, LD->isVolatile(),
667                        Alignment);
668  }
669
670  // aggregate the two parts
671  SDOperand ShiftAmount = DAG.getConstant(NumBits, TLI.getShiftAmountTy());
672  SDOperand Result = DAG.getNode(ISD::SHL, VT, Hi, ShiftAmount);
673  Result = DAG.getNode(ISD::OR, VT, Result, Lo);
674
675  SDOperand TF = DAG.getNode(ISD::TokenFactor, MVT::Other, Lo.getValue(1),
676                             Hi.getValue(1));
677
678  SDOperand Ops[] = { Result, TF };
679  return DAG.getNode(ISD::MERGE_VALUES, DAG.getVTList(VT, MVT::Other), Ops, 2);
680}
681
682/// LegalizeOp - We know that the specified value has a legal type, and
683/// that its operands are legal.  Now ensure that the operation itself
684/// is legal, recursively ensuring that the operands' operations remain
685/// legal.
686SDOperand SelectionDAGLegalize::LegalizeOp(SDOperand Op) {
687  if (Op.getOpcode() == ISD::TargetConstant) // Allow illegal target nodes.
688    return Op;
689
690  assert(isTypeLegal(Op.getValueType()) &&
691         "Caller should expand or promote operands that are not legal!");
692  SDNode *Node = Op.Val;
693
694  // If this operation defines any values that cannot be represented in a
695  // register on this target, make sure to expand or promote them.
696  if (Node->getNumValues() > 1) {
697    for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
698      if (getTypeAction(Node->getValueType(i)) != Legal) {
699        HandleOp(Op.getValue(i));
700        assert(LegalizedNodes.count(Op) &&
701               "Handling didn't add legal operands!");
702        return LegalizedNodes[Op];
703      }
704  }
705
706  // Note that LegalizeOp may be reentered even from single-use nodes, which
707  // means that we always must cache transformed nodes.
708  DenseMap<SDOperand, SDOperand>::iterator I = LegalizedNodes.find(Op);
709  if (I != LegalizedNodes.end()) return I->second;
710
711  SDOperand Tmp1, Tmp2, Tmp3, Tmp4;
712  SDOperand Result = Op;
713  bool isCustom = false;
714
715  switch (Node->getOpcode()) {
716  case ISD::FrameIndex:
717  case ISD::EntryToken:
718  case ISD::Register:
719  case ISD::BasicBlock:
720  case ISD::TargetFrameIndex:
721  case ISD::TargetJumpTable:
722  case ISD::TargetConstant:
723  case ISD::TargetConstantFP:
724  case ISD::TargetConstantPool:
725  case ISD::TargetGlobalAddress:
726  case ISD::TargetGlobalTLSAddress:
727  case ISD::TargetExternalSymbol:
728  case ISD::VALUETYPE:
729  case ISD::SRCVALUE:
730  case ISD::STRING:
731  case ISD::CONDCODE:
732    // Primitives must all be legal.
733    assert(TLI.isOperationLegal(Node->getValueType(0), Node->getValueType(0)) &&
734           "This must be legal!");
735    break;
736  default:
737    if (Node->getOpcode() >= ISD::BUILTIN_OP_END) {
738      // If this is a target node, legalize it by legalizing the operands then
739      // passing it through.
740      SmallVector<SDOperand, 8> Ops;
741      for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i)
742        Ops.push_back(LegalizeOp(Node->getOperand(i)));
743
744      Result = DAG.UpdateNodeOperands(Result.getValue(0), &Ops[0], Ops.size());
745
746      for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
747        AddLegalizedOperand(Op.getValue(i), Result.getValue(i));
748      return Result.getValue(Op.ResNo);
749    }
750    // Otherwise this is an unhandled builtin node.  splat.
751#ifndef NDEBUG
752    cerr << "NODE: "; Node->dump(&DAG); cerr << "\n";
753#endif
754    assert(0 && "Do not know how to legalize this operator!");
755    abort();
756  case ISD::GLOBAL_OFFSET_TABLE:
757  case ISD::GlobalAddress:
758  case ISD::GlobalTLSAddress:
759  case ISD::ExternalSymbol:
760  case ISD::ConstantPool:
761  case ISD::JumpTable: // Nothing to do.
762    switch (TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0))) {
763    default: assert(0 && "This action is not supported yet!");
764    case TargetLowering::Custom:
765      Tmp1 = TLI.LowerOperation(Op, DAG);
766      if (Tmp1.Val) Result = Tmp1;
767      // FALLTHROUGH if the target doesn't want to lower this op after all.
768    case TargetLowering::Legal:
769      break;
770    }
771    break;
772  case ISD::FRAMEADDR:
773  case ISD::RETURNADDR:
774    // The only option for these nodes is to custom lower them.  If the target
775    // does not custom lower them, then return zero.
776    Tmp1 = TLI.LowerOperation(Op, DAG);
777    if (Tmp1.Val)
778      Result = Tmp1;
779    else
780      Result = DAG.getConstant(0, TLI.getPointerTy());
781    break;
782  case ISD::FRAME_TO_ARGS_OFFSET: {
783    MVT::ValueType VT = Node->getValueType(0);
784    switch (TLI.getOperationAction(Node->getOpcode(), VT)) {
785    default: assert(0 && "This action is not supported yet!");
786    case TargetLowering::Custom:
787      Result = TLI.LowerOperation(Op, DAG);
788      if (Result.Val) break;
789      // Fall Thru
790    case TargetLowering::Legal:
791      Result = DAG.getConstant(0, VT);
792      break;
793    }
794    }
795    break;
796  case ISD::EXCEPTIONADDR: {
797    Tmp1 = LegalizeOp(Node->getOperand(0));
798    MVT::ValueType VT = Node->getValueType(0);
799    switch (TLI.getOperationAction(Node->getOpcode(), VT)) {
800    default: assert(0 && "This action is not supported yet!");
801    case TargetLowering::Expand: {
802        unsigned Reg = TLI.getExceptionAddressRegister();
803        Result = DAG.getCopyFromReg(Tmp1, Reg, VT).getValue(Op.ResNo);
804      }
805      break;
806    case TargetLowering::Custom:
807      Result = TLI.LowerOperation(Op, DAG);
808      if (Result.Val) break;
809      // Fall Thru
810    case TargetLowering::Legal: {
811      SDOperand Ops[] = { DAG.getConstant(0, VT), Tmp1 };
812      Result = DAG.getNode(ISD::MERGE_VALUES, DAG.getVTList(VT, MVT::Other),
813                           Ops, 2).getValue(Op.ResNo);
814      break;
815    }
816    }
817    }
818    break;
819  case ISD::EHSELECTION: {
820    Tmp1 = LegalizeOp(Node->getOperand(0));
821    Tmp2 = LegalizeOp(Node->getOperand(1));
822    MVT::ValueType VT = Node->getValueType(0);
823    switch (TLI.getOperationAction(Node->getOpcode(), VT)) {
824    default: assert(0 && "This action is not supported yet!");
825    case TargetLowering::Expand: {
826        unsigned Reg = TLI.getExceptionSelectorRegister();
827        Result = DAG.getCopyFromReg(Tmp2, Reg, VT).getValue(Op.ResNo);
828      }
829      break;
830    case TargetLowering::Custom:
831      Result = TLI.LowerOperation(Op, DAG);
832      if (Result.Val) break;
833      // Fall Thru
834    case TargetLowering::Legal: {
835      SDOperand Ops[] = { DAG.getConstant(0, VT), Tmp2 };
836      Result = DAG.getNode(ISD::MERGE_VALUES, DAG.getVTList(VT, MVT::Other),
837                           Ops, 2).getValue(Op.ResNo);
838      break;
839    }
840    }
841    }
842    break;
843  case ISD::EH_RETURN: {
844    MVT::ValueType VT = Node->getValueType(0);
845    // The only "good" option for this node is to custom lower it.
846    switch (TLI.getOperationAction(Node->getOpcode(), VT)) {
847    default: assert(0 && "This action is not supported at all!");
848    case TargetLowering::Custom:
849      Result = TLI.LowerOperation(Op, DAG);
850      if (Result.Val) break;
851      // Fall Thru
852    case TargetLowering::Legal:
853      // Target does not know, how to lower this, lower to noop
854      Result = LegalizeOp(Node->getOperand(0));
855      break;
856    }
857    }
858    break;
859  case ISD::AssertSext:
860  case ISD::AssertZext:
861    Tmp1 = LegalizeOp(Node->getOperand(0));
862    Result = DAG.UpdateNodeOperands(Result, Tmp1, Node->getOperand(1));
863    break;
864  case ISD::MERGE_VALUES:
865    // Legalize eliminates MERGE_VALUES nodes.
866    Result = Node->getOperand(Op.ResNo);
867    break;
868  case ISD::CopyFromReg:
869    Tmp1 = LegalizeOp(Node->getOperand(0));
870    Result = Op.getValue(0);
871    if (Node->getNumValues() == 2) {
872      Result = DAG.UpdateNodeOperands(Result, Tmp1, Node->getOperand(1));
873    } else {
874      assert(Node->getNumValues() == 3 && "Invalid copyfromreg!");
875      if (Node->getNumOperands() == 3) {
876        Tmp2 = LegalizeOp(Node->getOperand(2));
877        Result = DAG.UpdateNodeOperands(Result, Tmp1, Node->getOperand(1),Tmp2);
878      } else {
879        Result = DAG.UpdateNodeOperands(Result, Tmp1, Node->getOperand(1));
880      }
881      AddLegalizedOperand(Op.getValue(2), Result.getValue(2));
882    }
883    // Since CopyFromReg produces two values, make sure to remember that we
884    // legalized both of them.
885    AddLegalizedOperand(Op.getValue(0), Result);
886    AddLegalizedOperand(Op.getValue(1), Result.getValue(1));
887    return Result.getValue(Op.ResNo);
888  case ISD::UNDEF: {
889    MVT::ValueType VT = Op.getValueType();
890    switch (TLI.getOperationAction(ISD::UNDEF, VT)) {
891    default: assert(0 && "This action is not supported yet!");
892    case TargetLowering::Expand:
893      if (MVT::isInteger(VT))
894        Result = DAG.getConstant(0, VT);
895      else if (MVT::isFloatingPoint(VT))
896        Result = DAG.getConstantFP(0, VT);
897      else
898        assert(0 && "Unknown value type!");
899      break;
900    case TargetLowering::Legal:
901      break;
902    }
903    break;
904  }
905
906  case ISD::INTRINSIC_W_CHAIN:
907  case ISD::INTRINSIC_WO_CHAIN:
908  case ISD::INTRINSIC_VOID: {
909    SmallVector<SDOperand, 8> Ops;
910    for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i)
911      Ops.push_back(LegalizeOp(Node->getOperand(i)));
912    Result = DAG.UpdateNodeOperands(Result, &Ops[0], Ops.size());
913
914    // Allow the target to custom lower its intrinsics if it wants to.
915    if (TLI.getOperationAction(Node->getOpcode(), MVT::Other) ==
916        TargetLowering::Custom) {
917      Tmp3 = TLI.LowerOperation(Result, DAG);
918      if (Tmp3.Val) Result = Tmp3;
919    }
920
921    if (Result.Val->getNumValues() == 1) break;
922
923    // Must have return value and chain result.
924    assert(Result.Val->getNumValues() == 2 &&
925           "Cannot return more than two values!");
926
927    // Since loads produce two values, make sure to remember that we
928    // legalized both of them.
929    AddLegalizedOperand(SDOperand(Node, 0), Result.getValue(0));
930    AddLegalizedOperand(SDOperand(Node, 1), Result.getValue(1));
931    return Result.getValue(Op.ResNo);
932  }
933
934  case ISD::LOCATION:
935    assert(Node->getNumOperands() == 5 && "Invalid LOCATION node!");
936    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the input chain.
937
938    switch (TLI.getOperationAction(ISD::LOCATION, MVT::Other)) {
939    case TargetLowering::Promote:
940    default: assert(0 && "This action is not supported yet!");
941    case TargetLowering::Expand: {
942      MachineModuleInfo *MMI = DAG.getMachineModuleInfo();
943      bool useDEBUG_LOC = TLI.isOperationLegal(ISD::DEBUG_LOC, MVT::Other);
944      bool useLABEL = TLI.isOperationLegal(ISD::LABEL, MVT::Other);
945
946      if (MMI && (useDEBUG_LOC || useLABEL)) {
947        const std::string &FName =
948          cast<StringSDNode>(Node->getOperand(3))->getValue();
949        const std::string &DirName =
950          cast<StringSDNode>(Node->getOperand(4))->getValue();
951        unsigned SrcFile = MMI->RecordSource(DirName, FName);
952
953        SmallVector<SDOperand, 8> Ops;
954        Ops.push_back(Tmp1);  // chain
955        SDOperand LineOp = Node->getOperand(1);
956        SDOperand ColOp = Node->getOperand(2);
957
958        if (useDEBUG_LOC) {
959          Ops.push_back(LineOp);  // line #
960          Ops.push_back(ColOp);  // col #
961          Ops.push_back(DAG.getConstant(SrcFile, MVT::i32));  // source file id
962          Result = DAG.getNode(ISD::DEBUG_LOC, MVT::Other, &Ops[0], Ops.size());
963        } else {
964          unsigned Line = cast<ConstantSDNode>(LineOp)->getValue();
965          unsigned Col = cast<ConstantSDNode>(ColOp)->getValue();
966          unsigned ID = MMI->RecordLabel(Line, Col, SrcFile);
967          Ops.push_back(DAG.getConstant(ID, MVT::i32));
968          Result = DAG.getNode(ISD::LABEL, MVT::Other,&Ops[0],Ops.size());
969        }
970      } else {
971        Result = Tmp1;  // chain
972      }
973      break;
974    }
975    case TargetLowering::Legal:
976      if (Tmp1 != Node->getOperand(0) ||
977          getTypeAction(Node->getOperand(1).getValueType()) == Promote) {
978        SmallVector<SDOperand, 8> Ops;
979        Ops.push_back(Tmp1);
980        if (getTypeAction(Node->getOperand(1).getValueType()) == Legal) {
981          Ops.push_back(Node->getOperand(1));  // line # must be legal.
982          Ops.push_back(Node->getOperand(2));  // col # must be legal.
983        } else {
984          // Otherwise promote them.
985          Ops.push_back(PromoteOp(Node->getOperand(1)));
986          Ops.push_back(PromoteOp(Node->getOperand(2)));
987        }
988        Ops.push_back(Node->getOperand(3));  // filename must be legal.
989        Ops.push_back(Node->getOperand(4));  // working dir # must be legal.
990        Result = DAG.UpdateNodeOperands(Result, &Ops[0], Ops.size());
991      }
992      break;
993    }
994    break;
995
996  case ISD::DEBUG_LOC:
997    assert(Node->getNumOperands() == 4 && "Invalid DEBUG_LOC node!");
998    switch (TLI.getOperationAction(ISD::DEBUG_LOC, MVT::Other)) {
999    default: assert(0 && "This action is not supported yet!");
1000    case TargetLowering::Legal:
1001      Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
1002      Tmp2 = LegalizeOp(Node->getOperand(1));  // Legalize the line #.
1003      Tmp3 = LegalizeOp(Node->getOperand(2));  // Legalize the col #.
1004      Tmp4 = LegalizeOp(Node->getOperand(3));  // Legalize the source file id.
1005      Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3, Tmp4);
1006      break;
1007    }
1008    break;
1009
1010  case ISD::LABEL:
1011    assert(Node->getNumOperands() == 2 && "Invalid LABEL node!");
1012    switch (TLI.getOperationAction(ISD::LABEL, MVT::Other)) {
1013    default: assert(0 && "This action is not supported yet!");
1014    case TargetLowering::Legal:
1015      Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
1016      Tmp2 = LegalizeOp(Node->getOperand(1));  // Legalize the label id.
1017      Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2);
1018      break;
1019    case TargetLowering::Expand:
1020      Result = LegalizeOp(Node->getOperand(0));
1021      break;
1022    }
1023    break;
1024
1025  case ISD::Constant: {
1026    ConstantSDNode *CN = cast<ConstantSDNode>(Node);
1027    unsigned opAction =
1028      TLI.getOperationAction(ISD::Constant, CN->getValueType(0));
1029
1030    // We know we don't need to expand constants here, constants only have one
1031    // value and we check that it is fine above.
1032
1033    if (opAction == TargetLowering::Custom) {
1034      Tmp1 = TLI.LowerOperation(Result, DAG);
1035      if (Tmp1.Val)
1036        Result = Tmp1;
1037    }
1038    break;
1039  }
1040  case ISD::ConstantFP: {
1041    // Spill FP immediates to the constant pool if the target cannot directly
1042    // codegen them.  Targets often have some immediate values that can be
1043    // efficiently generated into an FP register without a load.  We explicitly
1044    // leave these constants as ConstantFP nodes for the target to deal with.
1045    ConstantFPSDNode *CFP = cast<ConstantFPSDNode>(Node);
1046
1047    // Check to see if this FP immediate is already legal.
1048    bool isLegal = false;
1049    for (TargetLowering::legal_fpimm_iterator I = TLI.legal_fpimm_begin(),
1050           E = TLI.legal_fpimm_end(); I != E; ++I)
1051      if (CFP->isExactlyValue(*I)) {
1052        isLegal = true;
1053        break;
1054      }
1055
1056    // If this is a legal constant, turn it into a TargetConstantFP node.
1057    if (isLegal) {
1058      Result = DAG.getTargetConstantFP(CFP->getValueAPF(),
1059                                       CFP->getValueType(0));
1060      break;
1061    }
1062
1063    switch (TLI.getOperationAction(ISD::ConstantFP, CFP->getValueType(0))) {
1064    default: assert(0 && "This action is not supported yet!");
1065    case TargetLowering::Custom:
1066      Tmp3 = TLI.LowerOperation(Result, DAG);
1067      if (Tmp3.Val) {
1068        Result = Tmp3;
1069        break;
1070      }
1071      // FALLTHROUGH
1072    case TargetLowering::Expand:
1073      Result = ExpandConstantFP(CFP, true, DAG, TLI);
1074    }
1075    break;
1076  }
1077  case ISD::TokenFactor:
1078    if (Node->getNumOperands() == 2) {
1079      Tmp1 = LegalizeOp(Node->getOperand(0));
1080      Tmp2 = LegalizeOp(Node->getOperand(1));
1081      Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2);
1082    } else if (Node->getNumOperands() == 3) {
1083      Tmp1 = LegalizeOp(Node->getOperand(0));
1084      Tmp2 = LegalizeOp(Node->getOperand(1));
1085      Tmp3 = LegalizeOp(Node->getOperand(2));
1086      Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3);
1087    } else {
1088      SmallVector<SDOperand, 8> Ops;
1089      // Legalize the operands.
1090      for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i)
1091        Ops.push_back(LegalizeOp(Node->getOperand(i)));
1092      Result = DAG.UpdateNodeOperands(Result, &Ops[0], Ops.size());
1093    }
1094    break;
1095
1096  case ISD::FORMAL_ARGUMENTS:
1097  case ISD::CALL:
1098    // The only option for this is to custom lower it.
1099    Tmp3 = TLI.LowerOperation(Result.getValue(0), DAG);
1100    assert(Tmp3.Val && "Target didn't custom lower this node!");
1101    assert(Tmp3.Val->getNumValues() == Result.Val->getNumValues() &&
1102           "Lowering call/formal_arguments produced unexpected # results!");
1103
1104    // Since CALL/FORMAL_ARGUMENTS nodes produce multiple values, make sure to
1105    // remember that we legalized all of them, so it doesn't get relegalized.
1106    for (unsigned i = 0, e = Tmp3.Val->getNumValues(); i != e; ++i) {
1107      Tmp1 = LegalizeOp(Tmp3.getValue(i));
1108      if (Op.ResNo == i)
1109        Tmp2 = Tmp1;
1110      AddLegalizedOperand(SDOperand(Node, i), Tmp1);
1111    }
1112    return Tmp2;
1113   case ISD::EXTRACT_SUBREG: {
1114      Tmp1 = LegalizeOp(Node->getOperand(0));
1115      ConstantSDNode *idx = dyn_cast<ConstantSDNode>(Node->getOperand(1));
1116      assert(idx && "Operand must be a constant");
1117      Tmp2 = DAG.getTargetConstant(idx->getValue(), idx->getValueType(0));
1118      Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2);
1119    }
1120    break;
1121  case ISD::INSERT_SUBREG: {
1122      Tmp1 = LegalizeOp(Node->getOperand(0));
1123      Tmp2 = LegalizeOp(Node->getOperand(1));
1124      ConstantSDNode *idx = dyn_cast<ConstantSDNode>(Node->getOperand(2));
1125      assert(idx && "Operand must be a constant");
1126      Tmp3 = DAG.getTargetConstant(idx->getValue(), idx->getValueType(0));
1127      Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3);
1128    }
1129    break;
1130  case ISD::BUILD_VECTOR:
1131    switch (TLI.getOperationAction(ISD::BUILD_VECTOR, Node->getValueType(0))) {
1132    default: assert(0 && "This action is not supported yet!");
1133    case TargetLowering::Custom:
1134      Tmp3 = TLI.LowerOperation(Result, DAG);
1135      if (Tmp3.Val) {
1136        Result = Tmp3;
1137        break;
1138      }
1139      // FALLTHROUGH
1140    case TargetLowering::Expand:
1141      Result = ExpandBUILD_VECTOR(Result.Val);
1142      break;
1143    }
1144    break;
1145  case ISD::INSERT_VECTOR_ELT:
1146    Tmp1 = LegalizeOp(Node->getOperand(0));  // InVec
1147    Tmp2 = LegalizeOp(Node->getOperand(1));  // InVal
1148    Tmp3 = LegalizeOp(Node->getOperand(2));  // InEltNo
1149    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3);
1150
1151    switch (TLI.getOperationAction(ISD::INSERT_VECTOR_ELT,
1152                                   Node->getValueType(0))) {
1153    default: assert(0 && "This action is not supported yet!");
1154    case TargetLowering::Legal:
1155      break;
1156    case TargetLowering::Custom:
1157      Tmp3 = TLI.LowerOperation(Result, DAG);
1158      if (Tmp3.Val) {
1159        Result = Tmp3;
1160        break;
1161      }
1162      // FALLTHROUGH
1163    case TargetLowering::Expand: {
1164      // If the insert index is a constant, codegen this as a scalar_to_vector,
1165      // then a shuffle that inserts it into the right position in the vector.
1166      if (ConstantSDNode *InsertPos = dyn_cast<ConstantSDNode>(Tmp3)) {
1167        SDOperand ScVec = DAG.getNode(ISD::SCALAR_TO_VECTOR,
1168                                      Tmp1.getValueType(), Tmp2);
1169
1170        unsigned NumElts = MVT::getVectorNumElements(Tmp1.getValueType());
1171        MVT::ValueType ShufMaskVT = MVT::getIntVectorWithNumElements(NumElts);
1172        MVT::ValueType ShufMaskEltVT = MVT::getVectorElementType(ShufMaskVT);
1173
1174        // We generate a shuffle of InVec and ScVec, so the shuffle mask should
1175        // be 0,1,2,3,4,5... with the appropriate element replaced with elt 0 of
1176        // the RHS.
1177        SmallVector<SDOperand, 8> ShufOps;
1178        for (unsigned i = 0; i != NumElts; ++i) {
1179          if (i != InsertPos->getValue())
1180            ShufOps.push_back(DAG.getConstant(i, ShufMaskEltVT));
1181          else
1182            ShufOps.push_back(DAG.getConstant(NumElts, ShufMaskEltVT));
1183        }
1184        SDOperand ShufMask = DAG.getNode(ISD::BUILD_VECTOR, ShufMaskVT,
1185                                         &ShufOps[0], ShufOps.size());
1186
1187        Result = DAG.getNode(ISD::VECTOR_SHUFFLE, Tmp1.getValueType(),
1188                             Tmp1, ScVec, ShufMask);
1189        Result = LegalizeOp(Result);
1190        break;
1191      }
1192
1193      // If the target doesn't support this, we have to spill the input vector
1194      // to a temporary stack slot, update the element, then reload it.  This is
1195      // badness.  We could also load the value into a vector register (either
1196      // with a "move to register" or "extload into register" instruction, then
1197      // permute it into place, if the idx is a constant and if the idx is
1198      // supported by the target.
1199      MVT::ValueType VT    = Tmp1.getValueType();
1200      MVT::ValueType EltVT = Tmp2.getValueType();
1201      MVT::ValueType IdxVT = Tmp3.getValueType();
1202      MVT::ValueType PtrVT = TLI.getPointerTy();
1203      SDOperand StackPtr = CreateStackTemporary(VT);
1204      // Store the vector.
1205      SDOperand Ch = DAG.getStore(DAG.getEntryNode(), Tmp1, StackPtr, NULL, 0);
1206
1207      // Truncate or zero extend offset to target pointer type.
1208      unsigned CastOpc = (IdxVT > PtrVT) ? ISD::TRUNCATE : ISD::ZERO_EXTEND;
1209      Tmp3 = DAG.getNode(CastOpc, PtrVT, Tmp3);
1210      // Add the offset to the index.
1211      unsigned EltSize = MVT::getSizeInBits(EltVT)/8;
1212      Tmp3 = DAG.getNode(ISD::MUL, IdxVT, Tmp3,DAG.getConstant(EltSize, IdxVT));
1213      SDOperand StackPtr2 = DAG.getNode(ISD::ADD, IdxVT, Tmp3, StackPtr);
1214      // Store the scalar value.
1215      Ch = DAG.getStore(Ch, Tmp2, StackPtr2, NULL, 0);
1216      // Load the updated vector.
1217      Result = DAG.getLoad(VT, Ch, StackPtr, NULL, 0);
1218      break;
1219    }
1220    }
1221    break;
1222  case ISD::SCALAR_TO_VECTOR:
1223    if (!TLI.isTypeLegal(Node->getOperand(0).getValueType())) {
1224      Result = LegalizeOp(ExpandSCALAR_TO_VECTOR(Node));
1225      break;
1226    }
1227
1228    Tmp1 = LegalizeOp(Node->getOperand(0));  // InVal
1229    Result = DAG.UpdateNodeOperands(Result, Tmp1);
1230    switch (TLI.getOperationAction(ISD::SCALAR_TO_VECTOR,
1231                                   Node->getValueType(0))) {
1232    default: assert(0 && "This action is not supported yet!");
1233    case TargetLowering::Legal:
1234      break;
1235    case TargetLowering::Custom:
1236      Tmp3 = TLI.LowerOperation(Result, DAG);
1237      if (Tmp3.Val) {
1238        Result = Tmp3;
1239        break;
1240      }
1241      // FALLTHROUGH
1242    case TargetLowering::Expand:
1243      Result = LegalizeOp(ExpandSCALAR_TO_VECTOR(Node));
1244      break;
1245    }
1246    break;
1247  case ISD::VECTOR_SHUFFLE:
1248    Tmp1 = LegalizeOp(Node->getOperand(0));   // Legalize the input vectors,
1249    Tmp2 = LegalizeOp(Node->getOperand(1));   // but not the shuffle mask.
1250    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Node->getOperand(2));
1251
1252    // Allow targets to custom lower the SHUFFLEs they support.
1253    switch (TLI.getOperationAction(ISD::VECTOR_SHUFFLE,Result.getValueType())) {
1254    default: assert(0 && "Unknown operation action!");
1255    case TargetLowering::Legal:
1256      assert(isShuffleLegal(Result.getValueType(), Node->getOperand(2)) &&
1257             "vector shuffle should not be created if not legal!");
1258      break;
1259    case TargetLowering::Custom:
1260      Tmp3 = TLI.LowerOperation(Result, DAG);
1261      if (Tmp3.Val) {
1262        Result = Tmp3;
1263        break;
1264      }
1265      // FALLTHROUGH
1266    case TargetLowering::Expand: {
1267      MVT::ValueType VT = Node->getValueType(0);
1268      MVT::ValueType EltVT = MVT::getVectorElementType(VT);
1269      MVT::ValueType PtrVT = TLI.getPointerTy();
1270      SDOperand Mask = Node->getOperand(2);
1271      unsigned NumElems = Mask.getNumOperands();
1272      SmallVector<SDOperand,8> Ops;
1273      for (unsigned i = 0; i != NumElems; ++i) {
1274        SDOperand Arg = Mask.getOperand(i);
1275        if (Arg.getOpcode() == ISD::UNDEF) {
1276          Ops.push_back(DAG.getNode(ISD::UNDEF, EltVT));
1277        } else {
1278          assert(isa<ConstantSDNode>(Arg) && "Invalid VECTOR_SHUFFLE mask!");
1279          unsigned Idx = cast<ConstantSDNode>(Arg)->getValue();
1280          if (Idx < NumElems)
1281            Ops.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, EltVT, Tmp1,
1282                                      DAG.getConstant(Idx, PtrVT)));
1283          else
1284            Ops.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, EltVT, Tmp2,
1285                                      DAG.getConstant(Idx - NumElems, PtrVT)));
1286        }
1287      }
1288      Result = DAG.getNode(ISD::BUILD_VECTOR, VT, &Ops[0], Ops.size());
1289      break;
1290    }
1291    case TargetLowering::Promote: {
1292      // Change base type to a different vector type.
1293      MVT::ValueType OVT = Node->getValueType(0);
1294      MVT::ValueType NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), OVT);
1295
1296      // Cast the two input vectors.
1297      Tmp1 = DAG.getNode(ISD::BIT_CONVERT, NVT, Tmp1);
1298      Tmp2 = DAG.getNode(ISD::BIT_CONVERT, NVT, Tmp2);
1299
1300      // Convert the shuffle mask to the right # elements.
1301      Tmp3 = SDOperand(isShuffleLegal(OVT, Node->getOperand(2)), 0);
1302      assert(Tmp3.Val && "Shuffle not legal?");
1303      Result = DAG.getNode(ISD::VECTOR_SHUFFLE, NVT, Tmp1, Tmp2, Tmp3);
1304      Result = DAG.getNode(ISD::BIT_CONVERT, OVT, Result);
1305      break;
1306    }
1307    }
1308    break;
1309
1310  case ISD::EXTRACT_VECTOR_ELT:
1311    Tmp1 = Node->getOperand(0);
1312    Tmp2 = LegalizeOp(Node->getOperand(1));
1313    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2);
1314    Result = ExpandEXTRACT_VECTOR_ELT(Result);
1315    break;
1316
1317  case ISD::EXTRACT_SUBVECTOR:
1318    Tmp1 = Node->getOperand(0);
1319    Tmp2 = LegalizeOp(Node->getOperand(1));
1320    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2);
1321    Result = ExpandEXTRACT_SUBVECTOR(Result);
1322    break;
1323
1324  case ISD::CALLSEQ_START: {
1325    SDNode *CallEnd = FindCallEndFromCallStart(Node);
1326
1327    // Recursively Legalize all of the inputs of the call end that do not lead
1328    // to this call start.  This ensures that any libcalls that need be inserted
1329    // are inserted *before* the CALLSEQ_START.
1330    {SmallPtrSet<SDNode*, 32> NodesLeadingTo;
1331    for (unsigned i = 0, e = CallEnd->getNumOperands(); i != e; ++i)
1332      LegalizeAllNodesNotLeadingTo(CallEnd->getOperand(i).Val, Node,
1333                                   NodesLeadingTo);
1334    }
1335
1336    // Now that we legalized all of the inputs (which may have inserted
1337    // libcalls) create the new CALLSEQ_START node.
1338    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
1339
1340    // Merge in the last call, to ensure that this call start after the last
1341    // call ended.
1342    if (LastCALLSEQ_END.getOpcode() != ISD::EntryToken) {
1343      Tmp1 = DAG.getNode(ISD::TokenFactor, MVT::Other, Tmp1, LastCALLSEQ_END);
1344      Tmp1 = LegalizeOp(Tmp1);
1345    }
1346
1347    // Do not try to legalize the target-specific arguments (#1+).
1348    if (Tmp1 != Node->getOperand(0)) {
1349      SmallVector<SDOperand, 8> Ops(Node->op_begin(), Node->op_end());
1350      Ops[0] = Tmp1;
1351      Result = DAG.UpdateNodeOperands(Result, &Ops[0], Ops.size());
1352    }
1353
1354    // Remember that the CALLSEQ_START is legalized.
1355    AddLegalizedOperand(Op.getValue(0), Result);
1356    if (Node->getNumValues() == 2)    // If this has a flag result, remember it.
1357      AddLegalizedOperand(Op.getValue(1), Result.getValue(1));
1358
1359    // Now that the callseq_start and all of the non-call nodes above this call
1360    // sequence have been legalized, legalize the call itself.  During this
1361    // process, no libcalls can/will be inserted, guaranteeing that no calls
1362    // can overlap.
1363    assert(!IsLegalizingCall && "Inconsistent sequentialization of calls!");
1364    SDOperand InCallSEQ = LastCALLSEQ_END;
1365    // Note that we are selecting this call!
1366    LastCALLSEQ_END = SDOperand(CallEnd, 0);
1367    IsLegalizingCall = true;
1368
1369    // Legalize the call, starting from the CALLSEQ_END.
1370    LegalizeOp(LastCALLSEQ_END);
1371    assert(!IsLegalizingCall && "CALLSEQ_END should have cleared this!");
1372    return Result;
1373  }
1374  case ISD::CALLSEQ_END:
1375    // If the CALLSEQ_START node hasn't been legalized first, legalize it.  This
1376    // will cause this node to be legalized as well as handling libcalls right.
1377    if (LastCALLSEQ_END.Val != Node) {
1378      LegalizeOp(SDOperand(FindCallStartFromCallEnd(Node), 0));
1379      DenseMap<SDOperand, SDOperand>::iterator I = LegalizedNodes.find(Op);
1380      assert(I != LegalizedNodes.end() &&
1381             "Legalizing the call start should have legalized this node!");
1382      return I->second;
1383    }
1384
1385    // Otherwise, the call start has been legalized and everything is going
1386    // according to plan.  Just legalize ourselves normally here.
1387    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
1388    // Do not try to legalize the target-specific arguments (#1+), except for
1389    // an optional flag input.
1390    if (Node->getOperand(Node->getNumOperands()-1).getValueType() != MVT::Flag){
1391      if (Tmp1 != Node->getOperand(0)) {
1392        SmallVector<SDOperand, 8> Ops(Node->op_begin(), Node->op_end());
1393        Ops[0] = Tmp1;
1394        Result = DAG.UpdateNodeOperands(Result, &Ops[0], Ops.size());
1395      }
1396    } else {
1397      Tmp2 = LegalizeOp(Node->getOperand(Node->getNumOperands()-1));
1398      if (Tmp1 != Node->getOperand(0) ||
1399          Tmp2 != Node->getOperand(Node->getNumOperands()-1)) {
1400        SmallVector<SDOperand, 8> Ops(Node->op_begin(), Node->op_end());
1401        Ops[0] = Tmp1;
1402        Ops.back() = Tmp2;
1403        Result = DAG.UpdateNodeOperands(Result, &Ops[0], Ops.size());
1404      }
1405    }
1406    assert(IsLegalizingCall && "Call sequence imbalance between start/end?");
1407    // This finishes up call legalization.
1408    IsLegalizingCall = false;
1409
1410    // If the CALLSEQ_END node has a flag, remember that we legalized it.
1411    AddLegalizedOperand(SDOperand(Node, 0), Result.getValue(0));
1412    if (Node->getNumValues() == 2)
1413      AddLegalizedOperand(SDOperand(Node, 1), Result.getValue(1));
1414    return Result.getValue(Op.ResNo);
1415  case ISD::DYNAMIC_STACKALLOC: {
1416    MVT::ValueType VT = Node->getValueType(0);
1417    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
1418    Tmp2 = LegalizeOp(Node->getOperand(1));  // Legalize the size.
1419    Tmp3 = LegalizeOp(Node->getOperand(2));  // Legalize the alignment.
1420    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3);
1421
1422    Tmp1 = Result.getValue(0);
1423    Tmp2 = Result.getValue(1);
1424    switch (TLI.getOperationAction(Node->getOpcode(), VT)) {
1425    default: assert(0 && "This action is not supported yet!");
1426    case TargetLowering::Expand: {
1427      unsigned SPReg = TLI.getStackPointerRegisterToSaveRestore();
1428      assert(SPReg && "Target cannot require DYNAMIC_STACKALLOC expansion and"
1429             " not tell us which reg is the stack pointer!");
1430      SDOperand Chain = Tmp1.getOperand(0);
1431      SDOperand Size  = Tmp2.getOperand(1);
1432      SDOperand SP = DAG.getCopyFromReg(Chain, SPReg, VT);
1433      Chain = SP.getValue(1);
1434      unsigned Align = cast<ConstantSDNode>(Tmp3)->getValue();
1435      unsigned StackAlign =
1436        TLI.getTargetMachine().getFrameInfo()->getStackAlignment();
1437      if (Align > StackAlign)
1438        SP = DAG.getNode(ISD::AND, VT, SP,
1439                         DAG.getConstant(-(uint64_t)Align, VT));
1440      Tmp1 = DAG.getNode(ISD::SUB, VT, SP, Size);       // Value
1441      Tmp2 = DAG.getCopyToReg(Chain, SPReg, Tmp1);      // Output chain
1442      Tmp1 = LegalizeOp(Tmp1);
1443      Tmp2 = LegalizeOp(Tmp2);
1444      break;
1445    }
1446    case TargetLowering::Custom:
1447      Tmp3 = TLI.LowerOperation(Tmp1, DAG);
1448      if (Tmp3.Val) {
1449        Tmp1 = LegalizeOp(Tmp3);
1450        Tmp2 = LegalizeOp(Tmp3.getValue(1));
1451      }
1452      break;
1453    case TargetLowering::Legal:
1454      break;
1455    }
1456    // Since this op produce two values, make sure to remember that we
1457    // legalized both of them.
1458    AddLegalizedOperand(SDOperand(Node, 0), Tmp1);
1459    AddLegalizedOperand(SDOperand(Node, 1), Tmp2);
1460    return Op.ResNo ? Tmp2 : Tmp1;
1461  }
1462  case ISD::INLINEASM: {
1463    SmallVector<SDOperand, 8> Ops(Node->op_begin(), Node->op_end());
1464    bool Changed = false;
1465    // Legalize all of the operands of the inline asm, in case they are nodes
1466    // that need to be expanded or something.  Note we skip the asm string and
1467    // all of the TargetConstant flags.
1468    SDOperand Op = LegalizeOp(Ops[0]);
1469    Changed = Op != Ops[0];
1470    Ops[0] = Op;
1471
1472    bool HasInFlag = Ops.back().getValueType() == MVT::Flag;
1473    for (unsigned i = 2, e = Ops.size()-HasInFlag; i < e; ) {
1474      unsigned NumVals = cast<ConstantSDNode>(Ops[i])->getValue() >> 3;
1475      for (++i; NumVals; ++i, --NumVals) {
1476        SDOperand Op = LegalizeOp(Ops[i]);
1477        if (Op != Ops[i]) {
1478          Changed = true;
1479          Ops[i] = Op;
1480        }
1481      }
1482    }
1483
1484    if (HasInFlag) {
1485      Op = LegalizeOp(Ops.back());
1486      Changed |= Op != Ops.back();
1487      Ops.back() = Op;
1488    }
1489
1490    if (Changed)
1491      Result = DAG.UpdateNodeOperands(Result, &Ops[0], Ops.size());
1492
1493    // INLINE asm returns a chain and flag, make sure to add both to the map.
1494    AddLegalizedOperand(SDOperand(Node, 0), Result.getValue(0));
1495    AddLegalizedOperand(SDOperand(Node, 1), Result.getValue(1));
1496    return Result.getValue(Op.ResNo);
1497  }
1498  case ISD::BR:
1499    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
1500    // Ensure that libcalls are emitted before a branch.
1501    Tmp1 = DAG.getNode(ISD::TokenFactor, MVT::Other, Tmp1, LastCALLSEQ_END);
1502    Tmp1 = LegalizeOp(Tmp1);
1503    LastCALLSEQ_END = DAG.getEntryNode();
1504
1505    Result = DAG.UpdateNodeOperands(Result, Tmp1, Node->getOperand(1));
1506    break;
1507  case ISD::BRIND:
1508    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
1509    // Ensure that libcalls are emitted before a branch.
1510    Tmp1 = DAG.getNode(ISD::TokenFactor, MVT::Other, Tmp1, LastCALLSEQ_END);
1511    Tmp1 = LegalizeOp(Tmp1);
1512    LastCALLSEQ_END = DAG.getEntryNode();
1513
1514    switch (getTypeAction(Node->getOperand(1).getValueType())) {
1515    default: assert(0 && "Indirect target must be legal type (pointer)!");
1516    case Legal:
1517      Tmp2 = LegalizeOp(Node->getOperand(1)); // Legalize the condition.
1518      break;
1519    }
1520    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2);
1521    break;
1522  case ISD::BR_JT:
1523    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
1524    // Ensure that libcalls are emitted before a branch.
1525    Tmp1 = DAG.getNode(ISD::TokenFactor, MVT::Other, Tmp1, LastCALLSEQ_END);
1526    Tmp1 = LegalizeOp(Tmp1);
1527    LastCALLSEQ_END = DAG.getEntryNode();
1528
1529    Tmp2 = LegalizeOp(Node->getOperand(1));  // Legalize the jumptable node.
1530    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Node->getOperand(2));
1531
1532    switch (TLI.getOperationAction(ISD::BR_JT, MVT::Other)) {
1533    default: assert(0 && "This action is not supported yet!");
1534    case TargetLowering::Legal: break;
1535    case TargetLowering::Custom:
1536      Tmp1 = TLI.LowerOperation(Result, DAG);
1537      if (Tmp1.Val) Result = Tmp1;
1538      break;
1539    case TargetLowering::Expand: {
1540      SDOperand Chain = Result.getOperand(0);
1541      SDOperand Table = Result.getOperand(1);
1542      SDOperand Index = Result.getOperand(2);
1543
1544      MVT::ValueType PTy = TLI.getPointerTy();
1545      MachineFunction &MF = DAG.getMachineFunction();
1546      unsigned EntrySize = MF.getJumpTableInfo()->getEntrySize();
1547      Index= DAG.getNode(ISD::MUL, PTy, Index, DAG.getConstant(EntrySize, PTy));
1548      SDOperand Addr = DAG.getNode(ISD::ADD, PTy, Index, Table);
1549
1550      SDOperand LD;
1551      switch (EntrySize) {
1552      default: assert(0 && "Size of jump table not supported yet."); break;
1553      case 4: LD = DAG.getLoad(MVT::i32, Chain, Addr, NULL, 0); break;
1554      case 8: LD = DAG.getLoad(MVT::i64, Chain, Addr, NULL, 0); break;
1555      }
1556
1557      if (TLI.getTargetMachine().getRelocationModel() == Reloc::PIC_) {
1558        // For PIC, the sequence is:
1559        // BRIND(load(Jumptable + index) + RelocBase)
1560        // RelocBase is the JumpTable on PPC and X86, GOT on Alpha
1561        SDOperand Reloc;
1562        if (TLI.usesGlobalOffsetTable())
1563          Reloc = DAG.getNode(ISD::GLOBAL_OFFSET_TABLE, PTy);
1564        else
1565          Reloc = Table;
1566        Addr = (PTy != MVT::i32) ? DAG.getNode(ISD::SIGN_EXTEND, PTy, LD) : LD;
1567        Addr = DAG.getNode(ISD::ADD, PTy, Addr, Reloc);
1568        Result = DAG.getNode(ISD::BRIND, MVT::Other, LD.getValue(1), Addr);
1569      } else {
1570        Result = DAG.getNode(ISD::BRIND, MVT::Other, LD.getValue(1), LD);
1571      }
1572    }
1573    }
1574    break;
1575  case ISD::BRCOND:
1576    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
1577    // Ensure that libcalls are emitted before a return.
1578    Tmp1 = DAG.getNode(ISD::TokenFactor, MVT::Other, Tmp1, LastCALLSEQ_END);
1579    Tmp1 = LegalizeOp(Tmp1);
1580    LastCALLSEQ_END = DAG.getEntryNode();
1581
1582    switch (getTypeAction(Node->getOperand(1).getValueType())) {
1583    case Expand: assert(0 && "It's impossible to expand bools");
1584    case Legal:
1585      Tmp2 = LegalizeOp(Node->getOperand(1)); // Legalize the condition.
1586      break;
1587    case Promote:
1588      Tmp2 = PromoteOp(Node->getOperand(1));  // Promote the condition.
1589
1590      // The top bits of the promoted condition are not necessarily zero, ensure
1591      // that the value is properly zero extended.
1592      if (!DAG.MaskedValueIsZero(Tmp2,
1593                                 MVT::getIntVTBitMask(Tmp2.getValueType())^1))
1594        Tmp2 = DAG.getZeroExtendInReg(Tmp2, MVT::i1);
1595      break;
1596    }
1597
1598    // Basic block destination (Op#2) is always legal.
1599    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Node->getOperand(2));
1600
1601    switch (TLI.getOperationAction(ISD::BRCOND, MVT::Other)) {
1602    default: assert(0 && "This action is not supported yet!");
1603    case TargetLowering::Legal: break;
1604    case TargetLowering::Custom:
1605      Tmp1 = TLI.LowerOperation(Result, DAG);
1606      if (Tmp1.Val) Result = Tmp1;
1607      break;
1608    case TargetLowering::Expand:
1609      // Expand brcond's setcc into its constituent parts and create a BR_CC
1610      // Node.
1611      if (Tmp2.getOpcode() == ISD::SETCC) {
1612        Result = DAG.getNode(ISD::BR_CC, MVT::Other, Tmp1, Tmp2.getOperand(2),
1613                             Tmp2.getOperand(0), Tmp2.getOperand(1),
1614                             Node->getOperand(2));
1615      } else {
1616        Result = DAG.getNode(ISD::BR_CC, MVT::Other, Tmp1,
1617                             DAG.getCondCode(ISD::SETNE), Tmp2,
1618                             DAG.getConstant(0, Tmp2.getValueType()),
1619                             Node->getOperand(2));
1620      }
1621      break;
1622    }
1623    break;
1624  case ISD::BR_CC:
1625    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
1626    // Ensure that libcalls are emitted before a branch.
1627    Tmp1 = DAG.getNode(ISD::TokenFactor, MVT::Other, Tmp1, LastCALLSEQ_END);
1628    Tmp1 = LegalizeOp(Tmp1);
1629    Tmp2 = Node->getOperand(2);              // LHS
1630    Tmp3 = Node->getOperand(3);              // RHS
1631    Tmp4 = Node->getOperand(1);              // CC
1632
1633    LegalizeSetCCOperands(Tmp2, Tmp3, Tmp4);
1634    LastCALLSEQ_END = DAG.getEntryNode();
1635
1636    // If we didn't get both a LHS and RHS back from LegalizeSetCCOperands,
1637    // the LHS is a legal SETCC itself.  In this case, we need to compare
1638    // the result against zero to select between true and false values.
1639    if (Tmp3.Val == 0) {
1640      Tmp3 = DAG.getConstant(0, Tmp2.getValueType());
1641      Tmp4 = DAG.getCondCode(ISD::SETNE);
1642    }
1643
1644    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp4, Tmp2, Tmp3,
1645                                    Node->getOperand(4));
1646
1647    switch (TLI.getOperationAction(ISD::BR_CC, Tmp3.getValueType())) {
1648    default: assert(0 && "Unexpected action for BR_CC!");
1649    case TargetLowering::Legal: break;
1650    case TargetLowering::Custom:
1651      Tmp4 = TLI.LowerOperation(Result, DAG);
1652      if (Tmp4.Val) Result = Tmp4;
1653      break;
1654    }
1655    break;
1656  case ISD::LOAD: {
1657    LoadSDNode *LD = cast<LoadSDNode>(Node);
1658    Tmp1 = LegalizeOp(LD->getChain());   // Legalize the chain.
1659    Tmp2 = LegalizeOp(LD->getBasePtr()); // Legalize the base pointer.
1660
1661    ISD::LoadExtType ExtType = LD->getExtensionType();
1662    if (ExtType == ISD::NON_EXTLOAD) {
1663      MVT::ValueType VT = Node->getValueType(0);
1664      Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, LD->getOffset());
1665      Tmp3 = Result.getValue(0);
1666      Tmp4 = Result.getValue(1);
1667
1668      switch (TLI.getOperationAction(Node->getOpcode(), VT)) {
1669      default: assert(0 && "This action is not supported yet!");
1670      case TargetLowering::Legal:
1671        // If this is an unaligned load and the target doesn't support it,
1672        // expand it.
1673        if (!TLI.allowsUnalignedMemoryAccesses()) {
1674          unsigned ABIAlignment = TLI.getTargetData()->
1675            getABITypeAlignment(MVT::getTypeForValueType(LD->getLoadedVT()));
1676          if (LD->getAlignment() < ABIAlignment){
1677            Result = ExpandUnalignedLoad(cast<LoadSDNode>(Result.Val), DAG,
1678                                         TLI);
1679            Tmp3 = Result.getOperand(0);
1680            Tmp4 = Result.getOperand(1);
1681            Tmp3 = LegalizeOp(Tmp3);
1682            Tmp4 = LegalizeOp(Tmp4);
1683          }
1684        }
1685        break;
1686      case TargetLowering::Custom:
1687        Tmp1 = TLI.LowerOperation(Tmp3, DAG);
1688        if (Tmp1.Val) {
1689          Tmp3 = LegalizeOp(Tmp1);
1690          Tmp4 = LegalizeOp(Tmp1.getValue(1));
1691        }
1692        break;
1693      case TargetLowering::Promote: {
1694        // Only promote a load of vector type to another.
1695        assert(MVT::isVector(VT) && "Cannot promote this load!");
1696        // Change base type to a different vector type.
1697        MVT::ValueType NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), VT);
1698
1699        Tmp1 = DAG.getLoad(NVT, Tmp1, Tmp2, LD->getSrcValue(),
1700                           LD->getSrcValueOffset(),
1701                           LD->isVolatile(), LD->getAlignment());
1702        Tmp3 = LegalizeOp(DAG.getNode(ISD::BIT_CONVERT, VT, Tmp1));
1703        Tmp4 = LegalizeOp(Tmp1.getValue(1));
1704        break;
1705      }
1706      }
1707      // Since loads produce two values, make sure to remember that we
1708      // legalized both of them.
1709      AddLegalizedOperand(SDOperand(Node, 0), Tmp3);
1710      AddLegalizedOperand(SDOperand(Node, 1), Tmp4);
1711      return Op.ResNo ? Tmp4 : Tmp3;
1712    } else {
1713      MVT::ValueType SrcVT = LD->getLoadedVT();
1714      switch (TLI.getLoadXAction(ExtType, SrcVT)) {
1715      default: assert(0 && "This action is not supported yet!");
1716      case TargetLowering::Promote:
1717        assert(SrcVT == MVT::i1 &&
1718               "Can only promote extending LOAD from i1 -> i8!");
1719        Result = DAG.getExtLoad(ExtType, Node->getValueType(0), Tmp1, Tmp2,
1720                                LD->getSrcValue(), LD->getSrcValueOffset(),
1721                                MVT::i8, LD->isVolatile(), LD->getAlignment());
1722      Tmp1 = Result.getValue(0);
1723      Tmp2 = Result.getValue(1);
1724      break;
1725      case TargetLowering::Custom:
1726        isCustom = true;
1727        // FALLTHROUGH
1728      case TargetLowering::Legal:
1729        Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, LD->getOffset());
1730        Tmp1 = Result.getValue(0);
1731        Tmp2 = Result.getValue(1);
1732
1733        if (isCustom) {
1734          Tmp3 = TLI.LowerOperation(Result, DAG);
1735          if (Tmp3.Val) {
1736            Tmp1 = LegalizeOp(Tmp3);
1737            Tmp2 = LegalizeOp(Tmp3.getValue(1));
1738          }
1739        } else {
1740          // If this is an unaligned load and the target doesn't support it,
1741          // expand it.
1742          if (!TLI.allowsUnalignedMemoryAccesses()) {
1743            unsigned ABIAlignment = TLI.getTargetData()->
1744              getABITypeAlignment(MVT::getTypeForValueType(LD->getLoadedVT()));
1745            if (LD->getAlignment() < ABIAlignment){
1746              Result = ExpandUnalignedLoad(cast<LoadSDNode>(Result.Val), DAG,
1747                                           TLI);
1748              Tmp1 = Result.getOperand(0);
1749              Tmp2 = Result.getOperand(1);
1750              Tmp1 = LegalizeOp(Tmp1);
1751              Tmp2 = LegalizeOp(Tmp2);
1752            }
1753          }
1754        }
1755        break;
1756      case TargetLowering::Expand:
1757        // f64 = EXTLOAD f32 should expand to LOAD, FP_EXTEND
1758        if (SrcVT == MVT::f32 && Node->getValueType(0) == MVT::f64) {
1759          SDOperand Load = DAG.getLoad(SrcVT, Tmp1, Tmp2, LD->getSrcValue(),
1760                                       LD->getSrcValueOffset(),
1761                                       LD->isVolatile(), LD->getAlignment());
1762          Result = DAG.getNode(ISD::FP_EXTEND, Node->getValueType(0), Load);
1763          Tmp1 = LegalizeOp(Result);  // Relegalize new nodes.
1764          Tmp2 = LegalizeOp(Load.getValue(1));
1765          break;
1766        }
1767        assert(ExtType != ISD::EXTLOAD &&"EXTLOAD should always be supported!");
1768        // Turn the unsupported load into an EXTLOAD followed by an explicit
1769        // zero/sign extend inreg.
1770        Result = DAG.getExtLoad(ISD::EXTLOAD, Node->getValueType(0),
1771                                Tmp1, Tmp2, LD->getSrcValue(),
1772                                LD->getSrcValueOffset(), SrcVT,
1773                                LD->isVolatile(), LD->getAlignment());
1774        SDOperand ValRes;
1775        if (ExtType == ISD::SEXTLOAD)
1776          ValRes = DAG.getNode(ISD::SIGN_EXTEND_INREG, Result.getValueType(),
1777                               Result, DAG.getValueType(SrcVT));
1778        else
1779          ValRes = DAG.getZeroExtendInReg(Result, SrcVT);
1780        Tmp1 = LegalizeOp(ValRes);  // Relegalize new nodes.
1781        Tmp2 = LegalizeOp(Result.getValue(1));  // Relegalize new nodes.
1782        break;
1783      }
1784      // Since loads produce two values, make sure to remember that we legalized
1785      // both of them.
1786      AddLegalizedOperand(SDOperand(Node, 0), Tmp1);
1787      AddLegalizedOperand(SDOperand(Node, 1), Tmp2);
1788      return Op.ResNo ? Tmp2 : Tmp1;
1789    }
1790  }
1791  case ISD::EXTRACT_ELEMENT: {
1792    MVT::ValueType OpTy = Node->getOperand(0).getValueType();
1793    switch (getTypeAction(OpTy)) {
1794    default: assert(0 && "EXTRACT_ELEMENT action for type unimplemented!");
1795    case Legal:
1796      if (cast<ConstantSDNode>(Node->getOperand(1))->getValue()) {
1797        // 1 -> Hi
1798        Result = DAG.getNode(ISD::SRL, OpTy, Node->getOperand(0),
1799                             DAG.getConstant(MVT::getSizeInBits(OpTy)/2,
1800                                             TLI.getShiftAmountTy()));
1801        Result = DAG.getNode(ISD::TRUNCATE, Node->getValueType(0), Result);
1802      } else {
1803        // 0 -> Lo
1804        Result = DAG.getNode(ISD::TRUNCATE, Node->getValueType(0),
1805                             Node->getOperand(0));
1806      }
1807      break;
1808    case Expand:
1809      // Get both the low and high parts.
1810      ExpandOp(Node->getOperand(0), Tmp1, Tmp2);
1811      if (cast<ConstantSDNode>(Node->getOperand(1))->getValue())
1812        Result = Tmp2;  // 1 -> Hi
1813      else
1814        Result = Tmp1;  // 0 -> Lo
1815      break;
1816    }
1817    break;
1818  }
1819
1820  case ISD::CopyToReg:
1821    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
1822
1823    assert(isTypeLegal(Node->getOperand(2).getValueType()) &&
1824           "Register type must be legal!");
1825    // Legalize the incoming value (must be a legal type).
1826    Tmp2 = LegalizeOp(Node->getOperand(2));
1827    if (Node->getNumValues() == 1) {
1828      Result = DAG.UpdateNodeOperands(Result, Tmp1, Node->getOperand(1), Tmp2);
1829    } else {
1830      assert(Node->getNumValues() == 2 && "Unknown CopyToReg");
1831      if (Node->getNumOperands() == 4) {
1832        Tmp3 = LegalizeOp(Node->getOperand(3));
1833        Result = DAG.UpdateNodeOperands(Result, Tmp1, Node->getOperand(1), Tmp2,
1834                                        Tmp3);
1835      } else {
1836        Result = DAG.UpdateNodeOperands(Result, Tmp1, Node->getOperand(1),Tmp2);
1837      }
1838
1839      // Since this produces two values, make sure to remember that we legalized
1840      // both of them.
1841      AddLegalizedOperand(SDOperand(Node, 0), Result.getValue(0));
1842      AddLegalizedOperand(SDOperand(Node, 1), Result.getValue(1));
1843      return Result;
1844    }
1845    break;
1846
1847  case ISD::RET:
1848    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
1849
1850    // Ensure that libcalls are emitted before a return.
1851    Tmp1 = DAG.getNode(ISD::TokenFactor, MVT::Other, Tmp1, LastCALLSEQ_END);
1852    Tmp1 = LegalizeOp(Tmp1);
1853    LastCALLSEQ_END = DAG.getEntryNode();
1854
1855    switch (Node->getNumOperands()) {
1856    case 3:  // ret val
1857      Tmp2 = Node->getOperand(1);
1858      Tmp3 = Node->getOperand(2);  // Signness
1859      switch (getTypeAction(Tmp2.getValueType())) {
1860      case Legal:
1861        Result = DAG.UpdateNodeOperands(Result, Tmp1, LegalizeOp(Tmp2), Tmp3);
1862        break;
1863      case Expand:
1864        if (!MVT::isVector(Tmp2.getValueType())) {
1865          SDOperand Lo, Hi;
1866          ExpandOp(Tmp2, Lo, Hi);
1867
1868          // Big endian systems want the hi reg first.
1869          if (!TLI.isLittleEndian())
1870            std::swap(Lo, Hi);
1871
1872          if (Hi.Val)
1873            Result = DAG.getNode(ISD::RET, MVT::Other, Tmp1, Lo, Tmp3, Hi,Tmp3);
1874          else
1875            Result = DAG.getNode(ISD::RET, MVT::Other, Tmp1, Lo, Tmp3);
1876          Result = LegalizeOp(Result);
1877        } else {
1878          SDNode *InVal = Tmp2.Val;
1879          unsigned NumElems = MVT::getVectorNumElements(InVal->getValueType(0));
1880          MVT::ValueType EVT = MVT::getVectorElementType(InVal->getValueType(0));
1881
1882          // Figure out if there is a simple type corresponding to this Vector
1883          // type.  If so, convert to the vector type.
1884          MVT::ValueType TVT = MVT::getVectorType(EVT, NumElems);
1885          if (TLI.isTypeLegal(TVT)) {
1886            // Turn this into a return of the vector type.
1887            Tmp2 = LegalizeOp(Tmp2);
1888            Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3);
1889          } else if (NumElems == 1) {
1890            // Turn this into a return of the scalar type.
1891            Tmp2 = ScalarizeVectorOp(Tmp2);
1892            Tmp2 = LegalizeOp(Tmp2);
1893            Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3);
1894
1895            // FIXME: Returns of gcc generic vectors smaller than a legal type
1896            // should be returned in integer registers!
1897
1898            // The scalarized value type may not be legal, e.g. it might require
1899            // promotion or expansion.  Relegalize the return.
1900            Result = LegalizeOp(Result);
1901          } else {
1902            // FIXME: Returns of gcc generic vectors larger than a legal vector
1903            // type should be returned by reference!
1904            SDOperand Lo, Hi;
1905            SplitVectorOp(Tmp2, Lo, Hi);
1906            Result = DAG.getNode(ISD::RET, MVT::Other, Tmp1, Lo, Tmp3, Hi,Tmp3);
1907            Result = LegalizeOp(Result);
1908          }
1909        }
1910        break;
1911      case Promote:
1912        Tmp2 = PromoteOp(Node->getOperand(1));
1913        Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3);
1914        Result = LegalizeOp(Result);
1915        break;
1916      }
1917      break;
1918    case 1:  // ret void
1919      Result = DAG.UpdateNodeOperands(Result, Tmp1);
1920      break;
1921    default: { // ret <values>
1922      SmallVector<SDOperand, 8> NewValues;
1923      NewValues.push_back(Tmp1);
1924      for (unsigned i = 1, e = Node->getNumOperands(); i < e; i += 2)
1925        switch (getTypeAction(Node->getOperand(i).getValueType())) {
1926        case Legal:
1927          NewValues.push_back(LegalizeOp(Node->getOperand(i)));
1928          NewValues.push_back(Node->getOperand(i+1));
1929          break;
1930        case Expand: {
1931          SDOperand Lo, Hi;
1932          assert(!MVT::isExtendedVT(Node->getOperand(i).getValueType()) &&
1933                 "FIXME: TODO: implement returning non-legal vector types!");
1934          ExpandOp(Node->getOperand(i), Lo, Hi);
1935          NewValues.push_back(Lo);
1936          NewValues.push_back(Node->getOperand(i+1));
1937          if (Hi.Val) {
1938            NewValues.push_back(Hi);
1939            NewValues.push_back(Node->getOperand(i+1));
1940          }
1941          break;
1942        }
1943        case Promote:
1944          assert(0 && "Can't promote multiple return value yet!");
1945        }
1946
1947      if (NewValues.size() == Node->getNumOperands())
1948        Result = DAG.UpdateNodeOperands(Result, &NewValues[0],NewValues.size());
1949      else
1950        Result = DAG.getNode(ISD::RET, MVT::Other,
1951                             &NewValues[0], NewValues.size());
1952      break;
1953    }
1954    }
1955
1956    if (Result.getOpcode() == ISD::RET) {
1957      switch (TLI.getOperationAction(Result.getOpcode(), MVT::Other)) {
1958      default: assert(0 && "This action is not supported yet!");
1959      case TargetLowering::Legal: break;
1960      case TargetLowering::Custom:
1961        Tmp1 = TLI.LowerOperation(Result, DAG);
1962        if (Tmp1.Val) Result = Tmp1;
1963        break;
1964      }
1965    }
1966    break;
1967  case ISD::STORE: {
1968    StoreSDNode *ST = cast<StoreSDNode>(Node);
1969    Tmp1 = LegalizeOp(ST->getChain());    // Legalize the chain.
1970    Tmp2 = LegalizeOp(ST->getBasePtr());  // Legalize the pointer.
1971    int SVOffset = ST->getSrcValueOffset();
1972    unsigned Alignment = ST->getAlignment();
1973    bool isVolatile = ST->isVolatile();
1974
1975    if (!ST->isTruncatingStore()) {
1976      // Turn 'store float 1.0, Ptr' -> 'store int 0x12345678, Ptr'
1977      // FIXME: We shouldn't do this for TargetConstantFP's.
1978      // FIXME: move this to the DAG Combiner!  Note that we can't regress due
1979      // to phase ordering between legalized code and the dag combiner.  This
1980      // probably means that we need to integrate dag combiner and legalizer
1981      // together.
1982      // We generally can't do this one for long doubles.
1983      if (ConstantFPSDNode *CFP =dyn_cast<ConstantFPSDNode>(ST->getValue())) {
1984        if (CFP->getValueType(0) == MVT::f32) {
1985          Tmp3 = DAG.getConstant((uint32_t)CFP->getValueAPF().
1986                                          convertToAPInt().getZExtValue(),
1987                                  MVT::i32);
1988          Result = DAG.getStore(Tmp1, Tmp3, Tmp2, ST->getSrcValue(),
1989                                SVOffset, isVolatile, Alignment);
1990          break;
1991        } else if (CFP->getValueType(0) == MVT::f64) {
1992          Tmp3 = DAG.getConstant(CFP->getValueAPF().convertToAPInt().
1993                                   getZExtValue(), MVT::i64);
1994          Result = DAG.getStore(Tmp1, Tmp3, Tmp2, ST->getSrcValue(),
1995                                SVOffset, isVolatile, Alignment);
1996          break;
1997        }
1998      }
1999
2000      switch (getTypeAction(ST->getStoredVT())) {
2001      case Legal: {
2002        Tmp3 = LegalizeOp(ST->getValue());
2003        Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp3, Tmp2,
2004                                        ST->getOffset());
2005
2006        MVT::ValueType VT = Tmp3.getValueType();
2007        switch (TLI.getOperationAction(ISD::STORE, VT)) {
2008        default: assert(0 && "This action is not supported yet!");
2009        case TargetLowering::Legal:
2010          // If this is an unaligned store and the target doesn't support it,
2011          // expand it.
2012          if (!TLI.allowsUnalignedMemoryAccesses()) {
2013            unsigned ABIAlignment = TLI.getTargetData()->
2014              getABITypeAlignment(MVT::getTypeForValueType(ST->getStoredVT()));
2015            if (ST->getAlignment() < ABIAlignment)
2016              Result = ExpandUnalignedStore(cast<StoreSDNode>(Result.Val), DAG,
2017                                            TLI);
2018          }
2019          break;
2020        case TargetLowering::Custom:
2021          Tmp1 = TLI.LowerOperation(Result, DAG);
2022          if (Tmp1.Val) Result = Tmp1;
2023          break;
2024        case TargetLowering::Promote:
2025          assert(MVT::isVector(VT) && "Unknown legal promote case!");
2026          Tmp3 = DAG.getNode(ISD::BIT_CONVERT,
2027                             TLI.getTypeToPromoteTo(ISD::STORE, VT), Tmp3);
2028          Result = DAG.getStore(Tmp1, Tmp3, Tmp2,
2029                                ST->getSrcValue(), SVOffset, isVolatile,
2030                                Alignment);
2031          break;
2032        }
2033        break;
2034      }
2035      case Promote:
2036        // Truncate the value and store the result.
2037        Tmp3 = PromoteOp(ST->getValue());
2038        Result = DAG.getTruncStore(Tmp1, Tmp3, Tmp2, ST->getSrcValue(),
2039                                   SVOffset, ST->getStoredVT(),
2040                                   isVolatile, Alignment);
2041        break;
2042
2043      case Expand:
2044        unsigned IncrementSize = 0;
2045        SDOperand Lo, Hi;
2046
2047        // If this is a vector type, then we have to calculate the increment as
2048        // the product of the element size in bytes, and the number of elements
2049        // in the high half of the vector.
2050        if (MVT::isVector(ST->getValue().getValueType())) {
2051          SDNode *InVal = ST->getValue().Val;
2052          unsigned NumElems = MVT::getVectorNumElements(InVal->getValueType(0));
2053          MVT::ValueType EVT = MVT::getVectorElementType(InVal->getValueType(0));
2054
2055          // Figure out if there is a simple type corresponding to this Vector
2056          // type.  If so, convert to the vector type.
2057          MVT::ValueType TVT = MVT::getVectorType(EVT, NumElems);
2058          if (TLI.isTypeLegal(TVT)) {
2059            // Turn this into a normal store of the vector type.
2060            Tmp3 = LegalizeOp(Node->getOperand(1));
2061            Result = DAG.getStore(Tmp1, Tmp3, Tmp2, ST->getSrcValue(),
2062                                  SVOffset, isVolatile, Alignment);
2063            Result = LegalizeOp(Result);
2064            break;
2065          } else if (NumElems == 1) {
2066            // Turn this into a normal store of the scalar type.
2067            Tmp3 = ScalarizeVectorOp(Node->getOperand(1));
2068            Result = DAG.getStore(Tmp1, Tmp3, Tmp2, ST->getSrcValue(),
2069                                  SVOffset, isVolatile, Alignment);
2070            // The scalarized value type may not be legal, e.g. it might require
2071            // promotion or expansion.  Relegalize the scalar store.
2072            Result = LegalizeOp(Result);
2073            break;
2074          } else {
2075            SplitVectorOp(Node->getOperand(1), Lo, Hi);
2076            IncrementSize = NumElems/2 * MVT::getSizeInBits(EVT)/8;
2077          }
2078        } else {
2079          ExpandOp(Node->getOperand(1), Lo, Hi);
2080          IncrementSize = Hi.Val ? MVT::getSizeInBits(Hi.getValueType())/8 : 0;
2081
2082          if (!TLI.isLittleEndian())
2083            std::swap(Lo, Hi);
2084        }
2085
2086        Lo = DAG.getStore(Tmp1, Lo, Tmp2, ST->getSrcValue(),
2087                          SVOffset, isVolatile, Alignment);
2088
2089        if (Hi.Val == NULL) {
2090          // Must be int <-> float one-to-one expansion.
2091          Result = Lo;
2092          break;
2093        }
2094
2095        Tmp2 = DAG.getNode(ISD::ADD, Tmp2.getValueType(), Tmp2,
2096                           getIntPtrConstant(IncrementSize));
2097        assert(isTypeLegal(Tmp2.getValueType()) &&
2098               "Pointers must be legal!");
2099        SVOffset += IncrementSize;
2100        if (Alignment > IncrementSize)
2101          Alignment = IncrementSize;
2102        Hi = DAG.getStore(Tmp1, Hi, Tmp2, ST->getSrcValue(),
2103                          SVOffset, isVolatile, Alignment);
2104        Result = DAG.getNode(ISD::TokenFactor, MVT::Other, Lo, Hi);
2105        break;
2106      }
2107    } else {
2108      // Truncating store
2109      assert(isTypeLegal(ST->getValue().getValueType()) &&
2110             "Cannot handle illegal TRUNCSTORE yet!");
2111      Tmp3 = LegalizeOp(ST->getValue());
2112
2113      // The only promote case we handle is TRUNCSTORE:i1 X into
2114      //   -> TRUNCSTORE:i8 (and X, 1)
2115      if (ST->getStoredVT() == MVT::i1 &&
2116          TLI.getStoreXAction(MVT::i1) == TargetLowering::Promote) {
2117        // Promote the bool to a mask then store.
2118        Tmp3 = DAG.getNode(ISD::AND, Tmp3.getValueType(), Tmp3,
2119                           DAG.getConstant(1, Tmp3.getValueType()));
2120        Result = DAG.getTruncStore(Tmp1, Tmp3, Tmp2, ST->getSrcValue(),
2121                                   SVOffset, MVT::i8,
2122                                   isVolatile, Alignment);
2123      } else if (Tmp1 != ST->getChain() || Tmp3 != ST->getValue() ||
2124                 Tmp2 != ST->getBasePtr()) {
2125        Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp3, Tmp2,
2126                                        ST->getOffset());
2127      }
2128
2129      MVT::ValueType StVT = cast<StoreSDNode>(Result.Val)->getStoredVT();
2130      switch (TLI.getStoreXAction(StVT)) {
2131      default: assert(0 && "This action is not supported yet!");
2132      case TargetLowering::Legal:
2133        // If this is an unaligned store and the target doesn't support it,
2134        // expand it.
2135        if (!TLI.allowsUnalignedMemoryAccesses()) {
2136          unsigned ABIAlignment = TLI.getTargetData()->
2137            getABITypeAlignment(MVT::getTypeForValueType(ST->getStoredVT()));
2138          if (ST->getAlignment() < ABIAlignment)
2139            Result = ExpandUnalignedStore(cast<StoreSDNode>(Result.Val), DAG,
2140                                          TLI);
2141        }
2142        break;
2143      case TargetLowering::Custom:
2144        Tmp1 = TLI.LowerOperation(Result, DAG);
2145        if (Tmp1.Val) Result = Tmp1;
2146        break;
2147      }
2148    }
2149    break;
2150  }
2151  case ISD::PCMARKER:
2152    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
2153    Result = DAG.UpdateNodeOperands(Result, Tmp1, Node->getOperand(1));
2154    break;
2155  case ISD::STACKSAVE:
2156    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
2157    Result = DAG.UpdateNodeOperands(Result, Tmp1);
2158    Tmp1 = Result.getValue(0);
2159    Tmp2 = Result.getValue(1);
2160
2161    switch (TLI.getOperationAction(ISD::STACKSAVE, MVT::Other)) {
2162    default: assert(0 && "This action is not supported yet!");
2163    case TargetLowering::Legal: break;
2164    case TargetLowering::Custom:
2165      Tmp3 = TLI.LowerOperation(Result, DAG);
2166      if (Tmp3.Val) {
2167        Tmp1 = LegalizeOp(Tmp3);
2168        Tmp2 = LegalizeOp(Tmp3.getValue(1));
2169      }
2170      break;
2171    case TargetLowering::Expand:
2172      // Expand to CopyFromReg if the target set
2173      // StackPointerRegisterToSaveRestore.
2174      if (unsigned SP = TLI.getStackPointerRegisterToSaveRestore()) {
2175        Tmp1 = DAG.getCopyFromReg(Result.getOperand(0), SP,
2176                                  Node->getValueType(0));
2177        Tmp2 = Tmp1.getValue(1);
2178      } else {
2179        Tmp1 = DAG.getNode(ISD::UNDEF, Node->getValueType(0));
2180        Tmp2 = Node->getOperand(0);
2181      }
2182      break;
2183    }
2184
2185    // Since stacksave produce two values, make sure to remember that we
2186    // legalized both of them.
2187    AddLegalizedOperand(SDOperand(Node, 0), Tmp1);
2188    AddLegalizedOperand(SDOperand(Node, 1), Tmp2);
2189    return Op.ResNo ? Tmp2 : Tmp1;
2190
2191  case ISD::STACKRESTORE:
2192    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
2193    Tmp2 = LegalizeOp(Node->getOperand(1));  // Legalize the pointer.
2194    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2);
2195
2196    switch (TLI.getOperationAction(ISD::STACKRESTORE, MVT::Other)) {
2197    default: assert(0 && "This action is not supported yet!");
2198    case TargetLowering::Legal: break;
2199    case TargetLowering::Custom:
2200      Tmp1 = TLI.LowerOperation(Result, DAG);
2201      if (Tmp1.Val) Result = Tmp1;
2202      break;
2203    case TargetLowering::Expand:
2204      // Expand to CopyToReg if the target set
2205      // StackPointerRegisterToSaveRestore.
2206      if (unsigned SP = TLI.getStackPointerRegisterToSaveRestore()) {
2207        Result = DAG.getCopyToReg(Tmp1, SP, Tmp2);
2208      } else {
2209        Result = Tmp1;
2210      }
2211      break;
2212    }
2213    break;
2214
2215  case ISD::READCYCLECOUNTER:
2216    Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain
2217    Result = DAG.UpdateNodeOperands(Result, Tmp1);
2218    switch (TLI.getOperationAction(ISD::READCYCLECOUNTER,
2219                                   Node->getValueType(0))) {
2220    default: assert(0 && "This action is not supported yet!");
2221    case TargetLowering::Legal:
2222      Tmp1 = Result.getValue(0);
2223      Tmp2 = Result.getValue(1);
2224      break;
2225    case TargetLowering::Custom:
2226      Result = TLI.LowerOperation(Result, DAG);
2227      Tmp1 = LegalizeOp(Result.getValue(0));
2228      Tmp2 = LegalizeOp(Result.getValue(1));
2229      break;
2230    }
2231
2232    // Since rdcc produce two values, make sure to remember that we legalized
2233    // both of them.
2234    AddLegalizedOperand(SDOperand(Node, 0), Tmp1);
2235    AddLegalizedOperand(SDOperand(Node, 1), Tmp2);
2236    return Result;
2237
2238  case ISD::SELECT:
2239    switch (getTypeAction(Node->getOperand(0).getValueType())) {
2240    case Expand: assert(0 && "It's impossible to expand bools");
2241    case Legal:
2242      Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the condition.
2243      break;
2244    case Promote:
2245      Tmp1 = PromoteOp(Node->getOperand(0));  // Promote the condition.
2246      // Make sure the condition is either zero or one.
2247      if (!DAG.MaskedValueIsZero(Tmp1,
2248                                 MVT::getIntVTBitMask(Tmp1.getValueType())^1))
2249        Tmp1 = DAG.getZeroExtendInReg(Tmp1, MVT::i1);
2250      break;
2251    }
2252    Tmp2 = LegalizeOp(Node->getOperand(1));   // TrueVal
2253    Tmp3 = LegalizeOp(Node->getOperand(2));   // FalseVal
2254
2255    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3);
2256
2257    switch (TLI.getOperationAction(ISD::SELECT, Tmp2.getValueType())) {
2258    default: assert(0 && "This action is not supported yet!");
2259    case TargetLowering::Legal: break;
2260    case TargetLowering::Custom: {
2261      Tmp1 = TLI.LowerOperation(Result, DAG);
2262      if (Tmp1.Val) Result = Tmp1;
2263      break;
2264    }
2265    case TargetLowering::Expand:
2266      if (Tmp1.getOpcode() == ISD::SETCC) {
2267        Result = DAG.getSelectCC(Tmp1.getOperand(0), Tmp1.getOperand(1),
2268                              Tmp2, Tmp3,
2269                              cast<CondCodeSDNode>(Tmp1.getOperand(2))->get());
2270      } else {
2271        Result = DAG.getSelectCC(Tmp1,
2272                                 DAG.getConstant(0, Tmp1.getValueType()),
2273                                 Tmp2, Tmp3, ISD::SETNE);
2274      }
2275      break;
2276    case TargetLowering::Promote: {
2277      MVT::ValueType NVT =
2278        TLI.getTypeToPromoteTo(ISD::SELECT, Tmp2.getValueType());
2279      unsigned ExtOp, TruncOp;
2280      if (MVT::isVector(Tmp2.getValueType())) {
2281        ExtOp   = ISD::BIT_CONVERT;
2282        TruncOp = ISD::BIT_CONVERT;
2283      } else if (MVT::isInteger(Tmp2.getValueType())) {
2284        ExtOp   = ISD::ANY_EXTEND;
2285        TruncOp = ISD::TRUNCATE;
2286      } else {
2287        ExtOp   = ISD::FP_EXTEND;
2288        TruncOp = ISD::FP_ROUND;
2289      }
2290      // Promote each of the values to the new type.
2291      Tmp2 = DAG.getNode(ExtOp, NVT, Tmp2);
2292      Tmp3 = DAG.getNode(ExtOp, NVT, Tmp3);
2293      // Perform the larger operation, then round down.
2294      Result = DAG.getNode(ISD::SELECT, NVT, Tmp1, Tmp2,Tmp3);
2295      Result = DAG.getNode(TruncOp, Node->getValueType(0), Result);
2296      break;
2297    }
2298    }
2299    break;
2300  case ISD::SELECT_CC: {
2301    Tmp1 = Node->getOperand(0);               // LHS
2302    Tmp2 = Node->getOperand(1);               // RHS
2303    Tmp3 = LegalizeOp(Node->getOperand(2));   // True
2304    Tmp4 = LegalizeOp(Node->getOperand(3));   // False
2305    SDOperand CC = Node->getOperand(4);
2306
2307    LegalizeSetCCOperands(Tmp1, Tmp2, CC);
2308
2309    // If we didn't get both a LHS and RHS back from LegalizeSetCCOperands,
2310    // the LHS is a legal SETCC itself.  In this case, we need to compare
2311    // the result against zero to select between true and false values.
2312    if (Tmp2.Val == 0) {
2313      Tmp2 = DAG.getConstant(0, Tmp1.getValueType());
2314      CC = DAG.getCondCode(ISD::SETNE);
2315    }
2316    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3, Tmp4, CC);
2317
2318    // Everything is legal, see if we should expand this op or something.
2319    switch (TLI.getOperationAction(ISD::SELECT_CC, Tmp3.getValueType())) {
2320    default: assert(0 && "This action is not supported yet!");
2321    case TargetLowering::Legal: break;
2322    case TargetLowering::Custom:
2323      Tmp1 = TLI.LowerOperation(Result, DAG);
2324      if (Tmp1.Val) Result = Tmp1;
2325      break;
2326    }
2327    break;
2328  }
2329  case ISD::SETCC:
2330    Tmp1 = Node->getOperand(0);
2331    Tmp2 = Node->getOperand(1);
2332    Tmp3 = Node->getOperand(2);
2333    LegalizeSetCCOperands(Tmp1, Tmp2, Tmp3);
2334
2335    // If we had to Expand the SetCC operands into a SELECT node, then it may
2336    // not always be possible to return a true LHS & RHS.  In this case, just
2337    // return the value we legalized, returned in the LHS
2338    if (Tmp2.Val == 0) {
2339      Result = Tmp1;
2340      break;
2341    }
2342
2343    switch (TLI.getOperationAction(ISD::SETCC, Tmp1.getValueType())) {
2344    default: assert(0 && "Cannot handle this action for SETCC yet!");
2345    case TargetLowering::Custom:
2346      isCustom = true;
2347      // FALLTHROUGH.
2348    case TargetLowering::Legal:
2349      Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3);
2350      if (isCustom) {
2351        Tmp4 = TLI.LowerOperation(Result, DAG);
2352        if (Tmp4.Val) Result = Tmp4;
2353      }
2354      break;
2355    case TargetLowering::Promote: {
2356      // First step, figure out the appropriate operation to use.
2357      // Allow SETCC to not be supported for all legal data types
2358      // Mostly this targets FP
2359      MVT::ValueType NewInTy = Node->getOperand(0).getValueType();
2360      MVT::ValueType OldVT = NewInTy; OldVT = OldVT;
2361
2362      // Scan for the appropriate larger type to use.
2363      while (1) {
2364        NewInTy = (MVT::ValueType)(NewInTy+1);
2365
2366        assert(MVT::isInteger(NewInTy) == MVT::isInteger(OldVT) &&
2367               "Fell off of the edge of the integer world");
2368        assert(MVT::isFloatingPoint(NewInTy) == MVT::isFloatingPoint(OldVT) &&
2369               "Fell off of the edge of the floating point world");
2370
2371        // If the target supports SETCC of this type, use it.
2372        if (TLI.isOperationLegal(ISD::SETCC, NewInTy))
2373          break;
2374      }
2375      if (MVT::isInteger(NewInTy))
2376        assert(0 && "Cannot promote Legal Integer SETCC yet");
2377      else {
2378        Tmp1 = DAG.getNode(ISD::FP_EXTEND, NewInTy, Tmp1);
2379        Tmp2 = DAG.getNode(ISD::FP_EXTEND, NewInTy, Tmp2);
2380      }
2381      Tmp1 = LegalizeOp(Tmp1);
2382      Tmp2 = LegalizeOp(Tmp2);
2383      Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3);
2384      Result = LegalizeOp(Result);
2385      break;
2386    }
2387    case TargetLowering::Expand:
2388      // Expand a setcc node into a select_cc of the same condition, lhs, and
2389      // rhs that selects between const 1 (true) and const 0 (false).
2390      MVT::ValueType VT = Node->getValueType(0);
2391      Result = DAG.getNode(ISD::SELECT_CC, VT, Tmp1, Tmp2,
2392                           DAG.getConstant(1, VT), DAG.getConstant(0, VT),
2393                           Tmp3);
2394      break;
2395    }
2396    break;
2397  case ISD::MEMSET:
2398  case ISD::MEMCPY:
2399  case ISD::MEMMOVE: {
2400    Tmp1 = LegalizeOp(Node->getOperand(0));      // Chain
2401    Tmp2 = LegalizeOp(Node->getOperand(1));      // Pointer
2402
2403    if (Node->getOpcode() == ISD::MEMSET) {      // memset = ubyte
2404      switch (getTypeAction(Node->getOperand(2).getValueType())) {
2405      case Expand: assert(0 && "Cannot expand a byte!");
2406      case Legal:
2407        Tmp3 = LegalizeOp(Node->getOperand(2));
2408        break;
2409      case Promote:
2410        Tmp3 = PromoteOp(Node->getOperand(2));
2411        break;
2412      }
2413    } else {
2414      Tmp3 = LegalizeOp(Node->getOperand(2));    // memcpy/move = pointer,
2415    }
2416
2417    SDOperand Tmp4;
2418    switch (getTypeAction(Node->getOperand(3).getValueType())) {
2419    case Expand: {
2420      // Length is too big, just take the lo-part of the length.
2421      SDOperand HiPart;
2422      ExpandOp(Node->getOperand(3), Tmp4, HiPart);
2423      break;
2424    }
2425    case Legal:
2426      Tmp4 = LegalizeOp(Node->getOperand(3));
2427      break;
2428    case Promote:
2429      Tmp4 = PromoteOp(Node->getOperand(3));
2430      break;
2431    }
2432
2433    SDOperand Tmp5;
2434    switch (getTypeAction(Node->getOperand(4).getValueType())) {  // uint
2435    case Expand: assert(0 && "Cannot expand this yet!");
2436    case Legal:
2437      Tmp5 = LegalizeOp(Node->getOperand(4));
2438      break;
2439    case Promote:
2440      Tmp5 = PromoteOp(Node->getOperand(4));
2441      break;
2442    }
2443
2444    switch (TLI.getOperationAction(Node->getOpcode(), MVT::Other)) {
2445    default: assert(0 && "This action not implemented for this operation!");
2446    case TargetLowering::Custom:
2447      isCustom = true;
2448      // FALLTHROUGH
2449    case TargetLowering::Legal:
2450      Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3, Tmp4, Tmp5);
2451      if (isCustom) {
2452        Tmp1 = TLI.LowerOperation(Result, DAG);
2453        if (Tmp1.Val) Result = Tmp1;
2454      }
2455      break;
2456    case TargetLowering::Expand: {
2457      // Otherwise, the target does not support this operation.  Lower the
2458      // operation to an explicit libcall as appropriate.
2459      MVT::ValueType IntPtr = TLI.getPointerTy();
2460      const Type *IntPtrTy = TLI.getTargetData()->getIntPtrType();
2461      TargetLowering::ArgListTy Args;
2462      TargetLowering::ArgListEntry Entry;
2463
2464      const char *FnName = 0;
2465      if (Node->getOpcode() == ISD::MEMSET) {
2466        Entry.Node = Tmp2; Entry.Ty = IntPtrTy;
2467        Args.push_back(Entry);
2468        // Extend the (previously legalized) ubyte argument to be an int value
2469        // for the call.
2470        if (Tmp3.getValueType() > MVT::i32)
2471          Tmp3 = DAG.getNode(ISD::TRUNCATE, MVT::i32, Tmp3);
2472        else
2473          Tmp3 = DAG.getNode(ISD::ZERO_EXTEND, MVT::i32, Tmp3);
2474        Entry.Node = Tmp3; Entry.Ty = Type::Int32Ty; Entry.isSExt = true;
2475        Args.push_back(Entry);
2476        Entry.Node = Tmp4; Entry.Ty = IntPtrTy; Entry.isSExt = false;
2477        Args.push_back(Entry);
2478
2479        FnName = "memset";
2480      } else if (Node->getOpcode() == ISD::MEMCPY ||
2481                 Node->getOpcode() == ISD::MEMMOVE) {
2482        Entry.Ty = IntPtrTy;
2483        Entry.Node = Tmp2; Args.push_back(Entry);
2484        Entry.Node = Tmp3; Args.push_back(Entry);
2485        Entry.Node = Tmp4; Args.push_back(Entry);
2486        FnName = Node->getOpcode() == ISD::MEMMOVE ? "memmove" : "memcpy";
2487      } else {
2488        assert(0 && "Unknown op!");
2489      }
2490
2491      std::pair<SDOperand,SDOperand> CallResult =
2492        TLI.LowerCallTo(Tmp1, Type::VoidTy, false, false, CallingConv::C, false,
2493                        DAG.getExternalSymbol(FnName, IntPtr), Args, DAG);
2494      Result = CallResult.second;
2495      break;
2496    }
2497    }
2498    break;
2499  }
2500
2501  case ISD::SHL_PARTS:
2502  case ISD::SRA_PARTS:
2503  case ISD::SRL_PARTS: {
2504    SmallVector<SDOperand, 8> Ops;
2505    bool Changed = false;
2506    for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
2507      Ops.push_back(LegalizeOp(Node->getOperand(i)));
2508      Changed |= Ops.back() != Node->getOperand(i);
2509    }
2510    if (Changed)
2511      Result = DAG.UpdateNodeOperands(Result, &Ops[0], Ops.size());
2512
2513    switch (TLI.getOperationAction(Node->getOpcode(),
2514                                   Node->getValueType(0))) {
2515    default: assert(0 && "This action is not supported yet!");
2516    case TargetLowering::Legal: break;
2517    case TargetLowering::Custom:
2518      Tmp1 = TLI.LowerOperation(Result, DAG);
2519      if (Tmp1.Val) {
2520        SDOperand Tmp2, RetVal(0, 0);
2521        for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i) {
2522          Tmp2 = LegalizeOp(Tmp1.getValue(i));
2523          AddLegalizedOperand(SDOperand(Node, i), Tmp2);
2524          if (i == Op.ResNo)
2525            RetVal = Tmp2;
2526        }
2527        assert(RetVal.Val && "Illegal result number");
2528        return RetVal;
2529      }
2530      break;
2531    }
2532
2533    // Since these produce multiple values, make sure to remember that we
2534    // legalized all of them.
2535    for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
2536      AddLegalizedOperand(SDOperand(Node, i), Result.getValue(i));
2537    return Result.getValue(Op.ResNo);
2538  }
2539
2540    // Binary operators
2541  case ISD::ADD:
2542  case ISD::SUB:
2543  case ISD::MUL:
2544  case ISD::MULHS:
2545  case ISD::MULHU:
2546  case ISD::UDIV:
2547  case ISD::SDIV:
2548  case ISD::AND:
2549  case ISD::OR:
2550  case ISD::XOR:
2551  case ISD::SHL:
2552  case ISD::SRL:
2553  case ISD::SRA:
2554  case ISD::FADD:
2555  case ISD::FSUB:
2556  case ISD::FMUL:
2557  case ISD::FDIV:
2558    Tmp1 = LegalizeOp(Node->getOperand(0));   // LHS
2559    switch (getTypeAction(Node->getOperand(1).getValueType())) {
2560    case Expand: assert(0 && "Not possible");
2561    case Legal:
2562      Tmp2 = LegalizeOp(Node->getOperand(1)); // Legalize the RHS.
2563      break;
2564    case Promote:
2565      Tmp2 = PromoteOp(Node->getOperand(1));  // Promote the RHS.
2566      break;
2567    }
2568
2569    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2);
2570
2571    switch (TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0))) {
2572    default: assert(0 && "BinOp legalize operation not supported");
2573    case TargetLowering::Legal: break;
2574    case TargetLowering::Custom:
2575      Tmp1 = TLI.LowerOperation(Result, DAG);
2576      if (Tmp1.Val) Result = Tmp1;
2577      break;
2578    case TargetLowering::Expand: {
2579      if (Node->getValueType(0) == MVT::i32) {
2580        switch (Node->getOpcode()) {
2581        default:  assert(0 && "Do not know how to expand this integer BinOp!");
2582        case ISD::UDIV:
2583        case ISD::SDIV:
2584          RTLIB::Libcall LC = Node->getOpcode() == ISD::UDIV
2585            ? RTLIB::UDIV_I32 : RTLIB::SDIV_I32;
2586          SDOperand Dummy;
2587          bool isSigned = Node->getOpcode() == ISD::SDIV;
2588          Result = ExpandLibCall(TLI.getLibcallName(LC), Node, isSigned, Dummy);
2589        };
2590        break;
2591      }
2592
2593      assert(MVT::isVector(Node->getValueType(0)) &&
2594             "Cannot expand this binary operator!");
2595      // Expand the operation into a bunch of nasty scalar code.
2596      SmallVector<SDOperand, 8> Ops;
2597      MVT::ValueType EltVT = MVT::getVectorElementType(Node->getValueType(0));
2598      MVT::ValueType PtrVT = TLI.getPointerTy();
2599      for (unsigned i = 0, e = MVT::getVectorNumElements(Node->getValueType(0));
2600           i != e; ++i) {
2601        SDOperand Idx = DAG.getConstant(i, PtrVT);
2602        SDOperand LHS = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, EltVT, Tmp1, Idx);
2603        SDOperand RHS = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, EltVT, Tmp2, Idx);
2604        Ops.push_back(DAG.getNode(Node->getOpcode(), EltVT, LHS, RHS));
2605      }
2606      Result = DAG.getNode(ISD::BUILD_VECTOR, Node->getValueType(0),
2607                           &Ops[0], Ops.size());
2608      break;
2609    }
2610    case TargetLowering::Promote: {
2611      switch (Node->getOpcode()) {
2612      default:  assert(0 && "Do not know how to promote this BinOp!");
2613      case ISD::AND:
2614      case ISD::OR:
2615      case ISD::XOR: {
2616        MVT::ValueType OVT = Node->getValueType(0);
2617        MVT::ValueType NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), OVT);
2618        assert(MVT::isVector(OVT) && "Cannot promote this BinOp!");
2619        // Bit convert each of the values to the new type.
2620        Tmp1 = DAG.getNode(ISD::BIT_CONVERT, NVT, Tmp1);
2621        Tmp2 = DAG.getNode(ISD::BIT_CONVERT, NVT, Tmp2);
2622        Result = DAG.getNode(Node->getOpcode(), NVT, Tmp1, Tmp2);
2623        // Bit convert the result back the original type.
2624        Result = DAG.getNode(ISD::BIT_CONVERT, OVT, Result);
2625        break;
2626      }
2627      }
2628    }
2629    }
2630    break;
2631
2632  case ISD::FCOPYSIGN:  // FCOPYSIGN does not require LHS/RHS to match type!
2633    Tmp1 = LegalizeOp(Node->getOperand(0));   // LHS
2634    switch (getTypeAction(Node->getOperand(1).getValueType())) {
2635      case Expand: assert(0 && "Not possible");
2636      case Legal:
2637        Tmp2 = LegalizeOp(Node->getOperand(1)); // Legalize the RHS.
2638        break;
2639      case Promote:
2640        Tmp2 = PromoteOp(Node->getOperand(1));  // Promote the RHS.
2641        break;
2642    }
2643
2644    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2);
2645
2646    switch (TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0))) {
2647    default: assert(0 && "Operation not supported");
2648    case TargetLowering::Custom:
2649      Tmp1 = TLI.LowerOperation(Result, DAG);
2650      if (Tmp1.Val) Result = Tmp1;
2651      break;
2652    case TargetLowering::Legal: break;
2653    case TargetLowering::Expand: {
2654      // If this target supports fabs/fneg natively and select is cheap,
2655      // do this efficiently.
2656      if (!TLI.isSelectExpensive() &&
2657          TLI.getOperationAction(ISD::FABS, Tmp1.getValueType()) ==
2658          TargetLowering::Legal &&
2659          TLI.getOperationAction(ISD::FNEG, Tmp1.getValueType()) ==
2660          TargetLowering::Legal) {
2661        // Get the sign bit of the RHS.
2662        MVT::ValueType IVT =
2663          Tmp2.getValueType() == MVT::f32 ? MVT::i32 : MVT::i64;
2664        SDOperand SignBit = DAG.getNode(ISD::BIT_CONVERT, IVT, Tmp2);
2665        SignBit = DAG.getSetCC(TLI.getSetCCResultTy(),
2666                               SignBit, DAG.getConstant(0, IVT), ISD::SETLT);
2667        // Get the absolute value of the result.
2668        SDOperand AbsVal = DAG.getNode(ISD::FABS, Tmp1.getValueType(), Tmp1);
2669        // Select between the nabs and abs value based on the sign bit of
2670        // the input.
2671        Result = DAG.getNode(ISD::SELECT, AbsVal.getValueType(), SignBit,
2672                             DAG.getNode(ISD::FNEG, AbsVal.getValueType(),
2673                                         AbsVal),
2674                             AbsVal);
2675        Result = LegalizeOp(Result);
2676        break;
2677      }
2678
2679      // Otherwise, do bitwise ops!
2680      MVT::ValueType NVT =
2681        Node->getValueType(0) == MVT::f32 ? MVT::i32 : MVT::i64;
2682      Result = ExpandFCOPYSIGNToBitwiseOps(Node, NVT, DAG, TLI);
2683      Result = DAG.getNode(ISD::BIT_CONVERT, Node->getValueType(0), Result);
2684      Result = LegalizeOp(Result);
2685      break;
2686    }
2687    }
2688    break;
2689
2690  case ISD::ADDC:
2691  case ISD::SUBC:
2692    Tmp1 = LegalizeOp(Node->getOperand(0));
2693    Tmp2 = LegalizeOp(Node->getOperand(1));
2694    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2);
2695    // Since this produces two values, make sure to remember that we legalized
2696    // both of them.
2697    AddLegalizedOperand(SDOperand(Node, 0), Result.getValue(0));
2698    AddLegalizedOperand(SDOperand(Node, 1), Result.getValue(1));
2699    return Result;
2700
2701  case ISD::ADDE:
2702  case ISD::SUBE:
2703    Tmp1 = LegalizeOp(Node->getOperand(0));
2704    Tmp2 = LegalizeOp(Node->getOperand(1));
2705    Tmp3 = LegalizeOp(Node->getOperand(2));
2706    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3);
2707    // Since this produces two values, make sure to remember that we legalized
2708    // both of them.
2709    AddLegalizedOperand(SDOperand(Node, 0), Result.getValue(0));
2710    AddLegalizedOperand(SDOperand(Node, 1), Result.getValue(1));
2711    return Result;
2712
2713  case ISD::BUILD_PAIR: {
2714    MVT::ValueType PairTy = Node->getValueType(0);
2715    // TODO: handle the case where the Lo and Hi operands are not of legal type
2716    Tmp1 = LegalizeOp(Node->getOperand(0));   // Lo
2717    Tmp2 = LegalizeOp(Node->getOperand(1));   // Hi
2718    switch (TLI.getOperationAction(ISD::BUILD_PAIR, PairTy)) {
2719    case TargetLowering::Promote:
2720    case TargetLowering::Custom:
2721      assert(0 && "Cannot promote/custom this yet!");
2722    case TargetLowering::Legal:
2723      if (Tmp1 != Node->getOperand(0) || Tmp2 != Node->getOperand(1))
2724        Result = DAG.getNode(ISD::BUILD_PAIR, PairTy, Tmp1, Tmp2);
2725      break;
2726    case TargetLowering::Expand:
2727      Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, PairTy, Tmp1);
2728      Tmp2 = DAG.getNode(ISD::ANY_EXTEND, PairTy, Tmp2);
2729      Tmp2 = DAG.getNode(ISD::SHL, PairTy, Tmp2,
2730                         DAG.getConstant(MVT::getSizeInBits(PairTy)/2,
2731                                         TLI.getShiftAmountTy()));
2732      Result = DAG.getNode(ISD::OR, PairTy, Tmp1, Tmp2);
2733      break;
2734    }
2735    break;
2736  }
2737
2738  case ISD::UREM:
2739  case ISD::SREM:
2740  case ISD::FREM:
2741    Tmp1 = LegalizeOp(Node->getOperand(0));   // LHS
2742    Tmp2 = LegalizeOp(Node->getOperand(1));   // RHS
2743
2744    switch (TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0))) {
2745    case TargetLowering::Promote: assert(0 && "Cannot promote this yet!");
2746    case TargetLowering::Custom:
2747      isCustom = true;
2748      // FALLTHROUGH
2749    case TargetLowering::Legal:
2750      Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2);
2751      if (isCustom) {
2752        Tmp1 = TLI.LowerOperation(Result, DAG);
2753        if (Tmp1.Val) Result = Tmp1;
2754      }
2755      break;
2756    case TargetLowering::Expand:
2757      unsigned DivOpc= (Node->getOpcode() == ISD::UREM) ? ISD::UDIV : ISD::SDIV;
2758      bool isSigned = DivOpc == ISD::SDIV;
2759      if (MVT::isInteger(Node->getValueType(0))) {
2760        if (TLI.getOperationAction(DivOpc, Node->getValueType(0)) ==
2761            TargetLowering::Legal) {
2762          // X % Y -> X-X/Y*Y
2763          MVT::ValueType VT = Node->getValueType(0);
2764          Result = DAG.getNode(DivOpc, VT, Tmp1, Tmp2);
2765          Result = DAG.getNode(ISD::MUL, VT, Result, Tmp2);
2766          Result = DAG.getNode(ISD::SUB, VT, Tmp1, Result);
2767        } else {
2768          assert(Node->getValueType(0) == MVT::i32 &&
2769                 "Cannot expand this binary operator!");
2770          RTLIB::Libcall LC = Node->getOpcode() == ISD::UREM
2771            ? RTLIB::UREM_I32 : RTLIB::SREM_I32;
2772          SDOperand Dummy;
2773          Result = ExpandLibCall(TLI.getLibcallName(LC), Node, isSigned, Dummy);
2774        }
2775      } else {
2776        // Floating point mod -> fmod libcall.
2777        RTLIB::Libcall LC = Node->getValueType(0) == MVT::f32
2778          ? RTLIB::REM_F32 : RTLIB::REM_F64;
2779        SDOperand Dummy;
2780        Result = ExpandLibCall(TLI.getLibcallName(LC), Node,
2781                               false/*sign irrelevant*/, Dummy);
2782      }
2783      break;
2784    }
2785    break;
2786  case ISD::VAARG: {
2787    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
2788    Tmp2 = LegalizeOp(Node->getOperand(1));  // Legalize the pointer.
2789
2790    MVT::ValueType VT = Node->getValueType(0);
2791    switch (TLI.getOperationAction(Node->getOpcode(), MVT::Other)) {
2792    default: assert(0 && "This action is not supported yet!");
2793    case TargetLowering::Custom:
2794      isCustom = true;
2795      // FALLTHROUGH
2796    case TargetLowering::Legal:
2797      Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Node->getOperand(2));
2798      Result = Result.getValue(0);
2799      Tmp1 = Result.getValue(1);
2800
2801      if (isCustom) {
2802        Tmp2 = TLI.LowerOperation(Result, DAG);
2803        if (Tmp2.Val) {
2804          Result = LegalizeOp(Tmp2);
2805          Tmp1 = LegalizeOp(Tmp2.getValue(1));
2806        }
2807      }
2808      break;
2809    case TargetLowering::Expand: {
2810      SrcValueSDNode *SV = cast<SrcValueSDNode>(Node->getOperand(2));
2811      SDOperand VAList = DAG.getLoad(TLI.getPointerTy(), Tmp1, Tmp2,
2812                                     SV->getValue(), SV->getOffset());
2813      // Increment the pointer, VAList, to the next vaarg
2814      Tmp3 = DAG.getNode(ISD::ADD, TLI.getPointerTy(), VAList,
2815                         DAG.getConstant(MVT::getSizeInBits(VT)/8,
2816                                         TLI.getPointerTy()));
2817      // Store the incremented VAList to the legalized pointer
2818      Tmp3 = DAG.getStore(VAList.getValue(1), Tmp3, Tmp2, SV->getValue(),
2819                          SV->getOffset());
2820      // Load the actual argument out of the pointer VAList
2821      Result = DAG.getLoad(VT, Tmp3, VAList, NULL, 0);
2822      Tmp1 = LegalizeOp(Result.getValue(1));
2823      Result = LegalizeOp(Result);
2824      break;
2825    }
2826    }
2827    // Since VAARG produces two values, make sure to remember that we
2828    // legalized both of them.
2829    AddLegalizedOperand(SDOperand(Node, 0), Result);
2830    AddLegalizedOperand(SDOperand(Node, 1), Tmp1);
2831    return Op.ResNo ? Tmp1 : Result;
2832  }
2833
2834  case ISD::VACOPY:
2835    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
2836    Tmp2 = LegalizeOp(Node->getOperand(1));  // Legalize the dest pointer.
2837    Tmp3 = LegalizeOp(Node->getOperand(2));  // Legalize the source pointer.
2838
2839    switch (TLI.getOperationAction(ISD::VACOPY, MVT::Other)) {
2840    default: assert(0 && "This action is not supported yet!");
2841    case TargetLowering::Custom:
2842      isCustom = true;
2843      // FALLTHROUGH
2844    case TargetLowering::Legal:
2845      Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Tmp3,
2846                                      Node->getOperand(3), Node->getOperand(4));
2847      if (isCustom) {
2848        Tmp1 = TLI.LowerOperation(Result, DAG);
2849        if (Tmp1.Val) Result = Tmp1;
2850      }
2851      break;
2852    case TargetLowering::Expand:
2853      // This defaults to loading a pointer from the input and storing it to the
2854      // output, returning the chain.
2855      SrcValueSDNode *SVD = cast<SrcValueSDNode>(Node->getOperand(3));
2856      SrcValueSDNode *SVS = cast<SrcValueSDNode>(Node->getOperand(4));
2857      Tmp4 = DAG.getLoad(TLI.getPointerTy(), Tmp1, Tmp3, SVD->getValue(),
2858                         SVD->getOffset());
2859      Result = DAG.getStore(Tmp4.getValue(1), Tmp4, Tmp2, SVS->getValue(),
2860                            SVS->getOffset());
2861      break;
2862    }
2863    break;
2864
2865  case ISD::VAEND:
2866    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
2867    Tmp2 = LegalizeOp(Node->getOperand(1));  // Legalize the pointer.
2868
2869    switch (TLI.getOperationAction(ISD::VAEND, MVT::Other)) {
2870    default: assert(0 && "This action is not supported yet!");
2871    case TargetLowering::Custom:
2872      isCustom = true;
2873      // FALLTHROUGH
2874    case TargetLowering::Legal:
2875      Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Node->getOperand(2));
2876      if (isCustom) {
2877        Tmp1 = TLI.LowerOperation(Tmp1, DAG);
2878        if (Tmp1.Val) Result = Tmp1;
2879      }
2880      break;
2881    case TargetLowering::Expand:
2882      Result = Tmp1; // Default to a no-op, return the chain
2883      break;
2884    }
2885    break;
2886
2887  case ISD::VASTART:
2888    Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
2889    Tmp2 = LegalizeOp(Node->getOperand(1));  // Legalize the pointer.
2890
2891    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Node->getOperand(2));
2892
2893    switch (TLI.getOperationAction(ISD::VASTART, MVT::Other)) {
2894    default: assert(0 && "This action is not supported yet!");
2895    case TargetLowering::Legal: break;
2896    case TargetLowering::Custom:
2897      Tmp1 = TLI.LowerOperation(Result, DAG);
2898      if (Tmp1.Val) Result = Tmp1;
2899      break;
2900    }
2901    break;
2902
2903  case ISD::ROTL:
2904  case ISD::ROTR:
2905    Tmp1 = LegalizeOp(Node->getOperand(0));   // LHS
2906    Tmp2 = LegalizeOp(Node->getOperand(1));   // RHS
2907    Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2);
2908    switch (TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0))) {
2909    default:
2910      assert(0 && "ROTL/ROTR legalize operation not supported");
2911      break;
2912    case TargetLowering::Legal:
2913      break;
2914    case TargetLowering::Custom:
2915      Tmp1 = TLI.LowerOperation(Result, DAG);
2916      if (Tmp1.Val) Result = Tmp1;
2917      break;
2918    case TargetLowering::Promote:
2919      assert(0 && "Do not know how to promote ROTL/ROTR");
2920      break;
2921    case TargetLowering::Expand:
2922      assert(0 && "Do not know how to expand ROTL/ROTR");
2923      break;
2924    }
2925    break;
2926
2927  case ISD::BSWAP:
2928    Tmp1 = LegalizeOp(Node->getOperand(0));   // Op
2929    switch (TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0))) {
2930    case TargetLowering::Custom:
2931      assert(0 && "Cannot custom legalize this yet!");
2932    case TargetLowering::Legal:
2933      Result = DAG.UpdateNodeOperands(Result, Tmp1);
2934      break;
2935    case TargetLowering::Promote: {
2936      MVT::ValueType OVT = Tmp1.getValueType();
2937      MVT::ValueType NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), OVT);
2938      unsigned DiffBits = MVT::getSizeInBits(NVT) - MVT::getSizeInBits(OVT);
2939
2940      Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, NVT, Tmp1);
2941      Tmp1 = DAG.getNode(ISD::BSWAP, NVT, Tmp1);
2942      Result = DAG.getNode(ISD::SRL, NVT, Tmp1,
2943                           DAG.getConstant(DiffBits, TLI.getShiftAmountTy()));
2944      break;
2945    }
2946    case TargetLowering::Expand:
2947      Result = ExpandBSWAP(Tmp1);
2948      break;
2949    }
2950    break;
2951
2952  case ISD::CTPOP:
2953  case ISD::CTTZ:
2954  case ISD::CTLZ:
2955    Tmp1 = LegalizeOp(Node->getOperand(0));   // Op
2956    switch (TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0))) {
2957    case TargetLowering::Custom:
2958    case TargetLowering::Legal:
2959      Result = DAG.UpdateNodeOperands(Result, Tmp1);
2960      if (TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0)) ==
2961          TargetLowering::Custom) {
2962        Tmp1 = TLI.LowerOperation(Result, DAG);
2963        if (Tmp1.Val) {
2964          Result = Tmp1;
2965        }
2966      }
2967      break;
2968    case TargetLowering::Promote: {
2969      MVT::ValueType OVT = Tmp1.getValueType();
2970      MVT::ValueType NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), OVT);
2971
2972      // Zero extend the argument.
2973      Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, NVT, Tmp1);
2974      // Perform the larger operation, then subtract if needed.
2975      Tmp1 = DAG.getNode(Node->getOpcode(), Node->getValueType(0), Tmp1);
2976      switch (Node->getOpcode()) {
2977      case ISD::CTPOP:
2978        Result = Tmp1;
2979        break;
2980      case ISD::CTTZ:
2981        //if Tmp1 == sizeinbits(NVT) then Tmp1 = sizeinbits(Old VT)
2982        Tmp2 = DAG.getSetCC(TLI.getSetCCResultTy(), Tmp1,
2983                            DAG.getConstant(MVT::getSizeInBits(NVT), NVT),
2984                            ISD::SETEQ);
2985        Result = DAG.getNode(ISD::SELECT, NVT, Tmp2,
2986                             DAG.getConstant(MVT::getSizeInBits(OVT),NVT), Tmp1);
2987        break;
2988      case ISD::CTLZ:
2989        // Tmp1 = Tmp1 - (sizeinbits(NVT) - sizeinbits(Old VT))
2990        Result = DAG.getNode(ISD::SUB, NVT, Tmp1,
2991                             DAG.getConstant(MVT::getSizeInBits(NVT) -
2992                                             MVT::getSizeInBits(OVT), NVT));
2993        break;
2994      }
2995      break;
2996    }
2997    case TargetLowering::Expand:
2998      Result = ExpandBitCount(Node->getOpcode(), Tmp1);
2999      break;
3000    }
3001    break;
3002
3003    // Unary operators
3004  case ISD::FABS:
3005  case ISD::FNEG:
3006  case ISD::FSQRT:
3007  case ISD::FSIN:
3008  case ISD::FCOS:
3009    Tmp1 = LegalizeOp(Node->getOperand(0));
3010    switch (TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0))) {
3011    case TargetLowering::Promote:
3012    case TargetLowering::Custom:
3013     isCustom = true;
3014     // FALLTHROUGH
3015    case TargetLowering::Legal:
3016      Result = DAG.UpdateNodeOperands(Result, Tmp1);
3017      if (isCustom) {
3018        Tmp1 = TLI.LowerOperation(Result, DAG);
3019        if (Tmp1.Val) Result = Tmp1;
3020      }
3021      break;
3022    case TargetLowering::Expand:
3023      switch (Node->getOpcode()) {
3024      default: assert(0 && "Unreachable!");
3025      case ISD::FNEG:
3026        // Expand Y = FNEG(X) ->  Y = SUB -0.0, X
3027        Tmp2 = DAG.getConstantFP(-0.0, Node->getValueType(0));
3028        Result = DAG.getNode(ISD::FSUB, Node->getValueType(0), Tmp2, Tmp1);
3029        break;
3030      case ISD::FABS: {
3031        // Expand Y = FABS(X) -> Y = (X >u 0.0) ? X : fneg(X).
3032        MVT::ValueType VT = Node->getValueType(0);
3033        Tmp2 = DAG.getConstantFP(0.0, VT);
3034        Tmp2 = DAG.getSetCC(TLI.getSetCCResultTy(), Tmp1, Tmp2, ISD::SETUGT);
3035        Tmp3 = DAG.getNode(ISD::FNEG, VT, Tmp1);
3036        Result = DAG.getNode(ISD::SELECT, VT, Tmp2, Tmp1, Tmp3);
3037        break;
3038      }
3039      case ISD::FSQRT:
3040      case ISD::FSIN:
3041      case ISD::FCOS: {
3042        MVT::ValueType VT = Node->getValueType(0);
3043        RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
3044        switch(Node->getOpcode()) {
3045        case ISD::FSQRT:
3046          LC = VT == MVT::f32 ? RTLIB::SQRT_F32 : RTLIB::SQRT_F64;
3047          break;
3048        case ISD::FSIN:
3049          LC = VT == MVT::f32 ? RTLIB::SIN_F32 : RTLIB::SIN_F64;
3050          break;
3051        case ISD::FCOS:
3052          LC = VT == MVT::f32 ? RTLIB::COS_F32 : RTLIB::COS_F64;
3053          break;
3054        default: assert(0 && "Unreachable!");
3055        }
3056        SDOperand Dummy;
3057        Result = ExpandLibCall(TLI.getLibcallName(LC), Node,
3058                               false/*sign irrelevant*/, Dummy);
3059        break;
3060      }
3061      }
3062      break;
3063    }
3064    break;
3065  case ISD::FPOWI: {
3066    // We always lower FPOWI into a libcall.  No target support it yet.
3067    RTLIB::Libcall LC = Node->getValueType(0) == MVT::f32
3068      ? RTLIB::POWI_F32 : RTLIB::POWI_F64;
3069    SDOperand Dummy;
3070    Result = ExpandLibCall(TLI.getLibcallName(LC), Node,
3071                           false/*sign irrelevant*/, Dummy);
3072    break;
3073  }
3074  case ISD::BIT_CONVERT:
3075    if (!isTypeLegal(Node->getOperand(0).getValueType())) {
3076      Result = ExpandBIT_CONVERT(Node->getValueType(0), Node->getOperand(0));
3077    } else if (MVT::isVector(Op.getOperand(0).getValueType())) {
3078      // The input has to be a vector type, we have to either scalarize it, pack
3079      // it, or convert it based on whether the input vector type is legal.
3080      SDNode *InVal = Node->getOperand(0).Val;
3081      unsigned NumElems = MVT::getVectorNumElements(InVal->getValueType(0));
3082      MVT::ValueType EVT = MVT::getVectorElementType(InVal->getValueType(0));
3083
3084      // Figure out if there is a simple type corresponding to this Vector
3085      // type.  If so, convert to the vector type.
3086      MVT::ValueType TVT = MVT::getVectorType(EVT, NumElems);
3087      if (TLI.isTypeLegal(TVT)) {
3088        // Turn this into a bit convert of the vector input.
3089        Result = DAG.getNode(ISD::BIT_CONVERT, Node->getValueType(0),
3090                             LegalizeOp(Node->getOperand(0)));
3091        break;
3092      } else if (NumElems == 1) {
3093        // Turn this into a bit convert of the scalar input.
3094        Result = DAG.getNode(ISD::BIT_CONVERT, Node->getValueType(0),
3095                             ScalarizeVectorOp(Node->getOperand(0)));
3096        break;
3097      } else {
3098        // FIXME: UNIMP!  Store then reload
3099        assert(0 && "Cast from unsupported vector type not implemented yet!");
3100      }
3101    } else {
3102      switch (TLI.getOperationAction(ISD::BIT_CONVERT,
3103                                     Node->getOperand(0).getValueType())) {
3104      default: assert(0 && "Unknown operation action!");
3105      case TargetLowering::Expand:
3106        Result = ExpandBIT_CONVERT(Node->getValueType(0), Node->getOperand(0));
3107        break;
3108      case TargetLowering::Legal:
3109        Tmp1 = LegalizeOp(Node->getOperand(0));
3110        Result = DAG.UpdateNodeOperands(Result, Tmp1);
3111        break;
3112      }
3113    }
3114    break;
3115
3116    // Conversion operators.  The source and destination have different types.
3117  case ISD::SINT_TO_FP:
3118  case ISD::UINT_TO_FP: {
3119    bool isSigned = Node->getOpcode() == ISD::SINT_TO_FP;
3120    switch (getTypeAction(Node->getOperand(0).getValueType())) {
3121    case Legal:
3122      switch (TLI.getOperationAction(Node->getOpcode(),
3123                                     Node->getOperand(0).getValueType())) {
3124      default: assert(0 && "Unknown operation action!");
3125      case TargetLowering::Custom:
3126        isCustom = true;
3127        // FALLTHROUGH
3128      case TargetLowering::Legal:
3129        Tmp1 = LegalizeOp(Node->getOperand(0));
3130        Result = DAG.UpdateNodeOperands(Result, Tmp1);
3131        if (isCustom) {
3132          Tmp1 = TLI.LowerOperation(Result, DAG);
3133          if (Tmp1.Val) Result = Tmp1;
3134        }
3135        break;
3136      case TargetLowering::Expand:
3137        Result = ExpandLegalINT_TO_FP(isSigned,
3138                                      LegalizeOp(Node->getOperand(0)),
3139                                      Node->getValueType(0));
3140        break;
3141      case TargetLowering::Promote:
3142        Result = PromoteLegalINT_TO_FP(LegalizeOp(Node->getOperand(0)),
3143                                       Node->getValueType(0),
3144                                       isSigned);
3145        break;
3146      }
3147      break;
3148    case Expand:
3149      Result = ExpandIntToFP(Node->getOpcode() == ISD::SINT_TO_FP,
3150                             Node->getValueType(0), Node->getOperand(0));
3151      break;
3152    case Promote:
3153      Tmp1 = PromoteOp(Node->getOperand(0));
3154      if (isSigned) {
3155        Tmp1 = DAG.getNode(ISD::SIGN_EXTEND_INREG, Tmp1.getValueType(),
3156                 Tmp1, DAG.getValueType(Node->getOperand(0).getValueType()));
3157      } else {
3158        Tmp1 = DAG.getZeroExtendInReg(Tmp1,
3159                                      Node->getOperand(0).getValueType());
3160      }
3161      Result = DAG.UpdateNodeOperands(Result, Tmp1);
3162      Result = LegalizeOp(Result);  // The 'op' is not necessarily legal!
3163      break;
3164    }
3165    break;
3166  }
3167  case ISD::TRUNCATE:
3168    switch (getTypeAction(Node->getOperand(0).getValueType())) {
3169    case Legal:
3170      Tmp1 = LegalizeOp(Node->getOperand(0));
3171      Result = DAG.UpdateNodeOperands(Result, Tmp1);
3172      break;
3173    case Expand:
3174      ExpandOp(Node->getOperand(0), Tmp1, Tmp2);
3175
3176      // Since the result is legal, we should just be able to truncate the low
3177      // part of the source.
3178      Result = DAG.getNode(ISD::TRUNCATE, Node->getValueType(0), Tmp1);
3179      break;
3180    case Promote:
3181      Result = PromoteOp(Node->getOperand(0));
3182      Result = DAG.getNode(ISD::TRUNCATE, Op.getValueType(), Result);
3183      break;
3184    }
3185    break;
3186
3187  case ISD::FP_TO_SINT:
3188  case ISD::FP_TO_UINT:
3189    switch (getTypeAction(Node->getOperand(0).getValueType())) {
3190    case Legal:
3191      Tmp1 = LegalizeOp(Node->getOperand(0));
3192
3193      switch (TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0))){
3194      default: assert(0 && "Unknown operation action!");
3195      case TargetLowering::Custom:
3196        isCustom = true;
3197        // FALLTHROUGH
3198      case TargetLowering::Legal:
3199        Result = DAG.UpdateNodeOperands(Result, Tmp1);
3200        if (isCustom) {
3201          Tmp1 = TLI.LowerOperation(Result, DAG);
3202          if (Tmp1.Val) Result = Tmp1;
3203        }
3204        break;
3205      case TargetLowering::Promote:
3206        Result = PromoteLegalFP_TO_INT(Tmp1, Node->getValueType(0),
3207                                       Node->getOpcode() == ISD::FP_TO_SINT);
3208        break;
3209      case TargetLowering::Expand:
3210        if (Node->getOpcode() == ISD::FP_TO_UINT) {
3211          SDOperand True, False;
3212          MVT::ValueType VT =  Node->getOperand(0).getValueType();
3213          MVT::ValueType NVT = Node->getValueType(0);
3214          unsigned ShiftAmt = MVT::getSizeInBits(Node->getValueType(0))-1;
3215          Tmp2 = DAG.getConstantFP((double)(1ULL << ShiftAmt), VT);
3216          Tmp3 = DAG.getSetCC(TLI.getSetCCResultTy(),
3217                            Node->getOperand(0), Tmp2, ISD::SETLT);
3218          True = DAG.getNode(ISD::FP_TO_SINT, NVT, Node->getOperand(0));
3219          False = DAG.getNode(ISD::FP_TO_SINT, NVT,
3220                              DAG.getNode(ISD::FSUB, VT, Node->getOperand(0),
3221                                          Tmp2));
3222          False = DAG.getNode(ISD::XOR, NVT, False,
3223                              DAG.getConstant(1ULL << ShiftAmt, NVT));
3224          Result = DAG.getNode(ISD::SELECT, NVT, Tmp3, True, False);
3225          break;
3226        } else {
3227          assert(0 && "Do not know how to expand FP_TO_SINT yet!");
3228        }
3229        break;
3230      }
3231      break;
3232    case Expand: {
3233      // Convert f32 / f64 to i32 / i64.
3234      MVT::ValueType VT = Op.getValueType();
3235      RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
3236      switch (Node->getOpcode()) {
3237      case ISD::FP_TO_SINT:
3238        if (Node->getOperand(0).getValueType() == MVT::f32)
3239          LC = (VT == MVT::i32)
3240            ? RTLIB::FPTOSINT_F32_I32 : RTLIB::FPTOSINT_F32_I64;
3241        else
3242          LC = (VT == MVT::i32)
3243            ? RTLIB::FPTOSINT_F64_I32 : RTLIB::FPTOSINT_F64_I64;
3244        break;
3245      case ISD::FP_TO_UINT:
3246        if (Node->getOperand(0).getValueType() == MVT::f32)
3247          LC = (VT == MVT::i32)
3248            ? RTLIB::FPTOUINT_F32_I32 : RTLIB::FPTOSINT_F32_I64;
3249        else
3250          LC = (VT == MVT::i32)
3251            ? RTLIB::FPTOUINT_F64_I32 : RTLIB::FPTOSINT_F64_I64;
3252        break;
3253      default: assert(0 && "Unreachable!");
3254      }
3255      SDOperand Dummy;
3256      Result = ExpandLibCall(TLI.getLibcallName(LC), Node,
3257                             false/*sign irrelevant*/, Dummy);
3258      break;
3259    }
3260    case Promote:
3261      Tmp1 = PromoteOp(Node->getOperand(0));
3262      Result = DAG.UpdateNodeOperands(Result, LegalizeOp(Tmp1));
3263      Result = LegalizeOp(Result);
3264      break;
3265    }
3266    break;
3267
3268  case ISD::FP_EXTEND:
3269  case ISD::FP_ROUND: {
3270      MVT::ValueType newVT = Op.getValueType();
3271      MVT::ValueType oldVT = Op.getOperand(0).getValueType();
3272      if (TLI.getConvertAction(oldVT, newVT) == TargetLowering::Expand) {
3273        // The only way we can lower this is to turn it into a STORE,
3274        // LOAD pair, targetting a temporary location (a stack slot).
3275
3276        // NOTE: there is a choice here between constantly creating new stack
3277        // slots and always reusing the same one.  We currently always create
3278        // new ones, as reuse may inhibit scheduling.
3279        MVT::ValueType slotVT =
3280                (Node->getOpcode() == ISD::FP_EXTEND) ? oldVT : newVT;
3281        const Type *Ty = MVT::getTypeForValueType(slotVT);
3282        uint64_t TySize = TLI.getTargetData()->getTypeSize(Ty);
3283        unsigned Align  = TLI.getTargetData()->getPrefTypeAlignment(Ty);
3284        MachineFunction &MF = DAG.getMachineFunction();
3285        int SSFI =
3286          MF.getFrameInfo()->CreateStackObject(TySize, Align);
3287        SDOperand StackSlot = DAG.getFrameIndex(SSFI, TLI.getPointerTy());
3288        if (Node->getOpcode() == ISD::FP_EXTEND) {
3289          Result = DAG.getStore(DAG.getEntryNode(), Node->getOperand(0),
3290                                     StackSlot, NULL, 0);
3291          Result = DAG.getExtLoad(ISD::EXTLOAD, newVT,
3292                                     Result, StackSlot, NULL, 0, oldVT);
3293        } else {
3294          Result = DAG.getTruncStore(DAG.getEntryNode(), Node->getOperand(0),
3295                                     StackSlot, NULL, 0, newVT);
3296          Result = DAG.getLoad(newVT, Result, StackSlot, NULL, 0, newVT);
3297        }
3298        break;
3299      }
3300    }
3301    // FALL THROUGH
3302  case ISD::ANY_EXTEND:
3303  case ISD::ZERO_EXTEND:
3304  case ISD::SIGN_EXTEND:
3305    switch (getTypeAction(Node->getOperand(0).getValueType())) {
3306    case Expand: assert(0 && "Shouldn't need to expand other operators here!");
3307    case Legal:
3308      Tmp1 = LegalizeOp(Node->getOperand(0));
3309      Result = DAG.UpdateNodeOperands(Result, Tmp1);
3310      break;
3311    case Promote:
3312      switch (Node->getOpcode()) {
3313      case ISD::ANY_EXTEND:
3314        Tmp1 = PromoteOp(Node->getOperand(0));
3315        Result = DAG.getNode(ISD::ANY_EXTEND, Op.getValueType(), Tmp1);
3316        break;
3317      case ISD::ZERO_EXTEND:
3318        Result = PromoteOp(Node->getOperand(0));
3319        Result = DAG.getNode(ISD::ANY_EXTEND, Op.getValueType(), Result);
3320        Result = DAG.getZeroExtendInReg(Result,
3321                                        Node->getOperand(0).getValueType());
3322        break;
3323      case ISD::SIGN_EXTEND:
3324        Result = PromoteOp(Node->getOperand(0));
3325        Result = DAG.getNode(ISD::ANY_EXTEND, Op.getValueType(), Result);
3326        Result = DAG.getNode(ISD::SIGN_EXTEND_INREG, Result.getValueType(),
3327                             Result,
3328                          DAG.getValueType(Node->getOperand(0).getValueType()));
3329        break;
3330      case ISD::FP_EXTEND:
3331        Result = PromoteOp(Node->getOperand(0));
3332        if (Result.getValueType() != Op.getValueType())
3333          // Dynamically dead while we have only 2 FP types.
3334          Result = DAG.getNode(ISD::FP_EXTEND, Op.getValueType(), Result);
3335        break;
3336      case ISD::FP_ROUND:
3337        Result = PromoteOp(Node->getOperand(0));
3338        Result = DAG.getNode(Node->getOpcode(), Op.getValueType(), Result);
3339        break;
3340      }
3341    }
3342    break;
3343  case ISD::FP_ROUND_INREG:
3344  case ISD::SIGN_EXTEND_INREG: {
3345    Tmp1 = LegalizeOp(Node->getOperand(0));
3346    MVT::ValueType ExtraVT = cast<VTSDNode>(Node->getOperand(1))->getVT();
3347
3348    // If this operation is not supported, convert it to a shl/shr or load/store
3349    // pair.
3350    switch (TLI.getOperationAction(Node->getOpcode(), ExtraVT)) {
3351    default: assert(0 && "This action not supported for this op yet!");
3352    case TargetLowering::Legal:
3353      Result = DAG.UpdateNodeOperands(Result, Tmp1, Node->getOperand(1));
3354      break;
3355    case TargetLowering::Expand:
3356      // If this is an integer extend and shifts are supported, do that.
3357      if (Node->getOpcode() == ISD::SIGN_EXTEND_INREG) {
3358        // NOTE: we could fall back on load/store here too for targets without
3359        // SAR.  However, it is doubtful that any exist.
3360        unsigned BitsDiff = MVT::getSizeInBits(Node->getValueType(0)) -
3361                            MVT::getSizeInBits(ExtraVT);
3362        SDOperand ShiftCst = DAG.getConstant(BitsDiff, TLI.getShiftAmountTy());
3363        Result = DAG.getNode(ISD::SHL, Node->getValueType(0),
3364                             Node->getOperand(0), ShiftCst);
3365        Result = DAG.getNode(ISD::SRA, Node->getValueType(0),
3366                             Result, ShiftCst);
3367      } else if (Node->getOpcode() == ISD::FP_ROUND_INREG) {
3368        // The only way we can lower this is to turn it into a TRUNCSTORE,
3369        // EXTLOAD pair, targetting a temporary location (a stack slot).
3370
3371        // NOTE: there is a choice here between constantly creating new stack
3372        // slots and always reusing the same one.  We currently always create
3373        // new ones, as reuse may inhibit scheduling.
3374        const Type *Ty = MVT::getTypeForValueType(ExtraVT);
3375        uint64_t TySize = TLI.getTargetData()->getTypeSize(Ty);
3376        unsigned Align  = TLI.getTargetData()->getPrefTypeAlignment(Ty);
3377        MachineFunction &MF = DAG.getMachineFunction();
3378        int SSFI =
3379          MF.getFrameInfo()->CreateStackObject(TySize, Align);
3380        SDOperand StackSlot = DAG.getFrameIndex(SSFI, TLI.getPointerTy());
3381        Result = DAG.getTruncStore(DAG.getEntryNode(), Node->getOperand(0),
3382                                   StackSlot, NULL, 0, ExtraVT);
3383        Result = DAG.getExtLoad(ISD::EXTLOAD, Node->getValueType(0),
3384                                Result, StackSlot, NULL, 0, ExtraVT);
3385      } else {
3386        assert(0 && "Unknown op");
3387      }
3388      break;
3389    }
3390    break;
3391  }
3392  case ISD::TRAMPOLINE: {
3393    SDOperand Ops[6];
3394    for (unsigned i = 0; i != 6; ++i)
3395      Ops[i] = LegalizeOp(Node->getOperand(i));
3396    Result = DAG.UpdateNodeOperands(Result, Ops, 6);
3397    // The only option for this node is to custom lower it.
3398    Result = TLI.LowerOperation(Result, DAG);
3399    assert(Result.Val && "Should always custom lower!");
3400
3401    // Since trampoline produces two values, make sure to remember that we
3402    // legalized both of them.
3403    Tmp1 = LegalizeOp(Result.getValue(1));
3404    Result = LegalizeOp(Result);
3405    AddLegalizedOperand(SDOperand(Node, 0), Result);
3406    AddLegalizedOperand(SDOperand(Node, 1), Tmp1);
3407    return Op.ResNo ? Tmp1 : Result;
3408  }
3409  }
3410
3411  assert(Result.getValueType() == Op.getValueType() &&
3412         "Bad legalization!");
3413
3414  // Make sure that the generated code is itself legal.
3415  if (Result != Op)
3416    Result = LegalizeOp(Result);
3417
3418  // Note that LegalizeOp may be reentered even from single-use nodes, which
3419  // means that we always must cache transformed nodes.
3420  AddLegalizedOperand(Op, Result);
3421  return Result;
3422}
3423
3424/// PromoteOp - Given an operation that produces a value in an invalid type,
3425/// promote it to compute the value into a larger type.  The produced value will
3426/// have the correct bits for the low portion of the register, but no guarantee
3427/// is made about the top bits: it may be zero, sign-extended, or garbage.
3428SDOperand SelectionDAGLegalize::PromoteOp(SDOperand Op) {
3429  MVT::ValueType VT = Op.getValueType();
3430  MVT::ValueType NVT = TLI.getTypeToTransformTo(VT);
3431  assert(getTypeAction(VT) == Promote &&
3432         "Caller should expand or legalize operands that are not promotable!");
3433  assert(NVT > VT && MVT::isInteger(NVT) == MVT::isInteger(VT) &&
3434         "Cannot promote to smaller type!");
3435
3436  SDOperand Tmp1, Tmp2, Tmp3;
3437  SDOperand Result;
3438  SDNode *Node = Op.Val;
3439
3440  DenseMap<SDOperand, SDOperand>::iterator I = PromotedNodes.find(Op);
3441  if (I != PromotedNodes.end()) return I->second;
3442
3443  switch (Node->getOpcode()) {
3444  case ISD::CopyFromReg:
3445    assert(0 && "CopyFromReg must be legal!");
3446  default:
3447#ifndef NDEBUG
3448    cerr << "NODE: "; Node->dump(&DAG); cerr << "\n";
3449#endif
3450    assert(0 && "Do not know how to promote this operator!");
3451    abort();
3452  case ISD::UNDEF:
3453    Result = DAG.getNode(ISD::UNDEF, NVT);
3454    break;
3455  case ISD::Constant:
3456    if (VT != MVT::i1)
3457      Result = DAG.getNode(ISD::SIGN_EXTEND, NVT, Op);
3458    else
3459      Result = DAG.getNode(ISD::ZERO_EXTEND, NVT, Op);
3460    assert(isa<ConstantSDNode>(Result) && "Didn't constant fold zext?");
3461    break;
3462  case ISD::ConstantFP:
3463    Result = DAG.getNode(ISD::FP_EXTEND, NVT, Op);
3464    assert(isa<ConstantFPSDNode>(Result) && "Didn't constant fold fp_extend?");
3465    break;
3466
3467  case ISD::SETCC:
3468    assert(isTypeLegal(TLI.getSetCCResultTy()) && "SetCC type is not legal??");
3469    Result = DAG.getNode(ISD::SETCC, TLI.getSetCCResultTy(),Node->getOperand(0),
3470                         Node->getOperand(1), Node->getOperand(2));
3471    break;
3472
3473  case ISD::TRUNCATE:
3474    switch (getTypeAction(Node->getOperand(0).getValueType())) {
3475    case Legal:
3476      Result = LegalizeOp(Node->getOperand(0));
3477      assert(Result.getValueType() >= NVT &&
3478             "This truncation doesn't make sense!");
3479      if (Result.getValueType() > NVT)    // Truncate to NVT instead of VT
3480        Result = DAG.getNode(ISD::TRUNCATE, NVT, Result);
3481      break;
3482    case Promote:
3483      // The truncation is not required, because we don't guarantee anything
3484      // about high bits anyway.
3485      Result = PromoteOp(Node->getOperand(0));
3486      break;
3487    case Expand:
3488      ExpandOp(Node->getOperand(0), Tmp1, Tmp2);
3489      // Truncate the low part of the expanded value to the result type
3490      Result = DAG.getNode(ISD::TRUNCATE, NVT, Tmp1);
3491    }
3492    break;
3493  case ISD::SIGN_EXTEND:
3494  case ISD::ZERO_EXTEND:
3495  case ISD::ANY_EXTEND:
3496    switch (getTypeAction(Node->getOperand(0).getValueType())) {
3497    case Expand: assert(0 && "BUG: Smaller reg should have been promoted!");
3498    case Legal:
3499      // Input is legal?  Just do extend all the way to the larger type.
3500      Result = DAG.getNode(Node->getOpcode(), NVT, Node->getOperand(0));
3501      break;
3502    case Promote:
3503      // Promote the reg if it's smaller.
3504      Result = PromoteOp(Node->getOperand(0));
3505      // The high bits are not guaranteed to be anything.  Insert an extend.
3506      if (Node->getOpcode() == ISD::SIGN_EXTEND)
3507        Result = DAG.getNode(ISD::SIGN_EXTEND_INREG, NVT, Result,
3508                         DAG.getValueType(Node->getOperand(0).getValueType()));
3509      else if (Node->getOpcode() == ISD::ZERO_EXTEND)
3510        Result = DAG.getZeroExtendInReg(Result,
3511                                        Node->getOperand(0).getValueType());
3512      break;
3513    }
3514    break;
3515  case ISD::BIT_CONVERT:
3516    Result = ExpandBIT_CONVERT(Node->getValueType(0), Node->getOperand(0));
3517    Result = PromoteOp(Result);
3518    break;
3519
3520  case ISD::FP_EXTEND:
3521    assert(0 && "Case not implemented.  Dynamically dead with 2 FP types!");
3522  case ISD::FP_ROUND:
3523    switch (getTypeAction(Node->getOperand(0).getValueType())) {
3524    case Expand: assert(0 && "BUG: Cannot expand FP regs!");
3525    case Promote:  assert(0 && "Unreachable with 2 FP types!");
3526    case Legal:
3527      // Input is legal?  Do an FP_ROUND_INREG.
3528      Result = DAG.getNode(ISD::FP_ROUND_INREG, NVT, Node->getOperand(0),
3529                           DAG.getValueType(VT));
3530      break;
3531    }
3532    break;
3533
3534  case ISD::SINT_TO_FP:
3535  case ISD::UINT_TO_FP:
3536    switch (getTypeAction(Node->getOperand(0).getValueType())) {
3537    case Legal:
3538      // No extra round required here.
3539      Result = DAG.getNode(Node->getOpcode(), NVT, Node->getOperand(0));
3540      break;
3541
3542    case Promote:
3543      Result = PromoteOp(Node->getOperand(0));
3544      if (Node->getOpcode() == ISD::SINT_TO_FP)
3545        Result = DAG.getNode(ISD::SIGN_EXTEND_INREG, Result.getValueType(),
3546                             Result,
3547                         DAG.getValueType(Node->getOperand(0).getValueType()));
3548      else
3549        Result = DAG.getZeroExtendInReg(Result,
3550                                        Node->getOperand(0).getValueType());
3551      // No extra round required here.
3552      Result = DAG.getNode(Node->getOpcode(), NVT, Result);
3553      break;
3554    case Expand:
3555      Result = ExpandIntToFP(Node->getOpcode() == ISD::SINT_TO_FP, NVT,
3556                             Node->getOperand(0));
3557      // Round if we cannot tolerate excess precision.
3558      if (NoExcessFPPrecision)
3559        Result = DAG.getNode(ISD::FP_ROUND_INREG, NVT, Result,
3560                             DAG.getValueType(VT));
3561      break;
3562    }
3563    break;
3564
3565  case ISD::SIGN_EXTEND_INREG:
3566    Result = PromoteOp(Node->getOperand(0));
3567    Result = DAG.getNode(ISD::SIGN_EXTEND_INREG, NVT, Result,
3568                         Node->getOperand(1));
3569    break;
3570  case ISD::FP_TO_SINT:
3571  case ISD::FP_TO_UINT:
3572    switch (getTypeAction(Node->getOperand(0).getValueType())) {
3573    case Legal:
3574    case Expand:
3575      Tmp1 = Node->getOperand(0);
3576      break;
3577    case Promote:
3578      // The input result is prerounded, so we don't have to do anything
3579      // special.
3580      Tmp1 = PromoteOp(Node->getOperand(0));
3581      break;
3582    }
3583    // If we're promoting a UINT to a larger size, check to see if the new node
3584    // will be legal.  If it isn't, check to see if FP_TO_SINT is legal, since
3585    // we can use that instead.  This allows us to generate better code for
3586    // FP_TO_UINT for small destination sizes on targets where FP_TO_UINT is not
3587    // legal, such as PowerPC.
3588    if (Node->getOpcode() == ISD::FP_TO_UINT &&
3589        !TLI.isOperationLegal(ISD::FP_TO_UINT, NVT) &&
3590        (TLI.isOperationLegal(ISD::FP_TO_SINT, NVT) ||
3591         TLI.getOperationAction(ISD::FP_TO_SINT, NVT)==TargetLowering::Custom)){
3592      Result = DAG.getNode(ISD::FP_TO_SINT, NVT, Tmp1);
3593    } else {
3594      Result = DAG.getNode(Node->getOpcode(), NVT, Tmp1);
3595    }
3596    break;
3597
3598  case ISD::FABS:
3599  case ISD::FNEG:
3600    Tmp1 = PromoteOp(Node->getOperand(0));
3601    assert(Tmp1.getValueType() == NVT);
3602    Result = DAG.getNode(Node->getOpcode(), NVT, Tmp1);
3603    // NOTE: we do not have to do any extra rounding here for
3604    // NoExcessFPPrecision, because we know the input will have the appropriate
3605    // precision, and these operations don't modify precision at all.
3606    break;
3607
3608  case ISD::FSQRT:
3609  case ISD::FSIN:
3610  case ISD::FCOS:
3611    Tmp1 = PromoteOp(Node->getOperand(0));
3612    assert(Tmp1.getValueType() == NVT);
3613    Result = DAG.getNode(Node->getOpcode(), NVT, Tmp1);
3614    if (NoExcessFPPrecision)
3615      Result = DAG.getNode(ISD::FP_ROUND_INREG, NVT, Result,
3616                           DAG.getValueType(VT));
3617    break;
3618
3619  case ISD::FPOWI: {
3620    // Promote f32 powi to f64 powi.  Note that this could insert a libcall
3621    // directly as well, which may be better.
3622    Tmp1 = PromoteOp(Node->getOperand(0));
3623    assert(Tmp1.getValueType() == NVT);
3624    Result = DAG.getNode(ISD::FPOWI, NVT, Tmp1, Node->getOperand(1));
3625    if (NoExcessFPPrecision)
3626      Result = DAG.getNode(ISD::FP_ROUND_INREG, NVT, Result,
3627                           DAG.getValueType(VT));
3628    break;
3629  }
3630
3631  case ISD::AND:
3632  case ISD::OR:
3633  case ISD::XOR:
3634  case ISD::ADD:
3635  case ISD::SUB:
3636  case ISD::MUL:
3637    // The input may have strange things in the top bits of the registers, but
3638    // these operations don't care.  They may have weird bits going out, but
3639    // that too is okay if they are integer operations.
3640    Tmp1 = PromoteOp(Node->getOperand(0));
3641    Tmp2 = PromoteOp(Node->getOperand(1));
3642    assert(Tmp1.getValueType() == NVT && Tmp2.getValueType() == NVT);
3643    Result = DAG.getNode(Node->getOpcode(), NVT, Tmp1, Tmp2);
3644    break;
3645  case ISD::FADD:
3646  case ISD::FSUB:
3647  case ISD::FMUL:
3648    Tmp1 = PromoteOp(Node->getOperand(0));
3649    Tmp2 = PromoteOp(Node->getOperand(1));
3650    assert(Tmp1.getValueType() == NVT && Tmp2.getValueType() == NVT);
3651    Result = DAG.getNode(Node->getOpcode(), NVT, Tmp1, Tmp2);
3652
3653    // Floating point operations will give excess precision that we may not be
3654    // able to tolerate.  If we DO allow excess precision, just leave it,
3655    // otherwise excise it.
3656    // FIXME: Why would we need to round FP ops more than integer ones?
3657    //     Is Round(Add(Add(A,B),C)) != Round(Add(Round(Add(A,B)), C))
3658    if (NoExcessFPPrecision)
3659      Result = DAG.getNode(ISD::FP_ROUND_INREG, NVT, Result,
3660                           DAG.getValueType(VT));
3661    break;
3662
3663  case ISD::SDIV:
3664  case ISD::SREM:
3665    // These operators require that their input be sign extended.
3666    Tmp1 = PromoteOp(Node->getOperand(0));
3667    Tmp2 = PromoteOp(Node->getOperand(1));
3668    if (MVT::isInteger(NVT)) {
3669      Tmp1 = DAG.getNode(ISD::SIGN_EXTEND_INREG, NVT, Tmp1,
3670                         DAG.getValueType(VT));
3671      Tmp2 = DAG.getNode(ISD::SIGN_EXTEND_INREG, NVT, Tmp2,
3672                         DAG.getValueType(VT));
3673    }
3674    Result = DAG.getNode(Node->getOpcode(), NVT, Tmp1, Tmp2);
3675
3676    // Perform FP_ROUND: this is probably overly pessimistic.
3677    if (MVT::isFloatingPoint(NVT) && NoExcessFPPrecision)
3678      Result = DAG.getNode(ISD::FP_ROUND_INREG, NVT, Result,
3679                           DAG.getValueType(VT));
3680    break;
3681  case ISD::FDIV:
3682  case ISD::FREM:
3683  case ISD::FCOPYSIGN:
3684    // These operators require that their input be fp extended.
3685    switch (getTypeAction(Node->getOperand(0).getValueType())) {
3686      case Legal:
3687        Tmp1 = LegalizeOp(Node->getOperand(0));
3688        break;
3689      case Promote:
3690        Tmp1 = PromoteOp(Node->getOperand(0));
3691        break;
3692      case Expand:
3693        assert(0 && "not implemented");
3694    }
3695    switch (getTypeAction(Node->getOperand(1).getValueType())) {
3696      case Legal:
3697        Tmp2 = LegalizeOp(Node->getOperand(1));
3698        break;
3699      case Promote:
3700        Tmp2 = PromoteOp(Node->getOperand(1));
3701        break;
3702      case Expand:
3703        assert(0 && "not implemented");
3704    }
3705    Result = DAG.getNode(Node->getOpcode(), NVT, Tmp1, Tmp2);
3706
3707    // Perform FP_ROUND: this is probably overly pessimistic.
3708    if (NoExcessFPPrecision && Node->getOpcode() != ISD::FCOPYSIGN)
3709      Result = DAG.getNode(ISD::FP_ROUND_INREG, NVT, Result,
3710                           DAG.getValueType(VT));
3711    break;
3712
3713  case ISD::UDIV:
3714  case ISD::UREM:
3715    // These operators require that their input be zero extended.
3716    Tmp1 = PromoteOp(Node->getOperand(0));
3717    Tmp2 = PromoteOp(Node->getOperand(1));
3718    assert(MVT::isInteger(NVT) && "Operators don't apply to FP!");
3719    Tmp1 = DAG.getZeroExtendInReg(Tmp1, VT);
3720    Tmp2 = DAG.getZeroExtendInReg(Tmp2, VT);
3721    Result = DAG.getNode(Node->getOpcode(), NVT, Tmp1, Tmp2);
3722    break;
3723
3724  case ISD::SHL:
3725    Tmp1 = PromoteOp(Node->getOperand(0));
3726    Result = DAG.getNode(ISD::SHL, NVT, Tmp1, Node->getOperand(1));
3727    break;
3728  case ISD::SRA:
3729    // The input value must be properly sign extended.
3730    Tmp1 = PromoteOp(Node->getOperand(0));
3731    Tmp1 = DAG.getNode(ISD::SIGN_EXTEND_INREG, NVT, Tmp1,
3732                       DAG.getValueType(VT));
3733    Result = DAG.getNode(ISD::SRA, NVT, Tmp1, Node->getOperand(1));
3734    break;
3735  case ISD::SRL:
3736    // The input value must be properly zero extended.
3737    Tmp1 = PromoteOp(Node->getOperand(0));
3738    Tmp1 = DAG.getZeroExtendInReg(Tmp1, VT);
3739    Result = DAG.getNode(ISD::SRL, NVT, Tmp1, Node->getOperand(1));
3740    break;
3741
3742  case ISD::VAARG:
3743    Tmp1 = Node->getOperand(0);   // Get the chain.
3744    Tmp2 = Node->getOperand(1);   // Get the pointer.
3745    if (TLI.getOperationAction(ISD::VAARG, VT) == TargetLowering::Custom) {
3746      Tmp3 = DAG.getVAArg(VT, Tmp1, Tmp2, Node->getOperand(2));
3747      Result = TLI.CustomPromoteOperation(Tmp3, DAG);
3748    } else {
3749      SrcValueSDNode *SV = cast<SrcValueSDNode>(Node->getOperand(2));
3750      SDOperand VAList = DAG.getLoad(TLI.getPointerTy(), Tmp1, Tmp2,
3751                                     SV->getValue(), SV->getOffset());
3752      // Increment the pointer, VAList, to the next vaarg
3753      Tmp3 = DAG.getNode(ISD::ADD, TLI.getPointerTy(), VAList,
3754                         DAG.getConstant(MVT::getSizeInBits(VT)/8,
3755                                         TLI.getPointerTy()));
3756      // Store the incremented VAList to the legalized pointer
3757      Tmp3 = DAG.getStore(VAList.getValue(1), Tmp3, Tmp2, SV->getValue(),
3758                          SV->getOffset());
3759      // Load the actual argument out of the pointer VAList
3760      Result = DAG.getExtLoad(ISD::EXTLOAD, NVT, Tmp3, VAList, NULL, 0, VT);
3761    }
3762    // Remember that we legalized the chain.
3763    AddLegalizedOperand(Op.getValue(1), LegalizeOp(Result.getValue(1)));
3764    break;
3765
3766  case ISD::LOAD: {
3767    LoadSDNode *LD = cast<LoadSDNode>(Node);
3768    ISD::LoadExtType ExtType = ISD::isNON_EXTLoad(Node)
3769      ? ISD::EXTLOAD : LD->getExtensionType();
3770    Result = DAG.getExtLoad(ExtType, NVT,
3771                            LD->getChain(), LD->getBasePtr(),
3772                            LD->getSrcValue(), LD->getSrcValueOffset(),
3773                            LD->getLoadedVT(),
3774                            LD->isVolatile(),
3775                            LD->getAlignment());
3776    // Remember that we legalized the chain.
3777    AddLegalizedOperand(Op.getValue(1), LegalizeOp(Result.getValue(1)));
3778    break;
3779  }
3780  case ISD::SELECT:
3781    Tmp2 = PromoteOp(Node->getOperand(1));   // Legalize the op0
3782    Tmp3 = PromoteOp(Node->getOperand(2));   // Legalize the op1
3783    Result = DAG.getNode(ISD::SELECT, NVT, Node->getOperand(0), Tmp2, Tmp3);
3784    break;
3785  case ISD::SELECT_CC:
3786    Tmp2 = PromoteOp(Node->getOperand(2));   // True
3787    Tmp3 = PromoteOp(Node->getOperand(3));   // False
3788    Result = DAG.getNode(ISD::SELECT_CC, NVT, Node->getOperand(0),
3789                         Node->getOperand(1), Tmp2, Tmp3, Node->getOperand(4));
3790    break;
3791  case ISD::BSWAP:
3792    Tmp1 = Node->getOperand(0);
3793    Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, NVT, Tmp1);
3794    Tmp1 = DAG.getNode(ISD::BSWAP, NVT, Tmp1);
3795    Result = DAG.getNode(ISD::SRL, NVT, Tmp1,
3796                         DAG.getConstant(MVT::getSizeInBits(NVT) -
3797                                         MVT::getSizeInBits(VT),
3798                                         TLI.getShiftAmountTy()));
3799    break;
3800  case ISD::CTPOP:
3801  case ISD::CTTZ:
3802  case ISD::CTLZ:
3803    // Zero extend the argument
3804    Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, NVT, Node->getOperand(0));
3805    // Perform the larger operation, then subtract if needed.
3806    Tmp1 = DAG.getNode(Node->getOpcode(), NVT, Tmp1);
3807    switch(Node->getOpcode()) {
3808    case ISD::CTPOP:
3809      Result = Tmp1;
3810      break;
3811    case ISD::CTTZ:
3812      // if Tmp1 == sizeinbits(NVT) then Tmp1 = sizeinbits(Old VT)
3813      Tmp2 = DAG.getSetCC(TLI.getSetCCResultTy(), Tmp1,
3814                          DAG.getConstant(MVT::getSizeInBits(NVT), NVT),
3815                          ISD::SETEQ);
3816      Result = DAG.getNode(ISD::SELECT, NVT, Tmp2,
3817                           DAG.getConstant(MVT::getSizeInBits(VT), NVT), Tmp1);
3818      break;
3819    case ISD::CTLZ:
3820      //Tmp1 = Tmp1 - (sizeinbits(NVT) - sizeinbits(Old VT))
3821      Result = DAG.getNode(ISD::SUB, NVT, Tmp1,
3822                           DAG.getConstant(MVT::getSizeInBits(NVT) -
3823                                           MVT::getSizeInBits(VT), NVT));
3824      break;
3825    }
3826    break;
3827  case ISD::EXTRACT_SUBVECTOR:
3828    Result = PromoteOp(ExpandEXTRACT_SUBVECTOR(Op));
3829    break;
3830  case ISD::EXTRACT_VECTOR_ELT:
3831    Result = PromoteOp(ExpandEXTRACT_VECTOR_ELT(Op));
3832    break;
3833  }
3834
3835  assert(Result.Val && "Didn't set a result!");
3836
3837  // Make sure the result is itself legal.
3838  Result = LegalizeOp(Result);
3839
3840  // Remember that we promoted this!
3841  AddPromotedOperand(Op, Result);
3842  return Result;
3843}
3844
3845/// ExpandEXTRACT_VECTOR_ELT - Expand an EXTRACT_VECTOR_ELT operation into
3846/// a legal EXTRACT_VECTOR_ELT operation, scalar code, or memory traffic,
3847/// based on the vector type. The return type of this matches the element type
3848/// of the vector, which may not be legal for the target.
3849SDOperand SelectionDAGLegalize::ExpandEXTRACT_VECTOR_ELT(SDOperand Op) {
3850  // We know that operand #0 is the Vec vector.  If the index is a constant
3851  // or if the invec is a supported hardware type, we can use it.  Otherwise,
3852  // lower to a store then an indexed load.
3853  SDOperand Vec = Op.getOperand(0);
3854  SDOperand Idx = Op.getOperand(1);
3855
3856  SDNode *InVal = Vec.Val;
3857  MVT::ValueType TVT = InVal->getValueType(0);
3858  unsigned NumElems = MVT::getVectorNumElements(TVT);
3859
3860  switch (TLI.getOperationAction(ISD::EXTRACT_VECTOR_ELT, TVT)) {
3861  default: assert(0 && "This action is not supported yet!");
3862  case TargetLowering::Custom: {
3863    Vec = LegalizeOp(Vec);
3864    Op = DAG.UpdateNodeOperands(Op, Vec, Idx);
3865    SDOperand Tmp3 = TLI.LowerOperation(Op, DAG);
3866    if (Tmp3.Val)
3867      return Tmp3;
3868    break;
3869  }
3870  case TargetLowering::Legal:
3871    if (isTypeLegal(TVT)) {
3872      Vec = LegalizeOp(Vec);
3873      Op = DAG.UpdateNodeOperands(Op, Vec, Idx);
3874      return Op;
3875    }
3876    break;
3877  case TargetLowering::Expand:
3878    break;
3879  }
3880
3881  if (NumElems == 1) {
3882    // This must be an access of the only element.  Return it.
3883    Op = ScalarizeVectorOp(Vec);
3884  } else if (!TLI.isTypeLegal(TVT) && isa<ConstantSDNode>(Idx)) {
3885    ConstantSDNode *CIdx = cast<ConstantSDNode>(Idx);
3886    SDOperand Lo, Hi;
3887    SplitVectorOp(Vec, Lo, Hi);
3888    if (CIdx->getValue() < NumElems/2) {
3889      Vec = Lo;
3890    } else {
3891      Vec = Hi;
3892      Idx = DAG.getConstant(CIdx->getValue() - NumElems/2,
3893                            Idx.getValueType());
3894    }
3895
3896    // It's now an extract from the appropriate high or low part.  Recurse.
3897    Op = DAG.UpdateNodeOperands(Op, Vec, Idx);
3898    Op = ExpandEXTRACT_VECTOR_ELT(Op);
3899  } else {
3900    // Store the value to a temporary stack slot, then LOAD the scalar
3901    // element back out.
3902    SDOperand StackPtr = CreateStackTemporary(Vec.getValueType());
3903    SDOperand Ch = DAG.getStore(DAG.getEntryNode(), Vec, StackPtr, NULL, 0);
3904
3905    // Add the offset to the index.
3906    unsigned EltSize = MVT::getSizeInBits(Op.getValueType())/8;
3907    Idx = DAG.getNode(ISD::MUL, Idx.getValueType(), Idx,
3908                      DAG.getConstant(EltSize, Idx.getValueType()));
3909    StackPtr = DAG.getNode(ISD::ADD, Idx.getValueType(), Idx, StackPtr);
3910
3911    Op = DAG.getLoad(Op.getValueType(), Ch, StackPtr, NULL, 0);
3912  }
3913  return Op;
3914}
3915
3916/// ExpandEXTRACT_SUBVECTOR - Expand a EXTRACT_SUBVECTOR operation.  For now
3917/// we assume the operation can be split if it is not already legal.
3918SDOperand SelectionDAGLegalize::ExpandEXTRACT_SUBVECTOR(SDOperand Op) {
3919  // We know that operand #0 is the Vec vector.  For now we assume the index
3920  // is a constant and that the extracted result is a supported hardware type.
3921  SDOperand Vec = Op.getOperand(0);
3922  SDOperand Idx = LegalizeOp(Op.getOperand(1));
3923
3924  unsigned NumElems = MVT::getVectorNumElements(Vec.getValueType());
3925
3926  if (NumElems == MVT::getVectorNumElements(Op.getValueType())) {
3927    // This must be an access of the desired vector length.  Return it.
3928    return Vec;
3929  }
3930
3931  ConstantSDNode *CIdx = cast<ConstantSDNode>(Idx);
3932  SDOperand Lo, Hi;
3933  SplitVectorOp(Vec, Lo, Hi);
3934  if (CIdx->getValue() < NumElems/2) {
3935    Vec = Lo;
3936  } else {
3937    Vec = Hi;
3938    Idx = DAG.getConstant(CIdx->getValue() - NumElems/2, Idx.getValueType());
3939  }
3940
3941  // It's now an extract from the appropriate high or low part.  Recurse.
3942  Op = DAG.UpdateNodeOperands(Op, Vec, Idx);
3943  return ExpandEXTRACT_SUBVECTOR(Op);
3944}
3945
3946/// LegalizeSetCCOperands - Attempts to create a legal LHS and RHS for a SETCC
3947/// with condition CC on the current target.  This usually involves legalizing
3948/// or promoting the arguments.  In the case where LHS and RHS must be expanded,
3949/// there may be no choice but to create a new SetCC node to represent the
3950/// legalized value of setcc lhs, rhs.  In this case, the value is returned in
3951/// LHS, and the SDOperand returned in RHS has a nil SDNode value.
3952void SelectionDAGLegalize::LegalizeSetCCOperands(SDOperand &LHS,
3953                                                 SDOperand &RHS,
3954                                                 SDOperand &CC) {
3955  SDOperand Tmp1, Tmp2, Result;
3956
3957  switch (getTypeAction(LHS.getValueType())) {
3958  case Legal:
3959    Tmp1 = LegalizeOp(LHS);   // LHS
3960    Tmp2 = LegalizeOp(RHS);   // RHS
3961    break;
3962  case Promote:
3963    Tmp1 = PromoteOp(LHS);   // LHS
3964    Tmp2 = PromoteOp(RHS);   // RHS
3965
3966    // If this is an FP compare, the operands have already been extended.
3967    if (MVT::isInteger(LHS.getValueType())) {
3968      MVT::ValueType VT = LHS.getValueType();
3969      MVT::ValueType NVT = TLI.getTypeToTransformTo(VT);
3970
3971      // Otherwise, we have to insert explicit sign or zero extends.  Note
3972      // that we could insert sign extends for ALL conditions, but zero extend
3973      // is cheaper on many machines (an AND instead of two shifts), so prefer
3974      // it.
3975      switch (cast<CondCodeSDNode>(CC)->get()) {
3976      default: assert(0 && "Unknown integer comparison!");
3977      case ISD::SETEQ:
3978      case ISD::SETNE:
3979      case ISD::SETUGE:
3980      case ISD::SETUGT:
3981      case ISD::SETULE:
3982      case ISD::SETULT:
3983        // ALL of these operations will work if we either sign or zero extend
3984        // the operands (including the unsigned comparisons!).  Zero extend is
3985        // usually a simpler/cheaper operation, so prefer it.
3986        Tmp1 = DAG.getZeroExtendInReg(Tmp1, VT);
3987        Tmp2 = DAG.getZeroExtendInReg(Tmp2, VT);
3988        break;
3989      case ISD::SETGE:
3990      case ISD::SETGT:
3991      case ISD::SETLT:
3992      case ISD::SETLE:
3993        Tmp1 = DAG.getNode(ISD::SIGN_EXTEND_INREG, NVT, Tmp1,
3994                           DAG.getValueType(VT));
3995        Tmp2 = DAG.getNode(ISD::SIGN_EXTEND_INREG, NVT, Tmp2,
3996                           DAG.getValueType(VT));
3997        break;
3998      }
3999    }
4000    break;
4001  case Expand: {
4002    MVT::ValueType VT = LHS.getValueType();
4003    if (VT == MVT::f32 || VT == MVT::f64) {
4004      // Expand into one or more soft-fp libcall(s).
4005      RTLIB::Libcall LC1, LC2 = RTLIB::UNKNOWN_LIBCALL;
4006      switch (cast<CondCodeSDNode>(CC)->get()) {
4007      case ISD::SETEQ:
4008      case ISD::SETOEQ:
4009        LC1 = (VT == MVT::f32) ? RTLIB::OEQ_F32 : RTLIB::OEQ_F64;
4010        break;
4011      case ISD::SETNE:
4012      case ISD::SETUNE:
4013        LC1 = (VT == MVT::f32) ? RTLIB::UNE_F32 : RTLIB::UNE_F64;
4014        break;
4015      case ISD::SETGE:
4016      case ISD::SETOGE:
4017        LC1 = (VT == MVT::f32) ? RTLIB::OGE_F32 : RTLIB::OGE_F64;
4018        break;
4019      case ISD::SETLT:
4020      case ISD::SETOLT:
4021        LC1 = (VT == MVT::f32) ? RTLIB::OLT_F32 : RTLIB::OLT_F64;
4022        break;
4023      case ISD::SETLE:
4024      case ISD::SETOLE:
4025        LC1 = (VT == MVT::f32) ? RTLIB::OLE_F32 : RTLIB::OLE_F64;
4026        break;
4027      case ISD::SETGT:
4028      case ISD::SETOGT:
4029        LC1 = (VT == MVT::f32) ? RTLIB::OGT_F32 : RTLIB::OGT_F64;
4030        break;
4031      case ISD::SETUO:
4032        LC1 = (VT == MVT::f32) ? RTLIB::UO_F32 : RTLIB::UO_F64;
4033        break;
4034      case ISD::SETO:
4035        LC1 = (VT == MVT::f32) ? RTLIB::O_F32 : RTLIB::O_F64;
4036        break;
4037      default:
4038        LC1 = (VT == MVT::f32) ? RTLIB::UO_F32 : RTLIB::UO_F64;
4039        switch (cast<CondCodeSDNode>(CC)->get()) {
4040        case ISD::SETONE:
4041          // SETONE = SETOLT | SETOGT
4042          LC1 = (VT == MVT::f32) ? RTLIB::OLT_F32 : RTLIB::OLT_F64;
4043          // Fallthrough
4044        case ISD::SETUGT:
4045          LC2 = (VT == MVT::f32) ? RTLIB::OGT_F32 : RTLIB::OGT_F64;
4046          break;
4047        case ISD::SETUGE:
4048          LC2 = (VT == MVT::f32) ? RTLIB::OGE_F32 : RTLIB::OGE_F64;
4049          break;
4050        case ISD::SETULT:
4051          LC2 = (VT == MVT::f32) ? RTLIB::OLT_F32 : RTLIB::OLT_F64;
4052          break;
4053        case ISD::SETULE:
4054          LC2 = (VT == MVT::f32) ? RTLIB::OLE_F32 : RTLIB::OLE_F64;
4055          break;
4056        case ISD::SETUEQ:
4057          LC2 = (VT == MVT::f32) ? RTLIB::OEQ_F32 : RTLIB::OEQ_F64;
4058          break;
4059        default: assert(0 && "Unsupported FP setcc!");
4060        }
4061      }
4062
4063      SDOperand Dummy;
4064      Tmp1 = ExpandLibCall(TLI.getLibcallName(LC1),
4065                           DAG.getNode(ISD::MERGE_VALUES, VT, LHS, RHS).Val,
4066                           false /*sign irrelevant*/, Dummy);
4067      Tmp2 = DAG.getConstant(0, MVT::i32);
4068      CC = DAG.getCondCode(TLI.getCmpLibcallCC(LC1));
4069      if (LC2 != RTLIB::UNKNOWN_LIBCALL) {
4070        Tmp1 = DAG.getNode(ISD::SETCC, TLI.getSetCCResultTy(), Tmp1, Tmp2, CC);
4071        LHS = ExpandLibCall(TLI.getLibcallName(LC2),
4072                            DAG.getNode(ISD::MERGE_VALUES, VT, LHS, RHS).Val,
4073                            false /*sign irrelevant*/, Dummy);
4074        Tmp2 = DAG.getNode(ISD::SETCC, TLI.getSetCCResultTy(), LHS, Tmp2,
4075                           DAG.getCondCode(TLI.getCmpLibcallCC(LC2)));
4076        Tmp1 = DAG.getNode(ISD::OR, Tmp1.getValueType(), Tmp1, Tmp2);
4077        Tmp2 = SDOperand();
4078      }
4079      LHS = Tmp1;
4080      RHS = Tmp2;
4081      return;
4082    }
4083
4084    SDOperand LHSLo, LHSHi, RHSLo, RHSHi;
4085    ExpandOp(LHS, LHSLo, LHSHi);
4086    ExpandOp(RHS, RHSLo, RHSHi);
4087    switch (cast<CondCodeSDNode>(CC)->get()) {
4088    case ISD::SETEQ:
4089    case ISD::SETNE:
4090      if (RHSLo == RHSHi)
4091        if (ConstantSDNode *RHSCST = dyn_cast<ConstantSDNode>(RHSLo))
4092          if (RHSCST->isAllOnesValue()) {
4093            // Comparison to -1.
4094            Tmp1 = DAG.getNode(ISD::AND, LHSLo.getValueType(), LHSLo, LHSHi);
4095            Tmp2 = RHSLo;
4096            break;
4097          }
4098
4099      Tmp1 = DAG.getNode(ISD::XOR, LHSLo.getValueType(), LHSLo, RHSLo);
4100      Tmp2 = DAG.getNode(ISD::XOR, LHSLo.getValueType(), LHSHi, RHSHi);
4101      Tmp1 = DAG.getNode(ISD::OR, Tmp1.getValueType(), Tmp1, Tmp2);
4102      Tmp2 = DAG.getConstant(0, Tmp1.getValueType());
4103      break;
4104    default:
4105      // If this is a comparison of the sign bit, just look at the top part.
4106      // X > -1,  x < 0
4107      if (ConstantSDNode *CST = dyn_cast<ConstantSDNode>(RHS))
4108        if ((cast<CondCodeSDNode>(CC)->get() == ISD::SETLT &&
4109             CST->getValue() == 0) ||             // X < 0
4110            (cast<CondCodeSDNode>(CC)->get() == ISD::SETGT &&
4111             CST->isAllOnesValue())) {            // X > -1
4112          Tmp1 = LHSHi;
4113          Tmp2 = RHSHi;
4114          break;
4115        }
4116
4117      // FIXME: This generated code sucks.
4118      ISD::CondCode LowCC;
4119      ISD::CondCode CCCode = cast<CondCodeSDNode>(CC)->get();
4120      switch (CCCode) {
4121      default: assert(0 && "Unknown integer setcc!");
4122      case ISD::SETLT:
4123      case ISD::SETULT: LowCC = ISD::SETULT; break;
4124      case ISD::SETGT:
4125      case ISD::SETUGT: LowCC = ISD::SETUGT; break;
4126      case ISD::SETLE:
4127      case ISD::SETULE: LowCC = ISD::SETULE; break;
4128      case ISD::SETGE:
4129      case ISD::SETUGE: LowCC = ISD::SETUGE; break;
4130      }
4131
4132      // Tmp1 = lo(op1) < lo(op2)   // Always unsigned comparison
4133      // Tmp2 = hi(op1) < hi(op2)   // Signedness depends on operands
4134      // dest = hi(op1) == hi(op2) ? Tmp1 : Tmp2;
4135
4136      // NOTE: on targets without efficient SELECT of bools, we can always use
4137      // this identity: (B1 ? B2 : B3) --> (B1 & B2)|(!B1&B3)
4138      TargetLowering::DAGCombinerInfo DagCombineInfo(DAG, false, true, NULL);
4139      Tmp1 = TLI.SimplifySetCC(TLI.getSetCCResultTy(), LHSLo, RHSLo, LowCC,
4140                               false, DagCombineInfo);
4141      if (!Tmp1.Val)
4142        Tmp1 = DAG.getSetCC(TLI.getSetCCResultTy(), LHSLo, RHSLo, LowCC);
4143      Tmp2 = TLI.SimplifySetCC(TLI.getSetCCResultTy(), LHSHi, RHSHi,
4144                               CCCode, false, DagCombineInfo);
4145      if (!Tmp2.Val)
4146        Tmp2 = DAG.getNode(ISD::SETCC, TLI.getSetCCResultTy(), LHSHi, RHSHi, CC);
4147
4148      ConstantSDNode *Tmp1C = dyn_cast<ConstantSDNode>(Tmp1.Val);
4149      ConstantSDNode *Tmp2C = dyn_cast<ConstantSDNode>(Tmp2.Val);
4150      if ((Tmp1C && Tmp1C->getValue() == 0) ||
4151          (Tmp2C && Tmp2C->getValue() == 0 &&
4152           (CCCode == ISD::SETLE || CCCode == ISD::SETGE ||
4153            CCCode == ISD::SETUGE || CCCode == ISD::SETULE)) ||
4154          (Tmp2C && Tmp2C->getValue() == 1 &&
4155           (CCCode == ISD::SETLT || CCCode == ISD::SETGT ||
4156            CCCode == ISD::SETUGT || CCCode == ISD::SETULT))) {
4157        // low part is known false, returns high part.
4158        // For LE / GE, if high part is known false, ignore the low part.
4159        // For LT / GT, if high part is known true, ignore the low part.
4160        Tmp1 = Tmp2;
4161        Tmp2 = SDOperand();
4162      } else {
4163        Result = TLI.SimplifySetCC(TLI.getSetCCResultTy(), LHSHi, RHSHi,
4164                                   ISD::SETEQ, false, DagCombineInfo);
4165        if (!Result.Val)
4166          Result=DAG.getSetCC(TLI.getSetCCResultTy(), LHSHi, RHSHi, ISD::SETEQ);
4167        Result = LegalizeOp(DAG.getNode(ISD::SELECT, Tmp1.getValueType(),
4168                                        Result, Tmp1, Tmp2));
4169        Tmp1 = Result;
4170        Tmp2 = SDOperand();
4171      }
4172    }
4173  }
4174  }
4175  LHS = Tmp1;
4176  RHS = Tmp2;
4177}
4178
4179/// ExpandBIT_CONVERT - Expand a BIT_CONVERT node into a store/load combination.
4180/// The resultant code need not be legal.  Note that SrcOp is the input operand
4181/// to the BIT_CONVERT, not the BIT_CONVERT node itself.
4182SDOperand SelectionDAGLegalize::ExpandBIT_CONVERT(MVT::ValueType DestVT,
4183                                                  SDOperand SrcOp) {
4184  // Create the stack frame object.
4185  SDOperand FIPtr = CreateStackTemporary(DestVT);
4186
4187  // Emit a store to the stack slot.
4188  SDOperand Store = DAG.getStore(DAG.getEntryNode(), SrcOp, FIPtr, NULL, 0);
4189  // Result is a load from the stack slot.
4190  return DAG.getLoad(DestVT, Store, FIPtr, NULL, 0);
4191}
4192
4193SDOperand SelectionDAGLegalize::ExpandSCALAR_TO_VECTOR(SDNode *Node) {
4194  // Create a vector sized/aligned stack slot, store the value to element #0,
4195  // then load the whole vector back out.
4196  SDOperand StackPtr = CreateStackTemporary(Node->getValueType(0));
4197  SDOperand Ch = DAG.getStore(DAG.getEntryNode(), Node->getOperand(0), StackPtr,
4198                              NULL, 0);
4199  return DAG.getLoad(Node->getValueType(0), Ch, StackPtr, NULL, 0);
4200}
4201
4202
4203/// ExpandBUILD_VECTOR - Expand a BUILD_VECTOR node on targets that don't
4204/// support the operation, but do support the resultant vector type.
4205SDOperand SelectionDAGLegalize::ExpandBUILD_VECTOR(SDNode *Node) {
4206
4207  // If the only non-undef value is the low element, turn this into a
4208  // SCALAR_TO_VECTOR node.  If this is { X, X, X, X }, determine X.
4209  unsigned NumElems = Node->getNumOperands();
4210  bool isOnlyLowElement = true;
4211  SDOperand SplatValue = Node->getOperand(0);
4212  std::map<SDOperand, std::vector<unsigned> > Values;
4213  Values[SplatValue].push_back(0);
4214  bool isConstant = true;
4215  if (!isa<ConstantFPSDNode>(SplatValue) && !isa<ConstantSDNode>(SplatValue) &&
4216      SplatValue.getOpcode() != ISD::UNDEF)
4217    isConstant = false;
4218
4219  for (unsigned i = 1; i < NumElems; ++i) {
4220    SDOperand V = Node->getOperand(i);
4221    Values[V].push_back(i);
4222    if (V.getOpcode() != ISD::UNDEF)
4223      isOnlyLowElement = false;
4224    if (SplatValue != V)
4225      SplatValue = SDOperand(0,0);
4226
4227    // If this isn't a constant element or an undef, we can't use a constant
4228    // pool load.
4229    if (!isa<ConstantFPSDNode>(V) && !isa<ConstantSDNode>(V) &&
4230        V.getOpcode() != ISD::UNDEF)
4231      isConstant = false;
4232  }
4233
4234  if (isOnlyLowElement) {
4235    // If the low element is an undef too, then this whole things is an undef.
4236    if (Node->getOperand(0).getOpcode() == ISD::UNDEF)
4237      return DAG.getNode(ISD::UNDEF, Node->getValueType(0));
4238    // Otherwise, turn this into a scalar_to_vector node.
4239    return DAG.getNode(ISD::SCALAR_TO_VECTOR, Node->getValueType(0),
4240                       Node->getOperand(0));
4241  }
4242
4243  // If all elements are constants, create a load from the constant pool.
4244  if (isConstant) {
4245    MVT::ValueType VT = Node->getValueType(0);
4246    const Type *OpNTy =
4247      MVT::getTypeForValueType(Node->getOperand(0).getValueType());
4248    std::vector<Constant*> CV;
4249    for (unsigned i = 0, e = NumElems; i != e; ++i) {
4250      if (ConstantFPSDNode *V =
4251          dyn_cast<ConstantFPSDNode>(Node->getOperand(i))) {
4252        CV.push_back(ConstantFP::get(OpNTy, V->getValueAPF()));
4253      } else if (ConstantSDNode *V =
4254                 dyn_cast<ConstantSDNode>(Node->getOperand(i))) {
4255        CV.push_back(ConstantInt::get(OpNTy, V->getValue()));
4256      } else {
4257        assert(Node->getOperand(i).getOpcode() == ISD::UNDEF);
4258        CV.push_back(UndefValue::get(OpNTy));
4259      }
4260    }
4261    Constant *CP = ConstantVector::get(CV);
4262    SDOperand CPIdx = DAG.getConstantPool(CP, TLI.getPointerTy());
4263    return DAG.getLoad(VT, DAG.getEntryNode(), CPIdx, NULL, 0);
4264  }
4265
4266  if (SplatValue.Val) {   // Splat of one value?
4267    // Build the shuffle constant vector: <0, 0, 0, 0>
4268    MVT::ValueType MaskVT =
4269      MVT::getIntVectorWithNumElements(NumElems);
4270    SDOperand Zero = DAG.getConstant(0, MVT::getVectorElementType(MaskVT));
4271    std::vector<SDOperand> ZeroVec(NumElems, Zero);
4272    SDOperand SplatMask = DAG.getNode(ISD::BUILD_VECTOR, MaskVT,
4273                                      &ZeroVec[0], ZeroVec.size());
4274
4275    // If the target supports VECTOR_SHUFFLE and this shuffle mask, use it.
4276    if (isShuffleLegal(Node->getValueType(0), SplatMask)) {
4277      // Get the splatted value into the low element of a vector register.
4278      SDOperand LowValVec =
4279        DAG.getNode(ISD::SCALAR_TO_VECTOR, Node->getValueType(0), SplatValue);
4280
4281      // Return shuffle(LowValVec, undef, <0,0,0,0>)
4282      return DAG.getNode(ISD::VECTOR_SHUFFLE, Node->getValueType(0), LowValVec,
4283                         DAG.getNode(ISD::UNDEF, Node->getValueType(0)),
4284                         SplatMask);
4285    }
4286  }
4287
4288  // If there are only two unique elements, we may be able to turn this into a
4289  // vector shuffle.
4290  if (Values.size() == 2) {
4291    // Build the shuffle constant vector: e.g. <0, 4, 0, 4>
4292    MVT::ValueType MaskVT =
4293      MVT::getIntVectorWithNumElements(NumElems);
4294    std::vector<SDOperand> MaskVec(NumElems);
4295    unsigned i = 0;
4296    for (std::map<SDOperand,std::vector<unsigned> >::iterator I=Values.begin(),
4297           E = Values.end(); I != E; ++I) {
4298      for (std::vector<unsigned>::iterator II = I->second.begin(),
4299             EE = I->second.end(); II != EE; ++II)
4300        MaskVec[*II] = DAG.getConstant(i, MVT::getVectorElementType(MaskVT));
4301      i += NumElems;
4302    }
4303    SDOperand ShuffleMask = DAG.getNode(ISD::BUILD_VECTOR, MaskVT,
4304                                        &MaskVec[0], MaskVec.size());
4305
4306    // If the target supports VECTOR_SHUFFLE and this shuffle mask, use it.
4307    if (TLI.isOperationLegal(ISD::SCALAR_TO_VECTOR, Node->getValueType(0)) &&
4308        isShuffleLegal(Node->getValueType(0), ShuffleMask)) {
4309      SmallVector<SDOperand, 8> Ops;
4310      for(std::map<SDOperand,std::vector<unsigned> >::iterator I=Values.begin(),
4311            E = Values.end(); I != E; ++I) {
4312        SDOperand Op = DAG.getNode(ISD::SCALAR_TO_VECTOR, Node->getValueType(0),
4313                                   I->first);
4314        Ops.push_back(Op);
4315      }
4316      Ops.push_back(ShuffleMask);
4317
4318      // Return shuffle(LoValVec, HiValVec, <0,1,0,1>)
4319      return DAG.getNode(ISD::VECTOR_SHUFFLE, Node->getValueType(0),
4320                         &Ops[0], Ops.size());
4321    }
4322  }
4323
4324  // Otherwise, we can't handle this case efficiently.  Allocate a sufficiently
4325  // aligned object on the stack, store each element into it, then load
4326  // the result as a vector.
4327  MVT::ValueType VT = Node->getValueType(0);
4328  // Create the stack frame object.
4329  SDOperand FIPtr = CreateStackTemporary(VT);
4330
4331  // Emit a store of each element to the stack slot.
4332  SmallVector<SDOperand, 8> Stores;
4333  unsigned TypeByteSize =
4334    MVT::getSizeInBits(Node->getOperand(0).getValueType())/8;
4335  // Store (in the right endianness) the elements to memory.
4336  for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
4337    // Ignore undef elements.
4338    if (Node->getOperand(i).getOpcode() == ISD::UNDEF) continue;
4339
4340    unsigned Offset = TypeByteSize*i;
4341
4342    SDOperand Idx = DAG.getConstant(Offset, FIPtr.getValueType());
4343    Idx = DAG.getNode(ISD::ADD, FIPtr.getValueType(), FIPtr, Idx);
4344
4345    Stores.push_back(DAG.getStore(DAG.getEntryNode(), Node->getOperand(i), Idx,
4346                                  NULL, 0));
4347  }
4348
4349  SDOperand StoreChain;
4350  if (!Stores.empty())    // Not all undef elements?
4351    StoreChain = DAG.getNode(ISD::TokenFactor, MVT::Other,
4352                             &Stores[0], Stores.size());
4353  else
4354    StoreChain = DAG.getEntryNode();
4355
4356  // Result is a load from the stack slot.
4357  return DAG.getLoad(VT, StoreChain, FIPtr, NULL, 0);
4358}
4359
4360/// CreateStackTemporary - Create a stack temporary, suitable for holding the
4361/// specified value type.
4362SDOperand SelectionDAGLegalize::CreateStackTemporary(MVT::ValueType VT) {
4363  MachineFrameInfo *FrameInfo = DAG.getMachineFunction().getFrameInfo();
4364  unsigned ByteSize = MVT::getSizeInBits(VT)/8;
4365  const Type *Ty = MVT::getTypeForValueType(VT);
4366  unsigned StackAlign = (unsigned)TLI.getTargetData()->getPrefTypeAlignment(Ty);
4367  int FrameIdx = FrameInfo->CreateStackObject(ByteSize, StackAlign);
4368  return DAG.getFrameIndex(FrameIdx, TLI.getPointerTy());
4369}
4370
4371void SelectionDAGLegalize::ExpandShiftParts(unsigned NodeOp,
4372                                            SDOperand Op, SDOperand Amt,
4373                                            SDOperand &Lo, SDOperand &Hi) {
4374  // Expand the subcomponents.
4375  SDOperand LHSL, LHSH;
4376  ExpandOp(Op, LHSL, LHSH);
4377
4378  SDOperand Ops[] = { LHSL, LHSH, Amt };
4379  MVT::ValueType VT = LHSL.getValueType();
4380  Lo = DAG.getNode(NodeOp, DAG.getNodeValueTypes(VT, VT), 2, Ops, 3);
4381  Hi = Lo.getValue(1);
4382}
4383
4384
4385/// ExpandShift - Try to find a clever way to expand this shift operation out to
4386/// smaller elements.  If we can't find a way that is more efficient than a
4387/// libcall on this target, return false.  Otherwise, return true with the
4388/// low-parts expanded into Lo and Hi.
4389bool SelectionDAGLegalize::ExpandShift(unsigned Opc, SDOperand Op,SDOperand Amt,
4390                                       SDOperand &Lo, SDOperand &Hi) {
4391  assert((Opc == ISD::SHL || Opc == ISD::SRA || Opc == ISD::SRL) &&
4392         "This is not a shift!");
4393
4394  MVT::ValueType NVT = TLI.getTypeToTransformTo(Op.getValueType());
4395  SDOperand ShAmt = LegalizeOp(Amt);
4396  MVT::ValueType ShTy = ShAmt.getValueType();
4397  unsigned VTBits = MVT::getSizeInBits(Op.getValueType());
4398  unsigned NVTBits = MVT::getSizeInBits(NVT);
4399
4400  // Handle the case when Amt is an immediate.  Other cases are currently broken
4401  // and are disabled.
4402  if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Amt.Val)) {
4403    unsigned Cst = CN->getValue();
4404    // Expand the incoming operand to be shifted, so that we have its parts
4405    SDOperand InL, InH;
4406    ExpandOp(Op, InL, InH);
4407    switch(Opc) {
4408    case ISD::SHL:
4409      if (Cst > VTBits) {
4410        Lo = DAG.getConstant(0, NVT);
4411        Hi = DAG.getConstant(0, NVT);
4412      } else if (Cst > NVTBits) {
4413        Lo = DAG.getConstant(0, NVT);
4414        Hi = DAG.getNode(ISD::SHL, NVT, InL, DAG.getConstant(Cst-NVTBits,ShTy));
4415      } else if (Cst == NVTBits) {
4416        Lo = DAG.getConstant(0, NVT);
4417        Hi = InL;
4418      } else {
4419        Lo = DAG.getNode(ISD::SHL, NVT, InL, DAG.getConstant(Cst, ShTy));
4420        Hi = DAG.getNode(ISD::OR, NVT,
4421           DAG.getNode(ISD::SHL, NVT, InH, DAG.getConstant(Cst, ShTy)),
4422           DAG.getNode(ISD::SRL, NVT, InL, DAG.getConstant(NVTBits-Cst, ShTy)));
4423      }
4424      return true;
4425    case ISD::SRL:
4426      if (Cst > VTBits) {
4427        Lo = DAG.getConstant(0, NVT);
4428        Hi = DAG.getConstant(0, NVT);
4429      } else if (Cst > NVTBits) {
4430        Lo = DAG.getNode(ISD::SRL, NVT, InH, DAG.getConstant(Cst-NVTBits,ShTy));
4431        Hi = DAG.getConstant(0, NVT);
4432      } else if (Cst == NVTBits) {
4433        Lo = InH;
4434        Hi = DAG.getConstant(0, NVT);
4435      } else {
4436        Lo = DAG.getNode(ISD::OR, NVT,
4437           DAG.getNode(ISD::SRL, NVT, InL, DAG.getConstant(Cst, ShTy)),
4438           DAG.getNode(ISD::SHL, NVT, InH, DAG.getConstant(NVTBits-Cst, ShTy)));
4439        Hi = DAG.getNode(ISD::SRL, NVT, InH, DAG.getConstant(Cst, ShTy));
4440      }
4441      return true;
4442    case ISD::SRA:
4443      if (Cst > VTBits) {
4444        Hi = Lo = DAG.getNode(ISD::SRA, NVT, InH,
4445                              DAG.getConstant(NVTBits-1, ShTy));
4446      } else if (Cst > NVTBits) {
4447        Lo = DAG.getNode(ISD::SRA, NVT, InH,
4448                           DAG.getConstant(Cst-NVTBits, ShTy));
4449        Hi = DAG.getNode(ISD::SRA, NVT, InH,
4450                              DAG.getConstant(NVTBits-1, ShTy));
4451      } else if (Cst == NVTBits) {
4452        Lo = InH;
4453        Hi = DAG.getNode(ISD::SRA, NVT, InH,
4454                              DAG.getConstant(NVTBits-1, ShTy));
4455      } else {
4456        Lo = DAG.getNode(ISD::OR, NVT,
4457           DAG.getNode(ISD::SRL, NVT, InL, DAG.getConstant(Cst, ShTy)),
4458           DAG.getNode(ISD::SHL, NVT, InH, DAG.getConstant(NVTBits-Cst, ShTy)));
4459        Hi = DAG.getNode(ISD::SRA, NVT, InH, DAG.getConstant(Cst, ShTy));
4460      }
4461      return true;
4462    }
4463  }
4464
4465  // Okay, the shift amount isn't constant.  However, if we can tell that it is
4466  // >= 32 or < 32, we can still simplify it, without knowing the actual value.
4467  uint64_t Mask = NVTBits, KnownZero, KnownOne;
4468  DAG.ComputeMaskedBits(Amt, Mask, KnownZero, KnownOne);
4469
4470  // If we know that the high bit of the shift amount is one, then we can do
4471  // this as a couple of simple shifts.
4472  if (KnownOne & Mask) {
4473    // Mask out the high bit, which we know is set.
4474    Amt = DAG.getNode(ISD::AND, Amt.getValueType(), Amt,
4475                      DAG.getConstant(NVTBits-1, Amt.getValueType()));
4476
4477    // Expand the incoming operand to be shifted, so that we have its parts
4478    SDOperand InL, InH;
4479    ExpandOp(Op, InL, InH);
4480    switch(Opc) {
4481    case ISD::SHL:
4482      Lo = DAG.getConstant(0, NVT);              // Low part is zero.
4483      Hi = DAG.getNode(ISD::SHL, NVT, InL, Amt); // High part from Lo part.
4484      return true;
4485    case ISD::SRL:
4486      Hi = DAG.getConstant(0, NVT);              // Hi part is zero.
4487      Lo = DAG.getNode(ISD::SRL, NVT, InH, Amt); // Lo part from Hi part.
4488      return true;
4489    case ISD::SRA:
4490      Hi = DAG.getNode(ISD::SRA, NVT, InH,       // Sign extend high part.
4491                       DAG.getConstant(NVTBits-1, Amt.getValueType()));
4492      Lo = DAG.getNode(ISD::SRA, NVT, InH, Amt); // Lo part from Hi part.
4493      return true;
4494    }
4495  }
4496
4497  // If we know that the high bit of the shift amount is zero, then we can do
4498  // this as a couple of simple shifts.
4499  if (KnownZero & Mask) {
4500    // Compute 32-amt.
4501    SDOperand Amt2 = DAG.getNode(ISD::SUB, Amt.getValueType(),
4502                                 DAG.getConstant(NVTBits, Amt.getValueType()),
4503                                 Amt);
4504
4505    // Expand the incoming operand to be shifted, so that we have its parts
4506    SDOperand InL, InH;
4507    ExpandOp(Op, InL, InH);
4508    switch(Opc) {
4509    case ISD::SHL:
4510      Lo = DAG.getNode(ISD::SHL, NVT, InL, Amt);
4511      Hi = DAG.getNode(ISD::OR, NVT,
4512                       DAG.getNode(ISD::SHL, NVT, InH, Amt),
4513                       DAG.getNode(ISD::SRL, NVT, InL, Amt2));
4514      return true;
4515    case ISD::SRL:
4516      Hi = DAG.getNode(ISD::SRL, NVT, InH, Amt);
4517      Lo = DAG.getNode(ISD::OR, NVT,
4518                       DAG.getNode(ISD::SRL, NVT, InL, Amt),
4519                       DAG.getNode(ISD::SHL, NVT, InH, Amt2));
4520      return true;
4521    case ISD::SRA:
4522      Hi = DAG.getNode(ISD::SRA, NVT, InH, Amt);
4523      Lo = DAG.getNode(ISD::OR, NVT,
4524                       DAG.getNode(ISD::SRL, NVT, InL, Amt),
4525                       DAG.getNode(ISD::SHL, NVT, InH, Amt2));
4526      return true;
4527    }
4528  }
4529
4530  return false;
4531}
4532
4533
4534// ExpandLibCall - Expand a node into a call to a libcall.  If the result value
4535// does not fit into a register, return the lo part and set the hi part to the
4536// by-reg argument.  If it does fit into a single register, return the result
4537// and leave the Hi part unset.
4538SDOperand SelectionDAGLegalize::ExpandLibCall(const char *Name, SDNode *Node,
4539                                              bool isSigned, SDOperand &Hi) {
4540  assert(!IsLegalizingCall && "Cannot overlap legalization of calls!");
4541  // The input chain to this libcall is the entry node of the function.
4542  // Legalizing the call will automatically add the previous call to the
4543  // dependence.
4544  SDOperand InChain = DAG.getEntryNode();
4545
4546  TargetLowering::ArgListTy Args;
4547  TargetLowering::ArgListEntry Entry;
4548  for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
4549    MVT::ValueType ArgVT = Node->getOperand(i).getValueType();
4550    const Type *ArgTy = MVT::getTypeForValueType(ArgVT);
4551    Entry.Node = Node->getOperand(i); Entry.Ty = ArgTy;
4552    Entry.isSExt = isSigned;
4553    Args.push_back(Entry);
4554  }
4555  SDOperand Callee = DAG.getExternalSymbol(Name, TLI.getPointerTy());
4556
4557  // Splice the libcall in wherever FindInputOutputChains tells us to.
4558  const Type *RetTy = MVT::getTypeForValueType(Node->getValueType(0));
4559  std::pair<SDOperand,SDOperand> CallInfo =
4560    TLI.LowerCallTo(InChain, RetTy, isSigned, false, CallingConv::C, false,
4561                    Callee, Args, DAG);
4562
4563  // Legalize the call sequence, starting with the chain.  This will advance
4564  // the LastCALLSEQ_END to the legalized version of the CALLSEQ_END node that
4565  // was added by LowerCallTo (guaranteeing proper serialization of calls).
4566  LegalizeOp(CallInfo.second);
4567  SDOperand Result;
4568  switch (getTypeAction(CallInfo.first.getValueType())) {
4569  default: assert(0 && "Unknown thing");
4570  case Legal:
4571    Result = CallInfo.first;
4572    break;
4573  case Expand:
4574    ExpandOp(CallInfo.first, Result, Hi);
4575    break;
4576  }
4577  return Result;
4578}
4579
4580
4581/// ExpandIntToFP - Expand a [US]INT_TO_FP operation.
4582///
4583SDOperand SelectionDAGLegalize::
4584ExpandIntToFP(bool isSigned, MVT::ValueType DestTy, SDOperand Source) {
4585  assert(getTypeAction(Source.getValueType()) == Expand &&
4586         "This is not an expansion!");
4587  assert(Source.getValueType() == MVT::i64 && "Only handle expand from i64!");
4588
4589  if (!isSigned) {
4590    assert(Source.getValueType() == MVT::i64 &&
4591           "This only works for 64-bit -> FP");
4592    // The 64-bit value loaded will be incorrectly if the 'sign bit' of the
4593    // incoming integer is set.  To handle this, we dynamically test to see if
4594    // it is set, and, if so, add a fudge factor.
4595    SDOperand Lo, Hi;
4596    ExpandOp(Source, Lo, Hi);
4597
4598    // If this is unsigned, and not supported, first perform the conversion to
4599    // signed, then adjust the result if the sign bit is set.
4600    SDOperand SignedConv = ExpandIntToFP(true, DestTy,
4601                   DAG.getNode(ISD::BUILD_PAIR, Source.getValueType(), Lo, Hi));
4602
4603    SDOperand SignSet = DAG.getSetCC(TLI.getSetCCResultTy(), Hi,
4604                                     DAG.getConstant(0, Hi.getValueType()),
4605                                     ISD::SETLT);
4606    SDOperand Zero = getIntPtrConstant(0), Four = getIntPtrConstant(4);
4607    SDOperand CstOffset = DAG.getNode(ISD::SELECT, Zero.getValueType(),
4608                                      SignSet, Four, Zero);
4609    uint64_t FF = 0x5f800000ULL;
4610    if (TLI.isLittleEndian()) FF <<= 32;
4611    static Constant *FudgeFactor = ConstantInt::get(Type::Int64Ty, FF);
4612
4613    SDOperand CPIdx = DAG.getConstantPool(FudgeFactor, TLI.getPointerTy());
4614    CPIdx = DAG.getNode(ISD::ADD, TLI.getPointerTy(), CPIdx, CstOffset);
4615    SDOperand FudgeInReg;
4616    if (DestTy == MVT::f32)
4617      FudgeInReg = DAG.getLoad(MVT::f32, DAG.getEntryNode(), CPIdx, NULL, 0);
4618    else if (MVT::getSizeInBits(DestTy) > MVT::getSizeInBits(MVT::f32))
4619      // FIXME: Avoid the extend by construction the right constantpool?
4620      FudgeInReg = DAG.getExtLoad(ISD::EXTLOAD, DestTy, DAG.getEntryNode(),
4621                                  CPIdx, NULL, 0, MVT::f32);
4622    else
4623      assert(0 && "Unexpected conversion");
4624
4625    MVT::ValueType SCVT = SignedConv.getValueType();
4626    if (SCVT != DestTy) {
4627      // Destination type needs to be expanded as well. The FADD now we are
4628      // constructing will be expanded into a libcall.
4629      if (MVT::getSizeInBits(SCVT) != MVT::getSizeInBits(DestTy)) {
4630        assert(SCVT == MVT::i32 && DestTy == MVT::f64);
4631        SignedConv = DAG.getNode(ISD::BUILD_PAIR, MVT::i64,
4632                                 SignedConv, SignedConv.getValue(1));
4633      }
4634      SignedConv = DAG.getNode(ISD::BIT_CONVERT, DestTy, SignedConv);
4635    }
4636    return DAG.getNode(ISD::FADD, DestTy, SignedConv, FudgeInReg);
4637  }
4638
4639  // Check to see if the target has a custom way to lower this.  If so, use it.
4640  switch (TLI.getOperationAction(ISD::SINT_TO_FP, Source.getValueType())) {
4641  default: assert(0 && "This action not implemented for this operation!");
4642  case TargetLowering::Legal:
4643  case TargetLowering::Expand:
4644    break;   // This case is handled below.
4645  case TargetLowering::Custom: {
4646    SDOperand NV = TLI.LowerOperation(DAG.getNode(ISD::SINT_TO_FP, DestTy,
4647                                                  Source), DAG);
4648    if (NV.Val)
4649      return LegalizeOp(NV);
4650    break;   // The target decided this was legal after all
4651  }
4652  }
4653
4654  // Expand the source, then glue it back together for the call.  We must expand
4655  // the source in case it is shared (this pass of legalize must traverse it).
4656  SDOperand SrcLo, SrcHi;
4657  ExpandOp(Source, SrcLo, SrcHi);
4658  Source = DAG.getNode(ISD::BUILD_PAIR, Source.getValueType(), SrcLo, SrcHi);
4659
4660  RTLIB::Libcall LC;
4661  if (DestTy == MVT::f32)
4662    LC = RTLIB::SINTTOFP_I64_F32;
4663  else {
4664    assert(DestTy == MVT::f64 && "Unknown fp value type!");
4665    LC = RTLIB::SINTTOFP_I64_F64;
4666  }
4667
4668  assert(TLI.getLibcallName(LC) && "Don't know how to expand this SINT_TO_FP!");
4669  Source = DAG.getNode(ISD::SINT_TO_FP, DestTy, Source);
4670  SDOperand UnusedHiPart;
4671  return ExpandLibCall(TLI.getLibcallName(LC), Source.Val, isSigned,
4672                       UnusedHiPart);
4673}
4674
4675/// ExpandLegalINT_TO_FP - This function is responsible for legalizing a
4676/// INT_TO_FP operation of the specified operand when the target requests that
4677/// we expand it.  At this point, we know that the result and operand types are
4678/// legal for the target.
4679SDOperand SelectionDAGLegalize::ExpandLegalINT_TO_FP(bool isSigned,
4680                                                     SDOperand Op0,
4681                                                     MVT::ValueType DestVT) {
4682  if (Op0.getValueType() == MVT::i32) {
4683    // simple 32-bit [signed|unsigned] integer to float/double expansion
4684
4685    // get the stack frame index of a 8 byte buffer, pessimistically aligned
4686    MachineFunction &MF = DAG.getMachineFunction();
4687    const Type *F64Type = MVT::getTypeForValueType(MVT::f64);
4688    unsigned StackAlign =
4689      (unsigned)TLI.getTargetData()->getPrefTypeAlignment(F64Type);
4690    int SSFI = MF.getFrameInfo()->CreateStackObject(8, StackAlign);
4691    // get address of 8 byte buffer
4692    SDOperand StackSlot = DAG.getFrameIndex(SSFI, TLI.getPointerTy());
4693    // word offset constant for Hi/Lo address computation
4694    SDOperand WordOff = DAG.getConstant(sizeof(int), TLI.getPointerTy());
4695    // set up Hi and Lo (into buffer) address based on endian
4696    SDOperand Hi = StackSlot;
4697    SDOperand Lo = DAG.getNode(ISD::ADD, TLI.getPointerTy(), StackSlot,WordOff);
4698    if (TLI.isLittleEndian())
4699      std::swap(Hi, Lo);
4700
4701    // if signed map to unsigned space
4702    SDOperand Op0Mapped;
4703    if (isSigned) {
4704      // constant used to invert sign bit (signed to unsigned mapping)
4705      SDOperand SignBit = DAG.getConstant(0x80000000u, MVT::i32);
4706      Op0Mapped = DAG.getNode(ISD::XOR, MVT::i32, Op0, SignBit);
4707    } else {
4708      Op0Mapped = Op0;
4709    }
4710    // store the lo of the constructed double - based on integer input
4711    SDOperand Store1 = DAG.getStore(DAG.getEntryNode(),
4712                                    Op0Mapped, Lo, NULL, 0);
4713    // initial hi portion of constructed double
4714    SDOperand InitialHi = DAG.getConstant(0x43300000u, MVT::i32);
4715    // store the hi of the constructed double - biased exponent
4716    SDOperand Store2=DAG.getStore(Store1, InitialHi, Hi, NULL, 0);
4717    // load the constructed double
4718    SDOperand Load = DAG.getLoad(MVT::f64, Store2, StackSlot, NULL, 0);
4719    // FP constant to bias correct the final result
4720    SDOperand Bias = DAG.getConstantFP(isSigned ?
4721                                            BitsToDouble(0x4330000080000000ULL)
4722                                          : BitsToDouble(0x4330000000000000ULL),
4723                                     MVT::f64);
4724    // subtract the bias
4725    SDOperand Sub = DAG.getNode(ISD::FSUB, MVT::f64, Load, Bias);
4726    // final result
4727    SDOperand Result;
4728    // handle final rounding
4729    if (DestVT == MVT::f64) {
4730      // do nothing
4731      Result = Sub;
4732    } else if (MVT::getSizeInBits(DestVT) < MVT::getSizeInBits(MVT::f64)) {
4733      Result = DAG.getNode(ISD::FP_ROUND, DestVT, Sub);
4734    } else if (MVT::getSizeInBits(DestVT) > MVT::getSizeInBits(MVT::f64)) {
4735      Result = DAG.getNode(ISD::FP_EXTEND, DestVT, Sub);
4736    }
4737    return Result;
4738  }
4739  assert(!isSigned && "Legalize cannot Expand SINT_TO_FP for i64 yet");
4740  SDOperand Tmp1 = DAG.getNode(ISD::SINT_TO_FP, DestVT, Op0);
4741
4742  SDOperand SignSet = DAG.getSetCC(TLI.getSetCCResultTy(), Op0,
4743                                   DAG.getConstant(0, Op0.getValueType()),
4744                                   ISD::SETLT);
4745  SDOperand Zero = getIntPtrConstant(0), Four = getIntPtrConstant(4);
4746  SDOperand CstOffset = DAG.getNode(ISD::SELECT, Zero.getValueType(),
4747                                    SignSet, Four, Zero);
4748
4749  // If the sign bit of the integer is set, the large number will be treated
4750  // as a negative number.  To counteract this, the dynamic code adds an
4751  // offset depending on the data type.
4752  uint64_t FF;
4753  switch (Op0.getValueType()) {
4754  default: assert(0 && "Unsupported integer type!");
4755  case MVT::i8 : FF = 0x43800000ULL; break;  // 2^8  (as a float)
4756  case MVT::i16: FF = 0x47800000ULL; break;  // 2^16 (as a float)
4757  case MVT::i32: FF = 0x4F800000ULL; break;  // 2^32 (as a float)
4758  case MVT::i64: FF = 0x5F800000ULL; break;  // 2^64 (as a float)
4759  }
4760  if (TLI.isLittleEndian()) FF <<= 32;
4761  static Constant *FudgeFactor = ConstantInt::get(Type::Int64Ty, FF);
4762
4763  SDOperand CPIdx = DAG.getConstantPool(FudgeFactor, TLI.getPointerTy());
4764  CPIdx = DAG.getNode(ISD::ADD, TLI.getPointerTy(), CPIdx, CstOffset);
4765  SDOperand FudgeInReg;
4766  if (DestVT == MVT::f32)
4767    FudgeInReg = DAG.getLoad(MVT::f32, DAG.getEntryNode(), CPIdx, NULL, 0);
4768  else {
4769    assert(DestVT == MVT::f64 && "Unexpected conversion");
4770    FudgeInReg = LegalizeOp(DAG.getExtLoad(ISD::EXTLOAD, MVT::f64,
4771                                           DAG.getEntryNode(), CPIdx,
4772                                           NULL, 0, MVT::f32));
4773  }
4774
4775  return DAG.getNode(ISD::FADD, DestVT, Tmp1, FudgeInReg);
4776}
4777
4778/// PromoteLegalINT_TO_FP - This function is responsible for legalizing a
4779/// *INT_TO_FP operation of the specified operand when the target requests that
4780/// we promote it.  At this point, we know that the result and operand types are
4781/// legal for the target, and that there is a legal UINT_TO_FP or SINT_TO_FP
4782/// operation that takes a larger input.
4783SDOperand SelectionDAGLegalize::PromoteLegalINT_TO_FP(SDOperand LegalOp,
4784                                                      MVT::ValueType DestVT,
4785                                                      bool isSigned) {
4786  // First step, figure out the appropriate *INT_TO_FP operation to use.
4787  MVT::ValueType NewInTy = LegalOp.getValueType();
4788
4789  unsigned OpToUse = 0;
4790
4791  // Scan for the appropriate larger type to use.
4792  while (1) {
4793    NewInTy = (MVT::ValueType)(NewInTy+1);
4794    assert(MVT::isInteger(NewInTy) && "Ran out of possibilities!");
4795
4796    // If the target supports SINT_TO_FP of this type, use it.
4797    switch (TLI.getOperationAction(ISD::SINT_TO_FP, NewInTy)) {
4798      default: break;
4799      case TargetLowering::Legal:
4800        if (!TLI.isTypeLegal(NewInTy))
4801          break;  // Can't use this datatype.
4802        // FALL THROUGH.
4803      case TargetLowering::Custom:
4804        OpToUse = ISD::SINT_TO_FP;
4805        break;
4806    }
4807    if (OpToUse) break;
4808    if (isSigned) continue;
4809
4810    // If the target supports UINT_TO_FP of this type, use it.
4811    switch (TLI.getOperationAction(ISD::UINT_TO_FP, NewInTy)) {
4812      default: break;
4813      case TargetLowering::Legal:
4814        if (!TLI.isTypeLegal(NewInTy))
4815          break;  // Can't use this datatype.
4816        // FALL THROUGH.
4817      case TargetLowering::Custom:
4818        OpToUse = ISD::UINT_TO_FP;
4819        break;
4820    }
4821    if (OpToUse) break;
4822
4823    // Otherwise, try a larger type.
4824  }
4825
4826  // Okay, we found the operation and type to use.  Zero extend our input to the
4827  // desired type then run the operation on it.
4828  return DAG.getNode(OpToUse, DestVT,
4829                     DAG.getNode(isSigned ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND,
4830                                 NewInTy, LegalOp));
4831}
4832
4833/// PromoteLegalFP_TO_INT - This function is responsible for legalizing a
4834/// FP_TO_*INT operation of the specified operand when the target requests that
4835/// we promote it.  At this point, we know that the result and operand types are
4836/// legal for the target, and that there is a legal FP_TO_UINT or FP_TO_SINT
4837/// operation that returns a larger result.
4838SDOperand SelectionDAGLegalize::PromoteLegalFP_TO_INT(SDOperand LegalOp,
4839                                                      MVT::ValueType DestVT,
4840                                                      bool isSigned) {
4841  // First step, figure out the appropriate FP_TO*INT operation to use.
4842  MVT::ValueType NewOutTy = DestVT;
4843
4844  unsigned OpToUse = 0;
4845
4846  // Scan for the appropriate larger type to use.
4847  while (1) {
4848    NewOutTy = (MVT::ValueType)(NewOutTy+1);
4849    assert(MVT::isInteger(NewOutTy) && "Ran out of possibilities!");
4850
4851    // If the target supports FP_TO_SINT returning this type, use it.
4852    switch (TLI.getOperationAction(ISD::FP_TO_SINT, NewOutTy)) {
4853    default: break;
4854    case TargetLowering::Legal:
4855      if (!TLI.isTypeLegal(NewOutTy))
4856        break;  // Can't use this datatype.
4857      // FALL THROUGH.
4858    case TargetLowering::Custom:
4859      OpToUse = ISD::FP_TO_SINT;
4860      break;
4861    }
4862    if (OpToUse) break;
4863
4864    // If the target supports FP_TO_UINT of this type, use it.
4865    switch (TLI.getOperationAction(ISD::FP_TO_UINT, NewOutTy)) {
4866    default: break;
4867    case TargetLowering::Legal:
4868      if (!TLI.isTypeLegal(NewOutTy))
4869        break;  // Can't use this datatype.
4870      // FALL THROUGH.
4871    case TargetLowering::Custom:
4872      OpToUse = ISD::FP_TO_UINT;
4873      break;
4874    }
4875    if (OpToUse) break;
4876
4877    // Otherwise, try a larger type.
4878  }
4879
4880  // Okay, we found the operation and type to use.  Truncate the result of the
4881  // extended FP_TO_*INT operation to the desired size.
4882  return DAG.getNode(ISD::TRUNCATE, DestVT,
4883                     DAG.getNode(OpToUse, NewOutTy, LegalOp));
4884}
4885
4886/// ExpandBSWAP - Open code the operations for BSWAP of the specified operation.
4887///
4888SDOperand SelectionDAGLegalize::ExpandBSWAP(SDOperand Op) {
4889  MVT::ValueType VT = Op.getValueType();
4890  MVT::ValueType SHVT = TLI.getShiftAmountTy();
4891  SDOperand Tmp1, Tmp2, Tmp3, Tmp4, Tmp5, Tmp6, Tmp7, Tmp8;
4892  switch (VT) {
4893  default: assert(0 && "Unhandled Expand type in BSWAP!"); abort();
4894  case MVT::i16:
4895    Tmp2 = DAG.getNode(ISD::SHL, VT, Op, DAG.getConstant(8, SHVT));
4896    Tmp1 = DAG.getNode(ISD::SRL, VT, Op, DAG.getConstant(8, SHVT));
4897    return DAG.getNode(ISD::OR, VT, Tmp1, Tmp2);
4898  case MVT::i32:
4899    Tmp4 = DAG.getNode(ISD::SHL, VT, Op, DAG.getConstant(24, SHVT));
4900    Tmp3 = DAG.getNode(ISD::SHL, VT, Op, DAG.getConstant(8, SHVT));
4901    Tmp2 = DAG.getNode(ISD::SRL, VT, Op, DAG.getConstant(8, SHVT));
4902    Tmp1 = DAG.getNode(ISD::SRL, VT, Op, DAG.getConstant(24, SHVT));
4903    Tmp3 = DAG.getNode(ISD::AND, VT, Tmp3, DAG.getConstant(0xFF0000, VT));
4904    Tmp2 = DAG.getNode(ISD::AND, VT, Tmp2, DAG.getConstant(0xFF00, VT));
4905    Tmp4 = DAG.getNode(ISD::OR, VT, Tmp4, Tmp3);
4906    Tmp2 = DAG.getNode(ISD::OR, VT, Tmp2, Tmp1);
4907    return DAG.getNode(ISD::OR, VT, Tmp4, Tmp2);
4908  case MVT::i64:
4909    Tmp8 = DAG.getNode(ISD::SHL, VT, Op, DAG.getConstant(56, SHVT));
4910    Tmp7 = DAG.getNode(ISD::SHL, VT, Op, DAG.getConstant(40, SHVT));
4911    Tmp6 = DAG.getNode(ISD::SHL, VT, Op, DAG.getConstant(24, SHVT));
4912    Tmp5 = DAG.getNode(ISD::SHL, VT, Op, DAG.getConstant(8, SHVT));
4913    Tmp4 = DAG.getNode(ISD::SRL, VT, Op, DAG.getConstant(8, SHVT));
4914    Tmp3 = DAG.getNode(ISD::SRL, VT, Op, DAG.getConstant(24, SHVT));
4915    Tmp2 = DAG.getNode(ISD::SRL, VT, Op, DAG.getConstant(40, SHVT));
4916    Tmp1 = DAG.getNode(ISD::SRL, VT, Op, DAG.getConstant(56, SHVT));
4917    Tmp7 = DAG.getNode(ISD::AND, VT, Tmp7, DAG.getConstant(255ULL<<48, VT));
4918    Tmp6 = DAG.getNode(ISD::AND, VT, Tmp6, DAG.getConstant(255ULL<<40, VT));
4919    Tmp5 = DAG.getNode(ISD::AND, VT, Tmp5, DAG.getConstant(255ULL<<32, VT));
4920    Tmp4 = DAG.getNode(ISD::AND, VT, Tmp4, DAG.getConstant(255ULL<<24, VT));
4921    Tmp3 = DAG.getNode(ISD::AND, VT, Tmp3, DAG.getConstant(255ULL<<16, VT));
4922    Tmp2 = DAG.getNode(ISD::AND, VT, Tmp2, DAG.getConstant(255ULL<<8 , VT));
4923    Tmp8 = DAG.getNode(ISD::OR, VT, Tmp8, Tmp7);
4924    Tmp6 = DAG.getNode(ISD::OR, VT, Tmp6, Tmp5);
4925    Tmp4 = DAG.getNode(ISD::OR, VT, Tmp4, Tmp3);
4926    Tmp2 = DAG.getNode(ISD::OR, VT, Tmp2, Tmp1);
4927    Tmp8 = DAG.getNode(ISD::OR, VT, Tmp8, Tmp6);
4928    Tmp4 = DAG.getNode(ISD::OR, VT, Tmp4, Tmp2);
4929    return DAG.getNode(ISD::OR, VT, Tmp8, Tmp4);
4930  }
4931}
4932
4933/// ExpandBitCount - Expand the specified bitcount instruction into operations.
4934///
4935SDOperand SelectionDAGLegalize::ExpandBitCount(unsigned Opc, SDOperand Op) {
4936  switch (Opc) {
4937  default: assert(0 && "Cannot expand this yet!");
4938  case ISD::CTPOP: {
4939    static const uint64_t mask[6] = {
4940      0x5555555555555555ULL, 0x3333333333333333ULL,
4941      0x0F0F0F0F0F0F0F0FULL, 0x00FF00FF00FF00FFULL,
4942      0x0000FFFF0000FFFFULL, 0x00000000FFFFFFFFULL
4943    };
4944    MVT::ValueType VT = Op.getValueType();
4945    MVT::ValueType ShVT = TLI.getShiftAmountTy();
4946    unsigned len = MVT::getSizeInBits(VT);
4947    for (unsigned i = 0; (1U << i) <= (len / 2); ++i) {
4948      //x = (x & mask[i][len/8]) + (x >> (1 << i) & mask[i][len/8])
4949      SDOperand Tmp2 = DAG.getConstant(mask[i], VT);
4950      SDOperand Tmp3 = DAG.getConstant(1ULL << i, ShVT);
4951      Op = DAG.getNode(ISD::ADD, VT, DAG.getNode(ISD::AND, VT, Op, Tmp2),
4952                       DAG.getNode(ISD::AND, VT,
4953                                   DAG.getNode(ISD::SRL, VT, Op, Tmp3),Tmp2));
4954    }
4955    return Op;
4956  }
4957  case ISD::CTLZ: {
4958    // for now, we do this:
4959    // x = x | (x >> 1);
4960    // x = x | (x >> 2);
4961    // ...
4962    // x = x | (x >>16);
4963    // x = x | (x >>32); // for 64-bit input
4964    // return popcount(~x);
4965    //
4966    // but see also: http://www.hackersdelight.org/HDcode/nlz.cc
4967    MVT::ValueType VT = Op.getValueType();
4968    MVT::ValueType ShVT = TLI.getShiftAmountTy();
4969    unsigned len = MVT::getSizeInBits(VT);
4970    for (unsigned i = 0; (1U << i) <= (len / 2); ++i) {
4971      SDOperand Tmp3 = DAG.getConstant(1ULL << i, ShVT);
4972      Op = DAG.getNode(ISD::OR, VT, Op, DAG.getNode(ISD::SRL, VT, Op, Tmp3));
4973    }
4974    Op = DAG.getNode(ISD::XOR, VT, Op, DAG.getConstant(~0ULL, VT));
4975    return DAG.getNode(ISD::CTPOP, VT, Op);
4976  }
4977  case ISD::CTTZ: {
4978    // for now, we use: { return popcount(~x & (x - 1)); }
4979    // unless the target has ctlz but not ctpop, in which case we use:
4980    // { return 32 - nlz(~x & (x-1)); }
4981    // see also http://www.hackersdelight.org/HDcode/ntz.cc
4982    MVT::ValueType VT = Op.getValueType();
4983    SDOperand Tmp2 = DAG.getConstant(~0ULL, VT);
4984    SDOperand Tmp3 = DAG.getNode(ISD::AND, VT,
4985                       DAG.getNode(ISD::XOR, VT, Op, Tmp2),
4986                       DAG.getNode(ISD::SUB, VT, Op, DAG.getConstant(1, VT)));
4987    // If ISD::CTLZ is legal and CTPOP isn't, then do that instead.
4988    if (!TLI.isOperationLegal(ISD::CTPOP, VT) &&
4989        TLI.isOperationLegal(ISD::CTLZ, VT))
4990      return DAG.getNode(ISD::SUB, VT,
4991                         DAG.getConstant(MVT::getSizeInBits(VT), VT),
4992                         DAG.getNode(ISD::CTLZ, VT, Tmp3));
4993    return DAG.getNode(ISD::CTPOP, VT, Tmp3);
4994  }
4995  }
4996}
4997
4998/// ExpandOp - Expand the specified SDOperand into its two component pieces
4999/// Lo&Hi.  Note that the Op MUST be an expanded type.  As a result of this, the
5000/// LegalizeNodes map is filled in for any results that are not expanded, the
5001/// ExpandedNodes map is filled in for any results that are expanded, and the
5002/// Lo/Hi values are returned.
5003void SelectionDAGLegalize::ExpandOp(SDOperand Op, SDOperand &Lo, SDOperand &Hi){
5004  MVT::ValueType VT = Op.getValueType();
5005  MVT::ValueType NVT = TLI.getTypeToTransformTo(VT);
5006  SDNode *Node = Op.Val;
5007  assert(getTypeAction(VT) == Expand && "Not an expanded type!");
5008  assert(((MVT::isInteger(NVT) && NVT < VT) || MVT::isFloatingPoint(VT) ||
5009         MVT::isVector(VT)) &&
5010         "Cannot expand to FP value or to larger int value!");
5011
5012  // See if we already expanded it.
5013  DenseMap<SDOperand, std::pair<SDOperand, SDOperand> >::iterator I
5014    = ExpandedNodes.find(Op);
5015  if (I != ExpandedNodes.end()) {
5016    Lo = I->second.first;
5017    Hi = I->second.second;
5018    return;
5019  }
5020
5021  switch (Node->getOpcode()) {
5022  case ISD::CopyFromReg:
5023    assert(0 && "CopyFromReg must be legal!");
5024  default:
5025#ifndef NDEBUG
5026    cerr << "NODE: "; Node->dump(&DAG); cerr << "\n";
5027#endif
5028    assert(0 && "Do not know how to expand this operator!");
5029    abort();
5030  case ISD::UNDEF:
5031    NVT = TLI.getTypeToExpandTo(VT);
5032    Lo = DAG.getNode(ISD::UNDEF, NVT);
5033    Hi = DAG.getNode(ISD::UNDEF, NVT);
5034    break;
5035  case ISD::Constant: {
5036    uint64_t Cst = cast<ConstantSDNode>(Node)->getValue();
5037    Lo = DAG.getConstant(Cst, NVT);
5038    Hi = DAG.getConstant(Cst >> MVT::getSizeInBits(NVT), NVT);
5039    break;
5040  }
5041  case ISD::ConstantFP: {
5042    ConstantFPSDNode *CFP = cast<ConstantFPSDNode>(Node);
5043    Lo = ExpandConstantFP(CFP, false, DAG, TLI);
5044    if (getTypeAction(Lo.getValueType()) == Expand)
5045      ExpandOp(Lo, Lo, Hi);
5046    break;
5047  }
5048  case ISD::BUILD_PAIR:
5049    // Return the operands.
5050    Lo = Node->getOperand(0);
5051    Hi = Node->getOperand(1);
5052    break;
5053
5054  case ISD::SIGN_EXTEND_INREG:
5055    ExpandOp(Node->getOperand(0), Lo, Hi);
5056    // sext_inreg the low part if needed.
5057    Lo = DAG.getNode(ISD::SIGN_EXTEND_INREG, NVT, Lo, Node->getOperand(1));
5058
5059    // The high part gets the sign extension from the lo-part.  This handles
5060    // things like sextinreg V:i64 from i8.
5061    Hi = DAG.getNode(ISD::SRA, NVT, Lo,
5062                     DAG.getConstant(MVT::getSizeInBits(NVT)-1,
5063                                     TLI.getShiftAmountTy()));
5064    break;
5065
5066  case ISD::BSWAP: {
5067    ExpandOp(Node->getOperand(0), Lo, Hi);
5068    SDOperand TempLo = DAG.getNode(ISD::BSWAP, NVT, Hi);
5069    Hi = DAG.getNode(ISD::BSWAP, NVT, Lo);
5070    Lo = TempLo;
5071    break;
5072  }
5073
5074  case ISD::CTPOP:
5075    ExpandOp(Node->getOperand(0), Lo, Hi);
5076    Lo = DAG.getNode(ISD::ADD, NVT,          // ctpop(HL) -> ctpop(H)+ctpop(L)
5077                     DAG.getNode(ISD::CTPOP, NVT, Lo),
5078                     DAG.getNode(ISD::CTPOP, NVT, Hi));
5079    Hi = DAG.getConstant(0, NVT);
5080    break;
5081
5082  case ISD::CTLZ: {
5083    // ctlz (HL) -> ctlz(H) != 32 ? ctlz(H) : (ctlz(L)+32)
5084    ExpandOp(Node->getOperand(0), Lo, Hi);
5085    SDOperand BitsC = DAG.getConstant(MVT::getSizeInBits(NVT), NVT);
5086    SDOperand HLZ = DAG.getNode(ISD::CTLZ, NVT, Hi);
5087    SDOperand TopNotZero = DAG.getSetCC(TLI.getSetCCResultTy(), HLZ, BitsC,
5088                                        ISD::SETNE);
5089    SDOperand LowPart = DAG.getNode(ISD::CTLZ, NVT, Lo);
5090    LowPart = DAG.getNode(ISD::ADD, NVT, LowPart, BitsC);
5091
5092    Lo = DAG.getNode(ISD::SELECT, NVT, TopNotZero, HLZ, LowPart);
5093    Hi = DAG.getConstant(0, NVT);
5094    break;
5095  }
5096
5097  case ISD::CTTZ: {
5098    // cttz (HL) -> cttz(L) != 32 ? cttz(L) : (cttz(H)+32)
5099    ExpandOp(Node->getOperand(0), Lo, Hi);
5100    SDOperand BitsC = DAG.getConstant(MVT::getSizeInBits(NVT), NVT);
5101    SDOperand LTZ = DAG.getNode(ISD::CTTZ, NVT, Lo);
5102    SDOperand BotNotZero = DAG.getSetCC(TLI.getSetCCResultTy(), LTZ, BitsC,
5103                                        ISD::SETNE);
5104    SDOperand HiPart = DAG.getNode(ISD::CTTZ, NVT, Hi);
5105    HiPart = DAG.getNode(ISD::ADD, NVT, HiPart, BitsC);
5106
5107    Lo = DAG.getNode(ISD::SELECT, NVT, BotNotZero, LTZ, HiPart);
5108    Hi = DAG.getConstant(0, NVT);
5109    break;
5110  }
5111
5112  case ISD::VAARG: {
5113    SDOperand Ch = Node->getOperand(0);   // Legalize the chain.
5114    SDOperand Ptr = Node->getOperand(1);  // Legalize the pointer.
5115    Lo = DAG.getVAArg(NVT, Ch, Ptr, Node->getOperand(2));
5116    Hi = DAG.getVAArg(NVT, Lo.getValue(1), Ptr, Node->getOperand(2));
5117
5118    // Remember that we legalized the chain.
5119    Hi = LegalizeOp(Hi);
5120    AddLegalizedOperand(Op.getValue(1), Hi.getValue(1));
5121    if (!TLI.isLittleEndian())
5122      std::swap(Lo, Hi);
5123    break;
5124  }
5125
5126  case ISD::LOAD: {
5127    LoadSDNode *LD = cast<LoadSDNode>(Node);
5128    SDOperand Ch  = LD->getChain();    // Legalize the chain.
5129    SDOperand Ptr = LD->getBasePtr();  // Legalize the pointer.
5130    ISD::LoadExtType ExtType = LD->getExtensionType();
5131    int SVOffset = LD->getSrcValueOffset();
5132    unsigned Alignment = LD->getAlignment();
5133    bool isVolatile = LD->isVolatile();
5134
5135    if (ExtType == ISD::NON_EXTLOAD) {
5136      Lo = DAG.getLoad(NVT, Ch, Ptr, LD->getSrcValue(), SVOffset,
5137                       isVolatile, Alignment);
5138      if (VT == MVT::f32 || VT == MVT::f64) {
5139        // f32->i32 or f64->i64 one to one expansion.
5140        // Remember that we legalized the chain.
5141        AddLegalizedOperand(SDOperand(Node, 1), LegalizeOp(Lo.getValue(1)));
5142        // Recursively expand the new load.
5143        if (getTypeAction(NVT) == Expand)
5144          ExpandOp(Lo, Lo, Hi);
5145        break;
5146      }
5147
5148      // Increment the pointer to the other half.
5149      unsigned IncrementSize = MVT::getSizeInBits(Lo.getValueType())/8;
5150      Ptr = DAG.getNode(ISD::ADD, Ptr.getValueType(), Ptr,
5151                        getIntPtrConstant(IncrementSize));
5152      SVOffset += IncrementSize;
5153      if (Alignment > IncrementSize)
5154        Alignment = IncrementSize;
5155      Hi = DAG.getLoad(NVT, Ch, Ptr, LD->getSrcValue(), SVOffset,
5156                       isVolatile, Alignment);
5157
5158      // Build a factor node to remember that this load is independent of the
5159      // other one.
5160      SDOperand TF = DAG.getNode(ISD::TokenFactor, MVT::Other, Lo.getValue(1),
5161                                 Hi.getValue(1));
5162
5163      // Remember that we legalized the chain.
5164      AddLegalizedOperand(Op.getValue(1), LegalizeOp(TF));
5165      if (!TLI.isLittleEndian())
5166        std::swap(Lo, Hi);
5167    } else {
5168      MVT::ValueType EVT = LD->getLoadedVT();
5169
5170      if (VT == MVT::f64 && EVT == MVT::f32) {
5171        // f64 = EXTLOAD f32 should expand to LOAD, FP_EXTEND
5172        SDOperand Load = DAG.getLoad(EVT, Ch, Ptr, LD->getSrcValue(),
5173                                     SVOffset, isVolatile, Alignment);
5174        // Remember that we legalized the chain.
5175        AddLegalizedOperand(SDOperand(Node, 1), LegalizeOp(Load.getValue(1)));
5176        ExpandOp(DAG.getNode(ISD::FP_EXTEND, VT, Load), Lo, Hi);
5177        break;
5178      }
5179
5180      if (EVT == NVT)
5181        Lo = DAG.getLoad(NVT, Ch, Ptr, LD->getSrcValue(),
5182                         SVOffset, isVolatile, Alignment);
5183      else
5184        Lo = DAG.getExtLoad(ExtType, NVT, Ch, Ptr, LD->getSrcValue(),
5185                            SVOffset, EVT, isVolatile,
5186                            Alignment);
5187
5188      // Remember that we legalized the chain.
5189      AddLegalizedOperand(SDOperand(Node, 1), LegalizeOp(Lo.getValue(1)));
5190
5191      if (ExtType == ISD::SEXTLOAD) {
5192        // The high part is obtained by SRA'ing all but one of the bits of the
5193        // lo part.
5194        unsigned LoSize = MVT::getSizeInBits(Lo.getValueType());
5195        Hi = DAG.getNode(ISD::SRA, NVT, Lo,
5196                         DAG.getConstant(LoSize-1, TLI.getShiftAmountTy()));
5197      } else if (ExtType == ISD::ZEXTLOAD) {
5198        // The high part is just a zero.
5199        Hi = DAG.getConstant(0, NVT);
5200      } else /* if (ExtType == ISD::EXTLOAD) */ {
5201        // The high part is undefined.
5202        Hi = DAG.getNode(ISD::UNDEF, NVT);
5203      }
5204    }
5205    break;
5206  }
5207  case ISD::AND:
5208  case ISD::OR:
5209  case ISD::XOR: {   // Simple logical operators -> two trivial pieces.
5210    SDOperand LL, LH, RL, RH;
5211    ExpandOp(Node->getOperand(0), LL, LH);
5212    ExpandOp(Node->getOperand(1), RL, RH);
5213    Lo = DAG.getNode(Node->getOpcode(), NVT, LL, RL);
5214    Hi = DAG.getNode(Node->getOpcode(), NVT, LH, RH);
5215    break;
5216  }
5217  case ISD::SELECT: {
5218    SDOperand LL, LH, RL, RH;
5219    ExpandOp(Node->getOperand(1), LL, LH);
5220    ExpandOp(Node->getOperand(2), RL, RH);
5221    if (getTypeAction(NVT) == Expand)
5222      NVT = TLI.getTypeToExpandTo(NVT);
5223    Lo = DAG.getNode(ISD::SELECT, NVT, Node->getOperand(0), LL, RL);
5224    if (VT != MVT::f32)
5225      Hi = DAG.getNode(ISD::SELECT, NVT, Node->getOperand(0), LH, RH);
5226    break;
5227  }
5228  case ISD::SELECT_CC: {
5229    SDOperand TL, TH, FL, FH;
5230    ExpandOp(Node->getOperand(2), TL, TH);
5231    ExpandOp(Node->getOperand(3), FL, FH);
5232    if (getTypeAction(NVT) == Expand)
5233      NVT = TLI.getTypeToExpandTo(NVT);
5234    Lo = DAG.getNode(ISD::SELECT_CC, NVT, Node->getOperand(0),
5235                     Node->getOperand(1), TL, FL, Node->getOperand(4));
5236    if (VT != MVT::f32)
5237      Hi = DAG.getNode(ISD::SELECT_CC, NVT, Node->getOperand(0),
5238                       Node->getOperand(1), TH, FH, Node->getOperand(4));
5239    break;
5240  }
5241  case ISD::ANY_EXTEND:
5242    // The low part is any extension of the input (which degenerates to a copy).
5243    Lo = DAG.getNode(ISD::ANY_EXTEND, NVT, Node->getOperand(0));
5244    // The high part is undefined.
5245    Hi = DAG.getNode(ISD::UNDEF, NVT);
5246    break;
5247  case ISD::SIGN_EXTEND: {
5248    // The low part is just a sign extension of the input (which degenerates to
5249    // a copy).
5250    Lo = DAG.getNode(ISD::SIGN_EXTEND, NVT, Node->getOperand(0));
5251
5252    // The high part is obtained by SRA'ing all but one of the bits of the lo
5253    // part.
5254    unsigned LoSize = MVT::getSizeInBits(Lo.getValueType());
5255    Hi = DAG.getNode(ISD::SRA, NVT, Lo,
5256                     DAG.getConstant(LoSize-1, TLI.getShiftAmountTy()));
5257    break;
5258  }
5259  case ISD::ZERO_EXTEND:
5260    // The low part is just a zero extension of the input (which degenerates to
5261    // a copy).
5262    Lo = DAG.getNode(ISD::ZERO_EXTEND, NVT, Node->getOperand(0));
5263
5264    // The high part is just a zero.
5265    Hi = DAG.getConstant(0, NVT);
5266    break;
5267
5268  case ISD::TRUNCATE: {
5269    // The input value must be larger than this value.  Expand *it*.
5270    SDOperand NewLo;
5271    ExpandOp(Node->getOperand(0), NewLo, Hi);
5272
5273    // The low part is now either the right size, or it is closer.  If not the
5274    // right size, make an illegal truncate so we recursively expand it.
5275    if (NewLo.getValueType() != Node->getValueType(0))
5276      NewLo = DAG.getNode(ISD::TRUNCATE, Node->getValueType(0), NewLo);
5277    ExpandOp(NewLo, Lo, Hi);
5278    break;
5279  }
5280
5281  case ISD::BIT_CONVERT: {
5282    SDOperand Tmp;
5283    if (TLI.getOperationAction(ISD::BIT_CONVERT, VT) == TargetLowering::Custom){
5284      // If the target wants to, allow it to lower this itself.
5285      switch (getTypeAction(Node->getOperand(0).getValueType())) {
5286      case Expand: assert(0 && "cannot expand FP!");
5287      case Legal:   Tmp = LegalizeOp(Node->getOperand(0)); break;
5288      case Promote: Tmp = PromoteOp (Node->getOperand(0)); break;
5289      }
5290      Tmp = TLI.LowerOperation(DAG.getNode(ISD::BIT_CONVERT, VT, Tmp), DAG);
5291    }
5292
5293    // f32 / f64 must be expanded to i32 / i64.
5294    if (VT == MVT::f32 || VT == MVT::f64) {
5295      Lo = DAG.getNode(ISD::BIT_CONVERT, NVT, Node->getOperand(0));
5296      if (getTypeAction(NVT) == Expand)
5297        ExpandOp(Lo, Lo, Hi);
5298      break;
5299    }
5300
5301    // If source operand will be expanded to the same type as VT, i.e.
5302    // i64 <- f64, i32 <- f32, expand the source operand instead.
5303    MVT::ValueType VT0 = Node->getOperand(0).getValueType();
5304    if (getTypeAction(VT0) == Expand && TLI.getTypeToTransformTo(VT0) == VT) {
5305      ExpandOp(Node->getOperand(0), Lo, Hi);
5306      break;
5307    }
5308
5309    // Turn this into a load/store pair by default.
5310    if (Tmp.Val == 0)
5311      Tmp = ExpandBIT_CONVERT(VT, Node->getOperand(0));
5312
5313    ExpandOp(Tmp, Lo, Hi);
5314    break;
5315  }
5316
5317  case ISD::READCYCLECOUNTER:
5318    assert(TLI.getOperationAction(ISD::READCYCLECOUNTER, VT) ==
5319                 TargetLowering::Custom &&
5320           "Must custom expand ReadCycleCounter");
5321    Lo = TLI.LowerOperation(Op, DAG);
5322    assert(Lo.Val && "Node must be custom expanded!");
5323    Hi = Lo.getValue(1);
5324    AddLegalizedOperand(SDOperand(Node, 1), // Remember we legalized the chain.
5325                        LegalizeOp(Lo.getValue(2)));
5326    break;
5327
5328    // These operators cannot be expanded directly, emit them as calls to
5329    // library functions.
5330  case ISD::FP_TO_SINT: {
5331    if (TLI.getOperationAction(ISD::FP_TO_SINT, VT) == TargetLowering::Custom) {
5332      SDOperand Op;
5333      switch (getTypeAction(Node->getOperand(0).getValueType())) {
5334      case Expand: assert(0 && "cannot expand FP!");
5335      case Legal:   Op = LegalizeOp(Node->getOperand(0)); break;
5336      case Promote: Op = PromoteOp (Node->getOperand(0)); break;
5337      }
5338
5339      Op = TLI.LowerOperation(DAG.getNode(ISD::FP_TO_SINT, VT, Op), DAG);
5340
5341      // Now that the custom expander is done, expand the result, which is still
5342      // VT.
5343      if (Op.Val) {
5344        ExpandOp(Op, Lo, Hi);
5345        break;
5346      }
5347    }
5348
5349    RTLIB::Libcall LC;
5350    if (Node->getOperand(0).getValueType() == MVT::f32)
5351      LC = RTLIB::FPTOSINT_F32_I64;
5352    else
5353      LC = RTLIB::FPTOSINT_F64_I64;
5354    Lo = ExpandLibCall(TLI.getLibcallName(LC), Node,
5355                       false/*sign irrelevant*/, Hi);
5356    break;
5357  }
5358
5359  case ISD::FP_TO_UINT: {
5360    if (TLI.getOperationAction(ISD::FP_TO_UINT, VT) == TargetLowering::Custom) {
5361      SDOperand Op;
5362      switch (getTypeAction(Node->getOperand(0).getValueType())) {
5363        case Expand: assert(0 && "cannot expand FP!");
5364        case Legal:   Op = LegalizeOp(Node->getOperand(0)); break;
5365        case Promote: Op = PromoteOp (Node->getOperand(0)); break;
5366      }
5367
5368      Op = TLI.LowerOperation(DAG.getNode(ISD::FP_TO_UINT, VT, Op), DAG);
5369
5370      // Now that the custom expander is done, expand the result.
5371      if (Op.Val) {
5372        ExpandOp(Op, Lo, Hi);
5373        break;
5374      }
5375    }
5376
5377    RTLIB::Libcall LC;
5378    if (Node->getOperand(0).getValueType() == MVT::f32)
5379      LC = RTLIB::FPTOUINT_F32_I64;
5380    else
5381      LC = RTLIB::FPTOUINT_F64_I64;
5382    Lo = ExpandLibCall(TLI.getLibcallName(LC), Node,
5383                       false/*sign irrelevant*/, Hi);
5384    break;
5385  }
5386
5387  case ISD::SHL: {
5388    // If the target wants custom lowering, do so.
5389    SDOperand ShiftAmt = LegalizeOp(Node->getOperand(1));
5390    if (TLI.getOperationAction(ISD::SHL, VT) == TargetLowering::Custom) {
5391      SDOperand Op = DAG.getNode(ISD::SHL, VT, Node->getOperand(0), ShiftAmt);
5392      Op = TLI.LowerOperation(Op, DAG);
5393      if (Op.Val) {
5394        // Now that the custom expander is done, expand the result, which is
5395        // still VT.
5396        ExpandOp(Op, Lo, Hi);
5397        break;
5398      }
5399    }
5400
5401    // If ADDC/ADDE are supported and if the shift amount is a constant 1, emit
5402    // this X << 1 as X+X.
5403    if (ConstantSDNode *ShAmt = dyn_cast<ConstantSDNode>(ShiftAmt)) {
5404      if (ShAmt->getValue() == 1 && TLI.isOperationLegal(ISD::ADDC, NVT) &&
5405          TLI.isOperationLegal(ISD::ADDE, NVT)) {
5406        SDOperand LoOps[2], HiOps[3];
5407        ExpandOp(Node->getOperand(0), LoOps[0], HiOps[0]);
5408        SDVTList VTList = DAG.getVTList(LoOps[0].getValueType(), MVT::Flag);
5409        LoOps[1] = LoOps[0];
5410        Lo = DAG.getNode(ISD::ADDC, VTList, LoOps, 2);
5411
5412        HiOps[1] = HiOps[0];
5413        HiOps[2] = Lo.getValue(1);
5414        Hi = DAG.getNode(ISD::ADDE, VTList, HiOps, 3);
5415        break;
5416      }
5417    }
5418
5419    // If we can emit an efficient shift operation, do so now.
5420    if (ExpandShift(ISD::SHL, Node->getOperand(0), ShiftAmt, Lo, Hi))
5421      break;
5422
5423    // If this target supports SHL_PARTS, use it.
5424    TargetLowering::LegalizeAction Action =
5425      TLI.getOperationAction(ISD::SHL_PARTS, NVT);
5426    if ((Action == TargetLowering::Legal && TLI.isTypeLegal(NVT)) ||
5427        Action == TargetLowering::Custom) {
5428      ExpandShiftParts(ISD::SHL_PARTS, Node->getOperand(0), ShiftAmt, Lo, Hi);
5429      break;
5430    }
5431
5432    // Otherwise, emit a libcall.
5433    Lo = ExpandLibCall(TLI.getLibcallName(RTLIB::SHL_I64), Node,
5434                       false/*left shift=unsigned*/, Hi);
5435    break;
5436  }
5437
5438  case ISD::SRA: {
5439    // If the target wants custom lowering, do so.
5440    SDOperand ShiftAmt = LegalizeOp(Node->getOperand(1));
5441    if (TLI.getOperationAction(ISD::SRA, VT) == TargetLowering::Custom) {
5442      SDOperand Op = DAG.getNode(ISD::SRA, VT, Node->getOperand(0), ShiftAmt);
5443      Op = TLI.LowerOperation(Op, DAG);
5444      if (Op.Val) {
5445        // Now that the custom expander is done, expand the result, which is
5446        // still VT.
5447        ExpandOp(Op, Lo, Hi);
5448        break;
5449      }
5450    }
5451
5452    // If we can emit an efficient shift operation, do so now.
5453    if (ExpandShift(ISD::SRA, Node->getOperand(0), ShiftAmt, Lo, Hi))
5454      break;
5455
5456    // If this target supports SRA_PARTS, use it.
5457    TargetLowering::LegalizeAction Action =
5458      TLI.getOperationAction(ISD::SRA_PARTS, NVT);
5459    if ((Action == TargetLowering::Legal && TLI.isTypeLegal(NVT)) ||
5460        Action == TargetLowering::Custom) {
5461      ExpandShiftParts(ISD::SRA_PARTS, Node->getOperand(0), ShiftAmt, Lo, Hi);
5462      break;
5463    }
5464
5465    // Otherwise, emit a libcall.
5466    Lo = ExpandLibCall(TLI.getLibcallName(RTLIB::SRA_I64), Node,
5467                       true/*ashr is signed*/, Hi);
5468    break;
5469  }
5470
5471  case ISD::SRL: {
5472    // If the target wants custom lowering, do so.
5473    SDOperand ShiftAmt = LegalizeOp(Node->getOperand(1));
5474    if (TLI.getOperationAction(ISD::SRL, VT) == TargetLowering::Custom) {
5475      SDOperand Op = DAG.getNode(ISD::SRL, VT, Node->getOperand(0), ShiftAmt);
5476      Op = TLI.LowerOperation(Op, DAG);
5477      if (Op.Val) {
5478        // Now that the custom expander is done, expand the result, which is
5479        // still VT.
5480        ExpandOp(Op, Lo, Hi);
5481        break;
5482      }
5483    }
5484
5485    // If we can emit an efficient shift operation, do so now.
5486    if (ExpandShift(ISD::SRL, Node->getOperand(0), ShiftAmt, Lo, Hi))
5487      break;
5488
5489    // If this target supports SRL_PARTS, use it.
5490    TargetLowering::LegalizeAction Action =
5491      TLI.getOperationAction(ISD::SRL_PARTS, NVT);
5492    if ((Action == TargetLowering::Legal && TLI.isTypeLegal(NVT)) ||
5493        Action == TargetLowering::Custom) {
5494      ExpandShiftParts(ISD::SRL_PARTS, Node->getOperand(0), ShiftAmt, Lo, Hi);
5495      break;
5496    }
5497
5498    // Otherwise, emit a libcall.
5499    Lo = ExpandLibCall(TLI.getLibcallName(RTLIB::SRL_I64), Node,
5500                       false/*lshr is unsigned*/, Hi);
5501    break;
5502  }
5503
5504  case ISD::ADD:
5505  case ISD::SUB: {
5506    // If the target wants to custom expand this, let them.
5507    if (TLI.getOperationAction(Node->getOpcode(), VT) ==
5508            TargetLowering::Custom) {
5509      Op = TLI.LowerOperation(Op, DAG);
5510      if (Op.Val) {
5511        ExpandOp(Op, Lo, Hi);
5512        break;
5513      }
5514    }
5515
5516    // Expand the subcomponents.
5517    SDOperand LHSL, LHSH, RHSL, RHSH;
5518    ExpandOp(Node->getOperand(0), LHSL, LHSH);
5519    ExpandOp(Node->getOperand(1), RHSL, RHSH);
5520    SDVTList VTList = DAG.getVTList(LHSL.getValueType(), MVT::Flag);
5521    SDOperand LoOps[2], HiOps[3];
5522    LoOps[0] = LHSL;
5523    LoOps[1] = RHSL;
5524    HiOps[0] = LHSH;
5525    HiOps[1] = RHSH;
5526    if (Node->getOpcode() == ISD::ADD) {
5527      Lo = DAG.getNode(ISD::ADDC, VTList, LoOps, 2);
5528      HiOps[2] = Lo.getValue(1);
5529      Hi = DAG.getNode(ISD::ADDE, VTList, HiOps, 3);
5530    } else {
5531      Lo = DAG.getNode(ISD::SUBC, VTList, LoOps, 2);
5532      HiOps[2] = Lo.getValue(1);
5533      Hi = DAG.getNode(ISD::SUBE, VTList, HiOps, 3);
5534    }
5535    break;
5536  }
5537
5538  case ISD::ADDC:
5539  case ISD::SUBC: {
5540    // Expand the subcomponents.
5541    SDOperand LHSL, LHSH, RHSL, RHSH;
5542    ExpandOp(Node->getOperand(0), LHSL, LHSH);
5543    ExpandOp(Node->getOperand(1), RHSL, RHSH);
5544    SDVTList VTList = DAG.getVTList(LHSL.getValueType(), MVT::Flag);
5545    SDOperand LoOps[2] = { LHSL, RHSL };
5546    SDOperand HiOps[3] = { LHSH, RHSH };
5547
5548    if (Node->getOpcode() == ISD::ADDC) {
5549      Lo = DAG.getNode(ISD::ADDC, VTList, LoOps, 2);
5550      HiOps[2] = Lo.getValue(1);
5551      Hi = DAG.getNode(ISD::ADDE, VTList, HiOps, 3);
5552    } else {
5553      Lo = DAG.getNode(ISD::SUBC, VTList, LoOps, 2);
5554      HiOps[2] = Lo.getValue(1);
5555      Hi = DAG.getNode(ISD::SUBE, VTList, HiOps, 3);
5556    }
5557    // Remember that we legalized the flag.
5558    AddLegalizedOperand(Op.getValue(1), LegalizeOp(Hi.getValue(1)));
5559    break;
5560  }
5561  case ISD::ADDE:
5562  case ISD::SUBE: {
5563    // Expand the subcomponents.
5564    SDOperand LHSL, LHSH, RHSL, RHSH;
5565    ExpandOp(Node->getOperand(0), LHSL, LHSH);
5566    ExpandOp(Node->getOperand(1), RHSL, RHSH);
5567    SDVTList VTList = DAG.getVTList(LHSL.getValueType(), MVT::Flag);
5568    SDOperand LoOps[3] = { LHSL, RHSL, Node->getOperand(2) };
5569    SDOperand HiOps[3] = { LHSH, RHSH };
5570
5571    Lo = DAG.getNode(Node->getOpcode(), VTList, LoOps, 3);
5572    HiOps[2] = Lo.getValue(1);
5573    Hi = DAG.getNode(Node->getOpcode(), VTList, HiOps, 3);
5574
5575    // Remember that we legalized the flag.
5576    AddLegalizedOperand(Op.getValue(1), LegalizeOp(Hi.getValue(1)));
5577    break;
5578  }
5579  case ISD::MUL: {
5580    // If the target wants to custom expand this, let them.
5581    if (TLI.getOperationAction(ISD::MUL, VT) == TargetLowering::Custom) {
5582      SDOperand New = TLI.LowerOperation(Op, DAG);
5583      if (New.Val) {
5584        ExpandOp(New, Lo, Hi);
5585        break;
5586      }
5587    }
5588
5589    bool HasMULHS = TLI.isOperationLegal(ISD::MULHS, NVT);
5590    bool HasMULHU = TLI.isOperationLegal(ISD::MULHU, NVT);
5591    if (HasMULHS || HasMULHU) {
5592      SDOperand LL, LH, RL, RH;
5593      ExpandOp(Node->getOperand(0), LL, LH);
5594      ExpandOp(Node->getOperand(1), RL, RH);
5595      unsigned SH = MVT::getSizeInBits(RH.getValueType())-1;
5596      // FIXME: Move this to the dag combiner.
5597      // MULHS implicitly sign extends its inputs.  Check to see if ExpandOp
5598      // extended the sign bit of the low half through the upper half, and if so
5599      // emit a MULHS instead of the alternate sequence that is valid for any
5600      // i64 x i64 multiply.
5601      if (HasMULHS &&
5602          // is RH an extension of the sign bit of RL?
5603          RH.getOpcode() == ISD::SRA && RH.getOperand(0) == RL &&
5604          RH.getOperand(1).getOpcode() == ISD::Constant &&
5605          cast<ConstantSDNode>(RH.getOperand(1))->getValue() == SH &&
5606          // is LH an extension of the sign bit of LL?
5607          LH.getOpcode() == ISD::SRA && LH.getOperand(0) == LL &&
5608          LH.getOperand(1).getOpcode() == ISD::Constant &&
5609          cast<ConstantSDNode>(LH.getOperand(1))->getValue() == SH) {
5610        // Low part:
5611        Lo = DAG.getNode(ISD::MUL, NVT, LL, RL);
5612        // High part:
5613        Hi = DAG.getNode(ISD::MULHS, NVT, LL, RL);
5614        break;
5615      } else if (HasMULHU) {
5616        // Low part:
5617        Lo = DAG.getNode(ISD::MUL, NVT, LL, RL);
5618
5619        // High part:
5620        Hi = DAG.getNode(ISD::MULHU, NVT, LL, RL);
5621        RH = DAG.getNode(ISD::MUL, NVT, LL, RH);
5622        LH = DAG.getNode(ISD::MUL, NVT, LH, RL);
5623        Hi = DAG.getNode(ISD::ADD, NVT, Hi, RH);
5624        Hi = DAG.getNode(ISD::ADD, NVT, Hi, LH);
5625        break;
5626      }
5627    }
5628
5629    Lo = ExpandLibCall(TLI.getLibcallName(RTLIB::MUL_I64), Node,
5630                       false/*sign irrelevant*/, Hi);
5631    break;
5632  }
5633  case ISD::SDIV:
5634    Lo = ExpandLibCall(TLI.getLibcallName(RTLIB::SDIV_I64), Node, true, Hi);
5635    break;
5636  case ISD::UDIV:
5637    Lo = ExpandLibCall(TLI.getLibcallName(RTLIB::UDIV_I64), Node, true, Hi);
5638    break;
5639  case ISD::SREM:
5640    Lo = ExpandLibCall(TLI.getLibcallName(RTLIB::SREM_I64), Node, true, Hi);
5641    break;
5642  case ISD::UREM:
5643    Lo = ExpandLibCall(TLI.getLibcallName(RTLIB::UREM_I64), Node, true, Hi);
5644    break;
5645
5646  case ISD::FADD:
5647    Lo = ExpandLibCall(TLI.getLibcallName((VT == MVT::f32)
5648                                          ? RTLIB::ADD_F32 : RTLIB::ADD_F64),
5649                       Node, false, Hi);
5650    break;
5651  case ISD::FSUB:
5652    Lo = ExpandLibCall(TLI.getLibcallName((VT == MVT::f32)
5653                                          ? RTLIB::SUB_F32 : RTLIB::SUB_F64),
5654                       Node, false, Hi);
5655    break;
5656  case ISD::FMUL:
5657    Lo = ExpandLibCall(TLI.getLibcallName((VT == MVT::f32)
5658                                          ? RTLIB::MUL_F32 : RTLIB::MUL_F64),
5659                       Node, false, Hi);
5660    break;
5661  case ISD::FDIV:
5662    Lo = ExpandLibCall(TLI.getLibcallName((VT == MVT::f32)
5663                                          ? RTLIB::DIV_F32 : RTLIB::DIV_F64),
5664                       Node, false, Hi);
5665    break;
5666  case ISD::FP_EXTEND:
5667    Lo = ExpandLibCall(TLI.getLibcallName(RTLIB::FPEXT_F32_F64), Node, true,Hi);
5668    break;
5669  case ISD::FP_ROUND:
5670    Lo = ExpandLibCall(TLI.getLibcallName(RTLIB::FPROUND_F64_F32),Node,true,Hi);
5671    break;
5672  case ISD::FPOWI:
5673    Lo = ExpandLibCall(TLI.getLibcallName((VT == MVT::f32)
5674                                          ? RTLIB::POWI_F32 : RTLIB::POWI_F64),
5675                       Node, false, Hi);
5676    break;
5677  case ISD::FSQRT:
5678  case ISD::FSIN:
5679  case ISD::FCOS: {
5680    RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
5681    switch(Node->getOpcode()) {
5682    case ISD::FSQRT:
5683      LC = (VT == MVT::f32) ? RTLIB::SQRT_F32 : RTLIB::SQRT_F64;
5684      break;
5685    case ISD::FSIN:
5686      LC = (VT == MVT::f32) ? RTLIB::SIN_F32 : RTLIB::SIN_F64;
5687      break;
5688    case ISD::FCOS:
5689      LC = (VT == MVT::f32) ? RTLIB::COS_F32 : RTLIB::COS_F64;
5690      break;
5691    default: assert(0 && "Unreachable!");
5692    }
5693    Lo = ExpandLibCall(TLI.getLibcallName(LC), Node, false, Hi);
5694    break;
5695  }
5696  case ISD::FABS: {
5697    SDOperand Mask = (VT == MVT::f64)
5698      ? DAG.getConstantFP(BitsToDouble(~(1ULL << 63)), VT)
5699      : DAG.getConstantFP(BitsToFloat(~(1U << 31)), VT);
5700    Mask = DAG.getNode(ISD::BIT_CONVERT, NVT, Mask);
5701    Lo = DAG.getNode(ISD::BIT_CONVERT, NVT, Node->getOperand(0));
5702    Lo = DAG.getNode(ISD::AND, NVT, Lo, Mask);
5703    if (getTypeAction(NVT) == Expand)
5704      ExpandOp(Lo, Lo, Hi);
5705    break;
5706  }
5707  case ISD::FNEG: {
5708    SDOperand Mask = (VT == MVT::f64)
5709      ? DAG.getConstantFP(BitsToDouble(1ULL << 63), VT)
5710      : DAG.getConstantFP(BitsToFloat(1U << 31), VT);
5711    Mask = DAG.getNode(ISD::BIT_CONVERT, NVT, Mask);
5712    Lo = DAG.getNode(ISD::BIT_CONVERT, NVT, Node->getOperand(0));
5713    Lo = DAG.getNode(ISD::XOR, NVT, Lo, Mask);
5714    if (getTypeAction(NVT) == Expand)
5715      ExpandOp(Lo, Lo, Hi);
5716    break;
5717  }
5718  case ISD::FCOPYSIGN: {
5719    Lo = ExpandFCOPYSIGNToBitwiseOps(Node, NVT, DAG, TLI);
5720    if (getTypeAction(NVT) == Expand)
5721      ExpandOp(Lo, Lo, Hi);
5722    break;
5723  }
5724  case ISD::SINT_TO_FP:
5725  case ISD::UINT_TO_FP: {
5726    bool isSigned = Node->getOpcode() == ISD::SINT_TO_FP;
5727    MVT::ValueType SrcVT = Node->getOperand(0).getValueType();
5728    RTLIB::Libcall LC;
5729    if (Node->getOperand(0).getValueType() == MVT::i64) {
5730      if (VT == MVT::f32)
5731        LC = isSigned ? RTLIB::SINTTOFP_I64_F32 : RTLIB::UINTTOFP_I64_F32;
5732      else
5733        LC = isSigned ? RTLIB::SINTTOFP_I64_F64 : RTLIB::UINTTOFP_I64_F64;
5734    } else {
5735      if (VT == MVT::f32)
5736        LC = isSigned ? RTLIB::SINTTOFP_I32_F32 : RTLIB::UINTTOFP_I32_F32;
5737      else
5738        LC = isSigned ? RTLIB::SINTTOFP_I32_F64 : RTLIB::UINTTOFP_I32_F64;
5739    }
5740
5741    // Promote the operand if needed.
5742    if (getTypeAction(SrcVT) == Promote) {
5743      SDOperand Tmp = PromoteOp(Node->getOperand(0));
5744      Tmp = isSigned
5745        ? DAG.getNode(ISD::SIGN_EXTEND_INREG, Tmp.getValueType(), Tmp,
5746                      DAG.getValueType(SrcVT))
5747        : DAG.getZeroExtendInReg(Tmp, SrcVT);
5748      Node = DAG.UpdateNodeOperands(Op, Tmp).Val;
5749    }
5750
5751    const char *LibCall = TLI.getLibcallName(LC);
5752    if (LibCall)
5753      Lo = ExpandLibCall(TLI.getLibcallName(LC), Node, isSigned, Hi);
5754    else  {
5755      Lo = ExpandIntToFP(Node->getOpcode() == ISD::SINT_TO_FP, VT,
5756                         Node->getOperand(0));
5757      if (getTypeAction(Lo.getValueType()) == Expand)
5758        ExpandOp(Lo, Lo, Hi);
5759    }
5760    break;
5761  }
5762  }
5763
5764  // Make sure the resultant values have been legalized themselves, unless this
5765  // is a type that requires multi-step expansion.
5766  if (getTypeAction(NVT) != Expand && NVT != MVT::isVoid) {
5767    Lo = LegalizeOp(Lo);
5768    if (Hi.Val)
5769      // Don't legalize the high part if it is expanded to a single node.
5770      Hi = LegalizeOp(Hi);
5771  }
5772
5773  // Remember in a map if the values will be reused later.
5774  bool isNew = ExpandedNodes.insert(std::make_pair(Op, std::make_pair(Lo, Hi)));
5775  assert(isNew && "Value already expanded?!?");
5776}
5777
5778/// SplitVectorOp - Given an operand of vector type, break it down into
5779/// two smaller values, still of vector type.
5780void SelectionDAGLegalize::SplitVectorOp(SDOperand Op, SDOperand &Lo,
5781                                         SDOperand &Hi) {
5782  assert(MVT::isVector(Op.getValueType()) && "Cannot split non-vector type!");
5783  SDNode *Node = Op.Val;
5784  unsigned NumElements = MVT::getVectorNumElements(Node->getValueType(0));
5785  assert(NumElements > 1 && "Cannot split a single element vector!");
5786  unsigned NewNumElts = NumElements/2;
5787  MVT::ValueType NewEltVT = MVT::getVectorElementType(Node->getValueType(0));
5788  MVT::ValueType NewVT = MVT::getVectorType(NewEltVT, NewNumElts);
5789
5790  // See if we already split it.
5791  std::map<SDOperand, std::pair<SDOperand, SDOperand> >::iterator I
5792    = SplitNodes.find(Op);
5793  if (I != SplitNodes.end()) {
5794    Lo = I->second.first;
5795    Hi = I->second.second;
5796    return;
5797  }
5798
5799  switch (Node->getOpcode()) {
5800  default:
5801#ifndef NDEBUG
5802    Node->dump(&DAG);
5803#endif
5804    assert(0 && "Unhandled operation in SplitVectorOp!");
5805  case ISD::BUILD_PAIR:
5806    Lo = Node->getOperand(0);
5807    Hi = Node->getOperand(1);
5808    break;
5809  case ISD::BUILD_VECTOR: {
5810    SmallVector<SDOperand, 8> LoOps(Node->op_begin(),
5811                                    Node->op_begin()+NewNumElts);
5812    Lo = DAG.getNode(ISD::BUILD_VECTOR, NewVT, &LoOps[0], LoOps.size());
5813
5814    SmallVector<SDOperand, 8> HiOps(Node->op_begin()+NewNumElts,
5815                                    Node->op_end());
5816    Hi = DAG.getNode(ISD::BUILD_VECTOR, NewVT, &HiOps[0], HiOps.size());
5817    break;
5818  }
5819  case ISD::CONCAT_VECTORS: {
5820    unsigned NewNumSubvectors = Node->getNumOperands() / 2;
5821    if (NewNumSubvectors == 1) {
5822      Lo = Node->getOperand(0);
5823      Hi = Node->getOperand(1);
5824    } else {
5825      SmallVector<SDOperand, 8> LoOps(Node->op_begin(),
5826                                      Node->op_begin()+NewNumSubvectors);
5827      Lo = DAG.getNode(ISD::CONCAT_VECTORS, NewVT, &LoOps[0], LoOps.size());
5828
5829      SmallVector<SDOperand, 8> HiOps(Node->op_begin()+NewNumSubvectors,
5830                                      Node->op_end());
5831      Hi = DAG.getNode(ISD::CONCAT_VECTORS, NewVT, &HiOps[0], HiOps.size());
5832    }
5833    break;
5834  }
5835  case ISD::ADD:
5836  case ISD::SUB:
5837  case ISD::MUL:
5838  case ISD::FADD:
5839  case ISD::FSUB:
5840  case ISD::FMUL:
5841  case ISD::SDIV:
5842  case ISD::UDIV:
5843  case ISD::FDIV:
5844  case ISD::AND:
5845  case ISD::OR:
5846  case ISD::XOR: {
5847    SDOperand LL, LH, RL, RH;
5848    SplitVectorOp(Node->getOperand(0), LL, LH);
5849    SplitVectorOp(Node->getOperand(1), RL, RH);
5850
5851    Lo = DAG.getNode(Node->getOpcode(), NewVT, LL, RL);
5852    Hi = DAG.getNode(Node->getOpcode(), NewVT, LH, RH);
5853    break;
5854  }
5855  case ISD::LOAD: {
5856    LoadSDNode *LD = cast<LoadSDNode>(Node);
5857    SDOperand Ch = LD->getChain();
5858    SDOperand Ptr = LD->getBasePtr();
5859    const Value *SV = LD->getSrcValue();
5860    int SVOffset = LD->getSrcValueOffset();
5861    unsigned Alignment = LD->getAlignment();
5862    bool isVolatile = LD->isVolatile();
5863
5864    Lo = DAG.getLoad(NewVT, Ch, Ptr, SV, SVOffset, isVolatile, Alignment);
5865    unsigned IncrementSize = NewNumElts * MVT::getSizeInBits(NewEltVT)/8;
5866    Ptr = DAG.getNode(ISD::ADD, Ptr.getValueType(), Ptr,
5867                      getIntPtrConstant(IncrementSize));
5868    SVOffset += IncrementSize;
5869    if (Alignment > IncrementSize)
5870      Alignment = IncrementSize;
5871    Hi = DAG.getLoad(NewVT, Ch, Ptr, SV, SVOffset, isVolatile, Alignment);
5872
5873    // Build a factor node to remember that this load is independent of the
5874    // other one.
5875    SDOperand TF = DAG.getNode(ISD::TokenFactor, MVT::Other, Lo.getValue(1),
5876                               Hi.getValue(1));
5877
5878    // Remember that we legalized the chain.
5879    AddLegalizedOperand(Op.getValue(1), LegalizeOp(TF));
5880    break;
5881  }
5882  case ISD::BIT_CONVERT: {
5883    // We know the result is a vector.  The input may be either a vector or a
5884    // scalar value.
5885    SDOperand InOp = Node->getOperand(0);
5886    if (!MVT::isVector(InOp.getValueType()) ||
5887        MVT::getVectorNumElements(InOp.getValueType()) == 1) {
5888      // The input is a scalar or single-element vector.
5889      // Lower to a store/load so that it can be split.
5890      // FIXME: this could be improved probably.
5891      SDOperand Ptr = CreateStackTemporary(InOp.getValueType());
5892
5893      SDOperand St = DAG.getStore(DAG.getEntryNode(),
5894                                  InOp, Ptr, NULL, 0);
5895      InOp = DAG.getLoad(Op.getValueType(), St, Ptr, NULL, 0);
5896    }
5897    // Split the vector and convert each of the pieces now.
5898    SplitVectorOp(InOp, Lo, Hi);
5899    Lo = DAG.getNode(ISD::BIT_CONVERT, NewVT, Lo);
5900    Hi = DAG.getNode(ISD::BIT_CONVERT, NewVT, Hi);
5901    break;
5902  }
5903  }
5904
5905  // Remember in a map if the values will be reused later.
5906  bool isNew =
5907    SplitNodes.insert(std::make_pair(Op, std::make_pair(Lo, Hi))).second;
5908  assert(isNew && "Value already split?!?");
5909}
5910
5911
5912/// ScalarizeVectorOp - Given an operand of single-element vector type
5913/// (e.g. v1f32), convert it into the equivalent operation that returns a
5914/// scalar (e.g. f32) value.
5915SDOperand SelectionDAGLegalize::ScalarizeVectorOp(SDOperand Op) {
5916  assert(MVT::isVector(Op.getValueType()) &&
5917         "Bad ScalarizeVectorOp invocation!");
5918  SDNode *Node = Op.Val;
5919  MVT::ValueType NewVT = MVT::getVectorElementType(Op.getValueType());
5920  assert(MVT::getVectorNumElements(Op.getValueType()) == 1);
5921
5922  // See if we already scalarized it.
5923  std::map<SDOperand, SDOperand>::iterator I = ScalarizedNodes.find(Op);
5924  if (I != ScalarizedNodes.end()) return I->second;
5925
5926  SDOperand Result;
5927  switch (Node->getOpcode()) {
5928  default:
5929#ifndef NDEBUG
5930    Node->dump(&DAG); cerr << "\n";
5931#endif
5932    assert(0 && "Unknown vector operation in ScalarizeVectorOp!");
5933  case ISD::ADD:
5934  case ISD::FADD:
5935  case ISD::SUB:
5936  case ISD::FSUB:
5937  case ISD::MUL:
5938  case ISD::FMUL:
5939  case ISD::SDIV:
5940  case ISD::UDIV:
5941  case ISD::FDIV:
5942  case ISD::SREM:
5943  case ISD::UREM:
5944  case ISD::FREM:
5945  case ISD::AND:
5946  case ISD::OR:
5947  case ISD::XOR:
5948    Result = DAG.getNode(Node->getOpcode(),
5949                         NewVT,
5950                         ScalarizeVectorOp(Node->getOperand(0)),
5951                         ScalarizeVectorOp(Node->getOperand(1)));
5952    break;
5953  case ISD::FNEG:
5954  case ISD::FABS:
5955  case ISD::FSQRT:
5956  case ISD::FSIN:
5957  case ISD::FCOS:
5958    Result = DAG.getNode(Node->getOpcode(),
5959                         NewVT,
5960                         ScalarizeVectorOp(Node->getOperand(0)));
5961    break;
5962  case ISD::LOAD: {
5963    LoadSDNode *LD = cast<LoadSDNode>(Node);
5964    SDOperand Ch = LegalizeOp(LD->getChain());     // Legalize the chain.
5965    SDOperand Ptr = LegalizeOp(LD->getBasePtr());  // Legalize the pointer.
5966
5967    const Value *SV = LD->getSrcValue();
5968    int SVOffset = LD->getSrcValueOffset();
5969    Result = DAG.getLoad(NewVT, Ch, Ptr, SV, SVOffset,
5970                         LD->isVolatile(), LD->getAlignment());
5971
5972    // Remember that we legalized the chain.
5973    AddLegalizedOperand(Op.getValue(1), LegalizeOp(Result.getValue(1)));
5974    break;
5975  }
5976  case ISD::BUILD_VECTOR:
5977    Result = Node->getOperand(0);
5978    break;
5979  case ISD::INSERT_VECTOR_ELT:
5980    // Returning the inserted scalar element.
5981    Result = Node->getOperand(1);
5982    break;
5983  case ISD::CONCAT_VECTORS:
5984    assert(Node->getOperand(0).getValueType() == NewVT &&
5985           "Concat of non-legal vectors not yet supported!");
5986    Result = Node->getOperand(0);
5987    break;
5988  case ISD::VECTOR_SHUFFLE: {
5989    // Figure out if the scalar is the LHS or RHS and return it.
5990    SDOperand EltNum = Node->getOperand(2).getOperand(0);
5991    if (cast<ConstantSDNode>(EltNum)->getValue())
5992      Result = ScalarizeVectorOp(Node->getOperand(1));
5993    else
5994      Result = ScalarizeVectorOp(Node->getOperand(0));
5995    break;
5996  }
5997  case ISD::EXTRACT_SUBVECTOR:
5998    Result = Node->getOperand(0);
5999    assert(Result.getValueType() == NewVT);
6000    break;
6001  case ISD::BIT_CONVERT:
6002    Result = DAG.getNode(ISD::BIT_CONVERT, NewVT, Op.getOperand(0));
6003    break;
6004  case ISD::SELECT:
6005    Result = DAG.getNode(ISD::SELECT, NewVT, Op.getOperand(0),
6006                         ScalarizeVectorOp(Op.getOperand(1)),
6007                         ScalarizeVectorOp(Op.getOperand(2)));
6008    break;
6009  }
6010
6011  if (TLI.isTypeLegal(NewVT))
6012    Result = LegalizeOp(Result);
6013  bool isNew = ScalarizedNodes.insert(std::make_pair(Op, Result)).second;
6014  assert(isNew && "Value already scalarized?");
6015  return Result;
6016}
6017
6018
6019// SelectionDAG::Legalize - This is the entry point for the file.
6020//
6021void SelectionDAG::Legalize() {
6022  if (ViewLegalizeDAGs) viewGraph();
6023
6024  /// run - This is the main entry point to this class.
6025  ///
6026  SelectionDAGLegalize(*this).LegalizeDAG();
6027}
6028
6029