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/Type.h"
21 #include "llvm/ADT/FoldingSet.h"
22 #include "llvm/ADT/SmallVector.h"
23 #include "llvm/ADT/ilist_node.h"
24 #include "llvm/Support/ValueHandle.h"
30 class MetadataContextImpl;
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)
59 : MetadataBase(Type::getMetadataTy(C), Value::MDStringVal), Str(S) {}
62 static MDString *get(LLVMContext &Context, StringRef Str);
63 static MDString *get(LLVMContext &Context, const char *Str);
65 StringRef getString() const { return Str; }
67 unsigned getLength() const { return (unsigned)Str.size(); }
69 typedef StringRef::iterator iterator;
71 /// begin() - Pointer to the first byte of the string.
73 iterator begin() const { return Str.begin(); }
75 /// end() - Pointer to one byte past the end of the string.
77 iterator end() const { return Str.end(); }
79 /// Methods for support type inquiry through isa, cast, and dyn_cast:
80 static inline bool classof(const MDString *) { return true; }
81 static bool classof(const Value *V) {
82 return V->getValueID() == MDStringVal;
86 //===----------------------------------------------------------------------===//
87 /// MDNode - a tuple of other values.
88 /// These contain a list of the values that represent the metadata.
89 /// MDNode is always unnamed.
90 class MDNode : public MetadataBase, public FoldingSetNode {
91 MDNode(const MDNode &); // DO NOT IMPLEMENT
93 friend class ElementVH;
94 // Use CallbackVH to hold MDNode elements.
95 struct ElementVH : public CallbackVH {
98 ElementVH(Value *V, MDNode *P) : CallbackVH(V), Parent(P) {}
101 virtual void deleted() {
102 Parent->replaceElement(this->operator Value*(), 0);
105 virtual void allUsesReplacedWith(Value *NV) {
106 Parent->replaceElement(this->operator Value*(), NV);
109 // Replace each instance of F from the element list of this node with T.
110 void replaceElement(Value *F, Value *T);
114 Function *LocalFunction;
117 explicit MDNode(LLVMContext &C, Value *const *Vals, unsigned NumVals,
118 Function *LocalFunc = NULL);
120 // Constructors and destructors.
121 static MDNode *get(LLVMContext &Context,
122 Value *const *Vals, unsigned NumVals,
123 Function *LocalFunction = NULL);
125 /// ~MDNode - Destroy MDNode.
128 /// getElement - Return specified element.
129 Value *getElement(unsigned i) const {
130 assert(i < getNumElements() && "Invalid element number!");
134 /// getNumElements - Return number of MDNode elements.
135 unsigned getNumElements() const { return NodeSize; }
137 /// isFunctionLocal - Return whether MDNode is local to a function.
138 bool isFunctionLocal() const { return LocalFunction; }
140 /// Profile - calculate a unique identifier for this MDNode to collapse
142 void Profile(FoldingSetNodeID &ID) const;
144 /// Methods for support type inquiry through isa, cast, and dyn_cast:
145 static inline bool classof(const MDNode *) { return true; }
146 static bool classof(const Value *V) {
147 return V->getValueID() == MDNodeVal;
151 //===----------------------------------------------------------------------===//
152 /// NamedMDNode - a tuple of other metadata.
153 /// NamedMDNode is always named. All NamedMDNode element has a type of metadata.
154 template<typename ValueSubClass, typename ItemParentClass>
155 class SymbolTableListTraits;
157 class NamedMDNode : public MetadataBase, public ilist_node<NamedMDNode> {
158 friend class SymbolTableListTraits<NamedMDNode, Module>;
159 friend class LLVMContextImpl;
161 NamedMDNode(const NamedMDNode &); // DO NOT IMPLEMENT
164 SmallVector<TrackingVH<MetadataBase>, 4> Node;
166 void setParent(Module *M) { Parent = M; }
168 explicit NamedMDNode(LLVMContext &C, const Twine &N, MetadataBase*const *Vals,
169 unsigned NumVals, Module *M = 0);
171 static NamedMDNode *Create(LLVMContext &C, const Twine &N,
172 MetadataBase *const *MDs,
173 unsigned NumMDs, Module *M = 0) {
174 return new NamedMDNode(C, N, MDs, NumMDs, M);
177 static NamedMDNode *Create(const NamedMDNode *NMD, Module *M = 0);
179 /// eraseFromParent - Drop all references and remove the node from parent
181 void eraseFromParent();
183 /// dropAllReferences - Remove all uses and clear node vector.
184 void dropAllReferences();
186 /// ~NamedMDNode - Destroy NamedMDNode.
189 /// getParent - Get the module that holds this named metadata collection.
190 inline Module *getParent() { return Parent; }
191 inline const Module *getParent() const { return Parent; }
193 /// getElement - Return specified element.
194 MetadataBase *getElement(unsigned i) const {
195 assert(i < getNumElements() && "Invalid element number!");
199 /// getNumElements - Return number of NamedMDNode elements.
200 unsigned getNumElements() const {
201 return (unsigned)Node.size();
204 /// addElement - Add metadata element.
205 void addElement(MetadataBase *M) {
206 Node.push_back(TrackingVH<MetadataBase>(M));
209 typedef SmallVectorImpl<TrackingVH<MetadataBase> >::iterator elem_iterator;
210 typedef SmallVectorImpl<TrackingVH<MetadataBase> >::const_iterator
212 bool elem_empty() const { return Node.empty(); }
213 const_elem_iterator elem_begin() const { return Node.begin(); }
214 const_elem_iterator elem_end() const { return Node.end(); }
215 elem_iterator elem_begin() { return Node.begin(); }
216 elem_iterator elem_end() { return Node.end(); }
218 /// Methods for support type inquiry through isa, cast, and dyn_cast:
219 static inline bool classof(const NamedMDNode *) { return true; }
220 static bool classof(const Value *V) {
221 return V->getValueID() == NamedMDNodeVal;
225 //===----------------------------------------------------------------------===//
226 /// MetadataContext -
227 /// MetadataContext handles uniquing and assignment of IDs for custom metadata
228 /// types. Custom metadata handler names do not contain spaces. And the name
229 /// must start with an alphabet. The regular expression used to check name
230 /// is [a-zA-Z$._][a-zA-Z$._0-9]*
231 class MetadataContext {
233 MetadataContext(MetadataContext&);
234 void operator=(MetadataContext&);
236 MetadataContextImpl *const pImpl;
241 /// registerMDKind - Register a new metadata kind and return its ID.
242 /// A metadata kind can be registered only once.
243 unsigned registerMDKind(StringRef Name);
245 /// getMDKind - Return metadata kind. If the requested metadata kind
246 /// is not registered then return 0.
247 unsigned getMDKind(StringRef Name) const;
249 /// isValidName - Return true if Name is a valid custom metadata handler name.
250 static bool isValidName(StringRef Name);
252 /// getMD - Get the metadata of given kind attached to an Instruction.
253 /// If the metadata is not found then return 0.
254 MDNode *getMD(unsigned Kind, const Instruction *Inst);
256 /// getMDs - Get the metadata attached to an Instruction.
257 void getMDs(const Instruction *Inst,
258 SmallVectorImpl<std::pair<unsigned, TrackingVH<MDNode> > > &MDs) const;
260 /// addMD - Attach the metadata of given kind to an Instruction.
261 void addMD(unsigned Kind, MDNode *Node, Instruction *Inst);
263 /// removeMD - Remove metadata of given kind attached with an instuction.
264 void removeMD(unsigned Kind, Instruction *Inst);
266 /// removeAllMetadata - Remove all metadata attached with an instruction.
267 void removeAllMetadata(Instruction *Inst);
269 /// copyMD - If metadata is attached with Instruction In1 then attach
270 /// the same metadata to In2.
271 void copyMD(Instruction *In1, Instruction *In2);
273 /// getHandlerNames - Populate client supplied smallvector using custom
274 /// metadata name and ID.
275 void getHandlerNames(SmallVectorImpl<std::pair<unsigned, StringRef> >&) const;
277 /// ValueIsDeleted - This handler is used to update metadata store
278 /// when a value is deleted.
279 void ValueIsDeleted(const Value *) {}
280 void ValueIsDeleted(Instruction *Inst);
281 void ValueIsRAUWd(Value *V1, Value *V2);
283 /// ValueIsCloned - This handler is used to update metadata store
284 /// when In1 is cloned to create In2.
285 void ValueIsCloned(const Instruction *In1, Instruction *In2);
288 } // end llvm namespace