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Value.h
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1 //===- llvm/Value.h - Definition of the Value class -------------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file declares the Value class.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_IR_VALUE_H
15 #define LLVM_IR_VALUE_H
16 
17 #include "llvm-c/Types.h"
19 #include "llvm/IR/Use.h"
21 #include "llvm/Support/Casting.h"
22 #include <cassert>
23 #include <iterator>
24 #include <memory>
25 
26 namespace llvm {
27 
28 class APInt;
29 class Argument;
30 class BasicBlock;
31 class Constant;
32 class ConstantData;
33 class ConstantAggregate;
34 class DataLayout;
35 class Function;
36 class GlobalAlias;
37 class GlobalIFunc;
38 class GlobalIndirectSymbol;
39 class GlobalObject;
40 class GlobalValue;
41 class GlobalVariable;
42 class InlineAsm;
43 class Instruction;
44 class LLVMContext;
45 class Module;
46 class ModuleSlotTracker;
47 class raw_ostream;
48 template<typename ValueTy> class StringMapEntry;
49 class StringRef;
50 class Twine;
51 class Type;
52 class User;
53 
55 
56 //===----------------------------------------------------------------------===//
57 // Value Class
58 //===----------------------------------------------------------------------===//
59 
60 /// \brief LLVM Value Representation
61 ///
62 /// This is a very important LLVM class. It is the base class of all values
63 /// computed by a program that may be used as operands to other values. Value is
64 /// the super class of other important classes such as Instruction and Function.
65 /// All Values have a Type. Type is not a subclass of Value. Some values can
66 /// have a name and they belong to some Module. Setting the name on the Value
67 /// automatically updates the module's symbol table.
68 ///
69 /// Every value has a "use list" that keeps track of which other Values are
70 /// using this Value. A Value can also have an arbitrary number of ValueHandle
71 /// objects that watch it and listen to RAUW and Destroy events. See
72 /// llvm/IR/ValueHandle.h for details.
73 class Value {
74  // The least-significant bit of the first word of Value *must* be zero:
75  // http://www.llvm.org/docs/ProgrammersManual.html#the-waymarking-algorithm
76  Type *VTy;
77  Use *UseList;
78 
79  friend class ValueAsMetadata; // Allow access to IsUsedByMD.
80  friend class ValueHandleBase;
81 
82  const unsigned char SubclassID; // Subclass identifier (for isa/dyn_cast)
83  unsigned char HasValueHandle : 1; // Has a ValueHandle pointing to this?
84 
85 protected:
86  /// \brief Hold subclass data that can be dropped.
87  ///
88  /// This member is similar to SubclassData, however it is for holding
89  /// information which may be used to aid optimization, but which may be
90  /// cleared to zero without affecting conservative interpretation.
91  unsigned char SubclassOptionalData : 7;
92 
93 private:
94  /// \brief Hold arbitrary subclass data.
95  ///
96  /// This member is defined by this class, but is not used for anything.
97  /// Subclasses can use it to hold whatever state they find useful. This
98  /// field is initialized to zero by the ctor.
99  unsigned short SubclassData;
100 
101 protected:
102  /// \brief The number of operands in the subclass.
103  ///
104  /// This member is defined by this class, but not used for anything.
105  /// Subclasses can use it to store their number of operands, if they have
106  /// any.
107  ///
108  /// This is stored here to save space in User on 64-bit hosts. Since most
109  /// instances of Value have operands, 32-bit hosts aren't significantly
110  /// affected.
111  ///
112  /// Note, this should *NOT* be used directly by any class other than User.
113  /// User uses this value to find the Use list.
114  enum : unsigned { NumUserOperandsBits = 28 };
116 
117  // Use the same type as the bitfield above so that MSVC will pack them.
118  unsigned IsUsedByMD : 1;
119  unsigned HasName : 1;
120  unsigned HasHungOffUses : 1;
121  unsigned HasDescriptor : 1;
122 
123 private:
124  template <typename UseT> // UseT == 'Use' or 'const Use'
125  class use_iterator_impl
126  : public std::iterator<std::forward_iterator_tag, UseT *> {
127  friend class Value;
128 
129  UseT *U;
130 
131  explicit use_iterator_impl(UseT *u) : U(u) {}
132 
133  public:
134  use_iterator_impl() : U() {}
135 
136  bool operator==(const use_iterator_impl &x) const { return U == x.U; }
137  bool operator!=(const use_iterator_impl &x) const { return !operator==(x); }
138 
139  use_iterator_impl &operator++() { // Preincrement
140  assert(U && "Cannot increment end iterator!");
141  U = U->getNext();
142  return *this;
143  }
144 
145  use_iterator_impl operator++(int) { // Postincrement
146  auto tmp = *this;
147  ++*this;
148  return tmp;
149  }
150 
151  UseT &operator*() const {
152  assert(U && "Cannot dereference end iterator!");
153  return *U;
154  }
155 
156  UseT *operator->() const { return &operator*(); }
157 
158  operator use_iterator_impl<const UseT>() const {
159  return use_iterator_impl<const UseT>(U);
160  }
161  };
162 
163  template <typename UserTy> // UserTy == 'User' or 'const User'
164  class user_iterator_impl
165  : public std::iterator<std::forward_iterator_tag, UserTy *> {
166  use_iterator_impl<Use> UI;
167  explicit user_iterator_impl(Use *U) : UI(U) {}
168  friend class Value;
169 
170  public:
171  user_iterator_impl() = default;
172 
173  bool operator==(const user_iterator_impl &x) const { return UI == x.UI; }
174  bool operator!=(const user_iterator_impl &x) const { return !operator==(x); }
175 
176  /// \brief Returns true if this iterator is equal to user_end() on the value.
177  bool atEnd() const { return *this == user_iterator_impl(); }
178 
179  user_iterator_impl &operator++() { // Preincrement
180  ++UI;
181  return *this;
182  }
183 
184  user_iterator_impl operator++(int) { // Postincrement
185  auto tmp = *this;
186  ++*this;
187  return tmp;
188  }
189 
190  // Retrieve a pointer to the current User.
191  UserTy *operator*() const {
192  return UI->getUser();
193  }
194 
195  UserTy *operator->() const { return operator*(); }
196 
197  operator user_iterator_impl<const UserTy>() const {
198  return user_iterator_impl<const UserTy>(*UI);
199  }
200 
201  Use &getUse() const { return *UI; }
202  };
203 
204 protected:
205  Value(Type *Ty, unsigned scid);
206 
207  /// Value's destructor should be virtual by design, but that would require
208  /// that Value and all of its subclasses have a vtable that effectively
209  /// duplicates the information in the value ID. As a size optimization, the
210  /// destructor has been protected, and the caller should manually call
211  /// deleteValue.
212  ~Value(); // Use deleteValue() to delete a generic Value.
213 
214 public:
215  Value(const Value &) = delete;
216  Value &operator=(const Value &) = delete;
217 
218  /// Delete a pointer to a generic Value.
219  void deleteValue();
220 
221  /// \brief Support for debugging, callable in GDB: V->dump()
222  void dump() const;
223 
224  /// \brief Implement operator<< on Value.
225  /// @{
226  void print(raw_ostream &O, bool IsForDebug = false) const;
227  void print(raw_ostream &O, ModuleSlotTracker &MST,
228  bool IsForDebug = false) const;
229  /// @}
230 
231  /// \brief Print the name of this Value out to the specified raw_ostream.
232  ///
233  /// This is useful when you just want to print 'int %reg126', not the
234  /// instruction that generated it. If you specify a Module for context, then
235  /// even constanst get pretty-printed; for example, the type of a null
236  /// pointer is printed symbolically.
237  /// @{
238  void printAsOperand(raw_ostream &O, bool PrintType = true,
239  const Module *M = nullptr) const;
240  void printAsOperand(raw_ostream &O, bool PrintType,
241  ModuleSlotTracker &MST) const;
242  /// @}
243 
244  /// \brief All values are typed, get the type of this value.
245  Type *getType() const { return VTy; }
246 
247  /// \brief All values hold a context through their type.
248  LLVMContext &getContext() const;
249 
250  // \brief All values can potentially be named.
251  bool hasName() const { return HasName; }
252  ValueName *getValueName() const;
253  void setValueName(ValueName *VN);
254 
255 private:
256  void destroyValueName();
257  void doRAUW(Value *New, bool NoMetadata);
258  void setNameImpl(const Twine &Name);
259 
260 public:
261  /// \brief Return a constant reference to the value's name.
262  ///
263  /// This guaranteed to return the same reference as long as the value is not
264  /// modified. If the value has a name, this does a hashtable lookup, so it's
265  /// not free.
266  StringRef getName() const;
267 
268  /// \brief Change the name of the value.
269  ///
270  /// Choose a new unique name if the provided name is taken.
271  ///
272  /// \param Name The new name; or "" if the value's name should be removed.
273  void setName(const Twine &Name);
274 
275  /// \brief Transfer the name from V to this value.
276  ///
277  /// After taking V's name, sets V's name to empty.
278  ///
279  /// \note It is an error to call V->takeName(V).
280  void takeName(Value *V);
281 
282  /// \brief Change all uses of this to point to a new Value.
283  ///
284  /// Go through the uses list for this definition and make each use point to
285  /// "V" instead of "this". After this completes, 'this's use list is
286  /// guaranteed to be empty.
287  void replaceAllUsesWith(Value *V);
288 
289  /// \brief Change non-metadata uses of this to point to a new Value.
290  ///
291  /// Go through the uses list for this definition and make each use point to
292  /// "V" instead of "this". This function skips metadata entries in the list.
294 
295  /// replaceUsesOutsideBlock - Go through the uses list for this definition and
296  /// make each use point to "V" instead of "this" when the use is outside the
297  /// block. 'This's use list is expected to have at least one element.
298  /// Unlike replaceAllUsesWith this function does not support basic block
299  /// values or constant users.
301 
302  /// replaceUsesExceptBlockAddr - Go through the uses list for this definition
303  /// and make each use point to "V" instead of "this" when the use is outside
304  /// the block. 'This's use list is expected to have at least one element.
305  /// Unlike replaceAllUsesWith this function skips blockaddr uses.
307 
308  //----------------------------------------------------------------------
309  // Methods for handling the chain of uses of this Value.
310  //
311  // Materializing a function can introduce new uses, so these methods come in
312  // two variants:
313  // The methods that start with materialized_ check the uses that are
314  // currently known given which functions are materialized. Be very careful
315  // when using them since you might not get all uses.
316  // The methods that don't start with materialized_ assert that modules is
317  // fully materialized.
318  void assertModuleIsMaterializedImpl() const;
319  // This indirection exists so we can keep assertModuleIsMaterializedImpl()
320  // around in release builds of Value.cpp to be linked with other code built
321  // in debug mode. But this avoids calling it in any of the release built code.
323 #ifndef NDEBUG
325 #endif
326  }
327 
328  bool use_empty() const {
330  return UseList == nullptr;
331  }
332 
333  bool materialized_use_empty() const {
334  return UseList == nullptr;
335  }
336 
337  using use_iterator = use_iterator_impl<Use>;
338  using const_use_iterator = use_iterator_impl<const Use>;
339 
342  return const_use_iterator(UseList);
343  }
346  return materialized_use_begin();
347  }
350  return materialized_use_begin();
351  }
356  }
359  }
362  return materialized_uses();
363  }
366  return materialized_uses();
367  }
368 
369  bool user_empty() const {
371  return UseList == nullptr;
372  }
373 
374  using user_iterator = user_iterator_impl<User>;
375  using const_user_iterator = user_iterator_impl<const User>;
376 
379  return const_user_iterator(UseList);
380  }
383  return materialized_user_begin();
384  }
387  return materialized_user_begin();
388  }
393  return *materialized_user_begin();
394  }
395  const User *user_back() const {
397  return *materialized_user_begin();
398  }
401  }
404  }
407  return materialized_users();
408  }
411  return materialized_users();
412  }
413 
414  /// \brief Return true if there is exactly one user of this value.
415  ///
416  /// This is specialized because it is a common request and does not require
417  /// traversing the whole use list.
418  bool hasOneUse() const {
420  if (I == E) return false;
421  return ++I == E;
422  }
423 
424  /// \brief Return true if this Value has exactly N users.
425  bool hasNUses(unsigned N) const;
426 
427  /// \brief Return true if this value has N users or more.
428  ///
429  /// This is logically equivalent to getNumUses() >= N.
430  bool hasNUsesOrMore(unsigned N) const;
431 
432  /// \brief Check if this value is used in the specified basic block.
433  bool isUsedInBasicBlock(const BasicBlock *BB) const;
434 
435  /// \brief This method computes the number of uses of this Value.
436  ///
437  /// This is a linear time operation. Use hasOneUse, hasNUses, or
438  /// hasNUsesOrMore to check for specific values.
439  unsigned getNumUses() const;
440 
441  /// \brief This method should only be used by the Use class.
442  void addUse(Use &U) { U.addToList(&UseList); }
443 
444  /// \brief Concrete subclass of this.
445  ///
446  /// An enumeration for keeping track of the concrete subclass of Value that
447  /// is actually instantiated. Values of this enumeration are kept in the
448  /// Value classes SubclassID field. They are used for concrete type
449  /// identification.
450  enum ValueTy {
451 #define HANDLE_VALUE(Name) Name##Val,
452 #include "llvm/IR/Value.def"
453 
454  // Markers:
455 #define HANDLE_CONSTANT_MARKER(Marker, Constant) Marker = Constant##Val,
456 #include "llvm/IR/Value.def"
457  };
458 
459  /// \brief Return an ID for the concrete type of this object.
460  ///
461  /// This is used to implement the classof checks. This should not be used
462  /// for any other purpose, as the values may change as LLVM evolves. Also,
463  /// note that for instructions, the Instruction's opcode is added to
464  /// InstructionVal. So this means three things:
465  /// # there is no value with code InstructionVal (no opcode==0).
466  /// # there are more possible values for the value type than in ValueTy enum.
467  /// # the InstructionVal enumerator must be the highest valued enumerator in
468  /// the ValueTy enum.
469  unsigned getValueID() const {
470  return SubclassID;
471  }
472 
473  /// \brief Return the raw optional flags value contained in this value.
474  ///
475  /// This should only be used when testing two Values for equivalence.
476  unsigned getRawSubclassOptionalData() const {
477  return SubclassOptionalData;
478  }
479 
480  /// \brief Clear the optional flags contained in this value.
483  }
484 
485  /// \brief Check the optional flags for equality.
486  bool hasSameSubclassOptionalData(const Value *V) const {
488  }
489 
490  /// \brief Return true if there is a value handle associated with this value.
491  bool hasValueHandle() const { return HasValueHandle; }
492 
493  /// \brief Return true if there is metadata referencing this value.
494  bool isUsedByMetadata() const { return IsUsedByMD; }
495 
496  /// \brief Return true if this value is a swifterror value.
497  ///
498  /// swifterror values can be either a function argument or an alloca with a
499  /// swifterror attribute.
500  bool isSwiftError() const;
501 
502  /// \brief Strip off pointer casts, all-zero GEPs, and aliases.
503  ///
504  /// Returns the original uncasted value. If this is called on a non-pointer
505  /// value, it returns 'this'.
506  const Value *stripPointerCasts() const;
508  return const_cast<Value *>(
509  static_cast<const Value *>(this)->stripPointerCasts());
510  }
511 
512  /// \brief Strip off pointer casts, all-zero GEPs, aliases and barriers.
513  ///
514  /// Returns the original uncasted value. If this is called on a non-pointer
515  /// value, it returns 'this'. This function should be used only in
516  /// Alias analysis.
517  const Value *stripPointerCastsAndBarriers() const;
519  return const_cast<Value *>(
520  static_cast<const Value *>(this)->stripPointerCastsAndBarriers());
521  }
522 
523  /// \brief Strip off pointer casts and all-zero GEPs.
524  ///
525  /// Returns the original uncasted value. If this is called on a non-pointer
526  /// value, it returns 'this'.
529  return const_cast<Value *>(
530  static_cast<const Value *>(this)->stripPointerCastsNoFollowAliases());
531  }
532 
533  /// \brief Strip off pointer casts and all-constant inbounds GEPs.
534  ///
535  /// Returns the original pointer value. If this is called on a non-pointer
536  /// value, it returns 'this'.
537  const Value *stripInBoundsConstantOffsets() const;
539  return const_cast<Value *>(
540  static_cast<const Value *>(this)->stripInBoundsConstantOffsets());
541  }
542 
543  /// \brief Accumulate offsets from \a stripInBoundsConstantOffsets().
544  ///
545  /// Stores the resulting constant offset stripped into the APInt provided.
546  /// The provided APInt will be extended or truncated as needed to be the
547  /// correct bitwidth for an offset of this pointer type.
548  ///
549  /// If this is called on a non-pointer value, it returns 'this'.
551  APInt &Offset) const;
553  APInt &Offset) {
554  return const_cast<Value *>(static_cast<const Value *>(this)
556  }
557 
558  /// \brief Strip off pointer casts and inbounds GEPs.
559  ///
560  /// Returns the original pointer value. If this is called on a non-pointer
561  /// value, it returns 'this'.
562  const Value *stripInBoundsOffsets() const;
564  return const_cast<Value *>(
565  static_cast<const Value *>(this)->stripInBoundsOffsets());
566  }
567 
568  /// \brief Returns the number of bytes known to be dereferenceable for the
569  /// pointer value.
570  ///
571  /// If CanBeNull is set by this function the pointer can either be null or be
572  /// dereferenceable up to the returned number of bytes.
573  unsigned getPointerDereferenceableBytes(const DataLayout &DL,
574  bool &CanBeNull) const;
575 
576  /// \brief Returns an alignment of the pointer value.
577  ///
578  /// Returns an alignment which is either specified explicitly, e.g. via
579  /// align attribute of a function argument, or guaranteed by DataLayout.
580  unsigned getPointerAlignment(const DataLayout &DL) const;
581 
582  /// \brief Translate PHI node to its predecessor from the given basic block.
583  ///
584  /// If this value is a PHI node with CurBB as its parent, return the value in
585  /// the PHI node corresponding to PredBB. If not, return ourself. This is
586  /// useful if you want to know the value something has in a predecessor
587  /// block.
588  const Value *DoPHITranslation(const BasicBlock *CurBB,
589  const BasicBlock *PredBB) const;
590  Value *DoPHITranslation(const BasicBlock *CurBB, const BasicBlock *PredBB) {
591  return const_cast<Value *>(
592  static_cast<const Value *>(this)->DoPHITranslation(CurBB, PredBB));
593  }
594 
595  /// \brief The maximum alignment for instructions.
596  ///
597  /// This is the greatest alignment value supported by load, store, and alloca
598  /// instructions, and global values.
599  static const unsigned MaxAlignmentExponent = 29;
600  static const unsigned MaximumAlignment = 1u << MaxAlignmentExponent;
601 
602  /// \brief Mutate the type of this Value to be of the specified type.
603  ///
604  /// Note that this is an extremely dangerous operation which can create
605  /// completely invalid IR very easily. It is strongly recommended that you
606  /// recreate IR objects with the right types instead of mutating them in
607  /// place.
608  void mutateType(Type *Ty) {
609  VTy = Ty;
610  }
611 
612  /// \brief Sort the use-list.
613  ///
614  /// Sorts the Value's use-list by Cmp using a stable mergesort. Cmp is
615  /// expected to compare two \a Use references.
616  template <class Compare> void sortUseList(Compare Cmp);
617 
618  /// \brief Reverse the use-list.
619  void reverseUseList();
620 
621 private:
622  /// \brief Merge two lists together.
623  ///
624  /// Merges \c L and \c R using \c Cmp. To enable stable sorts, always pushes
625  /// "equal" items from L before items from R.
626  ///
627  /// \return the first element in the list.
628  ///
629  /// \note Completely ignores \a Use::Prev (doesn't read, doesn't update).
630  template <class Compare>
631  static Use *mergeUseLists(Use *L, Use *R, Compare Cmp) {
632  Use *Merged;
633  Use **Next = &Merged;
634 
635  while (true) {
636  if (!L) {
637  *Next = R;
638  break;
639  }
640  if (!R) {
641  *Next = L;
642  break;
643  }
644  if (Cmp(*R, *L)) {
645  *Next = R;
646  Next = &R->Next;
647  R = R->Next;
648  } else {
649  *Next = L;
650  Next = &L->Next;
651  L = L->Next;
652  }
653  }
654 
655  return Merged;
656  }
657 
658 protected:
659  unsigned short getSubclassDataFromValue() const { return SubclassData; }
660  void setValueSubclassData(unsigned short D) { SubclassData = D; }
661 };
662 
663 struct ValueDeleter { void operator()(Value *V) { V->deleteValue(); } };
664 
665 /// Use this instead of std::unique_ptr<Value> or std::unique_ptr<Instruction>.
666 /// Those don't work because Value and Instruction's destructors are protected,
667 /// aren't virtual, and won't destroy the complete object.
668 using unique_value = std::unique_ptr<Value, ValueDeleter>;
669 
670 inline raw_ostream &operator<<(raw_ostream &OS, const Value &V) {
671  V.print(OS);
672  return OS;
673 }
674 
675 void Use::set(Value *V) {
676  if (Val) removeFromList();
677  Val = V;
678  if (V) V->addUse(*this);
679 }
680 
682  set(RHS);
683  return RHS;
684 }
685 
686 const Use &Use::operator=(const Use &RHS) {
687  set(RHS.Val);
688  return *this;
689 }
690 
691 template <class Compare> void Value::sortUseList(Compare Cmp) {
692  if (!UseList || !UseList->Next)
693  // No need to sort 0 or 1 uses.
694  return;
695 
696  // Note: this function completely ignores Prev pointers until the end when
697  // they're fixed en masse.
698 
699  // Create a binomial vector of sorted lists, visiting uses one at a time and
700  // merging lists as necessary.
701  const unsigned MaxSlots = 32;
702  Use *Slots[MaxSlots];
703 
704  // Collect the first use, turning it into a single-item list.
705  Use *Next = UseList->Next;
706  UseList->Next = nullptr;
707  unsigned NumSlots = 1;
708  Slots[0] = UseList;
709 
710  // Collect all but the last use.
711  while (Next->Next) {
712  Use *Current = Next;
713  Next = Current->Next;
714 
715  // Turn Current into a single-item list.
716  Current->Next = nullptr;
717 
718  // Save Current in the first available slot, merging on collisions.
719  unsigned I;
720  for (I = 0; I < NumSlots; ++I) {
721  if (!Slots[I])
722  break;
723 
724  // Merge two lists, doubling the size of Current and emptying slot I.
725  //
726  // Since the uses in Slots[I] originally preceded those in Current, send
727  // Slots[I] in as the left parameter to maintain a stable sort.
728  Current = mergeUseLists(Slots[I], Current, Cmp);
729  Slots[I] = nullptr;
730  }
731  // Check if this is a new slot.
732  if (I == NumSlots) {
733  ++NumSlots;
734  assert(NumSlots <= MaxSlots && "Use list bigger than 2^32");
735  }
736 
737  // Found an open slot.
738  Slots[I] = Current;
739  }
740 
741  // Merge all the lists together.
742  assert(Next && "Expected one more Use");
743  assert(!Next->Next && "Expected only one Use");
744  UseList = Next;
745  for (unsigned I = 0; I < NumSlots; ++I)
746  if (Slots[I])
747  // Since the uses in Slots[I] originally preceded those in UseList, send
748  // Slots[I] in as the left parameter to maintain a stable sort.
749  UseList = mergeUseLists(Slots[I], UseList, Cmp);
750 
751  // Fix the Prev pointers.
752  for (Use *I = UseList, **Prev = &UseList; I; I = I->Next) {
753  I->setPrev(Prev);
754  Prev = &I->Next;
755  }
756 }
757 
758 // isa - Provide some specializations of isa so that we don't have to include
759 // the subtype header files to test to see if the value is a subclass...
760 //
761 template <> struct isa_impl<Constant, Value> {
762  static inline bool doit(const Value &Val) {
763  static_assert(Value::ConstantFirstVal == 0, "Val.getValueID() >= Value::ConstantFirstVal");
764  return Val.getValueID() <= Value::ConstantLastVal;
765  }
766 };
767 
768 template <> struct isa_impl<ConstantData, Value> {
769  static inline bool doit(const Value &Val) {
770  return Val.getValueID() >= Value::ConstantDataFirstVal &&
771  Val.getValueID() <= Value::ConstantDataLastVal;
772  }
773 };
774 
775 template <> struct isa_impl<ConstantAggregate, Value> {
776  static inline bool doit(const Value &Val) {
777  return Val.getValueID() >= Value::ConstantAggregateFirstVal &&
778  Val.getValueID() <= Value::ConstantAggregateLastVal;
779  }
780 };
781 
782 template <> struct isa_impl<Argument, Value> {
783  static inline bool doit (const Value &Val) {
784  return Val.getValueID() == Value::ArgumentVal;
785  }
786 };
787 
788 template <> struct isa_impl<InlineAsm, Value> {
789  static inline bool doit(const Value &Val) {
790  return Val.getValueID() == Value::InlineAsmVal;
791  }
792 };
793 
794 template <> struct isa_impl<Instruction, Value> {
795  static inline bool doit(const Value &Val) {
796  return Val.getValueID() >= Value::InstructionVal;
797  }
798 };
799 
800 template <> struct isa_impl<BasicBlock, Value> {
801  static inline bool doit(const Value &Val) {
802  return Val.getValueID() == Value::BasicBlockVal;
803  }
804 };
805 
806 template <> struct isa_impl<Function, Value> {
807  static inline bool doit(const Value &Val) {
808  return Val.getValueID() == Value::FunctionVal;
809  }
810 };
811 
812 template <> struct isa_impl<GlobalVariable, Value> {
813  static inline bool doit(const Value &Val) {
814  return Val.getValueID() == Value::GlobalVariableVal;
815  }
816 };
817 
818 template <> struct isa_impl<GlobalAlias, Value> {
819  static inline bool doit(const Value &Val) {
820  return Val.getValueID() == Value::GlobalAliasVal;
821  }
822 };
823 
824 template <> struct isa_impl<GlobalIFunc, Value> {
825  static inline bool doit(const Value &Val) {
826  return Val.getValueID() == Value::GlobalIFuncVal;
827  }
828 };
829 
830 template <> struct isa_impl<GlobalIndirectSymbol, Value> {
831  static inline bool doit(const Value &Val) {
832  return isa<GlobalAlias>(Val) || isa<GlobalIFunc>(Val);
833  }
834 };
835 
836 template <> struct isa_impl<GlobalValue, Value> {
837  static inline bool doit(const Value &Val) {
838  return isa<GlobalObject>(Val) || isa<GlobalIndirectSymbol>(Val);
839  }
840 };
841 
842 template <> struct isa_impl<GlobalObject, Value> {
843  static inline bool doit(const Value &Val) {
844  return isa<GlobalVariable>(Val) || isa<Function>(Val);
845  }
846 };
847 
848 // Create wrappers for C Binding types (see CBindingWrapping.h).
850 
851 // Specialized opaque value conversions.
853  return reinterpret_cast<Value**>(Vals);
854 }
855 
856 template<typename T>
857 inline T **unwrap(LLVMValueRef *Vals, unsigned Length) {
858 #ifndef NDEBUG
859  for (LLVMValueRef *I = Vals, *E = Vals + Length; I != E; ++I)
860  unwrap<T>(*I); // For side effect of calling assert on invalid usage.
861 #endif
862  (void)Length;
863  return reinterpret_cast<T**>(Vals);
864 }
865 
866 inline LLVMValueRef *wrap(const Value **Vals) {
867  return reinterpret_cast<LLVMValueRef*>(const_cast<Value**>(Vals));
868 }
869 
870 } // end namespace llvm
871 
872 #endif // LLVM_IR_VALUE_H
This is the common base class of value handles.
Definition: ValueHandle.h:30
unsigned short getSubclassDataFromValue() const
Definition: Value.h:659
void sortUseList(Compare Cmp)
Sort the use-list.
Definition: Value.h:691
use_iterator use_end()
Definition: Value.h:352
A parsed version of the target data layout string in and methods for querying it. ...
Definition: DataLayout.h:109
unsigned HasDescriptor
Definition: Value.h:121
iterator_range< use_iterator > uses()
Definition: Value.h:360
void operator()(Value *V)
Definition: Value.h:663
This class represents an incoming formal argument to a Function.
Definition: Argument.h:30
unsigned getValueID() const
Return an ID for the concrete type of this object.
Definition: Value.h:469
const Value * stripInBoundsOffsets() const
Strip off pointer casts and inbounds GEPs.
Definition: Value.cpp:618
static bool doit(const Value &Val)
Definition: Value.h:776
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
void addUse(Use &U)
This method should only be used by the Use class.
Definition: Value.h:442
StringMapEntry - This is used to represent one value that is inserted into a StringMap.
Definition: StringMap.h:126
Various leaf nodes.
Definition: ISDOpcodes.h:60
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:63
bool user_empty() const
Definition: Value.h:369
const Value * stripPointerCastsAndBarriers() const
Strip off pointer casts, all-zero GEPs, aliases and barriers.
Definition: Value.cpp:570
This provides a very simple, boring adaptor for a begin and end iterator into a range type...
use_iterator materialized_use_begin()
Definition: Value.h:340
bool hasValueHandle() const
Return true if there is a value handle associated with this value.
Definition: Value.h:491
iterator_range< const_user_iterator > users() const
Definition: Value.h:409
LLVMContext & getContext() const
All values hold a context through their type.
Definition: Value.cpp:728
static bool doit(const Value &Val)
Definition: Value.h:813
void deleteValue()
Delete a pointer to a generic Value.
Definition: Value.cpp:95
Manage lifetime of a slot tracker for printing IR.
This defines the Use class.
use_iterator_impl< const Use > const_use_iterator
Definition: Value.h:338
const Value * DoPHITranslation(const BasicBlock *CurBB, const BasicBlock *PredBB) const
Translate PHI node to its predecessor from the given basic block.
Definition: Value.cpp:720
unsigned getPointerAlignment(const DataLayout &DL) const
Returns an alignment of the pointer value.
Definition: Value.cpp:673
iterator_range< user_iterator > materialized_users()
Definition: Value.h:399
void dump() const
Support for debugging, callable in GDB: V->dump()
Definition: AsmWriter.cpp:3641
const_user_iterator materialized_user_begin() const
Definition: Value.h:378
iterator_range< const_user_iterator > materialized_users() const
Definition: Value.h:402
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
Attribute unwrap(LLVMAttributeRef Attr)
Definition: Attributes.h:195
A Use represents the edge between a Value definition and its users.
Definition: Use.h:56
void setName(const Twine &Name)
Change the name of the value.
Definition: Value.cpp:286
void assertModuleIsMaterializedImpl() const
Definition: Value.cpp:352
static bool doit(const Value &Val)
Definition: Value.h:801
static const unsigned MaximumAlignment
Definition: Value.h:600
#define DEFINE_ISA_CONVERSION_FUNCTIONS(ty, ref)
APInt operator*(APInt a, uint64_t RHS)
Definition: APInt.h:2070
static bool doit(const Value &Val)
Definition: Value.h:789
unsigned getPointerDereferenceableBytes(const DataLayout &DL, bool &CanBeNull) const
Returns the number of bytes known to be dereferenceable for the pointer value.
Definition: Value.cpp:622
Value * stripInBoundsOffsets()
Definition: Value.h:563
unsigned HasHungOffUses
Definition: Value.h:120
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:245
iterator_range< const_use_iterator > materialized_uses() const
Definition: Value.h:357
bool isSwiftError() const
Return true if this value is a swifterror value.
Definition: Value.cpp:749
static bool doit(const Value &Val)
Definition: Value.h:831
const_use_iterator use_end() const
Definition: Value.h:353
const_use_iterator materialized_use_begin() const
Definition: Value.h:341
Value * stripPointerCastsNoFollowAliases()
Definition: Value.h:528
void replaceAllUsesWith(Value *V)
Change all uses of this to point to a new Value.
Definition: Value.cpp:430
Value wrapper in the Metadata hierarchy.
Definition: Metadata.h:337
void takeName(Value *V)
Transfer the name from V to this value.
Definition: Value.cpp:292
use_iterator_impl< Use > use_iterator
Definition: Value.h:337
unsigned getRawSubclassOptionalData() const
Return the raw optional flags value contained in this value.
Definition: Value.h:476
const_use_iterator use_begin() const
Definition: Value.h:348
bool hasNUsesOrMore(unsigned N) const
Return true if this value has N users or more.
Definition: Value.cpp:136
bool hasNUses(unsigned N) const
Return true if this Value has exactly N users.
Definition: Value.cpp:128
void set(Value *Val)
Definition: Value.h:675
bool hasName() const
Definition: Value.h:251
LLVM Basic Block Representation.
Definition: BasicBlock.h:59
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:46
This is an important class for using LLVM in a threaded context.
Definition: LLVMContext.h:69
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
This is an important base class in LLVM.
Definition: Constant.h:42
void replaceNonMetadataUsesWith(Value *V)
Change non-metadata uses of this to point to a new Value.
Definition: Value.cpp:434
amdgpu inline
iterator_range< use_iterator > materialized_uses()
Definition: Value.h:354
bool isUsedInBasicBlock(const BasicBlock *BB) const
Check if this value is used in the specified basic block.
Definition: Value.cpp:145
bool hasSameSubclassOptionalData(const Value *V) const
Check the optional flags for equality.
Definition: Value.h:486
static bool doit(const Value &Val)
Definition: Value.h:825
void print(raw_ostream &O, bool IsForDebug=false) const
Implement operator<< on Value.
Definition: AsmWriter.cpp:3494
Value * stripInBoundsConstantOffsets()
Definition: Value.h:538
const Value * stripPointerCasts() const
Strip off pointer casts, all-zero GEPs, and aliases.
Definition: Value.cpp:558
Value(Type *Ty, unsigned scid)
Definition: Value.cpp:50
void printAsOperand(raw_ostream &O, bool PrintType=true, const Module *M=nullptr) const
Print the name of this Value out to the specified raw_ostream.
Definition: AsmWriter.cpp:3573
Value * stripPointerCasts()
Definition: Value.h:507
Value & operator=(const Value &)=delete
unsigned char SubclassOptionalData
Hold subclass data that can be dropped.
Definition: Value.h:91
iterator_range< T > make_range(T x, T y)
Convenience function for iterating over sub-ranges.
static const unsigned MaxAlignmentExponent
The maximum alignment for instructions.
Definition: Value.h:599
bool materialized_use_empty() const
Definition: Value.h:333
unsigned IsUsedByMD
Definition: Value.h:118
void assertModuleIsMaterialized() const
Definition: Value.h:322
static bool doit(const Value &Val)
Definition: Value.h:843
ValueName * getValueName() const
Definition: Value.cpp:192
const User * user_back() const
Definition: Value.h:395
std::unique_ptr< Value, ValueDeleter > unique_value
Use this instead of std::unique_ptr<Value> or std::unique_ptr<Instruction>.
Definition: Value.h:668
static GCRegistry::Add< StatepointGC > D("statepoint-example", "an example strategy for statepoint")
unsigned NumUserOperands
Definition: Value.h:115
ValueTy
Concrete subclass of this.
Definition: Value.h:450
void setValueSubclassData(unsigned short D)
Definition: Value.h:660
bool isUsedByMetadata() const
Return true if there is metadata referencing this value.
Definition: Value.h:494
A range adaptor for a pair of iterators.
const Value * stripAndAccumulateInBoundsConstantOffsets(const DataLayout &DL, APInt &Offset) const
Accumulate offsets from stripInBoundsConstantOffsets().
Definition: Value.cpp:576
Class for arbitrary precision integers.
Definition: APInt.h:69
const_user_iterator user_begin() const
Definition: Value.h:385
iterator_range< user_iterator > users()
Definition: Value.h:405
user_iterator_impl< const User > const_user_iterator
Definition: Value.h:375
could "use" a pointer
void reverseUseList()
Reverse the use-list.
Definition: Value.cpp:730
iterator_range< const_use_iterator > uses() const
Definition: Value.h:364
use_iterator use_begin()
Definition: Value.h:344
bool operator!=(uint64_t V1, const APInt &V2)
Definition: APInt.h:1948
unsigned getNumUses() const
This method computes the number of uses of this Value.
Definition: Value.cpp:166
unsigned HasName
Definition: Value.h:119
LLVMAttributeRef wrap(Attribute Attr)
Definition: Attributes.h:190
static bool doit(const Value &Val)
Definition: Value.h:795
const Value * stripPointerCastsNoFollowAliases() const
Strip off pointer casts and all-zero GEPs.
Definition: Value.cpp:562
StringRef getName() const
Return a constant reference to the value&#39;s name.
Definition: Value.cpp:220
#define I(x, y, z)
Definition: MD5.cpp:58
#define N
user_iterator_impl< User > user_iterator
Definition: Value.h:374
Value * DoPHITranslation(const BasicBlock *CurBB, const BasicBlock *PredBB)
Definition: Value.h:590
static bool doit(const Value &Val)
Definition: Value.h:762
raw_ostream & operator<<(raw_ostream &OS, const APInt &I)
Definition: APInt.h:2018
void mutateType(Type *Ty)
Mutate the type of this Value to be of the specified type.
Definition: Value.h:608
~Value()
Value&#39;s destructor should be virtual by design, but that would require that Value and all of its subc...
Definition: Value.cpp:69
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
user_iterator user_begin()
Definition: Value.h:381
Value * stripAndAccumulateInBoundsConstantOffsets(const DataLayout &DL, APInt &Offset)
Definition: Value.h:552
Base class for aggregate constants (with operands).
Definition: Constants.h:381
LLVM Value Representation.
Definition: Value.h:73
const_user_iterator user_end() const
Definition: Value.h:390
void clearSubclassOptionalData()
Clear the optional flags contained in this value.
Definition: Value.h:481
static bool doit(const Value &Val)
Definition: Value.h:783
Value * stripPointerCastsAndBarriers()
Definition: Value.h:518
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:44
user_iterator materialized_user_begin()
Definition: Value.h:377
void setValueName(ValueName *VN)
Definition: Value.cpp:203
static bool doit(const Value &Val)
Definition: Value.h:837
bool hasOneUse() const
Return true if there is exactly one user of this value.
Definition: Value.h:418
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
static bool doit(const Value &Val)
Definition: Value.h:819
void replaceUsesOutsideBlock(Value *V, BasicBlock *BB)
replaceUsesOutsideBlock - Go through the uses list for this definition and make each use point to "V"...
Definition: Value.cpp:440
bool operator==(uint64_t V1, const APInt &V2)
Definition: APInt.h:1946
const Value * stripInBoundsConstantOffsets() const
Strip off pointer casts and all-constant inbounds GEPs.
Definition: Value.cpp:566
void replaceUsesExceptBlockAddr(Value *New)
replaceUsesExceptBlockAddr - Go through the uses list for this definition and make each use point to ...
Definition: Value.cpp:459
Base class for constants with no operands.
Definition: Constants.h:58
Value * operator=(Value *RHS)
Definition: Value.h:681
bool use_empty() const
Definition: Value.h:328
static bool doit(const Value &Val)
Definition: Value.h:807
struct LLVMOpaqueValue * LLVMValueRef
Represents an individual value in LLVM IR.
Definition: Types.h:76
User * user_back()
Definition: Value.h:391
static bool doit(const Value &Val)
Definition: Value.h:769
user_iterator user_end()
Definition: Value.h:389