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 DataLayout &getDataLayout() const { return MF->getDataLayout(); }
285 const TargetMachine &getTarget() const { return TM; }
286 const TargetSubtargetInfo &getSubtarget() const { return MF->getSubtarget(); }
287 const TargetLowering &getTargetLoweringInfo() const { return *TLI; }
288 const TargetSelectionDAGInfo &getSelectionDAGInfo() const { return *TSI; }
289 LLVMContext *getContext() const {return Context; }
291 /// Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
292 void viewGraph(const std::string &Title);
296 std::map<const SDNode *, std::string> NodeGraphAttrs;
299 /// Clear all previously defined node graph attributes.
300 /// Intended to be used from a debugging tool (eg. gdb).
301 void clearGraphAttrs();
303 /// Set graph attributes for a node. (eg. "color=red".)
304 void setGraphAttrs(const SDNode *N, const char *Attrs);
306 /// Get graph attributes for a node. (eg. "color=red".)
307 /// Used from getNodeAttributes.
308 const std::string getGraphAttrs(const SDNode *N) const;
310 /// Convenience for setting node color attribute.
311 void setGraphColor(const SDNode *N, const char *Color);
313 /// Convenience for setting subgraph color attribute.
314 void setSubgraphColor(SDNode *N, const char *Color);
316 typedef ilist<SDNode>::const_iterator allnodes_const_iterator;
317 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
318 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
319 typedef ilist<SDNode>::iterator allnodes_iterator;
320 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
321 allnodes_iterator allnodes_end() { return AllNodes.end(); }
322 ilist<SDNode>::size_type allnodes_size() const {
323 return AllNodes.size();
326 /// Return the root tag of the SelectionDAG.
327 const SDValue &getRoot() const { return Root; }
329 /// Return the token chain corresponding to the entry of the function.
330 SDValue getEntryNode() const {
331 return SDValue(const_cast<SDNode *>(&EntryNode), 0);
334 /// Set the current root tag of the SelectionDAG.
336 const SDValue &setRoot(SDValue N) {
337 assert((!N.getNode() || N.getValueType() == MVT::Other) &&
338 "DAG root value is not a chain!");
340 checkForCycles(N.getNode(), this);
343 checkForCycles(this);
347 /// This iterates over the nodes in the SelectionDAG, folding
348 /// certain types of nodes together, or eliminating superfluous nodes. The
349 /// Level argument controls whether Combine is allowed to produce nodes and
350 /// types that are illegal on the target.
351 void Combine(CombineLevel Level, AliasAnalysis &AA,
352 CodeGenOpt::Level OptLevel);
354 /// This transforms the SelectionDAG into a SelectionDAG that
355 /// only uses types natively supported by the target.
356 /// Returns "true" if it made any changes.
358 /// Note that this is an involved process that may invalidate pointers into
360 bool LegalizeTypes();
362 /// This transforms the SelectionDAG into a SelectionDAG that is
363 /// compatible with the target instruction selector, as indicated by the
364 /// TargetLowering object.
366 /// Note that this is an involved process that may invalidate pointers into
370 /// \brief Transforms a SelectionDAG node and any operands to it into a node
371 /// that is compatible with the target instruction selector, as indicated by
372 /// the TargetLowering object.
374 /// \returns true if \c N is a valid, legal node after calling this.
376 /// This essentially runs a single recursive walk of the \c Legalize process
377 /// over the given node (and its operands). This can be used to incrementally
378 /// legalize the DAG. All of the nodes which are directly replaced,
379 /// potentially including N, are added to the output parameter \c
380 /// UpdatedNodes so that the delta to the DAG can be understood by the
383 /// When this returns false, N has been legalized in a way that make the
384 /// pointer passed in no longer valid. It may have even been deleted from the
385 /// DAG, and so it shouldn't be used further. When this returns true, the
386 /// N passed in is a legal node, and can be immediately processed as such.
387 /// This may still have done some work on the DAG, and will still populate
388 /// UpdatedNodes with any new nodes replacing those originally in the DAG.
389 bool LegalizeOp(SDNode *N, SmallSetVector<SDNode *, 16> &UpdatedNodes);
391 /// This transforms the SelectionDAG into a SelectionDAG
392 /// that only uses vector math operations supported by the target. This is
393 /// necessary as a separate step from Legalize because unrolling a vector
394 /// operation can introduce illegal types, which requires running
395 /// LegalizeTypes again.
397 /// This returns true if it made any changes; in that case, LegalizeTypes
398 /// is called again before Legalize.
400 /// Note that this is an involved process that may invalidate pointers into
402 bool LegalizeVectors();
404 /// This method deletes all unreachable nodes in the SelectionDAG.
405 void RemoveDeadNodes();
407 /// Remove the specified node from the system. This node must
408 /// have no referrers.
409 void DeleteNode(SDNode *N);
411 /// Return an SDVTList that represents the list of values specified.
412 SDVTList getVTList(EVT VT);
413 SDVTList getVTList(EVT VT1, EVT VT2);
414 SDVTList getVTList(EVT VT1, EVT VT2, EVT VT3);
415 SDVTList getVTList(EVT VT1, EVT VT2, EVT VT3, EVT VT4);
416 SDVTList getVTList(ArrayRef<EVT> VTs);
418 //===--------------------------------------------------------------------===//
419 // Node creation methods.
421 SDValue getConstant(uint64_t Val, SDLoc DL, EVT VT, bool isTarget = false,
422 bool isOpaque = false);
423 SDValue getConstant(const APInt &Val, SDLoc DL, EVT VT, bool isTarget = false,
424 bool isOpaque = false);
425 SDValue getConstant(const ConstantInt &Val, SDLoc DL, EVT VT,
426 bool isTarget = false, bool isOpaque = false);
427 SDValue getIntPtrConstant(uint64_t Val, SDLoc DL, bool isTarget = false);
428 SDValue getTargetConstant(uint64_t Val, SDLoc DL, EVT VT,
429 bool isOpaque = false) {
430 return getConstant(Val, DL, VT, true, isOpaque);
432 SDValue getTargetConstant(const APInt &Val, SDLoc DL, EVT VT,
433 bool isOpaque = false) {
434 return getConstant(Val, DL, VT, true, isOpaque);
436 SDValue getTargetConstant(const ConstantInt &Val, SDLoc DL, EVT VT,
437 bool isOpaque = false) {
438 return getConstant(Val, DL, VT, true, isOpaque);
440 // The forms below that take a double should only be used for simple
441 // constants that can be exactly represented in VT. No checks are made.
442 SDValue getConstantFP(double Val, SDLoc DL, EVT VT, bool isTarget = false);
443 SDValue getConstantFP(const APFloat& Val, SDLoc DL, EVT VT,
444 bool isTarget = false);
445 SDValue getConstantFP(const ConstantFP &CF, SDLoc DL, EVT VT,
446 bool isTarget = false);
447 SDValue getTargetConstantFP(double Val, SDLoc DL, EVT VT) {
448 return getConstantFP(Val, DL, VT, true);
450 SDValue getTargetConstantFP(const APFloat& Val, SDLoc DL, EVT VT) {
451 return getConstantFP(Val, DL, VT, true);
453 SDValue getTargetConstantFP(const ConstantFP &Val, SDLoc DL, EVT VT) {
454 return getConstantFP(Val, DL, VT, true);
456 SDValue getGlobalAddress(const GlobalValue *GV, SDLoc DL, EVT VT,
457 int64_t offset = 0, bool isTargetGA = false,
458 unsigned char TargetFlags = 0);
459 SDValue getTargetGlobalAddress(const GlobalValue *GV, SDLoc DL, EVT VT,
461 unsigned char TargetFlags = 0) {
462 return getGlobalAddress(GV, DL, VT, offset, true, TargetFlags);
464 SDValue getFrameIndex(int FI, EVT VT, bool isTarget = false);
465 SDValue getTargetFrameIndex(int FI, EVT VT) {
466 return getFrameIndex(FI, VT, true);
468 SDValue getJumpTable(int JTI, EVT VT, bool isTarget = false,
469 unsigned char TargetFlags = 0);
470 SDValue getTargetJumpTable(int JTI, EVT VT, unsigned char TargetFlags = 0) {
471 return getJumpTable(JTI, VT, true, TargetFlags);
473 SDValue getConstantPool(const Constant *C, EVT VT,
474 unsigned Align = 0, int Offs = 0, bool isT=false,
475 unsigned char TargetFlags = 0);
476 SDValue getTargetConstantPool(const Constant *C, EVT VT,
477 unsigned Align = 0, int Offset = 0,
478 unsigned char TargetFlags = 0) {
479 return getConstantPool(C, VT, Align, Offset, true, TargetFlags);
481 SDValue getConstantPool(MachineConstantPoolValue *C, EVT VT,
482 unsigned Align = 0, int Offs = 0, bool isT=false,
483 unsigned char TargetFlags = 0);
484 SDValue getTargetConstantPool(MachineConstantPoolValue *C,
485 EVT VT, unsigned Align = 0,
486 int Offset = 0, unsigned char TargetFlags=0) {
487 return getConstantPool(C, VT, Align, Offset, true, TargetFlags);
489 SDValue getTargetIndex(int Index, EVT VT, int64_t Offset = 0,
490 unsigned char TargetFlags = 0);
491 // When generating a branch to a BB, we don't in general know enough
492 // to provide debug info for the BB at that time, so keep this one around.
493 SDValue getBasicBlock(MachineBasicBlock *MBB);
494 SDValue getBasicBlock(MachineBasicBlock *MBB, SDLoc dl);
495 SDValue getExternalSymbol(const char *Sym, EVT VT);
496 SDValue getExternalSymbol(const char *Sym, SDLoc dl, EVT VT);
497 SDValue getTargetExternalSymbol(const char *Sym, EVT VT,
498 unsigned char TargetFlags = 0);
499 SDValue getMCSymbol(MCSymbol *Sym, EVT VT);
501 SDValue getValueType(EVT);
502 SDValue getRegister(unsigned Reg, EVT VT);
503 SDValue getRegisterMask(const uint32_t *RegMask);
504 SDValue getEHLabel(SDLoc dl, SDValue Root, MCSymbol *Label);
505 SDValue getBlockAddress(const BlockAddress *BA, EVT VT,
506 int64_t Offset = 0, bool isTarget = false,
507 unsigned char TargetFlags = 0);
508 SDValue getTargetBlockAddress(const BlockAddress *BA, EVT VT,
510 unsigned char TargetFlags = 0) {
511 return getBlockAddress(BA, VT, Offset, true, TargetFlags);
514 SDValue getCopyToReg(SDValue Chain, SDLoc dl, unsigned Reg, SDValue N) {
515 return getNode(ISD::CopyToReg, dl, MVT::Other, Chain,
516 getRegister(Reg, N.getValueType()), N);
519 // This version of the getCopyToReg method takes an extra operand, which
520 // indicates that there is potentially an incoming glue value (if Glue is not
521 // null) and that there should be a glue result.
522 SDValue getCopyToReg(SDValue Chain, SDLoc dl, unsigned Reg, SDValue N,
524 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
525 SDValue Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Glue };
526 return getNode(ISD::CopyToReg, dl, VTs,
527 ArrayRef<SDValue>(Ops, Glue.getNode() ? 4 : 3));
530 // Similar to last getCopyToReg() except parameter Reg is a SDValue
531 SDValue getCopyToReg(SDValue Chain, SDLoc dl, SDValue Reg, SDValue N,
533 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
534 SDValue Ops[] = { Chain, Reg, N, Glue };
535 return getNode(ISD::CopyToReg, dl, VTs,
536 ArrayRef<SDValue>(Ops, Glue.getNode() ? 4 : 3));
539 SDValue getCopyFromReg(SDValue Chain, SDLoc dl, unsigned Reg, EVT VT) {
540 SDVTList VTs = getVTList(VT, MVT::Other);
541 SDValue Ops[] = { Chain, getRegister(Reg, VT) };
542 return getNode(ISD::CopyFromReg, dl, VTs, Ops);
545 // This version of the getCopyFromReg method takes an extra operand, which
546 // indicates that there is potentially an incoming glue value (if Glue is not
547 // null) and that there should be a glue result.
548 SDValue getCopyFromReg(SDValue Chain, SDLoc dl, unsigned Reg, EVT VT,
550 SDVTList VTs = getVTList(VT, MVT::Other, MVT::Glue);
551 SDValue Ops[] = { Chain, getRegister(Reg, VT), Glue };
552 return getNode(ISD::CopyFromReg, dl, VTs,
553 ArrayRef<SDValue>(Ops, Glue.getNode() ? 3 : 2));
556 SDValue getCondCode(ISD::CondCode Cond);
558 /// Returns the ConvertRndSat Note: Avoid using this node because it may
559 /// disappear in the future and most targets don't support it.
560 SDValue getConvertRndSat(EVT VT, SDLoc dl, SDValue Val, SDValue DTy,
562 SDValue Rnd, SDValue Sat, ISD::CvtCode Code);
564 /// Return an ISD::VECTOR_SHUFFLE node. The number of elements in VT,
565 /// which must be a vector type, must match the number of mask elements
566 /// NumElts. An integer mask element equal to -1 is treated as undefined.
567 SDValue getVectorShuffle(EVT VT, SDLoc dl, SDValue N1, SDValue N2,
568 const int *MaskElts);
569 SDValue getVectorShuffle(EVT VT, SDLoc dl, SDValue N1, SDValue N2,
570 ArrayRef<int> MaskElts) {
571 assert(VT.getVectorNumElements() == MaskElts.size() &&
572 "Must have the same number of vector elements as mask elements!");
573 return getVectorShuffle(VT, dl, N1, N2, MaskElts.data());
576 /// \brief Returns an ISD::VECTOR_SHUFFLE node semantically equivalent to
577 /// the shuffle node in input but with swapped operands.
579 /// Example: shuffle A, B, <0,5,2,7> -> shuffle B, A, <4,1,6,3>
580 SDValue getCommutedVectorShuffle(const ShuffleVectorSDNode &SV);
582 /// Convert Op, which must be of integer type, to the
583 /// integer type VT, by either any-extending or truncating it.
584 SDValue getAnyExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
586 /// Convert Op, which must be of integer type, to the
587 /// integer type VT, by either sign-extending or truncating it.
588 SDValue getSExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
590 /// Convert Op, which must be of integer type, to the
591 /// integer type VT, by either zero-extending or truncating it.
592 SDValue getZExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
594 /// Return the expression required to zero extend the Op
595 /// value assuming it was the smaller SrcTy value.
596 SDValue getZeroExtendInReg(SDValue Op, SDLoc DL, EVT SrcTy);
598 /// Return an operation which will any-extend the low lanes of the operand
599 /// into the specified vector type. For example,
600 /// this can convert a v16i8 into a v4i32 by any-extending the low four
601 /// lanes of the operand from i8 to i32.
602 SDValue getAnyExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
604 /// Return an operation which will sign extend the low lanes of the operand
605 /// into the specified vector type. For example,
606 /// this can convert a v16i8 into a v4i32 by sign extending the low four
607 /// lanes of the operand from i8 to i32.
608 SDValue getSignExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
610 /// Return an operation which will zero extend the low lanes of the operand
611 /// into the specified vector type. For example,
612 /// this can convert a v16i8 into a v4i32 by zero extending the low four
613 /// lanes of the operand from i8 to i32.
614 SDValue getZeroExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
616 /// Convert Op, which must be of integer type, to the integer type VT,
617 /// by using an extension appropriate for the target's
618 /// BooleanContent for type OpVT or truncating it.
619 SDValue getBoolExtOrTrunc(SDValue Op, SDLoc SL, EVT VT, EVT OpVT);
621 /// Create a bitwise NOT operation as (XOR Val, -1).
622 SDValue getNOT(SDLoc DL, SDValue Val, EVT VT);
624 /// \brief Create a logical NOT operation as (XOR Val, BooleanOne).
625 SDValue getLogicalNOT(SDLoc DL, SDValue Val, EVT VT);
627 /// Return a new CALLSEQ_START node, which always must have a glue result
628 /// (to ensure it's not CSE'd). CALLSEQ_START does not have a useful SDLoc.
629 SDValue getCALLSEQ_START(SDValue Chain, SDValue Op, SDLoc DL) {
630 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
631 SDValue Ops[] = { Chain, Op };
632 return getNode(ISD::CALLSEQ_START, DL, VTs, Ops);
635 /// Return a new CALLSEQ_END node, which always must have a
636 /// glue result (to ensure it's not CSE'd).
637 /// CALLSEQ_END does not have a useful SDLoc.
638 SDValue getCALLSEQ_END(SDValue Chain, SDValue Op1, SDValue Op2,
639 SDValue InGlue, SDLoc DL) {
640 SDVTList NodeTys = getVTList(MVT::Other, MVT::Glue);
641 SmallVector<SDValue, 4> Ops;
642 Ops.push_back(Chain);
645 if (InGlue.getNode())
646 Ops.push_back(InGlue);
647 return getNode(ISD::CALLSEQ_END, DL, NodeTys, Ops);
650 /// Return an UNDEF node. UNDEF does not have a useful SDLoc.
651 SDValue getUNDEF(EVT VT) {
652 return getNode(ISD::UNDEF, SDLoc(), VT);
655 /// Return a GLOBAL_OFFSET_TABLE node. This does not have a useful SDLoc.
656 SDValue getGLOBAL_OFFSET_TABLE(EVT VT) {
657 return getNode(ISD::GLOBAL_OFFSET_TABLE, SDLoc(), VT);
660 /// Gets or creates the specified node.
662 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT,
663 ArrayRef<SDUse> Ops);
664 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT,
665 ArrayRef<SDValue> Ops);
666 SDValue getNode(unsigned Opcode, SDLoc DL, ArrayRef<EVT> ResultTys,
667 ArrayRef<SDValue> Ops);
668 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
669 ArrayRef<SDValue> Ops);
671 // Specialize based on number of operands.
672 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT);
673 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N);
674 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
675 const SDNodeFlags *Flags = nullptr);
676 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
678 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
679 SDValue N3, SDValue N4);
680 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
681 SDValue N3, SDValue N4, SDValue N5);
683 // Specialize again based on number of operands for nodes with a VTList
684 // rather than a single VT.
685 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs);
686 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N);
687 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N1,
689 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N1,
690 SDValue N2, SDValue N3);
691 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N1,
692 SDValue N2, SDValue N3, SDValue N4);
693 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N1,
694 SDValue N2, SDValue N3, SDValue N4, SDValue N5);
696 /// Compute a TokenFactor to force all the incoming stack arguments to be
697 /// loaded from the stack. This is used in tail call lowering to protect
698 /// stack arguments from being clobbered.
699 SDValue getStackArgumentTokenFactor(SDValue Chain);
701 SDValue getMemcpy(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
702 SDValue Size, unsigned Align, bool isVol, bool AlwaysInline,
703 bool isTailCall, MachinePointerInfo DstPtrInfo,
704 MachinePointerInfo SrcPtrInfo);
706 SDValue getMemmove(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
707 SDValue Size, unsigned Align, bool isVol, bool isTailCall,
708 MachinePointerInfo DstPtrInfo,
709 MachinePointerInfo SrcPtrInfo);
711 SDValue getMemset(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
712 SDValue Size, unsigned Align, bool isVol, bool isTailCall,
713 MachinePointerInfo DstPtrInfo);
715 /// Helper function to make it easier to build SetCC's if you just
716 /// have an ISD::CondCode instead of an SDValue.
718 SDValue getSetCC(SDLoc DL, EVT VT, SDValue LHS, SDValue RHS,
719 ISD::CondCode Cond) {
720 assert(LHS.getValueType().isVector() == RHS.getValueType().isVector() &&
721 "Cannot compare scalars to vectors");
722 assert(LHS.getValueType().isVector() == VT.isVector() &&
723 "Cannot compare scalars to vectors");
724 assert(Cond != ISD::SETCC_INVALID &&
725 "Cannot create a setCC of an invalid node.");
726 return getNode(ISD::SETCC, DL, VT, LHS, RHS, getCondCode(Cond));
729 /// Helper function to make it easier to build Select's if you just
730 /// have operands and don't want to check for vector.
731 SDValue getSelect(SDLoc DL, EVT VT, SDValue Cond,
732 SDValue LHS, SDValue RHS) {
733 assert(LHS.getValueType() == RHS.getValueType() &&
734 "Cannot use select on differing types");
735 assert(VT.isVector() == LHS.getValueType().isVector() &&
736 "Cannot mix vectors and scalars");
737 return getNode(Cond.getValueType().isVector() ? ISD::VSELECT : ISD::SELECT, DL, VT,
741 /// Helper function to make it easier to build SelectCC's if you
742 /// just have an ISD::CondCode instead of an SDValue.
744 SDValue getSelectCC(SDLoc DL, SDValue LHS, SDValue RHS,
745 SDValue True, SDValue False, ISD::CondCode Cond) {
746 return getNode(ISD::SELECT_CC, DL, True.getValueType(),
747 LHS, RHS, True, False, getCondCode(Cond));
750 /// VAArg produces a result and token chain, and takes a pointer
751 /// and a source value as input.
752 SDValue getVAArg(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
753 SDValue SV, unsigned Align);
755 /// Gets a node for an atomic cmpxchg op. There are two
756 /// valid Opcodes. ISD::ATOMIC_CMO_SWAP produces the value loaded and a
757 /// chain result. ISD::ATOMIC_CMP_SWAP_WITH_SUCCESS produces the value loaded,
758 /// a success flag (initially i1), and a chain.
759 SDValue getAtomicCmpSwap(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTs,
760 SDValue Chain, SDValue Ptr, SDValue Cmp, SDValue Swp,
761 MachinePointerInfo PtrInfo, unsigned Alignment,
762 AtomicOrdering SuccessOrdering,
763 AtomicOrdering FailureOrdering,
764 SynchronizationScope SynchScope);
765 SDValue getAtomicCmpSwap(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTs,
766 SDValue Chain, SDValue Ptr, SDValue Cmp, SDValue Swp,
767 MachineMemOperand *MMO,
768 AtomicOrdering SuccessOrdering,
769 AtomicOrdering FailureOrdering,
770 SynchronizationScope SynchScope);
772 /// Gets a node for an atomic op, produces result (if relevant)
773 /// and chain and takes 2 operands.
774 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDValue Chain,
775 SDValue Ptr, SDValue Val, const Value *PtrVal,
776 unsigned Alignment, AtomicOrdering Ordering,
777 SynchronizationScope SynchScope);
778 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDValue Chain,
779 SDValue Ptr, SDValue Val, MachineMemOperand *MMO,
780 AtomicOrdering Ordering,
781 SynchronizationScope SynchScope);
783 /// Gets a node for an atomic op, produces result and chain and
785 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, EVT VT,
786 SDValue Chain, SDValue Ptr, MachineMemOperand *MMO,
787 AtomicOrdering Ordering,
788 SynchronizationScope SynchScope);
790 /// Gets a node for an atomic op, produces result and chain and takes N
792 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTList,
793 ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
794 AtomicOrdering SuccessOrdering,
795 AtomicOrdering FailureOrdering,
796 SynchronizationScope SynchScope);
797 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTList,
798 ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
799 AtomicOrdering Ordering, SynchronizationScope SynchScope);
801 /// Creates a MemIntrinsicNode that may produce a
802 /// result and takes a list of operands. Opcode may be INTRINSIC_VOID,
803 /// INTRINSIC_W_CHAIN, or a target-specific opcode with a value not
804 /// less than FIRST_TARGET_MEMORY_OPCODE.
805 SDValue getMemIntrinsicNode(unsigned Opcode, SDLoc dl, SDVTList VTList,
806 ArrayRef<SDValue> Ops,
807 EVT MemVT, MachinePointerInfo PtrInfo,
808 unsigned Align = 0, bool Vol = false,
809 bool ReadMem = true, bool WriteMem = true,
812 SDValue getMemIntrinsicNode(unsigned Opcode, SDLoc dl, SDVTList VTList,
813 ArrayRef<SDValue> Ops,
814 EVT MemVT, MachineMemOperand *MMO);
816 /// Create a MERGE_VALUES node from the given operands.
817 SDValue getMergeValues(ArrayRef<SDValue> Ops, SDLoc dl);
819 /// Loads are not normal binary operators: their result type is not
820 /// determined by their operands, and they produce a value AND a token chain.
822 SDValue getLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
823 MachinePointerInfo PtrInfo, bool isVolatile,
824 bool isNonTemporal, bool isInvariant, unsigned Alignment,
825 const AAMDNodes &AAInfo = AAMDNodes(),
826 const MDNode *Ranges = nullptr);
827 SDValue getLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
828 MachineMemOperand *MMO);
829 SDValue getExtLoad(ISD::LoadExtType ExtType, SDLoc dl, EVT VT,
830 SDValue Chain, SDValue Ptr, MachinePointerInfo PtrInfo,
831 EVT MemVT, bool isVolatile,
832 bool isNonTemporal, bool isInvariant, unsigned Alignment,
833 const AAMDNodes &AAInfo = AAMDNodes());
834 SDValue getExtLoad(ISD::LoadExtType ExtType, SDLoc dl, EVT VT,
835 SDValue Chain, SDValue Ptr, EVT MemVT,
836 MachineMemOperand *MMO);
837 SDValue getIndexedLoad(SDValue OrigLoad, SDLoc dl, SDValue Base,
838 SDValue Offset, ISD::MemIndexedMode AM);
839 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
841 SDValue Chain, SDValue Ptr, SDValue Offset,
842 MachinePointerInfo PtrInfo, EVT MemVT,
843 bool isVolatile, bool isNonTemporal, bool isInvariant,
844 unsigned Alignment, const AAMDNodes &AAInfo = AAMDNodes(),
845 const MDNode *Ranges = nullptr);
846 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
848 SDValue Chain, SDValue Ptr, SDValue Offset,
849 EVT MemVT, MachineMemOperand *MMO);
851 /// Helper function to build ISD::STORE nodes.
852 SDValue getStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
853 MachinePointerInfo PtrInfo, bool isVolatile,
854 bool isNonTemporal, unsigned Alignment,
855 const AAMDNodes &AAInfo = AAMDNodes());
856 SDValue getStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
857 MachineMemOperand *MMO);
858 SDValue getTruncStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
859 MachinePointerInfo PtrInfo, EVT TVT,
860 bool isNonTemporal, bool isVolatile,
862 const AAMDNodes &AAInfo = AAMDNodes());
863 SDValue getTruncStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
864 EVT TVT, MachineMemOperand *MMO);
865 SDValue getIndexedStore(SDValue OrigStoe, SDLoc dl, SDValue Base,
866 SDValue Offset, ISD::MemIndexedMode AM);
868 SDValue getMaskedLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
869 SDValue Mask, SDValue Src0, EVT MemVT,
870 MachineMemOperand *MMO, ISD::LoadExtType);
871 SDValue getMaskedStore(SDValue Chain, SDLoc dl, SDValue Val,
872 SDValue Ptr, SDValue Mask, EVT MemVT,
873 MachineMemOperand *MMO, bool IsTrunc);
874 SDValue getMaskedGather(SDVTList VTs, EVT VT, SDLoc dl,
875 ArrayRef<SDValue> Ops, MachineMemOperand *MMO);
876 SDValue getMaskedScatter(SDVTList VTs, EVT VT, SDLoc dl,
877 ArrayRef<SDValue> Ops, MachineMemOperand *MMO);
878 /// Construct a node to track a Value* through the backend.
879 SDValue getSrcValue(const Value *v);
881 /// Return an MDNodeSDNode which holds an MDNode.
882 SDValue getMDNode(const MDNode *MD);
884 /// Return a bitcast using the SDLoc of the value operand, and casting to the
885 /// provided type. Use getNode to set a custom SDLoc.
886 SDValue getBitcast(EVT VT, SDValue V);
888 /// Return an AddrSpaceCastSDNode.
889 SDValue getAddrSpaceCast(SDLoc dl, EVT VT, SDValue Ptr,
890 unsigned SrcAS, unsigned DestAS);
892 /// Return the specified value casted to
893 /// the target's desired shift amount type.
894 SDValue getShiftAmountOperand(EVT LHSTy, SDValue Op);
896 /// *Mutate* the specified node in-place to have the
897 /// specified operands. If the resultant node already exists in the DAG,
898 /// this does not modify the specified node, instead it returns the node that
899 /// already exists. If the resultant node does not exist in the DAG, the
900 /// input node is returned. As a degenerate case, if you specify the same
901 /// input operands as the node already has, the input node is returned.
902 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op);
903 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2);
904 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
906 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
907 SDValue Op3, SDValue Op4);
908 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
909 SDValue Op3, SDValue Op4, SDValue Op5);
910 SDNode *UpdateNodeOperands(SDNode *N, ArrayRef<SDValue> Ops);
912 /// These are used for target selectors to *mutate* the
913 /// specified node to have the specified return type, Target opcode, and
914 /// operands. Note that target opcodes are stored as
915 /// ~TargetOpcode in the node opcode field. The resultant node is returned.
916 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT);
917 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT, SDValue Op1);
918 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
919 SDValue Op1, SDValue Op2);
920 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
921 SDValue Op1, SDValue Op2, SDValue Op3);
922 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
923 ArrayRef<SDValue> Ops);
924 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1, EVT VT2);
925 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
926 EVT VT2, ArrayRef<SDValue> Ops);
927 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
928 EVT VT2, EVT VT3, ArrayRef<SDValue> Ops);
929 SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT1,
930 EVT VT2, EVT VT3, EVT VT4, ArrayRef<SDValue> Ops);
931 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
932 EVT VT2, SDValue Op1);
933 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
934 EVT VT2, SDValue Op1, SDValue Op2);
935 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
936 EVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
937 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
938 EVT VT2, EVT VT3, SDValue Op1, SDValue Op2, SDValue Op3);
939 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
940 ArrayRef<SDValue> Ops);
942 /// This *mutates* the specified node to have the specified
943 /// return type, opcode, and operands.
944 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
945 ArrayRef<SDValue> Ops);
947 /// These are used for target selectors to create a new node
948 /// with specified return type(s), MachineInstr opcode, and operands.
950 /// Note that getMachineNode returns the resultant node. If there is already
951 /// a node of the specified opcode and operands, it returns that node instead
952 /// of the current one.
953 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT);
954 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
956 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
957 SDValue Op1, SDValue Op2);
958 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
959 SDValue Op1, SDValue Op2, SDValue Op3);
960 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
961 ArrayRef<SDValue> Ops);
962 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2);
963 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
965 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
966 SDValue Op1, SDValue Op2);
967 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
968 SDValue Op1, SDValue Op2, SDValue Op3);
969 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
970 ArrayRef<SDValue> Ops);
971 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
972 EVT VT3, SDValue Op1, SDValue Op2);
973 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
974 EVT VT3, SDValue Op1, SDValue Op2,
976 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
977 EVT VT3, ArrayRef<SDValue> Ops);
978 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
979 EVT VT3, EVT VT4, ArrayRef<SDValue> Ops);
980 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl,
981 ArrayRef<EVT> ResultTys,
982 ArrayRef<SDValue> Ops);
983 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, SDVTList VTs,
984 ArrayRef<SDValue> Ops);
986 /// A convenience function for creating TargetInstrInfo::EXTRACT_SUBREG nodes.
987 SDValue getTargetExtractSubreg(int SRIdx, SDLoc DL, EVT VT,
990 /// A convenience function for creating TargetInstrInfo::INSERT_SUBREG nodes.
991 SDValue getTargetInsertSubreg(int SRIdx, SDLoc DL, EVT VT,
992 SDValue Operand, SDValue Subreg);
994 /// Get the specified node if it's already available, or else return NULL.
995 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs, ArrayRef<SDValue> Ops,
996 const SDNodeFlags *Flags = nullptr);
998 /// Creates a SDDbgValue node.
999 SDDbgValue *getDbgValue(MDNode *Var, MDNode *Expr, SDNode *N, unsigned R,
1000 bool IsIndirect, uint64_t Off, DebugLoc DL,
1004 SDDbgValue *getConstantDbgValue(MDNode *Var, MDNode *Expr, const Value *C,
1005 uint64_t Off, DebugLoc DL, unsigned O);
1008 SDDbgValue *getFrameIndexDbgValue(MDNode *Var, MDNode *Expr, unsigned FI,
1009 uint64_t Off, DebugLoc DL, unsigned O);
1011 /// Remove the specified node from the system. If any of its
1012 /// operands then becomes dead, remove them as well. Inform UpdateListener
1013 /// for each node deleted.
1014 void RemoveDeadNode(SDNode *N);
1016 /// This method deletes the unreachable nodes in the
1017 /// given list, and any nodes that become unreachable as a result.
1018 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes);
1020 /// Modify anything using 'From' to use 'To' instead.
1021 /// This can cause recursive merging of nodes in the DAG. Use the first
1022 /// version if 'From' is known to have a single result, use the second
1023 /// if you have two nodes with identical results (or if 'To' has a superset
1024 /// of the results of 'From'), use the third otherwise.
1026 /// These methods all take an optional UpdateListener, which (if not null) is
1027 /// informed about nodes that are deleted and modified due to recursive
1028 /// changes in the dag.
1030 /// These functions only replace all existing uses. It's possible that as
1031 /// these replacements are being performed, CSE may cause the From node
1032 /// to be given new uses. These new uses of From are left in place, and
1033 /// not automatically transferred to To.
1035 void ReplaceAllUsesWith(SDValue From, SDValue Op);
1036 void ReplaceAllUsesWith(SDNode *From, SDNode *To);
1037 void ReplaceAllUsesWith(SDNode *From, const SDValue *To);
1039 /// Replace any uses of From with To, leaving
1040 /// uses of other values produced by From.Val alone.
1041 void ReplaceAllUsesOfValueWith(SDValue From, SDValue To);
1043 /// Like ReplaceAllUsesOfValueWith, but for multiple values at once.
1044 /// This correctly handles the case where
1045 /// there is an overlap between the From values and the To values.
1046 void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To,
1049 /// Topological-sort the AllNodes list and a
1050 /// assign a unique node id for each node in the DAG based on their
1051 /// topological order. Returns the number of nodes.
1052 unsigned AssignTopologicalOrder();
1054 /// Move node N in the AllNodes list to be immediately
1055 /// before the given iterator Position. This may be used to update the
1056 /// topological ordering when the list of nodes is modified.
1057 void RepositionNode(allnodes_iterator Position, SDNode *N) {
1058 AllNodes.insert(Position, AllNodes.remove(N));
1061 /// Returns true if the opcode is a commutative binary operation.
1062 static bool isCommutativeBinOp(unsigned Opcode) {
1063 // FIXME: This should get its info from the td file, so that we can include
1070 case ISD::SMUL_LOHI:
1071 case ISD::UMUL_LOHI:
1084 default: return false;
1088 /// Returns an APFloat semantics tag appropriate for the given type. If VT is
1089 /// a vector type, the element semantics are returned.
1090 static const fltSemantics &EVTToAPFloatSemantics(EVT VT) {
1091 switch (VT.getScalarType().getSimpleVT().SimpleTy) {
1092 default: llvm_unreachable("Unknown FP format");
1093 case MVT::f16: return APFloat::IEEEhalf;
1094 case MVT::f32: return APFloat::IEEEsingle;
1095 case MVT::f64: return APFloat::IEEEdouble;
1096 case MVT::f80: return APFloat::x87DoubleExtended;
1097 case MVT::f128: return APFloat::IEEEquad;
1098 case MVT::ppcf128: return APFloat::PPCDoubleDouble;
1102 /// Add a dbg_value SDNode. If SD is non-null that means the
1103 /// value is produced by SD.
1104 void AddDbgValue(SDDbgValue *DB, SDNode *SD, bool isParameter);
1106 /// Get the debug values which reference the given SDNode.
1107 ArrayRef<SDDbgValue*> GetDbgValues(const SDNode* SD) {
1108 return DbgInfo->getSDDbgValues(SD);
1111 /// Transfer SDDbgValues.
1112 void TransferDbgValues(SDValue From, SDValue To);
1114 /// Return true if there are any SDDbgValue nodes associated
1115 /// with this SelectionDAG.
1116 bool hasDebugValues() const { return !DbgInfo->empty(); }
1118 SDDbgInfo::DbgIterator DbgBegin() { return DbgInfo->DbgBegin(); }
1119 SDDbgInfo::DbgIterator DbgEnd() { return DbgInfo->DbgEnd(); }
1120 SDDbgInfo::DbgIterator ByvalParmDbgBegin() {
1121 return DbgInfo->ByvalParmDbgBegin();
1123 SDDbgInfo::DbgIterator ByvalParmDbgEnd() {
1124 return DbgInfo->ByvalParmDbgEnd();
1129 /// Create a stack temporary, suitable for holding the
1130 /// specified value type. If minAlign is specified, the slot size will have
1131 /// at least that alignment.
1132 SDValue CreateStackTemporary(EVT VT, unsigned minAlign = 1);
1134 /// Create a stack temporary suitable for holding
1135 /// either of the specified value types.
1136 SDValue CreateStackTemporary(EVT VT1, EVT VT2);
1138 SDValue FoldConstantArithmetic(unsigned Opcode, SDLoc DL, EVT VT,
1139 SDNode *Cst1, SDNode *Cst2);
1141 SDValue FoldConstantArithmetic(unsigned Opcode, SDLoc DL, EVT VT,
1142 const ConstantSDNode *Cst1,
1143 const ConstantSDNode *Cst2);
1145 /// Constant fold a setcc to true or false.
1146 SDValue FoldSetCC(EVT VT, SDValue N1,
1147 SDValue N2, ISD::CondCode Cond, SDLoc dl);
1149 /// Return true if the sign bit of Op is known to be zero.
1150 /// We use this predicate to simplify operations downstream.
1151 bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const;
1153 /// Return true if 'Op & Mask' is known to be zero. We
1154 /// use this predicate to simplify operations downstream. Op and Mask are
1155 /// known to be the same type.
1156 bool MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth = 0)
1159 /// Determine which bits of Op are known to be either zero or one and return
1160 /// them in the KnownZero/KnownOne bitsets. Targets can implement the
1161 /// computeKnownBitsForTargetNode method in the TargetLowering class to allow
1162 /// target nodes to be understood.
1163 void computeKnownBits(SDValue Op, APInt &KnownZero, APInt &KnownOne,
1164 unsigned Depth = 0) const;
1166 /// Return the number of times the sign bit of the
1167 /// register is replicated into the other bits. We know that at least 1 bit
1168 /// is always equal to the sign bit (itself), but other cases can give us
1169 /// information. For example, immediately after an "SRA X, 2", we know that
1170 /// the top 3 bits are all equal to each other, so we return 3. Targets can
1171 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
1172 /// class to allow target nodes to be understood.
1173 unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const;
1175 /// Return true if the specified operand is an
1176 /// ISD::ADD with a ConstantSDNode on the right-hand side, or if it is an
1177 /// ISD::OR with a ConstantSDNode that is guaranteed to have the same
1178 /// semantics as an ADD. This handles the equivalence:
1179 /// X|Cst == X+Cst iff X&Cst = 0.
1180 bool isBaseWithConstantOffset(SDValue Op) const;
1182 /// Test whether the given SDValue is known to never be NaN.
1183 bool isKnownNeverNaN(SDValue Op) const;
1185 /// Test whether the given SDValue is known to never be
1186 /// positive or negative Zero.
1187 bool isKnownNeverZero(SDValue Op) const;
1189 /// Test whether two SDValues are known to compare equal. This
1190 /// is true if they are the same value, or if one is negative zero and the
1191 /// other positive zero.
1192 bool isEqualTo(SDValue A, SDValue B) const;
1194 /// Utility function used by legalize and lowering to
1195 /// "unroll" a vector operation by splitting out the scalars and operating
1196 /// on each element individually. If the ResNE is 0, fully unroll the vector
1197 /// op. If ResNE is less than the width of the vector op, unroll up to ResNE.
1198 /// If the ResNE is greater than the width of the vector op, unroll the
1199 /// vector op and fill the end of the resulting vector with UNDEFS.
1200 SDValue UnrollVectorOp(SDNode *N, unsigned ResNE = 0);
1202 /// Return true if LD is loading 'Bytes' bytes from a location that is 'Dist'
1203 /// units away from the location that the 'Base' load is loading from.
1204 bool isConsecutiveLoad(LoadSDNode *LD, LoadSDNode *Base,
1205 unsigned Bytes, int Dist) const;
1207 /// Infer alignment of a load / store address. Return 0 if
1208 /// it cannot be inferred.
1209 unsigned InferPtrAlignment(SDValue Ptr) const;
1211 /// Compute the VTs needed for the low/hi parts of a type
1212 /// which is split (or expanded) into two not necessarily identical pieces.
1213 std::pair<EVT, EVT> GetSplitDestVTs(const EVT &VT) const;
1215 /// Split the vector with EXTRACT_SUBVECTOR using the provides
1216 /// VTs and return the low/high part.
1217 std::pair<SDValue, SDValue> SplitVector(const SDValue &N, const SDLoc &DL,
1218 const EVT &LoVT, const EVT &HiVT);
1220 /// Split the vector with EXTRACT_SUBVECTOR and return the low/high part.
1221 std::pair<SDValue, SDValue> SplitVector(const SDValue &N, const SDLoc &DL) {
1223 std::tie(LoVT, HiVT) = GetSplitDestVTs(N.getValueType());
1224 return SplitVector(N, DL, LoVT, HiVT);
1227 /// Split the node's operand with EXTRACT_SUBVECTOR and
1228 /// return the low/high part.
1229 std::pair<SDValue, SDValue> SplitVectorOperand(const SDNode *N, unsigned OpNo)
1231 return SplitVector(N->getOperand(OpNo), SDLoc(N));
1234 /// Append the extracted elements from Start to Count out of the vector Op
1235 /// in Args. If Count is 0, all of the elements will be extracted.
1236 void ExtractVectorElements(SDValue Op, SmallVectorImpl<SDValue> &Args,
1237 unsigned Start = 0, unsigned Count = 0);
1239 unsigned getEVTAlignment(EVT MemoryVT) const;
1242 void InsertNode(SDNode *N);
1243 bool RemoveNodeFromCSEMaps(SDNode *N);
1244 void AddModifiedNodeToCSEMaps(SDNode *N);
1245 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos);
1246 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2,
1248 SDNode *FindModifiedNodeSlot(SDNode *N, ArrayRef<SDValue> Ops,
1250 SDNode *UpdadeSDLocOnMergedSDNode(SDNode *N, SDLoc loc);
1252 void DeleteNodeNotInCSEMaps(SDNode *N);
1253 void DeallocateNode(SDNode *N);
1255 void allnodes_clear();
1257 BinarySDNode *GetBinarySDNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
1258 SDValue N1, SDValue N2,
1259 const SDNodeFlags *Flags = nullptr);
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. This
1263 /// overload is for nodes other than Constant or ConstantFP, use the other one
1265 SDNode *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos);
1267 /// Look up the node specified by ID in CSEMap. If it exists, return it. If
1268 /// not, return the insertion token that will make insertion faster. Performs
1269 /// additional processing for constant nodes.
1270 SDNode *FindNodeOrInsertPos(const FoldingSetNodeID &ID, DebugLoc DL,
1273 /// List of non-single value types.
1274 FoldingSet<SDVTListNode> VTListMap;
1276 /// Maps to auto-CSE operations.
1277 std::vector<CondCodeSDNode*> CondCodeNodes;
1279 std::vector<SDNode*> ValueTypeNodes;
1280 std::map<EVT, SDNode*, EVT::compareRawBits> ExtendedValueTypeNodes;
1281 StringMap<SDNode*> ExternalSymbols;
1283 std::map<std::pair<std::string, unsigned char>,SDNode*> TargetExternalSymbols;
1284 DenseMap<MCSymbol *, SDNode *> MCSymbols;
1287 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
1288 typedef SelectionDAG::allnodes_iterator nodes_iterator;
1289 static nodes_iterator nodes_begin(SelectionDAG *G) {
1290 return G->allnodes_begin();
1292 static nodes_iterator nodes_end(SelectionDAG *G) {
1293 return G->allnodes_end();
1297 } // end namespace llvm