1 //===--- Pointer.h - Types for the constexpr VM -----------------*- C++ -*-===//
9 // Defines the classes responsible for pointer tracking.
31 class Pointer;  variable
35 /// A pointer to a memory block, live or dead.
39 class Pointer {
45   Pointer() {}  in Pointer()  function
46   Pointer(Block *B);
47   Pointer(const Pointer &P);
48   Pointer(Pointer &&P);
49   ~Pointer();
51   void operator=(const Pointer &P);
52   void operator=(Pointer &&P);
54   /// Converts the pointer to an APValue.
57   /// Offsets a pointer inside an array.
58   Pointer atIndex(unsigned Idx) const {  in atIndex()
60       return Pointer(Pointee, RootPtrMark, getDeclDesc()->getSize());  in atIndex()
66     return Pointer(Pointee, Base, Base + Off);  in atIndex()
69   /// Creates a pointer to a field.
70   Pointer atField(unsigned Off) const {  in atField()
72     return Pointer(Pointee, Field, Field);  in atField()
75   /// Restricts the scope of an array element pointer.
76   Pointer narrow() const {  in narrow()
81     // Pointer to an array of base types - enter block.  in narrow()
83       return Pointer(Pointee, 0, Offset == 0 ? Offset : PastEndMark);  in narrow()
85     // Pointer is one past end - magic offset marks that.  in narrow()
87       return Pointer(Pointee, Base, PastEndMark);  in narrow()
90     // descriptors. If Offset != Base, then the pointer already points to  in narrow()
91     // an element and there is nothing to do. Otherwise, the pointer is  in narrow()
96       return Pointer(Pointee, Base, Offset + sizeof(InitMap *));  in narrow()
99     // Pointer is to a field or array element - enter it.  in narrow()
101       return Pointer(Pointee, Offset, Offset);  in narrow()
108     return Pointer(Pointee, NewBase, NewBase);  in narrow()
111   /// Expands a pointer to the containing array, undoing narrowing.
112   Pointer expand() const {  in expand()
114       // Revert to an outer one-past-end pointer.  in expand()
120       return Pointer(Pointee, Base, Base + getSize() + Adjust);  in expand()
129       return Pointer(Pointee, RootPtrMark, 0);  in expand()
136     return Pointer(Pointee, Next, Offset);  in expand()
139   /// Checks if the pointer is null.
141   /// Checks if the pointer is live.
150   /// Returns a pointer to the object of which this pointer is a field.
151   Pointer getBase() const {  in getBase()
154       return Pointer(Pointee, Base, 0);  in getBase()
158     return Pointer(Pointee, NewBase, NewBase);  in getBase()
161   Pointer getArray() const {  in getArray()
164       return Pointer(Pointee, Base, 0);  in getArray()
167     return Pointer(Pointee, Base, Base);  in getArray()
213   /// Checks if the pointer points to an array.
215   /// Pointer points directly to a block.
276   /// Checks if the pointer is an out-of-bounds element pointer.
279   /// Dereferences the pointer, if it's live.
281     assert(isLive() && "Invalid pointer");  in deref()
298   static bool hasSameBase(const Pointer &A, const Pointer &B);
300   static bool hasSameArray(const Pointer &A, const Pointer &B);
302   /// Prints the pointer.
316   Pointer(Block *Pointee, unsigned Base, unsigned Offset);
323     assert(Offset != 0 && "Not a nested pointer");  in getDescriptor()
327   /// Returns a reference to the pointer which stores the initialization map.
332   /// The block the pointer is pointing to.
339   /// Previous link in the pointer chain.
340   Pointer *Prev = nullptr;
341   /// Next link in the pointer chain.
342   Pointer *Next = nullptr;
345 inline llvm::raw_ostream &operator<<(llvm::raw_ostream &OS, const Pointer &P) {