1 //===-- llvm/CodeGen/SelectionDAG.h - InstSelection DAG ---------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file declares the SelectionDAG class, and transitively defines the
11 // SDNode class and subclasses.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_CODEGEN_SELECTIONDAG_H
16 #define LLVM_CODEGEN_SELECTIONDAG_H
18 #include "llvm/ADT/ilist.h"
19 #include "llvm/ADT/FoldingSet.h"
20 #include "llvm/ADT/StringMap.h"
21 #include "llvm/CodeGen/SelectionDAGNodes.h"
34 class MachineModuleInfo;
35 class MachineFunction;
36 class MachineConstantPoolValue;
37 class FunctionLoweringInfo;
39 template<> 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);
107 SelectionDAG(TargetLowering &tli, FunctionLoweringInfo &fli);
110 /// init - Prepare this SelectionDAG to process code in the given
113 void init(MachineFunction &mf, MachineModuleInfo *mmi);
115 /// clear - Clear state and free memory necessary to make this
116 /// SelectionDAG ready to process a new block.
120 MachineFunction &getMachineFunction() const { return *MF; }
121 const TargetMachine &getTarget() const;
122 TargetLowering &getTargetLoweringInfo() const { return TLI; }
123 FunctionLoweringInfo &getFunctionLoweringInfo() const { return FLI; }
124 MachineModuleInfo *getMachineModuleInfo() const { return MMI; }
126 /// viewGraph - Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
128 void viewGraph(const std::string &Title);
132 std::map<const SDNode *, std::string> NodeGraphAttrs;
135 /// clearGraphAttrs - Clear all previously defined node graph attributes.
136 /// Intended to be used from a debugging tool (eg. gdb).
137 void clearGraphAttrs();
139 /// setGraphAttrs - Set graph attributes for a node. (eg. "color=red".)
141 void setGraphAttrs(const SDNode *N, const char *Attrs);
143 /// getGraphAttrs - Get graph attributes for a node. (eg. "color=red".)
144 /// Used from getNodeAttributes.
145 const std::string getGraphAttrs(const SDNode *N) const;
147 /// setGraphColor - Convenience for setting node color attribute.
149 void setGraphColor(const SDNode *N, const char *Color);
151 typedef ilist<SDNode>::const_iterator allnodes_const_iterator;
152 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
153 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
154 typedef ilist<SDNode>::iterator allnodes_iterator;
155 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
156 allnodes_iterator allnodes_end() { return AllNodes.end(); }
157 ilist<SDNode>::size_type allnodes_size() const {
158 return AllNodes.size();
161 /// getRoot - Return the root tag of the SelectionDAG.
163 const SDValue &getRoot() const { return Root; }
165 /// getEntryNode - Return the token chain corresponding to the entry of the
167 SDValue getEntryNode() const {
168 return SDValue(const_cast<SDNode *>(&EntryNode), 0);
171 /// setRoot - Set the current root tag of the SelectionDAG.
173 const SDValue &setRoot(SDValue N) {
174 assert((!N.getNode() || N.getValueType() == MVT::Other) &&
175 "DAG root value is not a chain!");
179 /// Combine - This iterates over the nodes in the SelectionDAG, folding
180 /// certain types of nodes together, or eliminating superfluous nodes. When
181 /// the AfterLegalize argument is set to 'true', Combine takes care not to
182 /// generate any nodes that will be illegal on the target.
183 void Combine(bool AfterLegalize, AliasAnalysis &AA, bool Fast);
185 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that
186 /// only uses types natively supported by the target.
188 /// Note that this is an involved process that may invalidate pointers into
190 void LegalizeTypes();
192 /// Legalize - This transforms the SelectionDAG into a SelectionDAG that is
193 /// compatible with the target instruction selector, as indicated by the
194 /// TargetLowering object.
196 /// Note that this is an involved process that may invalidate pointers into
200 /// RemoveDeadNodes - This method deletes all unreachable nodes in the
202 void RemoveDeadNodes();
204 /// DeleteNode - Remove the specified node from the system. This node must
205 /// have no referrers.
206 void DeleteNode(SDNode *N);
208 /// getVTList - Return an SDVTList that represents the list of values
210 SDVTList getVTList(MVT VT);
211 SDVTList getVTList(MVT VT1, MVT VT2);
212 SDVTList getVTList(MVT VT1, MVT VT2, MVT VT3);
213 SDVTList getVTList(const MVT *VTs, unsigned NumVTs);
215 /// getNodeValueTypes - These are obsolete, use getVTList instead.
216 const MVT *getNodeValueTypes(MVT VT) {
217 return getVTList(VT).VTs;
219 const MVT *getNodeValueTypes(MVT VT1, MVT VT2) {
220 return getVTList(VT1, VT2).VTs;
222 const MVT *getNodeValueTypes(MVT VT1, MVT VT2, MVT VT3) {
223 return getVTList(VT1, VT2, VT3).VTs;
225 const MVT *getNodeValueTypes(const std::vector<MVT> &vtList) {
226 return getVTList(&vtList[0], (unsigned)vtList.size()).VTs;
230 //===--------------------------------------------------------------------===//
231 // Node creation methods.
233 SDValue getConstant(uint64_t Val, MVT VT, bool isTarget = false);
234 SDValue getConstant(const APInt &Val, MVT VT, bool isTarget = false);
235 SDValue getConstant(const ConstantInt &Val, MVT VT, bool isTarget = false);
236 SDValue getIntPtrConstant(uint64_t Val, bool isTarget = false);
237 SDValue getTargetConstant(uint64_t Val, MVT VT) {
238 return getConstant(Val, VT, true);
240 SDValue getTargetConstant(const APInt &Val, MVT VT) {
241 return getConstant(Val, VT, true);
243 SDValue getTargetConstant(const ConstantInt &Val, MVT VT) {
244 return getConstant(Val, VT, true);
246 SDValue getConstantFP(double Val, MVT VT, bool isTarget = false);
247 SDValue getConstantFP(const APFloat& Val, MVT VT, bool isTarget = false);
248 SDValue getConstantFP(const ConstantFP &CF, MVT VT, bool isTarget = false);
249 SDValue getTargetConstantFP(double Val, MVT VT) {
250 return getConstantFP(Val, VT, true);
252 SDValue getTargetConstantFP(const APFloat& Val, MVT VT) {
253 return getConstantFP(Val, VT, true);
255 SDValue getTargetConstantFP(const ConstantFP &Val, MVT VT) {
256 return getConstantFP(Val, VT, true);
258 SDValue getGlobalAddress(const GlobalValue *GV, MVT VT,
259 int offset = 0, bool isTargetGA = false);
260 SDValue getTargetGlobalAddress(const GlobalValue *GV, MVT VT,
262 return getGlobalAddress(GV, VT, offset, true);
264 SDValue getFrameIndex(int FI, MVT VT, bool isTarget = false);
265 SDValue getTargetFrameIndex(int FI, MVT VT) {
266 return getFrameIndex(FI, VT, true);
268 SDValue getJumpTable(int JTI, MVT VT, bool isTarget = false);
269 SDValue getTargetJumpTable(int JTI, MVT VT) {
270 return getJumpTable(JTI, VT, true);
272 SDValue getConstantPool(Constant *C, MVT VT,
273 unsigned Align = 0, int Offs = 0, bool isT=false);
274 SDValue getTargetConstantPool(Constant *C, MVT VT,
275 unsigned Align = 0, int Offset = 0) {
276 return getConstantPool(C, VT, Align, Offset, true);
278 SDValue getConstantPool(MachineConstantPoolValue *C, MVT VT,
279 unsigned Align = 0, int Offs = 0, bool isT=false);
280 SDValue getTargetConstantPool(MachineConstantPoolValue *C,
281 MVT VT, unsigned Align = 0,
283 return getConstantPool(C, VT, Align, Offset, true);
285 SDValue getBasicBlock(MachineBasicBlock *MBB);
286 SDValue getExternalSymbol(const char *Sym, MVT VT);
287 SDValue getTargetExternalSymbol(const char *Sym, MVT VT);
288 SDValue getArgFlags(ISD::ArgFlagsTy Flags);
289 SDValue getValueType(MVT);
290 SDValue getRegister(unsigned Reg, MVT VT);
291 SDValue getDbgStopPoint(SDValue Root, unsigned Line, unsigned Col,
292 const CompileUnitDesc *CU);
293 SDValue getLabel(unsigned Opcode, SDValue Root, unsigned LabelID);
295 SDValue getCopyToReg(SDValue Chain, unsigned Reg, SDValue N) {
296 return getNode(ISD::CopyToReg, MVT::Other, Chain,
297 getRegister(Reg, N.getValueType()), N);
300 // This version of the getCopyToReg method takes an extra operand, which
301 // indicates that there is potentially an incoming flag value (if Flag is not
302 // null) and that there should be a flag result.
303 SDValue getCopyToReg(SDValue Chain, unsigned Reg, SDValue N,
305 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
306 SDValue Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Flag };
307 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.getNode() ? 4 : 3);
310 // Similar to last getCopyToReg() except parameter Reg is a SDValue
311 SDValue getCopyToReg(SDValue Chain, SDValue Reg, SDValue N,
313 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
314 SDValue Ops[] = { Chain, Reg, N, Flag };
315 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.getNode() ? 4 : 3);
318 SDValue getCopyFromReg(SDValue Chain, unsigned Reg, MVT VT) {
319 const MVT *VTs = getNodeValueTypes(VT, MVT::Other);
320 SDValue Ops[] = { Chain, getRegister(Reg, VT) };
321 return getNode(ISD::CopyFromReg, VTs, 2, Ops, 2);
324 // This version of the getCopyFromReg method takes an extra operand, which
325 // indicates that there is potentially an incoming flag value (if Flag is not
326 // null) and that there should be a flag result.
327 SDValue getCopyFromReg(SDValue Chain, unsigned Reg, MVT VT,
329 const MVT *VTs = getNodeValueTypes(VT, MVT::Other, MVT::Flag);
330 SDValue Ops[] = { Chain, getRegister(Reg, VT), Flag };
331 return getNode(ISD::CopyFromReg, VTs, 3, Ops, Flag.getNode() ? 3 : 2);
334 SDValue getCondCode(ISD::CondCode Cond);
336 /// getZeroExtendInReg - Return the expression required to zero extend the Op
337 /// value assuming it was the smaller SrcTy value.
338 SDValue getZeroExtendInReg(SDValue Op, MVT SrcTy);
340 /// getCALLSEQ_START - Return a new CALLSEQ_START node, which always must have
341 /// a flag result (to ensure it's not CSE'd).
342 SDValue getCALLSEQ_START(SDValue Chain, SDValue Op) {
343 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
344 SDValue Ops[] = { Chain, Op };
345 return getNode(ISD::CALLSEQ_START, VTs, 2, Ops, 2);
348 /// getCALLSEQ_END - Return a new CALLSEQ_END node, which always must have a
349 /// flag result (to ensure it's not CSE'd).
350 SDValue getCALLSEQ_END(SDValue Chain, SDValue Op1, SDValue Op2,
352 SDVTList NodeTys = getVTList(MVT::Other, MVT::Flag);
353 SmallVector<SDValue, 4> Ops;
354 Ops.push_back(Chain);
357 Ops.push_back(InFlag);
358 return getNode(ISD::CALLSEQ_END, NodeTys, &Ops[0],
359 (unsigned)Ops.size() - (InFlag.getNode() == 0 ? 1 : 0));
362 /// getNode - Gets or creates the specified node.
364 SDValue getNode(unsigned Opcode, MVT VT);
365 SDValue getNode(unsigned Opcode, MVT VT, SDValue N);
366 SDValue getNode(unsigned Opcode, MVT VT, SDValue N1, SDValue N2);
367 SDValue getNode(unsigned Opcode, MVT VT,
368 SDValue N1, SDValue N2, SDValue N3);
369 SDValue getNode(unsigned Opcode, MVT VT,
370 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
371 SDValue getNode(unsigned Opcode, MVT VT,
372 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
374 SDValue getNode(unsigned Opcode, MVT VT,
375 const SDValue *Ops, unsigned NumOps);
376 SDValue getNode(unsigned Opcode, MVT VT,
377 const SDUse *Ops, unsigned NumOps);
378 SDValue getNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
379 const SDValue *Ops, unsigned NumOps);
380 SDValue getNode(unsigned Opcode, const MVT *VTs, unsigned NumVTs,
381 const SDValue *Ops, unsigned NumOps);
382 SDValue getNode(unsigned Opcode, SDVTList VTs);
383 SDValue getNode(unsigned Opcode, SDVTList VTs, SDValue N);
384 SDValue getNode(unsigned Opcode, SDVTList VTs, SDValue N1, SDValue N2);
385 SDValue getNode(unsigned Opcode, SDVTList VTs,
386 SDValue N1, SDValue N2, SDValue N3);
387 SDValue getNode(unsigned Opcode, SDVTList VTs,
388 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
389 SDValue getNode(unsigned Opcode, SDVTList VTs,
390 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
392 SDValue getNode(unsigned Opcode, SDVTList VTs,
393 const SDValue *Ops, unsigned NumOps);
395 SDValue getMemcpy(SDValue Chain, SDValue Dst, SDValue Src,
396 SDValue Size, unsigned Align,
398 const Value *DstSV, uint64_t DstSVOff,
399 const Value *SrcSV, uint64_t SrcSVOff);
401 SDValue getMemmove(SDValue Chain, SDValue Dst, SDValue Src,
402 SDValue Size, unsigned Align,
403 const Value *DstSV, uint64_t DstOSVff,
404 const Value *SrcSV, uint64_t SrcSVOff);
406 SDValue getMemset(SDValue Chain, SDValue Dst, SDValue Src,
407 SDValue Size, unsigned Align,
408 const Value *DstSV, uint64_t DstSVOff);
410 /// getSetCC - Helper function to make it easier to build SetCC's if you just
411 /// have an ISD::CondCode instead of an SDValue.
413 SDValue getSetCC(MVT VT, SDValue LHS, SDValue RHS,
414 ISD::CondCode Cond) {
415 return getNode(ISD::SETCC, VT, LHS, RHS, getCondCode(Cond));
418 /// getVSetCC - Helper function to make it easier to build VSetCC's nodes
419 /// if you just have an ISD::CondCode instead of an SDValue.
421 SDValue getVSetCC(MVT VT, SDValue LHS, SDValue RHS,
422 ISD::CondCode Cond) {
423 return getNode(ISD::VSETCC, VT, LHS, RHS, getCondCode(Cond));
426 /// getSelectCC - Helper function to make it easier to build SelectCC's if you
427 /// just have an ISD::CondCode instead of an SDValue.
429 SDValue getSelectCC(SDValue LHS, SDValue RHS,
430 SDValue True, SDValue False, ISD::CondCode Cond) {
431 return getNode(ISD::SELECT_CC, True.getValueType(), LHS, RHS, True, False,
435 /// getVAArg - VAArg produces a result and token chain, and takes a pointer
436 /// and a source value as input.
437 SDValue getVAArg(MVT VT, SDValue Chain, SDValue Ptr,
440 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
442 SDValue getAtomic(unsigned Opcode, SDValue Chain, SDValue Ptr,
443 SDValue Cmp, SDValue Swp, const Value* PtrVal,
444 unsigned Alignment=0);
446 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
448 SDValue getAtomic(unsigned Opcode, SDValue Chain, SDValue Ptr,
449 SDValue Val, const Value* PtrVal,
450 unsigned Alignment = 0);
452 /// getMergeValues - Create a MERGE_VALUES node from the given operands.
453 /// Allowed to return something different (and simpler) if Simplify is true.
454 SDValue getMergeValues(const SDValue *Ops, unsigned NumOps,
455 bool Simplify = true);
457 /// getMergeValues - Create a MERGE_VALUES node from the given types and ops.
458 /// Allowed to return something different (and simpler) if Simplify is true.
459 /// May be faster than the above version if VTs is known and NumOps is large.
460 SDValue getMergeValues(SDVTList VTs, const SDValue *Ops, unsigned NumOps,
461 bool Simplify = true) {
462 if (Simplify && NumOps == 1)
464 return getNode(ISD::MERGE_VALUES, VTs, Ops, NumOps);
467 /// getCall - Create a CALL node from the given information.
469 SDValue getCall(unsigned CallingConv, bool IsVarArgs, bool IsTailCall,
470 SDVTList VTs, const SDValue *Operands, unsigned NumOperands);
472 /// getLoad - Loads are not normal binary operators: their result type is not
473 /// determined by their operands, and they produce a value AND a token chain.
475 SDValue getLoad(MVT VT, SDValue Chain, SDValue Ptr,
476 const Value *SV, int SVOffset, bool isVolatile=false,
477 unsigned Alignment=0);
478 SDValue getExtLoad(ISD::LoadExtType ExtType, MVT VT,
479 SDValue Chain, SDValue Ptr, const Value *SV,
480 int SVOffset, MVT EVT, bool isVolatile=false,
481 unsigned Alignment=0);
482 SDValue getIndexedLoad(SDValue OrigLoad, SDValue Base,
483 SDValue Offset, ISD::MemIndexedMode AM);
484 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
485 MVT VT, SDValue Chain,
486 SDValue Ptr, SDValue Offset,
487 const Value *SV, int SVOffset, MVT EVT,
488 bool isVolatile=false, unsigned Alignment=0);
490 /// getStore - Helper function to build ISD::STORE nodes.
492 SDValue getStore(SDValue Chain, SDValue Val, SDValue Ptr,
493 const Value *SV, int SVOffset, bool isVolatile=false,
494 unsigned Alignment=0);
495 SDValue getTruncStore(SDValue Chain, SDValue Val, SDValue Ptr,
496 const Value *SV, int SVOffset, MVT TVT,
497 bool isVolatile=false, unsigned Alignment=0);
498 SDValue getIndexedStore(SDValue OrigStoe, SDValue Base,
499 SDValue Offset, ISD::MemIndexedMode AM);
501 // getSrcValue - Construct a node to track a Value* through the backend.
502 SDValue getSrcValue(const Value *v);
504 // getMemOperand - Construct a node to track a memory reference
505 // through the backend.
506 SDValue getMemOperand(const MachineMemOperand &MO);
508 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the
509 /// specified operands. If the resultant node already exists in the DAG,
510 /// this does not modify the specified node, instead it returns the node that
511 /// already exists. If the resultant node does not exist in the DAG, the
512 /// input node is returned. As a degenerate case, if you specify the same
513 /// input operands as the node already has, the input node is returned.
514 SDValue UpdateNodeOperands(SDValue N, SDValue Op);
515 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2);
516 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
518 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
519 SDValue Op3, SDValue Op4);
520 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
521 SDValue Op3, SDValue Op4, SDValue Op5);
522 SDValue UpdateNodeOperands(SDValue N,
523 const SDValue *Ops, unsigned NumOps);
525 /// SelectNodeTo - These are used for target selectors to *mutate* the
526 /// specified node to have the specified return type, Target opcode, and
527 /// operands. Note that target opcodes are stored as
528 /// ~TargetOpcode in the node opcode field. The resultant node is returned.
529 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT);
530 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, SDValue Op1);
531 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
532 SDValue Op1, SDValue Op2);
533 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
534 SDValue Op1, SDValue Op2, SDValue Op3);
535 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
536 const SDValue *Ops, unsigned NumOps);
537 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, MVT VT2);
538 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
539 MVT VT2, const SDValue *Ops, unsigned NumOps);
540 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
541 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps);
542 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
543 MVT VT2, SDValue Op1);
544 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
545 MVT VT2, SDValue Op1, SDValue Op2);
546 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
547 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
548 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
549 const SDValue *Ops, unsigned NumOps);
551 /// MorphNodeTo - These *mutate* the specified node to have the specified
552 /// return type, opcode, and operands.
553 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT);
554 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT, SDValue Op1);
555 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
556 SDValue Op1, SDValue Op2);
557 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
558 SDValue Op1, SDValue Op2, SDValue Op3);
559 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
560 const SDValue *Ops, unsigned NumOps);
561 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1, MVT VT2);
562 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
563 MVT VT2, const SDValue *Ops, unsigned NumOps);
564 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
565 MVT VT2, MVT VT3, const SDValue *Ops, unsigned NumOps);
566 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
567 MVT VT2, SDValue Op1);
568 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
569 MVT VT2, SDValue Op1, SDValue Op2);
570 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
571 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
572 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
573 const SDValue *Ops, unsigned NumOps);
575 /// getTargetNode - These are used for target selectors to create a new node
576 /// with specified return type(s), target opcode, and operands.
578 /// Note that getTargetNode returns the resultant node. If there is already a
579 /// node of the specified opcode and operands, it returns that node instead of
581 SDNode *getTargetNode(unsigned Opcode, MVT VT);
582 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1);
583 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDValue Op1, SDValue Op2);
584 SDNode *getTargetNode(unsigned Opcode, MVT VT,
585 SDValue Op1, SDValue Op2, SDValue Op3);
586 SDNode *getTargetNode(unsigned Opcode, MVT VT,
587 const SDValue *Ops, unsigned NumOps);
588 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2);
589 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, SDValue Op1);
590 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
591 MVT VT2, SDValue Op1, SDValue Op2);
592 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
593 MVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
594 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2,
595 const SDValue *Ops, unsigned NumOps);
596 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
597 SDValue Op1, SDValue Op2);
598 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
599 SDValue Op1, SDValue Op2, SDValue Op3);
600 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
601 const SDValue *Ops, unsigned NumOps);
602 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, MVT VT4,
603 const SDValue *Ops, unsigned NumOps);
604 SDNode *getTargetNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
605 const SDValue *Ops, unsigned NumOps);
607 /// getNodeIfExists - Get the specified node if it's already available, or
608 /// else return NULL.
609 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs,
610 const SDValue *Ops, unsigned NumOps);
612 /// DAGUpdateListener - Clients of various APIs that cause global effects on
613 /// the DAG can optionally implement this interface. This allows the clients
614 /// to handle the various sorts of updates that happen.
615 class DAGUpdateListener {
617 virtual ~DAGUpdateListener();
619 /// NodeDeleted - The node N that was deleted and, if E is not null, an
620 /// equivalent node E that replaced it.
621 virtual void NodeDeleted(SDNode *N, SDNode *E) = 0;
623 /// NodeUpdated - The node N that was updated.
624 virtual void NodeUpdated(SDNode *N) = 0;
627 /// RemoveDeadNode - Remove the specified node from the system. If any of its
628 /// operands then becomes dead, remove them as well. Inform UpdateListener
629 /// for each node deleted.
630 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0);
632 /// RemoveDeadNodes - This method deletes the unreachable nodes in the
633 /// given list, and any nodes that become unreachable as a result.
634 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes,
635 DAGUpdateListener *UpdateListener = 0);
637 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
638 /// This can cause recursive merging of nodes in the DAG. Use the first
639 /// version if 'From' is known to have a single result, use the second
640 /// if you have two nodes with identical results, use the third otherwise.
642 /// These methods all take an optional UpdateListener, which (if not null) is
643 /// informed about nodes that are deleted and modified due to recursive
644 /// changes in the dag.
646 void ReplaceAllUsesWith(SDValue From, SDValue Op,
647 DAGUpdateListener *UpdateListener = 0);
648 void ReplaceAllUsesWith(SDNode *From, SDNode *To,
649 DAGUpdateListener *UpdateListener = 0);
650 void ReplaceAllUsesWith(SDNode *From, const SDValue *To,
651 DAGUpdateListener *UpdateListener = 0);
653 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving
654 /// uses of other values produced by From.Val alone.
655 void ReplaceAllUsesOfValueWith(SDValue From, SDValue To,
656 DAGUpdateListener *UpdateListener = 0);
658 /// ReplaceAllUsesOfValuesWith - Like ReplaceAllUsesOfValueWith, but
659 /// for multiple values at once. This correctly handles the case where
660 /// there is an overlap between the From values and the To values.
661 void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To,
663 DAGUpdateListener *UpdateListener = 0);
665 /// AssignTopologicalOrder - Assign a unique node id for each node in the DAG
666 /// based on their topological order. It returns the maximum id and a vector
667 /// of the SDNodes* in assigned order by reference.
668 unsigned AssignTopologicalOrder(std::vector<SDNode*> &TopOrder);
670 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary
672 static bool isCommutativeBinOp(unsigned Opcode) {
673 // FIXME: This should get its info from the td file, so that we can include
688 case ISD::ADDE: return true;
689 default: return false;
695 /// CreateStackTemporary - Create a stack temporary, suitable for holding the
696 /// specified value type. If minAlign is specified, the slot size will have
697 /// at least that alignment.
698 SDValue CreateStackTemporary(MVT VT, unsigned minAlign = 1);
700 /// FoldSetCC - Constant fold a setcc to true or false.
701 SDValue FoldSetCC(MVT VT, SDValue N1,
702 SDValue N2, ISD::CondCode Cond);
704 /// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We
705 /// use this predicate to simplify operations downstream.
706 bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const;
708 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We
709 /// use this predicate to simplify operations downstream. Op and Mask are
710 /// known to be the same type.
711 bool MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth = 0)
714 /// ComputeMaskedBits - Determine which of the bits specified in Mask are
715 /// known to be either zero or one and return them in the KnownZero/KnownOne
716 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit
717 /// processing. Targets can implement the computeMaskedBitsForTargetNode
718 /// method in the TargetLowering class to allow target nodes to be understood.
719 void ComputeMaskedBits(SDValue Op, const APInt &Mask, APInt &KnownZero,
720 APInt &KnownOne, unsigned Depth = 0) const;
722 /// ComputeNumSignBits - Return the number of times the sign bit of the
723 /// register is replicated into the other bits. We know that at least 1 bit
724 /// is always equal to the sign bit (itself), but other cases can give us
725 /// information. For example, immediately after an "SRA X, 2", we know that
726 /// the top 3 bits are all equal to each other, so we return 3. Targets can
727 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
728 /// class to allow target nodes to be understood.
729 unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const;
731 /// isVerifiedDebugInfoDesc - Returns true if the specified SDValue has
732 /// been verified as a debug information descriptor.
733 bool isVerifiedDebugInfoDesc(SDValue Op) const;
735 /// getShuffleScalarElt - Returns the scalar element that will make up the ith
736 /// element of the result of the vector shuffle.
737 SDValue getShuffleScalarElt(const SDNode *N, unsigned Idx);
740 bool RemoveNodeFromCSEMaps(SDNode *N);
741 SDNode *AddNonLeafNodeToCSEMaps(SDNode *N);
742 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos);
743 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2,
745 SDNode *FindModifiedNodeSlot(SDNode *N, const SDValue *Ops, unsigned NumOps,
748 void DeleteNodeNotInCSEMaps(SDNode *N);
750 unsigned getMVTAlignment(MVT MemoryVT) const;
752 void allnodes_clear();
754 // List of non-single value types.
755 std::vector<SDVTList> VTList;
757 // Maps to auto-CSE operations.
758 std::vector<CondCodeSDNode*> CondCodeNodes;
760 std::vector<SDNode*> ValueTypeNodes;
761 std::map<MVT, SDNode*, MVT::compareRawBits> ExtendedValueTypeNodes;
762 StringMap<SDNode*> ExternalSymbols;
763 StringMap<SDNode*> TargetExternalSymbols;
766 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
767 typedef SelectionDAG::allnodes_iterator nodes_iterator;
768 static nodes_iterator nodes_begin(SelectionDAG *G) {
769 return G->allnodes_begin();
771 static nodes_iterator nodes_end(SelectionDAG *G) {
772 return G->allnodes_end();
776 } // end namespace llvm