const MDNode *Node;
public:
- TBAANode() : Node(0) {}
+ TBAANode() : Node(nullptr) {}
explicit TBAANode(const MDNode *N) : Node(N) {}
/// getNode - Get the MDNode for this TBAANode.
const MDNode *Node;
public:
- TBAAStructTagNode() : Node(0) {}
explicit TBAAStructTagNode(const MDNode *N) : Node(N) {}
/// Get the MDNode for this TBAAStructTagNode.
const MDNode *Node;
public:
- TBAAStructTypeNode() : Node(0) {}
+ TBAAStructTypeNode() : Node(nullptr) {}
explicit TBAAStructTypeNode(const MDNode *N) : Node(N) {}
/// Get the MDNode for this TBAAStructTypeNode.
if (Node->getNumOperands() < 2)
return TBAAStructTypeNode();
- // Special handling for a scalar type node.
+ // Fast path for a scalar type node and a struct type node with a single
+ // field.
if (Node->getNumOperands() <= 3) {
+ uint64_t Cur = Node->getNumOperands() == 2 ? 0 :
+ cast<ConstantInt>(Node->getOperand(2))->getZExtValue();
+ Offset -= Cur;
MDNode *P = dyn_cast_or_null<MDNode>(Node->getOperand(1));
if (!P)
return TBAAStructTypeNode();
initializeTypeBasedAliasAnalysisPass(*PassRegistry::getPassRegistry());
}
- virtual void initializePass() {
+ void initializePass() override {
InitializeAliasAnalysis(this);
}
/// an analysis interface through multiple inheritance. If needed, it
/// should override this to adjust the this pointer as needed for the
/// specified pass info.
- virtual void *getAdjustedAnalysisPointer(const void *PI) {
+ void *getAdjustedAnalysisPointer(const void *PI) override {
if (PI == &AliasAnalysis::ID)
return (AliasAnalysis*)this;
return this;
bool PathAliases(const MDNode *A, const MDNode *B) const;
private:
- virtual void getAnalysisUsage(AnalysisUsage &AU) const;
- virtual AliasResult alias(const Location &LocA, const Location &LocB);
- virtual bool pointsToConstantMemory(const Location &Loc, bool OrLocal);
- virtual ModRefBehavior getModRefBehavior(ImmutableCallSite CS);
- virtual ModRefBehavior getModRefBehavior(const Function *F);
- virtual ModRefResult getModRefInfo(ImmutableCallSite CS,
- const Location &Loc);
- virtual ModRefResult getModRefInfo(ImmutableCallSite CS1,
- ImmutableCallSite CS2);
+ void getAnalysisUsage(AnalysisUsage &AU) const override;
+ AliasResult alias(const Location &LocA, const Location &LocB) override;
+ bool pointsToConstantMemory(const Location &Loc, bool OrLocal) override;
+ ModRefBehavior getModRefBehavior(ImmutableCallSite CS) override;
+ ModRefBehavior getModRefBehavior(const Function *F) override;
+ ModRefResult getModRefInfo(ImmutableCallSite CS,
+ const Location &Loc) override;
+ ModRefResult getModRefInfo(ImmutableCallSite CS1,
+ ImmutableCallSite CS2) override;
};
} // End of anonymous namespace
/// it as struct-path aware TBAA format, otherwise, we treat it as scalar TBAA
/// format.
static bool isStructPathTBAA(const MDNode *MD) {
- return isa<MDNode>(MD->getOperand(0));
+ // Anonymous TBAA root starts with a MDNode and dragonegg uses it as
+ // a TBAA tag.
+ return isa<MDNode>(MD->getOperand(0)) && MD->getNumOperands() >= 3;
}
/// Aliases - Test whether the type represented by A may alias the
bool
TypeBasedAliasAnalysis::Aliases(const MDNode *A,
const MDNode *B) const {
- if (isStructPathTBAA(A))
+ // Make sure that both MDNodes are struct-path aware.
+ if (isStructPathTBAA(A) && isStructPathTBAA(B))
return PathAliases(A, B);
// Keep track of the root node for A and B.
bool
TypeBasedAliasAnalysis::PathAliases(const MDNode *A,
const MDNode *B) const {
+ // Verify that both input nodes are struct-path aware.
+ assert(isStructPathTBAA(A) && "MDNode A is not struct-path aware.");
+ assert(isStructPathTBAA(B) && "MDNode B is not struct-path aware.");
+
// Keep track of the root node for A and B.
TBAAStructTypeNode RootA, RootB;
TBAAStructTagNode TagA(A), TagB(B);
MDNode *MDNode::getMostGenericTBAA(MDNode *A, MDNode *B) {
if (!A || !B)
- return NULL;
+ return nullptr;
if (A == B)
return A;
// For struct-path aware TBAA, we use the access type of the tag.
- bool StructPath = isStructPathTBAA(A);
+ bool StructPath = isStructPathTBAA(A) && isStructPathTBAA(B);
if (StructPath) {
A = cast_or_null<MDNode>(A->getOperand(1));
- if (!A) return 0;
+ if (!A) return nullptr;
B = cast_or_null<MDNode>(B->getOperand(1));
- if (!B) return 0;
+ if (!B) return nullptr;
}
SmallVector<MDNode *, 4> PathA;
MDNode *T = A;
while (T) {
PathA.push_back(T);
- T = T->getNumOperands() >= 2 ? cast_or_null<MDNode>(T->getOperand(1)) : 0;
+ T = T->getNumOperands() >= 2 ? cast_or_null<MDNode>(T->getOperand(1))
+ : nullptr;
}
SmallVector<MDNode *, 4> PathB;
T = B;
while (T) {
PathB.push_back(T);
- T = T->getNumOperands() >= 2 ? cast_or_null<MDNode>(T->getOperand(1)) : 0;
+ T = T->getNumOperands() >= 2 ? cast_or_null<MDNode>(T->getOperand(1))
+ : nullptr;
}
int IA = PathA.size() - 1;
int IB = PathB.size() - 1;
- MDNode *Ret = 0;
+ MDNode *Ret = nullptr;
while (IA >= 0 && IB >=0) {
if (PathA[IA] == PathB[IB])
Ret = PathA[IA];
return Ret;
if (!Ret)
- return 0;
+ return nullptr;
// We need to convert from a type node to a tag node.
Type *Int64 = IntegerType::get(A->getContext(), 64);
Value *Ops[3] = { Ret, Ret, ConstantInt::get(Int64, 0) };