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 iterator_range<allnodes_iterator> allnodes() {
327 return iterator_range<allnodes_iterator>(allnodes_begin(), allnodes_end());
329 iterator_range<allnodes_const_iterator> allnodes() const {
330 return iterator_range<allnodes_const_iterator>(allnodes_begin(),
334 /// Return the root tag of the SelectionDAG.
335 const SDValue &getRoot() const { return Root; }
337 /// Return the token chain corresponding to the entry of the function.
338 SDValue getEntryNode() const {
339 return SDValue(const_cast<SDNode *>(&EntryNode), 0);
342 /// Set the current root tag of the SelectionDAG.
344 const SDValue &setRoot(SDValue N) {
345 assert((!N.getNode() || N.getValueType() == MVT::Other) &&
346 "DAG root value is not a chain!");
348 checkForCycles(N.getNode(), this);
351 checkForCycles(this);
355 /// This iterates over the nodes in the SelectionDAG, folding
356 /// certain types of nodes together, or eliminating superfluous nodes. The
357 /// Level argument controls whether Combine is allowed to produce nodes and
358 /// types that are illegal on the target.
359 void Combine(CombineLevel Level, AliasAnalysis &AA,
360 CodeGenOpt::Level OptLevel);
362 /// This transforms the SelectionDAG into a SelectionDAG that
363 /// only uses types natively supported by the target.
364 /// Returns "true" if it made any changes.
366 /// Note that this is an involved process that may invalidate pointers into
368 bool LegalizeTypes();
370 /// This transforms the SelectionDAG into a SelectionDAG that is
371 /// compatible with the target instruction selector, as indicated by the
372 /// TargetLowering object.
374 /// Note that this is an involved process that may invalidate pointers into
378 /// \brief Transforms a SelectionDAG node and any operands to it into a node
379 /// that is compatible with the target instruction selector, as indicated by
380 /// the TargetLowering object.
382 /// \returns true if \c N is a valid, legal node after calling this.
384 /// This essentially runs a single recursive walk of the \c Legalize process
385 /// over the given node (and its operands). This can be used to incrementally
386 /// legalize the DAG. All of the nodes which are directly replaced,
387 /// potentially including N, are added to the output parameter \c
388 /// UpdatedNodes so that the delta to the DAG can be understood by the
391 /// When this returns false, N has been legalized in a way that make the
392 /// pointer passed in no longer valid. It may have even been deleted from the
393 /// DAG, and so it shouldn't be used further. When this returns true, the
394 /// N passed in is a legal node, and can be immediately processed as such.
395 /// This may still have done some work on the DAG, and will still populate
396 /// UpdatedNodes with any new nodes replacing those originally in the DAG.
397 bool LegalizeOp(SDNode *N, SmallSetVector<SDNode *, 16> &UpdatedNodes);
399 /// This transforms the SelectionDAG into a SelectionDAG
400 /// that only uses vector math operations supported by the target. This is
401 /// necessary as a separate step from Legalize because unrolling a vector
402 /// operation can introduce illegal types, which requires running
403 /// LegalizeTypes again.
405 /// This returns true if it made any changes; in that case, LegalizeTypes
406 /// is called again before Legalize.
408 /// Note that this is an involved process that may invalidate pointers into
410 bool LegalizeVectors();
412 /// This method deletes all unreachable nodes in the SelectionDAG.
413 void RemoveDeadNodes();
415 /// Remove the specified node from the system. This node must
416 /// have no referrers.
417 void DeleteNode(SDNode *N);
419 /// Return an SDVTList that represents the list of values specified.
420 SDVTList getVTList(EVT VT);
421 SDVTList getVTList(EVT VT1, EVT VT2);
422 SDVTList getVTList(EVT VT1, EVT VT2, EVT VT3);
423 SDVTList getVTList(EVT VT1, EVT VT2, EVT VT3, EVT VT4);
424 SDVTList getVTList(ArrayRef<EVT> VTs);
426 //===--------------------------------------------------------------------===//
427 // Node creation methods.
429 SDValue getConstant(uint64_t Val, SDLoc DL, EVT VT, bool isTarget = false,
430 bool isOpaque = false);
431 SDValue getConstant(const APInt &Val, SDLoc DL, EVT VT, bool isTarget = false,
432 bool isOpaque = false);
433 SDValue getConstant(const ConstantInt &Val, SDLoc DL, EVT VT,
434 bool isTarget = false, bool isOpaque = false);
435 SDValue getIntPtrConstant(uint64_t Val, SDLoc DL, bool isTarget = false);
436 SDValue getTargetConstant(uint64_t Val, SDLoc DL, EVT VT,
437 bool isOpaque = false) {
438 return getConstant(Val, DL, VT, true, isOpaque);
440 SDValue getTargetConstant(const APInt &Val, SDLoc DL, EVT VT,
441 bool isOpaque = false) {
442 return getConstant(Val, DL, VT, true, isOpaque);
444 SDValue getTargetConstant(const ConstantInt &Val, SDLoc DL, EVT VT,
445 bool isOpaque = false) {
446 return getConstant(Val, DL, VT, true, isOpaque);
448 // The forms below that take a double should only be used for simple
449 // constants that can be exactly represented in VT. No checks are made.
450 SDValue getConstantFP(double Val, SDLoc DL, EVT VT, bool isTarget = false);
451 SDValue getConstantFP(const APFloat& Val, SDLoc DL, EVT VT,
452 bool isTarget = false);
453 SDValue getConstantFP(const ConstantFP &CF, SDLoc DL, EVT VT,
454 bool isTarget = false);
455 SDValue getTargetConstantFP(double Val, SDLoc DL, EVT VT) {
456 return getConstantFP(Val, DL, VT, true);
458 SDValue getTargetConstantFP(const APFloat& Val, SDLoc DL, EVT VT) {
459 return getConstantFP(Val, DL, VT, true);
461 SDValue getTargetConstantFP(const ConstantFP &Val, SDLoc DL, EVT VT) {
462 return getConstantFP(Val, DL, VT, true);
464 SDValue getGlobalAddress(const GlobalValue *GV, SDLoc DL, EVT VT,
465 int64_t offset = 0, bool isTargetGA = false,
466 unsigned char TargetFlags = 0);
467 SDValue getTargetGlobalAddress(const GlobalValue *GV, SDLoc DL, EVT VT,
469 unsigned char TargetFlags = 0) {
470 return getGlobalAddress(GV, DL, VT, offset, true, TargetFlags);
472 SDValue getFrameIndex(int FI, EVT VT, bool isTarget = false);
473 SDValue getTargetFrameIndex(int FI, EVT VT) {
474 return getFrameIndex(FI, VT, true);
476 SDValue getJumpTable(int JTI, EVT VT, bool isTarget = false,
477 unsigned char TargetFlags = 0);
478 SDValue getTargetJumpTable(int JTI, EVT VT, unsigned char TargetFlags = 0) {
479 return getJumpTable(JTI, VT, true, TargetFlags);
481 SDValue getConstantPool(const Constant *C, EVT VT,
482 unsigned Align = 0, int Offs = 0, bool isT=false,
483 unsigned char TargetFlags = 0);
484 SDValue getTargetConstantPool(const Constant *C, EVT VT,
485 unsigned Align = 0, int Offset = 0,
486 unsigned char TargetFlags = 0) {
487 return getConstantPool(C, VT, Align, Offset, true, TargetFlags);
489 SDValue getConstantPool(MachineConstantPoolValue *C, EVT VT,
490 unsigned Align = 0, int Offs = 0, bool isT=false,
491 unsigned char TargetFlags = 0);
492 SDValue getTargetConstantPool(MachineConstantPoolValue *C,
493 EVT VT, unsigned Align = 0,
494 int Offset = 0, unsigned char TargetFlags=0) {
495 return getConstantPool(C, VT, Align, Offset, true, TargetFlags);
497 SDValue getTargetIndex(int Index, EVT VT, int64_t Offset = 0,
498 unsigned char TargetFlags = 0);
499 // When generating a branch to a BB, we don't in general know enough
500 // to provide debug info for the BB at that time, so keep this one around.
501 SDValue getBasicBlock(MachineBasicBlock *MBB);
502 SDValue getBasicBlock(MachineBasicBlock *MBB, SDLoc dl);
503 SDValue getExternalSymbol(const char *Sym, EVT VT);
504 SDValue getExternalSymbol(const char *Sym, SDLoc dl, EVT VT);
505 SDValue getTargetExternalSymbol(const char *Sym, EVT VT,
506 unsigned char TargetFlags = 0);
507 SDValue getMCSymbol(MCSymbol *Sym, EVT VT);
509 SDValue getValueType(EVT);
510 SDValue getRegister(unsigned Reg, EVT VT);
511 SDValue getRegisterMask(const uint32_t *RegMask);
512 SDValue getEHLabel(SDLoc dl, SDValue Root, MCSymbol *Label);
513 SDValue getBlockAddress(const BlockAddress *BA, EVT VT,
514 int64_t Offset = 0, bool isTarget = false,
515 unsigned char TargetFlags = 0);
516 SDValue getTargetBlockAddress(const BlockAddress *BA, EVT VT,
518 unsigned char TargetFlags = 0) {
519 return getBlockAddress(BA, VT, Offset, true, TargetFlags);
522 SDValue getCopyToReg(SDValue Chain, SDLoc dl, unsigned Reg, SDValue N) {
523 return getNode(ISD::CopyToReg, dl, MVT::Other, Chain,
524 getRegister(Reg, N.getValueType()), N);
527 // This version of the getCopyToReg method takes an extra operand, which
528 // indicates that there is potentially an incoming glue value (if Glue is not
529 // null) and that there should be a glue result.
530 SDValue getCopyToReg(SDValue Chain, SDLoc dl, unsigned Reg, SDValue N,
532 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
533 SDValue Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Glue };
534 return getNode(ISD::CopyToReg, dl, VTs,
535 ArrayRef<SDValue>(Ops, Glue.getNode() ? 4 : 3));
538 // Similar to last getCopyToReg() except parameter Reg is a SDValue
539 SDValue getCopyToReg(SDValue Chain, SDLoc dl, SDValue Reg, SDValue N,
541 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
542 SDValue Ops[] = { Chain, Reg, N, Glue };
543 return getNode(ISD::CopyToReg, dl, VTs,
544 ArrayRef<SDValue>(Ops, Glue.getNode() ? 4 : 3));
547 SDValue getCopyFromReg(SDValue Chain, SDLoc dl, unsigned Reg, EVT VT) {
548 SDVTList VTs = getVTList(VT, MVT::Other);
549 SDValue Ops[] = { Chain, getRegister(Reg, VT) };
550 return getNode(ISD::CopyFromReg, dl, VTs, Ops);
553 // This version of the getCopyFromReg method takes an extra operand, which
554 // indicates that there is potentially an incoming glue value (if Glue is not
555 // null) and that there should be a glue result.
556 SDValue getCopyFromReg(SDValue Chain, SDLoc dl, unsigned Reg, EVT VT,
558 SDVTList VTs = getVTList(VT, MVT::Other, MVT::Glue);
559 SDValue Ops[] = { Chain, getRegister(Reg, VT), Glue };
560 return getNode(ISD::CopyFromReg, dl, VTs,
561 ArrayRef<SDValue>(Ops, Glue.getNode() ? 3 : 2));
564 SDValue getCondCode(ISD::CondCode Cond);
566 /// Returns the ConvertRndSat Note: Avoid using this node because it may
567 /// disappear in the future and most targets don't support it.
568 SDValue getConvertRndSat(EVT VT, SDLoc dl, SDValue Val, SDValue DTy,
570 SDValue Rnd, SDValue Sat, ISD::CvtCode Code);
572 /// Return an ISD::VECTOR_SHUFFLE node. The number of elements in VT,
573 /// which must be a vector type, must match the number of mask elements
574 /// NumElts. An integer mask element equal to -1 is treated as undefined.
575 SDValue getVectorShuffle(EVT VT, SDLoc dl, SDValue N1, SDValue N2,
576 const int *MaskElts);
577 SDValue getVectorShuffle(EVT VT, SDLoc dl, SDValue N1, SDValue N2,
578 ArrayRef<int> MaskElts) {
579 assert(VT.getVectorNumElements() == MaskElts.size() &&
580 "Must have the same number of vector elements as mask elements!");
581 return getVectorShuffle(VT, dl, N1, N2, MaskElts.data());
584 /// \brief Returns an ISD::VECTOR_SHUFFLE node semantically equivalent to
585 /// the shuffle node in input but with swapped operands.
587 /// Example: shuffle A, B, <0,5,2,7> -> shuffle B, A, <4,1,6,3>
588 SDValue getCommutedVectorShuffle(const ShuffleVectorSDNode &SV);
590 /// Convert Op, which must be of integer type, to the
591 /// integer type VT, by either any-extending or truncating it.
592 SDValue getAnyExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
594 /// Convert Op, which must be of integer type, to the
595 /// integer type VT, by either sign-extending or truncating it.
596 SDValue getSExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
598 /// Convert Op, which must be of integer type, to the
599 /// integer type VT, by either zero-extending or truncating it.
600 SDValue getZExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
602 /// Return the expression required to zero extend the Op
603 /// value assuming it was the smaller SrcTy value.
604 SDValue getZeroExtendInReg(SDValue Op, SDLoc DL, EVT SrcTy);
606 /// Return an operation which will any-extend the low lanes of the operand
607 /// into the specified vector type. For example,
608 /// this can convert a v16i8 into a v4i32 by any-extending the low four
609 /// lanes of the operand from i8 to i32.
610 SDValue getAnyExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
612 /// Return an operation which will sign extend the low lanes of the operand
613 /// into the specified vector type. For example,
614 /// this can convert a v16i8 into a v4i32 by sign extending the low four
615 /// lanes of the operand from i8 to i32.
616 SDValue getSignExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
618 /// Return an operation which will zero extend the low lanes of the operand
619 /// into the specified vector type. For example,
620 /// this can convert a v16i8 into a v4i32 by zero extending the low four
621 /// lanes of the operand from i8 to i32.
622 SDValue getZeroExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
624 /// Convert Op, which must be of integer type, to the integer type VT,
625 /// by using an extension appropriate for the target's
626 /// BooleanContent for type OpVT or truncating it.
627 SDValue getBoolExtOrTrunc(SDValue Op, SDLoc SL, EVT VT, EVT OpVT);
629 /// Create a bitwise NOT operation as (XOR Val, -1).
630 SDValue getNOT(SDLoc DL, SDValue Val, EVT VT);
632 /// \brief Create a logical NOT operation as (XOR Val, BooleanOne).
633 SDValue getLogicalNOT(SDLoc DL, SDValue Val, EVT VT);
635 /// Return a new CALLSEQ_START node, which always must have a glue result
636 /// (to ensure it's not CSE'd). CALLSEQ_START does not have a useful SDLoc.
637 SDValue getCALLSEQ_START(SDValue Chain, SDValue Op, SDLoc DL) {
638 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
639 SDValue Ops[] = { Chain, Op };
640 return getNode(ISD::CALLSEQ_START, DL, VTs, Ops);
643 /// Return a new CALLSEQ_END node, which always must have a
644 /// glue result (to ensure it's not CSE'd).
645 /// CALLSEQ_END does not have a useful SDLoc.
646 SDValue getCALLSEQ_END(SDValue Chain, SDValue Op1, SDValue Op2,
647 SDValue InGlue, SDLoc DL) {
648 SDVTList NodeTys = getVTList(MVT::Other, MVT::Glue);
649 SmallVector<SDValue, 4> Ops;
650 Ops.push_back(Chain);
653 if (InGlue.getNode())
654 Ops.push_back(InGlue);
655 return getNode(ISD::CALLSEQ_END, DL, NodeTys, Ops);
658 /// Return an UNDEF node. UNDEF does not have a useful SDLoc.
659 SDValue getUNDEF(EVT VT) {
660 return getNode(ISD::UNDEF, SDLoc(), VT);
663 /// Return a GLOBAL_OFFSET_TABLE node. This does not have a useful SDLoc.
664 SDValue getGLOBAL_OFFSET_TABLE(EVT VT) {
665 return getNode(ISD::GLOBAL_OFFSET_TABLE, SDLoc(), VT);
668 /// Gets or creates the specified node.
670 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT,
671 ArrayRef<SDUse> Ops);
672 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT,
673 ArrayRef<SDValue> Ops);
674 SDValue getNode(unsigned Opcode, SDLoc DL, ArrayRef<EVT> ResultTys,
675 ArrayRef<SDValue> Ops);
676 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
677 ArrayRef<SDValue> Ops);
679 // Specialize based on number of operands.
680 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT);
681 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N);
682 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
683 const SDNodeFlags *Flags = nullptr);
684 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
686 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
687 SDValue N3, SDValue N4);
688 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
689 SDValue N3, SDValue N4, SDValue N5);
691 // Specialize again based on number of operands for nodes with a VTList
692 // rather than a single VT.
693 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs);
694 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N);
695 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N1,
697 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N1,
698 SDValue N2, SDValue N3);
699 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N1,
700 SDValue N2, SDValue N3, SDValue N4);
701 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N1,
702 SDValue N2, SDValue N3, SDValue N4, SDValue N5);
704 /// Compute a TokenFactor to force all the incoming stack arguments to be
705 /// loaded from the stack. This is used in tail call lowering to protect
706 /// stack arguments from being clobbered.
707 SDValue getStackArgumentTokenFactor(SDValue Chain);
709 SDValue getMemcpy(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
710 SDValue Size, unsigned Align, bool isVol, bool AlwaysInline,
711 bool isTailCall, MachinePointerInfo DstPtrInfo,
712 MachinePointerInfo SrcPtrInfo);
714 SDValue getMemmove(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
715 SDValue Size, unsigned Align, bool isVol, bool isTailCall,
716 MachinePointerInfo DstPtrInfo,
717 MachinePointerInfo SrcPtrInfo);
719 SDValue getMemset(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
720 SDValue Size, unsigned Align, bool isVol, bool isTailCall,
721 MachinePointerInfo DstPtrInfo);
723 /// Helper function to make it easier to build SetCC's if you just
724 /// have an ISD::CondCode instead of an SDValue.
726 SDValue getSetCC(SDLoc DL, EVT VT, SDValue LHS, SDValue RHS,
727 ISD::CondCode Cond) {
728 assert(LHS.getValueType().isVector() == RHS.getValueType().isVector() &&
729 "Cannot compare scalars to vectors");
730 assert(LHS.getValueType().isVector() == VT.isVector() &&
731 "Cannot compare scalars to vectors");
732 assert(Cond != ISD::SETCC_INVALID &&
733 "Cannot create a setCC of an invalid node.");
734 return getNode(ISD::SETCC, DL, VT, LHS, RHS, getCondCode(Cond));
737 /// Helper function to make it easier to build Select's if you just
738 /// have operands and don't want to check for vector.
739 SDValue getSelect(SDLoc DL, EVT VT, SDValue Cond,
740 SDValue LHS, SDValue RHS) {
741 assert(LHS.getValueType() == RHS.getValueType() &&
742 "Cannot use select on differing types");
743 assert(VT.isVector() == LHS.getValueType().isVector() &&
744 "Cannot mix vectors and scalars");
745 return getNode(Cond.getValueType().isVector() ? ISD::VSELECT : ISD::SELECT, DL, VT,
749 /// Helper function to make it easier to build SelectCC's if you
750 /// just have an ISD::CondCode instead of an SDValue.
752 SDValue getSelectCC(SDLoc DL, SDValue LHS, SDValue RHS,
753 SDValue True, SDValue False, ISD::CondCode Cond) {
754 return getNode(ISD::SELECT_CC, DL, True.getValueType(),
755 LHS, RHS, True, False, getCondCode(Cond));
758 /// VAArg produces a result and token chain, and takes a pointer
759 /// and a source value as input.
760 SDValue getVAArg(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
761 SDValue SV, unsigned Align);
763 /// Gets a node for an atomic cmpxchg op. There are two
764 /// valid Opcodes. ISD::ATOMIC_CMO_SWAP produces the value loaded and a
765 /// chain result. ISD::ATOMIC_CMP_SWAP_WITH_SUCCESS produces the value loaded,
766 /// a success flag (initially i1), and a chain.
767 SDValue getAtomicCmpSwap(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTs,
768 SDValue Chain, SDValue Ptr, SDValue Cmp, SDValue Swp,
769 MachinePointerInfo PtrInfo, unsigned Alignment,
770 AtomicOrdering SuccessOrdering,
771 AtomicOrdering FailureOrdering,
772 SynchronizationScope SynchScope);
773 SDValue getAtomicCmpSwap(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTs,
774 SDValue Chain, SDValue Ptr, SDValue Cmp, SDValue Swp,
775 MachineMemOperand *MMO,
776 AtomicOrdering SuccessOrdering,
777 AtomicOrdering FailureOrdering,
778 SynchronizationScope SynchScope);
780 /// Gets a node for an atomic op, produces result (if relevant)
781 /// and chain and takes 2 operands.
782 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDValue Chain,
783 SDValue Ptr, SDValue Val, const Value *PtrVal,
784 unsigned Alignment, AtomicOrdering Ordering,
785 SynchronizationScope SynchScope);
786 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDValue Chain,
787 SDValue Ptr, SDValue Val, MachineMemOperand *MMO,
788 AtomicOrdering Ordering,
789 SynchronizationScope SynchScope);
791 /// Gets a node for an atomic op, produces result and chain and
793 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, EVT VT,
794 SDValue Chain, SDValue Ptr, MachineMemOperand *MMO,
795 AtomicOrdering Ordering,
796 SynchronizationScope SynchScope);
798 /// Gets a node for an atomic op, produces result and chain and takes N
800 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTList,
801 ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
802 AtomicOrdering SuccessOrdering,
803 AtomicOrdering FailureOrdering,
804 SynchronizationScope SynchScope);
805 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTList,
806 ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
807 AtomicOrdering Ordering, SynchronizationScope SynchScope);
809 /// Creates a MemIntrinsicNode that may produce a
810 /// result and takes a list of operands. Opcode may be INTRINSIC_VOID,
811 /// INTRINSIC_W_CHAIN, or a target-specific opcode with a value not
812 /// less than FIRST_TARGET_MEMORY_OPCODE.
813 SDValue getMemIntrinsicNode(unsigned Opcode, SDLoc dl, SDVTList VTList,
814 ArrayRef<SDValue> Ops,
815 EVT MemVT, MachinePointerInfo PtrInfo,
816 unsigned Align = 0, bool Vol = false,
817 bool ReadMem = true, bool WriteMem = true,
820 SDValue getMemIntrinsicNode(unsigned Opcode, SDLoc dl, SDVTList VTList,
821 ArrayRef<SDValue> Ops,
822 EVT MemVT, MachineMemOperand *MMO);
824 /// Create a MERGE_VALUES node from the given operands.
825 SDValue getMergeValues(ArrayRef<SDValue> Ops, SDLoc dl);
827 /// Loads are not normal binary operators: their result type is not
828 /// determined by their operands, and they produce a value AND a token chain.
830 SDValue getLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
831 MachinePointerInfo PtrInfo, bool isVolatile,
832 bool isNonTemporal, bool isInvariant, unsigned Alignment,
833 const AAMDNodes &AAInfo = AAMDNodes(),
834 const MDNode *Ranges = nullptr);
835 SDValue getLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
836 MachineMemOperand *MMO);
837 SDValue getExtLoad(ISD::LoadExtType ExtType, SDLoc dl, EVT VT,
838 SDValue Chain, SDValue Ptr, MachinePointerInfo PtrInfo,
839 EVT MemVT, bool isVolatile,
840 bool isNonTemporal, bool isInvariant, unsigned Alignment,
841 const AAMDNodes &AAInfo = AAMDNodes());
842 SDValue getExtLoad(ISD::LoadExtType ExtType, SDLoc dl, EVT VT,
843 SDValue Chain, SDValue Ptr, EVT MemVT,
844 MachineMemOperand *MMO);
845 SDValue getIndexedLoad(SDValue OrigLoad, SDLoc dl, SDValue Base,
846 SDValue Offset, ISD::MemIndexedMode AM);
847 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
849 SDValue Chain, SDValue Ptr, SDValue Offset,
850 MachinePointerInfo PtrInfo, EVT MemVT,
851 bool isVolatile, bool isNonTemporal, bool isInvariant,
852 unsigned Alignment, const AAMDNodes &AAInfo = AAMDNodes(),
853 const MDNode *Ranges = nullptr);
854 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
856 SDValue Chain, SDValue Ptr, SDValue Offset,
857 EVT MemVT, MachineMemOperand *MMO);
859 /// Helper function to build ISD::STORE nodes.
860 SDValue getStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
861 MachinePointerInfo PtrInfo, bool isVolatile,
862 bool isNonTemporal, unsigned Alignment,
863 const AAMDNodes &AAInfo = AAMDNodes());
864 SDValue getStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
865 MachineMemOperand *MMO);
866 SDValue getTruncStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
867 MachinePointerInfo PtrInfo, EVT TVT,
868 bool isNonTemporal, bool isVolatile,
870 const AAMDNodes &AAInfo = AAMDNodes());
871 SDValue getTruncStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
872 EVT TVT, MachineMemOperand *MMO);
873 SDValue getIndexedStore(SDValue OrigStoe, SDLoc dl, SDValue Base,
874 SDValue Offset, ISD::MemIndexedMode AM);
876 SDValue getMaskedLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
877 SDValue Mask, SDValue Src0, EVT MemVT,
878 MachineMemOperand *MMO, ISD::LoadExtType);
879 SDValue getMaskedStore(SDValue Chain, SDLoc dl, SDValue Val,
880 SDValue Ptr, SDValue Mask, EVT MemVT,
881 MachineMemOperand *MMO, bool IsTrunc);
882 SDValue getMaskedGather(SDVTList VTs, EVT VT, SDLoc dl,
883 ArrayRef<SDValue> Ops, MachineMemOperand *MMO);
884 SDValue getMaskedScatter(SDVTList VTs, EVT VT, SDLoc dl,
885 ArrayRef<SDValue> Ops, MachineMemOperand *MMO);
886 /// Construct a node to track a Value* through the backend.
887 SDValue getSrcValue(const Value *v);
889 /// Return an MDNodeSDNode which holds an MDNode.
890 SDValue getMDNode(const MDNode *MD);
892 /// Return a bitcast using the SDLoc of the value operand, and casting to the
893 /// provided type. Use getNode to set a custom SDLoc.
894 SDValue getBitcast(EVT VT, SDValue V);
896 /// Return an AddrSpaceCastSDNode.
897 SDValue getAddrSpaceCast(SDLoc dl, EVT VT, SDValue Ptr,
898 unsigned SrcAS, unsigned DestAS);
900 /// Return the specified value casted to
901 /// the target's desired shift amount type.
902 SDValue getShiftAmountOperand(EVT LHSTy, SDValue Op);
904 /// *Mutate* the specified node in-place to have the
905 /// specified operands. If the resultant node already exists in the DAG,
906 /// this does not modify the specified node, instead it returns the node that
907 /// already exists. If the resultant node does not exist in the DAG, the
908 /// input node is returned. As a degenerate case, if you specify the same
909 /// input operands as the node already has, the input node is returned.
910 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op);
911 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2);
912 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
914 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
915 SDValue Op3, SDValue Op4);
916 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
917 SDValue Op3, SDValue Op4, SDValue Op5);
918 SDNode *UpdateNodeOperands(SDNode *N, ArrayRef<SDValue> Ops);
920 /// These are used for target selectors to *mutate* the
921 /// specified node to have the specified return type, Target opcode, and
922 /// operands. Note that target opcodes are stored as
923 /// ~TargetOpcode in the node opcode field. The resultant node is returned.
924 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT);
925 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT, SDValue Op1);
926 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
927 SDValue Op1, SDValue Op2);
928 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
929 SDValue Op1, SDValue Op2, SDValue Op3);
930 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
931 ArrayRef<SDValue> Ops);
932 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1, EVT VT2);
933 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
934 EVT VT2, ArrayRef<SDValue> Ops);
935 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
936 EVT VT2, EVT VT3, ArrayRef<SDValue> Ops);
937 SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT1,
938 EVT VT2, EVT VT3, EVT VT4, ArrayRef<SDValue> Ops);
939 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
940 EVT VT2, SDValue Op1);
941 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
942 EVT VT2, SDValue Op1, SDValue Op2);
943 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
944 EVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
945 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
946 EVT VT2, EVT VT3, SDValue Op1, SDValue Op2, SDValue Op3);
947 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
948 ArrayRef<SDValue> Ops);
950 /// This *mutates* the specified node to have the specified
951 /// return type, opcode, and operands.
952 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
953 ArrayRef<SDValue> Ops);
955 /// These are used for target selectors to create a new node
956 /// with specified return type(s), MachineInstr opcode, and operands.
958 /// Note that getMachineNode returns the resultant node. If there is already
959 /// a node of the specified opcode and operands, it returns that node instead
960 /// of the current one.
961 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT);
962 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
964 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
965 SDValue Op1, SDValue Op2);
966 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
967 SDValue Op1, SDValue Op2, SDValue Op3);
968 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
969 ArrayRef<SDValue> Ops);
970 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2);
971 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
973 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
974 SDValue Op1, SDValue Op2);
975 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
976 SDValue Op1, SDValue Op2, SDValue Op3);
977 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
978 ArrayRef<SDValue> Ops);
979 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
980 EVT VT3, SDValue Op1, SDValue Op2);
981 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
982 EVT VT3, SDValue Op1, SDValue Op2,
984 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
985 EVT VT3, ArrayRef<SDValue> Ops);
986 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
987 EVT VT3, EVT VT4, ArrayRef<SDValue> Ops);
988 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl,
989 ArrayRef<EVT> ResultTys,
990 ArrayRef<SDValue> Ops);
991 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, SDVTList VTs,
992 ArrayRef<SDValue> Ops);
994 /// A convenience function for creating TargetInstrInfo::EXTRACT_SUBREG nodes.
995 SDValue getTargetExtractSubreg(int SRIdx, SDLoc DL, EVT VT,
998 /// A convenience function for creating TargetInstrInfo::INSERT_SUBREG nodes.
999 SDValue getTargetInsertSubreg(int SRIdx, SDLoc DL, EVT VT,
1000 SDValue Operand, SDValue Subreg);
1002 /// Get the specified node if it's already available, or else return NULL.
1003 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs, ArrayRef<SDValue> Ops,
1004 const SDNodeFlags *Flags = nullptr);
1006 /// Creates a SDDbgValue node.
1007 SDDbgValue *getDbgValue(MDNode *Var, MDNode *Expr, SDNode *N, unsigned R,
1008 bool IsIndirect, uint64_t Off, DebugLoc DL,
1012 SDDbgValue *getConstantDbgValue(MDNode *Var, MDNode *Expr, const Value *C,
1013 uint64_t Off, DebugLoc DL, unsigned O);
1016 SDDbgValue *getFrameIndexDbgValue(MDNode *Var, MDNode *Expr, unsigned FI,
1017 uint64_t Off, DebugLoc DL, unsigned O);
1019 /// Remove the specified node from the system. If any of its
1020 /// operands then becomes dead, remove them as well. Inform UpdateListener
1021 /// for each node deleted.
1022 void RemoveDeadNode(SDNode *N);
1024 /// This method deletes the unreachable nodes in the
1025 /// given list, and any nodes that become unreachable as a result.
1026 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes);
1028 /// Modify anything using 'From' to use 'To' instead.
1029 /// This can cause recursive merging of nodes in the DAG. Use the first
1030 /// version if 'From' is known to have a single result, use the second
1031 /// if you have two nodes with identical results (or if 'To' has a superset
1032 /// of the results of 'From'), use the third otherwise.
1034 /// These methods all take an optional UpdateListener, which (if not null) is
1035 /// informed about nodes that are deleted and modified due to recursive
1036 /// changes in the dag.
1038 /// These functions only replace all existing uses. It's possible that as
1039 /// these replacements are being performed, CSE may cause the From node
1040 /// to be given new uses. These new uses of From are left in place, and
1041 /// not automatically transferred to To.
1043 void ReplaceAllUsesWith(SDValue From, SDValue Op);
1044 void ReplaceAllUsesWith(SDNode *From, SDNode *To);
1045 void ReplaceAllUsesWith(SDNode *From, const SDValue *To);
1047 /// Replace any uses of From with To, leaving
1048 /// uses of other values produced by From.Val alone.
1049 void ReplaceAllUsesOfValueWith(SDValue From, SDValue To);
1051 /// Like ReplaceAllUsesOfValueWith, but for multiple values at once.
1052 /// This correctly handles the case where
1053 /// there is an overlap between the From values and the To values.
1054 void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To,
1057 /// Topological-sort the AllNodes list and a
1058 /// assign a unique node id for each node in the DAG based on their
1059 /// topological order. Returns the number of nodes.
1060 unsigned AssignTopologicalOrder();
1062 /// Move node N in the AllNodes list to be immediately
1063 /// before the given iterator Position. This may be used to update the
1064 /// topological ordering when the list of nodes is modified.
1065 void RepositionNode(allnodes_iterator Position, SDNode *N) {
1066 AllNodes.insert(Position, AllNodes.remove(N));
1069 /// Returns true if the opcode is a commutative binary operation.
1070 static bool isCommutativeBinOp(unsigned Opcode) {
1071 // FIXME: This should get its info from the td file, so that we can include
1078 case ISD::SMUL_LOHI:
1079 case ISD::UMUL_LOHI:
1094 default: return false;
1098 /// Returns an APFloat semantics tag appropriate for the given type. If VT is
1099 /// a vector type, the element semantics are returned.
1100 static const fltSemantics &EVTToAPFloatSemantics(EVT VT) {
1101 switch (VT.getScalarType().getSimpleVT().SimpleTy) {
1102 default: llvm_unreachable("Unknown FP format");
1103 case MVT::f16: return APFloat::IEEEhalf;
1104 case MVT::f32: return APFloat::IEEEsingle;
1105 case MVT::f64: return APFloat::IEEEdouble;
1106 case MVT::f80: return APFloat::x87DoubleExtended;
1107 case MVT::f128: return APFloat::IEEEquad;
1108 case MVT::ppcf128: return APFloat::PPCDoubleDouble;
1112 /// Add a dbg_value SDNode. If SD is non-null that means the
1113 /// value is produced by SD.
1114 void AddDbgValue(SDDbgValue *DB, SDNode *SD, bool isParameter);
1116 /// Get the debug values which reference the given SDNode.
1117 ArrayRef<SDDbgValue*> GetDbgValues(const SDNode* SD) {
1118 return DbgInfo->getSDDbgValues(SD);
1121 /// Transfer SDDbgValues.
1122 void TransferDbgValues(SDValue From, SDValue To);
1124 /// Return true if there are any SDDbgValue nodes associated
1125 /// with this SelectionDAG.
1126 bool hasDebugValues() const { return !DbgInfo->empty(); }
1128 SDDbgInfo::DbgIterator DbgBegin() { return DbgInfo->DbgBegin(); }
1129 SDDbgInfo::DbgIterator DbgEnd() { return DbgInfo->DbgEnd(); }
1130 SDDbgInfo::DbgIterator ByvalParmDbgBegin() {
1131 return DbgInfo->ByvalParmDbgBegin();
1133 SDDbgInfo::DbgIterator ByvalParmDbgEnd() {
1134 return DbgInfo->ByvalParmDbgEnd();
1139 /// Create a stack temporary, suitable for holding the
1140 /// specified value type. If minAlign is specified, the slot size will have
1141 /// at least that alignment.
1142 SDValue CreateStackTemporary(EVT VT, unsigned minAlign = 1);
1144 /// Create a stack temporary suitable for holding
1145 /// either of the specified value types.
1146 SDValue CreateStackTemporary(EVT VT1, EVT VT2);
1148 SDValue FoldConstantArithmetic(unsigned Opcode, SDLoc DL, EVT VT,
1149 SDNode *Cst1, SDNode *Cst2);
1151 SDValue FoldConstantArithmetic(unsigned Opcode, SDLoc DL, EVT VT,
1152 const ConstantSDNode *Cst1,
1153 const ConstantSDNode *Cst2);
1155 /// Constant fold a setcc to true or false.
1156 SDValue FoldSetCC(EVT VT, SDValue N1,
1157 SDValue N2, ISD::CondCode Cond, SDLoc dl);
1159 /// Return true if the sign bit of Op is known to be zero.
1160 /// We use this predicate to simplify operations downstream.
1161 bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const;
1163 /// Return true if 'Op & Mask' is known to be zero. We
1164 /// use this predicate to simplify operations downstream. Op and Mask are
1165 /// known to be the same type.
1166 bool MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth = 0)
1169 /// Determine which bits of Op are known to be either zero or one and return
1170 /// them in the KnownZero/KnownOne bitsets. Targets can implement the
1171 /// computeKnownBitsForTargetNode method in the TargetLowering class to allow
1172 /// target nodes to be understood.
1173 void computeKnownBits(SDValue Op, APInt &KnownZero, APInt &KnownOne,
1174 unsigned Depth = 0) const;
1176 /// Return the number of times the sign bit of the
1177 /// register is replicated into the other bits. We know that at least 1 bit
1178 /// is always equal to the sign bit (itself), but other cases can give us
1179 /// information. For example, immediately after an "SRA X, 2", we know that
1180 /// the top 3 bits are all equal to each other, so we return 3. Targets can
1181 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
1182 /// class to allow target nodes to be understood.
1183 unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const;
1185 /// Return true if the specified operand is an
1186 /// ISD::ADD with a ConstantSDNode on the right-hand side, or if it is an
1187 /// ISD::OR with a ConstantSDNode that is guaranteed to have the same
1188 /// semantics as an ADD. This handles the equivalence:
1189 /// X|Cst == X+Cst iff X&Cst = 0.
1190 bool isBaseWithConstantOffset(SDValue Op) const;
1192 /// Test whether the given SDValue is known to never be NaN.
1193 bool isKnownNeverNaN(SDValue Op) const;
1195 /// Test whether the given SDValue is known to never be
1196 /// positive or negative Zero.
1197 bool isKnownNeverZero(SDValue Op) const;
1199 /// Test whether two SDValues are known to compare equal. This
1200 /// is true if they are the same value, or if one is negative zero and the
1201 /// other positive zero.
1202 bool isEqualTo(SDValue A, SDValue B) const;
1204 /// Utility function used by legalize and lowering to
1205 /// "unroll" a vector operation by splitting out the scalars and operating
1206 /// on each element individually. If the ResNE is 0, fully unroll the vector
1207 /// op. If ResNE is less than the width of the vector op, unroll up to ResNE.
1208 /// If the ResNE is greater than the width of the vector op, unroll the
1209 /// vector op and fill the end of the resulting vector with UNDEFS.
1210 SDValue UnrollVectorOp(SDNode *N, unsigned ResNE = 0);
1212 /// Return true if LD is loading 'Bytes' bytes from a location that is 'Dist'
1213 /// units away from the location that the 'Base' load is loading from.
1214 bool isConsecutiveLoad(LoadSDNode *LD, LoadSDNode *Base,
1215 unsigned Bytes, int Dist) const;
1217 /// Infer alignment of a load / store address. Return 0 if
1218 /// it cannot be inferred.
1219 unsigned InferPtrAlignment(SDValue Ptr) const;
1221 /// Compute the VTs needed for the low/hi parts of a type
1222 /// which is split (or expanded) into two not necessarily identical pieces.
1223 std::pair<EVT, EVT> GetSplitDestVTs(const EVT &VT) const;
1225 /// Split the vector with EXTRACT_SUBVECTOR using the provides
1226 /// VTs and return the low/high part.
1227 std::pair<SDValue, SDValue> SplitVector(const SDValue &N, const SDLoc &DL,
1228 const EVT &LoVT, const EVT &HiVT);
1230 /// Split the vector with EXTRACT_SUBVECTOR and return the low/high part.
1231 std::pair<SDValue, SDValue> SplitVector(const SDValue &N, const SDLoc &DL) {
1233 std::tie(LoVT, HiVT) = GetSplitDestVTs(N.getValueType());
1234 return SplitVector(N, DL, LoVT, HiVT);
1237 /// Split the node's operand with EXTRACT_SUBVECTOR and
1238 /// return the low/high part.
1239 std::pair<SDValue, SDValue> SplitVectorOperand(const SDNode *N, unsigned OpNo)
1241 return SplitVector(N->getOperand(OpNo), SDLoc(N));
1244 /// Append the extracted elements from Start to Count out of the vector Op
1245 /// in Args. If Count is 0, all of the elements will be extracted.
1246 void ExtractVectorElements(SDValue Op, SmallVectorImpl<SDValue> &Args,
1247 unsigned Start = 0, unsigned Count = 0);
1249 unsigned getEVTAlignment(EVT MemoryVT) const;
1252 void InsertNode(SDNode *N);
1253 bool RemoveNodeFromCSEMaps(SDNode *N);
1254 void AddModifiedNodeToCSEMaps(SDNode *N);
1255 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos);
1256 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2,
1258 SDNode *FindModifiedNodeSlot(SDNode *N, ArrayRef<SDValue> Ops,
1260 SDNode *UpdadeSDLocOnMergedSDNode(SDNode *N, SDLoc loc);
1262 void DeleteNodeNotInCSEMaps(SDNode *N);
1263 void DeallocateNode(SDNode *N);
1265 void allnodes_clear();
1267 BinarySDNode *GetBinarySDNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
1268 SDValue N1, SDValue N2,
1269 const SDNodeFlags *Flags = nullptr);
1271 /// Look up the node specified by ID in CSEMap. If it exists, return it. If
1272 /// not, return the insertion token that will make insertion faster. This
1273 /// overload is for nodes other than Constant or ConstantFP, use the other one
1275 SDNode *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos);
1277 /// Look up the node specified by ID in CSEMap. If it exists, return it. If
1278 /// not, return the insertion token that will make insertion faster. Performs
1279 /// additional processing for constant nodes.
1280 SDNode *FindNodeOrInsertPos(const FoldingSetNodeID &ID, DebugLoc DL,
1283 /// List of non-single value types.
1284 FoldingSet<SDVTListNode> VTListMap;
1286 /// Maps to auto-CSE operations.
1287 std::vector<CondCodeSDNode*> CondCodeNodes;
1289 std::vector<SDNode*> ValueTypeNodes;
1290 std::map<EVT, SDNode*, EVT::compareRawBits> ExtendedValueTypeNodes;
1291 StringMap<SDNode*> ExternalSymbols;
1293 std::map<std::pair<std::string, unsigned char>,SDNode*> TargetExternalSymbols;
1294 DenseMap<MCSymbol *, SDNode *> MCSymbols;
1297 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
1298 typedef SelectionDAG::allnodes_iterator nodes_iterator;
1299 static nodes_iterator nodes_begin(SelectionDAG *G) {
1300 return G->allnodes_begin();
1302 static nodes_iterator nodes_end(SelectionDAG *G) {
1303 return G->allnodes_end();
1307 } // end namespace llvm