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 /// Allowed to return something different (and simpler) if Simplify is true.
490 SDValue getMergeValues(const SDValue *Ops, unsigned NumOps,
491 bool Simplify = true);
493 /// getMergeValues - Create a MERGE_VALUES node from the given types and ops.
494 /// Allowed to return something different (and simpler) if Simplify is true.
495 /// May be faster than the above version if VTs is known and NumOps is large.
496 SDValue getMergeValues(SDVTList VTs, const SDValue *Ops, unsigned NumOps,
497 bool Simplify = true) {
498 if (Simplify && NumOps == 1)
500 return getNode(ISD::MERGE_VALUES, VTs, Ops, NumOps);
503 /// getCall - Create a CALL node from the given information.
505 SDValue getCall(unsigned CallingConv, bool IsVarArgs, bool IsTailCall,
506 bool isInreg, SDVTList VTs, const SDValue *Operands,
507 unsigned NumOperands);
509 /// getLoad - Loads are not normal binary operators: their result type is not
510 /// determined by their operands, and they produce a value AND a token chain.
512 SDValue getLoad(MVT VT, SDValue Chain, SDValue Ptr,
513 const Value *SV, int SVOffset, bool isVolatile=false,
514 unsigned Alignment=0);
515 SDValue getExtLoad(ISD::LoadExtType ExtType, MVT VT,
516 SDValue Chain, SDValue Ptr, const Value *SV,
517 int SVOffset, MVT EVT, bool isVolatile=false,
518 unsigned Alignment=0);
519 SDValue getIndexedLoad(SDValue OrigLoad, SDValue Base,
520 SDValue Offset, ISD::MemIndexedMode AM);
521 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
522 MVT VT, SDValue Chain,
523 SDValue Ptr, SDValue Offset,
524 const Value *SV, int SVOffset, MVT EVT,
525 bool isVolatile=false, unsigned Alignment=0);
527 /// getStore - Helper function to build ISD::STORE nodes.
529 SDValue getStore(SDValue Chain, SDValue Val, SDValue Ptr,
530 const Value *SV, int SVOffset, bool isVolatile=false,
531 unsigned Alignment=0);
532 SDValue getTruncStore(SDValue Chain, SDValue Val, SDValue Ptr,
533 const Value *SV, int SVOffset, MVT TVT,
534 bool isVolatile=false, unsigned Alignment=0);
535 SDValue getIndexedStore(SDValue OrigStoe, SDValue Base,
536 SDValue Offset, ISD::MemIndexedMode AM);
538 // getSrcValue - Construct a node to track a Value* through the backend.
539 SDValue getSrcValue(const Value *v);
541 // getMemOperand - Construct a node to track a memory reference
542 // through the backend.
543 SDValue getMemOperand(const MachineMemOperand &MO);
545 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the
546 /// specified operands. If the resultant node already exists in the DAG,
547 /// this does not modify the specified node, instead it returns the node that
548 /// already exists. If the resultant node does not exist in the DAG, the
549 /// input node is returned. As a degenerate case, if you specify the same
550 /// input operands as the node already has, the input node is returned.
551 SDValue UpdateNodeOperands(SDValue N, SDValue Op);
552 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2);
553 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
555 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
556 SDValue Op3, SDValue Op4);
557 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
558 SDValue Op3, SDValue Op4, SDValue Op5);
559 SDValue UpdateNodeOperands(SDValue N,
560 const SDValue *Ops, unsigned NumOps);
562 /// SelectNodeTo - These are used for target selectors to *mutate* the
563 /// specified node to have the specified return type, Target opcode, and
564 /// operands. Note that target opcodes are stored as
565 /// ~TargetOpcode in the node opcode field. The resultant node is returned.
566 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT);
567 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, SDValue Op1);
568 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
569 SDValue Op1, SDValue Op2);
570 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
571 SDValue Op1, SDValue Op2, SDValue Op3);
572 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
573 const SDValue *Ops, unsigned NumOps);
574 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, MVT VT2);
575 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
576 MVT VT2, const SDValue *Ops, unsigned NumOps);
577 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
578 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps);
579 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
580 MVT VT2, SDValue Op1);
581 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
582 MVT VT2, SDValue Op1, SDValue Op2);
583 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
584 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
585 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
586 const SDValue *Ops, unsigned NumOps);
588 /// MorphNodeTo - These *mutate* the specified node to have the specified
589 /// return type, opcode, and operands.
590 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT);
591 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT, SDValue Op1);
592 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
593 SDValue Op1, SDValue Op2);
594 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
595 SDValue Op1, SDValue Op2, SDValue Op3);
596 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
597 const SDValue *Ops, unsigned NumOps);
598 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1, MVT VT2);
599 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
600 MVT VT2, const SDValue *Ops, unsigned NumOps);
601 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
602 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps);
603 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
604 MVT VT2, SDValue Op1);
605 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
606 MVT VT2, SDValue Op1, SDValue Op2);
607 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
608 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
609 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
610 const SDValue *Ops, unsigned NumOps);
612 /// getTargetNode - These are used for target selectors to create a new node
613 /// with specified return type(s), target opcode, and operands.
615 /// Note that getTargetNode returns the resultant node. If there is already a
616 /// node of the specified opcode and operands, it returns that node instead of
618 SDNode *getTargetNode(unsigned Opcode, MVT VT);
619 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1);
620 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1, SDValue Op2);
621 SDNode *getTargetNode(unsigned Opcode, MVT VT,
622 SDValue Op1, SDValue Op2, SDValue Op3);
623 SDNode *getTargetNode(unsigned Opcode, MVT VT,
624 const SDValue *Ops, unsigned NumOps);
625 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2);
626 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, SDValue Op1);
627 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
628 MVT VT2, SDValue Op1, SDValue Op2);
629 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
630 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
631 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2,
632 const SDValue *Ops, unsigned NumOps);
633 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
634 SDValue Op1, SDValue Op2);
635 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
636 SDValue Op1, SDValue Op2, SDValue Op3);
637 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
638 const SDValue *Ops, unsigned NumOps);
639 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, MVT VT4,
640 const SDValue *Ops, unsigned NumOps);
641 SDNode *getTargetNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
642 const SDValue *Ops, unsigned NumOps);
644 /// getNodeIfExists - Get the specified node if it's already available, or
645 /// else return NULL.
646 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs,
647 const SDValue *Ops, unsigned NumOps);
649 /// DAGUpdateListener - Clients of various APIs that cause global effects on
650 /// the DAG can optionally implement this interface. This allows the clients
651 /// to handle the various sorts of updates that happen.
652 class DAGUpdateListener {
654 virtual ~DAGUpdateListener();
656 /// NodeDeleted - The node N that was deleted and, if E is not null, an
657 /// equivalent node E that replaced it.
658 virtual void NodeDeleted(SDNode *N, SDNode *E) = 0;
660 /// NodeUpdated - The node N that was updated.
661 virtual void NodeUpdated(SDNode *N) = 0;
664 /// RemoveDeadNode - Remove the specified node from the system. If any of its
665 /// operands then becomes dead, remove them as well. Inform UpdateListener
666 /// for each node deleted.
667 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0);
669 /// RemoveDeadNodes - This method deletes the unreachable nodes in the
670 /// given list, and any nodes that become unreachable as a result.
671 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes,
672 DAGUpdateListener *UpdateListener = 0);
674 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
675 /// This can cause recursive merging of nodes in the DAG. Use the first
676 /// version if 'From' is known to have a single result, use the second
677 /// if you have two nodes with identical results, use the third otherwise.
679 /// These methods all take an optional UpdateListener, which (if not null) is
680 /// informed about nodes that are deleted and modified due to recursive
681 /// changes in the dag.
683 void ReplaceAllUsesWith(SDValue From, SDValue Op,
684 DAGUpdateListener *UpdateListener = 0);
685 void ReplaceAllUsesWith(SDNode *From, SDNode *To,
686 DAGUpdateListener *UpdateListener = 0);
687 void ReplaceAllUsesWith(SDNode *From, const SDValue *To,
688 DAGUpdateListener *UpdateListener = 0);
690 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving
691 /// uses of other values produced by From.Val alone.
692 void ReplaceAllUsesOfValueWith(SDValue From, SDValue To,
693 DAGUpdateListener *UpdateListener = 0);
695 /// ReplaceAllUsesOfValuesWith - Like ReplaceAllUsesOfValueWith, but
696 /// for multiple values at once. This correctly handles the case where
697 /// there is an overlap between the From values and the To values.
698 void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To,
700 DAGUpdateListener *UpdateListener = 0);
702 /// AssignTopologicalOrder - Topological-sort the AllNodes list and a
703 /// assign a unique node id for each node in the DAG based on their
704 /// topological order. Returns the number of nodes.
705 unsigned AssignTopologicalOrder();
707 /// RepositionNode - Move node N in the AllNodes list to be immediately
708 /// before the given iterator Position. This may be used to update the
709 /// topological ordering when the list of nodes is modified.
710 void RepositionNode(allnodes_iterator Position, SDNode *N) {
711 AllNodes.insert(Position, AllNodes.remove(N));
714 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary
716 static bool isCommutativeBinOp(unsigned Opcode) {
717 // FIXME: This should get its info from the td file, so that we can include
732 case ISD::ADDE: return true;
733 default: return false;
739 /// CreateStackTemporary - Create a stack temporary, suitable for holding the
740 /// specified value type. If minAlign is specified, the slot size will have
741 /// at least that alignment.
742 SDValue CreateStackTemporary(MVT VT, unsigned minAlign = 1);
744 /// FoldConstantArithmetic -
745 SDValue FoldConstantArithmetic(unsigned Opcode,
747 ConstantSDNode *Cst1,
748 ConstantSDNode *Cst2);
750 /// FoldSetCC - Constant fold a setcc to true or false.
751 SDValue FoldSetCC(MVT VT, SDValue N1,
752 SDValue N2, ISD::CondCode Cond);
754 /// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We
755 /// use this predicate to simplify operations downstream.
756 bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const;
758 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We
759 /// use this predicate to simplify operations downstream. Op and Mask are
760 /// known to be the same type.
761 bool MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth = 0)
764 /// ComputeMaskedBits - Determine which of the bits specified in Mask are
765 /// known to be either zero or one and return them in the KnownZero/KnownOne
766 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit
767 /// processing. Targets can implement the computeMaskedBitsForTargetNode
768 /// method in the TargetLowering class to allow target nodes to be understood.
769 void ComputeMaskedBits(SDValue Op, const APInt &Mask, APInt &KnownZero,
770 APInt &KnownOne, unsigned Depth = 0) const;
772 /// ComputeNumSignBits - Return the number of times the sign bit of the
773 /// register is replicated into the other bits. We know that at least 1 bit
774 /// is always equal to the sign bit (itself), but other cases can give us
775 /// information. For example, immediately after an "SRA X, 2", we know that
776 /// the top 3 bits are all equal to each other, so we return 3. Targets can
777 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
778 /// class to allow target nodes to be understood.
779 unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const;
781 /// isVerifiedDebugInfoDesc - Returns true if the specified SDValue has
782 /// been verified as a debug information descriptor.
783 bool isVerifiedDebugInfoDesc(SDValue Op) const;
785 /// getShuffleScalarElt - Returns the scalar element that will make up the ith
786 /// element of the result of the vector shuffle.
787 SDValue getShuffleScalarElt(const SDNode *N, unsigned Idx);
790 bool RemoveNodeFromCSEMaps(SDNode *N);
791 SDNode *AddNonLeafNodeToCSEMaps(SDNode *N);
792 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos);
793 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2,
795 SDNode *FindModifiedNodeSlot(SDNode *N, const SDValue *Ops, unsigned NumOps,
798 void DeleteNodeNotInCSEMaps(SDNode *N);
800 unsigned getMVTAlignment(MVT MemoryVT) const;
802 void allnodes_clear();
804 // List of non-single value types.
805 std::vector<SDVTList> VTList;
807 // Maps to auto-CSE operations.
808 std::vector<CondCodeSDNode*> CondCodeNodes;
810 std::vector<SDNode*> ValueTypeNodes;
811 std::map<MVT, SDNode*, MVT::compareRawBits> ExtendedValueTypeNodes;
812 StringMap<SDNode*> ExternalSymbols;
813 StringMap<SDNode*> TargetExternalSymbols;
816 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
817 typedef SelectionDAG::allnodes_iterator nodes_iterator;
818 static nodes_iterator nodes_begin(SelectionDAG *G) {
819 return G->allnodes_begin();
821 static nodes_iterator nodes_end(SelectionDAG *G) {
822 return G->allnodes_end();
826 } // end namespace llvm