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;
35 class MachineFunction;
36 class MachineConstantPoolValue;
37 class FunctionLoweringInfo;
39 template<> struct ilist_traits<SDNode> : public ilist_default_traits<SDNode> {
41 mutable SDNode Sentinel;
43 ilist_traits() : Sentinel(ISD::DELETED_NODE, SDVTList()) {}
45 SDNode *createSentinel() const {
48 static void destroySentinel(SDNode *) {}
50 static void deleteNode(SDNode *) {
51 assert(0 && "ilist_traits<SDNode> shouldn't see a deleteNode call!");
54 static void createNode(const SDNode &);
58 Unrestricted, // Combine may create illegal operations and illegal types.
59 NoIllegalTypes, // Combine may create illegal operations but no illegal types.
60 NoIllegalOperations // Combine may only create legal operations and types.
63 /// SelectionDAG class - This is used to represent a portion of an LLVM function
64 /// in a low-level Data Dependence DAG representation suitable for instruction
65 /// selection. This DAG is constructed as the first step of instruction
66 /// selection in order to allow implementation of machine specific optimizations
67 /// and code simplifications.
69 /// The representation used by the SelectionDAG is a target-independent
70 /// representation, which has some similarities to the GCC RTL representation,
71 /// but is significantly more simple, powerful, and is a graph form instead of a
77 FunctionLoweringInfo &FLI;
78 MachineModuleInfo *MMI;
80 /// EntryNode - The starting token.
83 /// Root - The root of the entire DAG.
86 /// AllNodes - A linked list of nodes in the current DAG.
87 ilist<SDNode> AllNodes;
89 /// NodeAllocatorType - The AllocatorType for allocating SDNodes. We use
90 /// pool allocation with recycling.
91 typedef RecyclingAllocator<BumpPtrAllocator, SDNode, sizeof(LargestSDNode),
92 AlignOf<MostAlignedSDNode>::Alignment>
95 /// NodeAllocator - Pool allocation for nodes.
96 NodeAllocatorType NodeAllocator;
98 /// CSEMap - This structure is used to memoize nodes, automatically performing
99 /// CSE with existing nodes with a duplicate is requested.
100 FoldingSet<SDNode> CSEMap;
102 /// OperandAllocator - Pool allocation for machine-opcode SDNode operands.
103 BumpPtrAllocator OperandAllocator;
105 /// Allocator - Pool allocation for misc. objects that are created once per
107 BumpPtrAllocator Allocator;
109 /// VerifyNode - Sanity check the given node. Aborts if it is invalid.
110 void VerifyNode(SDNode *N);
112 /// setGraphColorHelper - Implementation of setSubgraphColor.
113 /// Return whether we had to truncate the search.
115 bool setSubgraphColorHelper(SDNode *N, const char *Color, DenseSet<SDNode *> &visited,
116 int level, bool &printed);
119 SelectionDAG(TargetLowering &tli, FunctionLoweringInfo &fli);
122 /// init - Prepare this SelectionDAG to process code in the given
125 void init(MachineFunction &mf, MachineModuleInfo *mmi);
127 /// clear - Clear state and free memory necessary to make this
128 /// SelectionDAG ready to process a new block.
132 MachineFunction &getMachineFunction() const { return *MF; }
133 const TargetMachine &getTarget() const;
134 TargetLowering &getTargetLoweringInfo() const { return TLI; }
135 FunctionLoweringInfo &getFunctionLoweringInfo() const { return FLI; }
136 MachineModuleInfo *getMachineModuleInfo() const { return MMI; }
138 /// viewGraph - Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
140 void viewGraph(const std::string &Title);
144 std::map<const SDNode *, std::string> NodeGraphAttrs;
147 /// clearGraphAttrs - Clear all previously defined node graph attributes.
148 /// Intended to be used from a debugging tool (eg. gdb).
149 void clearGraphAttrs();
151 /// setGraphAttrs - Set graph attributes for a node. (eg. "color=red".)
153 void setGraphAttrs(const SDNode *N, const char *Attrs);
155 /// getGraphAttrs - Get graph attributes for a node. (eg. "color=red".)
156 /// Used from getNodeAttributes.
157 const std::string getGraphAttrs(const SDNode *N) const;
159 /// setGraphColor - Convenience for setting node color attribute.
161 void setGraphColor(const SDNode *N, const char *Color);
163 /// setGraphColor - Convenience for setting subgraph color attribute.
165 void setSubgraphColor(SDNode *N, const char *Color);
167 typedef ilist<SDNode>::const_iterator allnodes_const_iterator;
168 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
169 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
170 typedef ilist<SDNode>::iterator allnodes_iterator;
171 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
172 allnodes_iterator allnodes_end() { return AllNodes.end(); }
173 ilist<SDNode>::size_type allnodes_size() const {
174 return AllNodes.size();
177 /// getRoot - Return the root tag of the SelectionDAG.
179 const SDValue &getRoot() const { return Root; }
181 /// getEntryNode - Return the token chain corresponding to the entry of the
183 SDValue getEntryNode() const {
184 return SDValue(const_cast<SDNode *>(&EntryNode), 0);
187 /// setRoot - Set the current root tag of the SelectionDAG.
189 const SDValue &setRoot(SDValue N) {
190 assert((!N.getNode() || N.getValueType() == MVT::Other) &&
191 "DAG root value is not a chain!");
195 /// Combine - This iterates over the nodes in the SelectionDAG, folding
196 /// certain types of nodes together, or eliminating superfluous nodes. The
197 /// Level argument controls whether Combine is allowed to produce nodes and
198 /// types that are illegal on the target.
199 void Combine(CombineLevel Level, AliasAnalysis &AA, bool Fast);
201 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that
202 /// only uses types natively supported by the target. Returns "true" if it
203 /// made any changes.
205 /// Note that this is an involved process that may invalidate pointers into
207 bool LegalizeTypes();
209 /// Legalize - This transforms the SelectionDAG into a SelectionDAG that is
210 /// compatible with the target instruction selector, as indicated by the
211 /// TargetLowering object.
213 /// Note that this is an involved process that may invalidate pointers into
217 /// RemoveDeadNodes - This method deletes all unreachable nodes in the
219 void RemoveDeadNodes();
221 /// DeleteNode - Remove the specified node from the system. This node must
222 /// have no referrers.
223 void DeleteNode(SDNode *N);
225 /// getVTList - Return an SDVTList that represents the list of values
227 SDVTList getVTList(MVT VT);
228 SDVTList getVTList(MVT VT1, MVT VT2);
229 SDVTList getVTList(MVT VT1, MVT VT2, MVT VT3);
230 SDVTList getVTList(const MVT *VTs, unsigned NumVTs);
232 /// getNodeValueTypes - These are obsolete, use getVTList instead.
233 const MVT *getNodeValueTypes(MVT VT) {
234 return getVTList(VT).VTs;
236 const MVT *getNodeValueTypes(MVT VT1, MVT VT2) {
237 return getVTList(VT1, VT2).VTs;
239 const MVT *getNodeValueTypes(MVT VT1, MVT VT2, MVT VT3) {
240 return getVTList(VT1, VT2, VT3).VTs;
242 const MVT *getNodeValueTypes(const std::vector<MVT> &vtList) {
243 return getVTList(&vtList[0], (unsigned)vtList.size()).VTs;
247 //===--------------------------------------------------------------------===//
248 // Node creation methods.
250 SDValue getConstant(uint64_t Val, MVT VT, bool isTarget = false);
251 SDValue getConstant(const APInt &Val, MVT VT, bool isTarget = false);
252 SDValue getConstant(const ConstantInt &Val, MVT VT, bool isTarget = false);
253 SDValue getIntPtrConstant(uint64_t Val, bool isTarget = false);
254 SDValue getTargetConstant(uint64_t Val, MVT VT) {
255 return getConstant(Val, VT, true);
257 SDValue getTargetConstant(const APInt &Val, MVT VT) {
258 return getConstant(Val, VT, true);
260 SDValue getTargetConstant(const ConstantInt &Val, MVT VT) {
261 return getConstant(Val, VT, true);
263 SDValue getConstantFP(double Val, MVT VT, bool isTarget = false);
264 SDValue getConstantFP(const APFloat& Val, MVT VT, bool isTarget = false);
265 SDValue getConstantFP(const ConstantFP &CF, MVT VT, bool isTarget = false);
266 SDValue getTargetConstantFP(double Val, MVT VT) {
267 return getConstantFP(Val, VT, true);
269 SDValue getTargetConstantFP(const APFloat& Val, MVT VT) {
270 return getConstantFP(Val, VT, true);
272 SDValue getTargetConstantFP(const ConstantFP &Val, MVT VT) {
273 return getConstantFP(Val, VT, true);
275 SDValue getGlobalAddress(const GlobalValue *GV, MVT VT,
276 int64_t offset = 0, bool isTargetGA = false);
277 SDValue getTargetGlobalAddress(const GlobalValue *GV, MVT VT,
278 int64_t offset = 0) {
279 return getGlobalAddress(GV, VT, offset, true);
281 SDValue getFrameIndex(int FI, MVT VT, bool isTarget = false);
282 SDValue getTargetFrameIndex(int FI, MVT VT) {
283 return getFrameIndex(FI, VT, true);
285 SDValue getJumpTable(int JTI, MVT VT, bool isTarget = false);
286 SDValue getTargetJumpTable(int JTI, MVT VT) {
287 return getJumpTable(JTI, VT, true);
289 SDValue getConstantPool(Constant *C, MVT VT,
290 unsigned Align = 0, int Offs = 0, bool isT=false);
291 SDValue getTargetConstantPool(Constant *C, MVT VT,
292 unsigned Align = 0, int Offset = 0) {
293 return getConstantPool(C, VT, Align, Offset, true);
295 SDValue getConstantPool(MachineConstantPoolValue *C, MVT VT,
296 unsigned Align = 0, int Offs = 0, bool isT=false);
297 SDValue getTargetConstantPool(MachineConstantPoolValue *C,
298 MVT VT, unsigned Align = 0,
300 return getConstantPool(C, VT, Align, Offset, true);
302 SDValue getBasicBlock(MachineBasicBlock *MBB);
303 SDValue getExternalSymbol(const char *Sym, MVT VT);
304 SDValue getTargetExternalSymbol(const char *Sym, MVT VT);
305 SDValue getArgFlags(ISD::ArgFlagsTy Flags);
306 SDValue getValueType(MVT);
307 SDValue getRegister(unsigned Reg, MVT VT);
308 SDValue getDbgStopPoint(SDValue Root, unsigned Line, unsigned Col,
309 const CompileUnitDesc *CU);
310 SDValue getLabel(unsigned Opcode, SDValue Root, unsigned LabelID);
312 SDValue getCopyToReg(SDValue Chain, unsigned Reg, SDValue N) {
313 return getNode(ISD::CopyToReg, MVT::Other, Chain,
314 getRegister(Reg, N.getValueType()), N);
317 // This version of the getCopyToReg method takes an extra operand, which
318 // indicates that there is potentially an incoming flag value (if Flag is not
319 // null) and that there should be a flag result.
320 SDValue getCopyToReg(SDValue Chain, unsigned Reg, SDValue N,
322 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
323 SDValue Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Flag };
324 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.getNode() ? 4 : 3);
327 // Similar to last getCopyToReg() except parameter Reg is a SDValue
328 SDValue getCopyToReg(SDValue Chain, SDValue Reg, SDValue N,
330 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
331 SDValue Ops[] = { Chain, Reg, N, Flag };
332 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.getNode() ? 4 : 3);
335 SDValue getCopyFromReg(SDValue Chain, unsigned Reg, MVT VT) {
336 const MVT *VTs = getNodeValueTypes(VT, MVT::Other);
337 SDValue Ops[] = { Chain, getRegister(Reg, VT) };
338 return getNode(ISD::CopyFromReg, VTs, 2, Ops, 2);
341 // This version of the getCopyFromReg method takes an extra operand, which
342 // indicates that there is potentially an incoming flag value (if Flag is not
343 // null) and that there should be a flag result.
344 SDValue getCopyFromReg(SDValue Chain, unsigned Reg, MVT VT,
346 const MVT *VTs = getNodeValueTypes(VT, MVT::Other, MVT::Flag);
347 SDValue Ops[] = { Chain, getRegister(Reg, VT), Flag };
348 return getNode(ISD::CopyFromReg, VTs, 3, Ops, Flag.getNode() ? 3 : 2);
351 SDValue getCondCode(ISD::CondCode Cond);
353 /// Returns the ConvertRndSat Note: Avoid using this node because it may
354 /// disappear in the future and most targets don't support it.
355 SDValue getConvertRndSat(MVT VT, SDValue Val, SDValue DTy, SDValue STy,
356 SDValue Rnd, SDValue Sat, ISD::CvtCode Code);
358 /// getZeroExtendInReg - Return the expression required to zero extend the Op
359 /// value assuming it was the smaller SrcTy value.
360 SDValue getZeroExtendInReg(SDValue Op, MVT SrcTy);
362 /// getCALLSEQ_START - Return a new CALLSEQ_START node, which always must have
363 /// a flag result (to ensure it's not CSE'd).
364 SDValue getCALLSEQ_START(SDValue Chain, SDValue Op) {
365 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
366 SDValue Ops[] = { Chain, Op };
367 return getNode(ISD::CALLSEQ_START, VTs, 2, Ops, 2);
370 /// getCALLSEQ_END - Return a new CALLSEQ_END node, which always must have a
371 /// flag result (to ensure it's not CSE'd).
372 SDValue getCALLSEQ_END(SDValue Chain, SDValue Op1, SDValue Op2,
374 SDVTList NodeTys = getVTList(MVT::Other, MVT::Flag);
375 SmallVector<SDValue, 4> Ops;
376 Ops.push_back(Chain);
379 Ops.push_back(InFlag);
380 return getNode(ISD::CALLSEQ_END, NodeTys, &Ops[0],
381 (unsigned)Ops.size() - (InFlag.getNode() == 0 ? 1 : 0));
384 /// getNode - Gets or creates the specified node.
386 SDValue getNode(unsigned Opcode, MVT VT);
387 SDValue getNode(unsigned Opcode, MVT VT, SDValue N);
388 SDValue getNode(unsigned Opcode, MVT VT, SDValue N1, SDValue N2);
389 SDValue getNode(unsigned Opcode, MVT VT,
390 SDValue N1, SDValue N2, SDValue N3);
391 SDValue getNode(unsigned Opcode, MVT VT,
392 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
393 SDValue getNode(unsigned Opcode, MVT VT,
394 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
396 SDValue getNode(unsigned Opcode, MVT VT,
397 const SDValue *Ops, unsigned NumOps);
398 SDValue getNode(unsigned Opcode, MVT VT,
399 const SDUse *Ops, unsigned NumOps);
400 SDValue getNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
401 const SDValue *Ops, unsigned NumOps);
402 SDValue getNode(unsigned Opcode, const MVT *VTs, unsigned NumVTs,
403 const SDValue *Ops, unsigned NumOps);
404 SDValue getNode(unsigned Opcode, SDVTList VTs);
405 SDValue getNode(unsigned Opcode, SDVTList VTs, SDValue N);
406 SDValue getNode(unsigned Opcode, SDVTList VTs, SDValue N1, SDValue N2);
407 SDValue getNode(unsigned Opcode, SDVTList VTs,
408 SDValue N1, SDValue N2, SDValue N3);
409 SDValue getNode(unsigned Opcode, SDVTList VTs,
410 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
411 SDValue getNode(unsigned Opcode, SDVTList VTs,
412 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
414 SDValue getNode(unsigned Opcode, SDVTList VTs,
415 const SDValue *Ops, unsigned NumOps);
417 SDValue getMemcpy(SDValue Chain, SDValue Dst, SDValue Src,
418 SDValue Size, unsigned Align, bool AlwaysInline,
419 const Value *DstSV, uint64_t DstSVOff,
420 const Value *SrcSV, uint64_t SrcSVOff);
422 SDValue getMemmove(SDValue Chain, SDValue Dst, SDValue Src,
423 SDValue Size, unsigned Align,
424 const Value *DstSV, uint64_t DstOSVff,
425 const Value *SrcSV, uint64_t SrcSVOff);
427 SDValue getMemset(SDValue Chain, SDValue Dst, SDValue Src,
428 SDValue Size, unsigned Align,
429 const Value *DstSV, uint64_t DstSVOff);
431 /// getSetCC - Helper function to make it easier to build SetCC's if you just
432 /// have an ISD::CondCode instead of an SDValue.
434 SDValue getSetCC(MVT VT, SDValue LHS, SDValue RHS,
435 ISD::CondCode Cond) {
436 return getNode(ISD::SETCC, VT, LHS, RHS, getCondCode(Cond));
439 /// getVSetCC - Helper function to make it easier to build VSetCC's nodes
440 /// if you just have an ISD::CondCode instead of an SDValue.
442 SDValue getVSetCC(MVT VT, SDValue LHS, SDValue RHS,
443 ISD::CondCode Cond) {
444 return getNode(ISD::VSETCC, VT, LHS, RHS, getCondCode(Cond));
447 /// getSelectCC - Helper function to make it easier to build SelectCC's if you
448 /// just have an ISD::CondCode instead of an SDValue.
450 SDValue getSelectCC(SDValue LHS, SDValue RHS,
451 SDValue True, SDValue False, ISD::CondCode Cond) {
452 return getNode(ISD::SELECT_CC, True.getValueType(), LHS, RHS, True, False,
456 /// getVAArg - VAArg produces a result and token chain, and takes a pointer
457 /// and a source value as input.
458 SDValue getVAArg(MVT VT, SDValue Chain, SDValue Ptr,
461 /// getAtomic - Gets a node for an atomic op, produces result and chain and
463 SDValue getAtomic(unsigned Opcode, SDValue Chain, SDValue Ptr,
464 SDValue Cmp, SDValue Swp, const Value* PtrVal,
465 unsigned Alignment=0);
467 /// getAtomic - Gets a node for an atomic op, produces result and chain and
468 /// takes 2 operands.
469 SDValue getAtomic(unsigned Opcode, SDValue Chain, SDValue Ptr,
470 SDValue Val, const Value* PtrVal,
471 unsigned Alignment = 0);
473 /// getMemIntrinsicNode - Creates a MemIntrinsicNode that may produce a
474 /// result and takes a list of operands.
475 SDValue getMemIntrinsicNode(unsigned Opcode,
476 const MVT *VTs, unsigned NumVTs,
477 const SDValue *Ops, unsigned NumOps,
478 MVT MemVT, const Value *srcValue, int SVOff,
479 unsigned Align = 0, bool Vol = false,
480 bool ReadMem = true, bool WriteMem = true);
482 SDValue getMemIntrinsicNode(unsigned Opcode, SDVTList VTList,
483 const SDValue *Ops, unsigned NumOps,
484 MVT MemVT, const Value *srcValue, int SVOff,
485 unsigned Align = 0, bool Vol = false,
486 bool ReadMem = true, bool WriteMem = true);
488 /// getMergeValues - Create a MERGE_VALUES node from the given operands.
489 SDValue getMergeValues(const SDValue *Ops, unsigned NumOps);
491 /// getCall - Create a CALL node from the given information.
493 SDValue getCall(unsigned CallingConv, bool IsVarArgs, bool IsTailCall,
494 bool isInreg, SDVTList VTs, const SDValue *Operands,
495 unsigned NumOperands);
497 /// getLoad - Loads are not normal binary operators: their result type is not
498 /// determined by their operands, and they produce a value AND a token chain.
500 SDValue getLoad(MVT VT, SDValue Chain, SDValue Ptr,
501 const Value *SV, int SVOffset, bool isVolatile=false,
502 unsigned Alignment=0);
503 SDValue getExtLoad(ISD::LoadExtType ExtType, MVT VT,
504 SDValue Chain, SDValue Ptr, const Value *SV,
505 int SVOffset, MVT EVT, bool isVolatile=false,
506 unsigned Alignment=0);
507 SDValue getIndexedLoad(SDValue OrigLoad, SDValue Base,
508 SDValue Offset, ISD::MemIndexedMode AM);
509 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
510 MVT VT, SDValue Chain,
511 SDValue Ptr, SDValue Offset,
512 const Value *SV, int SVOffset, MVT EVT,
513 bool isVolatile=false, unsigned Alignment=0);
515 /// getStore - Helper function to build ISD::STORE nodes.
517 SDValue getStore(SDValue Chain, SDValue Val, SDValue Ptr,
518 const Value *SV, int SVOffset, bool isVolatile=false,
519 unsigned Alignment=0);
520 SDValue getTruncStore(SDValue Chain, SDValue Val, SDValue Ptr,
521 const Value *SV, int SVOffset, MVT TVT,
522 bool isVolatile=false, unsigned Alignment=0);
523 SDValue getIndexedStore(SDValue OrigStoe, SDValue Base,
524 SDValue Offset, ISD::MemIndexedMode AM);
526 // getSrcValue - Construct a node to track a Value* through the backend.
527 SDValue getSrcValue(const Value *v);
529 // getMemOperand - Construct a node to track a memory reference
530 // through the backend.
531 SDValue getMemOperand(const MachineMemOperand &MO);
533 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the
534 /// specified operands. If the resultant node already exists in the DAG,
535 /// this does not modify the specified node, instead it returns the node that
536 /// already exists. If the resultant node does not exist in the DAG, the
537 /// input node is returned. As a degenerate case, if you specify the same
538 /// input operands as the node already has, the input node is returned.
539 SDValue UpdateNodeOperands(SDValue N, SDValue Op);
540 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2);
541 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
543 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
544 SDValue Op3, SDValue Op4);
545 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
546 SDValue Op3, SDValue Op4, SDValue Op5);
547 SDValue UpdateNodeOperands(SDValue N,
548 const SDValue *Ops, unsigned NumOps);
550 /// SelectNodeTo - These are used for target selectors to *mutate* the
551 /// specified node to have the specified return type, Target opcode, and
552 /// operands. Note that target opcodes are stored as
553 /// ~TargetOpcode in the node opcode field. The resultant node is returned.
554 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT);
555 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, SDValue Op1);
556 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
557 SDValue Op1, SDValue Op2);
558 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
559 SDValue Op1, SDValue Op2, SDValue Op3);
560 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
561 const SDValue *Ops, unsigned NumOps);
562 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, MVT VT2);
563 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
564 MVT VT2, const SDValue *Ops, unsigned NumOps);
565 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
566 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps);
567 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
568 MVT VT2, SDValue Op1);
569 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
570 MVT VT2, SDValue Op1, SDValue Op2);
571 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
572 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
573 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
574 const SDValue *Ops, unsigned NumOps);
576 /// MorphNodeTo - These *mutate* the specified node to have the specified
577 /// return type, opcode, and operands.
578 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT);
579 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT, SDValue Op1);
580 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
581 SDValue Op1, SDValue Op2);
582 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
583 SDValue Op1, SDValue Op2, SDValue Op3);
584 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
585 const SDValue *Ops, unsigned NumOps);
586 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1, MVT VT2);
587 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
588 MVT VT2, const SDValue *Ops, unsigned NumOps);
589 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
590 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps);
591 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
592 MVT VT2, SDValue Op1);
593 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
594 MVT VT2, SDValue Op1, SDValue Op2);
595 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
596 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
597 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
598 const SDValue *Ops, unsigned NumOps);
600 /// getTargetNode - These are used for target selectors to create a new node
601 /// with specified return type(s), target opcode, and operands.
603 /// Note that getTargetNode returns the resultant node. If there is already a
604 /// node of the specified opcode and operands, it returns that node instead of
606 SDNode *getTargetNode(unsigned Opcode, MVT VT);
607 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1);
608 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1, SDValue Op2);
609 SDNode *getTargetNode(unsigned Opcode, MVT VT,
610 SDValue Op1, SDValue Op2, SDValue Op3);
611 SDNode *getTargetNode(unsigned Opcode, MVT VT,
612 const SDValue *Ops, unsigned NumOps);
613 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2);
614 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, SDValue Op1);
615 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
616 MVT VT2, SDValue Op1, SDValue Op2);
617 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
618 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
619 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2,
620 const SDValue *Ops, unsigned NumOps);
621 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
622 SDValue Op1, SDValue Op2);
623 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
624 SDValue Op1, SDValue Op2, SDValue Op3);
625 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
626 const SDValue *Ops, unsigned NumOps);
627 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, MVT VT4,
628 const SDValue *Ops, unsigned NumOps);
629 SDNode *getTargetNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
630 const SDValue *Ops, unsigned NumOps);
632 /// getNodeIfExists - Get the specified node if it's already available, or
633 /// else return NULL.
634 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs,
635 const SDValue *Ops, unsigned NumOps);
637 /// DAGUpdateListener - Clients of various APIs that cause global effects on
638 /// the DAG can optionally implement this interface. This allows the clients
639 /// to handle the various sorts of updates that happen.
640 class DAGUpdateListener {
642 virtual ~DAGUpdateListener();
644 /// NodeDeleted - The node N that was deleted and, if E is not null, an
645 /// equivalent node E that replaced it.
646 virtual void NodeDeleted(SDNode *N, SDNode *E) = 0;
648 /// NodeUpdated - The node N that was updated.
649 virtual void NodeUpdated(SDNode *N) = 0;
652 /// RemoveDeadNode - Remove the specified node from the system. If any of its
653 /// operands then becomes dead, remove them as well. Inform UpdateListener
654 /// for each node deleted.
655 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0);
657 /// RemoveDeadNodes - This method deletes the unreachable nodes in the
658 /// given list, and any nodes that become unreachable as a result.
659 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes,
660 DAGUpdateListener *UpdateListener = 0);
662 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
663 /// This can cause recursive merging of nodes in the DAG. Use the first
664 /// version if 'From' is known to have a single result, use the second
665 /// if you have two nodes with identical results, use the third otherwise.
667 /// These methods all take an optional UpdateListener, which (if not null) is
668 /// informed about nodes that are deleted and modified due to recursive
669 /// changes in the dag.
671 void ReplaceAllUsesWith(SDValue From, SDValue Op,
672 DAGUpdateListener *UpdateListener = 0);
673 void ReplaceAllUsesWith(SDNode *From, SDNode *To,
674 DAGUpdateListener *UpdateListener = 0);
675 void ReplaceAllUsesWith(SDNode *From, const SDValue *To,
676 DAGUpdateListener *UpdateListener = 0);
678 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving
679 /// uses of other values produced by From.Val alone.
680 void ReplaceAllUsesOfValueWith(SDValue From, SDValue To,
681 DAGUpdateListener *UpdateListener = 0);
683 /// ReplaceAllUsesOfValuesWith - Like ReplaceAllUsesOfValueWith, but
684 /// for multiple values at once. This correctly handles the case where
685 /// there is an overlap between the From values and the To values.
686 void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To,
688 DAGUpdateListener *UpdateListener = 0);
690 /// AssignTopologicalOrder - Topological-sort the AllNodes list and a
691 /// assign a unique node id for each node in the DAG based on their
692 /// topological order. Returns the number of nodes.
693 unsigned AssignTopologicalOrder();
695 /// RepositionNode - Move node N in the AllNodes list to be immediately
696 /// before the given iterator Position. This may be used to update the
697 /// topological ordering when the list of nodes is modified.
698 void RepositionNode(allnodes_iterator Position, SDNode *N) {
699 AllNodes.insert(Position, AllNodes.remove(N));
702 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary
704 static bool isCommutativeBinOp(unsigned Opcode) {
705 // FIXME: This should get its info from the td file, so that we can include
720 case ISD::ADDE: return true;
721 default: return false;
727 /// CreateStackTemporary - Create a stack temporary, suitable for holding the
728 /// specified value type. If minAlign is specified, the slot size will have
729 /// at least that alignment.
730 SDValue CreateStackTemporary(MVT VT, unsigned minAlign = 1);
732 /// FoldConstantArithmetic -
733 SDValue FoldConstantArithmetic(unsigned Opcode,
735 ConstantSDNode *Cst1,
736 ConstantSDNode *Cst2);
738 /// FoldSetCC - Constant fold a setcc to true or false.
739 SDValue FoldSetCC(MVT VT, SDValue N1,
740 SDValue N2, ISD::CondCode Cond);
742 /// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We
743 /// use this predicate to simplify operations downstream.
744 bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const;
746 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We
747 /// use this predicate to simplify operations downstream. Op and Mask are
748 /// known to be the same type.
749 bool MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth = 0)
752 /// ComputeMaskedBits - Determine which of the bits specified in Mask are
753 /// known to be either zero or one and return them in the KnownZero/KnownOne
754 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit
755 /// processing. Targets can implement the computeMaskedBitsForTargetNode
756 /// method in the TargetLowering class to allow target nodes to be understood.
757 void ComputeMaskedBits(SDValue Op, const APInt &Mask, APInt &KnownZero,
758 APInt &KnownOne, unsigned Depth = 0) const;
760 /// ComputeNumSignBits - Return the number of times the sign bit of the
761 /// register is replicated into the other bits. We know that at least 1 bit
762 /// is always equal to the sign bit (itself), but other cases can give us
763 /// information. For example, immediately after an "SRA X, 2", we know that
764 /// the top 3 bits are all equal to each other, so we return 3. Targets can
765 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
766 /// class to allow target nodes to be understood.
767 unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const;
769 /// isVerifiedDebugInfoDesc - Returns true if the specified SDValue has
770 /// been verified as a debug information descriptor.
771 bool isVerifiedDebugInfoDesc(SDValue Op) const;
773 /// getShuffleScalarElt - Returns the scalar element that will make up the ith
774 /// element of the result of the vector shuffle.
775 SDValue getShuffleScalarElt(const SDNode *N, unsigned Idx);
778 bool RemoveNodeFromCSEMaps(SDNode *N);
779 SDNode *AddNonLeafNodeToCSEMaps(SDNode *N);
780 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos);
781 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2,
783 SDNode *FindModifiedNodeSlot(SDNode *N, const SDValue *Ops, unsigned NumOps,
786 void DeleteNodeNotInCSEMaps(SDNode *N);
788 unsigned getMVTAlignment(MVT MemoryVT) const;
790 void allnodes_clear();
792 // List of non-single value types.
793 std::vector<SDVTList> VTList;
795 // Maps to auto-CSE operations.
796 std::vector<CondCodeSDNode*> CondCodeNodes;
798 std::vector<SDNode*> ValueTypeNodes;
799 std::map<MVT, SDNode*, MVT::compareRawBits> ExtendedValueTypeNodes;
800 StringMap<SDNode*> ExternalSymbols;
801 StringMap<SDNode*> TargetExternalSymbols;
804 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
805 typedef SelectionDAG::allnodes_iterator nodes_iterator;
806 static nodes_iterator nodes_begin(SelectionDAG *G) {
807 return G->allnodes_begin();
809 static nodes_iterator nodes_end(SelectionDAG *G) {
810 return G->allnodes_end();
814 } // end namespace llvm