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/LeakDetector.h"
24 #include "llvm/Support/ValueHandle.h"
27 //===----------------------------------------------------------------------===//
28 // MDString implementation.
31 MDString::MDString(LLVMContext &C, StringRef S)
32 : Value(Type::getMetadataTy(C), Value::MDStringVal), Str(S) {}
34 MDString *MDString::get(LLVMContext &Context, StringRef Str) {
35 LLVMContextImpl *pImpl = Context.pImpl;
36 StringMapEntry<MDString *> &Entry =
37 pImpl->MDStringCache.GetOrCreateValue(Str);
38 MDString *&S = Entry.getValue();
39 if (!S) S = new MDString(Context, Entry.getKey());
43 //===----------------------------------------------------------------------===//
44 // MDNodeOperand implementation.
47 // Use CallbackVH to hold MDNode operands.
49 class MDNodeOperand : public CallbackVH {
52 MDNodeOperand(Value *V, MDNode *P) : CallbackVH(V), Parent(P) {}
59 virtual void deleted();
60 virtual void allUsesReplacedWith(Value *NV);
62 } // end namespace llvm.
65 void MDNodeOperand::deleted() {
66 Parent->replaceOperand(this, 0);
69 void MDNodeOperand::allUsesReplacedWith(Value *NV) {
70 Parent->replaceOperand(this, NV);
75 //===----------------------------------------------------------------------===//
76 // MDNode implementation.
79 /// getOperandPtr - Helper function to get the MDNodeOperand's coallocated on
80 /// the end of the MDNode.
81 static MDNodeOperand *getOperandPtr(MDNode *N, unsigned Op) {
82 // Use <= instead of < to permit a one-past-the-end address.
83 assert(Op <= N->getNumOperands() && "Invalid operand number");
84 return reinterpret_cast<MDNodeOperand*>(N+1)+Op;
87 MDNode::MDNode(LLVMContext &C, Value *const *Vals, unsigned NumVals,
89 : Value(Type::getMetadataTy(C), Value::MDNodeVal) {
90 NumOperands = NumVals;
93 setValueSubclassData(getSubclassDataFromValue() | FunctionLocalBit);
95 // Initialize the operand list, which is co-allocated on the end of the node.
96 for (MDNodeOperand *Op = getOperandPtr(this, 0), *E = Op+NumOperands;
97 Op != E; ++Op, ++Vals)
98 new (Op) MDNodeOperand(*Vals, this);
102 /// ~MDNode - Destroy MDNode.
104 assert((getSubclassDataFromValue() & DestroyFlag) != 0 &&
105 "Not being destroyed through destroy()?");
106 LLVMContextImpl *pImpl = getType()->getContext().pImpl;
107 if (isNotUniqued()) {
108 pImpl->NonUniquedMDNodes.erase(this);
110 pImpl->MDNodeSet.RemoveNode(this);
113 // Destroy the operands.
114 for (MDNodeOperand *Op = getOperandPtr(this, 0), *E = Op+NumOperands;
116 Op->~MDNodeOperand();
119 static const Function *getFunctionForValue(Value *V) {
121 if (Instruction *I = dyn_cast<Instruction>(V)) {
122 BasicBlock *BB = I->getParent();
123 return BB ? BB->getParent() : 0;
125 if (Argument *A = dyn_cast<Argument>(V))
126 return A->getParent();
127 if (BasicBlock *BB = dyn_cast<BasicBlock>(V))
128 return BB->getParent();
129 if (MDNode *MD = dyn_cast<MDNode>(V))
130 return MD->getFunction();
135 static const Function *assertLocalFunction(const MDNode *N) {
136 if (!N->isFunctionLocal()) return 0;
138 // FIXME: This does not handle cyclic function local metadata.
139 const Function *F = 0, *NewF = 0;
140 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
141 if (Value *V = N->getOperand(i)) {
142 if (MDNode *MD = dyn_cast<MDNode>(V))
143 NewF = assertLocalFunction(MD);
145 NewF = getFunctionForValue(V);
150 assert((NewF == 0 || F == NewF) &&"inconsistent function-local metadata");
156 // getFunction - If this metadata is function-local and recursively has a
157 // function-local operand, return the first such operand's parent function.
158 // Otherwise, return null. getFunction() should not be used for performance-
159 // critical code because it recursively visits all the MDNode's operands.
160 const Function *MDNode::getFunction() const {
162 return assertLocalFunction(this);
164 if (!isFunctionLocal()) return NULL;
165 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
166 if (const Function *F = getFunctionForValue(getOperand(i)))
171 // destroy - Delete this node. Only when there are no uses.
172 void MDNode::destroy() {
173 setValueSubclassData(getSubclassDataFromValue() | DestroyFlag);
174 // Placement delete, the free the memory.
179 /// isFunctionLocalValue - Return true if this is a value that would require a
180 /// function-local MDNode.
181 static bool isFunctionLocalValue(Value *V) {
182 return isa<Instruction>(V) || isa<Argument>(V) || isa<BasicBlock>(V) ||
183 (isa<MDNode>(V) && cast<MDNode>(V)->isFunctionLocal());
186 MDNode *MDNode::getMDNode(LLVMContext &Context, Value *const *Vals,
187 unsigned NumVals, FunctionLocalness FL,
189 LLVMContextImpl *pImpl = Context.pImpl;
191 // Add all the operand pointers. Note that we don't have to add the
192 // isFunctionLocal bit because that's implied by the operands.
194 for (unsigned i = 0; i != NumVals; ++i)
195 ID.AddPointer(Vals[i]);
200 if ((N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint)))
203 bool isFunctionLocal = false;
206 for (unsigned i = 0; i != NumVals; ++i) {
209 if (isFunctionLocalValue(V)) {
210 isFunctionLocal = true;
216 isFunctionLocal = false;
219 isFunctionLocal = true;
223 // Coallocate space for the node and Operands together, then placement new.
224 void *Ptr = malloc(sizeof(MDNode)+NumVals*sizeof(MDNodeOperand));
225 N = new (Ptr) MDNode(Context, Vals, NumVals, isFunctionLocal);
227 // InsertPoint will have been set by the FindNodeOrInsertPos call.
228 pImpl->MDNodeSet.InsertNode(N, InsertPoint);
233 MDNode *MDNode::get(LLVMContext &Context, Value*const* Vals, unsigned NumVals) {
234 return getMDNode(Context, Vals, NumVals, FL_Unknown);
237 MDNode *MDNode::getWhenValsUnresolved(LLVMContext &Context, Value *const *Vals,
238 unsigned NumVals, bool isFunctionLocal) {
239 return getMDNode(Context, Vals, NumVals, isFunctionLocal ? FL_Yes : FL_No);
242 MDNode *MDNode::getIfExists(LLVMContext &Context, Value *const *Vals,
244 return getMDNode(Context, Vals, NumVals, FL_Unknown, false);
247 MDNode *MDNode::getTemporary(LLVMContext &Context, Value *const *Vals,
249 MDNode *N = (MDNode *)malloc(sizeof(MDNode)+NumVals*sizeof(MDNodeOperand));
250 N = new (N) MDNode(Context, Vals, NumVals, FL_No);
251 N->setValueSubclassData(N->getSubclassDataFromValue() |
253 LeakDetector::addGarbageObject(N);
257 void MDNode::deleteTemporary(MDNode *N) {
258 assert(N->use_empty() && "Temporary MDNode has uses!");
259 assert(!N->getContext().pImpl->MDNodeSet.RemoveNode(N) &&
260 "Deleting a non-temporary uniqued node!");
261 assert(!N->getContext().pImpl->NonUniquedMDNodes.erase(N) &&
262 "Deleting a non-temporary non-uniqued node!");
263 assert((N->getSubclassDataFromValue() & NotUniquedBit) &&
264 "Temporary MDNode does not have NotUniquedBit set!");
265 assert((N->getSubclassDataFromValue() & DestroyFlag) == 0 &&
266 "Temporary MDNode has DestroyFlag set!");
267 LeakDetector::removeGarbageObject(N);
271 /// getOperand - Return specified operand.
272 Value *MDNode::getOperand(unsigned i) const {
273 return *getOperandPtr(const_cast<MDNode*>(this), i);
276 void MDNode::Profile(FoldingSetNodeID &ID) const {
277 // Add all the operand pointers. Note that we don't have to add the
278 // isFunctionLocal bit because that's implied by the operands.
279 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
280 ID.AddPointer(getOperand(i));
283 void MDNode::setIsNotUniqued() {
284 setValueSubclassData(getSubclassDataFromValue() | NotUniquedBit);
285 LLVMContextImpl *pImpl = getType()->getContext().pImpl;
286 pImpl->NonUniquedMDNodes.insert(this);
289 // Replace value from this node's operand list.
290 void MDNode::replaceOperand(MDNodeOperand *Op, Value *To) {
293 // If is possible that someone did GV->RAUW(inst), replacing a global variable
294 // with an instruction or some other function-local object. If this is a
295 // non-function-local MDNode, it can't point to a function-local object.
296 // Handle this case by implicitly dropping the MDNode reference to null.
297 // Likewise if the MDNode is function-local but for a different function.
298 if (To && isFunctionLocalValue(To)) {
299 if (!isFunctionLocal())
302 const Function *F = getFunction();
303 const Function *FV = getFunctionForValue(To);
304 // Metadata can be function-local without having an associated function.
305 // So only consider functions to have changed if non-null.
306 if (F && FV && F != FV)
314 // Update the operand.
317 // If this node is already not being uniqued (because one of the operands
318 // already went to null), then there is nothing else to do here.
319 if (isNotUniqued()) return;
321 LLVMContextImpl *pImpl = getType()->getContext().pImpl;
323 // Remove "this" from the context map. FoldingSet doesn't have to reprofile
324 // this node to remove it, so we don't care what state the operands are in.
325 pImpl->MDNodeSet.RemoveNode(this);
327 // If we are dropping an argument to null, we choose to not unique the MDNode
328 // anymore. This commonly occurs during destruction, and uniquing these
329 // brings little reuse.
335 // Now that the node is out of the folding set, get ready to reinsert it.
336 // First, check to see if another node with the same operands already exists
337 // in the set. If it doesn't exist, this returns the position to insert it.
341 MDNode *N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
344 N->replaceAllUsesWith(this);
346 N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
347 assert(N == 0 && "shouldn't be in the map now!"); (void)N;
350 // InsertPoint will have been set by the FindNodeOrInsertPos call.
351 pImpl->MDNodeSet.InsertNode(this, InsertPoint);
354 //===----------------------------------------------------------------------===//
355 // NamedMDNode implementation.
358 static SmallVector<TrackingVH<MDNode>, 4> &getNMDOps(void *Operands) {
359 return *(SmallVector<TrackingVH<MDNode>, 4>*)Operands;
362 NamedMDNode::NamedMDNode(const Twine &N)
363 : Name(N.str()), Parent(0),
364 Operands(new SmallVector<TrackingVH<MDNode>, 4>()) {
367 NamedMDNode::~NamedMDNode() {
369 delete &getNMDOps(Operands);
372 /// getNumOperands - Return number of NamedMDNode operands.
373 unsigned NamedMDNode::getNumOperands() const {
374 return (unsigned)getNMDOps(Operands).size();
377 /// getOperand - Return specified operand.
378 MDNode *NamedMDNode::getOperand(unsigned i) const {
379 assert(i < getNumOperands() && "Invalid Operand number!");
380 return dyn_cast<MDNode>(&*getNMDOps(Operands)[i]);
383 /// addOperand - Add metadata Operand.
384 void NamedMDNode::addOperand(MDNode *M) {
385 getNMDOps(Operands).push_back(TrackingVH<MDNode>(M));
388 /// eraseFromParent - Drop all references and remove the node from parent
390 void NamedMDNode::eraseFromParent() {
391 getParent()->eraseNamedMetadata(this);
394 /// dropAllReferences - Remove all uses and clear node vector.
395 void NamedMDNode::dropAllReferences() {
396 getNMDOps(Operands).clear();
399 /// getName - Return a constant reference to this named metadata's name.
400 StringRef NamedMDNode::getName() const {
401 return StringRef(Name);
404 //===----------------------------------------------------------------------===//
405 // Instruction Metadata method implementations.
408 void Instruction::setMetadata(const char *Kind, MDNode *Node) {
409 if (Node == 0 && !hasMetadata()) return;
410 setMetadata(getContext().getMDKindID(Kind), Node);
413 MDNode *Instruction::getMetadataImpl(const char *Kind) const {
414 return getMetadataImpl(getContext().getMDKindID(Kind));
417 /// setMetadata - Set the metadata of of the specified kind to the specified
418 /// node. This updates/replaces metadata if already present, or removes it if
420 void Instruction::setMetadata(unsigned KindID, MDNode *Node) {
421 if (Node == 0 && !hasMetadata()) return;
423 // Handle 'dbg' as a special case since it is not stored in the hash table.
424 if (KindID == LLVMContext::MD_dbg) {
425 DbgLoc = DebugLoc::getFromDILocation(Node);
429 // Handle the case when we're adding/updating metadata on an instruction.
431 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
432 assert(!Info.empty() == hasMetadataHashEntry() &&
433 "HasMetadata bit is wonked");
435 setHasMetadataHashEntry(true);
437 // Handle replacement of an existing value.
438 for (unsigned i = 0, e = Info.size(); i != e; ++i)
439 if (Info[i].first == KindID) {
440 Info[i].second = Node;
445 // No replacement, just add it to the list.
446 Info.push_back(std::make_pair(KindID, Node));
450 // Otherwise, we're removing metadata from an instruction.
451 assert(hasMetadataHashEntry() &&
452 getContext().pImpl->MetadataStore.count(this) &&
453 "HasMetadata bit out of date!");
454 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
456 // Common case is removing the only entry.
457 if (Info.size() == 1 && Info[0].first == KindID) {
458 getContext().pImpl->MetadataStore.erase(this);
459 setHasMetadataHashEntry(false);
463 // Handle removal of an existing value.
464 for (unsigned i = 0, e = Info.size(); i != e; ++i)
465 if (Info[i].first == KindID) {
466 Info[i] = Info.back();
468 assert(!Info.empty() && "Removing last entry should be handled above");
471 // Otherwise, removing an entry that doesn't exist on the instruction.
474 MDNode *Instruction::getMetadataImpl(unsigned KindID) const {
475 // Handle 'dbg' as a special case since it is not stored in the hash table.
476 if (KindID == LLVMContext::MD_dbg)
477 return DbgLoc.getAsMDNode(getContext());
479 if (!hasMetadataHashEntry()) return 0;
481 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
482 assert(!Info.empty() && "bit out of sync with hash table");
484 for (LLVMContextImpl::MDMapTy::iterator I = Info.begin(), E = Info.end();
486 if (I->first == KindID)
491 void Instruction::getAllMetadataImpl(SmallVectorImpl<std::pair<unsigned,
492 MDNode*> > &Result) const {
495 // Handle 'dbg' as a special case since it is not stored in the hash table.
496 if (!DbgLoc.isUnknown()) {
497 Result.push_back(std::make_pair((unsigned)LLVMContext::MD_dbg,
498 DbgLoc.getAsMDNode(getContext())));
499 if (!hasMetadataHashEntry()) return;
502 assert(hasMetadataHashEntry() &&
503 getContext().pImpl->MetadataStore.count(this) &&
504 "Shouldn't have called this");
505 const LLVMContextImpl::MDMapTy &Info =
506 getContext().pImpl->MetadataStore.find(this)->second;
507 assert(!Info.empty() && "Shouldn't have called this");
509 Result.append(Info.begin(), Info.end());
511 // Sort the resulting array so it is stable.
512 if (Result.size() > 1)
513 array_pod_sort(Result.begin(), Result.end());
517 getAllMetadataOtherThanDebugLocImpl(SmallVectorImpl<std::pair<unsigned,
518 MDNode*> > &Result) const {
520 assert(hasMetadataHashEntry() &&
521 getContext().pImpl->MetadataStore.count(this) &&
522 "Shouldn't have called this");
523 const LLVMContextImpl::MDMapTy &Info =
524 getContext().pImpl->MetadataStore.find(this)->second;
525 assert(!Info.empty() && "Shouldn't have called this");
527 Result.append(Info.begin(), Info.end());
529 // Sort the resulting array so it is stable.
530 if (Result.size() > 1)
531 array_pod_sort(Result.begin(), Result.end());
535 /// clearMetadataHashEntries - Clear all hashtable-based metadata from
536 /// this instruction.
537 void Instruction::clearMetadataHashEntries() {
538 assert(hasMetadataHashEntry() && "Caller should check");
539 getContext().pImpl->MetadataStore.erase(this);
540 setHasMetadataHashEntry(false);