1 //===-- llvm/CodeGen/SelectionDAG.h - InstSelection DAG ---------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file declares the SelectionDAG class, and transitively defines the
11 // SDNode class and subclasses.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_CODEGEN_SELECTIONDAG_H
16 #define LLVM_CODEGEN_SELECTIONDAG_H
18 #include "llvm/ADT/ilist.h"
19 #include "llvm/ADT/FoldingSet.h"
20 #include "llvm/ADT/StringMap.h"
21 #include "llvm/CodeGen/SelectionDAGNodes.h"
34 class MachineModuleInfo;
35 class MachineFunction;
36 class MachineConstantPoolValue;
37 class FunctionLoweringInfo;
39 template<> class ilist_traits<SDNode> : public ilist_default_traits<SDNode> {
40 mutable SDNode Sentinel;
42 ilist_traits() : Sentinel(ISD::DELETED_NODE, SDVTList()) {}
44 SDNode *createSentinel() const {
47 static void destroySentinel(SDNode *) {}
49 static void deleteNode(SDNode *) {
50 assert(0 && "ilist_traits<SDNode> shouldn't see a deleteNode call!");
53 static void createNode(const SDNode &);
56 /// SelectionDAG class - This is used to represent a portion of an LLVM function
57 /// in a low-level Data Dependence DAG representation suitable for instruction
58 /// selection. This DAG is constructed as the first step of instruction
59 /// selection in order to allow implementation of machine specific optimizations
60 /// and code simplifications.
62 /// The representation used by the SelectionDAG is a target-independent
63 /// representation, which has some similarities to the GCC RTL representation,
64 /// but is significantly more simple, powerful, and is a graph form instead of a
70 FunctionLoweringInfo &FLI;
71 MachineModuleInfo *MMI;
73 /// EntryNode - The starting token.
76 /// Root - The root of the entire DAG.
79 /// AllNodes - A linked list of nodes in the current DAG.
80 ilist<SDNode> AllNodes;
82 /// NodeAllocatorType - The AllocatorType for allocating SDNodes. We use
83 /// pool allocation with recycling.
84 typedef RecyclingAllocator<BumpPtrAllocator, SDNode, sizeof(LargestSDNode),
85 AlignOf<MostAlignedSDNode>::Alignment>
88 /// NodeAllocator - Pool allocation for nodes.
89 NodeAllocatorType NodeAllocator;
91 /// CSEMap - This structure is used to memoize nodes, automatically performing
92 /// CSE with existing nodes with a duplicate is requested.
93 FoldingSet<SDNode> CSEMap;
95 /// OperandAllocator - Pool allocation for machine-opcode SDNode operands.
96 BumpPtrAllocator OperandAllocator;
98 /// Allocator - Pool allocation for misc. objects that are created once per
100 BumpPtrAllocator Allocator;
102 /// VerifyNode - Sanity check the given node. Aborts if it is invalid.
103 void VerifyNode(SDNode *N);
106 SelectionDAG(TargetLowering &tli, MachineFunction &mf,
107 FunctionLoweringInfo &fli, MachineModuleInfo *mmi);
110 /// reset - Clear state and free memory necessary to make this
111 /// SelectionDAG ready to process a new block.
115 MachineFunction &getMachineFunction() const { return MF; }
116 const TargetMachine &getTarget() const;
117 TargetLowering &getTargetLoweringInfo() const { return TLI; }
118 FunctionLoweringInfo &getFunctionLoweringInfo() const { return FLI; }
119 MachineModuleInfo *getMachineModuleInfo() const { return MMI; }
121 /// viewGraph - Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
123 void viewGraph(const std::string &Title);
127 std::map<const SDNode *, std::string> NodeGraphAttrs;
130 /// clearGraphAttrs - Clear all previously defined node graph attributes.
131 /// Intended to be used from a debugging tool (eg. gdb).
132 void clearGraphAttrs();
134 /// setGraphAttrs - Set graph attributes for a node. (eg. "color=red".)
136 void setGraphAttrs(const SDNode *N, const char *Attrs);
138 /// getGraphAttrs - Get graph attributes for a node. (eg. "color=red".)
139 /// Used from getNodeAttributes.
140 const std::string getGraphAttrs(const SDNode *N) const;
142 /// setGraphColor - Convenience for setting node color attribute.
144 void setGraphColor(const SDNode *N, const char *Color);
146 typedef ilist<SDNode>::const_iterator allnodes_const_iterator;
147 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
148 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
149 typedef ilist<SDNode>::iterator allnodes_iterator;
150 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
151 allnodes_iterator allnodes_end() { return AllNodes.end(); }
152 ilist<SDNode>::size_type allnodes_size() const {
153 return AllNodes.size();
156 /// getRoot - Return the root tag of the SelectionDAG.
158 const SDValue &getRoot() const { return Root; }
160 /// getEntryNode - Return the token chain corresponding to the entry of the
162 SDValue getEntryNode() const {
163 return SDValue(const_cast<SDNode *>(&EntryNode), 0);
166 /// setRoot - Set the current root tag of the SelectionDAG.
168 const SDValue &setRoot(SDValue N) {
169 assert((!N.Val || N.getValueType() == MVT::Other) &&
170 "DAG root value is not a chain!");
174 /// Combine - This iterates over the nodes in the SelectionDAG, folding
175 /// certain types of nodes together, or eliminating superfluous nodes. When
176 /// the AfterLegalize argument is set to 'true', Combine takes care not to
177 /// generate any nodes that will be illegal on the target.
178 void Combine(bool AfterLegalize, AliasAnalysis &AA, bool Fast);
180 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that
181 /// only uses types natively supported by the target.
183 /// Note that this is an involved process that may invalidate pointers into
185 void LegalizeTypes();
187 /// Legalize - This transforms the SelectionDAG into a SelectionDAG that is
188 /// compatible with the target instruction selector, as indicated by the
189 /// TargetLowering object.
191 /// Note that this is an involved process that may invalidate pointers into
195 /// RemoveDeadNodes - This method deletes all unreachable nodes in the
197 void RemoveDeadNodes();
199 /// DeleteNode - Remove the specified node from the system. This node must
200 /// have no referrers.
201 void DeleteNode(SDNode *N);
203 /// getVTList - Return an SDVTList that represents the list of values
205 SDVTList getVTList(MVT VT);
206 SDVTList getVTList(MVT VT1, MVT VT2);
207 SDVTList getVTList(MVT VT1, MVT VT2, MVT VT3);
208 SDVTList getVTList(const MVT *VTs, unsigned NumVTs);
210 /// getNodeValueTypes - These are obsolete, use getVTList instead.
211 const MVT *getNodeValueTypes(MVT VT) {
212 return getVTList(VT).VTs;
214 const MVT *getNodeValueTypes(MVT VT1, MVT VT2) {
215 return getVTList(VT1, VT2).VTs;
217 const MVT *getNodeValueTypes(MVT VT1, MVT VT2, MVT VT3) {
218 return getVTList(VT1, VT2, VT3).VTs;
220 const MVT *getNodeValueTypes(const std::vector<MVT> &vtList) {
221 return getVTList(&vtList[0], (unsigned)vtList.size()).VTs;
225 //===--------------------------------------------------------------------===//
226 // Node creation methods.
228 SDValue getConstant(uint64_t Val, MVT VT, bool isTarget = false);
229 SDValue getConstant(const APInt &Val, MVT VT, bool isTarget = false);
230 SDValue getIntPtrConstant(uint64_t Val, bool isTarget = false);
231 SDValue getTargetConstant(uint64_t Val, MVT VT) {
232 return getConstant(Val, VT, true);
234 SDValue getTargetConstant(const APInt &Val, MVT VT) {
235 return getConstant(Val, VT, true);
237 SDValue getConstantFP(double Val, MVT VT, bool isTarget = false);
238 SDValue getConstantFP(const APFloat& Val, MVT VT, bool isTarget = false);
239 SDValue getTargetConstantFP(double Val, MVT VT) {
240 return getConstantFP(Val, VT, true);
242 SDValue getTargetConstantFP(const APFloat& Val, MVT VT) {
243 return getConstantFP(Val, VT, true);
245 SDValue getGlobalAddress(const GlobalValue *GV, MVT VT,
246 int offset = 0, bool isTargetGA = false);
247 SDValue getTargetGlobalAddress(const GlobalValue *GV, MVT VT,
249 return getGlobalAddress(GV, VT, offset, true);
251 SDValue getFrameIndex(int FI, MVT VT, bool isTarget = false);
252 SDValue getTargetFrameIndex(int FI, MVT VT) {
253 return getFrameIndex(FI, VT, true);
255 SDValue getJumpTable(int JTI, MVT VT, bool isTarget = false);
256 SDValue getTargetJumpTable(int JTI, MVT VT) {
257 return getJumpTable(JTI, VT, true);
259 SDValue getConstantPool(Constant *C, MVT VT,
260 unsigned Align = 0, int Offs = 0, bool isT=false);
261 SDValue getTargetConstantPool(Constant *C, MVT VT,
262 unsigned Align = 0, int Offset = 0) {
263 return getConstantPool(C, VT, Align, Offset, true);
265 SDValue getConstantPool(MachineConstantPoolValue *C, MVT VT,
266 unsigned Align = 0, int Offs = 0, bool isT=false);
267 SDValue getTargetConstantPool(MachineConstantPoolValue *C,
268 MVT VT, unsigned Align = 0,
270 return getConstantPool(C, VT, Align, Offset, true);
272 SDValue getBasicBlock(MachineBasicBlock *MBB);
273 SDValue getExternalSymbol(const char *Sym, MVT VT);
274 SDValue getTargetExternalSymbol(const char *Sym, MVT VT);
275 SDValue getArgFlags(ISD::ArgFlagsTy Flags);
276 SDValue getValueType(MVT);
277 SDValue getRegister(unsigned Reg, MVT VT);
278 SDValue getDbgStopPoint(SDValue Root, unsigned Line, unsigned Col,
279 const CompileUnitDesc *CU);
280 SDValue getLabel(unsigned Opcode, SDValue Root, unsigned LabelID);
282 SDValue getCopyToReg(SDValue Chain, unsigned Reg, SDValue N) {
283 return getNode(ISD::CopyToReg, MVT::Other, Chain,
284 getRegister(Reg, N.getValueType()), N);
287 // This version of the getCopyToReg method takes an extra operand, which
288 // indicates that there is potentially an incoming flag value (if Flag is not
289 // null) and that there should be a flag result.
290 SDValue getCopyToReg(SDValue Chain, unsigned Reg, SDValue N,
292 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
293 SDValue Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Flag };
294 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.Val ? 4 : 3);
297 // Similar to last getCopyToReg() except parameter Reg is a SDValue
298 SDValue getCopyToReg(SDValue Chain, SDValue Reg, SDValue N,
300 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
301 SDValue Ops[] = { Chain, Reg, N, Flag };
302 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.Val ? 4 : 3);
305 SDValue getCopyFromReg(SDValue Chain, unsigned Reg, MVT VT) {
306 const MVT *VTs = getNodeValueTypes(VT, MVT::Other);
307 SDValue Ops[] = { Chain, getRegister(Reg, VT) };
308 return getNode(ISD::CopyFromReg, VTs, 2, Ops, 2);
311 // This version of the getCopyFromReg method takes an extra operand, which
312 // indicates that there is potentially an incoming flag value (if Flag is not
313 // null) and that there should be a flag result.
314 SDValue getCopyFromReg(SDValue Chain, unsigned Reg, MVT VT,
316 const MVT *VTs = getNodeValueTypes(VT, MVT::Other, MVT::Flag);
317 SDValue Ops[] = { Chain, getRegister(Reg, VT), Flag };
318 return getNode(ISD::CopyFromReg, VTs, 3, Ops, Flag.Val ? 3 : 2);
321 SDValue getCondCode(ISD::CondCode Cond);
323 /// getZeroExtendInReg - Return the expression required to zero extend the Op
324 /// value assuming it was the smaller SrcTy value.
325 SDValue getZeroExtendInReg(SDValue Op, MVT SrcTy);
327 /// getCALLSEQ_START - Return a new CALLSEQ_START node, which always must have
328 /// a flag result (to ensure it's not CSE'd).
329 SDValue getCALLSEQ_START(SDValue Chain, SDValue Op) {
330 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
331 SDValue Ops[] = { Chain, Op };
332 return getNode(ISD::CALLSEQ_START, VTs, 2, Ops, 2);
335 /// getCALLSEQ_END - Return a new CALLSEQ_END node, which always must have a
336 /// flag result (to ensure it's not CSE'd).
337 SDValue getCALLSEQ_END(SDValue Chain, SDValue Op1, SDValue Op2,
339 SDVTList NodeTys = getVTList(MVT::Other, MVT::Flag);
340 SmallVector<SDValue, 4> Ops;
341 Ops.push_back(Chain);
344 Ops.push_back(InFlag);
345 return getNode(ISD::CALLSEQ_END, NodeTys, &Ops[0],
346 (unsigned)Ops.size() - (InFlag.Val == 0 ? 1 : 0));
349 /// getNode - Gets or creates the specified node.
351 SDValue getNode(unsigned Opcode, MVT VT);
352 SDValue getNode(unsigned Opcode, MVT VT, SDValue N);
353 SDValue getNode(unsigned Opcode, MVT VT, SDValue N1, SDValue N2);
354 SDValue getNode(unsigned Opcode, MVT VT,
355 SDValue N1, SDValue N2, SDValue N3);
356 SDValue getNode(unsigned Opcode, MVT VT,
357 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
358 SDValue getNode(unsigned Opcode, MVT VT,
359 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
361 SDValue getNode(unsigned Opcode, MVT VT,
362 const SDValue *Ops, unsigned NumOps);
363 SDValue getNode(unsigned Opcode, MVT VT,
364 const SDUse *Ops, unsigned NumOps);
365 SDValue getNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
366 const SDValue *Ops, unsigned NumOps);
367 SDValue getNode(unsigned Opcode, const MVT *VTs, unsigned NumVTs,
368 const SDValue *Ops, unsigned NumOps);
369 SDValue getNode(unsigned Opcode, SDVTList VTs);
370 SDValue getNode(unsigned Opcode, SDVTList VTs, SDValue N);
371 SDValue getNode(unsigned Opcode, SDVTList VTs, SDValue N1, SDValue N2);
372 SDValue getNode(unsigned Opcode, SDVTList VTs,
373 SDValue N1, SDValue N2, SDValue N3);
374 SDValue getNode(unsigned Opcode, SDVTList VTs,
375 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
376 SDValue getNode(unsigned Opcode, SDVTList VTs,
377 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
379 SDValue getNode(unsigned Opcode, SDVTList VTs,
380 const SDValue *Ops, unsigned NumOps);
382 SDValue getMemcpy(SDValue Chain, SDValue Dst, SDValue Src,
383 SDValue Size, unsigned Align,
385 const Value *DstSV, uint64_t DstSVOff,
386 const Value *SrcSV, uint64_t SrcSVOff);
388 SDValue getMemmove(SDValue Chain, SDValue Dst, SDValue Src,
389 SDValue Size, unsigned Align,
390 const Value *DstSV, uint64_t DstOSVff,
391 const Value *SrcSV, uint64_t SrcSVOff);
393 SDValue getMemset(SDValue Chain, SDValue Dst, SDValue Src,
394 SDValue Size, unsigned Align,
395 const Value *DstSV, uint64_t DstSVOff);
397 /// getSetCC - Helper function to make it easier to build SetCC's if you just
398 /// have an ISD::CondCode instead of an SDValue.
400 SDValue getSetCC(MVT VT, SDValue LHS, SDValue RHS,
401 ISD::CondCode Cond) {
402 return getNode(ISD::SETCC, VT, LHS, RHS, getCondCode(Cond));
405 /// getVSetCC - Helper function to make it easier to build VSetCC's nodes
406 /// if you just have an ISD::CondCode instead of an SDValue.
408 SDValue getVSetCC(MVT VT, SDValue LHS, SDValue RHS,
409 ISD::CondCode Cond) {
410 return getNode(ISD::VSETCC, VT, LHS, RHS, getCondCode(Cond));
413 /// getSelectCC - Helper function to make it easier to build SelectCC's if you
414 /// just have an ISD::CondCode instead of an SDValue.
416 SDValue getSelectCC(SDValue LHS, SDValue RHS,
417 SDValue True, SDValue False, ISD::CondCode Cond) {
418 return getNode(ISD::SELECT_CC, True.getValueType(), LHS, RHS, True, False,
422 /// getVAArg - VAArg produces a result and token chain, and takes a pointer
423 /// and a source value as input.
424 SDValue getVAArg(MVT VT, SDValue Chain, SDValue Ptr,
427 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
429 SDValue getAtomic(unsigned Opcode, SDValue Chain, SDValue Ptr,
430 SDValue Cmp, SDValue Swp, const Value* PtrVal,
431 unsigned Alignment=0);
433 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
435 SDValue getAtomic(unsigned Opcode, SDValue Chain, SDValue Ptr,
436 SDValue Val, const Value* PtrVal,
437 unsigned Alignment = 0);
439 /// getMergeValues - Create a MERGE_VALUES node from the given operands.
440 /// Allowed to return something different (and simpler) if Simplify is true.
441 SDValue getMergeValues(const SDValue *Ops, unsigned NumOps,
442 bool Simplify = true);
444 /// getMergeValues - Create a MERGE_VALUES node from the given types and ops.
445 /// Allowed to return something different (and simpler) if Simplify is true.
446 /// May be faster than the above version if VTs is known and NumOps is large.
447 SDValue getMergeValues(SDVTList VTs, const SDValue *Ops, unsigned NumOps,
448 bool Simplify = true) {
449 if (Simplify && NumOps == 1)
451 return getNode(ISD::MERGE_VALUES, VTs, Ops, NumOps);
454 /// getLoad - Loads are not normal binary operators: their result type is not
455 /// determined by their operands, and they produce a value AND a token chain.
457 SDValue getLoad(MVT VT, SDValue Chain, SDValue Ptr,
458 const Value *SV, int SVOffset, bool isVolatile=false,
459 unsigned Alignment=0);
460 SDValue getExtLoad(ISD::LoadExtType ExtType, MVT VT,
461 SDValue Chain, SDValue Ptr, const Value *SV,
462 int SVOffset, MVT EVT, bool isVolatile=false,
463 unsigned Alignment=0);
464 SDValue getIndexedLoad(SDValue OrigLoad, SDValue Base,
465 SDValue Offset, ISD::MemIndexedMode AM);
466 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
467 MVT VT, SDValue Chain,
468 SDValue Ptr, SDValue Offset,
469 const Value *SV, int SVOffset, MVT EVT,
470 bool isVolatile=false, unsigned Alignment=0);
472 /// getStore - Helper function to build ISD::STORE nodes.
474 SDValue getStore(SDValue Chain, SDValue Val, SDValue Ptr,
475 const Value *SV, int SVOffset, bool isVolatile=false,
476 unsigned Alignment=0);
477 SDValue getTruncStore(SDValue Chain, SDValue Val, SDValue Ptr,
478 const Value *SV, int SVOffset, MVT TVT,
479 bool isVolatile=false, unsigned Alignment=0);
480 SDValue getIndexedStore(SDValue OrigStoe, SDValue Base,
481 SDValue Offset, ISD::MemIndexedMode AM);
483 // getSrcValue - Construct a node to track a Value* through the backend.
484 SDValue getSrcValue(const Value *v);
486 // getMemOperand - Construct a node to track a memory reference
487 // through the backend.
488 SDValue getMemOperand(const MachineMemOperand &MO);
490 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the
491 /// specified operands. If the resultant node already exists in the DAG,
492 /// this does not modify the specified node, instead it returns the node that
493 /// already exists. If the resultant node does not exist in the DAG, the
494 /// input node is returned. As a degenerate case, if you specify the same
495 /// input operands as the node already has, the input node is returned.
496 SDValue UpdateNodeOperands(SDValue N, SDValue Op);
497 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2);
498 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
500 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
501 SDValue Op3, SDValue Op4);
502 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
503 SDValue Op3, SDValue Op4, SDValue Op5);
504 SDValue UpdateNodeOperands(SDValue N,
505 const SDValue *Ops, unsigned NumOps);
507 /// SelectNodeTo - These are used for target selectors to *mutate* the
508 /// specified node to have the specified return type, Target opcode, and
509 /// operands. Note that target opcodes are stored as
510 /// ~TargetOpcode in the node opcode field. The resultant node is returned.
511 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT);
512 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, SDValue Op1);
513 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
514 SDValue Op1, SDValue Op2);
515 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
516 SDValue Op1, SDValue Op2, SDValue Op3);
517 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
518 const SDValue *Ops, unsigned NumOps);
519 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, MVT VT2);
520 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
521 MVT VT2, const SDValue *Ops, unsigned NumOps);
522 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
523 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps);
524 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
525 MVT VT2, SDValue Op1);
526 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
527 MVT VT2, SDValue Op1, SDValue Op2);
528 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
529 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
530 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
531 const SDValue *Ops, unsigned NumOps);
533 /// MorphNodeTo - These *mutate* the specified node to have the specified
534 /// return type, opcode, and operands.
535 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT);
536 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT, SDValue Op1);
537 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
538 SDValue Op1, SDValue Op2);
539 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
540 SDValue Op1, SDValue Op2, SDValue Op3);
541 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
542 const SDValue *Ops, unsigned NumOps);
543 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1, MVT VT2);
544 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
545 MVT VT2, const SDValue *Ops, unsigned NumOps);
546 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
547 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps);
548 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
549 MVT VT2, SDValue Op1);
550 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
551 MVT VT2, SDValue Op1, SDValue Op2);
552 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
553 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
554 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
555 const SDValue *Ops, unsigned NumOps);
557 /// getTargetNode - These are used for target selectors to create a new node
558 /// with specified return type(s), target opcode, and operands.
560 /// Note that getTargetNode returns the resultant node. If there is already a
561 /// node of the specified opcode and operands, it returns that node instead of
563 SDNode *getTargetNode(unsigned Opcode, MVT VT);
564 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1);
565 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1, SDValue Op2);
566 SDNode *getTargetNode(unsigned Opcode, MVT VT,
567 SDValue Op1, SDValue Op2, SDValue Op3);
568 SDNode *getTargetNode(unsigned Opcode, MVT VT,
569 const SDValue *Ops, unsigned NumOps);
570 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2);
571 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, SDValue Op1);
572 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
573 MVT VT2, SDValue Op1, SDValue Op2);
574 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
575 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
576 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2,
577 const SDValue *Ops, unsigned NumOps);
578 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
579 SDValue Op1, SDValue Op2);
580 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
581 SDValue Op1, SDValue Op2, SDValue Op3);
582 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
583 const SDValue *Ops, unsigned NumOps);
584 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, MVT VT4,
585 const SDValue *Ops, unsigned NumOps);
586 SDNode *getTargetNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
587 const SDValue *Ops, unsigned NumOps);
589 /// getNodeIfExists - Get the specified node if it's already available, or
590 /// else return NULL.
591 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs,
592 const SDValue *Ops, unsigned NumOps);
594 /// DAGUpdateListener - Clients of various APIs that cause global effects on
595 /// the DAG can optionally implement this interface. This allows the clients
596 /// to handle the various sorts of updates that happen.
597 class DAGUpdateListener {
599 virtual ~DAGUpdateListener();
601 /// NodeDeleted - The node N that was deleted and, if E is not null, an
602 /// equivalent node E that replaced it.
603 virtual void NodeDeleted(SDNode *N, SDNode *E) = 0;
605 /// NodeUpdated - The node N that was updated.
606 virtual void NodeUpdated(SDNode *N) = 0;
609 /// RemoveDeadNode - Remove the specified node from the system. If any of its
610 /// operands then becomes dead, remove them as well. Inform UpdateListener
611 /// for each node deleted.
612 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0);
614 /// RemoveDeadNodes - This method deletes the unreachable nodes in the
615 /// given list, and any nodes that become unreachable as a result.
616 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes,
617 DAGUpdateListener *UpdateListener = 0);
619 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
620 /// This can cause recursive merging of nodes in the DAG. Use the first
621 /// version if 'From' is known to have a single result, use the second
622 /// if you have two nodes with identical results, use the third otherwise.
624 /// These methods all take an optional UpdateListener, which (if not null) is
625 /// informed about nodes that are deleted and modified due to recursive
626 /// changes in the dag.
628 void ReplaceAllUsesWith(SDValue From, SDValue Op,
629 DAGUpdateListener *UpdateListener = 0);
630 void ReplaceAllUsesWith(SDNode *From, SDNode *To,
631 DAGUpdateListener *UpdateListener = 0);
632 void ReplaceAllUsesWith(SDNode *From, const SDValue *To,
633 DAGUpdateListener *UpdateListener = 0);
635 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving
636 /// uses of other values produced by From.Val alone.
637 void ReplaceAllUsesOfValueWith(SDValue From, SDValue To,
638 DAGUpdateListener *UpdateListener = 0);
640 /// ReplaceAllUsesOfValuesWith - Like ReplaceAllUsesOfValueWith, but
641 /// for multiple values at once. This correctly handles the case where
642 /// there is an overlap between the From values and the To values.
643 void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To,
645 DAGUpdateListener *UpdateListener = 0);
647 /// AssignTopologicalOrder - Assign a unique node id for each node in the DAG
648 /// based on their topological order. It returns the maximum id and a vector
649 /// of the SDNodes* in assigned order by reference.
650 unsigned AssignTopologicalOrder(std::vector<SDNode*> &TopOrder);
652 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary
654 static bool isCommutativeBinOp(unsigned Opcode) {
655 // FIXME: This should get its info from the td file, so that we can include
670 case ISD::ADDE: return true;
671 default: return false;
677 /// CreateStackTemporary - Create a stack temporary, suitable for holding the
678 /// specified value type. If minAlign is specified, the slot size will have
679 /// at least that alignment.
680 SDValue CreateStackTemporary(MVT VT, unsigned minAlign = 1);
682 /// FoldSetCC - Constant fold a setcc to true or false.
683 SDValue FoldSetCC(MVT VT, SDValue N1,
684 SDValue N2, ISD::CondCode Cond);
686 /// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We
687 /// use this predicate to simplify operations downstream.
688 bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const;
690 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We
691 /// use this predicate to simplify operations downstream. Op and Mask are
692 /// known to be the same type.
693 bool MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth = 0)
696 /// ComputeMaskedBits - Determine which of the bits specified in Mask are
697 /// known to be either zero or one and return them in the KnownZero/KnownOne
698 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit
699 /// processing. Targets can implement the computeMaskedBitsForTargetNode
700 /// method in the TargetLowering class to allow target nodes to be understood.
701 void ComputeMaskedBits(SDValue Op, const APInt &Mask, APInt &KnownZero,
702 APInt &KnownOne, unsigned Depth = 0) const;
704 /// ComputeNumSignBits - Return the number of times the sign bit of the
705 /// register is replicated into the other bits. We know that at least 1 bit
706 /// is always equal to the sign bit (itself), but other cases can give us
707 /// information. For example, immediately after an "SRA X, 2", we know that
708 /// the top 3 bits are all equal to each other, so we return 3. Targets can
709 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
710 /// class to allow target nodes to be understood.
711 unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const;
713 /// isVerifiedDebugInfoDesc - Returns true if the specified SDValue has
714 /// been verified as a debug information descriptor.
715 bool isVerifiedDebugInfoDesc(SDValue Op) const;
717 /// getShuffleScalarElt - Returns the scalar element that will make up the ith
718 /// element of the result of the vector shuffle.
719 SDValue getShuffleScalarElt(const SDNode *N, unsigned Idx);
722 void RemoveNodeFromCSEMaps(SDNode *N);
723 SDNode *AddNonLeafNodeToCSEMaps(SDNode *N);
724 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos);
725 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2,
727 SDNode *FindModifiedNodeSlot(SDNode *N, const SDValue *Ops, unsigned NumOps,
730 void DeleteNodeNotInCSEMaps(SDNode *N);
732 unsigned getMVTAlignment(MVT MemoryVT) const;
734 void allnodes_clear();
736 // List of non-single value types.
737 std::vector<SDVTList> VTList;
739 // Maps to auto-CSE operations.
740 std::vector<CondCodeSDNode*> CondCodeNodes;
742 std::vector<SDNode*> ValueTypeNodes;
743 std::map<MVT, SDNode*, MVT::compareRawBits> ExtendedValueTypeNodes;
744 StringMap<SDNode*> ExternalSymbols;
745 StringMap<SDNode*> TargetExternalSymbols;
748 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
749 typedef SelectionDAG::allnodes_iterator nodes_iterator;
750 static nodes_iterator nodes_begin(SelectionDAG *G) {
751 return G->allnodes_begin();
753 static nodes_iterator nodes_end(SelectionDAG *G) {
754 return G->allnodes_end();
758 } // end namespace llvm