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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 /// 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  /// 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  /// 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  /// 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  /// 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  /// Support for debugging, callable in GDB: V->dump()
222  void dump() const;
223 
224  /// 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  /// 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  /// All values are typed, get the type of this value.
245  Type *getType() const { return VTy; }
246 
247  /// All values hold a context through their type.
248  LLVMContext &getContext() const;
249 
250  // 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  /// 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  /// 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  /// 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  /// 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  /// 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  /// 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  /// Return true if this Value has exactly N users.
425  bool hasNUses(unsigned N) const;
426 
427  /// 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  /// Check if this value is used in the specified basic block.
433  bool isUsedInBasicBlock(const BasicBlock *BB) const;
434 
435  /// 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  /// This method should only be used by the Use class.
442  void addUse(Use &U) { U.addToList(&UseList); }
443 
444  /// 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  /// 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  /// 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  /// Clear the optional flags contained in this value.
483  }
484 
485  /// Check the optional flags for equality.
486  bool hasSameSubclassOptionalData(const Value *V) const {
488  }
489 
490  /// Return true if there is a value handle associated with this value.
491  bool hasValueHandle() const { return HasValueHandle; }
492 
493  /// Return true if there is metadata referencing this value.
494  bool isUsedByMetadata() const { return IsUsedByMD; }
495 
496  /// 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  /// 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  /// Strip off pointer casts, all-zero GEPs, aliases and invariant group
513  /// info.
514  ///
515  /// Returns the original uncasted value. If this is called on a non-pointer
516  /// value, it returns 'this'. This function should be used only in
517  /// Alias analysis.
520  return const_cast<Value *>(
521  static_cast<const Value *>(this)->stripPointerCastsAndInvariantGroups());
522  }
523 
524  /// Strip off pointer casts and all-zero GEPs.
525  ///
526  /// Returns the original uncasted value. If this is called on a non-pointer
527  /// value, it returns 'this'.
530  return const_cast<Value *>(
531  static_cast<const Value *>(this)->stripPointerCastsNoFollowAliases());
532  }
533 
534  /// Strip off pointer casts and all-constant inbounds GEPs.
535  ///
536  /// Returns the original pointer value. If this is called on a non-pointer
537  /// value, it returns 'this'.
538  const Value *stripInBoundsConstantOffsets() const;
540  return const_cast<Value *>(
541  static_cast<const Value *>(this)->stripInBoundsConstantOffsets());
542  }
543 
544  /// Accumulate offsets from \a stripInBoundsConstantOffsets().
545  ///
546  /// Stores the resulting constant offset stripped into the APInt provided.
547  /// The provided APInt will be extended or truncated as needed to be the
548  /// correct bitwidth for an offset of this pointer type.
549  ///
550  /// If this is called on a non-pointer value, it returns 'this'.
552  APInt &Offset) const;
554  APInt &Offset) {
555  return const_cast<Value *>(static_cast<const Value *>(this)
557  }
558 
559  /// Strip off pointer casts and inbounds GEPs.
560  ///
561  /// Returns the original pointer value. If this is called on a non-pointer
562  /// value, it returns 'this'.
563  const Value *stripInBoundsOffsets() const;
565  return const_cast<Value *>(
566  static_cast<const Value *>(this)->stripInBoundsOffsets());
567  }
568 
569  /// Returns the number of bytes known to be dereferenceable for the
570  /// pointer value.
571  ///
572  /// If CanBeNull is set by this function the pointer can either be null or be
573  /// dereferenceable up to the returned number of bytes.
574  uint64_t getPointerDereferenceableBytes(const DataLayout &DL,
575  bool &CanBeNull) const;
576 
577  /// Returns an alignment of the pointer value.
578  ///
579  /// Returns an alignment which is either specified explicitly, e.g. via
580  /// align attribute of a function argument, or guaranteed by DataLayout.
581  unsigned getPointerAlignment(const DataLayout &DL) const;
582 
583  /// Translate PHI node to its predecessor from the given basic block.
584  ///
585  /// If this value is a PHI node with CurBB as its parent, return the value in
586  /// the PHI node corresponding to PredBB. If not, return ourself. This is
587  /// useful if you want to know the value something has in a predecessor
588  /// block.
589  const Value *DoPHITranslation(const BasicBlock *CurBB,
590  const BasicBlock *PredBB) const;
591  Value *DoPHITranslation(const BasicBlock *CurBB, const BasicBlock *PredBB) {
592  return const_cast<Value *>(
593  static_cast<const Value *>(this)->DoPHITranslation(CurBB, PredBB));
594  }
595 
596  /// The maximum alignment for instructions.
597  ///
598  /// This is the greatest alignment value supported by load, store, and alloca
599  /// instructions, and global values.
600  static const unsigned MaxAlignmentExponent = 29;
601  static const unsigned MaximumAlignment = 1u << MaxAlignmentExponent;
602 
603  /// Mutate the type of this Value to be of the specified type.
604  ///
605  /// Note that this is an extremely dangerous operation which can create
606  /// completely invalid IR very easily. It is strongly recommended that you
607  /// recreate IR objects with the right types instead of mutating them in
608  /// place.
609  void mutateType(Type *Ty) {
610  VTy = Ty;
611  }
612 
613  /// Sort the use-list.
614  ///
615  /// Sorts the Value's use-list by Cmp using a stable mergesort. Cmp is
616  /// expected to compare two \a Use references.
617  template <class Compare> void sortUseList(Compare Cmp);
618 
619  /// Reverse the use-list.
620  void reverseUseList();
621 
622 private:
623  /// Merge two lists together.
624  ///
625  /// Merges \c L and \c R using \c Cmp. To enable stable sorts, always pushes
626  /// "equal" items from L before items from R.
627  ///
628  /// \return the first element in the list.
629  ///
630  /// \note Completely ignores \a Use::Prev (doesn't read, doesn't update).
631  template <class Compare>
632  static Use *mergeUseLists(Use *L, Use *R, Compare Cmp) {
633  Use *Merged;
634  Use **Next = &Merged;
635 
636  while (true) {
637  if (!L) {
638  *Next = R;
639  break;
640  }
641  if (!R) {
642  *Next = L;
643  break;
644  }
645  if (Cmp(*R, *L)) {
646  *Next = R;
647  Next = &R->Next;
648  R = R->Next;
649  } else {
650  *Next = L;
651  Next = &L->Next;
652  L = L->Next;
653  }
654  }
655 
656  return Merged;
657  }
658 
659 protected:
660  unsigned short getSubclassDataFromValue() const { return SubclassData; }
661  void setValueSubclassData(unsigned short D) { SubclassData = D; }
662 };
663 
664 struct ValueDeleter { void operator()(Value *V) { V->deleteValue(); } };
665 
666 /// Use this instead of std::unique_ptr<Value> or std::unique_ptr<Instruction>.
667 /// Those don't work because Value and Instruction's destructors are protected,
668 /// aren't virtual, and won't destroy the complete object.
669 using unique_value = std::unique_ptr<Value, ValueDeleter>;
670 
671 inline raw_ostream &operator<<(raw_ostream &OS, const Value &V) {
672  V.print(OS);
673  return OS;
674 }
675 
676 void Use::set(Value *V) {
677  if (Val) removeFromList();
678  Val = V;
679  if (V) V->addUse(*this);
680 }
681 
683  set(RHS);
684  return RHS;
685 }
686 
687 const Use &Use::operator=(const Use &RHS) {
688  set(RHS.Val);
689  return *this;
690 }
691 
692 template <class Compare> void Value::sortUseList(Compare Cmp) {
693  if (!UseList || !UseList->Next)
694  // No need to sort 0 or 1 uses.
695  return;
696 
697  // Note: this function completely ignores Prev pointers until the end when
698  // they're fixed en masse.
699 
700  // Create a binomial vector of sorted lists, visiting uses one at a time and
701  // merging lists as necessary.
702  const unsigned MaxSlots = 32;
703  Use *Slots[MaxSlots];
704 
705  // Collect the first use, turning it into a single-item list.
706  Use *Next = UseList->Next;
707  UseList->Next = nullptr;
708  unsigned NumSlots = 1;
709  Slots[0] = UseList;
710 
711  // Collect all but the last use.
712  while (Next->Next) {
713  Use *Current = Next;
714  Next = Current->Next;
715 
716  // Turn Current into a single-item list.
717  Current->Next = nullptr;
718 
719  // Save Current in the first available slot, merging on collisions.
720  unsigned I;
721  for (I = 0; I < NumSlots; ++I) {
722  if (!Slots[I])
723  break;
724 
725  // Merge two lists, doubling the size of Current and emptying slot I.
726  //
727  // Since the uses in Slots[I] originally preceded those in Current, send
728  // Slots[I] in as the left parameter to maintain a stable sort.
729  Current = mergeUseLists(Slots[I], Current, Cmp);
730  Slots[I] = nullptr;
731  }
732  // Check if this is a new slot.
733  if (I == NumSlots) {
734  ++NumSlots;
735  assert(NumSlots <= MaxSlots && "Use list bigger than 2^32");
736  }
737 
738  // Found an open slot.
739  Slots[I] = Current;
740  }
741 
742  // Merge all the lists together.
743  assert(Next && "Expected one more Use");
744  assert(!Next->Next && "Expected only one Use");
745  UseList = Next;
746  for (unsigned I = 0; I < NumSlots; ++I)
747  if (Slots[I])
748  // Since the uses in Slots[I] originally preceded those in UseList, send
749  // Slots[I] in as the left parameter to maintain a stable sort.
750  UseList = mergeUseLists(Slots[I], UseList, Cmp);
751 
752  // Fix the Prev pointers.
753  for (Use *I = UseList, **Prev = &UseList; I; I = I->Next) {
754  I->setPrev(Prev);
755  Prev = &I->Next;
756  }
757 }
758 
759 // isa - Provide some specializations of isa so that we don't have to include
760 // the subtype header files to test to see if the value is a subclass...
761 //
762 template <> struct isa_impl<Constant, Value> {
763  static inline bool doit(const Value &Val) {
764  static_assert(Value::ConstantFirstVal == 0, "Val.getValueID() >= Value::ConstantFirstVal");
765  return Val.getValueID() <= Value::ConstantLastVal;
766  }
767 };
768 
769 template <> struct isa_impl<ConstantData, Value> {
770  static inline bool doit(const Value &Val) {
771  return Val.getValueID() >= Value::ConstantDataFirstVal &&
772  Val.getValueID() <= Value::ConstantDataLastVal;
773  }
774 };
775 
776 template <> struct isa_impl<ConstantAggregate, Value> {
777  static inline bool doit(const Value &Val) {
778  return Val.getValueID() >= Value::ConstantAggregateFirstVal &&
779  Val.getValueID() <= Value::ConstantAggregateLastVal;
780  }
781 };
782 
783 template <> struct isa_impl<Argument, Value> {
784  static inline bool doit (const Value &Val) {
785  return Val.getValueID() == Value::ArgumentVal;
786  }
787 };
788 
789 template <> struct isa_impl<InlineAsm, Value> {
790  static inline bool doit(const Value &Val) {
791  return Val.getValueID() == Value::InlineAsmVal;
792  }
793 };
794 
795 template <> struct isa_impl<Instruction, Value> {
796  static inline bool doit(const Value &Val) {
797  return Val.getValueID() >= Value::InstructionVal;
798  }
799 };
800 
801 template <> struct isa_impl<BasicBlock, Value> {
802  static inline bool doit(const Value &Val) {
803  return Val.getValueID() == Value::BasicBlockVal;
804  }
805 };
806 
807 template <> struct isa_impl<Function, Value> {
808  static inline bool doit(const Value &Val) {
809  return Val.getValueID() == Value::FunctionVal;
810  }
811 };
812 
813 template <> struct isa_impl<GlobalVariable, Value> {
814  static inline bool doit(const Value &Val) {
815  return Val.getValueID() == Value::GlobalVariableVal;
816  }
817 };
818 
819 template <> struct isa_impl<GlobalAlias, Value> {
820  static inline bool doit(const Value &Val) {
821  return Val.getValueID() == Value::GlobalAliasVal;
822  }
823 };
824 
825 template <> struct isa_impl<GlobalIFunc, Value> {
826  static inline bool doit(const Value &Val) {
827  return Val.getValueID() == Value::GlobalIFuncVal;
828  }
829 };
830 
831 template <> struct isa_impl<GlobalIndirectSymbol, Value> {
832  static inline bool doit(const Value &Val) {
833  return isa<GlobalAlias>(Val) || isa<GlobalIFunc>(Val);
834  }
835 };
836 
837 template <> struct isa_impl<GlobalValue, Value> {
838  static inline bool doit(const Value &Val) {
839  return isa<GlobalObject>(Val) || isa<GlobalIndirectSymbol>(Val);
840  }
841 };
842 
843 template <> struct isa_impl<GlobalObject, Value> {
844  static inline bool doit(const Value &Val) {
845  return isa<GlobalVariable>(Val) || isa<Function>(Val);
846  }
847 };
848 
849 // Create wrappers for C Binding types (see CBindingWrapping.h).
851 
852 // Specialized opaque value conversions.
854  return reinterpret_cast<Value**>(Vals);
855 }
856 
857 template<typename T>
858 inline T **unwrap(LLVMValueRef *Vals, unsigned Length) {
859 #ifndef NDEBUG
860  for (LLVMValueRef *I = Vals, *E = Vals + Length; I != E; ++I)
861  unwrap<T>(*I); // For side effect of calling assert on invalid usage.
862 #endif
863  (void)Length;
864  return reinterpret_cast<T**>(Vals);
865 }
866 
867 inline LLVMValueRef *wrap(const Value **Vals) {
868  return reinterpret_cast<LLVMValueRef*>(const_cast<Value**>(Vals));
869 }
870 
871 } // end namespace llvm
872 
873 #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:660
void sortUseList(Compare Cmp)
Sort the use-list.
Definition: Value.h:692
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:111
unsigned HasDescriptor
Definition: Value.h:121
iterator_range< use_iterator > uses()
Definition: Value.h:360
void operator()(Value *V)
Definition: Value.h:664
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:627
static bool doit(const Value &Val)
Definition: Value.h:777
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
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:742
static bool doit(const Value &Val)
Definition: Value.h:814
void deleteValue()
Delete a pointer to a generic Value.
Definition: Value.cpp:99
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:734
unsigned getPointerAlignment(const DataLayout &DL) const
Returns an alignment of the pointer value.
Definition: Value.cpp:683
iterator_range< user_iterator > materialized_users()
Definition: Value.h:399
void dump() const
Support for debugging, callable in GDB: V->dump()
Definition: AsmWriter.cpp:3697
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:295
void assertModuleIsMaterializedImpl() const
Definition: Value.cpp:361
static bool doit(const Value &Val)
Definition: Value.h:802
static const unsigned MaximumAlignment
Definition: Value.h:601
#define DEFINE_ISA_CONVERSION_FUNCTIONS(ty, ref)
APInt operator*(APInt a, uint64_t RHS)
Definition: APInt.h:2075
static bool doit(const Value &Val)
Definition: Value.h:790
Value * stripInBoundsOffsets()
Definition: Value.h:564
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:763
static bool doit(const Value &Val)
Definition: Value.h:832
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:529
void replaceAllUsesWith(Value *V)
Change all uses of this to point to a new Value.
Definition: Value.cpp:439
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:301
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:140
bool hasNUses(unsigned N) const
Return true if this Value has exactly N users.
Definition: Value.cpp:132
void set(Value *Val)
Definition: Value.h:676
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:443
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:149
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:826
Value * stripPointerCastsAndInvariantGroups()
Definition: Value.h:519
void print(raw_ostream &O, bool IsForDebug=false) const
Implement operator<< on Value.
Definition: AsmWriter.cpp:3554
Value * stripInBoundsConstantOffsets()
Definition: Value.h:539
const Value * stripPointerCasts() const
Strip off pointer casts, all-zero GEPs, and aliases.
Definition: Value.cpp:567
Value(Type *Ty, unsigned scid)
Definition: Value.cpp:54
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:3631
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:600
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:844
ValueName * getValueName() const
Definition: Value.cpp:196
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:669
uint64_t getPointerDereferenceableBytes(const DataLayout &DL, bool &CanBeNull) const
Returns the number of bytes known to be dereferenceable for the pointer value.
Definition: Value.cpp:631
static GCRegistry::Add< StatepointGC > D("statepoint-example", "an example strategy for statepoint")
unsigned NumUserOperands
Definition: Value.h:115
const Value * stripPointerCastsAndInvariantGroups() const
Strip off pointer casts, all-zero GEPs, aliases and invariant group info.
Definition: Value.cpp:579
ValueTy
Concrete subclass of this.
Definition: Value.h:450
void setValueSubclassData(unsigned short D)
Definition: Value.h:661
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:585
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:744
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:1953
unsigned getNumUses() const
This method computes the number of uses of this Value.
Definition: Value.cpp:170
unsigned HasName
Definition: Value.h:119
LLVMAttributeRef wrap(Attribute Attr)
Definition: Attributes.h:190
static bool doit(const Value &Val)
Definition: Value.h:796
const Value * stripPointerCastsNoFollowAliases() const
Strip off pointer casts and all-zero GEPs.
Definition: Value.cpp:571
StringRef getName() const
Return a constant reference to the value&#39;s name.
Definition: Value.cpp:224
#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:591
static bool doit(const Value &Val)
Definition: Value.h:763
raw_ostream & operator<<(raw_ostream &OS, const APInt &I)
Definition: APInt.h:2023
void mutateType(Type *Ty)
Mutate the type of this Value to be of the specified type.
Definition: Value.h:609
~Value()
Value&#39;s destructor should be virtual by design, but that would require that Value and all of its subc...
Definition: Value.cpp:73
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:553
Base class for aggregate constants (with operands).
Definition: Constants.h:386
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:784
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:207
static bool doit(const Value &Val)
Definition: Value.h:838
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:820
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:449
bool operator==(uint64_t V1, const APInt &V2)
Definition: APInt.h:1951
const Value * stripInBoundsConstantOffsets() const
Strip off pointer casts and all-constant inbounds GEPs.
Definition: Value.cpp:575
void replaceUsesExceptBlockAddr(Value *New)
replaceUsesExceptBlockAddr - Go through the uses list for this definition and make each use point to ...
Definition: Value.cpp:468
Base class for constants with no operands.
Definition: Constants.h:58
Value * operator=(Value *RHS)
Definition: Value.h:682
bool use_empty() const
Definition: Value.h:328
static bool doit(const Value &Val)
Definition: Value.h:808
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:770
user_iterator user_end()
Definition: Value.h:389