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, FunctionLoweringInfo &fli);
109 /// init - Prepare this SelectionDAG to process code in the given
112 void init(MachineFunction &mf, MachineModuleInfo *mmi);
114 /// clear - Clear state and free memory necessary to make this
115 /// SelectionDAG ready to process a new block.
119 MachineFunction &getMachineFunction() const { return *MF; }
120 const TargetMachine &getTarget() const;
121 TargetLowering &getTargetLoweringInfo() const { return TLI; }
122 FunctionLoweringInfo &getFunctionLoweringInfo() const { return FLI; }
123 MachineModuleInfo *getMachineModuleInfo() const { return MMI; }
125 /// viewGraph - Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
127 void viewGraph(const std::string &Title);
131 std::map<const SDNode *, std::string> NodeGraphAttrs;
134 /// clearGraphAttrs - Clear all previously defined node graph attributes.
135 /// Intended to be used from a debugging tool (eg. gdb).
136 void clearGraphAttrs();
138 /// setGraphAttrs - Set graph attributes for a node. (eg. "color=red".)
140 void setGraphAttrs(const SDNode *N, const char *Attrs);
142 /// getGraphAttrs - Get graph attributes for a node. (eg. "color=red".)
143 /// Used from getNodeAttributes.
144 const std::string getGraphAttrs(const SDNode *N) const;
146 /// setGraphColor - Convenience for setting node color attribute.
148 void setGraphColor(const SDNode *N, const char *Color);
150 typedef ilist<SDNode>::const_iterator allnodes_const_iterator;
151 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
152 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
153 typedef ilist<SDNode>::iterator allnodes_iterator;
154 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
155 allnodes_iterator allnodes_end() { return AllNodes.end(); }
156 ilist<SDNode>::size_type allnodes_size() const {
157 return AllNodes.size();
160 /// getRoot - Return the root tag of the SelectionDAG.
162 const SDValue &getRoot() const { return Root; }
164 /// getEntryNode - Return the token chain corresponding to the entry of the
166 SDValue getEntryNode() const {
167 return SDValue(const_cast<SDNode *>(&EntryNode), 0);
170 /// setRoot - Set the current root tag of the SelectionDAG.
172 const SDValue &setRoot(SDValue N) {
173 assert((!N.getNode() || N.getValueType() == MVT::Other) &&
174 "DAG root value is not a chain!");
178 /// Combine - This iterates over the nodes in the SelectionDAG, folding
179 /// certain types of nodes together, or eliminating superfluous nodes. When
180 /// the AfterLegalize argument is set to 'true', Combine takes care not to
181 /// generate any nodes that will be illegal on the target.
182 void Combine(bool AfterLegalize, AliasAnalysis &AA, bool Fast);
184 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that
185 /// only uses types natively supported by the target.
187 /// Note that this is an involved process that may invalidate pointers into
189 void LegalizeTypes();
191 /// Legalize - This transforms the SelectionDAG into a SelectionDAG that is
192 /// compatible with the target instruction selector, as indicated by the
193 /// TargetLowering object.
195 /// Note that this is an involved process that may invalidate pointers into
199 /// RemoveDeadNodes - This method deletes all unreachable nodes in the
201 void RemoveDeadNodes();
203 /// DeleteNode - Remove the specified node from the system. This node must
204 /// have no referrers.
205 void DeleteNode(SDNode *N);
207 /// getVTList - Return an SDVTList that represents the list of values
209 SDVTList getVTList(MVT VT);
210 SDVTList getVTList(MVT VT1, MVT VT2);
211 SDVTList getVTList(MVT VT1, MVT VT2, MVT VT3);
212 SDVTList getVTList(const MVT *VTs, unsigned NumVTs);
214 /// getNodeValueTypes - These are obsolete, use getVTList instead.
215 const MVT *getNodeValueTypes(MVT VT) {
216 return getVTList(VT).VTs;
218 const MVT *getNodeValueTypes(MVT VT1, MVT VT2) {
219 return getVTList(VT1, VT2).VTs;
221 const MVT *getNodeValueTypes(MVT VT1, MVT VT2, MVT VT3) {
222 return getVTList(VT1, VT2, VT3).VTs;
224 const MVT *getNodeValueTypes(const std::vector<MVT> &vtList) {
225 return getVTList(&vtList[0], (unsigned)vtList.size()).VTs;
229 //===--------------------------------------------------------------------===//
230 // Node creation methods.
232 SDValue getConstant(uint64_t Val, MVT VT, bool isTarget = false);
233 SDValue getConstant(const APInt &Val, MVT VT, bool isTarget = false);
234 SDValue getConstant(const ConstantInt &Val, MVT VT, bool isTarget = false);
235 SDValue getIntPtrConstant(uint64_t Val, bool isTarget = false);
236 SDValue getTargetConstant(uint64_t Val, MVT VT) {
237 return getConstant(Val, VT, true);
239 SDValue getTargetConstant(const APInt &Val, MVT VT) {
240 return getConstant(Val, VT, true);
242 SDValue getTargetConstant(const ConstantInt &Val, MVT VT) {
243 return getConstant(Val, VT, true);
245 SDValue getConstantFP(double Val, MVT VT, bool isTarget = false);
246 SDValue getConstantFP(const APFloat& Val, MVT VT, bool isTarget = false);
247 SDValue getConstantFP(const ConstantFP &CF, MVT VT, bool isTarget = false);
248 SDValue getTargetConstantFP(double Val, MVT VT) {
249 return getConstantFP(Val, VT, true);
251 SDValue getTargetConstantFP(const APFloat& Val, MVT VT) {
252 return getConstantFP(Val, VT, true);
254 SDValue getTargetConstantFP(const ConstantFP &Val, MVT VT) {
255 return getConstantFP(Val, VT, true);
257 SDValue getGlobalAddress(const GlobalValue *GV, MVT VT,
258 int offset = 0, bool isTargetGA = false);
259 SDValue getTargetGlobalAddress(const GlobalValue *GV, MVT VT,
261 return getGlobalAddress(GV, VT, offset, true);
263 SDValue getFrameIndex(int FI, MVT VT, bool isTarget = false);
264 SDValue getTargetFrameIndex(int FI, MVT VT) {
265 return getFrameIndex(FI, VT, true);
267 SDValue getJumpTable(int JTI, MVT VT, bool isTarget = false);
268 SDValue getTargetJumpTable(int JTI, MVT VT) {
269 return getJumpTable(JTI, VT, true);
271 SDValue getConstantPool(Constant *C, MVT VT,
272 unsigned Align = 0, int Offs = 0, bool isT=false);
273 SDValue getTargetConstantPool(Constant *C, MVT VT,
274 unsigned Align = 0, int Offset = 0) {
275 return getConstantPool(C, VT, Align, Offset, true);
277 SDValue getConstantPool(MachineConstantPoolValue *C, MVT VT,
278 unsigned Align = 0, int Offs = 0, bool isT=false);
279 SDValue getTargetConstantPool(MachineConstantPoolValue *C,
280 MVT VT, unsigned Align = 0,
282 return getConstantPool(C, VT, Align, Offset, true);
284 SDValue getBasicBlock(MachineBasicBlock *MBB);
285 SDValue getExternalSymbol(const char *Sym, MVT VT);
286 SDValue getTargetExternalSymbol(const char *Sym, MVT VT);
287 SDValue getArgFlags(ISD::ArgFlagsTy Flags);
288 SDValue getValueType(MVT);
289 SDValue getRegister(unsigned Reg, MVT VT);
290 SDValue getDbgStopPoint(SDValue Root, unsigned Line, unsigned Col,
291 const CompileUnitDesc *CU);
292 SDValue getLabel(unsigned Opcode, SDValue Root, unsigned LabelID);
294 SDValue getCopyToReg(SDValue Chain, unsigned Reg, SDValue N) {
295 return getNode(ISD::CopyToReg, MVT::Other, Chain,
296 getRegister(Reg, N.getValueType()), N);
299 // This version of the getCopyToReg method takes an extra operand, which
300 // indicates that there is potentially an incoming flag value (if Flag is not
301 // null) and that there should be a flag result.
302 SDValue getCopyToReg(SDValue Chain, unsigned Reg, SDValue N,
304 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
305 SDValue Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Flag };
306 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.getNode() ? 4 : 3);
309 // Similar to last getCopyToReg() except parameter Reg is a SDValue
310 SDValue getCopyToReg(SDValue Chain, SDValue Reg, SDValue N,
312 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
313 SDValue Ops[] = { Chain, Reg, N, Flag };
314 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.getNode() ? 4 : 3);
317 SDValue getCopyFromReg(SDValue Chain, unsigned Reg, MVT VT) {
318 const MVT *VTs = getNodeValueTypes(VT, MVT::Other);
319 SDValue Ops[] = { Chain, getRegister(Reg, VT) };
320 return getNode(ISD::CopyFromReg, VTs, 2, Ops, 2);
323 // This version of the getCopyFromReg method takes an extra operand, which
324 // indicates that there is potentially an incoming flag value (if Flag is not
325 // null) and that there should be a flag result.
326 SDValue getCopyFromReg(SDValue Chain, unsigned Reg, MVT VT,
328 const MVT *VTs = getNodeValueTypes(VT, MVT::Other, MVT::Flag);
329 SDValue Ops[] = { Chain, getRegister(Reg, VT), Flag };
330 return getNode(ISD::CopyFromReg, VTs, 3, Ops, Flag.getNode() ? 3 : 2);
333 SDValue getCondCode(ISD::CondCode Cond);
335 /// getZeroExtendInReg - Return the expression required to zero extend the Op
336 /// value assuming it was the smaller SrcTy value.
337 SDValue getZeroExtendInReg(SDValue Op, MVT SrcTy);
339 /// getCALLSEQ_START - Return a new CALLSEQ_START node, which always must have
340 /// a flag result (to ensure it's not CSE'd).
341 SDValue getCALLSEQ_START(SDValue Chain, SDValue Op) {
342 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
343 SDValue Ops[] = { Chain, Op };
344 return getNode(ISD::CALLSEQ_START, VTs, 2, Ops, 2);
347 /// getCALLSEQ_END - Return a new CALLSEQ_END node, which always must have a
348 /// flag result (to ensure it's not CSE'd).
349 SDValue getCALLSEQ_END(SDValue Chain, SDValue Op1, SDValue Op2,
351 SDVTList NodeTys = getVTList(MVT::Other, MVT::Flag);
352 SmallVector<SDValue, 4> Ops;
353 Ops.push_back(Chain);
356 Ops.push_back(InFlag);
357 return getNode(ISD::CALLSEQ_END, NodeTys, &Ops[0],
358 (unsigned)Ops.size() - (InFlag.getNode() == 0 ? 1 : 0));
361 /// getNode - Gets or creates the specified node.
363 SDValue getNode(unsigned Opcode, MVT VT);
364 SDValue getNode(unsigned Opcode, MVT VT, SDValue N);
365 SDValue getNode(unsigned Opcode, MVT VT, SDValue N1, SDValue N2);
366 SDValue getNode(unsigned Opcode, MVT VT,
367 SDValue N1, SDValue N2, SDValue N3);
368 SDValue getNode(unsigned Opcode, MVT VT,
369 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
370 SDValue getNode(unsigned Opcode, MVT VT,
371 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
373 SDValue getNode(unsigned Opcode, MVT VT,
374 const SDValue *Ops, unsigned NumOps);
375 SDValue getNode(unsigned Opcode, MVT VT,
376 const SDUse *Ops, unsigned NumOps);
377 SDValue getNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
378 const SDValue *Ops, unsigned NumOps);
379 SDValue getNode(unsigned Opcode, const MVT *VTs, unsigned NumVTs,
380 const SDValue *Ops, unsigned NumOps);
381 SDValue getNode(unsigned Opcode, SDVTList VTs);
382 SDValue getNode(unsigned Opcode, SDVTList VTs, SDValue N);
383 SDValue getNode(unsigned Opcode, SDVTList VTs, SDValue N1, SDValue N2);
384 SDValue getNode(unsigned Opcode, SDVTList VTs,
385 SDValue N1, SDValue N2, SDValue N3);
386 SDValue getNode(unsigned Opcode, SDVTList VTs,
387 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
388 SDValue getNode(unsigned Opcode, SDVTList VTs,
389 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
391 SDValue getNode(unsigned Opcode, SDVTList VTs,
392 const SDValue *Ops, unsigned NumOps);
394 SDValue getMemcpy(SDValue Chain, SDValue Dst, SDValue Src,
395 SDValue Size, unsigned Align,
397 const Value *DstSV, uint64_t DstSVOff,
398 const Value *SrcSV, uint64_t SrcSVOff);
400 SDValue getMemmove(SDValue Chain, SDValue Dst, SDValue Src,
401 SDValue Size, unsigned Align,
402 const Value *DstSV, uint64_t DstOSVff,
403 const Value *SrcSV, uint64_t SrcSVOff);
405 SDValue getMemset(SDValue Chain, SDValue Dst, SDValue Src,
406 SDValue Size, unsigned Align,
407 const Value *DstSV, uint64_t DstSVOff);
409 /// getSetCC - Helper function to make it easier to build SetCC's if you just
410 /// have an ISD::CondCode instead of an SDValue.
412 SDValue getSetCC(MVT VT, SDValue LHS, SDValue RHS,
413 ISD::CondCode Cond) {
414 return getNode(ISD::SETCC, VT, LHS, RHS, getCondCode(Cond));
417 /// getVSetCC - Helper function to make it easier to build VSetCC's nodes
418 /// if you just have an ISD::CondCode instead of an SDValue.
420 SDValue getVSetCC(MVT VT, SDValue LHS, SDValue RHS,
421 ISD::CondCode Cond) {
422 return getNode(ISD::VSETCC, VT, LHS, RHS, getCondCode(Cond));
425 /// getSelectCC - Helper function to make it easier to build SelectCC's if you
426 /// just have an ISD::CondCode instead of an SDValue.
428 SDValue getSelectCC(SDValue LHS, SDValue RHS,
429 SDValue True, SDValue False, ISD::CondCode Cond) {
430 return getNode(ISD::SELECT_CC, True.getValueType(), LHS, RHS, True, False,
434 /// getVAArg - VAArg produces a result and token chain, and takes a pointer
435 /// and a source value as input.
436 SDValue getVAArg(MVT VT, SDValue Chain, SDValue Ptr,
439 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
441 SDValue getAtomic(unsigned Opcode, SDValue Chain, SDValue Ptr,
442 SDValue Cmp, SDValue Swp, const Value* PtrVal,
443 unsigned Alignment=0);
445 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
447 SDValue getAtomic(unsigned Opcode, SDValue Chain, SDValue Ptr,
448 SDValue Val, const Value* PtrVal,
449 unsigned Alignment = 0);
451 /// getMergeValues - Create a MERGE_VALUES node from the given operands.
452 /// Allowed to return something different (and simpler) if Simplify is true.
453 SDValue getMergeValues(const SDValue *Ops, unsigned NumOps,
454 bool Simplify = true);
456 /// getMergeValues - Create a MERGE_VALUES node from the given types and ops.
457 /// Allowed to return something different (and simpler) if Simplify is true.
458 /// May be faster than the above version if VTs is known and NumOps is large.
459 SDValue getMergeValues(SDVTList VTs, const SDValue *Ops, unsigned NumOps,
460 bool Simplify = true) {
461 if (Simplify && NumOps == 1)
463 return getNode(ISD::MERGE_VALUES, VTs, Ops, NumOps);
466 /// getCall - Create a CALL node from the given information.
468 SDValue getCall(unsigned CallingConv, bool IsVarArgs, bool IsTailCall,
469 SDVTList VTs, const SDValue *Operands, unsigned NumOperands);
471 /// getLoad - Loads are not normal binary operators: their result type is not
472 /// determined by their operands, and they produce a value AND a token chain.
474 SDValue getLoad(MVT VT, SDValue Chain, SDValue Ptr,
475 const Value *SV, int SVOffset, bool isVolatile=false,
476 unsigned Alignment=0);
477 SDValue getExtLoad(ISD::LoadExtType ExtType, MVT VT,
478 SDValue Chain, SDValue Ptr, const Value *SV,
479 int SVOffset, MVT EVT, bool isVolatile=false,
480 unsigned Alignment=0);
481 SDValue getIndexedLoad(SDValue OrigLoad, SDValue Base,
482 SDValue Offset, ISD::MemIndexedMode AM);
483 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
484 MVT VT, SDValue Chain,
485 SDValue Ptr, SDValue Offset,
486 const Value *SV, int SVOffset, MVT EVT,
487 bool isVolatile=false, unsigned Alignment=0);
489 /// getStore - Helper function to build ISD::STORE nodes.
491 SDValue getStore(SDValue Chain, SDValue Val, SDValue Ptr,
492 const Value *SV, int SVOffset, bool isVolatile=false,
493 unsigned Alignment=0);
494 SDValue getTruncStore(SDValue Chain, SDValue Val, SDValue Ptr,
495 const Value *SV, int SVOffset, MVT TVT,
496 bool isVolatile=false, unsigned Alignment=0);
497 SDValue getIndexedStore(SDValue OrigStoe, SDValue Base,
498 SDValue Offset, ISD::MemIndexedMode AM);
500 // getSrcValue - Construct a node to track a Value* through the backend.
501 SDValue getSrcValue(const Value *v);
503 // getMemOperand - Construct a node to track a memory reference
504 // through the backend.
505 SDValue getMemOperand(const MachineMemOperand &MO);
507 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the
508 /// specified operands. If the resultant node already exists in the DAG,
509 /// this does not modify the specified node, instead it returns the node that
510 /// already exists. If the resultant node does not exist in the DAG, the
511 /// input node is returned. As a degenerate case, if you specify the same
512 /// input operands as the node already has, the input node is returned.
513 SDValue UpdateNodeOperands(SDValue N, SDValue Op);
514 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2);
515 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
517 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
518 SDValue Op3, SDValue Op4);
519 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
520 SDValue Op3, SDValue Op4, SDValue Op5);
521 SDValue UpdateNodeOperands(SDValue N,
522 const SDValue *Ops, unsigned NumOps);
524 /// SelectNodeTo - These are used for target selectors to *mutate* the
525 /// specified node to have the specified return type, Target opcode, and
526 /// operands. Note that target opcodes are stored as
527 /// ~TargetOpcode in the node opcode field. The resultant node is returned.
528 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT);
529 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, SDValue Op1);
530 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
531 SDValue Op1, SDValue Op2);
532 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
533 SDValue Op1, SDValue Op2, SDValue Op3);
534 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
535 const SDValue *Ops, unsigned NumOps);
536 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, MVT VT2);
537 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
538 MVT VT2, const SDValue *Ops, unsigned NumOps);
539 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
540 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps);
541 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
542 MVT VT2, SDValue Op1);
543 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
544 MVT VT2, SDValue Op1, SDValue Op2);
545 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
546 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
547 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
548 const SDValue *Ops, unsigned NumOps);
550 /// MorphNodeTo - These *mutate* the specified node to have the specified
551 /// return type, opcode, and operands.
552 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT);
553 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT, SDValue Op1);
554 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
555 SDValue Op1, SDValue Op2);
556 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
557 SDValue Op1, SDValue Op2, SDValue Op3);
558 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
559 const SDValue *Ops, unsigned NumOps);
560 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1, MVT VT2);
561 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
562 MVT VT2, const SDValue *Ops, unsigned NumOps);
563 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
564 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps);
565 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
566 MVT VT2, SDValue Op1);
567 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
568 MVT VT2, SDValue Op1, SDValue Op2);
569 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
570 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
571 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
572 const SDValue *Ops, unsigned NumOps);
574 /// getTargetNode - These are used for target selectors to create a new node
575 /// with specified return type(s), target opcode, and operands.
577 /// Note that getTargetNode returns the resultant node. If there is already a
578 /// node of the specified opcode and operands, it returns that node instead of
580 SDNode *getTargetNode(unsigned Opcode, MVT VT);
581 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1);
582 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1, SDValue Op2);
583 SDNode *getTargetNode(unsigned Opcode, MVT VT,
584 SDValue Op1, SDValue Op2, SDValue Op3);
585 SDNode *getTargetNode(unsigned Opcode, MVT VT,
586 const SDValue *Ops, unsigned NumOps);
587 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2);
588 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, SDValue Op1);
589 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
590 MVT VT2, SDValue Op1, SDValue Op2);
591 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
592 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
593 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2,
594 const SDValue *Ops, unsigned NumOps);
595 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
596 SDValue Op1, SDValue Op2);
597 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
598 SDValue Op1, SDValue Op2, SDValue Op3);
599 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
600 const SDValue *Ops, unsigned NumOps);
601 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, MVT VT4,
602 const SDValue *Ops, unsigned NumOps);
603 SDNode *getTargetNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
604 const SDValue *Ops, unsigned NumOps);
606 /// getNodeIfExists - Get the specified node if it's already available, or
607 /// else return NULL.
608 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs,
609 const SDValue *Ops, unsigned NumOps);
611 /// DAGUpdateListener - Clients of various APIs that cause global effects on
612 /// the DAG can optionally implement this interface. This allows the clients
613 /// to handle the various sorts of updates that happen.
614 class DAGUpdateListener {
616 virtual ~DAGUpdateListener();
618 /// NodeDeleted - The node N that was deleted and, if E is not null, an
619 /// equivalent node E that replaced it.
620 virtual void NodeDeleted(SDNode *N, SDNode *E) = 0;
622 /// NodeUpdated - The node N that was updated.
623 virtual void NodeUpdated(SDNode *N) = 0;
626 /// RemoveDeadNode - Remove the specified node from the system. If any of its
627 /// operands then becomes dead, remove them as well. Inform UpdateListener
628 /// for each node deleted.
629 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0);
631 /// RemoveDeadNodes - This method deletes the unreachable nodes in the
632 /// given list, and any nodes that become unreachable as a result.
633 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes,
634 DAGUpdateListener *UpdateListener = 0);
636 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
637 /// This can cause recursive merging of nodes in the DAG. Use the first
638 /// version if 'From' is known to have a single result, use the second
639 /// if you have two nodes with identical results, use the third otherwise.
641 /// These methods all take an optional UpdateListener, which (if not null) is
642 /// informed about nodes that are deleted and modified due to recursive
643 /// changes in the dag.
645 void ReplaceAllUsesWith(SDValue From, SDValue Op,
646 DAGUpdateListener *UpdateListener = 0);
647 void ReplaceAllUsesWith(SDNode *From, SDNode *To,
648 DAGUpdateListener *UpdateListener = 0);
649 void ReplaceAllUsesWith(SDNode *From, const SDValue *To,
650 DAGUpdateListener *UpdateListener = 0);
652 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving
653 /// uses of other values produced by From.Val alone.
654 void ReplaceAllUsesOfValueWith(SDValue From, SDValue To,
655 DAGUpdateListener *UpdateListener = 0);
657 /// ReplaceAllUsesOfValuesWith - Like ReplaceAllUsesOfValueWith, but
658 /// for multiple values at once. This correctly handles the case where
659 /// there is an overlap between the From values and the To values.
660 void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To,
662 DAGUpdateListener *UpdateListener = 0);
664 /// AssignTopologicalOrder - Assign a unique node id for each node in the DAG
665 /// based on their topological order. It returns the maximum id and a vector
666 /// of the SDNodes* in assigned order by reference.
667 unsigned AssignTopologicalOrder(std::vector<SDNode*> &TopOrder);
669 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary
671 static bool isCommutativeBinOp(unsigned Opcode) {
672 // FIXME: This should get its info from the td file, so that we can include
687 case ISD::ADDE: return true;
688 default: return false;
694 /// CreateStackTemporary - Create a stack temporary, suitable for holding the
695 /// specified value type. If minAlign is specified, the slot size will have
696 /// at least that alignment.
697 SDValue CreateStackTemporary(MVT VT, unsigned minAlign = 1);
699 /// FoldSetCC - Constant fold a setcc to true or false.
700 SDValue FoldSetCC(MVT VT, SDValue N1,
701 SDValue N2, ISD::CondCode Cond);
703 /// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We
704 /// use this predicate to simplify operations downstream.
705 bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const;
707 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We
708 /// use this predicate to simplify operations downstream. Op and Mask are
709 /// known to be the same type.
710 bool MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth = 0)
713 /// ComputeMaskedBits - Determine which of the bits specified in Mask are
714 /// known to be either zero or one and return them in the KnownZero/KnownOne
715 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit
716 /// processing. Targets can implement the computeMaskedBitsForTargetNode
717 /// method in the TargetLowering class to allow target nodes to be understood.
718 void ComputeMaskedBits(SDValue Op, const APInt &Mask, APInt &KnownZero,
719 APInt &KnownOne, unsigned Depth = 0) const;
721 /// ComputeNumSignBits - Return the number of times the sign bit of the
722 /// register is replicated into the other bits. We know that at least 1 bit
723 /// is always equal to the sign bit (itself), but other cases can give us
724 /// information. For example, immediately after an "SRA X, 2", we know that
725 /// the top 3 bits are all equal to each other, so we return 3. Targets can
726 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
727 /// class to allow target nodes to be understood.
728 unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const;
730 /// isVerifiedDebugInfoDesc - Returns true if the specified SDValue has
731 /// been verified as a debug information descriptor.
732 bool isVerifiedDebugInfoDesc(SDValue Op) const;
734 /// getShuffleScalarElt - Returns the scalar element that will make up the ith
735 /// element of the result of the vector shuffle.
736 SDValue getShuffleScalarElt(const SDNode *N, unsigned Idx);
739 bool RemoveNodeFromCSEMaps(SDNode *N);
740 SDNode *AddNonLeafNodeToCSEMaps(SDNode *N);
741 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos);
742 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2,
744 SDNode *FindModifiedNodeSlot(SDNode *N, const SDValue *Ops, unsigned NumOps,
747 void DeleteNodeNotInCSEMaps(SDNode *N);
749 unsigned getMVTAlignment(MVT MemoryVT) const;
751 void allnodes_clear();
753 // List of non-single value types.
754 std::vector<SDVTList> VTList;
756 // Maps to auto-CSE operations.
757 std::vector<CondCodeSDNode*> CondCodeNodes;
759 std::vector<SDNode*> ValueTypeNodes;
760 std::map<MVT, SDNode*, MVT::compareRawBits> ExtendedValueTypeNodes;
761 StringMap<SDNode*> ExternalSymbols;
762 StringMap<SDNode*> TargetExternalSymbols;
765 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
766 typedef SelectionDAG::allnodes_iterator nodes_iterator;
767 static nodes_iterator nodes_begin(SelectionDAG *G) {
768 return G->allnodes_begin();
770 static nodes_iterator nodes_end(SelectionDAG *G) {
771 return G->allnodes_end();
775 } // end namespace llvm