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 SmallVector<SDDbgValue*, 32> DbgValues;
116 SmallVector<SDDbgValue*, 32> ByvalParmDbgValues;
117 typedef DenseMap<const SDNode*, SmallVector<SDDbgValue*, 2> > DbgValMapType;
118 DbgValMapType DbgValMap;
120 void operator=(const SDDbgInfo&) = delete;
121 SDDbgInfo(const SDDbgInfo&) = delete;
125 void add(SDDbgValue *V, const SDNode *Node, bool isParameter) {
127 ByvalParmDbgValues.push_back(V);
128 } else DbgValues.push_back(V);
130 DbgValMap[Node].push_back(V);
133 /// \brief Invalidate all DbgValues attached to the node and remove
134 /// it from the Node-to-DbgValues map.
135 void erase(const SDNode *Node);
140 ByvalParmDbgValues.clear();
144 return DbgValues.empty() && ByvalParmDbgValues.empty();
147 ArrayRef<SDDbgValue*> getSDDbgValues(const SDNode *Node) {
148 DbgValMapType::iterator I = DbgValMap.find(Node);
149 if (I != DbgValMap.end())
151 return ArrayRef<SDDbgValue*>();
154 typedef SmallVectorImpl<SDDbgValue*>::iterator DbgIterator;
155 DbgIterator DbgBegin() { return DbgValues.begin(); }
156 DbgIterator DbgEnd() { return DbgValues.end(); }
157 DbgIterator ByvalParmDbgBegin() { return ByvalParmDbgValues.begin(); }
158 DbgIterator ByvalParmDbgEnd() { return ByvalParmDbgValues.end(); }
162 void checkForCycles(const SelectionDAG *DAG, bool force = false);
164 /// This is used to represent a portion of an LLVM function in a low-level
165 /// Data Dependence DAG representation suitable for instruction selection.
166 /// This DAG is constructed as the first step of instruction selection in order
167 /// to allow implementation of machine specific optimizations
168 /// and code simplifications.
170 /// The representation used by the SelectionDAG is a target-independent
171 /// representation, which has some similarities to the GCC RTL representation,
172 /// but is significantly more simple, powerful, and is a graph form instead of a
176 const TargetMachine &TM;
177 const TargetSelectionDAGInfo *TSI;
178 const TargetLowering *TLI;
180 LLVMContext *Context;
181 CodeGenOpt::Level OptLevel;
183 /// The starting token.
186 /// The root of the entire DAG.
189 /// A linked list of nodes in the current DAG.
190 ilist<SDNode> AllNodes;
192 /// The AllocatorType for allocating SDNodes. We use
193 /// pool allocation with recycling.
194 typedef RecyclingAllocator<BumpPtrAllocator, SDNode, sizeof(LargestSDNode),
195 AlignOf<MostAlignedSDNode>::Alignment>
198 /// Pool allocation for nodes.
199 NodeAllocatorType NodeAllocator;
201 /// This structure is used to memoize nodes, automatically performing
202 /// CSE with existing nodes when a duplicate is requested.
203 FoldingSet<SDNode> CSEMap;
205 /// Pool allocation for machine-opcode SDNode operands.
206 BumpPtrAllocator OperandAllocator;
208 /// Pool allocation for misc. objects that are created once per SelectionDAG.
209 BumpPtrAllocator Allocator;
211 /// Tracks dbg_value information through SDISel.
215 /// Clients of various APIs that cause global effects on
216 /// the DAG can optionally implement this interface. This allows the clients
217 /// to handle the various sorts of updates that happen.
219 /// A DAGUpdateListener automatically registers itself with DAG when it is
220 /// constructed, and removes itself when destroyed in RAII fashion.
221 struct DAGUpdateListener {
222 DAGUpdateListener *const Next;
225 explicit DAGUpdateListener(SelectionDAG &D)
226 : Next(D.UpdateListeners), DAG(D) {
227 DAG.UpdateListeners = this;
230 virtual ~DAGUpdateListener() {
231 assert(DAG.UpdateListeners == this &&
232 "DAGUpdateListeners must be destroyed in LIFO order");
233 DAG.UpdateListeners = Next;
236 /// The node N that was deleted and, if E is not null, an
237 /// equivalent node E that replaced it.
238 virtual void NodeDeleted(SDNode *N, SDNode *E);
240 /// The node N that was updated.
241 virtual void NodeUpdated(SDNode *N);
244 /// When true, additional steps are taken to
245 /// ensure that getConstant() and similar functions return DAG nodes that
246 /// have legal types. This is important after type legalization since
247 /// any illegally typed nodes generated after this point will not experience
248 /// type legalization.
249 bool NewNodesMustHaveLegalTypes;
252 /// DAGUpdateListener is a friend so it can manipulate the listener stack.
253 friend struct DAGUpdateListener;
255 /// Linked list of registered DAGUpdateListener instances.
256 /// This stack is maintained by DAGUpdateListener RAII.
257 DAGUpdateListener *UpdateListeners;
259 /// Implementation of setSubgraphColor.
260 /// Return whether we had to truncate the search.
261 bool setSubgraphColorHelper(SDNode *N, const char *Color,
262 DenseSet<SDNode *> &visited,
263 int level, bool &printed);
265 void operator=(const SelectionDAG&) = delete;
266 SelectionDAG(const SelectionDAG&) = delete;
269 explicit SelectionDAG(const TargetMachine &TM, llvm::CodeGenOpt::Level);
272 /// Prepare this SelectionDAG to process code in the given MachineFunction.
273 void init(MachineFunction &mf);
275 /// Clear state and free memory necessary to make this
276 /// SelectionDAG ready to process a new block.
279 MachineFunction &getMachineFunction() const { return *MF; }
280 const TargetMachine &getTarget() const { return TM; }
281 const TargetSubtargetInfo &getSubtarget() const { return MF->getSubtarget(); }
282 const TargetLowering &getTargetLoweringInfo() const { return *TLI; }
283 const TargetSelectionDAGInfo &getSelectionDAGInfo() const { return *TSI; }
284 LLVMContext *getContext() const {return Context; }
286 /// Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
287 void viewGraph(const std::string &Title);
291 std::map<const SDNode *, std::string> NodeGraphAttrs;
294 /// Clear all previously defined node graph attributes.
295 /// Intended to be used from a debugging tool (eg. gdb).
296 void clearGraphAttrs();
298 /// Set graph attributes for a node. (eg. "color=red".)
299 void setGraphAttrs(const SDNode *N, const char *Attrs);
301 /// Get graph attributes for a node. (eg. "color=red".)
302 /// Used from getNodeAttributes.
303 const std::string getGraphAttrs(const SDNode *N) const;
305 /// Convenience for setting node color attribute.
306 void setGraphColor(const SDNode *N, const char *Color);
308 /// Convenience for setting subgraph color attribute.
309 void setSubgraphColor(SDNode *N, const char *Color);
311 typedef ilist<SDNode>::const_iterator allnodes_const_iterator;
312 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
313 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
314 typedef ilist<SDNode>::iterator allnodes_iterator;
315 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
316 allnodes_iterator allnodes_end() { return AllNodes.end(); }
317 ilist<SDNode>::size_type allnodes_size() const {
318 return AllNodes.size();
321 /// Return the root tag of the SelectionDAG.
322 const SDValue &getRoot() const { return Root; }
324 /// Return the token chain corresponding to the entry of the function.
325 SDValue getEntryNode() const {
326 return SDValue(const_cast<SDNode *>(&EntryNode), 0);
329 /// Set the current root tag of the SelectionDAG.
331 const SDValue &setRoot(SDValue N) {
332 assert((!N.getNode() || N.getValueType() == MVT::Other) &&
333 "DAG root value is not a chain!");
335 checkForCycles(N.getNode(), this);
338 checkForCycles(this);
342 /// This iterates over the nodes in the SelectionDAG, folding
343 /// certain types of nodes together, or eliminating superfluous nodes. The
344 /// Level argument controls whether Combine is allowed to produce nodes and
345 /// types that are illegal on the target.
346 void Combine(CombineLevel Level, AliasAnalysis &AA,
347 CodeGenOpt::Level OptLevel);
349 /// This transforms the SelectionDAG into a SelectionDAG that
350 /// only uses types natively supported by the target.
351 /// Returns "true" if it made any changes.
353 /// Note that this is an involved process that may invalidate pointers into
355 bool LegalizeTypes();
357 /// This transforms the SelectionDAG into a SelectionDAG that is
358 /// compatible with the target instruction selector, as indicated by the
359 /// TargetLowering object.
361 /// Note that this is an involved process that may invalidate pointers into
365 /// \brief Transforms a SelectionDAG node and any operands to it into a node
366 /// that is compatible with the target instruction selector, as indicated by
367 /// the TargetLowering object.
369 /// \returns true if \c N is a valid, legal node after calling this.
371 /// This essentially runs a single recursive walk of the \c Legalize process
372 /// over the given node (and its operands). This can be used to incrementally
373 /// legalize the DAG. All of the nodes which are directly replaced,
374 /// potentially including N, are added to the output parameter \c
375 /// UpdatedNodes so that the delta to the DAG can be understood by the
378 /// When this returns false, N has been legalized in a way that make the
379 /// pointer passed in no longer valid. It may have even been deleted from the
380 /// DAG, and so it shouldn't be used further. When this returns true, the
381 /// N passed in is a legal node, and can be immediately processed as such.
382 /// This may still have done some work on the DAG, and will still populate
383 /// UpdatedNodes with any new nodes replacing those originally in the DAG.
384 bool LegalizeOp(SDNode *N, SmallSetVector<SDNode *, 16> &UpdatedNodes);
386 /// This transforms the SelectionDAG into a SelectionDAG
387 /// that only uses vector math operations supported by the target. This is
388 /// necessary as a separate step from Legalize because unrolling a vector
389 /// operation can introduce illegal types, which requires running
390 /// LegalizeTypes again.
392 /// This returns true if it made any changes; in that case, LegalizeTypes
393 /// is called again before Legalize.
395 /// Note that this is an involved process that may invalidate pointers into
397 bool LegalizeVectors();
399 /// This method deletes all unreachable nodes in the SelectionDAG.
400 void RemoveDeadNodes();
402 /// Remove the specified node from the system. This node must
403 /// have no referrers.
404 void DeleteNode(SDNode *N);
406 /// Return an SDVTList that represents the list of values specified.
407 SDVTList getVTList(EVT VT);
408 SDVTList getVTList(EVT VT1, EVT VT2);
409 SDVTList getVTList(EVT VT1, EVT VT2, EVT VT3);
410 SDVTList getVTList(EVT VT1, EVT VT2, EVT VT3, EVT VT4);
411 SDVTList getVTList(ArrayRef<EVT> VTs);
413 //===--------------------------------------------------------------------===//
414 // Node creation methods.
416 SDValue getConstant(uint64_t Val, EVT VT, bool isTarget = false,
417 bool isOpaque = false);
418 SDValue getConstant(const APInt &Val, EVT VT, bool isTarget = false,
419 bool isOpaque = false);
420 SDValue getConstant(const ConstantInt &Val, EVT VT, bool isTarget = false,
421 bool isOpaque = false);
422 SDValue getIntPtrConstant(uint64_t Val, bool isTarget = false);
423 SDValue getTargetConstant(uint64_t Val, EVT VT, bool isOpaque = false) {
424 return getConstant(Val, VT, true, isOpaque);
426 SDValue getTargetConstant(const APInt &Val, EVT VT, bool isOpaque = false) {
427 return getConstant(Val, VT, true, isOpaque);
429 SDValue getTargetConstant(const ConstantInt &Val, EVT VT,
430 bool isOpaque = false) {
431 return getConstant(Val, VT, true, isOpaque);
433 // The forms below that take a double should only be used for simple
434 // constants that can be exactly represented in VT. No checks are made.
435 SDValue getConstantFP(double Val, EVT VT, bool isTarget = false);
436 SDValue getConstantFP(const APFloat& Val, EVT VT, bool isTarget = false);
437 SDValue getConstantFP(const ConstantFP &CF, EVT VT, bool isTarget = false);
438 SDValue getTargetConstantFP(double Val, EVT VT) {
439 return getConstantFP(Val, VT, true);
441 SDValue getTargetConstantFP(const APFloat& Val, EVT VT) {
442 return getConstantFP(Val, VT, true);
444 SDValue getTargetConstantFP(const ConstantFP &Val, EVT VT) {
445 return getConstantFP(Val, VT, true);
447 SDValue getGlobalAddress(const GlobalValue *GV, SDLoc DL, EVT VT,
448 int64_t offset = 0, bool isTargetGA = false,
449 unsigned char TargetFlags = 0);
450 SDValue getTargetGlobalAddress(const GlobalValue *GV, SDLoc DL, EVT VT,
452 unsigned char TargetFlags = 0) {
453 return getGlobalAddress(GV, DL, VT, offset, true, TargetFlags);
455 SDValue getFrameIndex(int FI, EVT VT, bool isTarget = false);
456 SDValue getTargetFrameIndex(int FI, EVT VT) {
457 return getFrameIndex(FI, VT, true);
459 SDValue getJumpTable(int JTI, EVT VT, bool isTarget = false,
460 unsigned char TargetFlags = 0);
461 SDValue getTargetJumpTable(int JTI, EVT VT, unsigned char TargetFlags = 0) {
462 return getJumpTable(JTI, VT, true, TargetFlags);
464 SDValue getConstantPool(const Constant *C, EVT VT,
465 unsigned Align = 0, int Offs = 0, bool isT=false,
466 unsigned char TargetFlags = 0);
467 SDValue getTargetConstantPool(const Constant *C, EVT VT,
468 unsigned Align = 0, int Offset = 0,
469 unsigned char TargetFlags = 0) {
470 return getConstantPool(C, VT, Align, Offset, true, TargetFlags);
472 SDValue getConstantPool(MachineConstantPoolValue *C, EVT VT,
473 unsigned Align = 0, int Offs = 0, bool isT=false,
474 unsigned char TargetFlags = 0);
475 SDValue getTargetConstantPool(MachineConstantPoolValue *C,
476 EVT VT, unsigned Align = 0,
477 int Offset = 0, unsigned char TargetFlags=0) {
478 return getConstantPool(C, VT, Align, Offset, true, TargetFlags);
480 SDValue getTargetIndex(int Index, EVT VT, int64_t Offset = 0,
481 unsigned char TargetFlags = 0);
482 // When generating a branch to a BB, we don't in general know enough
483 // to provide debug info for the BB at that time, so keep this one around.
484 SDValue getBasicBlock(MachineBasicBlock *MBB);
485 SDValue getBasicBlock(MachineBasicBlock *MBB, SDLoc dl);
486 SDValue getExternalSymbol(const char *Sym, EVT VT);
487 SDValue getExternalSymbol(const char *Sym, SDLoc dl, EVT VT);
488 SDValue getTargetExternalSymbol(const char *Sym, EVT VT,
489 unsigned char TargetFlags = 0);
490 SDValue getValueType(EVT);
491 SDValue getRegister(unsigned Reg, EVT VT);
492 SDValue getRegisterMask(const uint32_t *RegMask);
493 SDValue getEHLabel(SDLoc dl, SDValue Root, MCSymbol *Label);
494 SDValue getBlockAddress(const BlockAddress *BA, EVT VT,
495 int64_t Offset = 0, bool isTarget = false,
496 unsigned char TargetFlags = 0);
497 SDValue getTargetBlockAddress(const BlockAddress *BA, EVT VT,
499 unsigned char TargetFlags = 0) {
500 return getBlockAddress(BA, VT, Offset, true, TargetFlags);
503 SDValue getCopyToReg(SDValue Chain, SDLoc dl, unsigned Reg, SDValue N) {
504 return getNode(ISD::CopyToReg, dl, MVT::Other, Chain,
505 getRegister(Reg, N.getValueType()), N);
508 // This version of the getCopyToReg method takes an extra operand, which
509 // indicates that there is potentially an incoming glue value (if Glue is not
510 // null) and that there should be a glue result.
511 SDValue getCopyToReg(SDValue Chain, SDLoc dl, unsigned Reg, SDValue N,
513 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
514 SDValue Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Glue };
515 return getNode(ISD::CopyToReg, dl, VTs,
516 ArrayRef<SDValue>(Ops, Glue.getNode() ? 4 : 3));
519 // Similar to last getCopyToReg() except parameter Reg is a SDValue
520 SDValue getCopyToReg(SDValue Chain, SDLoc dl, SDValue Reg, SDValue N,
522 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
523 SDValue Ops[] = { Chain, Reg, N, Glue };
524 return getNode(ISD::CopyToReg, dl, VTs,
525 ArrayRef<SDValue>(Ops, Glue.getNode() ? 4 : 3));
528 SDValue getCopyFromReg(SDValue Chain, SDLoc dl, unsigned Reg, EVT VT) {
529 SDVTList VTs = getVTList(VT, MVT::Other);
530 SDValue Ops[] = { Chain, getRegister(Reg, VT) };
531 return getNode(ISD::CopyFromReg, dl, VTs, Ops);
534 // This version of the getCopyFromReg method takes an extra operand, which
535 // indicates that there is potentially an incoming glue value (if Glue is not
536 // null) and that there should be a glue result.
537 SDValue getCopyFromReg(SDValue Chain, SDLoc dl, unsigned Reg, EVT VT,
539 SDVTList VTs = getVTList(VT, MVT::Other, MVT::Glue);
540 SDValue Ops[] = { Chain, getRegister(Reg, VT), Glue };
541 return getNode(ISD::CopyFromReg, dl, VTs,
542 ArrayRef<SDValue>(Ops, Glue.getNode() ? 3 : 2));
545 SDValue getCondCode(ISD::CondCode Cond);
547 /// Returns the ConvertRndSat Note: Avoid using this node because it may
548 /// disappear in the future and most targets don't support it.
549 SDValue getConvertRndSat(EVT VT, SDLoc dl, SDValue Val, SDValue DTy,
551 SDValue Rnd, SDValue Sat, ISD::CvtCode Code);
553 /// Return an ISD::VECTOR_SHUFFLE node. The number of elements in VT,
554 /// which must be a vector type, must match the number of mask elements
555 /// NumElts. An integer mask element equal to -1 is treated as undefined.
556 SDValue getVectorShuffle(EVT VT, SDLoc dl, SDValue N1, SDValue N2,
557 const int *MaskElts);
558 SDValue getVectorShuffle(EVT VT, SDLoc dl, SDValue N1, SDValue N2,
559 ArrayRef<int> MaskElts) {
560 assert(VT.getVectorNumElements() == MaskElts.size() &&
561 "Must have the same number of vector elements as mask elements!");
562 return getVectorShuffle(VT, dl, N1, N2, MaskElts.data());
565 /// \brief Returns an ISD::VECTOR_SHUFFLE node semantically equivalent to
566 /// the shuffle node in input but with swapped operands.
568 /// Example: shuffle A, B, <0,5,2,7> -> shuffle B, A, <4,1,6,3>
569 SDValue getCommutedVectorShuffle(const ShuffleVectorSDNode &SV);
571 /// Convert Op, which must be of integer type, to the
572 /// integer type VT, by either any-extending or truncating it.
573 SDValue getAnyExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
575 /// Convert Op, which must be of integer type, to the
576 /// integer type VT, by either sign-extending or truncating it.
577 SDValue getSExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
579 /// Convert Op, which must be of integer type, to the
580 /// integer type VT, by either zero-extending or truncating it.
581 SDValue getZExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
583 /// Return the expression required to zero extend the Op
584 /// value assuming it was the smaller SrcTy value.
585 SDValue getZeroExtendInReg(SDValue Op, SDLoc DL, EVT SrcTy);
587 /// Return an operation which will any-extend the low lanes of the operand
588 /// into the specified vector type. For example,
589 /// this can convert a v16i8 into a v4i32 by any-extending the low four
590 /// lanes of the operand from i8 to i32.
591 SDValue getAnyExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
593 /// Return an operation which will sign extend the low lanes of the operand
594 /// into the specified vector type. For example,
595 /// this can convert a v16i8 into a v4i32 by sign extending the low four
596 /// lanes of the operand from i8 to i32.
597 SDValue getSignExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
599 /// Return an operation which will zero extend the low lanes of the operand
600 /// into the specified vector type. For example,
601 /// this can convert a v16i8 into a v4i32 by zero extending the low four
602 /// lanes of the operand from i8 to i32.
603 SDValue getZeroExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
605 /// Convert Op, which must be of integer type, to the integer type VT,
606 /// by using an extension appropriate for the target's
607 /// BooleanContent for type OpVT or truncating it.
608 SDValue getBoolExtOrTrunc(SDValue Op, SDLoc SL, EVT VT, EVT OpVT);
610 /// Create a bitwise NOT operation as (XOR Val, -1).
611 SDValue getNOT(SDLoc DL, SDValue Val, EVT VT);
613 /// \brief Create a logical NOT operation as (XOR Val, BooleanOne).
614 SDValue getLogicalNOT(SDLoc DL, SDValue Val, EVT VT);
616 /// Return a new CALLSEQ_START node, which always must have a glue result
617 /// (to ensure it's not CSE'd). CALLSEQ_START does not have a useful SDLoc.
618 SDValue getCALLSEQ_START(SDValue Chain, SDValue Op, SDLoc DL) {
619 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
620 SDValue Ops[] = { Chain, Op };
621 return getNode(ISD::CALLSEQ_START, DL, VTs, Ops);
624 /// Return a new CALLSEQ_END node, which always must have a
625 /// glue result (to ensure it's not CSE'd).
626 /// CALLSEQ_END does not have a useful SDLoc.
627 SDValue getCALLSEQ_END(SDValue Chain, SDValue Op1, SDValue Op2,
628 SDValue InGlue, SDLoc DL) {
629 SDVTList NodeTys = getVTList(MVT::Other, MVT::Glue);
630 SmallVector<SDValue, 4> Ops;
631 Ops.push_back(Chain);
634 if (InGlue.getNode())
635 Ops.push_back(InGlue);
636 return getNode(ISD::CALLSEQ_END, DL, NodeTys, Ops);
639 /// Return an UNDEF node. UNDEF does not have a useful SDLoc.
640 SDValue getUNDEF(EVT VT) {
641 return getNode(ISD::UNDEF, SDLoc(), VT);
644 /// Return a GLOBAL_OFFSET_TABLE node. This does not have a useful SDLoc.
645 SDValue getGLOBAL_OFFSET_TABLE(EVT VT) {
646 return getNode(ISD::GLOBAL_OFFSET_TABLE, SDLoc(), VT);
649 /// Gets or creates the specified node.
651 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT);
652 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N);
653 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
654 bool nuw = false, bool nsw = false, bool exact = false);
655 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
657 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
658 SDValue N3, SDValue N4);
659 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
660 SDValue N3, SDValue N4, SDValue N5);
661 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, ArrayRef<SDUse> Ops);
662 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT,
663 ArrayRef<SDValue> Ops);
664 SDValue getNode(unsigned Opcode, SDLoc DL,
665 ArrayRef<EVT> ResultTys,
666 ArrayRef<SDValue> Ops);
667 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
668 ArrayRef<SDValue> Ops);
669 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs);
670 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N);
671 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
672 SDValue N1, SDValue N2);
673 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
674 SDValue N1, SDValue N2, SDValue N3);
675 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
676 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
677 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
678 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
681 /// Compute a TokenFactor to force all the incoming stack arguments to be
682 /// loaded from the stack. This is used in tail call lowering to protect
683 /// stack arguments from being clobbered.
684 SDValue getStackArgumentTokenFactor(SDValue Chain);
686 SDValue getMemcpy(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
687 SDValue Size, unsigned Align, bool isVol, bool AlwaysInline,
688 bool isTailCall, MachinePointerInfo DstPtrInfo,
689 MachinePointerInfo SrcPtrInfo);
691 SDValue getMemmove(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
692 SDValue Size, unsigned Align, bool isVol, bool isTailCall,
693 MachinePointerInfo DstPtrInfo,
694 MachinePointerInfo SrcPtrInfo);
696 SDValue getMemset(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
697 SDValue Size, unsigned Align, bool isVol, bool isTailCall,
698 MachinePointerInfo DstPtrInfo);
700 /// Helper function to make it easier to build SetCC's if you just
701 /// have an ISD::CondCode instead of an SDValue.
703 SDValue getSetCC(SDLoc DL, EVT VT, SDValue LHS, SDValue RHS,
704 ISD::CondCode Cond) {
705 assert(LHS.getValueType().isVector() == RHS.getValueType().isVector() &&
706 "Cannot compare scalars to vectors");
707 assert(LHS.getValueType().isVector() == VT.isVector() &&
708 "Cannot compare scalars to vectors");
709 assert(Cond != ISD::SETCC_INVALID &&
710 "Cannot create a setCC of an invalid node.");
711 return getNode(ISD::SETCC, DL, VT, LHS, RHS, getCondCode(Cond));
714 /// Helper function to make it easier to build Select's if you just
715 /// have operands and don't want to check for vector.
716 SDValue getSelect(SDLoc DL, EVT VT, SDValue Cond,
717 SDValue LHS, SDValue RHS) {
718 assert(LHS.getValueType() == RHS.getValueType() &&
719 "Cannot use select on differing types");
720 assert(VT.isVector() == LHS.getValueType().isVector() &&
721 "Cannot mix vectors and scalars");
722 return getNode(Cond.getValueType().isVector() ? ISD::VSELECT : ISD::SELECT, DL, VT,
726 /// Helper function to make it easier to build SelectCC's if you
727 /// just have an ISD::CondCode instead of an SDValue.
729 SDValue getSelectCC(SDLoc DL, SDValue LHS, SDValue RHS,
730 SDValue True, SDValue False, ISD::CondCode Cond) {
731 return getNode(ISD::SELECT_CC, DL, True.getValueType(),
732 LHS, RHS, True, False, getCondCode(Cond));
735 /// VAArg produces a result and token chain, and takes a pointer
736 /// and a source value as input.
737 SDValue getVAArg(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
738 SDValue SV, unsigned Align);
740 /// Gets a node for an atomic cmpxchg op. There are two
741 /// valid Opcodes. ISD::ATOMIC_CMO_SWAP produces the value loaded and a
742 /// chain result. ISD::ATOMIC_CMP_SWAP_WITH_SUCCESS produces the value loaded,
743 /// a success flag (initially i1), and a chain.
744 SDValue getAtomicCmpSwap(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTs,
745 SDValue Chain, SDValue Ptr, SDValue Cmp, SDValue Swp,
746 MachinePointerInfo PtrInfo, unsigned Alignment,
747 AtomicOrdering SuccessOrdering,
748 AtomicOrdering FailureOrdering,
749 SynchronizationScope SynchScope);
750 SDValue getAtomicCmpSwap(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTs,
751 SDValue Chain, SDValue Ptr, SDValue Cmp, SDValue Swp,
752 MachineMemOperand *MMO,
753 AtomicOrdering SuccessOrdering,
754 AtomicOrdering FailureOrdering,
755 SynchronizationScope SynchScope);
757 /// Gets a node for an atomic op, produces result (if relevant)
758 /// and chain and takes 2 operands.
759 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDValue Chain,
760 SDValue Ptr, SDValue Val, const Value *PtrVal,
761 unsigned Alignment, AtomicOrdering Ordering,
762 SynchronizationScope SynchScope);
763 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDValue Chain,
764 SDValue Ptr, SDValue Val, MachineMemOperand *MMO,
765 AtomicOrdering Ordering,
766 SynchronizationScope SynchScope);
768 /// Gets a node for an atomic op, produces result and chain and
770 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, EVT VT,
771 SDValue Chain, SDValue Ptr, MachineMemOperand *MMO,
772 AtomicOrdering Ordering,
773 SynchronizationScope SynchScope);
775 /// Gets a node for an atomic op, produces result and chain and takes N
777 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTList,
778 ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
779 AtomicOrdering SuccessOrdering,
780 AtomicOrdering FailureOrdering,
781 SynchronizationScope SynchScope);
782 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTList,
783 ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
784 AtomicOrdering Ordering, SynchronizationScope SynchScope);
786 /// Creates a MemIntrinsicNode that may produce a
787 /// result and takes a list of operands. Opcode may be INTRINSIC_VOID,
788 /// INTRINSIC_W_CHAIN, or a target-specific opcode with a value not
789 /// less than FIRST_TARGET_MEMORY_OPCODE.
790 SDValue getMemIntrinsicNode(unsigned Opcode, SDLoc dl, SDVTList VTList,
791 ArrayRef<SDValue> Ops,
792 EVT MemVT, MachinePointerInfo PtrInfo,
793 unsigned Align = 0, bool Vol = false,
794 bool ReadMem = true, bool WriteMem = true,
797 SDValue getMemIntrinsicNode(unsigned Opcode, SDLoc dl, SDVTList VTList,
798 ArrayRef<SDValue> Ops,
799 EVT MemVT, MachineMemOperand *MMO);
801 /// Create a MERGE_VALUES node from the given operands.
802 SDValue getMergeValues(ArrayRef<SDValue> Ops, SDLoc dl);
804 /// Loads are not normal binary operators: their result type is not
805 /// determined by their operands, and they produce a value AND a token chain.
807 SDValue getLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
808 MachinePointerInfo PtrInfo, bool isVolatile,
809 bool isNonTemporal, bool isInvariant, unsigned Alignment,
810 const AAMDNodes &AAInfo = AAMDNodes(),
811 const MDNode *Ranges = nullptr);
812 SDValue getLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
813 MachineMemOperand *MMO);
814 SDValue getExtLoad(ISD::LoadExtType ExtType, SDLoc dl, EVT VT,
815 SDValue Chain, SDValue Ptr, MachinePointerInfo PtrInfo,
816 EVT MemVT, bool isVolatile,
817 bool isNonTemporal, bool isInvariant, unsigned Alignment,
818 const AAMDNodes &AAInfo = AAMDNodes());
819 SDValue getExtLoad(ISD::LoadExtType ExtType, SDLoc dl, EVT VT,
820 SDValue Chain, SDValue Ptr, EVT MemVT,
821 MachineMemOperand *MMO);
822 SDValue getIndexedLoad(SDValue OrigLoad, SDLoc dl, SDValue Base,
823 SDValue Offset, ISD::MemIndexedMode AM);
824 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
826 SDValue Chain, SDValue Ptr, SDValue Offset,
827 MachinePointerInfo PtrInfo, EVT MemVT,
828 bool isVolatile, bool isNonTemporal, bool isInvariant,
829 unsigned Alignment, const AAMDNodes &AAInfo = AAMDNodes(),
830 const MDNode *Ranges = nullptr);
831 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
833 SDValue Chain, SDValue Ptr, SDValue Offset,
834 EVT MemVT, MachineMemOperand *MMO);
836 /// Helper function to build ISD::STORE nodes.
837 SDValue getStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
838 MachinePointerInfo PtrInfo, bool isVolatile,
839 bool isNonTemporal, unsigned Alignment,
840 const AAMDNodes &AAInfo = AAMDNodes());
841 SDValue getStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
842 MachineMemOperand *MMO);
843 SDValue getTruncStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
844 MachinePointerInfo PtrInfo, EVT TVT,
845 bool isNonTemporal, bool isVolatile,
847 const AAMDNodes &AAInfo = AAMDNodes());
848 SDValue getTruncStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
849 EVT TVT, MachineMemOperand *MMO);
850 SDValue getIndexedStore(SDValue OrigStoe, SDLoc dl, SDValue Base,
851 SDValue Offset, ISD::MemIndexedMode AM);
853 SDValue getMaskedLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
854 SDValue Mask, SDValue Src0, EVT MemVT,
855 MachineMemOperand *MMO, ISD::LoadExtType);
856 SDValue getMaskedStore(SDValue Chain, SDLoc dl, SDValue Val,
857 SDValue Ptr, SDValue Mask, EVT MemVT,
858 MachineMemOperand *MMO, bool IsTrunc);
859 SDValue getMaskedGather(SDVTList VTs, EVT VT, SDLoc dl,
860 ArrayRef<SDValue> Ops, MachineMemOperand *MMO);
861 SDValue getMaskedScatter(SDVTList VTs, EVT VT, SDLoc dl,
862 ArrayRef<SDValue> Ops, MachineMemOperand *MMO);
863 /// Construct a node to track a Value* through the backend.
864 SDValue getSrcValue(const Value *v);
866 /// Return an MDNodeSDNode which holds an MDNode.
867 SDValue getMDNode(const MDNode *MD);
869 /// Return an AddrSpaceCastSDNode.
870 SDValue getAddrSpaceCast(SDLoc dl, EVT VT, SDValue Ptr,
871 unsigned SrcAS, unsigned DestAS);
873 /// Return the specified value casted to
874 /// the target's desired shift amount type.
875 SDValue getShiftAmountOperand(EVT LHSTy, SDValue Op);
877 /// *Mutate* the specified node in-place to have the
878 /// specified operands. If the resultant node already exists in the DAG,
879 /// this does not modify the specified node, instead it returns the node that
880 /// already exists. If the resultant node does not exist in the DAG, the
881 /// input node is returned. As a degenerate case, if you specify the same
882 /// input operands as the node already has, the input node is returned.
883 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op);
884 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2);
885 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
887 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
888 SDValue Op3, SDValue Op4);
889 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
890 SDValue Op3, SDValue Op4, SDValue Op5);
891 SDNode *UpdateNodeOperands(SDNode *N, ArrayRef<SDValue> Ops);
893 /// These are used for target selectors to *mutate* the
894 /// specified node to have the specified return type, Target opcode, and
895 /// operands. Note that target opcodes are stored as
896 /// ~TargetOpcode in the node opcode field. The resultant node is returned.
897 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT);
898 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT, SDValue Op1);
899 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
900 SDValue Op1, SDValue Op2);
901 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
902 SDValue Op1, SDValue Op2, SDValue Op3);
903 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
904 ArrayRef<SDValue> Ops);
905 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1, EVT VT2);
906 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
907 EVT VT2, ArrayRef<SDValue> Ops);
908 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
909 EVT VT2, EVT VT3, ArrayRef<SDValue> Ops);
910 SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT1,
911 EVT VT2, EVT VT3, EVT VT4, ArrayRef<SDValue> Ops);
912 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
913 EVT VT2, SDValue Op1);
914 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
915 EVT VT2, SDValue Op1, SDValue Op2);
916 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
917 EVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
918 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
919 EVT VT2, EVT VT3, SDValue Op1, SDValue Op2, SDValue Op3);
920 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
921 ArrayRef<SDValue> Ops);
923 /// This *mutates* the specified node to have the specified
924 /// return type, opcode, and operands.
925 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
926 ArrayRef<SDValue> Ops);
928 /// These are used for target selectors to create a new node
929 /// with specified return type(s), MachineInstr opcode, and operands.
931 /// Note that getMachineNode returns the resultant node. If there is already
932 /// a node of the specified opcode and operands, it returns that node instead
933 /// of the current one.
934 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT);
935 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
937 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
938 SDValue Op1, SDValue Op2);
939 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
940 SDValue Op1, SDValue Op2, SDValue Op3);
941 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
942 ArrayRef<SDValue> Ops);
943 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2);
944 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
946 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
947 SDValue Op1, SDValue Op2);
948 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
949 SDValue Op1, SDValue Op2, SDValue Op3);
950 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
951 ArrayRef<SDValue> Ops);
952 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
953 EVT VT3, SDValue Op1, SDValue Op2);
954 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
955 EVT VT3, SDValue Op1, SDValue Op2,
957 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
958 EVT VT3, ArrayRef<SDValue> Ops);
959 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
960 EVT VT3, EVT VT4, ArrayRef<SDValue> Ops);
961 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl,
962 ArrayRef<EVT> ResultTys,
963 ArrayRef<SDValue> Ops);
964 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, SDVTList VTs,
965 ArrayRef<SDValue> Ops);
967 /// A convenience function for creating TargetInstrInfo::EXTRACT_SUBREG nodes.
968 SDValue getTargetExtractSubreg(int SRIdx, SDLoc DL, EVT VT,
971 /// A convenience function for creating TargetInstrInfo::INSERT_SUBREG nodes.
972 SDValue getTargetInsertSubreg(int SRIdx, SDLoc DL, EVT VT,
973 SDValue Operand, SDValue Subreg);
975 /// Get the specified node if it's already available, or else return NULL.
976 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs, ArrayRef<SDValue> Ops,
977 bool nuw = false, bool nsw = false,
980 /// Creates a SDDbgValue node.
981 SDDbgValue *getDbgValue(MDNode *Var, MDNode *Expr, SDNode *N, unsigned R,
982 bool IsIndirect, uint64_t Off, DebugLoc DL,
986 SDDbgValue *getConstantDbgValue(MDNode *Var, MDNode *Expr, const Value *C,
987 uint64_t Off, DebugLoc DL, unsigned O);
990 SDDbgValue *getFrameIndexDbgValue(MDNode *Var, MDNode *Expr, unsigned FI,
991 uint64_t Off, DebugLoc DL, unsigned O);
993 /// Remove the specified node from the system. If any of its
994 /// operands then becomes dead, remove them as well. Inform UpdateListener
995 /// for each node deleted.
996 void RemoveDeadNode(SDNode *N);
998 /// This method deletes the unreachable nodes in the
999 /// given list, and any nodes that become unreachable as a result.
1000 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes);
1002 /// Modify anything using 'From' to use 'To' instead.
1003 /// This can cause recursive merging of nodes in the DAG. Use the first
1004 /// version if 'From' is known to have a single result, use the second
1005 /// if you have two nodes with identical results (or if 'To' has a superset
1006 /// of the results of 'From'), use the third otherwise.
1008 /// These methods all take an optional UpdateListener, which (if not null) is
1009 /// informed about nodes that are deleted and modified due to recursive
1010 /// changes in the dag.
1012 /// These functions only replace all existing uses. It's possible that as
1013 /// these replacements are being performed, CSE may cause the From node
1014 /// to be given new uses. These new uses of From are left in place, and
1015 /// not automatically transferred to To.
1017 void ReplaceAllUsesWith(SDValue From, SDValue Op);
1018 void ReplaceAllUsesWith(SDNode *From, SDNode *To);
1019 void ReplaceAllUsesWith(SDNode *From, const SDValue *To);
1021 /// Replace any uses of From with To, leaving
1022 /// uses of other values produced by From.Val alone.
1023 void ReplaceAllUsesOfValueWith(SDValue From, SDValue To);
1025 /// Like ReplaceAllUsesOfValueWith, but for multiple values at once.
1026 /// This correctly handles the case where
1027 /// there is an overlap between the From values and the To values.
1028 void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To,
1031 /// Topological-sort the AllNodes list and a
1032 /// assign a unique node id for each node in the DAG based on their
1033 /// topological order. Returns the number of nodes.
1034 unsigned AssignTopologicalOrder();
1036 /// Move node N in the AllNodes list to be immediately
1037 /// before the given iterator Position. This may be used to update the
1038 /// topological ordering when the list of nodes is modified.
1039 void RepositionNode(allnodes_iterator Position, SDNode *N) {
1040 AllNodes.insert(Position, AllNodes.remove(N));
1043 /// Returns true if the opcode is a commutative binary operation.
1044 static bool isCommutativeBinOp(unsigned Opcode) {
1045 // FIXME: This should get its info from the td file, so that we can include
1052 case ISD::SMUL_LOHI:
1053 case ISD::UMUL_LOHI:
1066 default: return false;
1070 /// Returns an APFloat semantics tag appropriate for the given type. If VT is
1071 /// a vector type, the element semantics are returned.
1072 static const fltSemantics &EVTToAPFloatSemantics(EVT VT) {
1073 switch (VT.getScalarType().getSimpleVT().SimpleTy) {
1074 default: llvm_unreachable("Unknown FP format");
1075 case MVT::f16: return APFloat::IEEEhalf;
1076 case MVT::f32: return APFloat::IEEEsingle;
1077 case MVT::f64: return APFloat::IEEEdouble;
1078 case MVT::f80: return APFloat::x87DoubleExtended;
1079 case MVT::f128: return APFloat::IEEEquad;
1080 case MVT::ppcf128: return APFloat::PPCDoubleDouble;
1084 /// Add a dbg_value SDNode. If SD is non-null that means the
1085 /// value is produced by SD.
1086 void AddDbgValue(SDDbgValue *DB, SDNode *SD, bool isParameter);
1088 /// Get the debug values which reference the given SDNode.
1089 ArrayRef<SDDbgValue*> GetDbgValues(const SDNode* SD) {
1090 return DbgInfo->getSDDbgValues(SD);
1093 /// Transfer SDDbgValues.
1094 void TransferDbgValues(SDValue From, SDValue To);
1096 /// Return true if there are any SDDbgValue nodes associated
1097 /// with this SelectionDAG.
1098 bool hasDebugValues() const { return !DbgInfo->empty(); }
1100 SDDbgInfo::DbgIterator DbgBegin() { return DbgInfo->DbgBegin(); }
1101 SDDbgInfo::DbgIterator DbgEnd() { return DbgInfo->DbgEnd(); }
1102 SDDbgInfo::DbgIterator ByvalParmDbgBegin() {
1103 return DbgInfo->ByvalParmDbgBegin();
1105 SDDbgInfo::DbgIterator ByvalParmDbgEnd() {
1106 return DbgInfo->ByvalParmDbgEnd();
1111 /// Create a stack temporary, suitable for holding the
1112 /// specified value type. If minAlign is specified, the slot size will have
1113 /// at least that alignment.
1114 SDValue CreateStackTemporary(EVT VT, unsigned minAlign = 1);
1116 /// Create a stack temporary suitable for holding
1117 /// either of the specified value types.
1118 SDValue CreateStackTemporary(EVT VT1, EVT VT2);
1120 SDValue FoldConstantArithmetic(unsigned Opcode, EVT VT,
1121 SDNode *Cst1, SDNode *Cst2);
1123 /// Constant fold a setcc to true or false.
1124 SDValue FoldSetCC(EVT VT, SDValue N1,
1125 SDValue N2, ISD::CondCode Cond, SDLoc dl);
1127 /// Return true if the sign bit of Op is known to be zero.
1128 /// We use this predicate to simplify operations downstream.
1129 bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const;
1131 /// Return true if 'Op & Mask' is known to be zero. We
1132 /// use this predicate to simplify operations downstream. Op and Mask are
1133 /// known to be the same type.
1134 bool MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth = 0)
1137 /// Determine which bits of Op are known to be either zero or one and return
1138 /// them in the KnownZero/KnownOne bitsets. Targets can implement the
1139 /// computeKnownBitsForTargetNode method in the TargetLowering class to allow
1140 /// target nodes to be understood.
1141 void computeKnownBits(SDValue Op, APInt &KnownZero, APInt &KnownOne,
1142 unsigned Depth = 0) const;
1144 /// Return the number of times the sign bit of the
1145 /// register is replicated into the other bits. We know that at least 1 bit
1146 /// is always equal to the sign bit (itself), but other cases can give us
1147 /// information. For example, immediately after an "SRA X, 2", we know that
1148 /// the top 3 bits are all equal to each other, so we return 3. Targets can
1149 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
1150 /// class to allow target nodes to be understood.
1151 unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const;
1153 /// Return true if the specified operand is an
1154 /// ISD::ADD with a ConstantSDNode on the right-hand side, or if it is an
1155 /// ISD::OR with a ConstantSDNode that is guaranteed to have the same
1156 /// semantics as an ADD. This handles the equivalence:
1157 /// X|Cst == X+Cst iff X&Cst = 0.
1158 bool isBaseWithConstantOffset(SDValue Op) const;
1160 /// Test whether the given SDValue is known to never be NaN.
1161 bool isKnownNeverNaN(SDValue Op) const;
1163 /// Test whether the given SDValue is known to never be
1164 /// positive or negative Zero.
1165 bool isKnownNeverZero(SDValue Op) const;
1167 /// Test whether two SDValues are known to compare equal. This
1168 /// is true if they are the same value, or if one is negative zero and the
1169 /// other positive zero.
1170 bool isEqualTo(SDValue A, SDValue B) const;
1172 /// Utility function used by legalize and lowering to
1173 /// "unroll" a vector operation by splitting out the scalars and operating
1174 /// on each element individually. If the ResNE is 0, fully unroll the vector
1175 /// op. If ResNE is less than the width of the vector op, unroll up to ResNE.
1176 /// If the ResNE is greater than the width of the vector op, unroll the
1177 /// vector op and fill the end of the resulting vector with UNDEFS.
1178 SDValue UnrollVectorOp(SDNode *N, unsigned ResNE = 0);
1180 /// Return true if LD is loading 'Bytes' bytes from a location that is 'Dist'
1181 /// units away from the location that the 'Base' load is loading from.
1182 bool isConsecutiveLoad(LoadSDNode *LD, LoadSDNode *Base,
1183 unsigned Bytes, int Dist) const;
1185 /// Infer alignment of a load / store address. Return 0 if
1186 /// it cannot be inferred.
1187 unsigned InferPtrAlignment(SDValue Ptr) const;
1189 /// Compute the VTs needed for the low/hi parts of a type
1190 /// which is split (or expanded) into two not necessarily identical pieces.
1191 std::pair<EVT, EVT> GetSplitDestVTs(const EVT &VT) const;
1193 /// Split the vector with EXTRACT_SUBVECTOR using the provides
1194 /// VTs and return the low/high part.
1195 std::pair<SDValue, SDValue> SplitVector(const SDValue &N, const SDLoc &DL,
1196 const EVT &LoVT, const EVT &HiVT);
1198 /// Split the vector with EXTRACT_SUBVECTOR and return the low/high part.
1199 std::pair<SDValue, SDValue> SplitVector(const SDValue &N, const SDLoc &DL) {
1201 std::tie(LoVT, HiVT) = GetSplitDestVTs(N.getValueType());
1202 return SplitVector(N, DL, LoVT, HiVT);
1205 /// Split the node's operand with EXTRACT_SUBVECTOR and
1206 /// return the low/high part.
1207 std::pair<SDValue, SDValue> SplitVectorOperand(const SDNode *N, unsigned OpNo)
1209 return SplitVector(N->getOperand(OpNo), SDLoc(N));
1212 /// Append the extracted elements from Start to Count out of the vector Op
1213 /// in Args. If Count is 0, all of the elements will be extracted.
1214 void ExtractVectorElements(SDValue Op, SmallVectorImpl<SDValue> &Args,
1215 unsigned Start = 0, unsigned Count = 0);
1217 unsigned getEVTAlignment(EVT MemoryVT) const;
1220 void InsertNode(SDNode *N);
1221 bool RemoveNodeFromCSEMaps(SDNode *N);
1222 void AddModifiedNodeToCSEMaps(SDNode *N);
1223 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos);
1224 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2,
1226 SDNode *FindModifiedNodeSlot(SDNode *N, ArrayRef<SDValue> Ops,
1228 SDNode *UpdadeSDLocOnMergedSDNode(SDNode *N, SDLoc loc);
1230 void DeleteNodeNotInCSEMaps(SDNode *N);
1231 void DeallocateNode(SDNode *N);
1233 void allnodes_clear();
1235 BinarySDNode *GetBinarySDNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
1236 SDValue N1, SDValue N2, bool nuw, bool nsw,
1239 /// List of non-single value types.
1240 FoldingSet<SDVTListNode> VTListMap;
1242 /// Maps to auto-CSE operations.
1243 std::vector<CondCodeSDNode*> CondCodeNodes;
1245 std::vector<SDNode*> ValueTypeNodes;
1246 std::map<EVT, SDNode*, EVT::compareRawBits> ExtendedValueTypeNodes;
1247 StringMap<SDNode*> ExternalSymbols;
1249 std::map<std::pair<std::string, unsigned char>,SDNode*> TargetExternalSymbols;
1252 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
1253 typedef SelectionDAG::allnodes_iterator nodes_iterator;
1254 static nodes_iterator nodes_begin(SelectionDAG *G) {
1255 return G->allnodes_begin();
1257 static nodes_iterator nodes_end(SelectionDAG *G) {
1258 return G->allnodes_end();
1262 } // end namespace llvm