// Replace value from this node's operand list.
void MDNode::replaceOperand(MDNodeOperand *Op, Value *To) {
Value *From = *Op;
// If is possible that someone did GV->RAUW(inst), replacing a global variable
// with an instruction or some other function-local object. If this is a
// non-function-local MDNode, it can't point to a function-local object.
// Handle this case by implicitly dropping the MDNode reference to null.
if (!isFunctionLocal() && To && isFunctionLocalValue(To))
To = 0;
if (From == To)
return;
// Update the operand.
Op->set(To);
// If this node is already not being uniqued (because one of the operands
// already went to null), then there is nothing else to do here.
if (isNotUniqued()) return;
LLVMContextImpl *pImpl = getType()->getContext().pImpl;
// Remove "this" from the context map. FoldingSet doesn't have to reprofile
// this node to remove it, so we don't care what state the operands are in.
pImpl->MDNodeSet.RemoveNode(this);
// If we are dropping an argument to null, we choose to not unique the MDNode
// anymore. This commonly occurs during destruction, and uniquing these
// brings little reuse.
if (To == 0) {
setIsNotUniqued();
return;
}
// Now that the node is out of the folding set, get ready to reinsert it.
// First, check to see if another node with the same operands already exists
// in the set. If it doesn't exist, this returns the position to insert it.
FoldingSetNodeID ID;
Profile(ID);
void *InsertPoint;
MDNode *N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
if (N) {
N->replaceAllUsesWith(this);
N->destroy();
N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
assert(N == 0 && "shouldn't be in the map now!"); (void)N;
}
// InsertPoint will have been set by the FindNodeOrInsertPos call.
pImpl->MDNodeSet.InsertNode(this, InsertPoint);
}
// Replace value from this node's operand list.
void MDNode::replaceOperand(MDNodeOperand *Op, Value *To) {
Value *From = *Op;
// If is possible that someone did GV->RAUW(inst), replacing a global variable
// with an instruction or some other function-local object. If this is a
// non-function-local MDNode, it can't point to a function-local object.
// Handle this case by implicitly dropping the MDNode reference to null.
// Likewise if the MDNode is function-local but for a different function.
if (To && isFunctionLocalValue(To)) {
if (!isFunctionLocal())
To = 0;
else {
const Function *F = getFunction();
const Function *FV = getFunctionForValue(To);
// Metadata can be function-local without having an associated function.
// So only consider functions to have changed if non-null.
if (F && FV && F != FV)
To = 0;
}
}
if (From == To)
return;
// Update the operand.
Op->set(To);
// If this node is already not being uniqued (because one of the operands
// already went to null), then there is nothing else to do here.
if (isNotUniqued()) return;
LLVMContextImpl *pImpl = getType()->getContext().pImpl;
// Remove "this" from the context map. FoldingSet doesn't have to reprofile
// this node to remove it, so we don't care what state the operands are in.
pImpl->MDNodeSet.RemoveNode(this);
// If we are dropping an argument to null, we choose to not unique the MDNode
// anymore. This commonly occurs during destruction, and uniquing these
// brings little reuse. Also, this means we don't need to include
// isFunctionLocal bits in FoldingSetNodeIDs for MDNodes.
if (To == 0) {
setIsNotUniqued();
return;
}
// Now that the node is out of the folding set, get ready to reinsert it.
// First, check to see if another node with the same operands already exists
// in the set. If it doesn't exist, this returns the position to insert it.
FoldingSetNodeID ID;
Profile(ID);
void *InsertPoint;
MDNode *N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
if (N) {
N->replaceAllUsesWith(this);
N->destroy();
N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
assert(N == 0 && "shouldn't be in the map now!"); (void)N;
}
// InsertPoint will have been set by the FindNodeOrInsertPos call.
pImpl->MDNodeSet.InsertNode(this, InsertPoint);
// If this MDValue was previously function-local but no longer is, clear
// its function-local flag.
if (isFunctionLocal() && !isFunctionLocalValue(To)) {
bool isStillFunctionLocal = false;
for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
Value *V = getOperand(i);
if (!V) continue;
if (isFunctionLocalValue(V)) {
isStillFunctionLocal = true;
break;
}
}
if (!isStillFunctionLocal)
setValueSubclassData(getSubclassDataFromValue() & ~FunctionLocalBit);
}
}
