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/DenseSet.h"
19 #include "llvm/ADT/SetVector.h"
20 #include "llvm/ADT/StringMap.h"
21 #include "llvm/ADT/ilist.h"
22 #include "llvm/CodeGen/DAGCombine.h"
23 #include "llvm/CodeGen/MachineFunction.h"
24 #include "llvm/CodeGen/SelectionDAGNodes.h"
25 #include "llvm/Support/RecyclingAllocator.h"
26 #include "llvm/Target/TargetMachine.h"
35 class MachineConstantPoolValue;
36 class MachineFunction;
40 class TargetSelectionDAGInfo;
42 class SDVTListNode : public FoldingSetNode {
43 friend struct FoldingSetTrait<SDVTListNode>;
44 /// A reference to an Interned FoldingSetNodeID for this node.
45 /// The Allocator in SelectionDAG holds the data.
46 /// SDVTList contains all types which are frequently accessed in SelectionDAG.
47 /// The size of this list is not expected to be big so it won't introduce
49 FoldingSetNodeIDRef FastID;
52 /// The hash value for SDVTList is fixed, so cache it to avoid
56 SDVTListNode(const FoldingSetNodeIDRef ID, const EVT *VT, unsigned int Num) :
57 FastID(ID), VTs(VT), NumVTs(Num) {
58 HashValue = ID.ComputeHash();
60 SDVTList getSDVTList() {
61 SDVTList result = {VTs, NumVTs};
66 /// Specialize FoldingSetTrait for SDVTListNode
67 /// to avoid computing temp FoldingSetNodeID and hash value.
68 template<> struct FoldingSetTrait<SDVTListNode> : DefaultFoldingSetTrait<SDVTListNode> {
69 static void Profile(const SDVTListNode &X, FoldingSetNodeID& ID) {
72 static bool Equals(const SDVTListNode &X, const FoldingSetNodeID &ID,
73 unsigned IDHash, FoldingSetNodeID &TempID) {
74 if (X.HashValue != IDHash)
76 return ID == X.FastID;
78 static unsigned ComputeHash(const SDVTListNode &X, FoldingSetNodeID &TempID) {
83 template<> struct ilist_traits<SDNode> : public ilist_default_traits<SDNode> {
85 mutable ilist_half_node<SDNode> Sentinel;
87 SDNode *createSentinel() const {
88 return static_cast<SDNode*>(&Sentinel);
90 static void destroySentinel(SDNode *) {}
92 SDNode *provideInitialHead() const { return createSentinel(); }
93 SDNode *ensureHead(SDNode*) const { return createSentinel(); }
94 static void noteHead(SDNode*, SDNode*) {}
96 static void deleteNode(SDNode *) {
97 llvm_unreachable("ilist_traits<SDNode> shouldn't see a deleteNode call!");
100 static void createNode(const SDNode &);
103 /// Keeps track of dbg_value information through SDISel. We do
104 /// not build SDNodes for these so as not to perturb the generated code;
105 /// instead the info is kept off to the side in this structure. Each SDNode may
106 /// have one or more associated dbg_value entries. This information is kept in
108 /// Byval parameters are handled separately because they don't use alloca's,
109 /// which busts the normal mechanism. There is good reason for handling all
110 /// parameters separately: they may not have code generated for them, they
111 /// should always go at the beginning of the function regardless of other code
112 /// motion, and debug info for them is potentially useful even if the parameter
113 /// is unused. Right now only byval parameters are handled separately.
115 BumpPtrAllocator Alloc;
116 SmallVector<SDDbgValue*, 32> DbgValues;
117 SmallVector<SDDbgValue*, 32> ByvalParmDbgValues;
118 typedef DenseMap<const SDNode*, SmallVector<SDDbgValue*, 2> > DbgValMapType;
119 DbgValMapType DbgValMap;
121 void operator=(const SDDbgInfo&) = delete;
122 SDDbgInfo(const SDDbgInfo&) = delete;
126 void add(SDDbgValue *V, const SDNode *Node, bool isParameter) {
128 ByvalParmDbgValues.push_back(V);
129 } else DbgValues.push_back(V);
131 DbgValMap[Node].push_back(V);
134 /// \brief Invalidate all DbgValues attached to the node and remove
135 /// it from the Node-to-DbgValues map.
136 void erase(const SDNode *Node);
141 ByvalParmDbgValues.clear();
145 BumpPtrAllocator &getAlloc() { return Alloc; }
148 return DbgValues.empty() && ByvalParmDbgValues.empty();
151 ArrayRef<SDDbgValue*> getSDDbgValues(const SDNode *Node) {
152 DbgValMapType::iterator I = DbgValMap.find(Node);
153 if (I != DbgValMap.end())
155 return ArrayRef<SDDbgValue*>();
158 typedef SmallVectorImpl<SDDbgValue*>::iterator DbgIterator;
159 DbgIterator DbgBegin() { return DbgValues.begin(); }
160 DbgIterator DbgEnd() { return DbgValues.end(); }
161 DbgIterator ByvalParmDbgBegin() { return ByvalParmDbgValues.begin(); }
162 DbgIterator ByvalParmDbgEnd() { return ByvalParmDbgValues.end(); }
166 void checkForCycles(const SelectionDAG *DAG, bool force = false);
168 /// This is used to represent a portion of an LLVM function in a low-level
169 /// Data Dependence DAG representation suitable for instruction selection.
170 /// This DAG is constructed as the first step of instruction selection in order
171 /// to allow implementation of machine specific optimizations
172 /// and code simplifications.
174 /// The representation used by the SelectionDAG is a target-independent
175 /// representation, which has some similarities to the GCC RTL representation,
176 /// but is significantly more simple, powerful, and is a graph form instead of a
180 const TargetMachine &TM;
181 const TargetSelectionDAGInfo *TSI;
182 const TargetLowering *TLI;
184 LLVMContext *Context;
185 CodeGenOpt::Level OptLevel;
187 /// The starting token.
190 /// The root of the entire DAG.
193 /// A linked list of nodes in the current DAG.
194 ilist<SDNode> AllNodes;
196 /// The AllocatorType for allocating SDNodes. We use
197 /// pool allocation with recycling.
198 typedef RecyclingAllocator<BumpPtrAllocator, SDNode, sizeof(LargestSDNode),
199 AlignOf<MostAlignedSDNode>::Alignment>
202 /// Pool allocation for nodes.
203 NodeAllocatorType NodeAllocator;
205 /// This structure is used to memoize nodes, automatically performing
206 /// CSE with existing nodes when a duplicate is requested.
207 FoldingSet<SDNode> CSEMap;
209 /// Pool allocation for machine-opcode SDNode operands.
210 BumpPtrAllocator OperandAllocator;
212 /// Pool allocation for misc. objects that are created once per SelectionDAG.
213 BumpPtrAllocator Allocator;
215 /// Tracks dbg_value information through SDISel.
219 /// Clients of various APIs that cause global effects on
220 /// the DAG can optionally implement this interface. This allows the clients
221 /// to handle the various sorts of updates that happen.
223 /// A DAGUpdateListener automatically registers itself with DAG when it is
224 /// constructed, and removes itself when destroyed in RAII fashion.
225 struct DAGUpdateListener {
226 DAGUpdateListener *const Next;
229 explicit DAGUpdateListener(SelectionDAG &D)
230 : Next(D.UpdateListeners), DAG(D) {
231 DAG.UpdateListeners = this;
234 virtual ~DAGUpdateListener() {
235 assert(DAG.UpdateListeners == this &&
236 "DAGUpdateListeners must be destroyed in LIFO order");
237 DAG.UpdateListeners = Next;
240 /// The node N that was deleted and, if E is not null, an
241 /// equivalent node E that replaced it.
242 virtual void NodeDeleted(SDNode *N, SDNode *E);
244 /// The node N that was updated.
245 virtual void NodeUpdated(SDNode *N);
248 /// When true, additional steps are taken to
249 /// ensure that getConstant() and similar functions return DAG nodes that
250 /// have legal types. This is important after type legalization since
251 /// any illegally typed nodes generated after this point will not experience
252 /// type legalization.
253 bool NewNodesMustHaveLegalTypes;
256 /// DAGUpdateListener is a friend so it can manipulate the listener stack.
257 friend struct DAGUpdateListener;
259 /// Linked list of registered DAGUpdateListener instances.
260 /// This stack is maintained by DAGUpdateListener RAII.
261 DAGUpdateListener *UpdateListeners;
263 /// Implementation of setSubgraphColor.
264 /// Return whether we had to truncate the search.
265 bool setSubgraphColorHelper(SDNode *N, const char *Color,
266 DenseSet<SDNode *> &visited,
267 int level, bool &printed);
269 void operator=(const SelectionDAG&) = delete;
270 SelectionDAG(const SelectionDAG&) = delete;
273 explicit SelectionDAG(const TargetMachine &TM, llvm::CodeGenOpt::Level);
276 /// Prepare this SelectionDAG to process code in the given MachineFunction.
277 void init(MachineFunction &mf);
279 /// Clear state and free memory necessary to make this
280 /// SelectionDAG ready to process a new block.
283 MachineFunction &getMachineFunction() const { return *MF; }
284 const TargetMachine &getTarget() const { return TM; }
285 const TargetSubtargetInfo &getSubtarget() const { return MF->getSubtarget(); }
286 const TargetLowering &getTargetLoweringInfo() const { return *TLI; }
287 const TargetSelectionDAGInfo &getSelectionDAGInfo() const { return *TSI; }
288 LLVMContext *getContext() const {return Context; }
290 /// Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
291 void viewGraph(const std::string &Title);
295 std::map<const SDNode *, std::string> NodeGraphAttrs;
298 /// Clear all previously defined node graph attributes.
299 /// Intended to be used from a debugging tool (eg. gdb).
300 void clearGraphAttrs();
302 /// Set graph attributes for a node. (eg. "color=red".)
303 void setGraphAttrs(const SDNode *N, const char *Attrs);
305 /// Get graph attributes for a node. (eg. "color=red".)
306 /// Used from getNodeAttributes.
307 const std::string getGraphAttrs(const SDNode *N) const;
309 /// Convenience for setting node color attribute.
310 void setGraphColor(const SDNode *N, const char *Color);
312 /// Convenience for setting subgraph color attribute.
313 void setSubgraphColor(SDNode *N, const char *Color);
315 typedef ilist<SDNode>::const_iterator allnodes_const_iterator;
316 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
317 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
318 typedef ilist<SDNode>::iterator allnodes_iterator;
319 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
320 allnodes_iterator allnodes_end() { return AllNodes.end(); }
321 ilist<SDNode>::size_type allnodes_size() const {
322 return AllNodes.size();
325 /// Return the root tag of the SelectionDAG.
326 const SDValue &getRoot() const { return Root; }
328 /// Return the token chain corresponding to the entry of the function.
329 SDValue getEntryNode() const {
330 return SDValue(const_cast<SDNode *>(&EntryNode), 0);
333 /// Set the current root tag of the SelectionDAG.
335 const SDValue &setRoot(SDValue N) {
336 assert((!N.getNode() || N.getValueType() == MVT::Other) &&
337 "DAG root value is not a chain!");
339 checkForCycles(N.getNode(), this);
342 checkForCycles(this);
346 /// This iterates over the nodes in the SelectionDAG, folding
347 /// certain types of nodes together, or eliminating superfluous nodes. The
348 /// Level argument controls whether Combine is allowed to produce nodes and
349 /// types that are illegal on the target.
350 void Combine(CombineLevel Level, AliasAnalysis &AA,
351 CodeGenOpt::Level OptLevel);
353 /// This transforms the SelectionDAG into a SelectionDAG that
354 /// only uses types natively supported by the target.
355 /// Returns "true" if it made any changes.
357 /// Note that this is an involved process that may invalidate pointers into
359 bool LegalizeTypes();
361 /// This transforms the SelectionDAG into a SelectionDAG that is
362 /// compatible with the target instruction selector, as indicated by the
363 /// TargetLowering object.
365 /// Note that this is an involved process that may invalidate pointers into
369 /// \brief Transforms a SelectionDAG node and any operands to it into a node
370 /// that is compatible with the target instruction selector, as indicated by
371 /// the TargetLowering object.
373 /// \returns true if \c N is a valid, legal node after calling this.
375 /// This essentially runs a single recursive walk of the \c Legalize process
376 /// over the given node (and its operands). This can be used to incrementally
377 /// legalize the DAG. All of the nodes which are directly replaced,
378 /// potentially including N, are added to the output parameter \c
379 /// UpdatedNodes so that the delta to the DAG can be understood by the
382 /// When this returns false, N has been legalized in a way that make the
383 /// pointer passed in no longer valid. It may have even been deleted from the
384 /// DAG, and so it shouldn't be used further. When this returns true, the
385 /// N passed in is a legal node, and can be immediately processed as such.
386 /// This may still have done some work on the DAG, and will still populate
387 /// UpdatedNodes with any new nodes replacing those originally in the DAG.
388 bool LegalizeOp(SDNode *N, SmallSetVector<SDNode *, 16> &UpdatedNodes);
390 /// This transforms the SelectionDAG into a SelectionDAG
391 /// that only uses vector math operations supported by the target. This is
392 /// necessary as a separate step from Legalize because unrolling a vector
393 /// operation can introduce illegal types, which requires running
394 /// LegalizeTypes again.
396 /// This returns true if it made any changes; in that case, LegalizeTypes
397 /// is called again before Legalize.
399 /// Note that this is an involved process that may invalidate pointers into
401 bool LegalizeVectors();
403 /// This method deletes all unreachable nodes in the SelectionDAG.
404 void RemoveDeadNodes();
406 /// Remove the specified node from the system. This node must
407 /// have no referrers.
408 void DeleteNode(SDNode *N);
410 /// Return an SDVTList that represents the list of values specified.
411 SDVTList getVTList(EVT VT);
412 SDVTList getVTList(EVT VT1, EVT VT2);
413 SDVTList getVTList(EVT VT1, EVT VT2, EVT VT3);
414 SDVTList getVTList(EVT VT1, EVT VT2, EVT VT3, EVT VT4);
415 SDVTList getVTList(ArrayRef<EVT> VTs);
417 //===--------------------------------------------------------------------===//
418 // Node creation methods.
420 SDValue getConstant(uint64_t Val, SDLoc DL, EVT VT, bool isTarget = false,
421 bool isOpaque = false);
422 SDValue getConstant(const APInt &Val, SDLoc DL, EVT VT, bool isTarget = false,
423 bool isOpaque = false);
424 SDValue getConstant(const ConstantInt &Val, SDLoc DL, EVT VT,
425 bool isTarget = false, bool isOpaque = false);
426 SDValue getIntPtrConstant(uint64_t Val, SDLoc DL, bool isTarget = false);
427 SDValue getTargetConstant(uint64_t Val, SDLoc DL, EVT VT,
428 bool isOpaque = false) {
429 return getConstant(Val, DL, VT, true, isOpaque);
431 SDValue getTargetConstant(const APInt &Val, SDLoc DL, EVT VT,
432 bool isOpaque = false) {
433 return getConstant(Val, DL, VT, true, isOpaque);
435 SDValue getTargetConstant(const ConstantInt &Val, SDLoc DL, EVT VT,
436 bool isOpaque = false) {
437 return getConstant(Val, DL, VT, true, isOpaque);
439 // The forms below that take a double should only be used for simple
440 // constants that can be exactly represented in VT. No checks are made.
441 SDValue getConstantFP(double Val, SDLoc DL, EVT VT, bool isTarget = false);
442 SDValue getConstantFP(const APFloat& Val, SDLoc DL, EVT VT,
443 bool isTarget = false);
444 SDValue getConstantFP(const ConstantFP &CF, SDLoc DL, EVT VT,
445 bool isTarget = false);
446 SDValue getTargetConstantFP(double Val, SDLoc DL, EVT VT) {
447 return getConstantFP(Val, DL, VT, true);
449 SDValue getTargetConstantFP(const APFloat& Val, SDLoc DL, EVT VT) {
450 return getConstantFP(Val, DL, VT, true);
452 SDValue getTargetConstantFP(const ConstantFP &Val, SDLoc DL, EVT VT) {
453 return getConstantFP(Val, DL, VT, true);
455 SDValue getGlobalAddress(const GlobalValue *GV, SDLoc DL, EVT VT,
456 int64_t offset = 0, bool isTargetGA = false,
457 unsigned char TargetFlags = 0);
458 SDValue getTargetGlobalAddress(const GlobalValue *GV, SDLoc DL, EVT VT,
460 unsigned char TargetFlags = 0) {
461 return getGlobalAddress(GV, DL, VT, offset, true, TargetFlags);
463 SDValue getFrameIndex(int FI, EVT VT, bool isTarget = false);
464 SDValue getTargetFrameIndex(int FI, EVT VT) {
465 return getFrameIndex(FI, VT, true);
467 SDValue getJumpTable(int JTI, EVT VT, bool isTarget = false,
468 unsigned char TargetFlags = 0);
469 SDValue getTargetJumpTable(int JTI, EVT VT, unsigned char TargetFlags = 0) {
470 return getJumpTable(JTI, VT, true, TargetFlags);
472 SDValue getConstantPool(const Constant *C, EVT VT,
473 unsigned Align = 0, int Offs = 0, bool isT=false,
474 unsigned char TargetFlags = 0);
475 SDValue getTargetConstantPool(const Constant *C, EVT VT,
476 unsigned Align = 0, int Offset = 0,
477 unsigned char TargetFlags = 0) {
478 return getConstantPool(C, VT, Align, Offset, true, TargetFlags);
480 SDValue getConstantPool(MachineConstantPoolValue *C, EVT VT,
481 unsigned Align = 0, int Offs = 0, bool isT=false,
482 unsigned char TargetFlags = 0);
483 SDValue getTargetConstantPool(MachineConstantPoolValue *C,
484 EVT VT, unsigned Align = 0,
485 int Offset = 0, unsigned char TargetFlags=0) {
486 return getConstantPool(C, VT, Align, Offset, true, TargetFlags);
488 SDValue getTargetIndex(int Index, EVT VT, int64_t Offset = 0,
489 unsigned char TargetFlags = 0);
490 // When generating a branch to a BB, we don't in general know enough
491 // to provide debug info for the BB at that time, so keep this one around.
492 SDValue getBasicBlock(MachineBasicBlock *MBB);
493 SDValue getBasicBlock(MachineBasicBlock *MBB, SDLoc dl);
494 SDValue getExternalSymbol(const char *Sym, EVT VT);
495 SDValue getExternalSymbol(const char *Sym, SDLoc dl, EVT VT);
496 SDValue getTargetExternalSymbol(const char *Sym, EVT VT,
497 unsigned char TargetFlags = 0);
498 SDValue getValueType(EVT);
499 SDValue getRegister(unsigned Reg, EVT VT);
500 SDValue getRegisterMask(const uint32_t *RegMask);
501 SDValue getEHLabel(SDLoc dl, SDValue Root, MCSymbol *Label);
502 SDValue getBlockAddress(const BlockAddress *BA, EVT VT,
503 int64_t Offset = 0, bool isTarget = false,
504 unsigned char TargetFlags = 0);
505 SDValue getTargetBlockAddress(const BlockAddress *BA, EVT VT,
507 unsigned char TargetFlags = 0) {
508 return getBlockAddress(BA, VT, Offset, true, TargetFlags);
511 SDValue getCopyToReg(SDValue Chain, SDLoc dl, unsigned Reg, SDValue N) {
512 return getNode(ISD::CopyToReg, dl, MVT::Other, Chain,
513 getRegister(Reg, N.getValueType()), N);
516 // This version of the getCopyToReg method takes an extra operand, which
517 // indicates that there is potentially an incoming glue value (if Glue is not
518 // null) and that there should be a glue result.
519 SDValue getCopyToReg(SDValue Chain, SDLoc dl, unsigned Reg, SDValue N,
521 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
522 SDValue Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Glue };
523 return getNode(ISD::CopyToReg, dl, VTs,
524 ArrayRef<SDValue>(Ops, Glue.getNode() ? 4 : 3));
527 // Similar to last getCopyToReg() except parameter Reg is a SDValue
528 SDValue getCopyToReg(SDValue Chain, SDLoc dl, SDValue Reg, SDValue N,
530 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
531 SDValue Ops[] = { Chain, Reg, N, Glue };
532 return getNode(ISD::CopyToReg, dl, VTs,
533 ArrayRef<SDValue>(Ops, Glue.getNode() ? 4 : 3));
536 SDValue getCopyFromReg(SDValue Chain, SDLoc dl, unsigned Reg, EVT VT) {
537 SDVTList VTs = getVTList(VT, MVT::Other);
538 SDValue Ops[] = { Chain, getRegister(Reg, VT) };
539 return getNode(ISD::CopyFromReg, dl, VTs, Ops);
542 // This version of the getCopyFromReg method takes an extra operand, which
543 // indicates that there is potentially an incoming glue value (if Glue is not
544 // null) and that there should be a glue result.
545 SDValue getCopyFromReg(SDValue Chain, SDLoc dl, unsigned Reg, EVT VT,
547 SDVTList VTs = getVTList(VT, MVT::Other, MVT::Glue);
548 SDValue Ops[] = { Chain, getRegister(Reg, VT), Glue };
549 return getNode(ISD::CopyFromReg, dl, VTs,
550 ArrayRef<SDValue>(Ops, Glue.getNode() ? 3 : 2));
553 SDValue getCondCode(ISD::CondCode Cond);
555 /// Returns the ConvertRndSat Note: Avoid using this node because it may
556 /// disappear in the future and most targets don't support it.
557 SDValue getConvertRndSat(EVT VT, SDLoc dl, SDValue Val, SDValue DTy,
559 SDValue Rnd, SDValue Sat, ISD::CvtCode Code);
561 /// Return an ISD::VECTOR_SHUFFLE node. The number of elements in VT,
562 /// which must be a vector type, must match the number of mask elements
563 /// NumElts. An integer mask element equal to -1 is treated as undefined.
564 SDValue getVectorShuffle(EVT VT, SDLoc dl, SDValue N1, SDValue N2,
565 const int *MaskElts);
566 SDValue getVectorShuffle(EVT VT, SDLoc dl, SDValue N1, SDValue N2,
567 ArrayRef<int> MaskElts) {
568 assert(VT.getVectorNumElements() == MaskElts.size() &&
569 "Must have the same number of vector elements as mask elements!");
570 return getVectorShuffle(VT, dl, N1, N2, MaskElts.data());
573 /// \brief Returns an ISD::VECTOR_SHUFFLE node semantically equivalent to
574 /// the shuffle node in input but with swapped operands.
576 /// Example: shuffle A, B, <0,5,2,7> -> shuffle B, A, <4,1,6,3>
577 SDValue getCommutedVectorShuffle(const ShuffleVectorSDNode &SV);
579 /// Convert Op, which must be of integer type, to the
580 /// integer type VT, by either any-extending or truncating it.
581 SDValue getAnyExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
583 /// Convert Op, which must be of integer type, to the
584 /// integer type VT, by either sign-extending or truncating it.
585 SDValue getSExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
587 /// Convert Op, which must be of integer type, to the
588 /// integer type VT, by either zero-extending or truncating it.
589 SDValue getZExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
591 /// Return the expression required to zero extend the Op
592 /// value assuming it was the smaller SrcTy value.
593 SDValue getZeroExtendInReg(SDValue Op, SDLoc DL, EVT SrcTy);
595 /// Return an operation which will any-extend the low lanes of the operand
596 /// into the specified vector type. For example,
597 /// this can convert a v16i8 into a v4i32 by any-extending the low four
598 /// lanes of the operand from i8 to i32.
599 SDValue getAnyExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
601 /// Return an operation which will sign extend the low lanes of the operand
602 /// into the specified vector type. For example,
603 /// this can convert a v16i8 into a v4i32 by sign extending the low four
604 /// lanes of the operand from i8 to i32.
605 SDValue getSignExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
607 /// Return an operation which will zero extend the low lanes of the operand
608 /// into the specified vector type. For example,
609 /// this can convert a v16i8 into a v4i32 by zero extending the low four
610 /// lanes of the operand from i8 to i32.
611 SDValue getZeroExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
613 /// Convert Op, which must be of integer type, to the integer type VT,
614 /// by using an extension appropriate for the target's
615 /// BooleanContent for type OpVT or truncating it.
616 SDValue getBoolExtOrTrunc(SDValue Op, SDLoc SL, EVT VT, EVT OpVT);
618 /// Create a bitwise NOT operation as (XOR Val, -1).
619 SDValue getNOT(SDLoc DL, SDValue Val, EVT VT);
621 /// \brief Create a logical NOT operation as (XOR Val, BooleanOne).
622 SDValue getLogicalNOT(SDLoc DL, SDValue Val, EVT VT);
624 /// Return a new CALLSEQ_START node, which always must have a glue result
625 /// (to ensure it's not CSE'd). CALLSEQ_START does not have a useful SDLoc.
626 SDValue getCALLSEQ_START(SDValue Chain, SDValue Op, SDLoc DL) {
627 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
628 SDValue Ops[] = { Chain, Op };
629 return getNode(ISD::CALLSEQ_START, DL, VTs, Ops);
632 /// Return a new CALLSEQ_END node, which always must have a
633 /// glue result (to ensure it's not CSE'd).
634 /// CALLSEQ_END does not have a useful SDLoc.
635 SDValue getCALLSEQ_END(SDValue Chain, SDValue Op1, SDValue Op2,
636 SDValue InGlue, SDLoc DL) {
637 SDVTList NodeTys = getVTList(MVT::Other, MVT::Glue);
638 SmallVector<SDValue, 4> Ops;
639 Ops.push_back(Chain);
642 if (InGlue.getNode())
643 Ops.push_back(InGlue);
644 return getNode(ISD::CALLSEQ_END, DL, NodeTys, Ops);
647 /// Return an UNDEF node. UNDEF does not have a useful SDLoc.
648 SDValue getUNDEF(EVT VT) {
649 return getNode(ISD::UNDEF, SDLoc(), VT);
652 /// Return a GLOBAL_OFFSET_TABLE node. This does not have a useful SDLoc.
653 SDValue getGLOBAL_OFFSET_TABLE(EVT VT) {
654 return getNode(ISD::GLOBAL_OFFSET_TABLE, SDLoc(), VT);
657 /// Gets or creates the specified node.
659 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT,
660 ArrayRef<SDUse> Ops);
661 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT,
662 ArrayRef<SDValue> Ops);
663 SDValue getNode(unsigned Opcode, SDLoc DL, ArrayRef<EVT> ResultTys,
664 ArrayRef<SDValue> Ops);
665 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
666 ArrayRef<SDValue> Ops);
668 // Specialize based on number of operands.
669 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT);
670 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N);
671 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
672 bool nuw = false, bool nsw = false, bool exact = false);
673 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
675 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
676 SDValue N3, SDValue N4);
677 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
678 SDValue N3, SDValue N4, SDValue N5);
680 // Specialize again based on number of operands for nodes with a VTList
681 // rather than a single VT.
682 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs);
683 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N);
684 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N1,
686 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N1,
687 SDValue N2, SDValue N3);
688 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N1,
689 SDValue N2, SDValue N3, SDValue N4);
690 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N1,
691 SDValue N2, SDValue N3, SDValue N4, SDValue N5);
693 /// Compute a TokenFactor to force all the incoming stack arguments to be
694 /// loaded from the stack. This is used in tail call lowering to protect
695 /// stack arguments from being clobbered.
696 SDValue getStackArgumentTokenFactor(SDValue Chain);
698 SDValue getMemcpy(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
699 SDValue Size, unsigned Align, bool isVol, bool AlwaysInline,
700 bool isTailCall, MachinePointerInfo DstPtrInfo,
701 MachinePointerInfo SrcPtrInfo);
703 SDValue getMemmove(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
704 SDValue Size, unsigned Align, bool isVol, bool isTailCall,
705 MachinePointerInfo DstPtrInfo,
706 MachinePointerInfo SrcPtrInfo);
708 SDValue getMemset(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
709 SDValue Size, unsigned Align, bool isVol, bool isTailCall,
710 MachinePointerInfo DstPtrInfo);
712 /// Helper function to make it easier to build SetCC's if you just
713 /// have an ISD::CondCode instead of an SDValue.
715 SDValue getSetCC(SDLoc DL, EVT VT, SDValue LHS, SDValue RHS,
716 ISD::CondCode Cond) {
717 assert(LHS.getValueType().isVector() == RHS.getValueType().isVector() &&
718 "Cannot compare scalars to vectors");
719 assert(LHS.getValueType().isVector() == VT.isVector() &&
720 "Cannot compare scalars to vectors");
721 assert(Cond != ISD::SETCC_INVALID &&
722 "Cannot create a setCC of an invalid node.");
723 return getNode(ISD::SETCC, DL, VT, LHS, RHS, getCondCode(Cond));
726 /// Helper function to make it easier to build Select's if you just
727 /// have operands and don't want to check for vector.
728 SDValue getSelect(SDLoc DL, EVT VT, SDValue Cond,
729 SDValue LHS, SDValue RHS) {
730 assert(LHS.getValueType() == RHS.getValueType() &&
731 "Cannot use select on differing types");
732 assert(VT.isVector() == LHS.getValueType().isVector() &&
733 "Cannot mix vectors and scalars");
734 return getNode(Cond.getValueType().isVector() ? ISD::VSELECT : ISD::SELECT, DL, VT,
738 /// Helper function to make it easier to build SelectCC's if you
739 /// just have an ISD::CondCode instead of an SDValue.
741 SDValue getSelectCC(SDLoc DL, SDValue LHS, SDValue RHS,
742 SDValue True, SDValue False, ISD::CondCode Cond) {
743 return getNode(ISD::SELECT_CC, DL, True.getValueType(),
744 LHS, RHS, True, False, getCondCode(Cond));
747 /// VAArg produces a result and token chain, and takes a pointer
748 /// and a source value as input.
749 SDValue getVAArg(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
750 SDValue SV, unsigned Align);
752 /// Gets a node for an atomic cmpxchg op. There are two
753 /// valid Opcodes. ISD::ATOMIC_CMO_SWAP produces the value loaded and a
754 /// chain result. ISD::ATOMIC_CMP_SWAP_WITH_SUCCESS produces the value loaded,
755 /// a success flag (initially i1), and a chain.
756 SDValue getAtomicCmpSwap(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTs,
757 SDValue Chain, SDValue Ptr, SDValue Cmp, SDValue Swp,
758 MachinePointerInfo PtrInfo, unsigned Alignment,
759 AtomicOrdering SuccessOrdering,
760 AtomicOrdering FailureOrdering,
761 SynchronizationScope SynchScope);
762 SDValue getAtomicCmpSwap(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTs,
763 SDValue Chain, SDValue Ptr, SDValue Cmp, SDValue Swp,
764 MachineMemOperand *MMO,
765 AtomicOrdering SuccessOrdering,
766 AtomicOrdering FailureOrdering,
767 SynchronizationScope SynchScope);
769 /// Gets a node for an atomic op, produces result (if relevant)
770 /// and chain and takes 2 operands.
771 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDValue Chain,
772 SDValue Ptr, SDValue Val, const Value *PtrVal,
773 unsigned Alignment, AtomicOrdering Ordering,
774 SynchronizationScope SynchScope);
775 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDValue Chain,
776 SDValue Ptr, SDValue Val, MachineMemOperand *MMO,
777 AtomicOrdering Ordering,
778 SynchronizationScope SynchScope);
780 /// Gets a node for an atomic op, produces result and chain and
782 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, EVT VT,
783 SDValue Chain, SDValue Ptr, MachineMemOperand *MMO,
784 AtomicOrdering Ordering,
785 SynchronizationScope SynchScope);
787 /// Gets a node for an atomic op, produces result and chain and takes N
789 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTList,
790 ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
791 AtomicOrdering SuccessOrdering,
792 AtomicOrdering FailureOrdering,
793 SynchronizationScope SynchScope);
794 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTList,
795 ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
796 AtomicOrdering Ordering, SynchronizationScope SynchScope);
798 /// Creates a MemIntrinsicNode that may produce a
799 /// result and takes a list of operands. Opcode may be INTRINSIC_VOID,
800 /// INTRINSIC_W_CHAIN, or a target-specific opcode with a value not
801 /// less than FIRST_TARGET_MEMORY_OPCODE.
802 SDValue getMemIntrinsicNode(unsigned Opcode, SDLoc dl, SDVTList VTList,
803 ArrayRef<SDValue> Ops,
804 EVT MemVT, MachinePointerInfo PtrInfo,
805 unsigned Align = 0, bool Vol = false,
806 bool ReadMem = true, bool WriteMem = true,
809 SDValue getMemIntrinsicNode(unsigned Opcode, SDLoc dl, SDVTList VTList,
810 ArrayRef<SDValue> Ops,
811 EVT MemVT, MachineMemOperand *MMO);
813 /// Create a MERGE_VALUES node from the given operands.
814 SDValue getMergeValues(ArrayRef<SDValue> Ops, SDLoc dl);
816 /// Loads are not normal binary operators: their result type is not
817 /// determined by their operands, and they produce a value AND a token chain.
819 SDValue getLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
820 MachinePointerInfo PtrInfo, bool isVolatile,
821 bool isNonTemporal, bool isInvariant, unsigned Alignment,
822 const AAMDNodes &AAInfo = AAMDNodes(),
823 const MDNode *Ranges = nullptr);
824 SDValue getLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
825 MachineMemOperand *MMO);
826 SDValue getExtLoad(ISD::LoadExtType ExtType, SDLoc dl, EVT VT,
827 SDValue Chain, SDValue Ptr, MachinePointerInfo PtrInfo,
828 EVT MemVT, bool isVolatile,
829 bool isNonTemporal, bool isInvariant, unsigned Alignment,
830 const AAMDNodes &AAInfo = AAMDNodes());
831 SDValue getExtLoad(ISD::LoadExtType ExtType, SDLoc dl, EVT VT,
832 SDValue Chain, SDValue Ptr, EVT MemVT,
833 MachineMemOperand *MMO);
834 SDValue getIndexedLoad(SDValue OrigLoad, SDLoc dl, SDValue Base,
835 SDValue Offset, ISD::MemIndexedMode AM);
836 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
838 SDValue Chain, SDValue Ptr, SDValue Offset,
839 MachinePointerInfo PtrInfo, EVT MemVT,
840 bool isVolatile, bool isNonTemporal, bool isInvariant,
841 unsigned Alignment, const AAMDNodes &AAInfo = AAMDNodes(),
842 const MDNode *Ranges = nullptr);
843 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
845 SDValue Chain, SDValue Ptr, SDValue Offset,
846 EVT MemVT, MachineMemOperand *MMO);
848 /// Helper function to build ISD::STORE nodes.
849 SDValue getStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
850 MachinePointerInfo PtrInfo, bool isVolatile,
851 bool isNonTemporal, unsigned Alignment,
852 const AAMDNodes &AAInfo = AAMDNodes());
853 SDValue getStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
854 MachineMemOperand *MMO);
855 SDValue getTruncStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
856 MachinePointerInfo PtrInfo, EVT TVT,
857 bool isNonTemporal, bool isVolatile,
859 const AAMDNodes &AAInfo = AAMDNodes());
860 SDValue getTruncStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
861 EVT TVT, MachineMemOperand *MMO);
862 SDValue getIndexedStore(SDValue OrigStoe, SDLoc dl, SDValue Base,
863 SDValue Offset, ISD::MemIndexedMode AM);
865 SDValue getMaskedLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
866 SDValue Mask, SDValue Src0, EVT MemVT,
867 MachineMemOperand *MMO, ISD::LoadExtType);
868 SDValue getMaskedStore(SDValue Chain, SDLoc dl, SDValue Val,
869 SDValue Ptr, SDValue Mask, EVT MemVT,
870 MachineMemOperand *MMO, bool IsTrunc);
871 SDValue getMaskedGather(SDVTList VTs, EVT VT, SDLoc dl,
872 ArrayRef<SDValue> Ops, MachineMemOperand *MMO);
873 SDValue getMaskedScatter(SDVTList VTs, EVT VT, SDLoc dl,
874 ArrayRef<SDValue> Ops, MachineMemOperand *MMO);
875 /// Construct a node to track a Value* through the backend.
876 SDValue getSrcValue(const Value *v);
878 /// Return an MDNodeSDNode which holds an MDNode.
879 SDValue getMDNode(const MDNode *MD);
881 /// Return an AddrSpaceCastSDNode.
882 SDValue getAddrSpaceCast(SDLoc dl, EVT VT, SDValue Ptr,
883 unsigned SrcAS, unsigned DestAS);
885 /// Return the specified value casted to
886 /// the target's desired shift amount type.
887 SDValue getShiftAmountOperand(EVT LHSTy, SDValue Op);
889 /// *Mutate* the specified node in-place to have the
890 /// specified operands. If the resultant node already exists in the DAG,
891 /// this does not modify the specified node, instead it returns the node that
892 /// already exists. If the resultant node does not exist in the DAG, the
893 /// input node is returned. As a degenerate case, if you specify the same
894 /// input operands as the node already has, the input node is returned.
895 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op);
896 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2);
897 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
899 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
900 SDValue Op3, SDValue Op4);
901 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
902 SDValue Op3, SDValue Op4, SDValue Op5);
903 SDNode *UpdateNodeOperands(SDNode *N, ArrayRef<SDValue> Ops);
905 /// These are used for target selectors to *mutate* the
906 /// specified node to have the specified return type, Target opcode, and
907 /// operands. Note that target opcodes are stored as
908 /// ~TargetOpcode in the node opcode field. The resultant node is returned.
909 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT);
910 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT, SDValue Op1);
911 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
912 SDValue Op1, SDValue Op2);
913 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
914 SDValue Op1, SDValue Op2, SDValue Op3);
915 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
916 ArrayRef<SDValue> Ops);
917 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1, EVT VT2);
918 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
919 EVT VT2, ArrayRef<SDValue> Ops);
920 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
921 EVT VT2, EVT VT3, ArrayRef<SDValue> Ops);
922 SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT1,
923 EVT VT2, EVT VT3, EVT VT4, ArrayRef<SDValue> Ops);
924 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
925 EVT VT2, SDValue Op1);
926 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
927 EVT VT2, SDValue Op1, SDValue Op2);
928 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
929 EVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
930 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
931 EVT VT2, EVT VT3, SDValue Op1, SDValue Op2, SDValue Op3);
932 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
933 ArrayRef<SDValue> Ops);
935 /// This *mutates* the specified node to have the specified
936 /// return type, opcode, and operands.
937 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
938 ArrayRef<SDValue> Ops);
940 /// These are used for target selectors to create a new node
941 /// with specified return type(s), MachineInstr opcode, and operands.
943 /// Note that getMachineNode returns the resultant node. If there is already
944 /// a node of the specified opcode and operands, it returns that node instead
945 /// of the current one.
946 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT);
947 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
949 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
950 SDValue Op1, SDValue Op2);
951 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
952 SDValue Op1, SDValue Op2, SDValue Op3);
953 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
954 ArrayRef<SDValue> Ops);
955 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2);
956 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
958 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
959 SDValue Op1, SDValue Op2);
960 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
961 SDValue Op1, SDValue Op2, SDValue Op3);
962 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
963 ArrayRef<SDValue> Ops);
964 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
965 EVT VT3, SDValue Op1, SDValue Op2);
966 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
967 EVT VT3, SDValue Op1, SDValue Op2,
969 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
970 EVT VT3, ArrayRef<SDValue> Ops);
971 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
972 EVT VT3, EVT VT4, ArrayRef<SDValue> Ops);
973 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl,
974 ArrayRef<EVT> ResultTys,
975 ArrayRef<SDValue> Ops);
976 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, SDVTList VTs,
977 ArrayRef<SDValue> Ops);
979 /// A convenience function for creating TargetInstrInfo::EXTRACT_SUBREG nodes.
980 SDValue getTargetExtractSubreg(int SRIdx, SDLoc DL, EVT VT,
983 /// A convenience function for creating TargetInstrInfo::INSERT_SUBREG nodes.
984 SDValue getTargetInsertSubreg(int SRIdx, SDLoc DL, EVT VT,
985 SDValue Operand, SDValue Subreg);
987 /// Get the specified node if it's already available, or else return NULL.
988 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs, ArrayRef<SDValue> Ops,
989 bool nuw = false, bool nsw = false,
992 /// Creates a SDDbgValue node.
993 SDDbgValue *getDbgValue(MDNode *Var, MDNode *Expr, SDNode *N, unsigned R,
994 bool IsIndirect, uint64_t Off, DebugLoc DL,
998 SDDbgValue *getConstantDbgValue(MDNode *Var, MDNode *Expr, const Value *C,
999 uint64_t Off, DebugLoc DL, unsigned O);
1002 SDDbgValue *getFrameIndexDbgValue(MDNode *Var, MDNode *Expr, unsigned FI,
1003 uint64_t Off, DebugLoc DL, unsigned O);
1005 /// Remove the specified node from the system. If any of its
1006 /// operands then becomes dead, remove them as well. Inform UpdateListener
1007 /// for each node deleted.
1008 void RemoveDeadNode(SDNode *N);
1010 /// This method deletes the unreachable nodes in the
1011 /// given list, and any nodes that become unreachable as a result.
1012 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes);
1014 /// Modify anything using 'From' to use 'To' instead.
1015 /// This can cause recursive merging of nodes in the DAG. Use the first
1016 /// version if 'From' is known to have a single result, use the second
1017 /// if you have two nodes with identical results (or if 'To' has a superset
1018 /// of the results of 'From'), use the third otherwise.
1020 /// These methods all take an optional UpdateListener, which (if not null) is
1021 /// informed about nodes that are deleted and modified due to recursive
1022 /// changes in the dag.
1024 /// These functions only replace all existing uses. It's possible that as
1025 /// these replacements are being performed, CSE may cause the From node
1026 /// to be given new uses. These new uses of From are left in place, and
1027 /// not automatically transferred to To.
1029 void ReplaceAllUsesWith(SDValue From, SDValue Op);
1030 void ReplaceAllUsesWith(SDNode *From, SDNode *To);
1031 void ReplaceAllUsesWith(SDNode *From, const SDValue *To);
1033 /// Replace any uses of From with To, leaving
1034 /// uses of other values produced by From.Val alone.
1035 void ReplaceAllUsesOfValueWith(SDValue From, SDValue To);
1037 /// Like ReplaceAllUsesOfValueWith, but for multiple values at once.
1038 /// This correctly handles the case where
1039 /// there is an overlap between the From values and the To values.
1040 void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To,
1043 /// Topological-sort the AllNodes list and a
1044 /// assign a unique node id for each node in the DAG based on their
1045 /// topological order. Returns the number of nodes.
1046 unsigned AssignTopologicalOrder();
1048 /// Move node N in the AllNodes list to be immediately
1049 /// before the given iterator Position. This may be used to update the
1050 /// topological ordering when the list of nodes is modified.
1051 void RepositionNode(allnodes_iterator Position, SDNode *N) {
1052 AllNodes.insert(Position, AllNodes.remove(N));
1055 /// Returns true if the opcode is a commutative binary operation.
1056 static bool isCommutativeBinOp(unsigned Opcode) {
1057 // FIXME: This should get its info from the td file, so that we can include
1064 case ISD::SMUL_LOHI:
1065 case ISD::UMUL_LOHI:
1078 default: return false;
1082 /// Returns an APFloat semantics tag appropriate for the given type. If VT is
1083 /// a vector type, the element semantics are returned.
1084 static const fltSemantics &EVTToAPFloatSemantics(EVT VT) {
1085 switch (VT.getScalarType().getSimpleVT().SimpleTy) {
1086 default: llvm_unreachable("Unknown FP format");
1087 case MVT::f16: return APFloat::IEEEhalf;
1088 case MVT::f32: return APFloat::IEEEsingle;
1089 case MVT::f64: return APFloat::IEEEdouble;
1090 case MVT::f80: return APFloat::x87DoubleExtended;
1091 case MVT::f128: return APFloat::IEEEquad;
1092 case MVT::ppcf128: return APFloat::PPCDoubleDouble;
1096 /// Add a dbg_value SDNode. If SD is non-null that means the
1097 /// value is produced by SD.
1098 void AddDbgValue(SDDbgValue *DB, SDNode *SD, bool isParameter);
1100 /// Get the debug values which reference the given SDNode.
1101 ArrayRef<SDDbgValue*> GetDbgValues(const SDNode* SD) {
1102 return DbgInfo->getSDDbgValues(SD);
1105 /// Transfer SDDbgValues.
1106 void TransferDbgValues(SDValue From, SDValue To);
1108 /// Return true if there are any SDDbgValue nodes associated
1109 /// with this SelectionDAG.
1110 bool hasDebugValues() const { return !DbgInfo->empty(); }
1112 SDDbgInfo::DbgIterator DbgBegin() { return DbgInfo->DbgBegin(); }
1113 SDDbgInfo::DbgIterator DbgEnd() { return DbgInfo->DbgEnd(); }
1114 SDDbgInfo::DbgIterator ByvalParmDbgBegin() {
1115 return DbgInfo->ByvalParmDbgBegin();
1117 SDDbgInfo::DbgIterator ByvalParmDbgEnd() {
1118 return DbgInfo->ByvalParmDbgEnd();
1123 /// Create a stack temporary, suitable for holding the
1124 /// specified value type. If minAlign is specified, the slot size will have
1125 /// at least that alignment.
1126 SDValue CreateStackTemporary(EVT VT, unsigned minAlign = 1);
1128 /// Create a stack temporary suitable for holding
1129 /// either of the specified value types.
1130 SDValue CreateStackTemporary(EVT VT1, EVT VT2);
1132 SDValue FoldConstantArithmetic(unsigned Opcode, SDLoc DL, EVT VT,
1133 SDNode *Cst1, SDNode *Cst2);
1135 SDValue FoldConstantArithmetic(unsigned Opcode, SDLoc DL, EVT VT,
1136 const ConstantSDNode *Cst1,
1137 const ConstantSDNode *Cst2);
1139 /// Constant fold a setcc to true or false.
1140 SDValue FoldSetCC(EVT VT, SDValue N1,
1141 SDValue N2, ISD::CondCode Cond, SDLoc dl);
1143 /// Return true if the sign bit of Op is known to be zero.
1144 /// We use this predicate to simplify operations downstream.
1145 bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const;
1147 /// Return true if 'Op & Mask' is known to be zero. We
1148 /// use this predicate to simplify operations downstream. Op and Mask are
1149 /// known to be the same type.
1150 bool MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth = 0)
1153 /// Determine which bits of Op are known to be either zero or one and return
1154 /// them in the KnownZero/KnownOne bitsets. Targets can implement the
1155 /// computeKnownBitsForTargetNode method in the TargetLowering class to allow
1156 /// target nodes to be understood.
1157 void computeKnownBits(SDValue Op, APInt &KnownZero, APInt &KnownOne,
1158 unsigned Depth = 0) const;
1160 /// Return the number of times the sign bit of the
1161 /// register is replicated into the other bits. We know that at least 1 bit
1162 /// is always equal to the sign bit (itself), but other cases can give us
1163 /// information. For example, immediately after an "SRA X, 2", we know that
1164 /// the top 3 bits are all equal to each other, so we return 3. Targets can
1165 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
1166 /// class to allow target nodes to be understood.
1167 unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const;
1169 /// Return true if the specified operand is an
1170 /// ISD::ADD with a ConstantSDNode on the right-hand side, or if it is an
1171 /// ISD::OR with a ConstantSDNode that is guaranteed to have the same
1172 /// semantics as an ADD. This handles the equivalence:
1173 /// X|Cst == X+Cst iff X&Cst = 0.
1174 bool isBaseWithConstantOffset(SDValue Op) const;
1176 /// Test whether the given SDValue is known to never be NaN.
1177 bool isKnownNeverNaN(SDValue Op) const;
1179 /// Test whether the given SDValue is known to never be
1180 /// positive or negative Zero.
1181 bool isKnownNeverZero(SDValue Op) const;
1183 /// Test whether two SDValues are known to compare equal. This
1184 /// is true if they are the same value, or if one is negative zero and the
1185 /// other positive zero.
1186 bool isEqualTo(SDValue A, SDValue B) const;
1188 /// Utility function used by legalize and lowering to
1189 /// "unroll" a vector operation by splitting out the scalars and operating
1190 /// on each element individually. If the ResNE is 0, fully unroll the vector
1191 /// op. If ResNE is less than the width of the vector op, unroll up to ResNE.
1192 /// If the ResNE is greater than the width of the vector op, unroll the
1193 /// vector op and fill the end of the resulting vector with UNDEFS.
1194 SDValue UnrollVectorOp(SDNode *N, unsigned ResNE = 0);
1196 /// Return true if LD is loading 'Bytes' bytes from a location that is 'Dist'
1197 /// units away from the location that the 'Base' load is loading from.
1198 bool isConsecutiveLoad(LoadSDNode *LD, LoadSDNode *Base,
1199 unsigned Bytes, int Dist) const;
1201 /// Infer alignment of a load / store address. Return 0 if
1202 /// it cannot be inferred.
1203 unsigned InferPtrAlignment(SDValue Ptr) const;
1205 /// Compute the VTs needed for the low/hi parts of a type
1206 /// which is split (or expanded) into two not necessarily identical pieces.
1207 std::pair<EVT, EVT> GetSplitDestVTs(const EVT &VT) const;
1209 /// Split the vector with EXTRACT_SUBVECTOR using the provides
1210 /// VTs and return the low/high part.
1211 std::pair<SDValue, SDValue> SplitVector(const SDValue &N, const SDLoc &DL,
1212 const EVT &LoVT, const EVT &HiVT);
1214 /// Split the vector with EXTRACT_SUBVECTOR and return the low/high part.
1215 std::pair<SDValue, SDValue> SplitVector(const SDValue &N, const SDLoc &DL) {
1217 std::tie(LoVT, HiVT) = GetSplitDestVTs(N.getValueType());
1218 return SplitVector(N, DL, LoVT, HiVT);
1221 /// Split the node's operand with EXTRACT_SUBVECTOR and
1222 /// return the low/high part.
1223 std::pair<SDValue, SDValue> SplitVectorOperand(const SDNode *N, unsigned OpNo)
1225 return SplitVector(N->getOperand(OpNo), SDLoc(N));
1228 /// Append the extracted elements from Start to Count out of the vector Op
1229 /// in Args. If Count is 0, all of the elements will be extracted.
1230 void ExtractVectorElements(SDValue Op, SmallVectorImpl<SDValue> &Args,
1231 unsigned Start = 0, unsigned Count = 0);
1233 unsigned getEVTAlignment(EVT MemoryVT) const;
1236 void InsertNode(SDNode *N);
1237 bool RemoveNodeFromCSEMaps(SDNode *N);
1238 void AddModifiedNodeToCSEMaps(SDNode *N);
1239 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos);
1240 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2,
1242 SDNode *FindModifiedNodeSlot(SDNode *N, ArrayRef<SDValue> Ops,
1244 SDNode *UpdadeSDLocOnMergedSDNode(SDNode *N, SDLoc loc);
1246 void DeleteNodeNotInCSEMaps(SDNode *N);
1247 void DeallocateNode(SDNode *N);
1249 void allnodes_clear();
1251 BinarySDNode *GetBinarySDNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
1252 SDValue N1, SDValue N2, bool nuw, bool nsw,
1255 /// Look up the node specified by ID in CSEMap. If it exists, return it. If
1256 /// not, return the insertion token that will make insertion faster. This
1257 /// overload is for nodes other than Constant or ConstantFP, use the other one
1259 SDNode *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos);
1261 /// Look up the node specified by ID in CSEMap. If it exists, return it. If
1262 /// not, return the insertion token that will make insertion faster. Performs
1263 /// additional processing for constant nodes.
1264 SDNode *FindNodeOrInsertPos(const FoldingSetNodeID &ID, DebugLoc DL,
1267 /// List of non-single value types.
1268 FoldingSet<SDVTListNode> VTListMap;
1270 /// Maps to auto-CSE operations.
1271 std::vector<CondCodeSDNode*> CondCodeNodes;
1273 std::vector<SDNode*> ValueTypeNodes;
1274 std::map<EVT, SDNode*, EVT::compareRawBits> ExtendedValueTypeNodes;
1275 StringMap<SDNode*> ExternalSymbols;
1277 std::map<std::pair<std::string, unsigned char>,SDNode*> TargetExternalSymbols;
1280 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
1281 typedef SelectionDAG::allnodes_iterator nodes_iterator;
1282 static nodes_iterator nodes_begin(SelectionDAG *G) {
1283 return G->allnodes_begin();
1285 static nodes_iterator nodes_end(SelectionDAG *G) {
1286 return G->allnodes_end();
1290 } // end namespace llvm