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 &);
57 /// SelectionDAG class - This is used to represent a portion of an LLVM function
58 /// in a low-level Data Dependence DAG representation suitable for instruction
59 /// selection. This DAG is constructed as the first step of instruction
60 /// selection in order to allow implementation of machine specific optimizations
61 /// and code simplifications.
63 /// The representation used by the SelectionDAG is a target-independent
64 /// representation, which has some similarities to the GCC RTL representation,
65 /// but is significantly more simple, powerful, and is a graph form instead of a
71 FunctionLoweringInfo &FLI;
72 MachineModuleInfo *MMI;
74 /// EntryNode - The starting token.
77 /// Root - The root of the entire DAG.
80 /// AllNodes - A linked list of nodes in the current DAG.
81 ilist<SDNode> AllNodes;
83 /// NodeAllocatorType - The AllocatorType for allocating SDNodes. We use
84 /// pool allocation with recycling.
85 typedef RecyclingAllocator<BumpPtrAllocator, SDNode, sizeof(LargestSDNode),
86 AlignOf<MostAlignedSDNode>::Alignment>
89 /// NodeAllocator - Pool allocation for nodes.
90 NodeAllocatorType NodeAllocator;
92 /// CSEMap - This structure is used to memoize nodes, automatically performing
93 /// CSE with existing nodes with a duplicate is requested.
94 FoldingSet<SDNode> CSEMap;
96 /// OperandAllocator - Pool allocation for machine-opcode SDNode operands.
97 BumpPtrAllocator OperandAllocator;
99 /// Allocator - Pool allocation for misc. objects that are created once per
101 BumpPtrAllocator Allocator;
103 /// VerifyNode - Sanity check the given node. Aborts if it is invalid.
104 void VerifyNode(SDNode *N);
106 /// setGraphColorHelper - Implementation of setSubgraphColor.
107 /// Return whether we had to truncate the search.
109 bool setSubgraphColorHelper(SDNode *N, const char *Color, DenseSet<SDNode *> &visited,
110 int level, bool &printed);
113 SelectionDAG(TargetLowering &tli, FunctionLoweringInfo &fli);
116 /// init - Prepare this SelectionDAG to process code in the given
119 void init(MachineFunction &mf, MachineModuleInfo *mmi);
121 /// clear - Clear state and free memory necessary to make this
122 /// SelectionDAG ready to process a new block.
126 MachineFunction &getMachineFunction() const { return *MF; }
127 const TargetMachine &getTarget() const;
128 TargetLowering &getTargetLoweringInfo() const { return TLI; }
129 FunctionLoweringInfo &getFunctionLoweringInfo() const { return FLI; }
130 MachineModuleInfo *getMachineModuleInfo() const { return MMI; }
132 /// viewGraph - Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
134 void viewGraph(const std::string &Title);
138 std::map<const SDNode *, std::string> NodeGraphAttrs;
141 /// clearGraphAttrs - Clear all previously defined node graph attributes.
142 /// Intended to be used from a debugging tool (eg. gdb).
143 void clearGraphAttrs();
145 /// setGraphAttrs - Set graph attributes for a node. (eg. "color=red".)
147 void setGraphAttrs(const SDNode *N, const char *Attrs);
149 /// getGraphAttrs - Get graph attributes for a node. (eg. "color=red".)
150 /// Used from getNodeAttributes.
151 const std::string getGraphAttrs(const SDNode *N) const;
153 /// setGraphColor - Convenience for setting node color attribute.
155 void setGraphColor(const SDNode *N, const char *Color);
157 /// setGraphColor - Convenience for setting subgraph color attribute.
159 void setSubgraphColor(SDNode *N, const char *Color);
161 typedef ilist<SDNode>::const_iterator allnodes_const_iterator;
162 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
163 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
164 typedef ilist<SDNode>::iterator allnodes_iterator;
165 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
166 allnodes_iterator allnodes_end() { return AllNodes.end(); }
167 ilist<SDNode>::size_type allnodes_size() const {
168 return AllNodes.size();
171 /// getRoot - Return the root tag of the SelectionDAG.
173 const SDValue &getRoot() const { return Root; }
175 /// getEntryNode - Return the token chain corresponding to the entry of the
177 SDValue getEntryNode() const {
178 return SDValue(const_cast<SDNode *>(&EntryNode), 0);
181 /// setRoot - Set the current root tag of the SelectionDAG.
183 const SDValue &setRoot(SDValue N) {
184 assert((!N.getNode() || N.getValueType() == MVT::Other) &&
185 "DAG root value is not a chain!");
189 /// Combine - This iterates over the nodes in the SelectionDAG, folding
190 /// certain types of nodes together, or eliminating superfluous nodes. When
191 /// the AfterLegalize argument is set to 'true', Combine takes care not to
192 /// generate any nodes that will be illegal on the target.
193 void Combine(bool AfterLegalize, AliasAnalysis &AA, bool Fast);
195 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that
196 /// only uses types natively supported by the target.
198 /// Note that this is an involved process that may invalidate pointers into
200 void LegalizeTypes();
202 /// Legalize - This transforms the SelectionDAG into a SelectionDAG that is
203 /// compatible with the target instruction selector, as indicated by the
204 /// TargetLowering object.
206 /// Note that this is an involved process that may invalidate pointers into
210 /// RemoveDeadNodes - This method deletes all unreachable nodes in the
212 void RemoveDeadNodes();
214 /// DeleteNode - Remove the specified node from the system. This node must
215 /// have no referrers.
216 void DeleteNode(SDNode *N);
218 /// getVTList - Return an SDVTList that represents the list of values
220 SDVTList getVTList(MVT VT);
221 SDVTList getVTList(MVT VT1, MVT VT2);
222 SDVTList getVTList(MVT VT1, MVT VT2, MVT VT3);
223 SDVTList getVTList(const MVT *VTs, unsigned NumVTs);
225 /// getNodeValueTypes - These are obsolete, use getVTList instead.
226 const MVT *getNodeValueTypes(MVT VT) {
227 return getVTList(VT).VTs;
229 const MVT *getNodeValueTypes(MVT VT1, MVT VT2) {
230 return getVTList(VT1, VT2).VTs;
232 const MVT *getNodeValueTypes(MVT VT1, MVT VT2, MVT VT3) {
233 return getVTList(VT1, VT2, VT3).VTs;
235 const MVT *getNodeValueTypes(const std::vector<MVT> &vtList) {
236 return getVTList(&vtList[0], (unsigned)vtList.size()).VTs;
240 //===--------------------------------------------------------------------===//
241 // Node creation methods.
243 SDValue getConstant(uint64_t Val, MVT VT, bool isTarget = false);
244 SDValue getConstant(const APInt &Val, MVT VT, bool isTarget = false);
245 SDValue getConstant(const ConstantInt &Val, MVT VT, bool isTarget = false);
246 SDValue getIntPtrConstant(uint64_t Val, bool isTarget = false);
247 SDValue getTargetConstant(uint64_t Val, MVT VT) {
248 return getConstant(Val, VT, true);
250 SDValue getTargetConstant(const APInt &Val, MVT VT) {
251 return getConstant(Val, VT, true);
253 SDValue getTargetConstant(const ConstantInt &Val, MVT VT) {
254 return getConstant(Val, VT, true);
256 SDValue getConstantFP(double Val, MVT VT, bool isTarget = false);
257 SDValue getConstantFP(const APFloat& Val, MVT VT, bool isTarget = false);
258 SDValue getConstantFP(const ConstantFP &CF, MVT VT, bool isTarget = false);
259 SDValue getTargetConstantFP(double Val, MVT VT) {
260 return getConstantFP(Val, VT, true);
262 SDValue getTargetConstantFP(const APFloat& Val, MVT VT) {
263 return getConstantFP(Val, VT, true);
265 SDValue getTargetConstantFP(const ConstantFP &Val, MVT VT) {
266 return getConstantFP(Val, VT, true);
268 SDValue getGlobalAddress(const GlobalValue *GV, MVT VT,
269 int64_t offset = 0, bool isTargetGA = false);
270 SDValue getTargetGlobalAddress(const GlobalValue *GV, MVT VT,
271 int64_t offset = 0) {
272 return getGlobalAddress(GV, VT, offset, true);
274 SDValue getFrameIndex(int FI, MVT VT, bool isTarget = false);
275 SDValue getTargetFrameIndex(int FI, MVT VT) {
276 return getFrameIndex(FI, VT, true);
278 SDValue getJumpTable(int JTI, MVT VT, bool isTarget = false);
279 SDValue getTargetJumpTable(int JTI, MVT VT) {
280 return getJumpTable(JTI, VT, true);
282 SDValue getConstantPool(Constant *C, MVT VT,
283 unsigned Align = 0, int Offs = 0, bool isT=false);
284 SDValue getTargetConstantPool(Constant *C, MVT VT,
285 unsigned Align = 0, int Offset = 0) {
286 return getConstantPool(C, VT, Align, Offset, true);
288 SDValue getConstantPool(MachineConstantPoolValue *C, MVT VT,
289 unsigned Align = 0, int Offs = 0, bool isT=false);
290 SDValue getTargetConstantPool(MachineConstantPoolValue *C,
291 MVT VT, unsigned Align = 0,
293 return getConstantPool(C, VT, Align, Offset, true);
295 SDValue getBasicBlock(MachineBasicBlock *MBB);
296 SDValue getExternalSymbol(const char *Sym, MVT VT);
297 SDValue getTargetExternalSymbol(const char *Sym, MVT VT);
298 SDValue getArgFlags(ISD::ArgFlagsTy Flags);
299 SDValue getValueType(MVT);
300 SDValue getRegister(unsigned Reg, MVT VT);
301 SDValue getDbgStopPoint(SDValue Root, unsigned Line, unsigned Col,
302 const CompileUnitDesc *CU);
303 SDValue getLabel(unsigned Opcode, SDValue Root, unsigned LabelID);
305 SDValue getCopyToReg(SDValue Chain, unsigned Reg, SDValue N) {
306 return getNode(ISD::CopyToReg, MVT::Other, Chain,
307 getRegister(Reg, N.getValueType()), N);
310 // This version of the getCopyToReg method takes an extra operand, which
311 // indicates that there is potentially an incoming flag value (if Flag is not
312 // null) and that there should be a flag result.
313 SDValue getCopyToReg(SDValue Chain, unsigned Reg, SDValue N,
315 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
316 SDValue Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Flag };
317 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.getNode() ? 4 : 3);
320 // Similar to last getCopyToReg() except parameter Reg is a SDValue
321 SDValue getCopyToReg(SDValue Chain, SDValue Reg, SDValue N,
323 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
324 SDValue Ops[] = { Chain, Reg, N, Flag };
325 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.getNode() ? 4 : 3);
328 SDValue getCopyFromReg(SDValue Chain, unsigned Reg, MVT VT) {
329 const MVT *VTs = getNodeValueTypes(VT, MVT::Other);
330 SDValue Ops[] = { Chain, getRegister(Reg, VT) };
331 return getNode(ISD::CopyFromReg, VTs, 2, Ops, 2);
334 // This version of the getCopyFromReg method takes an extra operand, which
335 // indicates that there is potentially an incoming flag value (if Flag is not
336 // null) and that there should be a flag result.
337 SDValue getCopyFromReg(SDValue Chain, unsigned Reg, MVT VT,
339 const MVT *VTs = getNodeValueTypes(VT, MVT::Other, MVT::Flag);
340 SDValue Ops[] = { Chain, getRegister(Reg, VT), Flag };
341 return getNode(ISD::CopyFromReg, VTs, 3, Ops, Flag.getNode() ? 3 : 2);
344 SDValue getCondCode(ISD::CondCode Cond);
346 /// getZeroExtendInReg - Return the expression required to zero extend the Op
347 /// value assuming it was the smaller SrcTy value.
348 SDValue getZeroExtendInReg(SDValue Op, MVT SrcTy);
350 /// getCALLSEQ_START - Return a new CALLSEQ_START node, which always must have
351 /// a flag result (to ensure it's not CSE'd).
352 SDValue getCALLSEQ_START(SDValue Chain, SDValue Op) {
353 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
354 SDValue Ops[] = { Chain, Op };
355 return getNode(ISD::CALLSEQ_START, VTs, 2, Ops, 2);
358 /// getCALLSEQ_END - Return a new CALLSEQ_END node, which always must have a
359 /// flag result (to ensure it's not CSE'd).
360 SDValue getCALLSEQ_END(SDValue Chain, SDValue Op1, SDValue Op2,
362 SDVTList NodeTys = getVTList(MVT::Other, MVT::Flag);
363 SmallVector<SDValue, 4> Ops;
364 Ops.push_back(Chain);
367 Ops.push_back(InFlag);
368 return getNode(ISD::CALLSEQ_END, NodeTys, &Ops[0],
369 (unsigned)Ops.size() - (InFlag.getNode() == 0 ? 1 : 0));
372 /// getNode - Gets or creates the specified node.
374 SDValue getNode(unsigned Opcode, MVT VT);
375 SDValue getNode(unsigned Opcode, MVT VT, SDValue N);
376 SDValue getNode(unsigned Opcode, MVT VT, SDValue N1, SDValue N2);
377 SDValue getNode(unsigned Opcode, MVT VT,
378 SDValue N1, SDValue N2, SDValue N3);
379 SDValue getNode(unsigned Opcode, MVT VT,
380 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
381 SDValue getNode(unsigned Opcode, MVT VT,
382 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
384 SDValue getNode(unsigned Opcode, MVT VT,
385 const SDValue *Ops, unsigned NumOps);
386 SDValue getNode(unsigned Opcode, MVT VT,
387 const SDUse *Ops, unsigned NumOps);
388 SDValue getNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
389 const SDValue *Ops, unsigned NumOps);
390 SDValue getNode(unsigned Opcode, const MVT *VTs, unsigned NumVTs,
391 const SDValue *Ops, unsigned NumOps);
392 SDValue getNode(unsigned Opcode, SDVTList VTs);
393 SDValue getNode(unsigned Opcode, SDVTList VTs, SDValue N);
394 SDValue getNode(unsigned Opcode, SDVTList VTs, SDValue N1, SDValue N2);
395 SDValue getNode(unsigned Opcode, SDVTList VTs,
396 SDValue N1, SDValue N2, SDValue N3);
397 SDValue getNode(unsigned Opcode, SDVTList VTs,
398 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
399 SDValue getNode(unsigned Opcode, SDVTList VTs,
400 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
402 SDValue getNode(unsigned Opcode, SDVTList VTs,
403 const SDValue *Ops, unsigned NumOps);
405 SDValue getMemcpy(SDValue Chain, SDValue Dst, SDValue Src,
406 SDValue Size, unsigned Align,
408 const Value *DstSV, uint64_t DstSVOff,
409 const Value *SrcSV, uint64_t SrcSVOff);
411 SDValue getMemmove(SDValue Chain, SDValue Dst, SDValue Src,
412 SDValue Size, unsigned Align,
413 const Value *DstSV, uint64_t DstOSVff,
414 const Value *SrcSV, uint64_t SrcSVOff);
416 SDValue getMemset(SDValue Chain, SDValue Dst, SDValue Src,
417 SDValue Size, unsigned Align,
418 const Value *DstSV, uint64_t DstSVOff);
420 /// getSetCC - Helper function to make it easier to build SetCC's if you just
421 /// have an ISD::CondCode instead of an SDValue.
423 SDValue getSetCC(MVT VT, SDValue LHS, SDValue RHS,
424 ISD::CondCode Cond) {
425 return getNode(ISD::SETCC, VT, LHS, RHS, getCondCode(Cond));
428 /// getVSetCC - Helper function to make it easier to build VSetCC's nodes
429 /// if you just have an ISD::CondCode instead of an SDValue.
431 SDValue getVSetCC(MVT VT, SDValue LHS, SDValue RHS,
432 ISD::CondCode Cond) {
433 return getNode(ISD::VSETCC, VT, LHS, RHS, getCondCode(Cond));
436 /// getSelectCC - Helper function to make it easier to build SelectCC's if you
437 /// just have an ISD::CondCode instead of an SDValue.
439 SDValue getSelectCC(SDValue LHS, SDValue RHS,
440 SDValue True, SDValue False, ISD::CondCode Cond) {
441 return getNode(ISD::SELECT_CC, True.getValueType(), LHS, RHS, True, False,
445 /// getVAArg - VAArg produces a result and token chain, and takes a pointer
446 /// and a source value as input.
447 SDValue getVAArg(MVT VT, SDValue Chain, SDValue Ptr,
450 /// getAtomic - Gets a node for an atomic op, produces result and chain and
452 SDValue getAtomic(unsigned Opcode, SDValue Chain, SDValue Ptr,
453 SDValue Cmp, SDValue Swp, const Value* PtrVal,
454 unsigned Alignment=0);
456 /// getAtomic - Gets a node for an atomic op, produces result and chain and
457 /// takes 2 operands.
458 SDValue getAtomic(unsigned Opcode, SDValue Chain, SDValue Ptr,
459 SDValue Val, const Value* PtrVal,
460 unsigned Alignment = 0);
462 /// getMemIntrinsicNode - Creates a MemIntrinsicNode that may produce a
463 /// result and takes a list of operands.
464 SDValue getMemIntrinsicNode(unsigned Opcode,
465 const MVT *VTs, unsigned NumVTs,
466 const SDValue *Ops, unsigned NumOps,
467 MVT MemVT, const Value *srcValue, int SVOff,
468 unsigned Align = 0, bool Vol = false,
469 bool ReadMem = true, bool WriteMem = true);
471 SDValue getMemIntrinsicNode(unsigned Opcode, SDVTList VTList,
472 const SDValue *Ops, unsigned NumOps,
473 MVT MemVT, const Value *srcValue, int SVOff,
474 unsigned Align = 0, bool Vol = false,
475 bool ReadMem = true, bool WriteMem = true);
477 /// getMergeValues - Create a MERGE_VALUES node from the given operands.
478 /// Allowed to return something different (and simpler) if Simplify is true.
479 SDValue getMergeValues(const SDValue *Ops, unsigned NumOps,
480 bool Simplify = true);
482 /// getMergeValues - Create a MERGE_VALUES node from the given types and ops.
483 /// Allowed to return something different (and simpler) if Simplify is true.
484 /// May be faster than the above version if VTs is known and NumOps is large.
485 SDValue getMergeValues(SDVTList VTs, const SDValue *Ops, unsigned NumOps,
486 bool Simplify = true) {
487 if (Simplify && NumOps == 1)
489 return getNode(ISD::MERGE_VALUES, VTs, Ops, NumOps);
492 /// getCall - Create a CALL node from the given information.
494 SDValue getCall(unsigned CallingConv, bool IsVarArgs, bool IsTailCall,
495 bool isInreg, SDVTList VTs, const SDValue *Operands,
496 unsigned NumOperands);
498 /// getLoad - Loads are not normal binary operators: their result type is not
499 /// determined by their operands, and they produce a value AND a token chain.
501 SDValue getLoad(MVT VT, SDValue Chain, SDValue Ptr,
502 const Value *SV, int SVOffset, bool isVolatile=false,
503 unsigned Alignment=0);
504 SDValue getExtLoad(ISD::LoadExtType ExtType, MVT VT,
505 SDValue Chain, SDValue Ptr, const Value *SV,
506 int SVOffset, MVT EVT, bool isVolatile=false,
507 unsigned Alignment=0);
508 SDValue getIndexedLoad(SDValue OrigLoad, SDValue Base,
509 SDValue Offset, ISD::MemIndexedMode AM);
510 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
511 MVT VT, SDValue Chain,
512 SDValue Ptr, SDValue Offset,
513 const Value *SV, int SVOffset, MVT EVT,
514 bool isVolatile=false, unsigned Alignment=0);
516 /// getStore - Helper function to build ISD::STORE nodes.
518 SDValue getStore(SDValue Chain, SDValue Val, SDValue Ptr,
519 const Value *SV, int SVOffset, bool isVolatile=false,
520 unsigned Alignment=0);
521 SDValue getTruncStore(SDValue Chain, SDValue Val, SDValue Ptr,
522 const Value *SV, int SVOffset, MVT TVT,
523 bool isVolatile=false, unsigned Alignment=0);
524 SDValue getIndexedStore(SDValue OrigStoe, SDValue Base,
525 SDValue Offset, ISD::MemIndexedMode AM);
527 // getSrcValue - Construct a node to track a Value* through the backend.
528 SDValue getSrcValue(const Value *v);
530 // getMemOperand - Construct a node to track a memory reference
531 // through the backend.
532 SDValue getMemOperand(const MachineMemOperand &MO);
534 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the
535 /// specified operands. If the resultant node already exists in the DAG,
536 /// this does not modify the specified node, instead it returns the node that
537 /// already exists. If the resultant node does not exist in the DAG, the
538 /// input node is returned. As a degenerate case, if you specify the same
539 /// input operands as the node already has, the input node is returned.
540 SDValue UpdateNodeOperands(SDValue N, SDValue Op);
541 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2);
542 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
544 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
545 SDValue Op3, SDValue Op4);
546 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
547 SDValue Op3, SDValue Op4, SDValue Op5);
548 SDValue UpdateNodeOperands(SDValue N,
549 const SDValue *Ops, unsigned NumOps);
551 /// SelectNodeTo - These are used for target selectors to *mutate* the
552 /// specified node to have the specified return type, Target opcode, and
553 /// operands. Note that target opcodes are stored as
554 /// ~TargetOpcode in the node opcode field. The resultant node is returned.
555 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT);
556 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, SDValue Op1);
557 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
558 SDValue Op1, SDValue Op2);
559 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
560 SDValue Op1, SDValue Op2, SDValue Op3);
561 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
562 const SDValue *Ops, unsigned NumOps);
563 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, MVT VT2);
564 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
565 MVT VT2, const SDValue *Ops, unsigned NumOps);
566 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
567 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps);
568 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
569 MVT VT2, SDValue Op1);
570 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
571 MVT VT2, SDValue Op1, SDValue Op2);
572 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
573 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
574 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
575 const SDValue *Ops, unsigned NumOps);
577 /// MorphNodeTo - These *mutate* the specified node to have the specified
578 /// return type, opcode, and operands.
579 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT);
580 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT, SDValue Op1);
581 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
582 SDValue Op1, SDValue Op2);
583 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
584 SDValue Op1, SDValue Op2, SDValue Op3);
585 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
586 const SDValue *Ops, unsigned NumOps);
587 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1, MVT VT2);
588 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
589 MVT VT2, const SDValue *Ops, unsigned NumOps);
590 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
591 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps);
592 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
593 MVT VT2, SDValue Op1);
594 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
595 MVT VT2, SDValue Op1, SDValue Op2);
596 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
597 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
598 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
599 const SDValue *Ops, unsigned NumOps);
601 /// getTargetNode - These are used for target selectors to create a new node
602 /// with specified return type(s), target opcode, and operands.
604 /// Note that getTargetNode returns the resultant node. If there is already a
605 /// node of the specified opcode and operands, it returns that node instead of
607 SDNode *getTargetNode(unsigned Opcode, MVT VT);
608 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1);
609 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1, SDValue Op2);
610 SDNode *getTargetNode(unsigned Opcode, MVT VT,
611 SDValue Op1, SDValue Op2, SDValue Op3);
612 SDNode *getTargetNode(unsigned Opcode, MVT VT,
613 const SDValue *Ops, unsigned NumOps);
614 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2);
615 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, SDValue Op1);
616 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
617 MVT VT2, SDValue Op1, SDValue Op2);
618 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
619 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
620 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2,
621 const SDValue *Ops, unsigned NumOps);
622 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
623 SDValue Op1, SDValue Op2);
624 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
625 SDValue Op1, SDValue Op2, SDValue Op3);
626 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
627 const SDValue *Ops, unsigned NumOps);
628 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, MVT VT4,
629 const SDValue *Ops, unsigned NumOps);
630 SDNode *getTargetNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
631 const SDValue *Ops, unsigned NumOps);
633 /// getNodeIfExists - Get the specified node if it's already available, or
634 /// else return NULL.
635 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs,
636 const SDValue *Ops, unsigned NumOps);
638 /// DAGUpdateListener - Clients of various APIs that cause global effects on
639 /// the DAG can optionally implement this interface. This allows the clients
640 /// to handle the various sorts of updates that happen.
641 class DAGUpdateListener {
643 virtual ~DAGUpdateListener();
645 /// NodeDeleted - The node N that was deleted and, if E is not null, an
646 /// equivalent node E that replaced it.
647 virtual void NodeDeleted(SDNode *N, SDNode *E) = 0;
649 /// NodeUpdated - The node N that was updated.
650 virtual void NodeUpdated(SDNode *N) = 0;
653 /// RemoveDeadNode - Remove the specified node from the system. If any of its
654 /// operands then becomes dead, remove them as well. Inform UpdateListener
655 /// for each node deleted.
656 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0);
658 /// RemoveDeadNodes - This method deletes the unreachable nodes in the
659 /// given list, and any nodes that become unreachable as a result.
660 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes,
661 DAGUpdateListener *UpdateListener = 0);
663 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
664 /// This can cause recursive merging of nodes in the DAG. Use the first
665 /// version if 'From' is known to have a single result, use the second
666 /// if you have two nodes with identical results, use the third otherwise.
668 /// These methods all take an optional UpdateListener, which (if not null) is
669 /// informed about nodes that are deleted and modified due to recursive
670 /// changes in the dag.
672 void ReplaceAllUsesWith(SDValue From, SDValue Op,
673 DAGUpdateListener *UpdateListener = 0);
674 void ReplaceAllUsesWith(SDNode *From, SDNode *To,
675 DAGUpdateListener *UpdateListener = 0);
676 void ReplaceAllUsesWith(SDNode *From, const SDValue *To,
677 DAGUpdateListener *UpdateListener = 0);
679 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving
680 /// uses of other values produced by From.Val alone.
681 void ReplaceAllUsesOfValueWith(SDValue From, SDValue To,
682 DAGUpdateListener *UpdateListener = 0);
684 /// ReplaceAllUsesOfValuesWith - Like ReplaceAllUsesOfValueWith, but
685 /// for multiple values at once. This correctly handles the case where
686 /// there is an overlap between the From values and the To values.
687 void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To,
689 DAGUpdateListener *UpdateListener = 0);
691 /// AssignTopologicalOrder - Topological-sort the AllNodes list and a
692 /// assign a unique node id for each node in the DAG based on their
693 /// topological order. Returns the number of nodes.
694 unsigned AssignTopologicalOrder();
696 /// RepositionNode - Move node N in the AllNodes list to be immediately
697 /// before the given iterator Position. This may be used to update the
698 /// topological ordering when the list of nodes is modified.
699 void RepositionNode(allnodes_iterator Position, SDNode *N) {
700 AllNodes.insert(Position, AllNodes.remove(N));
703 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary
705 static bool isCommutativeBinOp(unsigned Opcode) {
706 // FIXME: This should get its info from the td file, so that we can include
721 case ISD::ADDE: return true;
722 default: return false;
728 /// CreateStackTemporary - Create a stack temporary, suitable for holding the
729 /// specified value type. If minAlign is specified, the slot size will have
730 /// at least that alignment.
731 SDValue CreateStackTemporary(MVT VT, unsigned minAlign = 1);
733 /// FoldConstantArithmetic -
734 SDValue FoldConstantArithmetic(unsigned Opcode,
736 ConstantSDNode *Cst1,
737 ConstantSDNode *Cst2);
739 /// FoldSetCC - Constant fold a setcc to true or false.
740 SDValue FoldSetCC(MVT VT, SDValue N1,
741 SDValue N2, ISD::CondCode Cond);
743 /// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We
744 /// use this predicate to simplify operations downstream.
745 bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const;
747 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We
748 /// use this predicate to simplify operations downstream. Op and Mask are
749 /// known to be the same type.
750 bool MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth = 0)
753 /// ComputeMaskedBits - Determine which of the bits specified in Mask are
754 /// known to be either zero or one and return them in the KnownZero/KnownOne
755 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit
756 /// processing. Targets can implement the computeMaskedBitsForTargetNode
757 /// method in the TargetLowering class to allow target nodes to be understood.
758 void ComputeMaskedBits(SDValue Op, const APInt &Mask, APInt &KnownZero,
759 APInt &KnownOne, unsigned Depth = 0) const;
761 /// ComputeNumSignBits - Return the number of times the sign bit of the
762 /// register is replicated into the other bits. We know that at least 1 bit
763 /// is always equal to the sign bit (itself), but other cases can give us
764 /// information. For example, immediately after an "SRA X, 2", we know that
765 /// the top 3 bits are all equal to each other, so we return 3. Targets can
766 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
767 /// class to allow target nodes to be understood.
768 unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const;
770 /// isVerifiedDebugInfoDesc - Returns true if the specified SDValue has
771 /// been verified as a debug information descriptor.
772 bool isVerifiedDebugInfoDesc(SDValue Op) const;
774 /// getShuffleScalarElt - Returns the scalar element that will make up the ith
775 /// element of the result of the vector shuffle.
776 SDValue getShuffleScalarElt(const SDNode *N, unsigned Idx);
779 bool RemoveNodeFromCSEMaps(SDNode *N);
780 SDNode *AddNonLeafNodeToCSEMaps(SDNode *N);
781 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos);
782 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2,
784 SDNode *FindModifiedNodeSlot(SDNode *N, const SDValue *Ops, unsigned NumOps,
787 void DeleteNodeNotInCSEMaps(SDNode *N);
789 unsigned getMVTAlignment(MVT MemoryVT) const;
791 void allnodes_clear();
793 // List of non-single value types.
794 std::vector<SDVTList> VTList;
796 // Maps to auto-CSE operations.
797 std::vector<CondCodeSDNode*> CondCodeNodes;
799 std::vector<SDNode*> ValueTypeNodes;
800 std::map<MVT, SDNode*, MVT::compareRawBits> ExtendedValueTypeNodes;
801 StringMap<SDNode*> ExternalSymbols;
802 StringMap<SDNode*> TargetExternalSymbols;
805 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
806 typedef SelectionDAG::allnodes_iterator nodes_iterator;
807 static nodes_iterator nodes_begin(SelectionDAG *G) {
808 return G->allnodes_begin();
810 static nodes_iterator nodes_end(SelectionDAG *G) {
811 return G->allnodes_end();
815 } // end namespace llvm