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/// dereferenceability that are no longer valid/correct after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;
}
}
}
-// When inserting gc.relocate calls, we need to ensure there are no uses
-// of the original value between the gc.statepoint and the gc.relocate call.
-// One case which can arise is a phi node starting one of the successor blocks.
-// We also need to be able to insert the gc.relocates only on the path which
-// goes through the statepoint. We might need to split an edge to make this
-// possible.
+// When inserting gc.relocate and gc.result calls, we need to ensure there are
+// no uses of the original value / return value between the gc.statepoint and
+// the gc.relocate / gc.result call. One case which can arise is a phi node
+// starting one of the successor blocks. We also need to be able to insert the
+// gc.relocates only on the path which goes through the statepoint. We might
+// need to split an edge to make this possible.
static BasicBlock *
normalizeForInvokeSafepoint(BasicBlock *BB, BasicBlock *InvokeParent,
DominatorTree &DT) {
BasicBlock *Ret = BB;
- if (!BB->getUniquePredecessor()) {
+ if (!BB->getUniquePredecessor())
Ret = SplitBlockPredecessors(BB, InvokeParent, "", &DT);
- }
- // Now that 'ret' has unique predecessor we can safely remove all phi nodes
+ // Now that 'Ret' has unique predecessor we can safely remove all phi nodes
// from it
FoldSingleEntryPHINodes(Ret);
- assert(!isa<PHINode>(Ret->begin()));
+ assert(!isa<PHINode>(Ret->begin()) &&
+ "All PHI nodes should have been removed!");
- // At this point, we can safely insert a gc.relocate as the first instruction
- // in Ret if needed.
+ // At this point, we can safely insert a gc.relocate or gc.result as the first
+ // instruction in Ret if needed.
return Ret;
}
-static int find_index(ArrayRef<Value *> livevec, Value *val) {
- auto itr = std::find(livevec.begin(), livevec.end(), val);
- assert(livevec.end() != itr);
- size_t index = std::distance(livevec.begin(), itr);
- assert(index < livevec.size());
- return index;
-}
-
// Create new attribute set containing only attributes which can be transferred
// from original call to the safepoint.
static AttributeSet legalizeCallAttributes(AttributeSet AS) {
- AttributeSet ret;
+ AttributeSet Ret;
for (unsigned Slot = 0; Slot < AS.getNumSlots(); Slot++) {
- unsigned index = AS.getSlotIndex(Slot);
+ unsigned Index = AS.getSlotIndex(Slot);
- if (index == AttributeSet::ReturnIndex ||
- index == AttributeSet::FunctionIndex) {
+ if (Index == AttributeSet::ReturnIndex ||
+ Index == AttributeSet::FunctionIndex) {
- for (auto it = AS.begin(Slot), it_end = AS.end(Slot); it != it_end;
- ++it) {
- Attribute attr = *it;
+ for (Attribute Attr : make_range(AS.begin(Slot), AS.end(Slot))) {
// Do not allow certain attributes - just skip them
// Safepoint can not be read only or read none.
- if (attr.hasAttribute(Attribute::ReadNone) ||
- attr.hasAttribute(Attribute::ReadOnly))
+ if (Attr.hasAttribute(Attribute::ReadNone) ||
+ Attr.hasAttribute(Attribute::ReadOnly))
+ continue;
+
+ // These attributes control the generation of the gc.statepoint call /
+ // invoke itself; and once the gc.statepoint is in place, they're of no
+ // use.
+ if (Attr.hasAttribute("statepoint-num-patch-bytes") ||
+ Attr.hasAttribute("statepoint-id"))
continue;
- ret = ret.addAttributes(
- AS.getContext(), index,
- AttributeSet::get(AS.getContext(), index, AttrBuilder(attr)));
+ Ret = Ret.addAttributes(
+ AS.getContext(), Index,
+ AttributeSet::get(AS.getContext(), Index, AttrBuilder(Attr)));
}
}
// Just skip parameter attributes for now
}
- return ret;
+ return Ret;
}
/// Helper function to place all gc relocates necessary for the given
IRBuilder<> Builder) {
if (LiveVariables.empty())
return;
-
+
+ auto FindIndex = [](ArrayRef<Value *> LiveVec, Value *Val) {
+ auto ValIt = std::find(LiveVec.begin(), LiveVec.end(), Val);
+ assert(ValIt != LiveVec.end() && "Val not found in LiveVec!");
+ size_t Index = std::distance(LiveVec.begin(), ValIt);
+ assert(Index < LiveVec.size() && "Bug in std::find?");
+ return Index;
+ };
+
// All gc_relocate are set to i8 addrspace(1)* type. We originally generated
// unique declarations for each pointer type, but this proved problematic
// because the intrinsic mangling code is incomplete and fragile. Since
for (unsigned i = 0; i < LiveVariables.size(); i++) {
// Generate the gc.relocate call and save the result
Value *BaseIdx =
- Builder.getInt32(LiveStart + find_index(LiveVariables, BasePtrs[i]));
- Value *LiveIdx =
- Builder.getInt32(LiveStart + find_index(LiveVariables, LiveVariables[i]));
+ Builder.getInt32(LiveStart + FindIndex(LiveVariables, BasePtrs[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) {
projects / oota-llvm.git / blobdiff