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 // FIXME: This does not handle cyclic function local metadata.
137 const Function *F = 0, *NewF = 0;
138 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
139 if (Value *V = N->getOperand(i)) {
140 if (MDNode *MD = dyn_cast<MDNode>(V))
141 NewF = assertLocalFunction(MD);
143 NewF = getFunctionForValue(V);
148 assert((NewF == 0 || F == NewF) &&"inconsistent function-local metadata");
154 // getFunction - If this metadata is function-local and recursively has a
155 // function-local operand, return the first such operand's parent function.
156 // Otherwise, return null. getFunction() should not be used for performance-
157 // critical code because it recursively visits all the MDNode's operands.
158 const Function *MDNode::getFunction() const {
160 return assertLocalFunction(this);
162 if (!isFunctionLocal()) return NULL;
163 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
164 if (const Function *F = getFunctionForValue(getOperand(i)))
169 // destroy - Delete this node. Only when there are no uses.
170 void MDNode::destroy() {
171 setValueSubclassData(getSubclassDataFromValue() | DestroyFlag);
172 // Placement delete, the free the memory.
177 /// isFunctionLocalValue - Return true if this is a value that would require a
178 /// function-local MDNode.
179 static bool isFunctionLocalValue(Value *V) {
180 return isa<Instruction>(V) || isa<Argument>(V) || isa<BasicBlock>(V) ||
181 (isa<MDNode>(V) && cast<MDNode>(V)->isFunctionLocal());
184 MDNode *MDNode::getMDNode(LLVMContext &Context, Value *const *Vals,
185 unsigned NumVals, FunctionLocalness FL,
187 LLVMContextImpl *pImpl = Context.pImpl;
188 bool isFunctionLocal = false;
191 for (unsigned i = 0; i != NumVals; ++i) {
194 if (isFunctionLocalValue(V)) {
195 isFunctionLocal = true;
201 isFunctionLocal = false;
204 isFunctionLocal = true;
209 for (unsigned i = 0; i != NumVals; ++i)
210 ID.AddPointer(Vals[i]);
211 ID.AddBoolean(isFunctionLocal);
216 if ((N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint)))
222 // Coallocate space for the node and Operands together, then placement new.
223 void *Ptr = malloc(sizeof(MDNode)+NumVals*sizeof(MDNodeOperand));
224 N = new (Ptr) MDNode(Context, Vals, NumVals, isFunctionLocal);
226 // InsertPoint will have been set by the FindNodeOrInsertPos call.
227 pImpl->MDNodeSet.InsertNode(N, InsertPoint);
232 MDNode *MDNode::get(LLVMContext &Context, Value*const* Vals, unsigned NumVals) {
233 return getMDNode(Context, Vals, NumVals, FL_Unknown);
236 MDNode *MDNode::getWhenValsUnresolved(LLVMContext &Context, Value *const *Vals,
237 unsigned NumVals, bool isFunctionLocal) {
238 return getMDNode(Context, Vals, NumVals, isFunctionLocal ? FL_Yes : FL_No);
241 MDNode *MDNode::getIfExists(LLVMContext &Context, Value *const *Vals,
243 return getMDNode(Context, Vals, NumVals, FL_Unknown, false);
246 /// getOperand - Return specified operand.
247 Value *MDNode::getOperand(unsigned i) const {
248 return *getOperandPtr(const_cast<MDNode*>(this), i);
251 void MDNode::Profile(FoldingSetNodeID &ID) const {
252 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
253 ID.AddPointer(getOperand(i));
254 ID.AddBoolean(isFunctionLocal());
257 void MDNode::setIsNotUniqued() {
258 setValueSubclassData(getSubclassDataFromValue() | NotUniquedBit);
259 LLVMContextImpl *pImpl = getType()->getContext().pImpl;
260 pImpl->NonUniquedMDNodes.insert(this);
263 // Replace value from this node's operand list.
264 void MDNode::replaceOperand(MDNodeOperand *Op, Value *To) {
267 // If is possible that someone did GV->RAUW(inst), replacing a global variable
268 // with an instruction or some other function-local object. If this is a
269 // non-function-local MDNode, it can't point to a function-local object.
270 // Handle this case by implicitly dropping the MDNode reference to null.
271 // Likewise if the MDNode is function-local but for a different function.
272 if (To && isFunctionLocalValue(To)) {
273 if (!isFunctionLocal())
276 const Function *F = getFunction();
277 const Function *FV = getFunctionForValue(To);
278 // Metadata can be function-local without having an associated function.
279 // So only consider functions to have changed if non-null.
280 if (F && FV && F != FV)
288 // Update the operand.
291 // If this node is already not being uniqued (because one of the operands
292 // already went to null), then there is nothing else to do here.
293 if (isNotUniqued()) return;
295 LLVMContextImpl *pImpl = getType()->getContext().pImpl;
297 // Remove "this" from the context map. FoldingSet doesn't have to reprofile
298 // this node to remove it, so we don't care what state the operands are in.
299 pImpl->MDNodeSet.RemoveNode(this);
301 // If we are dropping an argument to null, we choose to not unique the MDNode
302 // anymore. This commonly occurs during destruction, and uniquing these
303 // brings little reuse.
309 // Now that the node is out of the folding set, get ready to reinsert it.
310 // First, check to see if another node with the same operands already exists
311 // in the set. If it doesn't exist, this returns the position to insert it.
315 MDNode *N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
318 N->replaceAllUsesWith(this);
320 N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
321 assert(N == 0 && "shouldn't be in the map now!"); (void)N;
324 // InsertPoint will have been set by the FindNodeOrInsertPos call.
325 pImpl->MDNodeSet.InsertNode(this, InsertPoint);
328 //===----------------------------------------------------------------------===//
329 // NamedMDNode implementation.
333 // SymbolTableListTraits specialization for MDSymbolTable.
334 void ilist_traits<NamedMDNode>
335 ::addNodeToList(NamedMDNode *N) {
336 assert(N->getParent() == 0 && "Value already in a container!!");
337 Module *Owner = getListOwner();
339 MDSymbolTable &ST = Owner->getMDSymbolTable();
340 ST.insert(N->getName(), N);
343 void ilist_traits<NamedMDNode>::removeNodeFromList(NamedMDNode *N) {
345 Module *Owner = getListOwner();
346 MDSymbolTable &ST = Owner->getMDSymbolTable();
347 ST.remove(N->getName());
351 static SmallVector<WeakVH, 4> &getNMDOps(void *Operands) {
352 return *(SmallVector<WeakVH, 4>*)Operands;
355 NamedMDNode::NamedMDNode(LLVMContext &C, const Twine &N,
357 unsigned NumMDs, Module *ParentModule)
358 : Value(Type::getMetadataTy(C), Value::NamedMDNodeVal), Parent(0) {
360 Operands = new SmallVector<WeakVH, 4>();
362 SmallVector<WeakVH, 4> &Node = getNMDOps(Operands);
363 for (unsigned i = 0; i != NumMDs; ++i)
364 Node.push_back(WeakVH(MDs[i]));
367 ParentModule->getNamedMDList().push_back(this);
370 NamedMDNode *NamedMDNode::Create(const NamedMDNode *NMD, Module *M) {
371 assert(NMD && "Invalid source NamedMDNode!");
372 SmallVector<MDNode *, 4> Elems;
373 Elems.reserve(NMD->getNumOperands());
375 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i)
376 Elems.push_back(NMD->getOperand(i));
377 return new NamedMDNode(NMD->getContext(), NMD->getName().data(),
378 Elems.data(), Elems.size(), M);
381 NamedMDNode::~NamedMDNode() {
383 delete &getNMDOps(Operands);
386 /// getNumOperands - Return number of NamedMDNode operands.
387 unsigned NamedMDNode::getNumOperands() const {
388 return (unsigned)getNMDOps(Operands).size();
391 /// getOperand - Return specified operand.
392 MDNode *NamedMDNode::getOperand(unsigned i) const {
393 assert(i < getNumOperands() && "Invalid Operand number!");
394 return dyn_cast_or_null<MDNode>(getNMDOps(Operands)[i]);
397 /// addOperand - Add metadata Operand.
398 void NamedMDNode::addOperand(MDNode *M) {
399 getNMDOps(Operands).push_back(WeakVH(M));
402 /// eraseFromParent - Drop all references and remove the node from parent
404 void NamedMDNode::eraseFromParent() {
405 getParent()->getNamedMDList().erase(this);
408 /// dropAllReferences - Remove all uses and clear node vector.
409 void NamedMDNode::dropAllReferences() {
410 getNMDOps(Operands).clear();
413 /// setName - Set the name of this named metadata.
414 void NamedMDNode::setName(const Twine &NewName) {
415 assert (!NewName.isTriviallyEmpty() && "Invalid named metadata name!");
417 SmallString<256> NameData;
418 StringRef NameRef = NewName.toStringRef(NameData);
420 // Name isn't changing?
421 if (getName() == NameRef)
424 Name = NameRef.str();
426 Parent->getMDSymbolTable().insert(NameRef, this);
429 /// getName - Return a constant reference to this named metadata's name.
430 StringRef NamedMDNode::getName() const {
431 return StringRef(Name);
434 //===----------------------------------------------------------------------===//
435 // Instruction Metadata method implementations.
438 void Instruction::setMetadata(const char *Kind, MDNode *Node) {
439 if (Node == 0 && !hasMetadata()) return;
440 setMetadata(getContext().getMDKindID(Kind), Node);
443 MDNode *Instruction::getMetadataImpl(const char *Kind) const {
444 return getMetadataImpl(getContext().getMDKindID(Kind));
447 void Instruction::setDbgMetadata(MDNode *Node) {
448 DbgLoc = DebugLoc::getFromDILocation(Node);
451 /// setMetadata - Set the metadata of of the specified kind to the specified
452 /// node. This updates/replaces metadata if already present, or removes it if
454 void Instruction::setMetadata(unsigned KindID, MDNode *Node) {
455 if (Node == 0 && !hasMetadata()) return;
457 // Handle 'dbg' as a special case since it is not stored in the hash table.
458 if (KindID == LLVMContext::MD_dbg) {
459 DbgLoc = DebugLoc::getFromDILocation(Node);
463 // Handle the case when we're adding/updating metadata on an instruction.
465 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
466 assert(!Info.empty() == hasMetadataHashEntry() &&
467 "HasMetadata bit is wonked");
469 setHasMetadataHashEntry(true);
471 // Handle replacement of an existing value.
472 for (unsigned i = 0, e = Info.size(); i != e; ++i)
473 if (Info[i].first == KindID) {
474 Info[i].second = Node;
479 // No replacement, just add it to the list.
480 Info.push_back(std::make_pair(KindID, Node));
484 // Otherwise, we're removing metadata from an instruction.
485 assert(hasMetadataHashEntry() &&
486 getContext().pImpl->MetadataStore.count(this) &&
487 "HasMetadata bit out of date!");
488 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
490 // Common case is removing the only entry.
491 if (Info.size() == 1 && Info[0].first == KindID) {
492 getContext().pImpl->MetadataStore.erase(this);
493 setHasMetadataHashEntry(false);
497 // Handle removal of an existing value.
498 for (unsigned i = 0, e = Info.size(); i != e; ++i)
499 if (Info[i].first == KindID) {
500 Info[i] = Info.back();
502 assert(!Info.empty() && "Removing last entry should be handled above");
505 // Otherwise, removing an entry that doesn't exist on the instruction.
508 MDNode *Instruction::getMetadataImpl(unsigned KindID) const {
509 // Handle 'dbg' as a special case since it is not stored in the hash table.
510 if (KindID == LLVMContext::MD_dbg)
511 return DbgLoc.getAsMDNode(getContext());
513 if (!hasMetadataHashEntry()) return 0;
515 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
516 assert(!Info.empty() && "bit out of sync with hash table");
518 for (LLVMContextImpl::MDMapTy::iterator I = Info.begin(), E = Info.end();
520 if (I->first == KindID)
525 void Instruction::getAllMetadataImpl(SmallVectorImpl<std::pair<unsigned,
526 MDNode*> > &Result) const {
529 // Handle 'dbg' as a special case since it is not stored in the hash table.
530 if (!DbgLoc.isUnknown()) {
531 Result.push_back(std::make_pair((unsigned)LLVMContext::MD_dbg,
532 DbgLoc.getAsMDNode(getContext())));
533 if (!hasMetadataHashEntry()) return;
536 assert(hasMetadataHashEntry() &&
537 getContext().pImpl->MetadataStore.count(this) &&
538 "Shouldn't have called this");
539 const LLVMContextImpl::MDMapTy &Info =
540 getContext().pImpl->MetadataStore.find(this)->second;
541 assert(!Info.empty() && "Shouldn't have called this");
543 Result.append(Info.begin(), Info.end());
545 // Sort the resulting array so it is stable.
546 if (Result.size() > 1)
547 array_pod_sort(Result.begin(), Result.end());
551 getAllMetadataOtherThanDebugLocImpl(SmallVectorImpl<std::pair<unsigned,
552 MDNode*> > &Result) const {
554 assert(hasMetadataHashEntry() &&
555 getContext().pImpl->MetadataStore.count(this) &&
556 "Shouldn't have called this");
557 const LLVMContextImpl::MDMapTy &Info =
558 getContext().pImpl->MetadataStore.find(this)->second;
559 assert(!Info.empty() && "Shouldn't have called this");
561 Result.append(Info.begin(), Info.end());
563 // Sort the resulting array so it is stable.
564 if (Result.size() > 1)
565 array_pod_sort(Result.begin(), Result.end());
569 /// removeAllMetadata - Remove all metadata from this instruction.
570 void Instruction::removeAllMetadata() {
571 assert(hasMetadata() && "Caller should check");
573 if (hasMetadataHashEntry()) {
574 getContext().pImpl->MetadataStore.erase(this);
575 setHasMetadataHashEntry(false);