SelectionDAG.h revision 002d83418a7be0083752fa910a6187e65124c78e 
1//===-- llvm/CodeGen/SelectionDAG.h - InstSelection DAG ---------*- C++ -*-===//
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 declares the SelectionDAG class, and transitively defines the
11// SDNode class and subclasses.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_CODEGEN_SELECTIONDAG_H
16#define LLVM_CODEGEN_SELECTIONDAG_H
17
18#include "llvm/CodeGen/SelectionDAGNodes.h"
19#include "llvm/ADT/ilist"
20
21#include <map>
22#include <list>
23#include <string>
24
25namespace llvm {
26  class TargetLowering;
27  class TargetMachine;
28  class MachineFunction;
29
30/// SelectionDAG class - This is used to represent a portion of an LLVM function
31/// in a low-level Data Dependence DAG representation suitable for instruction
32/// selection.  This DAG is constructed as the first step of instruction
33/// selection in order to allow implementation of machine specific optimizations
34/// and code simplifications.
35///
36/// The representation used by the SelectionDAG is a target-independent
37/// representation, which has some similarities to the GCC RTL representation,
38/// but is significantly more simple, powerful, and is a graph form instead of a
39/// linear form.
40///
41class SelectionDAG {
42  TargetLowering &TLI;
43  MachineFunction &MF;
44
45  // Root - The root of the entire DAG.  EntryNode - The starting token.
46  SDOperand Root, EntryNode;
47
48  // AllNodes - A linked list of nodes in the current DAG.
49  ilist<SDNode> AllNodes;
50
51  // ValueNodes - track SrcValue nodes
52  std::map<std::pair<const Value*, int>, SDNode*> ValueNodes;
53
54public:
55  SelectionDAG(TargetLowering &tli, MachineFunction &mf) : TLI(tli), MF(mf) {
56    EntryNode = Root = getNode(ISD::EntryToken, MVT::Other);
57  }
58  ~SelectionDAG();
59
60  MachineFunction &getMachineFunction() const { return MF; }
61  const TargetMachine &getTarget() const;
62  TargetLowering &getTargetLoweringInfo() const { return TLI; }
63
64  /// viewGraph - Pop up a ghostview window with the DAG rendered using 'dot'.
65  ///
66  void viewGraph();
67
68
69  typedef ilist<SDNode>::const_iterator allnodes_const_iterator;
70  allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
71  allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
72  typedef ilist<SDNode>::iterator allnodes_iterator;
73  allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
74  allnodes_iterator allnodes_end() { return AllNodes.end(); }
75
76  /// getRoot - Return the root tag of the SelectionDAG.
77  ///
78  const SDOperand &getRoot() const { return Root; }
79
80  /// getEntryNode - Return the token chain corresponding to the entry of the
81  /// function.
82  const SDOperand &getEntryNode() const { return EntryNode; }
83
84  /// setRoot - Set the current root tag of the SelectionDAG.
85  ///
86  const SDOperand &setRoot(SDOperand N) { return Root = N; }
87
88  /// Combine - This iterates over the nodes in the SelectionDAG, folding
89  /// certain types of nodes together, or eliminating superfluous nodes.  When
90  /// the AfterLegalize argument is set to 'true', Combine takes care not to
91  /// generate any nodes that will be illegal on the target.
92  void Combine(bool AfterLegalize);
93
94  /// Legalize - This transforms the SelectionDAG into a SelectionDAG that is
95  /// compatible with the target instruction selector, as indicated by the
96  /// TargetLowering object.
97  ///
98  /// Note that this is an involved process that may invalidate pointers into
99  /// the graph.
100  void Legalize();
101
102  /// RemoveDeadNodes - This method deletes all unreachable nodes in the
103  /// SelectionDAG, including nodes (like loads) that have uses of their token
104  /// chain but no other uses and no side effect.  If a node is passed in as an
105  /// argument, it is used as the seed for node deletion.
106  void RemoveDeadNodes(SDNode *N = 0);
107
108  SDOperand getString(const std::string &Val);
109  SDOperand getConstant(uint64_t Val, MVT::ValueType VT);
110  SDOperand getTargetConstant(uint64_t Val, MVT::ValueType VT);
111  SDOperand getConstantFP(double Val, MVT::ValueType VT);
112  SDOperand getGlobalAddress(const GlobalValue *GV, MVT::ValueType VT,
113                             int offset = 0);
114  SDOperand getTargetGlobalAddress(const GlobalValue *GV, MVT::ValueType VT,
115                                   int offset = 0);
116  SDOperand getFrameIndex(int FI, MVT::ValueType VT);
117  SDOperand getTargetFrameIndex(int FI, MVT::ValueType VT);
118  SDOperand getConstantPool(Constant *C, MVT::ValueType VT);
119  SDOperand getTargetConstantPool(Constant *C, MVT::ValueType VT);
120  SDOperand getBasicBlock(MachineBasicBlock *MBB);
121  SDOperand getExternalSymbol(const char *Sym, MVT::ValueType VT);
122  SDOperand getTargetExternalSymbol(const char *Sym, MVT::ValueType VT);
123  SDOperand getValueType(MVT::ValueType);
124  SDOperand getRegister(unsigned Reg, MVT::ValueType VT);
125
126  SDOperand getCopyToReg(SDOperand Chain, unsigned Reg, SDOperand N) {
127    return getNode(ISD::CopyToReg, MVT::Other, Chain,
128                   getRegister(Reg, N.getValueType()), N);
129  }
130
131  // This version of the getCopyToReg method takes an extra operand, which
132  // indicates that there is potentially an incoming flag value (if Flag is not
133  // null) and that there should be a flag result.
134  SDOperand getCopyToReg(SDOperand Chain, unsigned Reg, SDOperand N,
135                         SDOperand Flag) {
136    std::vector<MVT::ValueType> VTs;
137    VTs.push_back(MVT::Other);
138    VTs.push_back(MVT::Flag);
139    std::vector<SDOperand> Ops;
140    Ops.push_back(Chain);
141    Ops.push_back(getRegister(Reg, N.getValueType()));
142    Ops.push_back(N);
143    if (Flag.Val) Ops.push_back(Flag);
144    return getNode(ISD::CopyToReg, VTs, Ops);
145  }
146
147  // Similar to last getCopyToReg() except parameter Reg is a SDOperand
148  SDOperand getCopyToReg(SDOperand Chain, SDOperand Reg, SDOperand N,
149                         SDOperand Flag) {
150    std::vector<MVT::ValueType> VTs;
151    VTs.push_back(MVT::Other);
152    VTs.push_back(MVT::Flag);
153    std::vector<SDOperand> Ops;
154    Ops.push_back(Chain);
155    Ops.push_back(Reg);
156    Ops.push_back(N);
157    if (Flag.Val) Ops.push_back(Flag);
158    return getNode(ISD::CopyToReg, VTs, Ops);
159  }
160
161  SDOperand getCopyFromReg(SDOperand Chain, unsigned Reg, MVT::ValueType VT) {
162    std::vector<MVT::ValueType> ResultTys;
163    ResultTys.push_back(VT);
164    ResultTys.push_back(MVT::Other);
165    std::vector<SDOperand> Ops;
166    Ops.push_back(Chain);
167    Ops.push_back(getRegister(Reg, VT));
168    return getNode(ISD::CopyFromReg, ResultTys, Ops);
169  }
170
171  // This version of the getCopyFromReg method takes an extra operand, which
172  // indicates that there is potentially an incoming flag value (if Flag is not
173  // null) and that there should be a flag result.
174  SDOperand getCopyFromReg(SDOperand Chain, unsigned Reg, MVT::ValueType VT,
175                           SDOperand Flag) {
176    std::vector<MVT::ValueType> ResultTys;
177    ResultTys.push_back(VT);
178    ResultTys.push_back(MVT::Other);
179    ResultTys.push_back(MVT::Flag);
180    std::vector<SDOperand> Ops;
181    Ops.push_back(Chain);
182    Ops.push_back(getRegister(Reg, VT));
183    if (Flag.Val) Ops.push_back(Flag);
184    return getNode(ISD::CopyFromReg, ResultTys, Ops);
185  }
186
187  /// getCall - Note that this destroys the vector of RetVals passed in.
188  ///
189  SDNode *getCall(std::vector<MVT::ValueType> &RetVals, SDOperand Chain,
190                  SDOperand Callee, bool isTailCall = false) {
191    SDNode *NN = new SDNode(isTailCall ? ISD::TAILCALL : ISD::CALL, Chain,
192                            Callee);
193    setNodeValueTypes(NN, RetVals);
194    AllNodes.push_back(NN);
195    return NN;
196  }
197  /// getCall - Note that this destroys the vector of RetVals passed in.
198  ///
199  SDNode *getCall(std::vector<MVT::ValueType> &RetVals, SDOperand Chain,
200                  SDOperand Callee, SDOperand Flag, bool isTailCall = false) {
201    SDNode *NN = new SDNode(isTailCall ? ISD::TAILCALL : ISD::CALL, Chain,
202                            Callee, Flag);
203    setNodeValueTypes(NN, RetVals);
204    AllNodes.push_back(NN);
205    return NN;
206  }
207
208  /// getCall - This is identical to the one above, and should be used for calls
209  /// where arguments are passed in physical registers.  This destroys the
210  /// RetVals and ArgsInRegs vectors.
211  SDNode *getCall(std::vector<MVT::ValueType> &RetVals, SDOperand Chain,
212                  SDOperand Callee, std::vector<SDOperand> &ArgsInRegs,
213                  bool isTailCall = false) {
214    ArgsInRegs.insert(ArgsInRegs.begin(), Callee);
215    ArgsInRegs.insert(ArgsInRegs.begin(), Chain);
216    SDNode *NN = new SDNode(isTailCall ? ISD::TAILCALL : ISD::CALL, ArgsInRegs);
217    setNodeValueTypes(NN, RetVals);
218    AllNodes.push_back(NN);
219    return NN;
220  }
221
222  SDOperand getCondCode(ISD::CondCode Cond);
223
224  /// getZeroExtendInReg - Return the expression required to zero extend the Op
225  /// value assuming it was the smaller SrcTy value.
226  SDOperand getZeroExtendInReg(SDOperand Op, MVT::ValueType SrcTy);
227
228  /// getNode - Gets or creates the specified node.
229  ///
230  SDOperand getNode(unsigned Opcode, MVT::ValueType VT);
231  SDOperand getNode(unsigned Opcode, MVT::ValueType VT, SDOperand N);
232  SDOperand getNode(unsigned Opcode, MVT::ValueType VT,
233                    SDOperand N1, SDOperand N2);
234  SDOperand getNode(unsigned Opcode, MVT::ValueType VT,
235                    SDOperand N1, SDOperand N2, SDOperand N3);
236  SDOperand getNode(unsigned Opcode, MVT::ValueType VT,
237                    SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4);
238  SDOperand getNode(unsigned Opcode, MVT::ValueType VT,
239                    SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4,
240                    SDOperand N5);
241  SDOperand getNode(unsigned Opcode, MVT::ValueType VT,
242                    SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4,
243                    SDOperand N5, SDOperand N6);
244  SDOperand getNode(unsigned Opcode, MVT::ValueType VT,
245                    std::vector<SDOperand> &Children);
246  SDOperand getNode(unsigned Opcode, std::vector<MVT::ValueType> &ResultTys,
247                    std::vector<SDOperand> &Ops);
248
249  /// getSetCC - Helper function to make it easier to build SetCC's if you just
250  /// have an ISD::CondCode instead of an SDOperand.
251  ///
252  SDOperand getSetCC(MVT::ValueType VT, SDOperand LHS, SDOperand RHS,
253                     ISD::CondCode Cond) {
254    return getNode(ISD::SETCC, VT, LHS, RHS, getCondCode(Cond));
255  }
256
257  /// getSelectCC - Helper function to make it easier to build SelectCC's if you
258  /// just have an ISD::CondCode instead of an SDOperand.
259  ///
260  SDOperand getSelectCC(SDOperand LHS, SDOperand RHS,
261                        SDOperand True, SDOperand False, ISD::CondCode Cond) {
262    MVT::ValueType VT = True.getValueType();
263    return getNode(ISD::SELECT_CC, VT, LHS, RHS, True, False,getCondCode(Cond));
264  }
265
266  /// getBR2Way_CC - Helper function to make it easier to build BRTWOWAY_CC
267  /// nodes.
268  ///
269  SDOperand getBR2Way_CC(SDOperand Chain, SDOperand CCNode, SDOperand LHS,
270                         SDOperand RHS, SDOperand True, SDOperand False) {
271    std::vector<SDOperand> Ops;
272    Ops.push_back(Chain);
273    Ops.push_back(CCNode);
274    Ops.push_back(LHS);
275    Ops.push_back(RHS);
276    Ops.push_back(True);
277    Ops.push_back(False);
278    return getNode(ISD::BRTWOWAY_CC, MVT::Other, Ops);
279  }
280
281  /// getLoad - Loads are not normal binary operators: their result type is not
282  /// determined by their operands, and they produce a value AND a token chain.
283  ///
284  SDOperand getLoad(MVT::ValueType VT, SDOperand Chain, SDOperand Ptr,
285                    SDOperand SV);
286  SDOperand getVecLoad(unsigned Count, MVT::ValueType VT, SDOperand Chain,
287                       SDOperand Ptr, SDOperand SV);
288  SDOperand getExtLoad(unsigned Opcode, MVT::ValueType VT, SDOperand Chain,
289                       SDOperand Ptr, SDOperand SV, MVT::ValueType EVT);
290
291  // getSrcValue - construct a node to track a Value* through the backend
292  SDOperand getSrcValue(const Value* I, int offset = 0);
293
294
295  /// SelectNodeTo - These are used for target selectors to *mutate* the
296  /// specified node to have the specified return type, Target opcode, and
297  /// operands.  Note that target opcodes are stored as
298  /// ISD::BUILTIN_OP_END+TargetOpcode in the node opcode field.  The 0th value
299  /// of the resultant node is returned.
300  SDOperand SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT);
301  SDOperand SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT,
302                         SDOperand Op1);
303  SDOperand SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT,
304                         SDOperand Op1, SDOperand Op2);
305  SDOperand SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT,
306                         SDOperand Op1, SDOperand Op2, SDOperand Op3);
307  SDOperand SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT,
308                         SDOperand Op1, SDOperand Op2, SDOperand Op3,
309                         SDOperand Op4);
310  SDOperand SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT,
311                         SDOperand Op1, SDOperand Op2, SDOperand Op3,
312                         SDOperand Op4, SDOperand Op5);
313  SDOperand SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT,
314                         SDOperand Op1, SDOperand Op2, SDOperand Op3,
315                         SDOperand Op4, SDOperand Op5, SDOperand Op6);
316  SDOperand SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT1,
317                         MVT::ValueType VT2, SDOperand Op1, SDOperand Op2);
318  SDOperand SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT1,
319                         MVT::ValueType VT2, SDOperand Op1, SDOperand Op2,
320                         SDOperand Op3);
321  SDOperand SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT1,
322                         MVT::ValueType VT2, SDOperand Op1, SDOperand Op2,
323                         SDOperand Op3, SDOperand Op4);
324  SDOperand SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT1,
325                         MVT::ValueType VT2, SDOperand Op1, SDOperand Op2,
326                         SDOperand Op3, SDOperand Op4, SDOperand Op5);
327
328  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT) {
329    return getNode(ISD::BUILTIN_OP_END+Opcode, VT);
330  }
331  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT,
332                          SDOperand Op1) {
333    return getNode(ISD::BUILTIN_OP_END+Opcode, VT, Op1);
334  }
335  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT,
336                          SDOperand Op1, SDOperand Op2) {
337    return getNode(ISD::BUILTIN_OP_END+Opcode, VT, Op1, Op2);
338  }
339  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT,
340                          SDOperand Op1, SDOperand Op2, SDOperand Op3) {
341    return getNode(ISD::BUILTIN_OP_END+Opcode, VT, Op1, Op2, Op3);
342  }
343  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT,
344                          SDOperand Op1, SDOperand Op2, SDOperand Op3,
345                          SDOperand Op4) {
346    return getNode(ISD::BUILTIN_OP_END+Opcode, VT, Op1, Op2, Op3, Op4);
347  }
348  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT,
349                          SDOperand Op1, SDOperand Op2, SDOperand Op3,
350                          SDOperand Op4, SDOperand Op5) {
351    return getNode(ISD::BUILTIN_OP_END+Opcode, VT, Op1, Op2, Op3, Op4, Op5);
352  }
353  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT,
354                          SDOperand Op1, SDOperand Op2, SDOperand Op3,
355                          SDOperand Op4, SDOperand Op5, SDOperand Op6) {
356    return getNode(ISD::BUILTIN_OP_END+Opcode, VT, Op1, Op2, Op3, Op4, Op5, Op6);
357  }
358  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT,
359                          std::vector<SDOperand> &Ops) {
360    return getNode(ISD::BUILTIN_OP_END+Opcode, VT, Ops);
361  }
362  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT1,
363                          MVT::ValueType VT2, SDOperand Op1) {
364    std::vector<MVT::ValueType> ResultTys;
365    ResultTys.push_back(VT1);
366    ResultTys.push_back(VT2);
367    std::vector<SDOperand> Ops;
368    Ops.push_back(Op1);
369    return getNode(ISD::BUILTIN_OP_END+Opcode, ResultTys, Ops);
370  }
371  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT1,
372                          MVT::ValueType VT2, SDOperand Op1, SDOperand Op2) {
373    std::vector<MVT::ValueType> ResultTys;
374    ResultTys.push_back(VT1);
375    ResultTys.push_back(VT2);
376    std::vector<SDOperand> Ops;
377    Ops.push_back(Op1);
378    Ops.push_back(Op2);
379    return getNode(ISD::BUILTIN_OP_END+Opcode, ResultTys, Ops);
380  }
381  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT1,
382                          MVT::ValueType VT2, SDOperand Op1, SDOperand Op2,
383                          SDOperand Op3) {
384    std::vector<MVT::ValueType> ResultTys;
385    ResultTys.push_back(VT1);
386    ResultTys.push_back(VT2);
387    std::vector<SDOperand> Ops;
388    Ops.push_back(Op1);
389    Ops.push_back(Op2);
390    Ops.push_back(Op3);
391    return getNode(ISD::BUILTIN_OP_END+Opcode, ResultTys, Ops);
392  }
393  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT1,
394                          MVT::ValueType VT2, SDOperand Op1, SDOperand Op2,
395                          SDOperand Op3, SDOperand Op4) {
396    std::vector<MVT::ValueType> ResultTys;
397    ResultTys.push_back(VT1);
398    ResultTys.push_back(VT2);
399    std::vector<SDOperand> Ops;
400    Ops.push_back(Op1);
401    Ops.push_back(Op2);
402    Ops.push_back(Op3);
403    Ops.push_back(Op4);
404    return getNode(ISD::BUILTIN_OP_END+Opcode, ResultTys, Ops);
405  }
406  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT1,
407                          MVT::ValueType VT2, SDOperand Op1, SDOperand Op2,
408                          SDOperand Op3, SDOperand Op4, SDOperand Op5) {
409    std::vector<MVT::ValueType> ResultTys;
410    ResultTys.push_back(VT1);
411    ResultTys.push_back(VT2);
412    std::vector<SDOperand> Ops;
413    Ops.push_back(Op1);
414    Ops.push_back(Op2);
415    Ops.push_back(Op3);
416    Ops.push_back(Op4);
417    Ops.push_back(Op5);
418    return getNode(ISD::BUILTIN_OP_END+Opcode, ResultTys, Ops);
419  }
420  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT1,
421                          MVT::ValueType VT2, SDOperand Op1, SDOperand Op2,
422                          SDOperand Op3, SDOperand Op4, SDOperand Op5,
423                          SDOperand Op6) {
424    std::vector<MVT::ValueType> ResultTys;
425    ResultTys.push_back(VT1);
426    ResultTys.push_back(VT2);
427    std::vector<SDOperand> Ops;
428    Ops.push_back(Op1);
429    Ops.push_back(Op2);
430    Ops.push_back(Op3);
431    Ops.push_back(Op4);
432    Ops.push_back(Op5);
433    Ops.push_back(Op6);
434    return getNode(ISD::BUILTIN_OP_END+Opcode, ResultTys, Ops);
435  }
436  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT1,
437                          MVT::ValueType VT2, SDOperand Op1, SDOperand Op2,
438                          SDOperand Op3, SDOperand Op4, SDOperand Op5,
439                          SDOperand Op6, SDOperand Op7) {
440    std::vector<MVT::ValueType> ResultTys;
441    ResultTys.push_back(VT1);
442    ResultTys.push_back(VT2);
443    std::vector<SDOperand> Ops;
444    Ops.push_back(Op1);
445    Ops.push_back(Op2);
446    Ops.push_back(Op3);
447    Ops.push_back(Op4);
448    Ops.push_back(Op5);
449    Ops.push_back(Op6);
450    Ops.push_back(Op7);
451   return getNode(ISD::BUILTIN_OP_END+Opcode, ResultTys, Ops);
452  }
453  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT1,
454                          MVT::ValueType VT2, std::vector<SDOperand> &Ops) {
455    std::vector<MVT::ValueType> ResultTys;
456    ResultTys.push_back(VT1);
457    ResultTys.push_back(VT2);
458    return getNode(ISD::BUILTIN_OP_END+Opcode, ResultTys, Ops);
459  }
460
461  /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
462  /// This can cause recursive merging of nodes in the DAG.  Use the first
463  /// version if 'From' is known to have a single result, use the second
464  /// if you have two nodes with identical results, use the third otherwise.
465  ///
466  /// These methods all take an optional vector, which (if not null) is
467  /// populated with any nodes that are deleted from the SelectionDAG, due to
468  /// new equivalences that are discovered.
469  ///
470  void ReplaceAllUsesWith(SDOperand From, SDOperand Op,
471                          std::vector<SDNode*> *Deleted = 0);
472  void ReplaceAllUsesWith(SDNode *From, SDNode *To,
473                          std::vector<SDNode*> *Deleted = 0);
474  void ReplaceAllUsesWith(SDNode *From, const std::vector<SDOperand> &To,
475                          std::vector<SDNode*> *Deleted = 0);
476
477
478  /// DeleteNode - Remove the specified node from the system.  This node must
479  /// have no referrers.
480  void DeleteNode(SDNode *N);
481
482  void dump() const;
483
484private:
485  void RemoveNodeFromCSEMaps(SDNode *N);
486  SDNode *AddNonLeafNodeToCSEMaps(SDNode *N);
487  void DestroyDeadNode(SDNode *N);
488  void DeleteNodeNotInCSEMaps(SDNode *N);
489  void setNodeValueTypes(SDNode *N, std::vector<MVT::ValueType> &RetVals);
490  void setNodeValueTypes(SDNode *N, MVT::ValueType VT1, MVT::ValueType VT2);
491
492
493  /// SimplifySetCC - Try to simplify a setcc built with the specified operands
494  /// and cc.  If unable to simplify it, return a null SDOperand.
495  SDOperand SimplifySetCC(MVT::ValueType VT, SDOperand N1,
496                          SDOperand N2, ISD::CondCode Cond);
497
498  // List of non-single value types.
499  std::list<std::vector<MVT::ValueType> > VTList;
500
501  // Maps to auto-CSE operations.
502  std::map<std::pair<unsigned, MVT::ValueType>, SDNode *> NullaryOps;
503  std::map<std::pair<unsigned, std::pair<SDOperand, MVT::ValueType> >,
504           SDNode *> UnaryOps;
505  std::map<std::pair<unsigned, std::pair<SDOperand, SDOperand> >,
506           SDNode *> BinaryOps;
507
508  std::map<std::pair<unsigned, MVT::ValueType>, RegisterSDNode*> RegNodes;
509  std::vector<CondCodeSDNode*> CondCodeNodes;
510
511  std::map<std::pair<SDOperand, std::pair<SDOperand, MVT::ValueType> >,
512           SDNode *> Loads;
513
514  std::map<std::pair<const GlobalValue*, int>, SDNode*> GlobalValues;
515  std::map<std::pair<const GlobalValue*, int>, SDNode*> TargetGlobalValues;
516  std::map<std::pair<uint64_t, MVT::ValueType>, SDNode*> Constants;
517  std::map<std::pair<uint64_t, MVT::ValueType>, SDNode*> TargetConstants;
518  std::map<std::pair<uint64_t, MVT::ValueType>, SDNode*> ConstantFPs;
519  std::map<int, SDNode*> FrameIndices, TargetFrameIndices;
520  std::map<Constant *, SDNode*> ConstantPoolIndices;
521  std::map<Constant *, SDNode*> TargetConstantPoolIndices;
522  std::map<MachineBasicBlock *, SDNode*> BBNodes;
523  std::vector<SDNode*> ValueTypeNodes;
524  std::map<std::string, SDNode*> ExternalSymbols;
525  std::map<std::string, SDNode*> TargetExternalSymbols;
526  std::map<std::string, StringSDNode*> StringNodes;
527  std::map<std::pair<unsigned,
528                     std::pair<MVT::ValueType, std::vector<SDOperand> > >,
529           SDNode*> OneResultNodes;
530  std::map<std::pair<unsigned,
531                     std::pair<std::vector<MVT::ValueType>,
532                               std::vector<SDOperand> > >,
533           SDNode*> ArbitraryNodes;
534};
535
536template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
537  typedef SelectionDAG::allnodes_iterator nodes_iterator;
538  static nodes_iterator nodes_begin(SelectionDAG *G) {
539    return G->allnodes_begin();
540  }
541  static nodes_iterator nodes_end(SelectionDAG *G) {
542    return G->allnodes_end();
543  }
544};
545
546}  // end namespace llvm
547
548#endif
549