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
This commit is contained in:
Victor Hernandez 2010-01-26 02:36:35 +00:00
parent 4cf292a86d
commit e685f230b6
2 changed files with 45 additions and 30 deletions

View File

@ -112,7 +112,7 @@ protected:
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 @@ public:
// 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;

View File

@ -186,43 +186,50 @@ void MDNode::destroy() {
}
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 @@ MDNode *MDNode::get(LLVMContext &Context, Value*const* Vals, unsigned NumVals) {
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);