Changed |= runOnFunction(F);
if (Changed) {
- // stripDereferenceabilityInfo asserts that shouldRewriteStatepointsIn
+ // stripNonValidAttributes asserts that shouldRewriteStatepointsIn
// returns true for at least one function in the module. Since at least
// one function changed, we know that the precondition is satisfied.
- stripDereferenceabilityInfo(M);
+ stripNonValidAttributes(M);
}
return Changed;
/// dereferenceability that are no longer valid/correct after
/// RewriteStatepointsForGC has run. This is because semantically, after
/// RewriteStatepointsForGC runs, all calls to gc.statepoint "free" the entire
- /// heap. stripDereferenceabilityInfo (conservatively) restores correctness
+ /// heap. stripNonValidAttributes (conservatively) restores correctness
/// by erasing all attributes in the module that externally imply
/// dereferenceability.
- ///
- void stripDereferenceabilityInfo(Module &M);
+ /// Similar reasoning also applies to the noalias attributes. gc.statepoint
+ /// can touch the entire heap including noalias objects.
+ void stripNonValidAttributes(Module &M);
- // Helpers for stripDereferenceabilityInfo
- void stripDereferenceabilityInfoFromBody(Function &F);
- void stripDereferenceabilityInfoFromPrototype(Function &F);
+ // Helpers for stripNonValidAttributes
+ void stripNonValidAttributesFromBody(Function &F);
+ void stripNonValidAttributesFromPrototype(Function &F);
};
} // namespace
if (ArrayType *AT = dyn_cast<ArrayType>(Ty))
return containsGCPtrType(AT->getElementType());
if (StructType *ST = dyn_cast<StructType>(Ty))
- return std::any_of(
- ST->subtypes().begin(), ST->subtypes().end(),
- [](Type *SubType) { return containsGCPtrType(SubType); });
+ return std::any_of(ST->subtypes().begin(), ST->subtypes().end(),
+ containsGCPtrType);
return false;
}
// Generate the gc.relocate call and save the result
Value *BaseIdx =
Builder.getInt32(LiveStart + FindIndex(LiveVariables, BasePtrs[i]));
- Value *LiveIdx =
- Builder.getInt32(LiveStart + FindIndex(LiveVariables, LiveVariables[i]));
+ Value *LiveIdx = Builder.getInt32(LiveStart + i);
// only specify a debug name if we can give a useful one
CallInst *Reloc = Builder.CreateCall(
// Handles both return values and arguments for Functions and CallSites.
template <typename AttrHolder>
-static void RemoveDerefAttrAtIndex(LLVMContext &Ctx, AttrHolder &AH,
- unsigned Index) {
+static void RemoveNonValidAttrAtIndex(LLVMContext &Ctx, AttrHolder &AH,
+ unsigned Index) {
AttrBuilder R;
if (AH.getDereferenceableBytes(Index))
R.addAttribute(Attribute::get(Ctx, Attribute::Dereferenceable,
if (AH.getDereferenceableOrNullBytes(Index))
R.addAttribute(Attribute::get(Ctx, Attribute::DereferenceableOrNull,
AH.getDereferenceableOrNullBytes(Index)));
+ if (AH.doesNotAlias(Index))
+ R.addAttribute(Attribute::NoAlias);
if (!R.empty())
AH.setAttributes(AH.getAttributes().removeAttributes(
}
void
-RewriteStatepointsForGC::stripDereferenceabilityInfoFromPrototype(Function &F) {
+RewriteStatepointsForGC::stripNonValidAttributesFromPrototype(Function &F) {
LLVMContext &Ctx = F.getContext();
for (Argument &A : F.args())
if (isa<PointerType>(A.getType()))
- RemoveDerefAttrAtIndex(Ctx, F, A.getArgNo() + 1);
+ RemoveNonValidAttrAtIndex(Ctx, F, A.getArgNo() + 1);
if (isa<PointerType>(F.getReturnType()))
- RemoveDerefAttrAtIndex(Ctx, F, AttributeSet::ReturnIndex);
+ RemoveNonValidAttrAtIndex(Ctx, F, AttributeSet::ReturnIndex);
}
-void RewriteStatepointsForGC::stripDereferenceabilityInfoFromBody(Function &F) {
+void RewriteStatepointsForGC::stripNonValidAttributesFromBody(Function &F) {
if (F.empty())
return;
if (CallSite CS = CallSite(&I)) {
for (int i = 0, e = CS.arg_size(); i != e; i++)
if (isa<PointerType>(CS.getArgument(i)->getType()))
- RemoveDerefAttrAtIndex(Ctx, CS, i + 1);
+ RemoveNonValidAttrAtIndex(Ctx, CS, i + 1);
if (isa<PointerType>(CS.getType()))
- RemoveDerefAttrAtIndex(Ctx, CS, AttributeSet::ReturnIndex);
+ RemoveNonValidAttrAtIndex(Ctx, CS, AttributeSet::ReturnIndex);
}
}
}
return false;
}
-void RewriteStatepointsForGC::stripDereferenceabilityInfo(Module &M) {
+void RewriteStatepointsForGC::stripNonValidAttributes(Module &M) {
#ifndef NDEBUG
assert(std::any_of(M.begin(), M.end(), shouldRewriteStatepointsIn) &&
"precondition!");
#endif
for (Function &F : M)
- stripDereferenceabilityInfoFromPrototype(F);
+ stripNonValidAttributesFromPrototype(F);
for (Function &F : M)
- stripDereferenceabilityInfoFromBody(F);
+ stripNonValidAttributesFromBody(F);
}
bool RewriteStatepointsForGC::runOnFunction(Function &F) {