1 //===-- Metadata.cpp - Implement Metadata classes -------------------------===//
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 //===----------------------------------------------------------------------===//
10 // This file implements the Metadata classes.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Metadata.h"
15 #include "LLVMContextImpl.h"
16 #include "llvm/LLVMContext.h"
17 #include "llvm/Module.h"
18 #include "llvm/Instruction.h"
19 #include "llvm/ADT/DenseMap.h"
20 #include "llvm/ADT/StringMap.h"
21 #include "llvm/ADT/SmallString.h"
22 #include "SymbolTableListTraitsImpl.h"
23 #include "llvm/Support/ValueHandle.h"
26 //===----------------------------------------------------------------------===//
27 // MDString implementation.
30 MDString::MDString(LLVMContext &C, StringRef S)
31 : Value(Type::getMetadataTy(C), Value::MDStringVal), Str(S) {}
33 MDString *MDString::get(LLVMContext &Context, StringRef Str) {
34 LLVMContextImpl *pImpl = Context.pImpl;
35 StringMapEntry<MDString *> &Entry =
36 pImpl->MDStringCache.GetOrCreateValue(Str);
37 MDString *&S = Entry.getValue();
38 if (!S) S = new MDString(Context, Entry.getKey());
42 //===----------------------------------------------------------------------===//
43 // MDNodeOperand implementation.
46 // Use CallbackVH to hold MDNode operands.
48 class MDNodeOperand : public CallbackVH {
51 MDNodeOperand(Value *V, MDNode *P) : CallbackVH(V), Parent(P) {}
58 virtual void deleted();
59 virtual void allUsesReplacedWith(Value *NV);
61 } // end namespace llvm.
64 void MDNodeOperand::deleted() {
65 Parent->replaceOperand(this, 0);
68 void MDNodeOperand::allUsesReplacedWith(Value *NV) {
69 Parent->replaceOperand(this, NV);
74 //===----------------------------------------------------------------------===//
75 // MDNode implementation.
78 /// getOperandPtr - Helper function to get the MDNodeOperand's coallocated on
79 /// the end of the MDNode.
80 static MDNodeOperand *getOperandPtr(MDNode *N, unsigned Op) {
81 assert(Op < N->getNumOperands() && "Invalid operand number");
82 return reinterpret_cast<MDNodeOperand*>(N+1)+Op;
85 MDNode::MDNode(LLVMContext &C, Value *const *Vals, unsigned NumVals,
87 : Value(Type::getMetadataTy(C), Value::MDNodeVal) {
88 NumOperands = NumVals;
91 setValueSubclassData(getSubclassDataFromValue() | FunctionLocalBit);
93 // Initialize the operand list, which is co-allocated on the end of the node.
94 for (MDNodeOperand *Op = getOperandPtr(this, 0), *E = Op+NumOperands;
95 Op != E; ++Op, ++Vals)
96 new (Op) MDNodeOperand(*Vals, this);
100 /// ~MDNode - Destroy MDNode.
102 assert((getSubclassDataFromValue() & DestroyFlag) != 0 &&
103 "Not being destroyed through destroy()?");
104 LLVMContextImpl *pImpl = getType()->getContext().pImpl;
105 if (isNotUniqued()) {
106 pImpl->NonUniquedMDNodes.erase(this);
108 pImpl->MDNodeSet.RemoveNode(this);
111 // Destroy the operands.
112 for (MDNodeOperand *Op = getOperandPtr(this, 0), *E = Op+NumOperands;
114 Op->~MDNodeOperand();
117 static const Function *getFunctionForValue(Value *V) {
119 if (Instruction *I = dyn_cast<Instruction>(V)) {
120 BasicBlock *BB = I->getParent();
121 return BB ? BB->getParent() : 0;
123 if (Argument *A = dyn_cast<Argument>(V))
124 return A->getParent();
125 if (BasicBlock *BB = dyn_cast<BasicBlock>(V))
126 return BB->getParent();
127 if (MDNode *MD = dyn_cast<MDNode>(V))
128 return MD->getFunction();
133 static const Function *assertLocalFunction(const MDNode *N) {
134 if (!N->isFunctionLocal()) return 0;
136 const Function *F = 0, *NewF = 0;
137 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
138 if (Value *V = N->getOperand(i)) {
139 if (MDNode *MD = dyn_cast<MDNode>(V))
140 NewF = assertLocalFunction(MD);
142 NewF = getFunctionForValue(V);
147 assert((NewF == 0 || F == NewF) &&"inconsistent function-local metadata");
153 // getFunction - If this metadata is function-local and recursively has a
154 // function-local operand, return the first such operand's parent function.
155 // Otherwise, return null. getFunction() should not be used for performance-
156 // critical code because it recursively visits all the MDNode's operands.
157 const Function *MDNode::getFunction() const {
159 return assertLocalFunction(this);
161 if (!isFunctionLocal()) return NULL;
162 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
163 if (const Function *F = getFunctionForValue(getOperand(i)))
168 // destroy - Delete this node. Only when there are no uses.
169 void MDNode::destroy() {
170 setValueSubclassData(getSubclassDataFromValue() | DestroyFlag);
171 // Placement delete, the free the memory.
176 /// isFunctionLocalValue - Return true if this is a value that would require a
177 /// function-local MDNode.
178 static bool isFunctionLocalValue(Value *V) {
179 return isa<Instruction>(V) || isa<Argument>(V) || isa<BasicBlock>(V) ||
180 (isa<MDNode>(V) && cast<MDNode>(V)->isFunctionLocal());
183 MDNode *MDNode::getMDNode(LLVMContext &Context, Value *const *Vals,
184 unsigned NumVals, FunctionLocalness FL,
186 LLVMContextImpl *pImpl = Context.pImpl;
187 bool isFunctionLocal = false;
190 for (unsigned i = 0; i != NumVals; ++i) {
193 if (isFunctionLocalValue(V)) {
194 isFunctionLocal = true;
200 isFunctionLocal = false;
203 isFunctionLocal = true;
208 for (unsigned i = 0; i != NumVals; ++i)
209 ID.AddPointer(Vals[i]);
210 ID.AddBoolean(isFunctionLocal);
215 if ((N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint)))
221 // Coallocate space for the node and Operands together, then placement new.
222 void *Ptr = malloc(sizeof(MDNode)+NumVals*sizeof(MDNodeOperand));
223 N = new (Ptr) MDNode(Context, Vals, NumVals, isFunctionLocal);
225 // InsertPoint will have been set by the FindNodeOrInsertPos call.
226 pImpl->MDNodeSet.InsertNode(N, InsertPoint);
231 MDNode *MDNode::get(LLVMContext &Context, Value*const* Vals, unsigned NumVals) {
232 return getMDNode(Context, Vals, NumVals, FL_Unknown);
235 MDNode *MDNode::getWhenValsUnresolved(LLVMContext &Context, Value *const *Vals,
236 unsigned NumVals, bool isFunctionLocal) {
237 return getMDNode(Context, Vals, NumVals, isFunctionLocal ? FL_Yes : FL_No);
240 MDNode *MDNode::getIfExists(LLVMContext &Context, Value *const *Vals,
242 return getMDNode(Context, Vals, NumVals, FL_Unknown, false);
245 /// getOperand - Return specified operand.
246 Value *MDNode::getOperand(unsigned i) const {
247 return *getOperandPtr(const_cast<MDNode*>(this), i);
250 void MDNode::Profile(FoldingSetNodeID &ID) const {
251 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
252 ID.AddPointer(getOperand(i));
253 ID.AddBoolean(isFunctionLocal());
256 void MDNode::setIsNotUniqued() {
257 setValueSubclassData(getSubclassDataFromValue() | NotUniquedBit);
258 LLVMContextImpl *pImpl = getType()->getContext().pImpl;
259 pImpl->NonUniquedMDNodes.insert(this);
262 // Replace value from this node's operand list.
263 void MDNode::replaceOperand(MDNodeOperand *Op, Value *To) {
266 // If is possible that someone did GV->RAUW(inst), replacing a global variable
267 // with an instruction or some other function-local object. If this is a
268 // non-function-local MDNode, it can't point to a function-local object.
269 // Handle this case by implicitly dropping the MDNode reference to null.
270 // Likewise if the MDNode is function-local but for a different function.
271 if (To && isFunctionLocalValue(To)) {
272 if (!isFunctionLocal())
275 const Function *F = getFunction();
276 const Function *FV = getFunctionForValue(To);
277 // Metadata can be function-local without having an associated function.
278 // So only consider functions to have changed if non-null.
279 if (F && FV && F != FV)
287 // Update the operand.
290 // If this node is already not being uniqued (because one of the operands
291 // already went to null), then there is nothing else to do here.
292 if (isNotUniqued()) return;
294 LLVMContextImpl *pImpl = getType()->getContext().pImpl;
296 // Remove "this" from the context map. FoldingSet doesn't have to reprofile
297 // this node to remove it, so we don't care what state the operands are in.
298 pImpl->MDNodeSet.RemoveNode(this);
300 // If we are dropping an argument to null, we choose to not unique the MDNode
301 // anymore. This commonly occurs during destruction, and uniquing these
302 // brings little reuse.
308 // Now that the node is out of the folding set, get ready to reinsert it.
309 // First, check to see if another node with the same operands already exists
310 // in the set. If it doesn't exist, this returns the position to insert it.
314 MDNode *N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
317 N->replaceAllUsesWith(this);
319 N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
320 assert(N == 0 && "shouldn't be in the map now!"); (void)N;
323 // InsertPoint will have been set by the FindNodeOrInsertPos call.
324 pImpl->MDNodeSet.InsertNode(this, InsertPoint);
327 //===----------------------------------------------------------------------===//
328 // NamedMDNode implementation.
332 // SymbolTableListTraits specialization for MDSymbolTable.
333 void ilist_traits<NamedMDNode>
334 ::addNodeToList(NamedMDNode *N) {
335 assert(N->getParent() == 0 && "Value already in a container!!");
336 Module *Owner = getListOwner();
338 MDSymbolTable &ST = Owner->getMDSymbolTable();
339 ST.insert(N->getName(), N);
342 void ilist_traits<NamedMDNode>::removeNodeFromList(NamedMDNode *N) {
344 Module *Owner = getListOwner();
345 MDSymbolTable &ST = Owner->getMDSymbolTable();
346 ST.remove(N->getName());
350 static SmallVector<WeakVH, 4> &getNMDOps(void *Operands) {
351 return *(SmallVector<WeakVH, 4>*)Operands;
354 NamedMDNode::NamedMDNode(LLVMContext &C, const Twine &N,
356 unsigned NumMDs, Module *ParentModule)
357 : Value(Type::getMetadataTy(C), Value::NamedMDNodeVal), Parent(0) {
359 Operands = new SmallVector<WeakVH, 4>();
361 SmallVector<WeakVH, 4> &Node = getNMDOps(Operands);
362 for (unsigned i = 0; i != NumMDs; ++i)
363 Node.push_back(WeakVH(MDs[i]));
366 ParentModule->getNamedMDList().push_back(this);
369 NamedMDNode *NamedMDNode::Create(const NamedMDNode *NMD, Module *M) {
370 assert(NMD && "Invalid source NamedMDNode!");
371 SmallVector<MDNode *, 4> Elems;
372 Elems.reserve(NMD->getNumOperands());
374 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i)
375 Elems.push_back(NMD->getOperand(i));
376 return new NamedMDNode(NMD->getContext(), NMD->getName().data(),
377 Elems.data(), Elems.size(), M);
380 NamedMDNode::~NamedMDNode() {
382 delete &getNMDOps(Operands);
385 /// getNumOperands - Return number of NamedMDNode operands.
386 unsigned NamedMDNode::getNumOperands() const {
387 return (unsigned)getNMDOps(Operands).size();
390 /// getOperand - Return specified operand.
391 MDNode *NamedMDNode::getOperand(unsigned i) const {
392 assert(i < getNumOperands() && "Invalid Operand number!");
393 return dyn_cast_or_null<MDNode>(getNMDOps(Operands)[i]);
396 /// addOperand - Add metadata Operand.
397 void NamedMDNode::addOperand(MDNode *M) {
398 getNMDOps(Operands).push_back(WeakVH(M));
401 /// eraseFromParent - Drop all references and remove the node from parent
403 void NamedMDNode::eraseFromParent() {
404 getParent()->getNamedMDList().erase(this);
407 /// dropAllReferences - Remove all uses and clear node vector.
408 void NamedMDNode::dropAllReferences() {
409 getNMDOps(Operands).clear();
412 /// setName - Set the name of this named metadata.
413 void NamedMDNode::setName(const Twine &NewName) {
414 assert (!NewName.isTriviallyEmpty() && "Invalid named metadata name!");
416 SmallString<256> NameData;
417 StringRef NameRef = NewName.toStringRef(NameData);
419 // Name isn't changing?
420 if (getName() == NameRef)
423 Name = NameRef.str();
425 Parent->getMDSymbolTable().insert(NameRef, this);
428 /// getName - Return a constant reference to this named metadata's name.
429 StringRef NamedMDNode::getName() const {
430 return StringRef(Name);
433 //===----------------------------------------------------------------------===//
434 // Instruction Metadata method implementations.
437 void Instruction::setMetadata(const char *Kind, MDNode *Node) {
438 if (Node == 0 && !hasMetadata()) return;
439 setMetadata(getContext().getMDKindID(Kind), Node);
442 MDNode *Instruction::getMetadataImpl(const char *Kind) const {
443 return getMetadataImpl(getContext().getMDKindID(Kind));
446 void Instruction::setDbgMetadata(MDNode *Node) {
447 DbgLoc = DebugLoc::getFromDILocation(Node);
450 /// setMetadata - Set the metadata of of the specified kind to the specified
451 /// node. This updates/replaces metadata if already present, or removes it if
453 void Instruction::setMetadata(unsigned KindID, MDNode *Node) {
454 if (Node == 0 && !hasMetadata()) return;
456 // Handle 'dbg' as a special case since it is not stored in the hash table.
457 if (KindID == LLVMContext::MD_dbg) {
458 DbgLoc = DebugLoc::getFromDILocation(Node);
462 // Handle the case when we're adding/updating metadata on an instruction.
464 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
465 assert(!Info.empty() == hasMetadataHashEntry() &&
466 "HasMetadata bit is wonked");
468 setHasMetadataHashEntry(true);
470 // Handle replacement of an existing value.
471 for (unsigned i = 0, e = Info.size(); i != e; ++i)
472 if (Info[i].first == KindID) {
473 Info[i].second = Node;
478 // No replacement, just add it to the list.
479 Info.push_back(std::make_pair(KindID, Node));
483 // Otherwise, we're removing metadata from an instruction.
484 assert(hasMetadataHashEntry() &&
485 getContext().pImpl->MetadataStore.count(this) &&
486 "HasMetadata bit out of date!");
487 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
489 // Common case is removing the only entry.
490 if (Info.size() == 1 && Info[0].first == KindID) {
491 getContext().pImpl->MetadataStore.erase(this);
492 setHasMetadataHashEntry(false);
496 // Handle removal of an existing value.
497 for (unsigned i = 0, e = Info.size(); i != e; ++i)
498 if (Info[i].first == KindID) {
499 Info[i] = Info.back();
501 assert(!Info.empty() && "Removing last entry should be handled above");
504 // Otherwise, removing an entry that doesn't exist on the instruction.
507 MDNode *Instruction::getMetadataImpl(unsigned KindID) const {
508 // Handle 'dbg' as a special case since it is not stored in the hash table.
509 if (KindID == LLVMContext::MD_dbg)
510 return DbgLoc.getAsMDNode(getContext());
512 if (!hasMetadataHashEntry()) return 0;
514 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
515 assert(!Info.empty() && "bit out of sync with hash table");
517 for (LLVMContextImpl::MDMapTy::iterator I = Info.begin(), E = Info.end();
519 if (I->first == KindID)
524 void Instruction::getAllMetadataImpl(SmallVectorImpl<std::pair<unsigned,
525 MDNode*> > &Result) const {
528 // Handle 'dbg' as a special case since it is not stored in the hash table.
529 if (!DbgLoc.isUnknown()) {
530 Result.push_back(std::make_pair((unsigned)LLVMContext::MD_dbg,
531 DbgLoc.getAsMDNode(getContext())));
532 if (!hasMetadataHashEntry()) return;
535 assert(hasMetadataHashEntry() &&
536 getContext().pImpl->MetadataStore.count(this) &&
537 "Shouldn't have called this");
538 const LLVMContextImpl::MDMapTy &Info =
539 getContext().pImpl->MetadataStore.find(this)->second;
540 assert(!Info.empty() && "Shouldn't have called this");
542 Result.append(Info.begin(), Info.end());
544 // Sort the resulting array so it is stable.
545 if (Result.size() > 1)
546 array_pod_sort(Result.begin(), Result.end());
550 getAllMetadataOtherThanDebugLocImpl(SmallVectorImpl<std::pair<unsigned,
551 MDNode*> > &Result) const {
553 assert(hasMetadataHashEntry() &&
554 getContext().pImpl->MetadataStore.count(this) &&
555 "Shouldn't have called this");
556 const LLVMContextImpl::MDMapTy &Info =
557 getContext().pImpl->MetadataStore.find(this)->second;
558 assert(!Info.empty() && "Shouldn't have called this");
560 Result.append(Info.begin(), Info.end());
562 // Sort the resulting array so it is stable.
563 if (Result.size() > 1)
564 array_pod_sort(Result.begin(), Result.end());
568 /// removeAllMetadata - Remove all metadata from this instruction.
569 void Instruction::removeAllMetadata() {
570 assert(hasMetadata() && "Caller should check");
572 if (hasMetadataHashEntry()) {
573 getContext().pImpl->MetadataStore.erase(this);
574 setHasMetadataHashEntry(false);