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/StringMap.h"
21 #include "llvm/CodeGen/SelectionDAGNodes.h"
22 #include "llvm/Support/RecyclingAllocator.h"
23 #include "llvm/Target/TargetMachine.h"
33 class FunctionLoweringInfo;
34 class MachineConstantPoolValue;
35 class MachineFunction;
36 class MachineModuleInfo;
42 template<> struct ilist_traits<SDNode> : public ilist_default_traits<SDNode> {
44 mutable ilist_half_node<SDNode> Sentinel;
46 SDNode *createSentinel() const {
47 return static_cast<SDNode*>(&Sentinel);
49 static void destroySentinel(SDNode *) {}
51 SDNode *provideInitialHead() const { return createSentinel(); }
52 SDNode *ensureHead(SDNode*) const { return createSentinel(); }
53 static void noteHead(SDNode*, SDNode*) {}
55 static void deleteNode(SDNode *) {
56 assert(0 && "ilist_traits<SDNode> shouldn't see a deleteNode call!");
59 static void createNode(const SDNode &);
62 /// SDDbgInfo - Keeps track of dbg_value information through SDISel. We do
63 /// not build SDNodes for these so as not to perturb the generated code;
64 /// instead the info is kept off to the side in this structure. Each SDNode may
65 /// have one or more associated dbg_value entries. This information is kept in
68 SmallVector<SDDbgValue*, 32> DbgValues;
69 DenseMap<const SDNode*, SmallVector<SDDbgValue*, 2> > DbgValMap;
71 void operator=(const SDDbgInfo&); // Do not implement.
72 SDDbgInfo(const SDDbgInfo&); // Do not implement.
76 void add(SDDbgValue *V, const SDNode *Node = 0) {
78 DbgValMap[Node].push_back(V);
79 DbgValues.push_back(V);
88 return DbgValues.empty();
91 SmallVector<SDDbgValue*,2> &getSDDbgValues(const SDNode *Node) {
92 return DbgValMap[Node];
95 typedef SmallVector<SDDbgValue*,32>::iterator DbgIterator;
96 DbgIterator DbgBegin() { return DbgValues.begin(); }
97 DbgIterator DbgEnd() { return DbgValues.end(); }
101 Unrestricted, // Combine may create illegal operations and illegal types.
102 NoIllegalTypes, // Combine may create illegal operations but no illegal types.
103 NoIllegalOperations // Combine may only create legal operations and types.
107 void checkForCycles(const SDNode *N);
108 void checkForCycles(const SelectionDAG *DAG);
110 /// SelectionDAG class - This is used to represent a portion of an LLVM function
111 /// in a low-level Data Dependence DAG representation suitable for instruction
112 /// selection. This DAG is constructed as the first step of instruction
113 /// selection in order to allow implementation of machine specific optimizations
114 /// and code simplifications.
116 /// The representation used by the SelectionDAG is a target-independent
117 /// representation, which has some similarities to the GCC RTL representation,
118 /// but is significantly more simple, powerful, and is a graph form instead of a
124 FunctionLoweringInfo &FLI;
125 MachineModuleInfo *MMI;
127 LLVMContext* Context;
129 /// EntryNode - The starting token.
132 /// Root - The root of the entire DAG.
135 /// AllNodes - A linked list of nodes in the current DAG.
136 ilist<SDNode> AllNodes;
138 /// NodeAllocatorType - The AllocatorType for allocating SDNodes. We use
139 /// pool allocation with recycling.
140 typedef RecyclingAllocator<BumpPtrAllocator, SDNode, sizeof(LargestSDNode),
141 AlignOf<MostAlignedSDNode>::Alignment>
144 /// NodeAllocator - Pool allocation for nodes.
145 NodeAllocatorType NodeAllocator;
147 /// CSEMap - This structure is used to memoize nodes, automatically performing
148 /// CSE with existing nodes when a duplicate is requested.
149 FoldingSet<SDNode> CSEMap;
151 /// OperandAllocator - Pool allocation for machine-opcode SDNode operands.
152 BumpPtrAllocator OperandAllocator;
154 /// Allocator - Pool allocation for misc. objects that are created once per
156 BumpPtrAllocator Allocator;
158 /// SDNodeOrdering - The ordering of the SDNodes. It roughly corresponds to
159 /// the ordering of the original LLVM instructions.
160 SDNodeOrdering *Ordering;
162 /// DbgInfo - Tracks dbg_value information through SDISel.
165 /// VerifyNode - Sanity check the given node. Aborts if it is invalid.
166 void VerifyNode(SDNode *N);
168 /// setGraphColorHelper - Implementation of setSubgraphColor.
169 /// Return whether we had to truncate the search.
171 bool setSubgraphColorHelper(SDNode *N, const char *Color,
172 DenseSet<SDNode *> &visited,
173 int level, bool &printed);
175 void operator=(const SelectionDAG&); // Do not implement.
176 SelectionDAG(const SelectionDAG&); // Do not implement.
179 SelectionDAG(TargetLowering &tli, FunctionLoweringInfo &fli);
182 /// init - Prepare this SelectionDAG to process code in the given
185 void init(MachineFunction &mf, MachineModuleInfo *mmi, DwarfWriter *dw);
187 /// clear - Clear state and free memory necessary to make this
188 /// SelectionDAG ready to process a new block.
192 MachineFunction &getMachineFunction() const { return *MF; }
193 const TargetMachine &getTarget() const;
194 TargetLowering &getTargetLoweringInfo() const { return TLI; }
195 FunctionLoweringInfo &getFunctionLoweringInfo() const { return FLI; }
196 MachineModuleInfo *getMachineModuleInfo() const { return MMI; }
197 DwarfWriter *getDwarfWriter() const { return DW; }
198 LLVMContext *getContext() const {return Context; }
200 /// viewGraph - Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
202 void viewGraph(const std::string &Title);
206 std::map<const SDNode *, std::string> NodeGraphAttrs;
209 /// clearGraphAttrs - Clear all previously defined node graph attributes.
210 /// Intended to be used from a debugging tool (eg. gdb).
211 void clearGraphAttrs();
213 /// setGraphAttrs - Set graph attributes for a node. (eg. "color=red".)
215 void setGraphAttrs(const SDNode *N, const char *Attrs);
217 /// getGraphAttrs - Get graph attributes for a node. (eg. "color=red".)
218 /// Used from getNodeAttributes.
219 const std::string getGraphAttrs(const SDNode *N) const;
221 /// setGraphColor - Convenience for setting node color attribute.
223 void setGraphColor(const SDNode *N, const char *Color);
225 /// setGraphColor - Convenience for setting subgraph color attribute.
227 void setSubgraphColor(SDNode *N, const char *Color);
229 typedef ilist<SDNode>::const_iterator allnodes_const_iterator;
230 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
231 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
232 typedef ilist<SDNode>::iterator allnodes_iterator;
233 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
234 allnodes_iterator allnodes_end() { return AllNodes.end(); }
235 ilist<SDNode>::size_type allnodes_size() const {
236 return AllNodes.size();
239 /// getRoot - Return the root tag of the SelectionDAG.
241 const SDValue &getRoot() const { return Root; }
243 /// getEntryNode - Return the token chain corresponding to the entry of the
245 SDValue getEntryNode() const {
246 return SDValue(const_cast<SDNode *>(&EntryNode), 0);
249 /// setRoot - Set the current root tag of the SelectionDAG.
251 const SDValue &setRoot(SDValue N) {
252 assert((!N.getNode() || N.getValueType() == MVT::Other) &&
253 "DAG root value is not a chain!");
255 checkForCycles(N.getNode());
258 checkForCycles(this);
262 /// Combine - This iterates over the nodes in the SelectionDAG, folding
263 /// certain types of nodes together, or eliminating superfluous nodes. The
264 /// Level argument controls whether Combine is allowed to produce nodes and
265 /// types that are illegal on the target.
266 void Combine(CombineLevel Level, AliasAnalysis &AA,
267 CodeGenOpt::Level OptLevel);
269 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that
270 /// only uses types natively supported by the target. Returns "true" if it
271 /// made any changes.
273 /// Note that this is an involved process that may invalidate pointers into
275 bool LegalizeTypes();
277 /// Legalize - This transforms the SelectionDAG into a SelectionDAG that is
278 /// compatible with the target instruction selector, as indicated by the
279 /// TargetLowering object.
281 /// Note that this is an involved process that may invalidate pointers into
283 void Legalize(CodeGenOpt::Level OptLevel);
285 /// LegalizeVectors - This transforms the SelectionDAG into a SelectionDAG
286 /// that only uses vector math operations supported by the target. This is
287 /// necessary as a separate step from Legalize because unrolling a vector
288 /// operation can introduce illegal types, which requires running
289 /// LegalizeTypes again.
291 /// This returns true if it made any changes; in that case, LegalizeTypes
292 /// is called again before Legalize.
294 /// Note that this is an involved process that may invalidate pointers into
296 bool LegalizeVectors();
298 /// RemoveDeadNodes - This method deletes all unreachable nodes in the
300 void RemoveDeadNodes();
302 /// DeleteNode - Remove the specified node from the system. This node must
303 /// have no referrers.
304 void DeleteNode(SDNode *N);
306 /// getVTList - Return an SDVTList that represents the list of values
308 SDVTList getVTList(EVT VT);
309 SDVTList getVTList(EVT VT1, EVT VT2);
310 SDVTList getVTList(EVT VT1, EVT VT2, EVT VT3);
311 SDVTList getVTList(EVT VT1, EVT VT2, EVT VT3, EVT VT4);
312 SDVTList getVTList(const EVT *VTs, unsigned NumVTs);
314 //===--------------------------------------------------------------------===//
315 // Node creation methods.
317 SDValue getConstant(uint64_t Val, EVT VT, bool isTarget = false);
318 SDValue getConstant(const APInt &Val, EVT VT, bool isTarget = false);
319 SDValue getConstant(const ConstantInt &Val, EVT VT, bool isTarget = false);
320 SDValue getIntPtrConstant(uint64_t Val, bool isTarget = false);
321 SDValue getTargetConstant(uint64_t Val, EVT VT) {
322 return getConstant(Val, VT, true);
324 SDValue getTargetConstant(const APInt &Val, EVT VT) {
325 return getConstant(Val, VT, true);
327 SDValue getTargetConstant(const ConstantInt &Val, EVT VT) {
328 return getConstant(Val, VT, true);
330 SDValue getConstantFP(double Val, EVT VT, bool isTarget = false);
331 SDValue getConstantFP(const APFloat& Val, EVT VT, bool isTarget = false);
332 SDValue getConstantFP(const ConstantFP &CF, EVT VT, bool isTarget = false);
333 SDValue getTargetConstantFP(double Val, EVT VT) {
334 return getConstantFP(Val, VT, true);
336 SDValue getTargetConstantFP(const APFloat& Val, EVT VT) {
337 return getConstantFP(Val, VT, true);
339 SDValue getTargetConstantFP(const ConstantFP &Val, EVT VT) {
340 return getConstantFP(Val, VT, true);
342 SDValue getGlobalAddress(const GlobalValue *GV, EVT VT,
343 int64_t offset = 0, bool isTargetGA = false,
344 unsigned char TargetFlags = 0);
345 SDValue getTargetGlobalAddress(const GlobalValue *GV, EVT VT,
347 unsigned char TargetFlags = 0) {
348 return getGlobalAddress(GV, VT, offset, true, TargetFlags);
350 SDValue getFrameIndex(int FI, EVT VT, bool isTarget = false);
351 SDValue getTargetFrameIndex(int FI, EVT VT) {
352 return getFrameIndex(FI, VT, true);
354 SDValue getJumpTable(int JTI, EVT VT, bool isTarget = false,
355 unsigned char TargetFlags = 0);
356 SDValue getTargetJumpTable(int JTI, EVT VT, unsigned char TargetFlags = 0) {
357 return getJumpTable(JTI, VT, true, TargetFlags);
359 SDValue getConstantPool(Constant *C, EVT VT,
360 unsigned Align = 0, int Offs = 0, bool isT=false,
361 unsigned char TargetFlags = 0);
362 SDValue getTargetConstantPool(Constant *C, EVT VT,
363 unsigned Align = 0, int Offset = 0,
364 unsigned char TargetFlags = 0) {
365 return getConstantPool(C, VT, Align, Offset, true, TargetFlags);
367 SDValue getConstantPool(MachineConstantPoolValue *C, EVT VT,
368 unsigned Align = 0, int Offs = 0, bool isT=false,
369 unsigned char TargetFlags = 0);
370 SDValue getTargetConstantPool(MachineConstantPoolValue *C,
371 EVT VT, unsigned Align = 0,
372 int Offset = 0, unsigned char TargetFlags=0) {
373 return getConstantPool(C, VT, Align, Offset, true, TargetFlags);
375 // When generating a branch to a BB, we don't in general know enough
376 // to provide debug info for the BB at that time, so keep this one around.
377 SDValue getBasicBlock(MachineBasicBlock *MBB);
378 SDValue getBasicBlock(MachineBasicBlock *MBB, DebugLoc dl);
379 SDValue getExternalSymbol(const char *Sym, EVT VT);
380 SDValue getExternalSymbol(const char *Sym, DebugLoc dl, EVT VT);
381 SDValue getTargetExternalSymbol(const char *Sym, EVT VT,
382 unsigned char TargetFlags = 0);
383 SDValue getValueType(EVT);
384 SDValue getRegister(unsigned Reg, EVT VT);
385 SDValue getEHLabel(DebugLoc dl, SDValue Root, MCSymbol *Label);
386 SDValue getBlockAddress(BlockAddress *BA, EVT VT,
387 bool isTarget = false, unsigned char TargetFlags = 0);
389 SDValue getCopyToReg(SDValue Chain, DebugLoc dl, unsigned Reg, SDValue N) {
390 return getNode(ISD::CopyToReg, dl, MVT::Other, Chain,
391 getRegister(Reg, N.getValueType()), N);
394 // This version of the getCopyToReg method takes an extra operand, which
395 // indicates that there is potentially an incoming flag value (if Flag is not
396 // null) and that there should be a flag result.
397 SDValue getCopyToReg(SDValue Chain, DebugLoc dl, unsigned Reg, SDValue N,
399 SDVTList VTs = getVTList(MVT::Other, MVT::Flag);
400 SDValue Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Flag };
401 return getNode(ISD::CopyToReg, dl, VTs, Ops, Flag.getNode() ? 4 : 3);
404 // Similar to last getCopyToReg() except parameter Reg is a SDValue
405 SDValue getCopyToReg(SDValue Chain, DebugLoc dl, SDValue Reg, SDValue N,
407 SDVTList VTs = getVTList(MVT::Other, MVT::Flag);
408 SDValue Ops[] = { Chain, Reg, N, Flag };
409 return getNode(ISD::CopyToReg, dl, VTs, Ops, Flag.getNode() ? 4 : 3);
412 SDValue getCopyFromReg(SDValue Chain, DebugLoc dl, unsigned Reg, EVT VT) {
413 SDVTList VTs = getVTList(VT, MVT::Other);
414 SDValue Ops[] = { Chain, getRegister(Reg, VT) };
415 return getNode(ISD::CopyFromReg, dl, VTs, Ops, 2);
418 // This version of the getCopyFromReg method takes an extra operand, which
419 // indicates that there is potentially an incoming flag value (if Flag is not
420 // null) and that there should be a flag result.
421 SDValue getCopyFromReg(SDValue Chain, DebugLoc dl, unsigned Reg, EVT VT,
423 SDVTList VTs = getVTList(VT, MVT::Other, MVT::Flag);
424 SDValue Ops[] = { Chain, getRegister(Reg, VT), Flag };
425 return getNode(ISD::CopyFromReg, dl, VTs, Ops, Flag.getNode() ? 3 : 2);
428 SDValue getCondCode(ISD::CondCode Cond);
430 /// Returns the ConvertRndSat Note: Avoid using this node because it may
431 /// disappear in the future and most targets don't support it.
432 SDValue getConvertRndSat(EVT VT, DebugLoc dl, SDValue Val, SDValue DTy,
434 SDValue Rnd, SDValue Sat, ISD::CvtCode Code);
436 /// getVectorShuffle - Return an ISD::VECTOR_SHUFFLE node. The number of
437 /// elements in VT, which must be a vector type, must match the number of
438 /// mask elements NumElts. A integer mask element equal to -1 is treated as
440 SDValue getVectorShuffle(EVT VT, DebugLoc dl, SDValue N1, SDValue N2,
441 const int *MaskElts);
443 /// getSExtOrTrunc - Convert Op, which must be of integer type, to the
444 /// integer type VT, by either sign-extending or truncating it.
445 SDValue getSExtOrTrunc(SDValue Op, DebugLoc DL, EVT VT);
447 /// getZExtOrTrunc - Convert Op, which must be of integer type, to the
448 /// integer type VT, by either zero-extending or truncating it.
449 SDValue getZExtOrTrunc(SDValue Op, DebugLoc DL, EVT VT);
451 /// getZeroExtendInReg - Return the expression required to zero extend the Op
452 /// value assuming it was the smaller SrcTy value.
453 SDValue getZeroExtendInReg(SDValue Op, DebugLoc DL, EVT SrcTy);
455 /// getNOT - Create a bitwise NOT operation as (XOR Val, -1).
456 SDValue getNOT(DebugLoc DL, SDValue Val, EVT VT);
458 /// getCALLSEQ_START - Return a new CALLSEQ_START node, which always must have
459 /// a flag result (to ensure it's not CSE'd). CALLSEQ_START does not have a
461 SDValue getCALLSEQ_START(SDValue Chain, SDValue Op) {
462 SDVTList VTs = getVTList(MVT::Other, MVT::Flag);
463 SDValue Ops[] = { Chain, Op };
464 return getNode(ISD::CALLSEQ_START, DebugLoc::getUnknownLoc(),
468 /// getCALLSEQ_END - Return a new CALLSEQ_END node, which always must have a
469 /// flag result (to ensure it's not CSE'd). CALLSEQ_END does not have
470 /// a useful DebugLoc.
471 SDValue getCALLSEQ_END(SDValue Chain, SDValue Op1, SDValue Op2,
473 SDVTList NodeTys = getVTList(MVT::Other, MVT::Flag);
474 SmallVector<SDValue, 4> Ops;
475 Ops.push_back(Chain);
478 Ops.push_back(InFlag);
479 return getNode(ISD::CALLSEQ_END, DebugLoc::getUnknownLoc(), NodeTys,
481 (unsigned)Ops.size() - (InFlag.getNode() == 0 ? 1 : 0));
484 /// getUNDEF - Return an UNDEF node. UNDEF does not have a useful DebugLoc.
485 SDValue getUNDEF(EVT VT) {
486 return getNode(ISD::UNDEF, DebugLoc::getUnknownLoc(), VT);
489 /// getGLOBAL_OFFSET_TABLE - Return a GLOBAL_OFFSET_TABLE node. This does
490 /// not have a useful DebugLoc.
491 SDValue getGLOBAL_OFFSET_TABLE(EVT VT) {
492 return getNode(ISD::GLOBAL_OFFSET_TABLE, DebugLoc::getUnknownLoc(), VT);
495 /// getNode - Gets or creates the specified node.
497 SDValue getNode(unsigned Opcode, DebugLoc DL, EVT VT);
498 SDValue getNode(unsigned Opcode, DebugLoc DL, EVT VT, SDValue N);
499 SDValue getNode(unsigned Opcode, DebugLoc DL, EVT VT, SDValue N1, SDValue N2);
500 SDValue getNode(unsigned Opcode, DebugLoc DL, EVT VT,
501 SDValue N1, SDValue N2, SDValue N3);
502 SDValue getNode(unsigned Opcode, DebugLoc DL, EVT VT,
503 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
504 SDValue getNode(unsigned Opcode, DebugLoc DL, EVT VT,
505 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
507 SDValue getNode(unsigned Opcode, DebugLoc DL, EVT VT,
508 const SDUse *Ops, unsigned NumOps);
509 SDValue getNode(unsigned Opcode, DebugLoc DL, EVT VT,
510 const SDValue *Ops, unsigned NumOps);
511 SDValue getNode(unsigned Opcode, DebugLoc DL,
512 const std::vector<EVT> &ResultTys,
513 const SDValue *Ops, unsigned NumOps);
514 SDValue getNode(unsigned Opcode, DebugLoc DL, const EVT *VTs, unsigned NumVTs,
515 const SDValue *Ops, unsigned NumOps);
516 SDValue getNode(unsigned Opcode, DebugLoc DL, SDVTList VTs,
517 const SDValue *Ops, unsigned NumOps);
518 SDValue getNode(unsigned Opcode, DebugLoc DL, SDVTList VTs);
519 SDValue getNode(unsigned Opcode, DebugLoc DL, SDVTList VTs, SDValue N);
520 SDValue getNode(unsigned Opcode, DebugLoc DL, SDVTList VTs,
521 SDValue N1, SDValue N2);
522 SDValue getNode(unsigned Opcode, DebugLoc DL, SDVTList VTs,
523 SDValue N1, SDValue N2, SDValue N3);
524 SDValue getNode(unsigned Opcode, DebugLoc DL, SDVTList VTs,
525 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
526 SDValue getNode(unsigned Opcode, DebugLoc DL, SDVTList VTs,
527 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
530 /// getStackArgumentTokenFactor - Compute a TokenFactor to force all
531 /// the incoming stack arguments to be loaded from the stack. This is
532 /// used in tail call lowering to protect stack arguments from being
534 SDValue getStackArgumentTokenFactor(SDValue Chain);
536 SDValue getMemcpy(SDValue Chain, DebugLoc dl, SDValue Dst, SDValue Src,
537 SDValue Size, unsigned Align, bool isVol, bool AlwaysInline,
538 const Value *DstSV, uint64_t DstSVOff,
539 const Value *SrcSV, uint64_t SrcSVOff);
541 SDValue getMemmove(SDValue Chain, DebugLoc dl, SDValue Dst, SDValue Src,
542 SDValue Size, unsigned Align, bool isVol,
543 const Value *DstSV, uint64_t DstOSVff,
544 const Value *SrcSV, uint64_t SrcSVOff);
546 SDValue getMemset(SDValue Chain, DebugLoc dl, SDValue Dst, SDValue Src,
547 SDValue Size, unsigned Align, bool isVol,
548 const Value *DstSV, uint64_t DstSVOff);
550 /// getSetCC - Helper function to make it easier to build SetCC's if you just
551 /// have an ISD::CondCode instead of an SDValue.
553 SDValue getSetCC(DebugLoc DL, EVT VT, SDValue LHS, SDValue RHS,
554 ISD::CondCode Cond) {
555 return getNode(ISD::SETCC, DL, VT, LHS, RHS, getCondCode(Cond));
558 /// getVSetCC - Helper function to make it easier to build VSetCC's nodes
559 /// if you just have an ISD::CondCode instead of an SDValue.
561 SDValue getVSetCC(DebugLoc DL, EVT VT, SDValue LHS, SDValue RHS,
562 ISD::CondCode Cond) {
563 return getNode(ISD::VSETCC, DL, VT, LHS, RHS, getCondCode(Cond));
566 /// getSelectCC - Helper function to make it easier to build SelectCC's if you
567 /// just have an ISD::CondCode instead of an SDValue.
569 SDValue getSelectCC(DebugLoc DL, SDValue LHS, SDValue RHS,
570 SDValue True, SDValue False, ISD::CondCode Cond) {
571 return getNode(ISD::SELECT_CC, DL, True.getValueType(),
572 LHS, RHS, True, False, getCondCode(Cond));
575 /// getVAArg - VAArg produces a result and token chain, and takes a pointer
576 /// and a source value as input.
577 SDValue getVAArg(EVT VT, DebugLoc dl, SDValue Chain, SDValue Ptr,
580 /// getAtomic - Gets a node for an atomic op, produces result and chain and
582 SDValue getAtomic(unsigned Opcode, DebugLoc dl, EVT MemVT, SDValue Chain,
583 SDValue Ptr, SDValue Cmp, SDValue Swp, const Value* PtrVal,
584 unsigned Alignment=0);
585 SDValue getAtomic(unsigned Opcode, DebugLoc dl, EVT MemVT, SDValue Chain,
586 SDValue Ptr, SDValue Cmp, SDValue Swp,
587 MachineMemOperand *MMO);
589 /// getAtomic - Gets a node for an atomic op, produces result and chain and
590 /// takes 2 operands.
591 SDValue getAtomic(unsigned Opcode, DebugLoc dl, EVT MemVT, SDValue Chain,
592 SDValue Ptr, SDValue Val, const Value* PtrVal,
593 unsigned Alignment = 0);
594 SDValue getAtomic(unsigned Opcode, DebugLoc dl, EVT MemVT, SDValue Chain,
595 SDValue Ptr, SDValue Val,
596 MachineMemOperand *MMO);
598 /// getMemIntrinsicNode - Creates a MemIntrinsicNode that may produce a
599 /// result and takes a list of operands. Opcode may be INTRINSIC_VOID,
600 /// INTRINSIC_W_CHAIN, or a target-specific opcode with a value not
601 /// less than FIRST_TARGET_MEMORY_OPCODE.
602 SDValue getMemIntrinsicNode(unsigned Opcode, DebugLoc dl,
603 const EVT *VTs, unsigned NumVTs,
604 const SDValue *Ops, unsigned NumOps,
605 EVT MemVT, const Value *srcValue, int SVOff,
606 unsigned Align = 0, bool Vol = false,
607 bool ReadMem = true, bool WriteMem = true);
609 SDValue getMemIntrinsicNode(unsigned Opcode, DebugLoc dl, SDVTList VTList,
610 const SDValue *Ops, unsigned NumOps,
611 EVT MemVT, const Value *srcValue, int SVOff,
612 unsigned Align = 0, bool Vol = false,
613 bool ReadMem = true, bool WriteMem = true);
615 SDValue getMemIntrinsicNode(unsigned Opcode, DebugLoc dl, SDVTList VTList,
616 const SDValue *Ops, unsigned NumOps,
617 EVT MemVT, MachineMemOperand *MMO);
619 /// getMergeValues - Create a MERGE_VALUES node from the given operands.
620 SDValue getMergeValues(const SDValue *Ops, unsigned NumOps, DebugLoc dl);
622 /// getLoad - Loads are not normal binary operators: their result type is not
623 /// determined by their operands, and they produce a value AND a token chain.
625 SDValue getLoad(EVT VT, DebugLoc dl, SDValue Chain, SDValue Ptr,
626 const Value *SV, int SVOffset, bool isVolatile,
627 bool isNonTemporal, unsigned Alignment);
628 SDValue getExtLoad(ISD::LoadExtType ExtType, DebugLoc dl, EVT VT,
629 SDValue Chain, SDValue Ptr, const Value *SV,
630 int SVOffset, EVT MemVT, bool isVolatile,
631 bool isNonTemporal, unsigned Alignment);
632 SDValue getIndexedLoad(SDValue OrigLoad, DebugLoc dl, SDValue Base,
633 SDValue Offset, ISD::MemIndexedMode AM);
634 SDValue getLoad(ISD::MemIndexedMode AM, DebugLoc dl, ISD::LoadExtType ExtType,
635 EVT VT, SDValue Chain, SDValue Ptr, SDValue Offset,
636 const Value *SV, int SVOffset, EVT MemVT,
637 bool isVolatile, bool isNonTemporal, unsigned Alignment);
638 SDValue getLoad(ISD::MemIndexedMode AM, DebugLoc dl, ISD::LoadExtType ExtType,
639 EVT VT, SDValue Chain, SDValue Ptr, SDValue Offset,
640 EVT MemVT, MachineMemOperand *MMO);
642 /// getStore - Helper function to build ISD::STORE nodes.
644 SDValue getStore(SDValue Chain, DebugLoc dl, SDValue Val, SDValue Ptr,
645 const Value *SV, int SVOffset, bool isVolatile,
646 bool isNonTemporal, unsigned Alignment);
647 SDValue getStore(SDValue Chain, DebugLoc dl, SDValue Val, SDValue Ptr,
648 MachineMemOperand *MMO);
649 SDValue getTruncStore(SDValue Chain, DebugLoc dl, SDValue Val, SDValue Ptr,
650 const Value *SV, int SVOffset, EVT TVT,
651 bool isNonTemporal, bool isVolatile,
653 SDValue getTruncStore(SDValue Chain, DebugLoc dl, SDValue Val, SDValue Ptr,
654 EVT TVT, MachineMemOperand *MMO);
655 SDValue getIndexedStore(SDValue OrigStoe, DebugLoc dl, SDValue Base,
656 SDValue Offset, ISD::MemIndexedMode AM);
658 /// getSrcValue - Construct a node to track a Value* through the backend.
659 SDValue getSrcValue(const Value *v);
661 /// getShiftAmountOperand - Return the specified value casted to
662 /// the target's desired shift amount type.
663 SDValue getShiftAmountOperand(SDValue Op);
665 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the
666 /// specified operands. If the resultant node already exists in the DAG,
667 /// this does not modify the specified node, instead it returns the node that
668 /// already exists. If the resultant node does not exist in the DAG, the
669 /// input node is returned. As a degenerate case, if you specify the same
670 /// input operands as the node already has, the input node is returned.
671 SDValue UpdateNodeOperands(SDValue N, SDValue Op);
672 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2);
673 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
675 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
676 SDValue Op3, SDValue Op4);
677 SDValue UpdateNodeOperands(SDValue N, SDValue Op1, SDValue Op2,
678 SDValue Op3, SDValue Op4, SDValue Op5);
679 SDValue UpdateNodeOperands(SDValue N,
680 const SDValue *Ops, unsigned NumOps);
682 /// SelectNodeTo - These are used for target selectors to *mutate* the
683 /// specified node to have the specified return type, Target opcode, and
684 /// operands. Note that target opcodes are stored as
685 /// ~TargetOpcode in the node opcode field. The resultant node is returned.
686 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT);
687 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT, SDValue Op1);
688 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
689 SDValue Op1, SDValue Op2);
690 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
691 SDValue Op1, SDValue Op2, SDValue Op3);
692 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
693 const SDValue *Ops, unsigned NumOps);
694 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1, EVT VT2);
695 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
696 EVT VT2, const SDValue *Ops, unsigned NumOps);
697 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
698 EVT VT2, EVT VT3, const SDValue *Ops, unsigned NumOps);
699 SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT1,
700 EVT VT2, EVT VT3, EVT VT4, const SDValue *Ops,
702 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
703 EVT VT2, SDValue Op1);
704 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
705 EVT VT2, SDValue Op1, SDValue Op2);
706 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
707 EVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
708 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
709 EVT VT2, EVT VT3, SDValue Op1, SDValue Op2, SDValue Op3);
710 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
711 const SDValue *Ops, unsigned NumOps);
713 /// MorphNodeTo - This *mutates* the specified node to have the specified
714 /// return type, opcode, and operands.
715 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
716 const SDValue *Ops, unsigned NumOps);
718 /// getMachineNode - These are used for target selectors to create a new node
719 /// with specified return type(s), MachineInstr opcode, and operands.
721 /// Note that getMachineNode returns the resultant node. If there is already
722 /// a node of the specified opcode and operands, it returns that node instead
723 /// of the current one.
724 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, EVT VT);
725 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, EVT VT,
727 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, EVT VT,
728 SDValue Op1, SDValue Op2);
729 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, EVT VT,
730 SDValue Op1, SDValue Op2, SDValue Op3);
731 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, EVT VT,
732 const SDValue *Ops, unsigned NumOps);
733 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, EVT VT1, EVT VT2);
734 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, EVT VT1, EVT VT2,
736 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, EVT VT1,
737 EVT VT2, SDValue Op1, SDValue Op2);
738 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, EVT VT1,
739 EVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
740 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, EVT VT1, EVT VT2,
741 const SDValue *Ops, unsigned NumOps);
742 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, EVT VT1, EVT VT2,
743 EVT VT3, SDValue Op1, SDValue Op2);
744 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, EVT VT1, EVT VT2,
745 EVT VT3, SDValue Op1, SDValue Op2, SDValue Op3);
746 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, EVT VT1, EVT VT2,
747 EVT VT3, const SDValue *Ops, unsigned NumOps);
748 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, EVT VT1, EVT VT2,
749 EVT VT3, EVT VT4, const SDValue *Ops, unsigned NumOps);
750 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl,
751 const std::vector<EVT> &ResultTys, const SDValue *Ops,
753 MachineSDNode *getMachineNode(unsigned Opcode, DebugLoc dl, SDVTList VTs,
754 const SDValue *Ops, unsigned NumOps);
756 /// getTargetExtractSubreg - A convenience function for creating
757 /// TargetInstrInfo::EXTRACT_SUBREG nodes.
758 SDValue getTargetExtractSubreg(int SRIdx, DebugLoc DL, EVT VT,
761 /// getTargetInsertSubreg - A convenience function for creating
762 /// TargetInstrInfo::INSERT_SUBREG nodes.
763 SDValue getTargetInsertSubreg(int SRIdx, DebugLoc DL, EVT VT,
764 SDValue Operand, SDValue Subreg);
766 /// getNodeIfExists - Get the specified node if it's already available, or
767 /// else return NULL.
768 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs,
769 const SDValue *Ops, unsigned NumOps);
771 /// getDbgValue - Creates a SDDbgValue node.
773 SDDbgValue *getDbgValue(MDNode *MDPtr, SDNode *N, unsigned R, uint64_t Off,
774 DebugLoc DL, unsigned O);
775 SDDbgValue *getDbgValue(MDNode *MDPtr, Value *C, uint64_t Off,
776 DebugLoc DL, unsigned O);
777 SDDbgValue *getDbgValue(MDNode *MDPtr, unsigned FI, uint64_t Off,
778 DebugLoc DL, unsigned O);
780 /// DAGUpdateListener - Clients of various APIs that cause global effects on
781 /// the DAG can optionally implement this interface. This allows the clients
782 /// to handle the various sorts of updates that happen.
783 class DAGUpdateListener {
785 virtual ~DAGUpdateListener();
787 /// NodeDeleted - The node N that was deleted and, if E is not null, an
788 /// equivalent node E that replaced it.
789 virtual void NodeDeleted(SDNode *N, SDNode *E) = 0;
791 /// NodeUpdated - The node N that was updated.
792 virtual void NodeUpdated(SDNode *N) = 0;
795 /// RemoveDeadNode - Remove the specified node from the system. If any of its
796 /// operands then becomes dead, remove them as well. Inform UpdateListener
797 /// for each node deleted.
798 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0);
800 /// RemoveDeadNodes - This method deletes the unreachable nodes in the
801 /// given list, and any nodes that become unreachable as a result.
802 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes,
803 DAGUpdateListener *UpdateListener = 0);
805 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
806 /// This can cause recursive merging of nodes in the DAG. Use the first
807 /// version if 'From' is known to have a single result, use the second
808 /// if you have two nodes with identical results (or if 'To' has a superset
809 /// of the results of 'From'), use the third otherwise.
811 /// These methods all take an optional UpdateListener, which (if not null) is
812 /// informed about nodes that are deleted and modified due to recursive
813 /// changes in the dag.
815 /// These functions only replace all existing uses. It's possible that as
816 /// these replacements are being performed, CSE may cause the From node
817 /// to be given new uses. These new uses of From are left in place, and
818 /// not automatically transfered to To.
820 void ReplaceAllUsesWith(SDValue From, SDValue Op,
821 DAGUpdateListener *UpdateListener = 0);
822 void ReplaceAllUsesWith(SDNode *From, SDNode *To,
823 DAGUpdateListener *UpdateListener = 0);
824 void ReplaceAllUsesWith(SDNode *From, const SDValue *To,
825 DAGUpdateListener *UpdateListener = 0);
827 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving
828 /// uses of other values produced by From.Val alone.
829 void ReplaceAllUsesOfValueWith(SDValue From, SDValue To,
830 DAGUpdateListener *UpdateListener = 0);
832 /// ReplaceAllUsesOfValuesWith - Like ReplaceAllUsesOfValueWith, but
833 /// for multiple values at once. This correctly handles the case where
834 /// there is an overlap between the From values and the To values.
835 void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To,
837 DAGUpdateListener *UpdateListener = 0);
839 /// AssignTopologicalOrder - Topological-sort the AllNodes list and a
840 /// assign a unique node id for each node in the DAG based on their
841 /// topological order. Returns the number of nodes.
842 unsigned AssignTopologicalOrder();
844 /// RepositionNode - Move node N in the AllNodes list to be immediately
845 /// before the given iterator Position. This may be used to update the
846 /// topological ordering when the list of nodes is modified.
847 void RepositionNode(allnodes_iterator Position, SDNode *N) {
848 AllNodes.insert(Position, AllNodes.remove(N));
851 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary
853 static bool isCommutativeBinOp(unsigned Opcode) {
854 // FIXME: This should get its info from the td file, so that we can include
871 case ISD::ADDE: return true;
872 default: return false;
876 /// AssignOrdering - Assign an order to the SDNode.
877 void AssignOrdering(const SDNode *SD, unsigned Order);
879 /// GetOrdering - Get the order for the SDNode.
880 unsigned GetOrdering(const SDNode *SD) const;
882 /// AddDbgValue - Add a dbg_value SDNode. If SD is non-null that means the
883 /// value is produced by SD.
884 void AddDbgValue(SDDbgValue *DB, SDNode *SD = 0);
886 /// GetDbgValues - Get the debug values which reference the given SDNode.
887 SmallVector<SDDbgValue*,2> &GetDbgValues(const SDNode* SD) {
888 return DbgInfo->getSDDbgValues(SD);
891 /// hasDebugValues - Return true if there are any SDDbgValue nodes associated
892 /// with this SelectionDAG.
893 bool hasDebugValues() const { return !DbgInfo->empty(); }
895 SDDbgInfo::DbgIterator DbgBegin() { return DbgInfo->DbgBegin(); }
896 SDDbgInfo::DbgIterator DbgEnd() { return DbgInfo->DbgEnd(); }
900 /// CreateStackTemporary - Create a stack temporary, suitable for holding the
901 /// specified value type. If minAlign is specified, the slot size will have
902 /// at least that alignment.
903 SDValue CreateStackTemporary(EVT VT, unsigned minAlign = 1);
905 /// CreateStackTemporary - Create a stack temporary suitable for holding
906 /// either of the specified value types.
907 SDValue CreateStackTemporary(EVT VT1, EVT VT2);
909 /// FoldConstantArithmetic -
910 SDValue FoldConstantArithmetic(unsigned Opcode,
912 ConstantSDNode *Cst1,
913 ConstantSDNode *Cst2);
915 /// FoldSetCC - Constant fold a setcc to true or false.
916 SDValue FoldSetCC(EVT VT, SDValue N1,
917 SDValue N2, ISD::CondCode Cond, DebugLoc dl);
919 /// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We
920 /// use this predicate to simplify operations downstream.
921 bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const;
923 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We
924 /// use this predicate to simplify operations downstream. Op and Mask are
925 /// known to be the same type.
926 bool MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth = 0)
929 /// ComputeMaskedBits - Determine which of the bits specified in Mask are
930 /// known to be either zero or one and return them in the KnownZero/KnownOne
931 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit
932 /// processing. Targets can implement the computeMaskedBitsForTargetNode
933 /// method in the TargetLowering class to allow target nodes to be understood.
934 void ComputeMaskedBits(SDValue Op, const APInt &Mask, APInt &KnownZero,
935 APInt &KnownOne, unsigned Depth = 0) const;
937 /// ComputeNumSignBits - Return the number of times the sign bit of the
938 /// register is replicated into the other bits. We know that at least 1 bit
939 /// is always equal to the sign bit (itself), but other cases can give us
940 /// information. For example, immediately after an "SRA X, 2", we know that
941 /// the top 3 bits are all equal to each other, so we return 3. Targets can
942 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
943 /// class to allow target nodes to be understood.
944 unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const;
946 /// isKnownNeverNan - Test whether the given SDValue is known to never be NaN.
947 bool isKnownNeverNaN(SDValue Op) const;
949 /// isKnownNeverZero - Test whether the given SDValue is known to never be
950 /// positive or negative Zero.
951 bool isKnownNeverZero(SDValue Op) const;
953 /// isEqualTo - Test whether two SDValues are known to compare equal. This
954 /// is true if they are the same value, or if one is negative zero and the
955 /// other positive zero.
956 bool isEqualTo(SDValue A, SDValue B) const;
958 /// isVerifiedDebugInfoDesc - Returns true if the specified SDValue has
959 /// been verified as a debug information descriptor.
960 bool isVerifiedDebugInfoDesc(SDValue Op) const;
962 /// getShuffleScalarElt - Returns the scalar element that will make up the ith
963 /// element of the result of the vector shuffle.
964 SDValue getShuffleScalarElt(const ShuffleVectorSDNode *N, unsigned Idx);
966 /// UnrollVectorOp - Utility function used by legalize and lowering to
967 /// "unroll" a vector operation by splitting out the scalars and operating
968 /// on each element individually. If the ResNE is 0, fully unroll the vector
969 /// op. If ResNE is less than the width of the vector op, unroll up to ResNE.
970 /// If the ResNE is greater than the width of the vector op, unroll the
971 /// vector op and fill the end of the resulting vector with UNDEFS.
972 SDValue UnrollVectorOp(SDNode *N, unsigned ResNE = 0);
974 /// isConsecutiveLoad - Return true if LD is loading 'Bytes' bytes from a
975 /// location that is 'Dist' units away from the location that the 'Base' load
977 bool isConsecutiveLoad(LoadSDNode *LD, LoadSDNode *Base,
978 unsigned Bytes, int Dist) const;
980 /// InferPtrAlignment - Infer alignment of a load / store address. Return 0 if
981 /// it cannot be inferred.
982 unsigned InferPtrAlignment(SDValue Ptr) const;
985 bool RemoveNodeFromCSEMaps(SDNode *N);
986 void AddModifiedNodeToCSEMaps(SDNode *N, DAGUpdateListener *UpdateListener);
987 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos);
988 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2,
990 SDNode *FindModifiedNodeSlot(SDNode *N, const SDValue *Ops, unsigned NumOps,
993 void DeleteNodeNotInCSEMaps(SDNode *N);
994 void DeallocateNode(SDNode *N);
996 unsigned getEVTAlignment(EVT MemoryVT) const;
998 void allnodes_clear();
1000 /// VTList - List of non-single value types.
1001 std::vector<SDVTList> VTList;
1003 /// CondCodeNodes - Maps to auto-CSE operations.
1004 std::vector<CondCodeSDNode*> CondCodeNodes;
1006 std::vector<SDNode*> ValueTypeNodes;
1007 std::map<EVT, SDNode*, EVT::compareRawBits> ExtendedValueTypeNodes;
1008 StringMap<SDNode*> ExternalSymbols;
1010 std::map<std::pair<std::string, unsigned char>,SDNode*> TargetExternalSymbols;
1013 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
1014 typedef SelectionDAG::allnodes_iterator nodes_iterator;
1015 static nodes_iterator nodes_begin(SelectionDAG *G) {
1016 return G->allnodes_begin();
1018 static nodes_iterator nodes_end(SelectionDAG *G) {
1019 return G->allnodes_end();
1023 } // end namespace llvm