LLVM  9.0.0svn
Instruction.h
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1 //===-- llvm/Instruction.h - Instruction class definition -------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file contains the declaration of the Instruction class, which is the
10 // base class for all of the LLVM instructions.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_IR_INSTRUCTION_H
15 #define LLVM_IR_INSTRUCTION_H
16 
17 #include "llvm/ADT/ArrayRef.h"
18 #include "llvm/ADT/None.h"
19 #include "llvm/ADT/StringRef.h"
20 #include "llvm/ADT/ilist_node.h"
21 #include "llvm/IR/DebugLoc.h"
23 #include "llvm/IR/User.h"
24 #include "llvm/IR/Value.h"
25 #include "llvm/Support/Casting.h"
26 #include <algorithm>
27 #include <cassert>
28 #include <cstdint>
29 #include <utility>
30 
31 namespace llvm {
32 
33 class BasicBlock;
34 class FastMathFlags;
35 class MDNode;
36 class Module;
37 struct AAMDNodes;
38 
39 template <> struct ilist_alloc_traits<Instruction> {
40  static inline void deleteNode(Instruction *V);
41 };
42 
43 class Instruction : public User,
44  public ilist_node_with_parent<Instruction, BasicBlock> {
45  BasicBlock *Parent;
46  DebugLoc DbgLoc; // 'dbg' Metadata cache.
47 
48  enum {
49  /// This is a bit stored in the SubClassData field which indicates whether
50  /// this instruction has metadata attached to it or not.
51  HasMetadataBit = 1 << 15
52  };
53 
54 protected:
55  ~Instruction(); // Use deleteValue() to delete a generic Instruction.
56 
57 public:
58  Instruction(const Instruction &) = delete;
59  Instruction &operator=(const Instruction &) = delete;
60 
61  /// Specialize the methods defined in Value, as we know that an instruction
62  /// can only be used by other instructions.
63  Instruction *user_back() { return cast<Instruction>(*user_begin());}
64  const Instruction *user_back() const { return cast<Instruction>(*user_begin());}
65 
66  inline const BasicBlock *getParent() const { return Parent; }
67  inline BasicBlock *getParent() { return Parent; }
68 
69  /// Return the module owning the function this instruction belongs to
70  /// or nullptr it the function does not have a module.
71  ///
72  /// Note: this is undefined behavior if the instruction does not have a
73  /// parent, or the parent basic block does not have a parent function.
74  const Module *getModule() const;
76  return const_cast<Module *>(
77  static_cast<const Instruction *>(this)->getModule());
78  }
79 
80  /// Return the function this instruction belongs to.
81  ///
82  /// Note: it is undefined behavior to call this on an instruction not
83  /// currently inserted into a function.
84  const Function *getFunction() const;
86  return const_cast<Function *>(
87  static_cast<const Instruction *>(this)->getFunction());
88  }
89 
90  /// This method unlinks 'this' from the containing basic block, but does not
91  /// delete it.
92  void removeFromParent();
93 
94  /// This method unlinks 'this' from the containing basic block and deletes it.
95  ///
96  /// \returns an iterator pointing to the element after the erased one
98 
99  /// Insert an unlinked instruction into a basic block immediately before
100  /// the specified instruction.
101  void insertBefore(Instruction *InsertPos);
102 
103  /// Insert an unlinked instruction into a basic block immediately after the
104  /// specified instruction.
105  void insertAfter(Instruction *InsertPos);
106 
107  /// Unlink this instruction from its current basic block and insert it into
108  /// the basic block that MovePos lives in, right before MovePos.
109  void moveBefore(Instruction *MovePos);
110 
111  /// Unlink this instruction and insert into BB before I.
112  ///
113  /// \pre I is a valid iterator into BB.
115 
116  /// Unlink this instruction from its current basic block and insert it into
117  /// the basic block that MovePos lives in, right after MovePos.
118  void moveAfter(Instruction *MovePos);
119 
120  //===--------------------------------------------------------------------===//
121  // Subclass classification.
122  //===--------------------------------------------------------------------===//
123 
124  /// Returns a member of one of the enums like Instruction::Add.
125  unsigned getOpcode() const { return getValueID() - InstructionVal; }
126 
127  const char *getOpcodeName() const { return getOpcodeName(getOpcode()); }
128  bool isTerminator() const { return isTerminator(getOpcode()); }
129  bool isUnaryOp() const { return isUnaryOp(getOpcode()); }
130  bool isBinaryOp() const { return isBinaryOp(getOpcode()); }
131  bool isIntDivRem() const { return isIntDivRem(getOpcode()); }
132  bool isShift() { return isShift(getOpcode()); }
133  bool isCast() const { return isCast(getOpcode()); }
134  bool isFuncletPad() const { return isFuncletPad(getOpcode()); }
135  bool isExceptionalTerminator() const {
136  return isExceptionalTerminator(getOpcode());
137  }
138  bool isIndirectTerminator() const {
139  return isIndirectTerminator(getOpcode());
140  }
141 
142  static const char* getOpcodeName(unsigned OpCode);
143 
144  static inline bool isTerminator(unsigned OpCode) {
145  return OpCode >= TermOpsBegin && OpCode < TermOpsEnd;
146  }
147 
148  static inline bool isUnaryOp(unsigned Opcode) {
149  return Opcode >= UnaryOpsBegin && Opcode < UnaryOpsEnd;
150  }
151  static inline bool isBinaryOp(unsigned Opcode) {
152  return Opcode >= BinaryOpsBegin && Opcode < BinaryOpsEnd;
153  }
154 
155  static inline bool isIntDivRem(unsigned Opcode) {
156  return Opcode == UDiv || Opcode == SDiv || Opcode == URem || Opcode == SRem;
157  }
158 
159  /// Determine if the Opcode is one of the shift instructions.
160  static inline bool isShift(unsigned Opcode) {
161  return Opcode >= Shl && Opcode <= AShr;
162  }
163 
164  /// Return true if this is a logical shift left or a logical shift right.
165  inline bool isLogicalShift() const {
166  return getOpcode() == Shl || getOpcode() == LShr;
167  }
168 
169  /// Return true if this is an arithmetic shift right.
170  inline bool isArithmeticShift() const {
171  return getOpcode() == AShr;
172  }
173 
174  /// Determine if the Opcode is and/or/xor.
175  static inline bool isBitwiseLogicOp(unsigned Opcode) {
176  return Opcode == And || Opcode == Or || Opcode == Xor;
177  }
178 
179  /// Return true if this is and/or/xor.
180  inline bool isBitwiseLogicOp() const {
181  return isBitwiseLogicOp(getOpcode());
182  }
183 
184  /// Determine if the OpCode is one of the CastInst instructions.
185  static inline bool isCast(unsigned OpCode) {
186  return OpCode >= CastOpsBegin && OpCode < CastOpsEnd;
187  }
188 
189  /// Determine if the OpCode is one of the FuncletPadInst instructions.
190  static inline bool isFuncletPad(unsigned OpCode) {
191  return OpCode >= FuncletPadOpsBegin && OpCode < FuncletPadOpsEnd;
192  }
193 
194  /// Returns true if the OpCode is a terminator related to exception handling.
195  static inline bool isExceptionalTerminator(unsigned OpCode) {
196  switch (OpCode) {
197  case Instruction::CatchSwitch:
198  case Instruction::CatchRet:
199  case Instruction::CleanupRet:
200  case Instruction::Invoke:
201  case Instruction::Resume:
202  return true;
203  default:
204  return false;
205  }
206  }
207 
208  /// Returns true if the OpCode is a terminator with indirect targets.
209  static inline bool isIndirectTerminator(unsigned OpCode) {
210  switch (OpCode) {
211  case Instruction::IndirectBr:
212  case Instruction::CallBr:
213  return true;
214  default:
215  return false;
216  }
217  }
218 
219  //===--------------------------------------------------------------------===//
220  // Metadata manipulation.
221  //===--------------------------------------------------------------------===//
222 
223  /// Return true if this instruction has any metadata attached to it.
224  bool hasMetadata() const { return DbgLoc || hasMetadataHashEntry(); }
225 
226  /// Return true if this instruction has metadata attached to it other than a
227  /// debug location.
229  return hasMetadataHashEntry();
230  }
231 
232  /// Get the metadata of given kind attached to this Instruction.
233  /// If the metadata is not found then return null.
234  MDNode *getMetadata(unsigned KindID) const {
235  if (!hasMetadata()) return nullptr;
236  return getMetadataImpl(KindID);
237  }
238 
239  /// Get the metadata of given kind attached to this Instruction.
240  /// If the metadata is not found then return null.
242  if (!hasMetadata()) return nullptr;
243  return getMetadataImpl(Kind);
244  }
245 
246  /// Get all metadata attached to this Instruction. The first element of each
247  /// pair returned is the KindID, the second element is the metadata value.
248  /// This list is returned sorted by the KindID.
249  void
250  getAllMetadata(SmallVectorImpl<std::pair<unsigned, MDNode *>> &MDs) const {
251  if (hasMetadata())
252  getAllMetadataImpl(MDs);
253  }
254 
255  /// This does the same thing as getAllMetadata, except that it filters out the
256  /// debug location.
258  SmallVectorImpl<std::pair<unsigned, MDNode *>> &MDs) const {
260  getAllMetadataOtherThanDebugLocImpl(MDs);
261  }
262 
263  /// Fills the AAMDNodes structure with AA metadata from this instruction.
264  /// When Merge is true, the existing AA metadata is merged with that from this
265  /// instruction providing the most-general result.
266  void getAAMetadata(AAMDNodes &N, bool Merge = false) const;
267 
268  /// Set the metadata of the specified kind to the specified node. This updates
269  /// or replaces metadata if already present, or removes it if Node is null.
270  void setMetadata(unsigned KindID, MDNode *Node);
271  void setMetadata(StringRef Kind, MDNode *Node);
272 
273  /// Copy metadata from \p SrcInst to this instruction. \p WL, if not empty,
274  /// specifies the list of meta data that needs to be copied. If \p WL is
275  /// empty, all meta data will be copied.
276  void copyMetadata(const Instruction &SrcInst,
278 
279  /// If the instruction has "branch_weights" MD_prof metadata and the MDNode
280  /// has three operands (including name string), swap the order of the
281  /// metadata.
282  void swapProfMetadata();
283 
284  /// Drop all unknown metadata except for debug locations.
285  /// @{
286  /// Passes are required to drop metadata they don't understand. This is a
287  /// convenience method for passes to do so.
288  void dropUnknownNonDebugMetadata(ArrayRef<unsigned> KnownIDs);
290  return dropUnknownNonDebugMetadata(None);
291  }
292  void dropUnknownNonDebugMetadata(unsigned ID1) {
293  return dropUnknownNonDebugMetadata(makeArrayRef(ID1));
294  }
295  void dropUnknownNonDebugMetadata(unsigned ID1, unsigned ID2) {
296  unsigned IDs[] = {ID1, ID2};
297  return dropUnknownNonDebugMetadata(IDs);
298  }
299  /// @}
300 
301  /// Sets the metadata on this instruction from the AAMDNodes structure.
302  void setAAMetadata(const AAMDNodes &N);
303 
304  /// Retrieve the raw weight values of a conditional branch or select.
305  /// Returns true on success with profile weights filled in.
306  /// Returns false if no metadata or invalid metadata was found.
307  bool extractProfMetadata(uint64_t &TrueVal, uint64_t &FalseVal) const;
308 
309  /// Retrieve total raw weight values of a branch.
310  /// Returns true on success with profile total weights filled in.
311  /// Returns false if no metadata was found.
312  bool extractProfTotalWeight(uint64_t &TotalVal) const;
313 
314  /// Updates branch_weights metadata by scaling it by \p S / \p T.
315  void updateProfWeight(uint64_t S, uint64_t T);
316 
317  /// Sets the branch_weights metadata to \p W for CallInst.
318  void setProfWeight(uint64_t W);
319 
320  /// Set the debug location information for this instruction.
321  void setDebugLoc(DebugLoc Loc) { DbgLoc = std::move(Loc); }
322 
323  /// Return the debug location for this node as a DebugLoc.
324  const DebugLoc &getDebugLoc() const { return DbgLoc; }
325 
326  /// Set or clear the nuw flag on this instruction, which must be an operator
327  /// which supports this flag. See LangRef.html for the meaning of this flag.
328  void setHasNoUnsignedWrap(bool b = true);
329 
330  /// Set or clear the nsw flag on this instruction, which must be an operator
331  /// which supports this flag. See LangRef.html for the meaning of this flag.
332  void setHasNoSignedWrap(bool b = true);
333 
334  /// Set or clear the exact flag on this instruction, which must be an operator
335  /// which supports this flag. See LangRef.html for the meaning of this flag.
336  void setIsExact(bool b = true);
337 
338  /// Determine whether the no unsigned wrap flag is set.
339  bool hasNoUnsignedWrap() const;
340 
341  /// Determine whether the no signed wrap flag is set.
342  bool hasNoSignedWrap() const;
343 
344  /// Drops flags that may cause this instruction to evaluate to poison despite
345  /// having non-poison inputs.
346  void dropPoisonGeneratingFlags();
347 
348  /// Determine whether the exact flag is set.
349  bool isExact() const;
350 
351  /// Set or clear all fast-math-flags on this instruction, which must be an
352  /// operator which supports this flag. See LangRef.html for the meaning of
353  /// this flag.
354  void setFast(bool B);
355 
356  /// Set or clear the reassociation flag on this instruction, which must be
357  /// an operator which supports this flag. See LangRef.html for the meaning of
358  /// this flag.
359  void setHasAllowReassoc(bool B);
360 
361  /// Set or clear the no-nans flag on this instruction, which must be an
362  /// operator which supports this flag. See LangRef.html for the meaning of
363  /// this flag.
364  void setHasNoNaNs(bool B);
365 
366  /// Set or clear the no-infs flag on this instruction, which must be an
367  /// operator which supports this flag. See LangRef.html for the meaning of
368  /// this flag.
369  void setHasNoInfs(bool B);
370 
371  /// Set or clear the no-signed-zeros flag on this instruction, which must be
372  /// an operator which supports this flag. See LangRef.html for the meaning of
373  /// this flag.
374  void setHasNoSignedZeros(bool B);
375 
376  /// Set or clear the allow-reciprocal flag on this instruction, which must be
377  /// an operator which supports this flag. See LangRef.html for the meaning of
378  /// this flag.
379  void setHasAllowReciprocal(bool B);
380 
381  /// Set or clear the approximate-math-functions flag on this instruction,
382  /// which must be an operator which supports this flag. See LangRef.html for
383  /// the meaning of this flag.
384  void setHasApproxFunc(bool B);
385 
386  /// Convenience function for setting multiple fast-math flags on this
387  /// instruction, which must be an operator which supports these flags. See
388  /// LangRef.html for the meaning of these flags.
389  void setFastMathFlags(FastMathFlags FMF);
390 
391  /// Convenience function for transferring all fast-math flag values to this
392  /// instruction, which must be an operator which supports these flags. See
393  /// LangRef.html for the meaning of these flags.
394  void copyFastMathFlags(FastMathFlags FMF);
395 
396  /// Determine whether all fast-math-flags are set.
397  bool isFast() const;
398 
399  /// Determine whether the allow-reassociation flag is set.
400  bool hasAllowReassoc() const;
401 
402  /// Determine whether the no-NaNs flag is set.
403  bool hasNoNaNs() const;
404 
405  /// Determine whether the no-infs flag is set.
406  bool hasNoInfs() const;
407 
408  /// Determine whether the no-signed-zeros flag is set.
409  bool hasNoSignedZeros() const;
410 
411  /// Determine whether the allow-reciprocal flag is set.
412  bool hasAllowReciprocal() const;
413 
414  /// Determine whether the allow-contract flag is set.
415  bool hasAllowContract() const;
416 
417  /// Determine whether the approximate-math-functions flag is set.
418  bool hasApproxFunc() const;
419 
420  /// Convenience function for getting all the fast-math flags, which must be an
421  /// operator which supports these flags. See LangRef.html for the meaning of
422  /// these flags.
423  FastMathFlags getFastMathFlags() const;
424 
425  /// Copy I's fast-math flags
426  void copyFastMathFlags(const Instruction *I);
427 
428  /// Convenience method to copy supported exact, fast-math, and (optionally)
429  /// wrapping flags from V to this instruction.
430  void copyIRFlags(const Value *V, bool IncludeWrapFlags = true);
431 
432  /// Logical 'and' of any supported wrapping, exact, and fast-math flags of
433  /// V and this instruction.
434  void andIRFlags(const Value *V);
435 
436  /// Merge 2 debug locations and apply it to the Instruction. If the
437  /// instruction is a CallIns, we need to traverse the inline chain to find
438  /// the common scope. This is not efficient for N-way merging as each time
439  /// you merge 2 iterations, you need to rebuild the hashmap to find the
440  /// common scope. However, we still choose this API because:
441  /// 1) Simplicity: it takes 2 locations instead of a list of locations.
442  /// 2) In worst case, it increases the complexity from O(N*I) to
443  /// O(2*N*I), where N is # of Instructions to merge, and I is the
444  /// maximum level of inline stack. So it is still linear.
445  /// 3) Merging of call instructions should be extremely rare in real
446  /// applications, thus the N-way merging should be in code path.
447  /// The DebugLoc attached to this instruction will be overwritten by the
448  /// merged DebugLoc.
449  void applyMergedLocation(const DILocation *LocA, const DILocation *LocB);
450 
451 private:
452  /// Return true if we have an entry in the on-the-side metadata hash.
453  bool hasMetadataHashEntry() const {
454  return (getSubclassDataFromValue() & HasMetadataBit) != 0;
455  }
456 
457  // These are all implemented in Metadata.cpp.
458  MDNode *getMetadataImpl(unsigned KindID) const;
459  MDNode *getMetadataImpl(StringRef Kind) const;
460  void
461  getAllMetadataImpl(SmallVectorImpl<std::pair<unsigned, MDNode *>> &) const;
462  void getAllMetadataOtherThanDebugLocImpl(
463  SmallVectorImpl<std::pair<unsigned, MDNode *>> &) const;
464  /// Clear all hashtable-based metadata from this instruction.
465  void clearMetadataHashEntries();
466 
467 public:
468  //===--------------------------------------------------------------------===//
469  // Predicates and helper methods.
470  //===--------------------------------------------------------------------===//
471 
472  /// Return true if the instruction is associative:
473  ///
474  /// Associative operators satisfy: x op (y op z) === (x op y) op z
475  ///
476  /// In LLVM, the Add, Mul, And, Or, and Xor operators are associative.
477  ///
478  bool isAssociative() const LLVM_READONLY;
479  static bool isAssociative(unsigned Opcode) {
480  return Opcode == And || Opcode == Or || Opcode == Xor ||
481  Opcode == Add || Opcode == Mul;
482  }
483 
484  /// Return true if the instruction is commutative:
485  ///
486  /// Commutative operators satisfy: (x op y) === (y op x)
487  ///
488  /// In LLVM, these are the commutative operators, plus SetEQ and SetNE, when
489  /// applied to any type.
490  ///
491  bool isCommutative() const { return isCommutative(getOpcode()); }
492  static bool isCommutative(unsigned Opcode) {
493  switch (Opcode) {
494  case Add: case FAdd:
495  case Mul: case FMul:
496  case And: case Or: case Xor:
497  return true;
498  default:
499  return false;
500  }
501  }
502 
503  /// Return true if the instruction is idempotent:
504  ///
505  /// Idempotent operators satisfy: x op x === x
506  ///
507  /// In LLVM, the And and Or operators are idempotent.
508  ///
509  bool isIdempotent() const { return isIdempotent(getOpcode()); }
510  static bool isIdempotent(unsigned Opcode) {
511  return Opcode == And || Opcode == Or;
512  }
513 
514  /// Return true if the instruction is nilpotent:
515  ///
516  /// Nilpotent operators satisfy: x op x === Id,
517  ///
518  /// where Id is the identity for the operator, i.e. a constant such that
519  /// x op Id === x and Id op x === x for all x.
520  ///
521  /// In LLVM, the Xor operator is nilpotent.
522  ///
523  bool isNilpotent() const { return isNilpotent(getOpcode()); }
524  static bool isNilpotent(unsigned Opcode) {
525  return Opcode == Xor;
526  }
527 
528  /// Return true if this instruction may modify memory.
529  bool mayWriteToMemory() const;
530 
531  /// Return true if this instruction may read memory.
532  bool mayReadFromMemory() const;
533 
534  /// Return true if this instruction may read or write memory.
535  bool mayReadOrWriteMemory() const {
536  return mayReadFromMemory() || mayWriteToMemory();
537  }
538 
539  /// Return true if this instruction has an AtomicOrdering of unordered or
540  /// higher.
541  bool isAtomic() const;
542 
543  /// Return true if this atomic instruction loads from memory.
544  bool hasAtomicLoad() const;
545 
546  /// Return true if this atomic instruction stores to memory.
547  bool hasAtomicStore() const;
548 
549  /// Return true if this instruction may throw an exception.
550  bool mayThrow() const;
551 
552  /// Return true if this instruction behaves like a memory fence: it can load
553  /// or store to memory location without being given a memory location.
554  bool isFenceLike() const {
555  switch (getOpcode()) {
556  default:
557  return false;
558  // This list should be kept in sync with the list in mayWriteToMemory for
559  // all opcodes which don't have a memory location.
560  case Instruction::Fence:
561  case Instruction::CatchPad:
562  case Instruction::CatchRet:
563  case Instruction::Call:
564  case Instruction::Invoke:
565  return true;
566  }
567  }
568 
569  /// Return true if the instruction may have side effects.
570  ///
571  /// Note that this does not consider malloc and alloca to have side
572  /// effects because the newly allocated memory is completely invisible to
573  /// instructions which don't use the returned value. For cases where this
574  /// matters, isSafeToSpeculativelyExecute may be more appropriate.
575  bool mayHaveSideEffects() const { return mayWriteToMemory() || mayThrow(); }
576 
577  /// Return true if the instruction can be removed if the result is unused.
578  ///
579  /// When constant folding some instructions cannot be removed even if their
580  /// results are unused. Specifically terminator instructions and calls that
581  /// may have side effects cannot be removed without semantically changing the
582  /// generated program.
583  bool isSafeToRemove() const;
584 
585  /// Return true if the instruction is a variety of EH-block.
586  bool isEHPad() const {
587  switch (getOpcode()) {
588  case Instruction::CatchSwitch:
589  case Instruction::CatchPad:
590  case Instruction::CleanupPad:
591  case Instruction::LandingPad:
592  return true;
593  default:
594  return false;
595  }
596  }
597 
598  /// Return true if the instruction is a llvm.lifetime.start or
599  /// llvm.lifetime.end marker.
600  bool isLifetimeStartOrEnd() const;
601 
602  /// Return a pointer to the next non-debug instruction in the same basic
603  /// block as 'this', or nullptr if no such instruction exists.
604  const Instruction *getNextNonDebugInstruction() const;
606  return const_cast<Instruction *>(
607  static_cast<const Instruction *>(this)->getNextNonDebugInstruction());
608  }
609 
610  /// Return a pointer to the previous non-debug instruction in the same basic
611  /// block as 'this', or nullptr if no such instruction exists.
612  const Instruction *getPrevNonDebugInstruction() const;
614  return const_cast<Instruction *>(
615  static_cast<const Instruction *>(this)->getPrevNonDebugInstruction());
616  }
617 
618  /// Create a copy of 'this' instruction that is identical in all ways except
619  /// the following:
620  /// * The instruction has no parent
621  /// * The instruction has no name
622  ///
623  Instruction *clone() const;
624 
625  /// Return true if the specified instruction is exactly identical to the
626  /// current one. This means that all operands match and any extra information
627  /// (e.g. load is volatile) agree.
628  bool isIdenticalTo(const Instruction *I) const;
629 
630  /// This is like isIdenticalTo, except that it ignores the
631  /// SubclassOptionalData flags, which may specify conditions under which the
632  /// instruction's result is undefined.
633  bool isIdenticalToWhenDefined(const Instruction *I) const;
634 
635  /// When checking for operation equivalence (using isSameOperationAs) it is
636  /// sometimes useful to ignore certain attributes.
638  /// Check for equivalence ignoring load/store alignment.
639  CompareIgnoringAlignment = 1<<0,
640  /// Check for equivalence treating a type and a vector of that type
641  /// as equivalent.
642  CompareUsingScalarTypes = 1<<1
643  };
644 
645  /// This function determines if the specified instruction executes the same
646  /// operation as the current one. This means that the opcodes, type, operand
647  /// types and any other factors affecting the operation must be the same. This
648  /// is similar to isIdenticalTo except the operands themselves don't have to
649  /// be identical.
650  /// @returns true if the specified instruction is the same operation as
651  /// the current one.
652  /// Determine if one instruction is the same operation as another.
653  bool isSameOperationAs(const Instruction *I, unsigned flags = 0) const;
654 
655  /// Return true if there are any uses of this instruction in blocks other than
656  /// the specified block. Note that PHI nodes are considered to evaluate their
657  /// operands in the corresponding predecessor block.
658  bool isUsedOutsideOfBlock(const BasicBlock *BB) const;
659 
660  /// Return the number of successors that this instruction has. The instruction
661  /// must be a terminator.
662  unsigned getNumSuccessors() const;
663 
664  /// Return the specified successor. This instruction must be a terminator.
665  BasicBlock *getSuccessor(unsigned Idx) const;
666 
667  /// Update the specified successor to point at the provided block. This
668  /// instruction must be a terminator.
669  void setSuccessor(unsigned Idx, BasicBlock *BB);
670 
671  /// Methods for support type inquiry through isa, cast, and dyn_cast:
672  static bool classof(const Value *V) {
673  return V->getValueID() >= Value::InstructionVal;
674  }
675 
676  //----------------------------------------------------------------------
677  // Exported enumerations.
678  //
679  enum TermOps { // These terminate basic blocks
680 #define FIRST_TERM_INST(N) TermOpsBegin = N,
681 #define HANDLE_TERM_INST(N, OPC, CLASS) OPC = N,
682 #define LAST_TERM_INST(N) TermOpsEnd = N+1
683 #include "llvm/IR/Instruction.def"
684  };
685 
686  enum UnaryOps {
687 #define FIRST_UNARY_INST(N) UnaryOpsBegin = N,
688 #define HANDLE_UNARY_INST(N, OPC, CLASS) OPC = N,
689 #define LAST_UNARY_INST(N) UnaryOpsEnd = N+1
690 #include "llvm/IR/Instruction.def"
691  };
692 
693  enum BinaryOps {
694 #define FIRST_BINARY_INST(N) BinaryOpsBegin = N,
695 #define HANDLE_BINARY_INST(N, OPC, CLASS) OPC = N,
696 #define LAST_BINARY_INST(N) BinaryOpsEnd = N+1
697 #include "llvm/IR/Instruction.def"
698  };
699 
700  enum MemoryOps {
701 #define FIRST_MEMORY_INST(N) MemoryOpsBegin = N,
702 #define HANDLE_MEMORY_INST(N, OPC, CLASS) OPC = N,
703 #define LAST_MEMORY_INST(N) MemoryOpsEnd = N+1
704 #include "llvm/IR/Instruction.def"
705  };
706 
707  enum CastOps {
708 #define FIRST_CAST_INST(N) CastOpsBegin = N,
709 #define HANDLE_CAST_INST(N, OPC, CLASS) OPC = N,
710 #define LAST_CAST_INST(N) CastOpsEnd = N+1
711 #include "llvm/IR/Instruction.def"
712  };
713 
715 #define FIRST_FUNCLETPAD_INST(N) FuncletPadOpsBegin = N,
716 #define HANDLE_FUNCLETPAD_INST(N, OPC, CLASS) OPC = N,
717 #define LAST_FUNCLETPAD_INST(N) FuncletPadOpsEnd = N+1
718 #include "llvm/IR/Instruction.def"
719  };
720 
721  enum OtherOps {
722 #define FIRST_OTHER_INST(N) OtherOpsBegin = N,
723 #define HANDLE_OTHER_INST(N, OPC, CLASS) OPC = N,
724 #define LAST_OTHER_INST(N) OtherOpsEnd = N+1
725 #include "llvm/IR/Instruction.def"
726  };
727 
728 private:
730 
731  // Shadow Value::setValueSubclassData with a private forwarding method so that
732  // subclasses cannot accidentally use it.
733  void setValueSubclassData(unsigned short D) {
735  }
736 
737  unsigned short getSubclassDataFromValue() const {
739  }
740 
741  void setHasMetadataHashEntry(bool V) {
742  setValueSubclassData((getSubclassDataFromValue() & ~HasMetadataBit) |
743  (V ? HasMetadataBit : 0));
744  }
745 
746  void setParent(BasicBlock *P);
747 
748 protected:
749  // Instruction subclasses can stick up to 15 bits of stuff into the
750  // SubclassData field of instruction with these members.
751 
752  // Verify that only the low 15 bits are used.
753  void setInstructionSubclassData(unsigned short D) {
754  assert((D & HasMetadataBit) == 0 && "Out of range value put into field");
755  setValueSubclassData((getSubclassDataFromValue() & HasMetadataBit) | D);
756  }
757 
759  return getSubclassDataFromValue() & ~HasMetadataBit;
760  }
761 
762  Instruction(Type *Ty, unsigned iType, Use *Ops, unsigned NumOps,
763  Instruction *InsertBefore = nullptr);
764  Instruction(Type *Ty, unsigned iType, Use *Ops, unsigned NumOps,
765  BasicBlock *InsertAtEnd);
766 
767 private:
768  /// Create a copy of this instruction.
769  Instruction *cloneImpl() const;
770 };
771 
773  V->deleteValue();
774 }
775 
776 } // end namespace llvm
777 
778 #endif // LLVM_IR_INSTRUCTION_H
Function * getFunction()
Definition: Instruction.h:85
void getAllMetadataOtherThanDebugLoc(SmallVectorImpl< std::pair< unsigned, MDNode *>> &MDs) const
This does the same thing as getAllMetadata, except that it filters out the debug location.
Definition: Instruction.h:257
unsigned short getSubclassDataFromValue() const
Definition: Value.h:654
unsigned getValueID() const
Return an ID for the concrete type of this object.
Definition: Value.h:463
bool isFuncletPad() const
Definition: Instruction.h:134
bool isFenceLike() const
Return true if this instruction behaves like a memory fence: it can load or store to memory location ...
Definition: Instruction.h:554
This class represents lattice values for constants.
Definition: AllocatorList.h:23
unsigned getSubclassDataFromInstruction() const
Definition: Instruction.h:758
Various leaf nodes.
Definition: ISDOpcodes.h:59
bool hasMetadataOtherThanDebugLoc() const
Return true if this instruction has metadata attached to it other than a debug location.
Definition: Instruction.h:228
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:64
bool isIdempotent() const
Return true if the instruction is idempotent:
Definition: Instruction.h:509
bool mayThrow(const MachineInstr &MI)
MDNode * getMetadata(StringRef Kind) const
Get the metadata of given kind attached to this Instruction.
Definition: Instruction.h:241
bool isTerminator() const
Definition: Instruction.h:128
void deleteValue()
Delete a pointer to a generic Value.
Definition: Value.cpp:98
A debug info location.
Definition: DebugLoc.h:33
Metadata node.
Definition: Metadata.h:863
bool isArithmeticShift() const
Return true if this is an arithmetic shift right.
Definition: Instruction.h:170
static bool isBitwiseLogicOp(unsigned Opcode)
Determine if the Opcode is and/or/xor.
Definition: Instruction.h:175
static bool isShift(unsigned Opcode)
Determine if the Opcode is one of the shift instructions.
Definition: Instruction.h:160
static bool isCommutative(unsigned Opcode)
Definition: Instruction.h:492
ArrayRef< T > makeArrayRef(const T &OneElt)
Construct an ArrayRef from a single element.
Definition: ArrayRef.h:450
bool isNilpotent() const
Return true if the instruction is nilpotent:
Definition: Instruction.h:523
A Use represents the edge between a Value definition and its users.
Definition: Use.h:55
static Optional< unsigned > getOpcode(ArrayRef< VPValue *> Values)
Returns the opcode of Values or ~0 if they do not all agree.
Definition: VPlanSLP.cpp:196
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: APFloat.h:41
static bool isIndirectTerminator(unsigned OpCode)
Returns true if the OpCode is a terminator with indirect targets.
Definition: Instruction.h:209
bool hasMetadata() const
Return true if this instruction has any metadata attached to it.
Definition: Instruction.h:224
void dropUnknownNonDebugMetadata(unsigned ID1)
Definition: Instruction.h:292
OperationEquivalenceFlags
When checking for operation equivalence (using isSameOperationAs) it is sometimes useful to ignore ce...
Definition: Instruction.h:637
bool isBitwiseLogicOp() const
Return true if this is and/or/xor.
Definition: Instruction.h:180
void dropUnknownNonDebugMetadata()
Definition: Instruction.h:289
static bool isBinaryOp(unsigned Opcode)
Definition: Instruction.h:151
MDNode * getMetadata(unsigned KindID) const
Get the metadata of given kind attached to this Instruction.
Definition: Instruction.h:234
unsigned getOpcode() const
Returns a member of one of the enums like Instruction::Add.
Definition: Instruction.h:125
void setInstructionSubclassData(unsigned short D)
Definition: Instruction.h:753
Instruction * getNextNonDebugInstruction()
Definition: Instruction.h:605
static bool hasMetadataOtherThanDebugLoc(const GlobalVariable *GV)
static Function * getFunction(Constant *C)
Definition: Evaluator.cpp:220
Debug location.
BasicBlock * getParent()
Definition: Instruction.h:67
static bool isTerminator(unsigned OpCode)
Definition: Instruction.h:144
Use delete by default for iplist and ilist.
Definition: ilist.h:40
#define P(N)
An ilist node that can access its parent list.
Definition: ilist_node.h:256
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
void setDebugLoc(DebugLoc Loc)
Set the debug location information for this instruction.
Definition: Instruction.h:321
LLVM Basic Block Representation.
Definition: BasicBlock.h:57
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:45
const char * getOpcodeName() const
Definition: Instruction.h:127
bool mayHaveSideEffects() const
Return true if the instruction may have side effects.
Definition: Instruction.h:575
static bool isUnaryOp(unsigned Opcode)
Definition: Instruction.h:148
static bool classof(const Value *V)
Methods for support type inquiry through isa, cast, and dyn_cast:
Definition: Instruction.h:672
bool isBinaryOp() const
Definition: Instruction.h:130
R600 Clause Merge
bool isExceptionalTerminator() const
Definition: Instruction.h:135
bool isCast() const
Definition: Instruction.h:133
static bool isAtomic(Instruction *I)
C setMetadata(LLVMContext::MD_range, MDNode::get(Context, LowAndHigh))
Module * getModule()
Definition: Instruction.h:75
Instruction * user_back()
Specialize the methods defined in Value, as we know that an instruction can only be used by other ins...
Definition: Instruction.h:63
A collection of metadata nodes that might be associated with a memory access used by the alias-analys...
Definition: Metadata.h:643
static bool isCast(unsigned OpCode)
Determine if the OpCode is one of the CastInst instructions.
Definition: Instruction.h:185
void dropUnknownNonDebugMetadata(unsigned ID1, unsigned ID2)
Definition: Instruction.h:295
static GCRegistry::Add< StatepointGC > D("statepoint-example", "an example strategy for statepoint")
static void deleteNode(NodeTy *V)
Definition: ilist.h:41
bool isCommutative() const
Return true if the instruction is commutative:
Definition: Instruction.h:491
void setValueSubclassData(unsigned short D)
Definition: Value.h:655
void getAllMetadata(SmallVectorImpl< std::pair< unsigned, MDNode *>> &MDs) const
Get all metadata attached to this Instruction.
Definition: Instruction.h:250
static bool isExceptionalTerminator(unsigned OpCode)
Returns true if the OpCode is a terminator related to exception handling.
Definition: Instruction.h:195
const Instruction * user_back() const
Definition: Instruction.h:64
List that automatically updates parent links and symbol tables.
const DebugLoc & getDebugLoc() const
Return the debug location for this node as a DebugLoc.
Definition: Instruction.h:324
static bool isNilpotent(unsigned Opcode)
Definition: Instruction.h:524
#define I(x, y, z)
Definition: MD5.cpp:58
#define N
#define LLVM_READONLY
Definition: Compiler.h:183
bool isLogicalShift() const
Return true if this is a logical shift left or a logical shift right.
Definition: Instruction.h:165
static bool isFuncletPad(unsigned OpCode)
Determine if the OpCode is one of the FuncletPadInst instructions.
Definition: Instruction.h:190
bool isIndirectTerminator() const
Definition: Instruction.h:138
const unsigned Kind
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
LLVM Value Representation.
Definition: Value.h:72
static bool isIntDivRem(unsigned Opcode)
Definition: Instruction.h:155
Instruction * getPrevNonDebugInstruction()
Definition: Instruction.h:613
bool isEHPad() const
Return true if the instruction is a variety of EH-block.
Definition: Instruction.h:586
Convenience struct for specifying and reasoning about fast-math flags.
Definition: Operator.h:159
bool isIntDivRem() const
Definition: Instruction.h:131
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
static bool isIdempotent(unsigned Opcode)
Definition: Instruction.h:510
static bool isAssociative(const COFFSection &Section)
bool isUnaryOp() const
Definition: Instruction.h:129
static bool isAssociative(unsigned Opcode)
Definition: Instruction.h:479
const BasicBlock * getParent() const
Definition: Instruction.h:66
bool mayReadOrWriteMemory() const
Return true if this instruction may read or write memory.
Definition: Instruction.h:535