1 //===-- llvm/Metadata.h - Metadata definitions ------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 /// This file contains the declarations for metadata subclasses.
12 /// They represent the different flavors of metadata that live in LLVM.
14 //===----------------------------------------------------------------------===//
16 #ifndef LLVM_METADATA_H
17 #define LLVM_METADATA_H
19 #include "llvm/Value.h"
20 #include "llvm/ADT/FoldingSet.h"
21 #include "llvm/ADT/ilist_node.h"
28 class MetadataContextImpl;
29 template <typename T> class SmallVectorImpl;
30 template<class PtrType, unsigned SmallSize> class SmallPtrSet;
32 //===----------------------------------------------------------------------===//
33 // MetadataBase - A base class for MDNode, MDString and NamedMDNode.
34 class MetadataBase : public Value {
36 MetadataBase(const Type *Ty, unsigned scid)
41 /// Methods for support type inquiry through isa, cast, and dyn_cast:
42 static inline bool classof(const MetadataBase *) { return true; }
43 static bool classof(const Value *V) {
44 return V->getValueID() == MDStringVal || V->getValueID() == MDNodeVal
45 || V->getValueID() == NamedMDNodeVal;
49 //===----------------------------------------------------------------------===//
50 /// MDString - a single uniqued string.
51 /// These are used to efficiently contain a byte sequence for metadata.
52 /// MDString is always unnamd.
53 class MDString : public MetadataBase {
54 MDString(const MDString &); // DO NOT IMPLEMENT
58 explicit MDString(LLVMContext &C, StringRef S);
61 static MDString *get(LLVMContext &Context, StringRef Str);
62 static MDString *get(LLVMContext &Context, const char *Str);
64 StringRef getString() const { return Str; }
66 unsigned getLength() const { return (unsigned)Str.size(); }
68 typedef StringRef::iterator iterator;
70 /// begin() - Pointer to the first byte of the string.
72 iterator begin() const { return Str.begin(); }
74 /// end() - Pointer to one byte past the end of the string.
76 iterator end() const { return Str.end(); }
78 /// Methods for support type inquiry through isa, cast, and dyn_cast:
79 static inline bool classof(const MDString *) { return true; }
80 static bool classof(const Value *V) {
81 return V->getValueID() == MDStringVal;
88 //===----------------------------------------------------------------------===//
89 /// MDNode - a tuple of other values.
90 /// These contain a list of the values that represent the metadata.
91 /// MDNode is always unnamed.
92 class MDNode : public MetadataBase, public FoldingSetNode {
93 MDNode(const MDNode &); // DO NOT IMPLEMENT
95 friend class MDNodeElement;
97 static const unsigned short FunctionLocalBit = 1;
99 // Replace each instance of F from the element list of this node with T.
100 void replaceElement(Value *F, Value *T);
102 MDNodeElement *Operands;
103 unsigned NumOperands;
106 explicit MDNode(LLVMContext &C, Value *const *Vals, unsigned NumVals,
107 bool isFunctionLocal);
109 // Constructors and destructors.
110 static MDNode *get(LLVMContext &Context, Value *const *Vals, unsigned NumVals,
111 bool isFunctionLocal = false);
113 /// ~MDNode - Destroy MDNode.
116 /// getElement - Return specified element.
117 Value *getElement(unsigned i) const;
119 /// getNumElements - Return number of MDNode elements.
120 unsigned getNumElements() const { return NumOperands; }
122 /// isFunctionLocal - Return whether MDNode is local to a function.
123 /// Note: MDNodes are designated as function-local when created, and keep
124 /// that designation even if their operands are modified to no longer
125 /// refer to function-local IR.
126 bool isFunctionLocal() const { return SubclassData & FunctionLocalBit; }
128 /// getLocalFunction - Return false if MDNode's recursive function-localness
129 /// is invalid (local to more than one function). Return true otherwise.
130 /// If MDNode has one function to which it is local, set LocalFunction to that
132 bool getLocalFunction(Function *LocalFunction,
133 SmallPtrSet<MDNode *, 32> *VisitedMDNodes = NULL);
135 /// Profile - calculate a unique identifier for this MDNode to collapse
137 void Profile(FoldingSetNodeID &ID) const;
139 /// Methods for support type inquiry through isa, cast, and dyn_cast:
140 static inline bool classof(const MDNode *) { return true; }
141 static bool classof(const Value *V) {
142 return V->getValueID() == MDNodeVal;
146 //===----------------------------------------------------------------------===//
147 /// NamedMDNode - a tuple of other metadata.
148 /// NamedMDNode is always named. All NamedMDNode element has a type of metadata.
149 template<typename ValueSubClass, typename ItemParentClass>
150 class SymbolTableListTraits;
152 class NamedMDNode : public MetadataBase, public ilist_node<NamedMDNode> {
153 friend class SymbolTableListTraits<NamedMDNode, Module>;
154 friend class LLVMContextImpl;
156 NamedMDNode(const NamedMDNode &); // DO NOT IMPLEMENT
159 void *Operands; // SmallVector<TrackingVH<MetadataBase>, 4>
161 void setParent(Module *M) { Parent = M; }
163 explicit NamedMDNode(LLVMContext &C, const Twine &N, MetadataBase*const *Vals,
164 unsigned NumVals, Module *M = 0);
166 static NamedMDNode *Create(LLVMContext &C, const Twine &N,
167 MetadataBase *const *MDs,
168 unsigned NumMDs, Module *M = 0) {
169 return new NamedMDNode(C, N, MDs, NumMDs, M);
172 static NamedMDNode *Create(const NamedMDNode *NMD, Module *M = 0);
174 /// eraseFromParent - Drop all references and remove the node from parent
176 void eraseFromParent();
178 /// dropAllReferences - Remove all uses and clear node vector.
179 void dropAllReferences();
181 /// ~NamedMDNode - Destroy NamedMDNode.
184 /// getParent - Get the module that holds this named metadata collection.
185 inline Module *getParent() { return Parent; }
186 inline const Module *getParent() const { return Parent; }
188 /// getElement - Return specified element.
189 MetadataBase *getElement(unsigned i) const;
191 /// getNumElements - Return number of NamedMDNode elements.
192 unsigned getNumElements() const;
194 /// addElement - Add metadata element.
195 void addElement(MetadataBase *M);
197 /// Methods for support type inquiry through isa, cast, and dyn_cast:
198 static inline bool classof(const NamedMDNode *) { return true; }
199 static bool classof(const Value *V) {
200 return V->getValueID() == NamedMDNodeVal;
204 //===----------------------------------------------------------------------===//
205 /// MetadataContext -
206 /// MetadataContext handles uniquing and assignment of IDs for custom metadata
207 /// types. Custom metadata handler names do not contain spaces. And the name
208 /// must start with an alphabet. The regular expression used to check name
209 /// is [a-zA-Z$._][a-zA-Z$._0-9]*
210 class MetadataContext {
212 MetadataContext(MetadataContext&);
213 void operator=(MetadataContext&);
215 MetadataContextImpl *const pImpl;
220 /// registerMDKind - Register a new metadata kind and return its ID.
221 /// A metadata kind can be registered only once.
222 unsigned registerMDKind(StringRef Name);
224 /// getMDKind - Return metadata kind. If the requested metadata kind
225 /// is not registered then return 0.
226 unsigned getMDKind(StringRef Name) const;
228 /// isValidName - Return true if Name is a valid custom metadata handler name.
229 static bool isValidName(StringRef Name);
231 /// getMD - Get the metadata of given kind attached to an Instruction.
232 /// If the metadata is not found then return 0.
233 MDNode *getMD(unsigned Kind, const Instruction *Inst);
235 /// getMDs - Get the metadata attached to an Instruction.
236 void getMDs(const Instruction *Inst,
237 SmallVectorImpl<std::pair<unsigned, MDNode*> > &MDs) const;
239 /// addMD - Attach the metadata of given kind to an Instruction.
240 void addMD(unsigned Kind, MDNode *Node, Instruction *Inst);
242 /// removeMD - Remove metadata of given kind attached with an instuction.
243 void removeMD(unsigned Kind, Instruction *Inst);
245 /// removeAllMetadata - Remove all metadata attached with an instruction.
246 void removeAllMetadata(Instruction *Inst);
248 /// copyMD - If metadata is attached with Instruction In1 then attach
249 /// the same metadata to In2.
250 void copyMD(Instruction *In1, Instruction *In2);
252 /// getHandlerNames - Populate client supplied smallvector using custom
253 /// metadata name and ID.
254 void getHandlerNames(SmallVectorImpl<std::pair<unsigned, StringRef> >&) const;
256 /// ValueIsDeleted - This handler is used to update metadata store
257 /// when a value is deleted.
258 void ValueIsDeleted(const Value *) {}
259 void ValueIsDeleted(Instruction *Inst);
260 void ValueIsRAUWd(Value *V1, Value *V2);
262 /// ValueIsCloned - This handler is used to update metadata store
263 /// when In1 is cloned to create In2.
264 void ValueIsCloned(const Instruction *In1, Instruction *In2);
267 } // end llvm namespace