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;
190 bool isFunctionLocal = false;
193 for (unsigned i = 0; i != NumVals; ++i) {
196 if (isFunctionLocalValue(V)) {
197 isFunctionLocal = true;
203 isFunctionLocal = false;
206 isFunctionLocal = true;
211 for (unsigned i = 0; i != NumVals; ++i)
212 ID.AddPointer(Vals[i]);
213 ID.AddBoolean(isFunctionLocal);
218 if ((N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint)))
224 // Coallocate space for the node and Operands together, then placement new.
225 void *Ptr = malloc(sizeof(MDNode)+NumVals*sizeof(MDNodeOperand));
226 N = new (Ptr) MDNode(Context, Vals, NumVals, isFunctionLocal);
228 // InsertPoint will have been set by the FindNodeOrInsertPos call.
229 pImpl->MDNodeSet.InsertNode(N, InsertPoint);
234 MDNode *MDNode::get(LLVMContext &Context, Value*const* Vals, unsigned NumVals) {
235 return getMDNode(Context, Vals, NumVals, FL_Unknown);
238 MDNode *MDNode::getWhenValsUnresolved(LLVMContext &Context, Value *const *Vals,
239 unsigned NumVals, bool isFunctionLocal) {
240 return getMDNode(Context, Vals, NumVals, isFunctionLocal ? FL_Yes : FL_No);
243 MDNode *MDNode::getIfExists(LLVMContext &Context, Value *const *Vals,
245 return getMDNode(Context, Vals, NumVals, FL_Unknown, false);
248 MDNode *MDNode::getTemporary(LLVMContext &Context, Value *const *Vals,
250 MDNode *N = (MDNode *)malloc(sizeof(MDNode)+NumVals*sizeof(MDNodeOperand));
251 N = new (N) MDNode(Context, Vals, NumVals, FL_No);
252 N->setValueSubclassData(N->getSubclassDataFromValue() |
254 LeakDetector::addGarbageObject(N);
258 void MDNode::deleteTemporary(MDNode *N) {
259 assert(N->use_empty() && "Temporary MDNode has uses!");
260 assert((N->getSubclassDataFromValue() & NotUniquedBit) &&
261 "Temporary MDNode does not have NotUniquedBit set!");
262 assert((N->getSubclassDataFromValue() & DestroyFlag) == 0 &&
263 "Temporary MDNode does has DestroyFlag set!");
264 N->setValueSubclassData(N->getSubclassDataFromValue() |
266 LeakDetector::removeGarbageObject(N);
270 /// getOperand - Return specified operand.
271 Value *MDNode::getOperand(unsigned i) const {
272 return *getOperandPtr(const_cast<MDNode*>(this), i);
275 void MDNode::Profile(FoldingSetNodeID &ID) const {
276 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
277 ID.AddPointer(getOperand(i));
278 ID.AddBoolean(isFunctionLocal());
281 void MDNode::setIsNotUniqued() {
282 setValueSubclassData(getSubclassDataFromValue() | NotUniquedBit);
283 LLVMContextImpl *pImpl = getType()->getContext().pImpl;
284 pImpl->NonUniquedMDNodes.insert(this);
287 // Replace value from this node's operand list.
288 void MDNode::replaceOperand(MDNodeOperand *Op, Value *To) {
291 // If is possible that someone did GV->RAUW(inst), replacing a global variable
292 // with an instruction or some other function-local object. If this is a
293 // non-function-local MDNode, it can't point to a function-local object.
294 // Handle this case by implicitly dropping the MDNode reference to null.
295 // Likewise if the MDNode is function-local but for a different function.
296 if (To && isFunctionLocalValue(To)) {
297 if (!isFunctionLocal())
300 const Function *F = getFunction();
301 const Function *FV = getFunctionForValue(To);
302 // Metadata can be function-local without having an associated function.
303 // So only consider functions to have changed if non-null.
304 if (F && FV && F != FV)
312 // Update the operand.
315 // If this node is already not being uniqued (because one of the operands
316 // already went to null), then there is nothing else to do here.
317 if (isNotUniqued()) return;
319 LLVMContextImpl *pImpl = getType()->getContext().pImpl;
321 // Remove "this" from the context map. FoldingSet doesn't have to reprofile
322 // this node to remove it, so we don't care what state the operands are in.
323 pImpl->MDNodeSet.RemoveNode(this);
325 // If we are dropping an argument to null, we choose to not unique the MDNode
326 // anymore. This commonly occurs during destruction, and uniquing these
327 // brings little reuse.
333 // Now that the node is out of the folding set, get ready to reinsert it.
334 // First, check to see if another node with the same operands already exists
335 // in the set. If it doesn't exist, this returns the position to insert it.
339 MDNode *N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
342 N->replaceAllUsesWith(this);
344 N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
345 assert(N == 0 && "shouldn't be in the map now!"); (void)N;
348 // InsertPoint will have been set by the FindNodeOrInsertPos call.
349 pImpl->MDNodeSet.InsertNode(this, InsertPoint);
352 //===----------------------------------------------------------------------===//
353 // NamedMDNode implementation.
356 static SmallVector<TrackingVH<MDNode>, 4> &getNMDOps(void *Operands) {
357 return *(SmallVector<TrackingVH<MDNode>, 4>*)Operands;
360 NamedMDNode::NamedMDNode(const Twine &N)
361 : Name(N.str()), Parent(0),
362 Operands(new SmallVector<TrackingVH<MDNode>, 4>()) {
365 NamedMDNode::~NamedMDNode() {
367 delete &getNMDOps(Operands);
370 /// getNumOperands - Return number of NamedMDNode operands.
371 unsigned NamedMDNode::getNumOperands() const {
372 return (unsigned)getNMDOps(Operands).size();
375 /// getOperand - Return specified operand.
376 MDNode *NamedMDNode::getOperand(unsigned i) const {
377 assert(i < getNumOperands() && "Invalid Operand number!");
378 return dyn_cast<MDNode>(&*getNMDOps(Operands)[i]);
381 /// addOperand - Add metadata Operand.
382 void NamedMDNode::addOperand(MDNode *M) {
383 getNMDOps(Operands).push_back(TrackingVH<MDNode>(M));
386 /// eraseFromParent - Drop all references and remove the node from parent
388 void NamedMDNode::eraseFromParent() {
389 getParent()->eraseNamedMetadata(this);
392 /// dropAllReferences - Remove all uses and clear node vector.
393 void NamedMDNode::dropAllReferences() {
394 getNMDOps(Operands).clear();
397 /// getName - Return a constant reference to this named metadata's name.
398 StringRef NamedMDNode::getName() const {
399 return StringRef(Name);
402 //===----------------------------------------------------------------------===//
403 // Instruction Metadata method implementations.
406 void Instruction::setMetadata(const char *Kind, MDNode *Node) {
407 if (Node == 0 && !hasMetadata()) return;
408 setMetadata(getContext().getMDKindID(Kind), Node);
411 MDNode *Instruction::getMetadataImpl(const char *Kind) const {
412 return getMetadataImpl(getContext().getMDKindID(Kind));
415 /// setMetadata - Set the metadata of of the specified kind to the specified
416 /// node. This updates/replaces metadata if already present, or removes it if
418 void Instruction::setMetadata(unsigned KindID, MDNode *Node) {
419 if (Node == 0 && !hasMetadata()) return;
421 // Handle 'dbg' as a special case since it is not stored in the hash table.
422 if (KindID == LLVMContext::MD_dbg) {
423 DbgLoc = DebugLoc::getFromDILocation(Node);
427 // Handle the case when we're adding/updating metadata on an instruction.
429 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
430 assert(!Info.empty() == hasMetadataHashEntry() &&
431 "HasMetadata bit is wonked");
433 setHasMetadataHashEntry(true);
435 // Handle replacement of an existing value.
436 for (unsigned i = 0, e = Info.size(); i != e; ++i)
437 if (Info[i].first == KindID) {
438 Info[i].second = Node;
443 // No replacement, just add it to the list.
444 Info.push_back(std::make_pair(KindID, Node));
448 // Otherwise, we're removing metadata from an instruction.
449 assert(hasMetadataHashEntry() &&
450 getContext().pImpl->MetadataStore.count(this) &&
451 "HasMetadata bit out of date!");
452 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
454 // Common case is removing the only entry.
455 if (Info.size() == 1 && Info[0].first == KindID) {
456 getContext().pImpl->MetadataStore.erase(this);
457 setHasMetadataHashEntry(false);
461 // Handle removal of an existing value.
462 for (unsigned i = 0, e = Info.size(); i != e; ++i)
463 if (Info[i].first == KindID) {
464 Info[i] = Info.back();
466 assert(!Info.empty() && "Removing last entry should be handled above");
469 // Otherwise, removing an entry that doesn't exist on the instruction.
472 MDNode *Instruction::getMetadataImpl(unsigned KindID) const {
473 // Handle 'dbg' as a special case since it is not stored in the hash table.
474 if (KindID == LLVMContext::MD_dbg)
475 return DbgLoc.getAsMDNode(getContext());
477 if (!hasMetadataHashEntry()) return 0;
479 LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
480 assert(!Info.empty() && "bit out of sync with hash table");
482 for (LLVMContextImpl::MDMapTy::iterator I = Info.begin(), E = Info.end();
484 if (I->first == KindID)
489 void Instruction::getAllMetadataImpl(SmallVectorImpl<std::pair<unsigned,
490 MDNode*> > &Result) const {
493 // Handle 'dbg' as a special case since it is not stored in the hash table.
494 if (!DbgLoc.isUnknown()) {
495 Result.push_back(std::make_pair((unsigned)LLVMContext::MD_dbg,
496 DbgLoc.getAsMDNode(getContext())));
497 if (!hasMetadataHashEntry()) return;
500 assert(hasMetadataHashEntry() &&
501 getContext().pImpl->MetadataStore.count(this) &&
502 "Shouldn't have called this");
503 const LLVMContextImpl::MDMapTy &Info =
504 getContext().pImpl->MetadataStore.find(this)->second;
505 assert(!Info.empty() && "Shouldn't have called this");
507 Result.append(Info.begin(), Info.end());
509 // Sort the resulting array so it is stable.
510 if (Result.size() > 1)
511 array_pod_sort(Result.begin(), Result.end());
515 getAllMetadataOtherThanDebugLocImpl(SmallVectorImpl<std::pair<unsigned,
516 MDNode*> > &Result) const {
518 assert(hasMetadataHashEntry() &&
519 getContext().pImpl->MetadataStore.count(this) &&
520 "Shouldn't have called this");
521 const LLVMContextImpl::MDMapTy &Info =
522 getContext().pImpl->MetadataStore.find(this)->second;
523 assert(!Info.empty() && "Shouldn't have called this");
525 Result.append(Info.begin(), Info.end());
527 // Sort the resulting array so it is stable.
528 if (Result.size() > 1)
529 array_pod_sort(Result.begin(), Result.end());
533 /// clearMetadataHashEntries - Clear all hashtable-based metadata from
534 /// this instruction.
535 void Instruction::clearMetadataHashEntries() {
536 assert(hasMetadataHashEntry() && "Caller should check");
537 getContext().pImpl->MetadataStore.erase(this);
538 setHasMetadataHashEntry(false);