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, SDLoc DL, EVT VT, bool isTarget = false,
417 bool isOpaque = false);
418 SDValue getConstant(const APInt &Val, SDLoc DL, EVT VT, bool isTarget = false,
419 bool isOpaque = false);
420 SDValue getConstant(const ConstantInt &Val, SDLoc DL, EVT VT,
421 bool isTarget = false, bool isOpaque = false);
422 SDValue getIntPtrConstant(uint64_t Val, SDLoc DL, bool isTarget = false);
423 SDValue getTargetConstant(uint64_t Val, SDLoc DL, EVT VT,
424 bool isOpaque = false) {
425 return getConstant(Val, DL, VT, true, isOpaque);
427 SDValue getTargetConstant(const APInt &Val, SDLoc DL, EVT VT,
428 bool isOpaque = false) {
429 return getConstant(Val, DL, VT, true, isOpaque);
431 SDValue getTargetConstant(const ConstantInt &Val, SDLoc DL, EVT VT,
432 bool isOpaque = false) {
433 return getConstant(Val, DL, VT, true, isOpaque);
435 // The forms below that take a double should only be used for simple
436 // constants that can be exactly represented in VT. No checks are made.
437 SDValue getConstantFP(double Val, SDLoc DL, EVT VT, bool isTarget = false);
438 SDValue getConstantFP(const APFloat& Val, SDLoc DL, EVT VT,
439 bool isTarget = false);
440 SDValue getConstantFP(const ConstantFP &CF, SDLoc DL, EVT VT,
441 bool isTarget = false);
442 SDValue getTargetConstantFP(double Val, SDLoc DL, EVT VT) {
443 return getConstantFP(Val, DL, VT, true);
445 SDValue getTargetConstantFP(const APFloat& Val, SDLoc DL, EVT VT) {
446 return getConstantFP(Val, DL, VT, true);
448 SDValue getTargetConstantFP(const ConstantFP &Val, SDLoc DL, EVT VT) {
449 return getConstantFP(Val, DL, VT, true);
451 SDValue getGlobalAddress(const GlobalValue *GV, SDLoc DL, EVT VT,
452 int64_t offset = 0, bool isTargetGA = false,
453 unsigned char TargetFlags = 0);
454 SDValue getTargetGlobalAddress(const GlobalValue *GV, SDLoc DL, EVT VT,
456 unsigned char TargetFlags = 0) {
457 return getGlobalAddress(GV, DL, VT, offset, true, TargetFlags);
459 SDValue getFrameIndex(int FI, EVT VT, bool isTarget = false);
460 SDValue getTargetFrameIndex(int FI, EVT VT) {
461 return getFrameIndex(FI, VT, true);
463 SDValue getJumpTable(int JTI, EVT VT, bool isTarget = false,
464 unsigned char TargetFlags = 0);
465 SDValue getTargetJumpTable(int JTI, EVT VT, unsigned char TargetFlags = 0) {
466 return getJumpTable(JTI, VT, true, TargetFlags);
468 SDValue getConstantPool(const Constant *C, EVT VT,
469 unsigned Align = 0, int Offs = 0, bool isT=false,
470 unsigned char TargetFlags = 0);
471 SDValue getTargetConstantPool(const Constant *C, EVT VT,
472 unsigned Align = 0, int Offset = 0,
473 unsigned char TargetFlags = 0) {
474 return getConstantPool(C, VT, Align, Offset, true, TargetFlags);
476 SDValue getConstantPool(MachineConstantPoolValue *C, EVT VT,
477 unsigned Align = 0, int Offs = 0, bool isT=false,
478 unsigned char TargetFlags = 0);
479 SDValue getTargetConstantPool(MachineConstantPoolValue *C,
480 EVT VT, unsigned Align = 0,
481 int Offset = 0, unsigned char TargetFlags=0) {
482 return getConstantPool(C, VT, Align, Offset, true, TargetFlags);
484 SDValue getTargetIndex(int Index, EVT VT, int64_t Offset = 0,
485 unsigned char TargetFlags = 0);
486 // When generating a branch to a BB, we don't in general know enough
487 // to provide debug info for the BB at that time, so keep this one around.
488 SDValue getBasicBlock(MachineBasicBlock *MBB);
489 SDValue getBasicBlock(MachineBasicBlock *MBB, SDLoc dl);
490 SDValue getExternalSymbol(const char *Sym, EVT VT);
491 SDValue getExternalSymbol(const char *Sym, SDLoc dl, EVT VT);
492 SDValue getTargetExternalSymbol(const char *Sym, EVT VT,
493 unsigned char TargetFlags = 0);
494 SDValue getValueType(EVT);
495 SDValue getRegister(unsigned Reg, EVT VT);
496 SDValue getRegisterMask(const uint32_t *RegMask);
497 SDValue getEHLabel(SDLoc dl, SDValue Root, MCSymbol *Label);
498 SDValue getBlockAddress(const BlockAddress *BA, EVT VT,
499 int64_t Offset = 0, bool isTarget = false,
500 unsigned char TargetFlags = 0);
501 SDValue getTargetBlockAddress(const BlockAddress *BA, EVT VT,
503 unsigned char TargetFlags = 0) {
504 return getBlockAddress(BA, VT, Offset, true, TargetFlags);
507 SDValue getCopyToReg(SDValue Chain, SDLoc dl, unsigned Reg, SDValue N) {
508 return getNode(ISD::CopyToReg, dl, MVT::Other, Chain,
509 getRegister(Reg, N.getValueType()), N);
512 // This version of the getCopyToReg method takes an extra operand, which
513 // indicates that there is potentially an incoming glue value (if Glue is not
514 // null) and that there should be a glue result.
515 SDValue getCopyToReg(SDValue Chain, SDLoc dl, unsigned Reg, SDValue N,
517 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
518 SDValue Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Glue };
519 return getNode(ISD::CopyToReg, dl, VTs,
520 ArrayRef<SDValue>(Ops, Glue.getNode() ? 4 : 3));
523 // Similar to last getCopyToReg() except parameter Reg is a SDValue
524 SDValue getCopyToReg(SDValue Chain, SDLoc dl, SDValue Reg, SDValue N,
526 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
527 SDValue Ops[] = { Chain, Reg, N, Glue };
528 return getNode(ISD::CopyToReg, dl, VTs,
529 ArrayRef<SDValue>(Ops, Glue.getNode() ? 4 : 3));
532 SDValue getCopyFromReg(SDValue Chain, SDLoc dl, unsigned Reg, EVT VT) {
533 SDVTList VTs = getVTList(VT, MVT::Other);
534 SDValue Ops[] = { Chain, getRegister(Reg, VT) };
535 return getNode(ISD::CopyFromReg, dl, VTs, Ops);
538 // This version of the getCopyFromReg method takes an extra operand, which
539 // indicates that there is potentially an incoming glue value (if Glue is not
540 // null) and that there should be a glue result.
541 SDValue getCopyFromReg(SDValue Chain, SDLoc dl, unsigned Reg, EVT VT,
543 SDVTList VTs = getVTList(VT, MVT::Other, MVT::Glue);
544 SDValue Ops[] = { Chain, getRegister(Reg, VT), Glue };
545 return getNode(ISD::CopyFromReg, dl, VTs,
546 ArrayRef<SDValue>(Ops, Glue.getNode() ? 3 : 2));
549 SDValue getCondCode(ISD::CondCode Cond);
551 /// Returns the ConvertRndSat Note: Avoid using this node because it may
552 /// disappear in the future and most targets don't support it.
553 SDValue getConvertRndSat(EVT VT, SDLoc dl, SDValue Val, SDValue DTy,
555 SDValue Rnd, SDValue Sat, ISD::CvtCode Code);
557 /// Return an ISD::VECTOR_SHUFFLE node. The number of elements in VT,
558 /// which must be a vector type, must match the number of mask elements
559 /// NumElts. An integer mask element equal to -1 is treated as undefined.
560 SDValue getVectorShuffle(EVT VT, SDLoc dl, SDValue N1, SDValue N2,
561 const int *MaskElts);
562 SDValue getVectorShuffle(EVT VT, SDLoc dl, SDValue N1, SDValue N2,
563 ArrayRef<int> MaskElts) {
564 assert(VT.getVectorNumElements() == MaskElts.size() &&
565 "Must have the same number of vector elements as mask elements!");
566 return getVectorShuffle(VT, dl, N1, N2, MaskElts.data());
569 /// \brief Returns an ISD::VECTOR_SHUFFLE node semantically equivalent to
570 /// the shuffle node in input but with swapped operands.
572 /// Example: shuffle A, B, <0,5,2,7> -> shuffle B, A, <4,1,6,3>
573 SDValue getCommutedVectorShuffle(const ShuffleVectorSDNode &SV);
575 /// Convert Op, which must be of integer type, to the
576 /// integer type VT, by either any-extending or truncating it.
577 SDValue getAnyExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
579 /// Convert Op, which must be of integer type, to the
580 /// integer type VT, by either sign-extending or truncating it.
581 SDValue getSExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
583 /// Convert Op, which must be of integer type, to the
584 /// integer type VT, by either zero-extending or truncating it.
585 SDValue getZExtOrTrunc(SDValue Op, SDLoc DL, EVT VT);
587 /// Return the expression required to zero extend the Op
588 /// value assuming it was the smaller SrcTy value.
589 SDValue getZeroExtendInReg(SDValue Op, SDLoc DL, EVT SrcTy);
591 /// Return an operation which will any-extend the low lanes of the operand
592 /// into the specified vector type. For example,
593 /// this can convert a v16i8 into a v4i32 by any-extending the low four
594 /// lanes of the operand from i8 to i32.
595 SDValue getAnyExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
597 /// Return an operation which will sign extend the low lanes of the operand
598 /// into the specified vector type. For example,
599 /// this can convert a v16i8 into a v4i32 by sign extending the low four
600 /// lanes of the operand from i8 to i32.
601 SDValue getSignExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
603 /// Return an operation which will zero extend the low lanes of the operand
604 /// into the specified vector type. For example,
605 /// this can convert a v16i8 into a v4i32 by zero extending the low four
606 /// lanes of the operand from i8 to i32.
607 SDValue getZeroExtendVectorInReg(SDValue Op, SDLoc DL, EVT VT);
609 /// Convert Op, which must be of integer type, to the integer type VT,
610 /// by using an extension appropriate for the target's
611 /// BooleanContent for type OpVT or truncating it.
612 SDValue getBoolExtOrTrunc(SDValue Op, SDLoc SL, EVT VT, EVT OpVT);
614 /// Create a bitwise NOT operation as (XOR Val, -1).
615 SDValue getNOT(SDLoc DL, SDValue Val, EVT VT);
617 /// \brief Create a logical NOT operation as (XOR Val, BooleanOne).
618 SDValue getLogicalNOT(SDLoc DL, SDValue Val, EVT VT);
620 /// Return a new CALLSEQ_START node, which always must have a glue result
621 /// (to ensure it's not CSE'd). CALLSEQ_START does not have a useful SDLoc.
622 SDValue getCALLSEQ_START(SDValue Chain, SDValue Op, SDLoc DL) {
623 SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
624 SDValue Ops[] = { Chain, Op };
625 return getNode(ISD::CALLSEQ_START, DL, VTs, Ops);
628 /// Return a new CALLSEQ_END node, which always must have a
629 /// glue result (to ensure it's not CSE'd).
630 /// CALLSEQ_END does not have a useful SDLoc.
631 SDValue getCALLSEQ_END(SDValue Chain, SDValue Op1, SDValue Op2,
632 SDValue InGlue, SDLoc DL) {
633 SDVTList NodeTys = getVTList(MVT::Other, MVT::Glue);
634 SmallVector<SDValue, 4> Ops;
635 Ops.push_back(Chain);
638 if (InGlue.getNode())
639 Ops.push_back(InGlue);
640 return getNode(ISD::CALLSEQ_END, DL, NodeTys, Ops);
643 /// Return an UNDEF node. UNDEF does not have a useful SDLoc.
644 SDValue getUNDEF(EVT VT) {
645 return getNode(ISD::UNDEF, SDLoc(), VT);
648 /// Return a GLOBAL_OFFSET_TABLE node. This does not have a useful SDLoc.
649 SDValue getGLOBAL_OFFSET_TABLE(EVT VT) {
650 return getNode(ISD::GLOBAL_OFFSET_TABLE, SDLoc(), VT);
653 /// Gets or creates the specified node.
655 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT);
656 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N);
657 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
658 const SDNodeFlags *Flags = nullptr);
659 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
661 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
662 SDValue N3, SDValue N4);
663 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, SDValue N1, SDValue N2,
664 SDValue N3, SDValue N4, SDValue N5);
665 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT, ArrayRef<SDUse> Ops);
666 SDValue getNode(unsigned Opcode, SDLoc DL, EVT VT,
667 ArrayRef<SDValue> Ops);
668 SDValue getNode(unsigned Opcode, SDLoc DL,
669 ArrayRef<EVT> ResultTys,
670 ArrayRef<SDValue> Ops);
671 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
672 ArrayRef<SDValue> Ops);
673 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs);
674 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs, SDValue N);
675 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
676 SDValue N1, SDValue N2);
677 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
678 SDValue N1, SDValue N2, SDValue N3);
679 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
680 SDValue N1, SDValue N2, SDValue N3, SDValue N4);
681 SDValue getNode(unsigned Opcode, SDLoc DL, SDVTList VTs,
682 SDValue N1, SDValue N2, SDValue N3, SDValue N4,
685 /// Compute a TokenFactor to force all the incoming stack arguments to be
686 /// loaded from the stack. This is used in tail call lowering to protect
687 /// stack arguments from being clobbered.
688 SDValue getStackArgumentTokenFactor(SDValue Chain);
690 SDValue getMemcpy(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
691 SDValue Size, unsigned Align, bool isVol, bool AlwaysInline,
692 bool isTailCall, MachinePointerInfo DstPtrInfo,
693 MachinePointerInfo SrcPtrInfo);
695 SDValue getMemmove(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
696 SDValue Size, unsigned Align, bool isVol, bool isTailCall,
697 MachinePointerInfo DstPtrInfo,
698 MachinePointerInfo SrcPtrInfo);
700 SDValue getMemset(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
701 SDValue Size, unsigned Align, bool isVol, bool isTailCall,
702 MachinePointerInfo DstPtrInfo);
704 /// Helper function to make it easier to build SetCC's if you just
705 /// have an ISD::CondCode instead of an SDValue.
707 SDValue getSetCC(SDLoc DL, EVT VT, SDValue LHS, SDValue RHS,
708 ISD::CondCode Cond) {
709 assert(LHS.getValueType().isVector() == RHS.getValueType().isVector() &&
710 "Cannot compare scalars to vectors");
711 assert(LHS.getValueType().isVector() == VT.isVector() &&
712 "Cannot compare scalars to vectors");
713 assert(Cond != ISD::SETCC_INVALID &&
714 "Cannot create a setCC of an invalid node.");
715 return getNode(ISD::SETCC, DL, VT, LHS, RHS, getCondCode(Cond));
718 /// Helper function to make it easier to build Select's if you just
719 /// have operands and don't want to check for vector.
720 SDValue getSelect(SDLoc DL, EVT VT, SDValue Cond,
721 SDValue LHS, SDValue RHS) {
722 assert(LHS.getValueType() == RHS.getValueType() &&
723 "Cannot use select on differing types");
724 assert(VT.isVector() == LHS.getValueType().isVector() &&
725 "Cannot mix vectors and scalars");
726 return getNode(Cond.getValueType().isVector() ? ISD::VSELECT : ISD::SELECT, DL, VT,
730 /// Helper function to make it easier to build SelectCC's if you
731 /// just have an ISD::CondCode instead of an SDValue.
733 SDValue getSelectCC(SDLoc DL, SDValue LHS, SDValue RHS,
734 SDValue True, SDValue False, ISD::CondCode Cond) {
735 return getNode(ISD::SELECT_CC, DL, True.getValueType(),
736 LHS, RHS, True, False, getCondCode(Cond));
739 /// VAArg produces a result and token chain, and takes a pointer
740 /// and a source value as input.
741 SDValue getVAArg(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
742 SDValue SV, unsigned Align);
744 /// Gets a node for an atomic cmpxchg op. There are two
745 /// valid Opcodes. ISD::ATOMIC_CMO_SWAP produces the value loaded and a
746 /// chain result. ISD::ATOMIC_CMP_SWAP_WITH_SUCCESS produces the value loaded,
747 /// a success flag (initially i1), and a chain.
748 SDValue getAtomicCmpSwap(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTs,
749 SDValue Chain, SDValue Ptr, SDValue Cmp, SDValue Swp,
750 MachinePointerInfo PtrInfo, unsigned Alignment,
751 AtomicOrdering SuccessOrdering,
752 AtomicOrdering FailureOrdering,
753 SynchronizationScope SynchScope);
754 SDValue getAtomicCmpSwap(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTs,
755 SDValue Chain, SDValue Ptr, SDValue Cmp, SDValue Swp,
756 MachineMemOperand *MMO,
757 AtomicOrdering SuccessOrdering,
758 AtomicOrdering FailureOrdering,
759 SynchronizationScope SynchScope);
761 /// Gets a node for an atomic op, produces result (if relevant)
762 /// and chain and takes 2 operands.
763 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDValue Chain,
764 SDValue Ptr, SDValue Val, const Value *PtrVal,
765 unsigned Alignment, AtomicOrdering Ordering,
766 SynchronizationScope SynchScope);
767 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDValue Chain,
768 SDValue Ptr, SDValue Val, MachineMemOperand *MMO,
769 AtomicOrdering Ordering,
770 SynchronizationScope SynchScope);
772 /// Gets a node for an atomic op, produces result and chain and
774 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, EVT VT,
775 SDValue Chain, SDValue Ptr, MachineMemOperand *MMO,
776 AtomicOrdering Ordering,
777 SynchronizationScope SynchScope);
779 /// Gets a node for an atomic op, produces result and chain and takes N
781 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTList,
782 ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
783 AtomicOrdering SuccessOrdering,
784 AtomicOrdering FailureOrdering,
785 SynchronizationScope SynchScope);
786 SDValue getAtomic(unsigned Opcode, SDLoc dl, EVT MemVT, SDVTList VTList,
787 ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
788 AtomicOrdering Ordering, SynchronizationScope SynchScope);
790 /// Creates a MemIntrinsicNode that may produce a
791 /// result and takes a list of operands. Opcode may be INTRINSIC_VOID,
792 /// INTRINSIC_W_CHAIN, or a target-specific opcode with a value not
793 /// less than FIRST_TARGET_MEMORY_OPCODE.
794 SDValue getMemIntrinsicNode(unsigned Opcode, SDLoc dl, SDVTList VTList,
795 ArrayRef<SDValue> Ops,
796 EVT MemVT, MachinePointerInfo PtrInfo,
797 unsigned Align = 0, bool Vol = false,
798 bool ReadMem = true, bool WriteMem = true,
801 SDValue getMemIntrinsicNode(unsigned Opcode, SDLoc dl, SDVTList VTList,
802 ArrayRef<SDValue> Ops,
803 EVT MemVT, MachineMemOperand *MMO);
805 /// Create a MERGE_VALUES node from the given operands.
806 SDValue getMergeValues(ArrayRef<SDValue> Ops, SDLoc dl);
808 /// Loads are not normal binary operators: their result type is not
809 /// determined by their operands, and they produce a value AND a token chain.
811 SDValue getLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
812 MachinePointerInfo PtrInfo, bool isVolatile,
813 bool isNonTemporal, bool isInvariant, unsigned Alignment,
814 const AAMDNodes &AAInfo = AAMDNodes(),
815 const MDNode *Ranges = nullptr);
816 SDValue getLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
817 MachineMemOperand *MMO);
818 SDValue getExtLoad(ISD::LoadExtType ExtType, SDLoc dl, EVT VT,
819 SDValue Chain, SDValue Ptr, MachinePointerInfo PtrInfo,
820 EVT MemVT, bool isVolatile,
821 bool isNonTemporal, bool isInvariant, unsigned Alignment,
822 const AAMDNodes &AAInfo = AAMDNodes());
823 SDValue getExtLoad(ISD::LoadExtType ExtType, SDLoc dl, EVT VT,
824 SDValue Chain, SDValue Ptr, EVT MemVT,
825 MachineMemOperand *MMO);
826 SDValue getIndexedLoad(SDValue OrigLoad, SDLoc dl, SDValue Base,
827 SDValue Offset, ISD::MemIndexedMode AM);
828 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
830 SDValue Chain, SDValue Ptr, SDValue Offset,
831 MachinePointerInfo PtrInfo, EVT MemVT,
832 bool isVolatile, bool isNonTemporal, bool isInvariant,
833 unsigned Alignment, const AAMDNodes &AAInfo = AAMDNodes(),
834 const MDNode *Ranges = nullptr);
835 SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
837 SDValue Chain, SDValue Ptr, SDValue Offset,
838 EVT MemVT, MachineMemOperand *MMO);
840 /// Helper function to build ISD::STORE nodes.
841 SDValue getStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
842 MachinePointerInfo PtrInfo, bool isVolatile,
843 bool isNonTemporal, unsigned Alignment,
844 const AAMDNodes &AAInfo = AAMDNodes());
845 SDValue getStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
846 MachineMemOperand *MMO);
847 SDValue getTruncStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
848 MachinePointerInfo PtrInfo, EVT TVT,
849 bool isNonTemporal, bool isVolatile,
851 const AAMDNodes &AAInfo = AAMDNodes());
852 SDValue getTruncStore(SDValue Chain, SDLoc dl, SDValue Val, SDValue Ptr,
853 EVT TVT, MachineMemOperand *MMO);
854 SDValue getIndexedStore(SDValue OrigStoe, SDLoc dl, SDValue Base,
855 SDValue Offset, ISD::MemIndexedMode AM);
857 SDValue getMaskedLoad(EVT VT, SDLoc dl, SDValue Chain, SDValue Ptr,
858 SDValue Mask, SDValue Src0, EVT MemVT,
859 MachineMemOperand *MMO, ISD::LoadExtType);
860 SDValue getMaskedStore(SDValue Chain, SDLoc dl, SDValue Val,
861 SDValue Ptr, SDValue Mask, EVT MemVT,
862 MachineMemOperand *MMO, bool IsTrunc);
863 SDValue getMaskedGather(SDVTList VTs, EVT VT, SDLoc dl,
864 ArrayRef<SDValue> Ops, MachineMemOperand *MMO);
865 SDValue getMaskedScatter(SDVTList VTs, EVT VT, SDLoc dl,
866 ArrayRef<SDValue> Ops, MachineMemOperand *MMO);
867 /// Construct a node to track a Value* through the backend.
868 SDValue getSrcValue(const Value *v);
870 /// Return an MDNodeSDNode which holds an MDNode.
871 SDValue getMDNode(const MDNode *MD);
873 /// Return an AddrSpaceCastSDNode.
874 SDValue getAddrSpaceCast(SDLoc dl, EVT VT, SDValue Ptr,
875 unsigned SrcAS, unsigned DestAS);
877 /// Return the specified value casted to
878 /// the target's desired shift amount type.
879 SDValue getShiftAmountOperand(EVT LHSTy, SDValue Op);
881 /// *Mutate* the specified node in-place to have the
882 /// specified operands. If the resultant node already exists in the DAG,
883 /// this does not modify the specified node, instead it returns the node that
884 /// already exists. If the resultant node does not exist in the DAG, the
885 /// input node is returned. As a degenerate case, if you specify the same
886 /// input operands as the node already has, the input node is returned.
887 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op);
888 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2);
889 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
891 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
892 SDValue Op3, SDValue Op4);
893 SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
894 SDValue Op3, SDValue Op4, SDValue Op5);
895 SDNode *UpdateNodeOperands(SDNode *N, ArrayRef<SDValue> Ops);
897 /// These are used for target selectors to *mutate* the
898 /// specified node to have the specified return type, Target opcode, and
899 /// operands. Note that target opcodes are stored as
900 /// ~TargetOpcode in the node opcode field. The resultant node is returned.
901 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT);
902 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT, SDValue Op1);
903 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
904 SDValue Op1, SDValue Op2);
905 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
906 SDValue Op1, SDValue Op2, SDValue Op3);
907 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT,
908 ArrayRef<SDValue> Ops);
909 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1, EVT VT2);
910 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
911 EVT VT2, ArrayRef<SDValue> Ops);
912 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
913 EVT VT2, EVT VT3, ArrayRef<SDValue> Ops);
914 SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT1,
915 EVT VT2, EVT VT3, EVT VT4, ArrayRef<SDValue> Ops);
916 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
917 EVT VT2, SDValue Op1);
918 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
919 EVT VT2, SDValue Op1, SDValue Op2);
920 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
921 EVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
922 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, EVT VT1,
923 EVT VT2, EVT VT3, SDValue Op1, SDValue Op2, SDValue Op3);
924 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
925 ArrayRef<SDValue> Ops);
927 /// This *mutates* the specified node to have the specified
928 /// return type, opcode, and operands.
929 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
930 ArrayRef<SDValue> Ops);
932 /// These are used for target selectors to create a new node
933 /// with specified return type(s), MachineInstr opcode, and operands.
935 /// Note that getMachineNode returns the resultant node. If there is already
936 /// a node of the specified opcode and operands, it returns that node instead
937 /// of the current one.
938 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT);
939 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
941 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
942 SDValue Op1, SDValue Op2);
943 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
944 SDValue Op1, SDValue Op2, SDValue Op3);
945 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT,
946 ArrayRef<SDValue> Ops);
947 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2);
948 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
950 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
951 SDValue Op1, SDValue Op2);
952 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
953 SDValue Op1, SDValue Op2, SDValue Op3);
954 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
955 ArrayRef<SDValue> Ops);
956 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
957 EVT VT3, SDValue Op1, SDValue Op2);
958 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
959 EVT VT3, SDValue Op1, SDValue Op2,
961 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
962 EVT VT3, ArrayRef<SDValue> Ops);
963 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, EVT VT1, EVT VT2,
964 EVT VT3, EVT VT4, ArrayRef<SDValue> Ops);
965 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl,
966 ArrayRef<EVT> ResultTys,
967 ArrayRef<SDValue> Ops);
968 MachineSDNode *getMachineNode(unsigned Opcode, SDLoc dl, SDVTList VTs,
969 ArrayRef<SDValue> Ops);
971 /// A convenience function for creating TargetInstrInfo::EXTRACT_SUBREG nodes.
972 SDValue getTargetExtractSubreg(int SRIdx, SDLoc DL, EVT VT,
975 /// A convenience function for creating TargetInstrInfo::INSERT_SUBREG nodes.
976 SDValue getTargetInsertSubreg(int SRIdx, SDLoc DL, EVT VT,
977 SDValue Operand, SDValue Subreg);
979 /// Get the specified node if it's already available, or else return NULL.
980 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs, ArrayRef<SDValue> Ops,
981 const SDNodeFlags *Flags = nullptr);
983 /// Creates a SDDbgValue node.
984 SDDbgValue *getDbgValue(MDNode *Var, MDNode *Expr, SDNode *N, unsigned R,
985 bool IsIndirect, uint64_t Off, DebugLoc DL,
989 SDDbgValue *getConstantDbgValue(MDNode *Var, MDNode *Expr, const Value *C,
990 uint64_t Off, DebugLoc DL, unsigned O);
993 SDDbgValue *getFrameIndexDbgValue(MDNode *Var, MDNode *Expr, unsigned FI,
994 uint64_t Off, DebugLoc DL, unsigned O);
996 /// Remove the specified node from the system. If any of its
997 /// operands then becomes dead, remove them as well. Inform UpdateListener
998 /// for each node deleted.
999 void RemoveDeadNode(SDNode *N);
1001 /// This method deletes the unreachable nodes in the
1002 /// given list, and any nodes that become unreachable as a result.
1003 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes);
1005 /// Modify anything using 'From' to use 'To' instead.
1006 /// This can cause recursive merging of nodes in the DAG. Use the first
1007 /// version if 'From' is known to have a single result, use the second
1008 /// if you have two nodes with identical results (or if 'To' has a superset
1009 /// of the results of 'From'), use the third otherwise.
1011 /// These methods all take an optional UpdateListener, which (if not null) is
1012 /// informed about nodes that are deleted and modified due to recursive
1013 /// changes in the dag.
1015 /// These functions only replace all existing uses. It's possible that as
1016 /// these replacements are being performed, CSE may cause the From node
1017 /// to be given new uses. These new uses of From are left in place, and
1018 /// not automatically transferred to To.
1020 void ReplaceAllUsesWith(SDValue From, SDValue Op);
1021 void ReplaceAllUsesWith(SDNode *From, SDNode *To);
1022 void ReplaceAllUsesWith(SDNode *From, const SDValue *To);
1024 /// Replace any uses of From with To, leaving
1025 /// uses of other values produced by From.Val alone.
1026 void ReplaceAllUsesOfValueWith(SDValue From, SDValue To);
1028 /// Like ReplaceAllUsesOfValueWith, but for multiple values at once.
1029 /// This correctly handles the case where
1030 /// there is an overlap between the From values and the To values.
1031 void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To,
1034 /// Topological-sort the AllNodes list and a
1035 /// assign a unique node id for each node in the DAG based on their
1036 /// topological order. Returns the number of nodes.
1037 unsigned AssignTopologicalOrder();
1039 /// Move node N in the AllNodes list to be immediately
1040 /// before the given iterator Position. This may be used to update the
1041 /// topological ordering when the list of nodes is modified.
1042 void RepositionNode(allnodes_iterator Position, SDNode *N) {
1043 AllNodes.insert(Position, AllNodes.remove(N));
1046 /// Returns true if the opcode is a commutative binary operation.
1047 static bool isCommutativeBinOp(unsigned Opcode) {
1048 // FIXME: This should get its info from the td file, so that we can include
1055 case ISD::SMUL_LOHI:
1056 case ISD::UMUL_LOHI:
1069 default: return false;
1073 /// Returns an APFloat semantics tag appropriate for the given type. If VT is
1074 /// a vector type, the element semantics are returned.
1075 static const fltSemantics &EVTToAPFloatSemantics(EVT VT) {
1076 switch (VT.getScalarType().getSimpleVT().SimpleTy) {
1077 default: llvm_unreachable("Unknown FP format");
1078 case MVT::f16: return APFloat::IEEEhalf;
1079 case MVT::f32: return APFloat::IEEEsingle;
1080 case MVT::f64: return APFloat::IEEEdouble;
1081 case MVT::f80: return APFloat::x87DoubleExtended;
1082 case MVT::f128: return APFloat::IEEEquad;
1083 case MVT::ppcf128: return APFloat::PPCDoubleDouble;
1087 /// Add a dbg_value SDNode. If SD is non-null that means the
1088 /// value is produced by SD.
1089 void AddDbgValue(SDDbgValue *DB, SDNode *SD, bool isParameter);
1091 /// Get the debug values which reference the given SDNode.
1092 ArrayRef<SDDbgValue*> GetDbgValues(const SDNode* SD) {
1093 return DbgInfo->getSDDbgValues(SD);
1096 /// Transfer SDDbgValues.
1097 void TransferDbgValues(SDValue From, SDValue To);
1099 /// Return true if there are any SDDbgValue nodes associated
1100 /// with this SelectionDAG.
1101 bool hasDebugValues() const { return !DbgInfo->empty(); }
1103 SDDbgInfo::DbgIterator DbgBegin() { return DbgInfo->DbgBegin(); }
1104 SDDbgInfo::DbgIterator DbgEnd() { return DbgInfo->DbgEnd(); }
1105 SDDbgInfo::DbgIterator ByvalParmDbgBegin() {
1106 return DbgInfo->ByvalParmDbgBegin();
1108 SDDbgInfo::DbgIterator ByvalParmDbgEnd() {
1109 return DbgInfo->ByvalParmDbgEnd();
1114 /// Create a stack temporary, suitable for holding the
1115 /// specified value type. If minAlign is specified, the slot size will have
1116 /// at least that alignment.
1117 SDValue CreateStackTemporary(EVT VT, unsigned minAlign = 1);
1119 /// Create a stack temporary suitable for holding
1120 /// either of the specified value types.
1121 SDValue CreateStackTemporary(EVT VT1, EVT VT2);
1123 SDValue FoldConstantArithmetic(unsigned Opcode, SDLoc DL, EVT VT,
1124 SDNode *Cst1, SDNode *Cst2);
1126 /// Constant fold a setcc to true or false.
1127 SDValue FoldSetCC(EVT VT, SDValue N1,
1128 SDValue N2, ISD::CondCode Cond, SDLoc dl);
1130 /// Return true if the sign bit of Op is known to be zero.
1131 /// We use this predicate to simplify operations downstream.
1132 bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const;
1134 /// Return true if 'Op & Mask' is known to be zero. We
1135 /// use this predicate to simplify operations downstream. Op and Mask are
1136 /// known to be the same type.
1137 bool MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth = 0)
1140 /// Determine which bits of Op are known to be either zero or one and return
1141 /// them in the KnownZero/KnownOne bitsets. Targets can implement the
1142 /// computeKnownBitsForTargetNode method in the TargetLowering class to allow
1143 /// target nodes to be understood.
1144 void computeKnownBits(SDValue Op, APInt &KnownZero, APInt &KnownOne,
1145 unsigned Depth = 0) const;
1147 /// Return the number of times the sign bit of the
1148 /// register is replicated into the other bits. We know that at least 1 bit
1149 /// is always equal to the sign bit (itself), but other cases can give us
1150 /// information. For example, immediately after an "SRA X, 2", we know that
1151 /// the top 3 bits are all equal to each other, so we return 3. Targets can
1152 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
1153 /// class to allow target nodes to be understood.
1154 unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const;
1156 /// Return true if the specified operand is an
1157 /// ISD::ADD with a ConstantSDNode on the right-hand side, or if it is an
1158 /// ISD::OR with a ConstantSDNode that is guaranteed to have the same
1159 /// semantics as an ADD. This handles the equivalence:
1160 /// X|Cst == X+Cst iff X&Cst = 0.
1161 bool isBaseWithConstantOffset(SDValue Op) const;
1163 /// Test whether the given SDValue is known to never be NaN.
1164 bool isKnownNeverNaN(SDValue Op) const;
1166 /// Test whether the given SDValue is known to never be
1167 /// positive or negative Zero.
1168 bool isKnownNeverZero(SDValue Op) const;
1170 /// Test whether two SDValues are known to compare equal. This
1171 /// is true if they are the same value, or if one is negative zero and the
1172 /// other positive zero.
1173 bool isEqualTo(SDValue A, SDValue B) const;
1175 /// Utility function used by legalize and lowering to
1176 /// "unroll" a vector operation by splitting out the scalars and operating
1177 /// on each element individually. If the ResNE is 0, fully unroll the vector
1178 /// op. If ResNE is less than the width of the vector op, unroll up to ResNE.
1179 /// If the ResNE is greater than the width of the vector op, unroll the
1180 /// vector op and fill the end of the resulting vector with UNDEFS.
1181 SDValue UnrollVectorOp(SDNode *N, unsigned ResNE = 0);
1183 /// Return true if LD is loading 'Bytes' bytes from a location that is 'Dist'
1184 /// units away from the location that the 'Base' load is loading from.
1185 bool isConsecutiveLoad(LoadSDNode *LD, LoadSDNode *Base,
1186 unsigned Bytes, int Dist) const;
1188 /// Infer alignment of a load / store address. Return 0 if
1189 /// it cannot be inferred.
1190 unsigned InferPtrAlignment(SDValue Ptr) const;
1192 /// Compute the VTs needed for the low/hi parts of a type
1193 /// which is split (or expanded) into two not necessarily identical pieces.
1194 std::pair<EVT, EVT> GetSplitDestVTs(const EVT &VT) const;
1196 /// Split the vector with EXTRACT_SUBVECTOR using the provides
1197 /// VTs and return the low/high part.
1198 std::pair<SDValue, SDValue> SplitVector(const SDValue &N, const SDLoc &DL,
1199 const EVT &LoVT, const EVT &HiVT);
1201 /// Split the vector with EXTRACT_SUBVECTOR and return the low/high part.
1202 std::pair<SDValue, SDValue> SplitVector(const SDValue &N, const SDLoc &DL) {
1204 std::tie(LoVT, HiVT) = GetSplitDestVTs(N.getValueType());
1205 return SplitVector(N, DL, LoVT, HiVT);
1208 /// Split the node's operand with EXTRACT_SUBVECTOR and
1209 /// return the low/high part.
1210 std::pair<SDValue, SDValue> SplitVectorOperand(const SDNode *N, unsigned OpNo)
1212 return SplitVector(N->getOperand(OpNo), SDLoc(N));
1215 /// Append the extracted elements from Start to Count out of the vector Op
1216 /// in Args. If Count is 0, all of the elements will be extracted.
1217 void ExtractVectorElements(SDValue Op, SmallVectorImpl<SDValue> &Args,
1218 unsigned Start = 0, unsigned Count = 0);
1220 unsigned getEVTAlignment(EVT MemoryVT) const;
1223 void InsertNode(SDNode *N);
1224 bool RemoveNodeFromCSEMaps(SDNode *N);
1225 void AddModifiedNodeToCSEMaps(SDNode *N);
1226 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos);
1227 SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2,
1229 SDNode *FindModifiedNodeSlot(SDNode *N, ArrayRef<SDValue> Ops,
1231 SDNode *UpdadeSDLocOnMergedSDNode(SDNode *N, SDLoc loc);
1233 void DeleteNodeNotInCSEMaps(SDNode *N);
1234 void DeallocateNode(SDNode *N);
1236 void allnodes_clear();
1238 SDNode *GetSDNodeWithFlags(unsigned Opcode, SDLoc DL, SDVTList VTs,
1239 ArrayRef<SDValue> Ops, const SDNodeFlags *Flags);
1241 /// List of non-single value types.
1242 FoldingSet<SDVTListNode> VTListMap;
1244 /// Maps to auto-CSE operations.
1245 std::vector<CondCodeSDNode*> CondCodeNodes;
1247 std::vector<SDNode*> ValueTypeNodes;
1248 std::map<EVT, SDNode*, EVT::compareRawBits> ExtendedValueTypeNodes;
1249 StringMap<SDNode*> ExternalSymbols;
1251 std::map<std::pair<std::string, unsigned char>,SDNode*> TargetExternalSymbols;
1254 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
1255 typedef SelectionDAG::allnodes_iterator nodes_iterator;
1256 static nodes_iterator nodes_begin(SelectionDAG *G) {
1257 return G->allnodes_begin();
1259 static nodes_iterator nodes_end(SelectionDAG *G) {
1260 return G->allnodes_end();
1264 } // end namespace llvm