Add MDNode::getIfExists(), an efficient way to determine if a value is used by metadata (since metadata does not appear in a value's use list)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94492 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/llvm/Metadata.h b/include/llvm/Metadata.h
index f1e7a22..4e459bf 100644
--- a/include/llvm/Metadata.h
+++ b/include/llvm/Metadata.h
@@ -112,7 +112,7 @@
bool isFunctionLocal);
static MDNode *getMDNode(LLVMContext &C, Value *const *Vals, unsigned NumVals,
- FunctionLocalness FL);
+ FunctionLocalness FL, bool Insert = true);
public:
// Constructors and destructors.
static MDNode *get(LLVMContext &Context, Value *const *Vals,
@@ -121,6 +121,9 @@
// from isFunctionLocal argument, not by analyzing Vals.
static MDNode *getWhenValsUnresolved(LLVMContext &Context, Value *const *Vals,
unsigned NumVals, bool isFunctionLocal);
+
+ static MDNode *getIfExists(LLVMContext &Context, Value *const *Vals,
+ unsigned NumVals);
/// getOperand - Return specified operand.
Value *getOperand(unsigned i) const;
diff --git a/lib/VMCore/Metadata.cpp b/lib/VMCore/Metadata.cpp
index ee8e713..07a5f3c 100644
--- a/lib/VMCore/Metadata.cpp
+++ b/lib/VMCore/Metadata.cpp
@@ -186,43 +186,50 @@
}
MDNode *MDNode::getMDNode(LLVMContext &Context, Value *const *Vals,
- unsigned NumVals, FunctionLocalness FL) {
+ unsigned NumVals, FunctionLocalness FL,
+ bool Insert) {
LLVMContextImpl *pImpl = Context.pImpl;
FoldingSetNodeID ID;
for (unsigned i = 0; i != NumVals; ++i)
ID.AddPointer(Vals[i]);
void *InsertPoint;
- MDNode *N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
- if (!N) {
- bool isFunctionLocal = false;
- switch (FL) {
- case FL_Unknown:
- for (unsigned i = 0; i != NumVals; ++i) {
- Value *V = Vals[i];
- if (!V) continue;
- if (isa<Instruction>(V) || isa<Argument>(V) || isa<BasicBlock>(V) ||
- (isa<MDNode>(V) && cast<MDNode>(V)->isFunctionLocal())) {
- isFunctionLocal = true;
- break;
- }
+ MDNode *N = NULL;
+
+ if ((N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint)))
+ return N;
+
+ if (!Insert)
+ return NULL;
+
+ bool isFunctionLocal = false;
+ switch (FL) {
+ case FL_Unknown:
+ for (unsigned i = 0; i != NumVals; ++i) {
+ Value *V = Vals[i];
+ if (!V) continue;
+ if (isa<Instruction>(V) || isa<Argument>(V) || isa<BasicBlock>(V) ||
+ (isa<MDNode>(V) && cast<MDNode>(V)->isFunctionLocal())) {
+ isFunctionLocal = true;
+ break;
}
- break;
- case FL_No:
- isFunctionLocal = false;
- break;
- case FL_Yes:
- isFunctionLocal = true;
- break;
}
-
- // Coallocate space for the node and Operands together, then placement new.
- void *Ptr = malloc(sizeof(MDNode)+NumVals*sizeof(MDNodeOperand));
- N = new (Ptr) MDNode(Context, Vals, NumVals, isFunctionLocal);
-
- // InsertPoint will have been set by the FindNodeOrInsertPos call.
- pImpl->MDNodeSet.InsertNode(N, InsertPoint);
+ break;
+ case FL_No:
+ isFunctionLocal = false;
+ break;
+ case FL_Yes:
+ isFunctionLocal = true;
+ break;
}
+
+ // Coallocate space for the node and Operands together, then placement new.
+ void *Ptr = malloc(sizeof(MDNode)+NumVals*sizeof(MDNodeOperand));
+ N = new (Ptr) MDNode(Context, Vals, NumVals, isFunctionLocal);
+
+ // InsertPoint will have been set by the FindNodeOrInsertPos call.
+ pImpl->MDNodeSet.InsertNode(N, InsertPoint);
+
return N;
}
@@ -230,11 +237,16 @@
return getMDNode(Context, Vals, NumVals, FL_Unknown);
}
-MDNode *MDNode::getWhenValsUnresolved(LLVMContext &Context, Value*const* Vals,
+MDNode *MDNode::getWhenValsUnresolved(LLVMContext &Context, Value *const *Vals,
unsigned NumVals, bool isFunctionLocal) {
return getMDNode(Context, Vals, NumVals, isFunctionLocal ? FL_Yes : FL_No);
}
+MDNode *MDNode::getIfExists(LLVMContext &Context, Value *const *Vals,
+ unsigned NumVals) {
+ return getMDNode(Context, Vals, NumVals, FL_Unknown, false);
+}
+
/// getOperand - Return specified operand.
Value *MDNode::getOperand(unsigned i) const {
return *getOperandPtr(const_cast<MDNode*>(this), i);