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/DenseSet.h"
20 #include "llvm/ADT/FoldingSet.h"
21 #include "llvm/ADT/StringMap.h"
22 #include "llvm/CodeGen/SelectionDAGNodes.h"
34 class MachineModuleInfo;
36 class MachineFunction;
37 class MachineConstantPoolValue;
38 class FunctionLoweringInfo;
40 template<> struct ilist_traits<SDNode> : public ilist_default_traits<SDNode> {
42 mutable SDNode Sentinel;
44 ilist_traits() : Sentinel(ISD::DELETED_NODE, SDVTList()) {}
46 SDNode *createSentinel() const {
49 static void destroySentinel(SDNode *) {}
51 static void deleteNode(SDNode *) {
52 assert(0 && "ilist_traits<SDNode> shouldn't see a deleteNode call!");
55 static void createNode(const SDNode &);
59 Unrestricted, // Combine may create illegal operations and illegal types.
60 NoIllegalTypes, // Combine may create illegal operations but no illegal types.
61 NoIllegalOperations // Combine may only create legal operations and types.
64 /// SelectionDAG class - This is used to represent a portion of an LLVM function
65 /// in a low-level Data Dependence DAG representation suitable for instruction
66 /// selection. This DAG is constructed as the first step of instruction
67 /// selection in order to allow implementation of machine specific optimizations
68 /// and code simplifications.
70 /// The representation used by the SelectionDAG is a target-independent
71 /// representation, which has some similarities to the GCC RTL representation,
72 /// but is significantly more simple, powerful, and is a graph form instead of a
78 FunctionLoweringInfo &FLI;
79 MachineModuleInfo *MMI;
82 /// EntryNode - The starting token.
85 /// Root - The root of the entire DAG.
88 /// AllNodes - A linked list of nodes in the current DAG.
89 ilist<SDNode> AllNodes;
91 /// NodeAllocatorType - The AllocatorType for allocating SDNodes. We use
92 /// pool allocation with recycling.
93 typedef RecyclingAllocator<BumpPtrAllocator, SDNode, sizeof(LargestSDNode),
94 AlignOf<MostAlignedSDNode>::Alignment>
97 /// NodeAllocator - Pool allocation for nodes.
98 NodeAllocatorType NodeAllocator;
100 /// CSEMap - This structure is used to memoize nodes, automatically performing
101 /// CSE with existing nodes with a duplicate is requested.
102 FoldingSet<SDNode> CSEMap;
104 /// OperandAllocator - Pool allocation for machine-opcode SDNode operands.
105 BumpPtrAllocator OperandAllocator;
107 /// Allocator - Pool allocation for misc. objects that are created once per
109 BumpPtrAllocator Allocator;
111 /// VerifyNode - Sanity check the given node. Aborts if it is invalid.
112 void VerifyNode(SDNode *N);
114 /// setGraphColorHelper - Implementation of setSubgraphColor.
115 /// Return whether we had to truncate the search.
117 bool setSubgraphColorHelper(SDNode *N, const char *Color, DenseSet<SDNode *> &visited,
118 int level, bool &printed);
121 SelectionDAG(TargetLowering &tli, FunctionLoweringInfo &fli);
124 /// init - Prepare this SelectionDAG to process code in the given
127 void init(MachineFunction &mf, MachineModuleInfo *mmi, DwarfWriter *dw);
129 /// clear - Clear state and free memory necessary to make this
130 /// SelectionDAG ready to process a new block.
134 MachineFunction &getMachineFunction() const { return *MF; }
135 const TargetMachine &getTarget() const;
136 TargetLowering &getTargetLoweringInfo() const { return TLI; }
137 FunctionLoweringInfo &getFunctionLoweringInfo() const { return FLI; }
138 MachineModuleInfo *getMachineModuleInfo() const { return MMI; }
139 DwarfWriter *getDwarfWriter() const { return DW; }
141 /// viewGraph - Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
143 void viewGraph(const std::string &Title);
147 std::map<const SDNode *, std::string> NodeGraphAttrs;
150 /// clearGraphAttrs - Clear all previously defined node graph attributes.
151 /// Intended to be used from a debugging tool (eg. gdb).
152 void clearGraphAttrs();
154 /// setGraphAttrs - Set graph attributes for a node. (eg. "color=red".)
156 void setGraphAttrs(const SDNode *N, const char *Attrs);
158 /// getGraphAttrs - Get graph attributes for a node. (eg. "color=red".)
159 /// Used from getNodeAttributes.
160 const std::string getGraphAttrs(const SDNode *N) const;
162 /// setGraphColor - Convenience for setting node color attribute.
164 void setGraphColor(const SDNode *N, const char *Color);
166 /// setGraphColor - Convenience for setting subgraph color attribute.
168 void setSubgraphColor(SDNode *N, const char *Color);
170 typedef ilist<SDNode>::const_iterator allnodes_const_iterator;
171 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
172 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
173 typedef ilist<SDNode>::iterator allnodes_iterator;
174 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
175 allnodes_iterator allnodes_end() { return AllNodes.end(); }
176 ilist<SDNode>::size_type allnodes_size() const {
177 return AllNodes.size();
180 /// getRoot - Return the root tag of the SelectionDAG.
182 const SDValue &getRoot() const { return Root; }
184 /// getEntryNode - Return the token chain corresponding to the entry of the
186 SDValue getEntryNode() const {
187 return SDValue(const_cast<SDNode *>(&EntryNode), 0);
190 /// setRoot - Set the current root tag of the SelectionDAG.
192 const SDValue &setRoot(SDValue N) {
193 assert((!N.getNode() || N.getValueType() == MVT::Other) &&
194 "DAG root value is not a chain!");
198 /// Combine - This iterates over the nodes in the SelectionDAG, folding
199 /// certain types of nodes together, or eliminating superfluous nodes. The
200 /// Level argument controls whether Combine is allowed to produce nodes and
201 /// types that are illegal on the target.
202 void Combine(CombineLevel Level, AliasAnalysis &AA, bool Fast);
204 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that
205 /// only uses types natively supported by the target. Returns "true" if it
206 /// made any changes.
208 /// Note that this is an involved process that may invalidate pointers into
210 bool LegalizeTypes();
212 /// Legalize - This transforms the SelectionDAG into a SelectionDAG that is
213 /// compatible with the target instruction selector, as indicated by the
214 /// TargetLowering object.
216 /// Note that this is an involved process that may invalidate pointers into
218 void Legalize(bool TypesNeedLegalizing);
220 /// RemoveDeadNodes - This method deletes all unreachable nodes in the
222 void RemoveDeadNodes();
224 /// DeleteNode - Remove the specified node from the system. This node must
225 /// have no referrers.
226 void DeleteNode(SDNode *N);
228 /// getVTList - Return an SDVTList that represents the list of values
230 SDVTList getVTList(MVT VT);
231 SDVTList getVTList(MVT VT1, MVT VT2);
232 SDVTList getVTList(MVT VT1, MVT VT2, MVT VT3);
233 SDVTList getVTList(MVT VT1, MVT VT2, MVT VT3, MVT VT4);
234 SDVTList getVTList(const MVT *VTs, unsigned NumVTs);
236 /// getNodeValueTypes - These are obsolete, use getVTList instead.
237 const MVT *getNodeValueTypes(MVT VT) {
238 return getVTList(VT).VTs;
240 const MVT *getNodeValueTypes(MVT VT1, MVT VT2) {
241 return getVTList(VT1, VT2).VTs;
243 const MVT *getNodeValueTypes(MVT VT1, MVT VT2, MVT VT3) {
244 return getVTList(VT1, VT2, VT3).VTs;
246 const MVT *getNodeValueTypes(MVT VT1, MVT VT2, MVT VT3, MVT VT4) {
247 return getVTList(VT1, VT2, VT3, VT4).VTs;
249 const MVT *getNodeValueTypes(const std::vector<MVT> &vtList) {
250 return getVTList(&vtList[0], (unsigned)vtList.size()).VTs;
254 //===--------------------------------------------------------------------===//
255 // Node creation methods.
257 SDValue getConstant(uint64_t Val, MVT VT, bool isTarget = false);
258 SDValue getConstant(const APInt &Val, MVT VT, bool isTarget = false);
259 SDValue getConstant(const ConstantInt &Val, MVT VT, bool isTarget = false);
260 SDValue getIntPtrConstant(uint64_t Val, bool isTarget = false);
261 SDValue getTargetConstant(uint64_t Val, MVT VT) {
262 return getConstant(Val, VT, true);
264 SDValue getTargetConstant(const APInt &Val, MVT VT) {
265 return getConstant(Val, VT, true);
267 SDValue getTargetConstant(const ConstantInt &Val, MVT VT) {
268 return getConstant(Val, VT, true);
270 SDValue getConstantFP(double Val, MVT VT, bool isTarget = false);
271 SDValue getConstantFP(const APFloat& Val, MVT VT, bool isTarget = false);
272 SDValue getConstantFP(const ConstantFP &CF, MVT VT, bool isTarget = false);
273 SDValue getTargetConstantFP(double Val, MVT VT) {
274 return getConstantFP(Val, VT, true);
276 SDValue getTargetConstantFP(const APFloat& Val, MVT VT) {
277 return getConstantFP(Val, VT, true);
279 SDValue getTargetConstantFP(const ConstantFP &Val, MVT VT) {
280 return getConstantFP(Val, VT, true);
282 SDValue getGlobalAddress(const GlobalValue *GV, MVT VT,
283 int64_t offset = 0, bool isTargetGA = false);
284 SDValue getTargetGlobalAddress(const GlobalValue *GV, MVT VT,
285 int64_t offset = 0) {
286 return getGlobalAddress(GV, VT, offset, true);
288 SDValue getFrameIndex(int FI, MVT VT, bool isTarget = false);
289 SDValue getTargetFrameIndex(int FI, MVT VT) {
290 return getFrameIndex(FI, VT, true);
292 SDValue getJumpTable(int JTI, MVT VT, bool isTarget = false);
293 SDValue getTargetJumpTable(int JTI, MVT VT) {
294 return getJumpTable(JTI, VT, true);
296 SDValue getConstantPool(Constant *C, MVT VT,
297 unsigned Align = 0, int Offs = 0, bool isT=false);
298 SDValue getTargetConstantPool(Constant *C, MVT VT,
299 unsigned Align = 0, int Offset = 0) {
300 return getConstantPool(C, VT, Align, Offset, true);
302 SDValue getConstantPool(MachineConstantPoolValue *C, MVT VT,
303 unsigned Align = 0, int Offs = 0, bool isT=false);
304 SDValue getTargetConstantPool(MachineConstantPoolValue *C,
305 MVT VT, unsigned Align = 0,
307 return getConstantPool(C, VT, Align, Offset, true);
309 SDValue getBasicBlock(MachineBasicBlock *MBB);
310 SDValue getExternalSymbol(const char *Sym, MVT VT);
311 SDValue getTargetExternalSymbol(const char *Sym, MVT VT);
312 SDValue getArgFlags(ISD::ArgFlagsTy Flags);
313 SDValue getValueType(MVT);
314 SDValue getRegister(unsigned Reg, MVT VT);
315 SDValue getDbgStopPoint(SDValue Root, unsigned Line, unsigned Col,
317 SDValue getLabel(unsigned Opcode, SDValue Root, unsigned LabelID);
319 SDValue getCopyToReg(SDValue Chain, unsigned Reg, SDValue N) {
320 return getNode(ISD::CopyToReg, MVT::Other, Chain,
321 getRegister(Reg, N.getValueType()), N);
324 // This version of the getCopyToReg method takes an extra operand, which
325 // indicates that there is potentially an incoming flag value (if Flag is not
326 // null) and that there should be a flag result.
327 SDValue getCopyToReg(SDValue Chain, unsigned Reg, SDValue N,
329 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
330 SDValue Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Flag };
331 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.getNode() ? 4 : 3);
334 // Similar to last getCopyToReg() except parameter Reg is a SDValue
335 SDValue getCopyToReg(SDValue Chain, SDValue Reg, SDValue N,
337 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
338 SDValue Ops[] = { Chain, Reg, N, Flag };
339 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.getNode() ? 4 : 3);
342 SDValue getCopyFromReg(SDValue Chain, unsigned Reg, MVT VT) {
343 const MVT *VTs = getNodeValueTypes(VT, MVT::Other);
344 SDValue Ops[] = { Chain, getRegister(Reg, VT) };
345 return getNode(ISD::CopyFromReg, VTs, 2, Ops, 2);
348 // This version of the getCopyFromReg method takes an extra operand, which
349 // indicates that there is potentially an incoming flag value (if Flag is not
350 // null) and that there should be a flag result.
351 SDValue getCopyFromReg(SDValue Chain, unsigned Reg, MVT VT,
353 const MVT *VTs = getNodeValueTypes(VT, MVT::Other, MVT::Flag);
354 SDValue Ops[] = { Chain, getRegister(Reg, VT), Flag };
355 return getNode(ISD::CopyFromReg, VTs, 3, Ops, Flag.getNode() ? 3 : 2);
358 SDValue getCondCode(ISD::CondCode Cond);
360 /// Returns the ConvertRndSat Note: Avoid using this node because it may
361 /// disappear in the future and most targets don't support it.
362 SDValue getConvertRndSat(MVT VT, SDValue Val, SDValue DTy, SDValue STy,
363 SDValue Rnd, SDValue Sat, ISD::CvtCode Code);
365 /// getZeroExtendInReg - Return the expression required to zero extend the Op
366 /// value assuming it was the smaller SrcTy value.
367 SDValue getZeroExtendInReg(SDValue Op, MVT SrcTy);
369 /// getNOT - Create a bitwise NOT operation as (XOR Val, -1).
370 SDValue getNOT(SDValue Val, MVT VT);
372 /// getCALLSEQ_START - Return a new CALLSEQ_START node, which always must have
373 /// a flag result (to ensure it's not CSE'd).
374 SDValue getCALLSEQ_START(SDValue Chain, SDValue Op) {
375 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
376 SDValue Ops[] = { Chain, Op };
377 return getNode(ISD::CALLSEQ_START, VTs, 2, Ops, 2);
380 /// getCALLSEQ_END - Return a new CALLSEQ_END node, which always must have a
381 /// flag result (to ensure it's not CSE'd).
382 SDValue getCALLSEQ_END(SDValue Chain, SDValue Op1, SDValue Op2,
384 SDVTList NodeTys = getVTList(MVT::Other, MVT::Flag);
385 SmallVector<SDValue, 4> Ops;
386 Ops.push_back(Chain);
389 Ops.push_back(InFlag);
390 return getNode(ISD::CALLSEQ_END, NodeTys, &Ops[0],
391 (unsigned)Ops.size() - (InFlag.getNode() == 0 ? 1 : 0));
394 /// getNode - Gets or creates the specified node.
396 SDValue getNode(unsigned Opcode, MVT VT);
397 SDValue getNode(unsigned Opcode, MVT VT, SDValue N);
398 SDValue getNode(unsigned Opcode, MVT VT, SDValue N1, SDValue N2);
399 SDValue getNode(unsigned Opcode, MVT VT,
400 SDValue N1, SDValue N2, SDValue N3);
401 SDValue getNode(unsigned Opcode, MVT VT,
402 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
403 SDValue getNode(unsigned Opcode, MVT VT,
404 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
406 SDValue getNode(unsigned Opcode, MVT VT,
407 const SDValue *Ops, unsigned NumOps);
408 SDValue getNode(unsigned Opcode, MVT VT,
409 const SDUse *Ops, unsigned NumOps);
410 SDValue getNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
411 const SDValue *Ops, unsigned NumOps);
412 SDValue getNode(unsigned Opcode, const MVT *VTs, unsigned NumVTs,
413 const SDValue *Ops, unsigned NumOps);
414 SDValue getNode(unsigned Opcode, SDVTList VTs);
415 SDValue getNode(unsigned Opcode, SDVTList VTs, SDValue N);
416 SDValue getNode(unsigned Opcode, SDVTList VTs, SDValue N1, SDValue N2);
417 SDValue getNode(unsigned Opcode, SDVTList VTs,
418 SDValue N1, SDValue N2, SDValue N3);
419 SDValue getNode(unsigned Opcode, SDVTList VTs,
420 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
421 SDValue getNode(unsigned Opcode, SDVTList VTs,
422 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
424 SDValue getNode(unsigned Opcode, SDVTList VTs,
425 const SDValue *Ops, unsigned NumOps);
427 SDValue getMemcpy(SDValue Chain, SDValue Dst, SDValue Src,
428 SDValue Size, unsigned Align, bool AlwaysInline,
429 const Value *DstSV, uint64_t DstSVOff,
430 const Value *SrcSV, uint64_t SrcSVOff);
432 SDValue getMemmove(SDValue Chain, SDValue Dst, SDValue Src,
433 SDValue Size, unsigned Align,
434 const Value *DstSV, uint64_t DstOSVff,
435 const Value *SrcSV, uint64_t SrcSVOff);
437 SDValue getMemset(SDValue Chain, SDValue Dst, SDValue Src,
438 SDValue Size, unsigned Align,
439 const Value *DstSV, uint64_t DstSVOff);
441 /// getSetCC - Helper function to make it easier to build SetCC's if you just
442 /// have an ISD::CondCode instead of an SDValue.
444 SDValue getSetCC(MVT VT, SDValue LHS, SDValue RHS,
445 ISD::CondCode Cond) {
446 return getNode(ISD::SETCC, VT, LHS, RHS, getCondCode(Cond));
449 /// getVSetCC - Helper function to make it easier to build VSetCC's nodes
450 /// if you just have an ISD::CondCode instead of an SDValue.
452 SDValue getVSetCC(MVT VT, SDValue LHS, SDValue RHS,
453 ISD::CondCode Cond) {
454 return getNode(ISD::VSETCC, VT, LHS, RHS, getCondCode(Cond));
457 /// getSelectCC - Helper function to make it easier to build SelectCC's if you
458 /// just have an ISD::CondCode instead of an SDValue.
460 SDValue getSelectCC(SDValue LHS, SDValue RHS,
461 SDValue True, SDValue False, ISD::CondCode Cond) {
462 return getNode(ISD::SELECT_CC, True.getValueType(), LHS, RHS, True, False,
466 /// getVAArg - VAArg produces a result and token chain, and takes a pointer
467 /// and a source value as input.
468 SDValue getVAArg(MVT VT, SDValue Chain, SDValue Ptr,
471 /// getAtomic - Gets a node for an atomic op, produces result and chain and
473 SDValue getAtomic(unsigned Opcode, MVT MemVT, SDValue Chain, SDValue Ptr,
474 SDValue Cmp, SDValue Swp, const Value* PtrVal,
475 unsigned Alignment=0);
477 /// getAtomic - Gets a node for an atomic op, produces result and chain and
478 /// takes 2 operands.
479 SDValue getAtomic(unsigned Opcode, MVT MemVT, SDValue Chain, SDValue Ptr,
480 SDValue Val, const Value* PtrVal,
481 unsigned Alignment = 0);
483 /// getMemIntrinsicNode - Creates a MemIntrinsicNode that may produce a
484 /// result and takes a list of operands.
485 SDValue getMemIntrinsicNode(unsigned Opcode,
486 const MVT *VTs, unsigned NumVTs,
487 const SDValue *Ops, unsigned NumOps,
488 MVT MemVT, const Value *srcValue, int SVOff,
489 unsigned Align = 0, bool Vol = false,
490 bool ReadMem = true, bool WriteMem = true);
492 SDValue getMemIntrinsicNode(unsigned Opcode, SDVTList VTList,
493 const SDValue *Ops, unsigned NumOps,
494 MVT MemVT, const Value *srcValue, int SVOff,
495 unsigned Align = 0, bool Vol = false,
496 bool ReadMem = true, bool WriteMem = true);
498 /// getMergeValues - Create a MERGE_VALUES node from the given operands.
499 SDValue getMergeValues(const SDValue *Ops, unsigned NumOps);
501 /// getCall - Create a CALL node from the given information.
503 SDValue getCall(unsigned CallingConv, bool IsVarArgs, bool IsTailCall,
504 bool isInreg, SDVTList VTs, const SDValue *Operands,
505 unsigned NumOperands);
507 /// getLoad - Loads are not normal binary operators: their result type is not
508 /// determined by their operands, and they produce a value AND a token chain.
510 SDValue getLoad(MVT VT, SDValue Chain, SDValue Ptr,
511 const Value *SV, int SVOffset, bool isVolatile=false,
512 unsigned Alignment=0);
513 SDValue getExtLoad(ISD::LoadExtType ExtType, MVT VT,
514 SDValue Chain, SDValue Ptr, const Value *SV,
515 int SVOffset, MVT EVT, bool isVolatile=false,
516 unsigned Alignment=0);
517 SDValue getIndexedLoad(SDValue OrigLoad, SDValue Base,
518 SDValue Offset, ISD::MemIndexedMode AM);
519 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
520 MVT VT, SDValue Chain,
521 SDValue Ptr, SDValue Offset,
522 const Value *SV, int SVOffset, MVT EVT,
523 bool isVolatile=false, unsigned Alignment=0);
525 /// getStore - Helper function to build ISD::STORE nodes.
527 SDValue getStore(SDValue Chain, SDValue Val, SDValue Ptr,
528 const Value *SV, int SVOffset, bool isVolatile=false,
529 unsigned Alignment=0);
530 SDValue getTruncStore(SDValue Chain, SDValue Val, SDValue Ptr,
531 const Value *SV, int SVOffset, MVT TVT,
532 bool isVolatile=false, unsigned Alignment=0);
533 SDValue getIndexedStore(SDValue OrigStoe, SDValue Base,
534 SDValue Offset, ISD::MemIndexedMode AM);
536 // getSrcValue - Construct a node to track a Value* through the backend.
537 SDValue getSrcValue(const Value *v);
539 // getMemOperand - Construct a node to track a memory reference
540 // through the backend.
541 SDValue getMemOperand(const MachineMemOperand &MO);
543 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the
544 /// specified operands. If the resultant node already exists in the DAG,
545 /// this does not modify the specified node, instead it returns the node that
546 /// already exists. If the resultant node does not exist in the DAG, the
547 /// input node is returned. As a degenerate case, if you specify the same
548 /// input operands as the node already has, the input node is returned.
549 SDValue UpdateNodeOperands(SDValue N, SDValue Op);
550 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2);
551 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
553 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
554 SDValue Op3, SDValue Op4);
555 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
556 SDValue Op3, SDValue Op4, SDValue Op5);
557 SDValue UpdateNodeOperands(SDValue N,
558 const SDValue *Ops, unsigned NumOps);
560 /// SelectNodeTo - These are used for target selectors to *mutate* the
561 /// specified node to have the specified return type, Target opcode, and
562 /// operands. Note that target opcodes are stored as
563 /// ~TargetOpcode in the node opcode field. The resultant node is returned.
564 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT);
565 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, SDValue Op1);
566 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
567 SDValue Op1, SDValue Op2);
568 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
569 SDValue Op1, SDValue Op2, SDValue Op3);
570 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
571 const SDValue *Ops, unsigned NumOps);
572 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, MVT VT2);
573 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
574 MVT VT2, const SDValue *Ops, unsigned NumOps);
575 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
576 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps);
577 SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, MVT VT1,
578 MVT VT2, MVT VT3, MVT VT4, const SDValue *Ops,
580 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
581 MVT VT2, SDValue Op1);
582 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
583 MVT VT2, SDValue Op1, SDValue Op2);
584 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
585 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
586 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
587 MVT VT2, MVT VT3, SDValue Op1, SDValue Op2, SDValue Op3);
588 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
589 const SDValue *Ops, unsigned NumOps);
591 /// MorphNodeTo - These *mutate* the specified node to have the specified
592 /// return type, opcode, and operands.
593 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT);
594 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT, SDValue Op1);
595 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
596 SDValue Op1, SDValue Op2);
597 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
598 SDValue Op1, SDValue Op2, SDValue Op3);
599 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
600 const SDValue *Ops, unsigned NumOps);
601 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1, MVT VT2);
602 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
603 MVT VT2, const SDValue *Ops, unsigned NumOps);
604 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
605 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps);
606 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
607 MVT VT2, SDValue Op1);
608 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
609 MVT VT2, SDValue Op1, SDValue Op2);
610 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
611 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
612 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
613 const SDValue *Ops, unsigned NumOps);
615 /// getTargetNode - These are used for target selectors to create a new node
616 /// with specified return type(s), target opcode, and operands.
618 /// Note that getTargetNode returns the resultant node. If there is already a
619 /// node of the specified opcode and operands, it returns that node instead of
621 SDNode *getTargetNode(unsigned Opcode, MVT VT);
622 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1);
623 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1, SDValue Op2);
624 SDNode *getTargetNode(unsigned Opcode, MVT VT,
625 SDValue Op1, SDValue Op2, SDValue Op3);
626 SDNode *getTargetNode(unsigned Opcode, MVT VT,
627 const SDValue *Ops, unsigned NumOps);
628 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2);
629 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, SDValue Op1);
630 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
631 MVT VT2, SDValue Op1, SDValue Op2);
632 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
633 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
634 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2,
635 const SDValue *Ops, unsigned NumOps);
636 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
637 SDValue Op1, SDValue Op2);
638 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
639 SDValue Op1, SDValue Op2, SDValue Op3);
640 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
641 const SDValue *Ops, unsigned NumOps);
642 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, MVT VT4,
643 const SDValue *Ops, unsigned NumOps);
644 SDNode *getTargetNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
645 const SDValue *Ops, unsigned NumOps);
647 /// getNodeIfExists - Get the specified node if it's already available, or
648 /// else return NULL.
649 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs,
650 const SDValue *Ops, unsigned NumOps);
652 /// DAGUpdateListener - Clients of various APIs that cause global effects on
653 /// the DAG can optionally implement this interface. This allows the clients
654 /// to handle the various sorts of updates that happen.
655 class DAGUpdateListener {
657 virtual ~DAGUpdateListener();
659 /// NodeDeleted - The node N that was deleted and, if E is not null, an
660 /// equivalent node E that replaced it.
661 virtual void NodeDeleted(SDNode *N, SDNode *E) = 0;
663 /// NodeUpdated - The node N that was updated.
664 virtual void NodeUpdated(SDNode *N) = 0;
667 /// RemoveDeadNode - Remove the specified node from the system. If any of its
668 /// operands then becomes dead, remove them as well. Inform UpdateListener
669 /// for each node deleted.
670 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0);
672 /// RemoveDeadNodes - This method deletes the unreachable nodes in the
673 /// given list, and any nodes that become unreachable as a result.
674 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes,
675 DAGUpdateListener *UpdateListener = 0);
677 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
678 /// This can cause recursive merging of nodes in the DAG. Use the first
679 /// version if 'From' is known to have a single result, use the second
680 /// if you have two nodes with identical results, use the third otherwise.
682 /// These methods all take an optional UpdateListener, which (if not null) is
683 /// informed about nodes that are deleted and modified due to recursive
684 /// changes in the dag.
686 /// These functions only replace all existing uses. It's possible that as
687 /// these replacements are being performed, CSE may cause the From node
688 /// to be given new uses. These new uses of From are left in place, and
689 /// not automatically transfered to To.
691 void ReplaceAllUsesWith(SDValue From, SDValue Op,
692 DAGUpdateListener *UpdateListener = 0);
693 void ReplaceAllUsesWith(SDNode *From, SDNode *To,
694 DAGUpdateListener *UpdateListener = 0);
695 void ReplaceAllUsesWith(SDNode *From, const SDValue *To,
696 DAGUpdateListener *UpdateListener = 0);
698 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving
699 /// uses of other values produced by From.Val alone.
700 void ReplaceAllUsesOfValueWith(SDValue From, SDValue To,
701 DAGUpdateListener *UpdateListener = 0);
703 /// ReplaceAllUsesOfValuesWith - Like ReplaceAllUsesOfValueWith, but
704 /// for multiple values at once. This correctly handles the case where
705 /// there is an overlap between the From values and the To values.
706 void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To,
708 DAGUpdateListener *UpdateListener = 0);
710 /// AssignTopologicalOrder - Topological-sort the AllNodes list and a
711 /// assign a unique node id for each node in the DAG based on their
712 /// topological order. Returns the number of nodes.
713 unsigned AssignTopologicalOrder();
715 /// RepositionNode - Move node N in the AllNodes list to be immediately
716 /// before the given iterator Position. This may be used to update the
717 /// topological ordering when the list of nodes is modified.
718 void RepositionNode(allnodes_iterator Position, SDNode *N) {
719 AllNodes.insert(Position, AllNodes.remove(N));
722 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary
724 static bool isCommutativeBinOp(unsigned Opcode) {
725 // FIXME: This should get its info from the td file, so that we can include
740 case ISD::ADDE: return true;
741 default: return false;
747 /// CreateStackTemporary - Create a stack temporary, suitable for holding the
748 /// specified value type. If minAlign is specified, the slot size will have
749 /// at least that alignment.
750 SDValue CreateStackTemporary(MVT VT, unsigned minAlign = 1);
752 /// CreateStackTemporary - Create a stack temporary suitable for holding
753 /// either of the specified value types.
754 SDValue CreateStackTemporary(MVT VT1, MVT VT2);
756 /// FoldConstantArithmetic -
757 SDValue FoldConstantArithmetic(unsigned Opcode,
759 ConstantSDNode *Cst1,
760 ConstantSDNode *Cst2);
762 /// FoldSetCC - Constant fold a setcc to true or false.
763 SDValue FoldSetCC(MVT VT, SDValue N1,
764 SDValue N2, ISD::CondCode Cond);
766 /// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We
767 /// use this predicate to simplify operations downstream.
768 bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const;
770 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We
771 /// use this predicate to simplify operations downstream. Op and Mask are
772 /// known to be the same type.
773 bool MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth = 0)
776 /// ComputeMaskedBits - Determine which of the bits specified in Mask are
777 /// known to be either zero or one and return them in the KnownZero/KnownOne
778 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit
779 /// processing. Targets can implement the computeMaskedBitsForTargetNode
780 /// method in the TargetLowering class to allow target nodes to be understood.
781 void ComputeMaskedBits(SDValue Op, const APInt &Mask, APInt &KnownZero,
782 APInt &KnownOne, unsigned Depth = 0) const;
784 /// ComputeNumSignBits - Return the number of times the sign bit of the
785 /// register is replicated into the other bits. We know that at least 1 bit
786 /// is always equal to the sign bit (itself), but other cases can give us
787 /// information. For example, immediately after an "SRA X, 2", we know that
788 /// the top 3 bits are all equal to each other, so we return 3. Targets can
789 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
790 /// class to allow target nodes to be understood.
791 unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const;
793 /// isVerifiedDebugInfoDesc - Returns true if the specified SDValue has
794 /// been verified as a debug information descriptor.
795 bool isVerifiedDebugInfoDesc(SDValue Op) const;
797 /// getShuffleScalarElt - Returns the scalar element that will make up the ith
798 /// element of the result of the vector shuffle.
799 SDValue getShuffleScalarElt(const SDNode *N, unsigned Idx);
802 bool RemoveNodeFromCSEMaps(SDNode *N);
803 void AddModifiedNodeToCSEMaps(SDNode *N, DAGUpdateListener *UpdateListener);
804 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos);
805 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2,
807 SDNode *FindModifiedNodeSlot(SDNode *N, const SDValue *Ops, unsigned NumOps,
810 void DeleteNodeNotInCSEMaps(SDNode *N);
811 void DeallocateNode(SDNode *N);
813 unsigned getMVTAlignment(MVT MemoryVT) const;
815 void allnodes_clear();
817 // List of non-single value types.
818 std::vector<SDVTList> VTList;
820 // Maps to auto-CSE operations.
821 std::vector<CondCodeSDNode*> CondCodeNodes;
823 std::vector<SDNode*> ValueTypeNodes;
824 std::map<MVT, SDNode*, MVT::compareRawBits> ExtendedValueTypeNodes;
825 StringMap<SDNode*> ExternalSymbols;
826 StringMap<SDNode*> TargetExternalSymbols;
829 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
830 typedef SelectionDAG::allnodes_iterator nodes_iterator;
831 static nodes_iterator nodes_begin(SelectionDAG *G) {
832 return G->allnodes_begin();
834 static nodes_iterator nodes_end(SelectionDAG *G) {
835 return G->allnodes_end();
839 } // end namespace llvm