cl::location(ClobberNonLive),
cl::Hidden);
+static cl::opt<bool> UseDeoptBundles("rs4gc-use-deopt-bundles", cl::Hidden,
+ cl::init(false));
+static cl::opt<bool>
+ AllowStatepointWithNoDeoptInfo("rs4gc-allow-statepoint-with-no-deopt-info",
+ cl::Hidden, cl::init(true));
+
namespace {
struct RewriteStatepointsForGC : public ModulePass {
static char ID; // Pass identification, replacement for typeid
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/// dereferenceability that are no longer valid/correct after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
};
}
+static ArrayRef<Use> GetDeoptBundleOperands(ImmutableCallSite CS) {
+ assert(UseDeoptBundles && "Should not be called otherwise!");
+
+ Optional<OperandBundleUse> DeoptBundle = CS.getOperandBundle("deopt");
+
+ if (!DeoptBundle.hasValue()) {
+ assert(AllowStatepointWithNoDeoptInfo &&
+ "Found non-leaf call without deopt info!");
+ return None;
+ }
+
+ return DeoptBundle.getValue().Inputs;
+}
+
/// Compute the live-in set for every basic block in the function
static void computeLiveInValues(DominatorTree &DT, Function &F,
GCPtrLivenessData &Data);
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(
}
}
+namespace {
+
+/// This struct is used to defer RAUWs and `eraseFromParent` s. Using this
+/// avoids having to worry about keeping around dangling pointers to Values.
+class DeferredReplacement {
+ AssertingVH<Instruction> Old;
+ AssertingVH<Instruction> New;
+
+public:
+ explicit DeferredReplacement(Instruction *Old, Instruction *New) :
+ Old(Old), New(New) {
+ assert(Old != New && "Not allowed!");
+ }
+
+ /// Does the task represented by this instance.
+ void doReplacement() {
+ Instruction *OldI = Old;
+ Instruction *NewI = New;
+
+ assert(OldI != NewI && "Disallowed at construction?!");
+
+ Old = nullptr;
+ New = nullptr;
+
+ if (NewI)
+ OldI->replaceAllUsesWith(NewI);
+ OldI->eraseFromParent();
+ }
+};
+}
+
static void
makeStatepointExplicitImpl(const CallSite CS, /* to replace */
const SmallVectorImpl<Value *> &BasePtrs,
const SmallVectorImpl<Value *> &LiveVariables,
- PartiallyConstructedSafepointRecord &Result) {
+ PartiallyConstructedSafepointRecord &Result,
+ std::vector<DeferredReplacement> &Replacements) {
assert(BasePtrs.size() == LiveVariables.size());
- assert(isStatepoint(CS) &&
+ assert((UseDeoptBundles || isStatepoint(CS)) &&
"This method expects to be rewriting a statepoint");
- // We're not changing the function signature of the statepoint since the gc
- // arguments go into the var args section.
- Function *GCStatepointDecl = CS.getCalledFunction();
-
// Then go ahead and use the builder do actually do the inserts. We insert
// immediately before the previous instruction under the assumption that all
// arguments will be available here. We can't insert afterwards since we may
Instruction *InsertBefore = CS.getInstruction();
IRBuilder<> Builder(InsertBefore);
- // Copy all of the arguments from the original statepoint - this includes the
- // target, call args, and deopt args
- SmallVector<llvm::Value *, 64> Args;
- Args.insert(Args.end(), CS.arg_begin(), CS.arg_end());
- // TODO: Clear the 'needs rewrite' flag
+ ArrayRef<Value *> GCArgs(LiveVariables);
+ uint64_t StatepointID = 0xABCDEF00;
+ uint32_t NumPatchBytes = 0;
+ uint32_t Flags = uint32_t(StatepointFlags::None);
- // Add all the pointers to be relocated (gc arguments) and capture the start
- // of the live variable list for use in the gc_relocates
- const int LiveStartIdx = Args.size();
- Args.insert(Args.end(), LiveVariables.begin(), LiveVariables.end());
+ ArrayRef<Use> CallArgs;
+ ArrayRef<Use> DeoptArgs;
+ ArrayRef<Use> TransitionArgs;
+
+ Value *CallTarget = nullptr;
+
+ if (UseDeoptBundles) {
+ CallArgs = {CS.arg_begin(), CS.arg_end()};
+ DeoptArgs = GetDeoptBundleOperands(CS);
+ // TODO: we don't fill in TransitionArgs or Flags in this branch, but we
+ // could have an operand bundle for that too.
+ AttributeSet OriginalAttrs = CS.getAttributes();
+
+ Attribute AttrID = OriginalAttrs.getAttribute(AttributeSet::FunctionIndex,
+ "statepoint-id");
+ if (AttrID.isStringAttribute())
+ AttrID.getValueAsString().getAsInteger(10, StatepointID);
+
+ Attribute AttrNumPatchBytes = OriginalAttrs.getAttribute(
+ AttributeSet::FunctionIndex, "statepoint-num-patch-bytes");
+ if (AttrNumPatchBytes.isStringAttribute())
+ AttrNumPatchBytes.getValueAsString().getAsInteger(10, NumPatchBytes);
+
+ CallTarget = CS.getCalledValue();
+ } else {
+ // This branch will be gone soon, and we will soon only support the
+ // UseDeoptBundles == true configuration.
+ Statepoint OldSP(CS);
+ StatepointID = OldSP.getID();
+ NumPatchBytes = OldSP.getNumPatchBytes();
+ Flags = OldSP.getFlags();
+
+ CallArgs = {OldSP.arg_begin(), OldSP.arg_end()};
+ DeoptArgs = {OldSP.vm_state_begin(), OldSP.vm_state_end()};
+ TransitionArgs = {OldSP.gc_transition_args_begin(),
+ OldSP.gc_transition_args_end()};
+ CallTarget = OldSP.getCalledValue();
+ }
// Create the statepoint given all the arguments
Instruction *Token = nullptr;
AttributeSet ReturnAttrs;
if (CS.isCall()) {
CallInst *ToReplace = cast<CallInst>(CS.getInstruction());
- CallInst *Call =
- Builder.CreateCall(GCStatepointDecl, Args, "safepoint_token");
+ CallInst *Call = Builder.CreateGCStatepointCall(
+ StatepointID, NumPatchBytes, CallTarget, Flags, CallArgs,
+ TransitionArgs, DeoptArgs, GCArgs, "safepoint_token");
+
Call->setTailCall(ToReplace->isTailCall());
Call->setCallingConv(ToReplace->getCallingConv());
// Insert the new invoke into the old block. We'll remove the old one in a
// moment at which point this will become the new terminator for the
// original block.
- InvokeInst *Invoke =
- InvokeInst::Create(GCStatepointDecl, ToReplace->getNormalDest(),
- ToReplace->getUnwindDest(), Args, "statepoint_token",
- ToReplace->getParent());
+ InvokeInst *Invoke = Builder.CreateGCStatepointInvoke(
+ StatepointID, NumPatchBytes, CallTarget, ToReplace->getNormalDest(),
+ ToReplace->getUnwindDest(), Flags, CallArgs, TransitionArgs, DeoptArgs,
+ GCArgs, "statepoint_token");
+
Invoke->setCallingConv(ToReplace->getCallingConv());
// Currently we will fail on parameter attributes and on certain
UnwindBlock->getUniquePredecessor() &&
"can't safely insert in this block!");
- Builder.SetInsertPoint(UnwindBlock->getFirstInsertionPt());
+ Builder.SetInsertPoint(&*UnwindBlock->getFirstInsertionPt());
Builder.SetCurrentDebugLocation(ToReplace->getDebugLoc());
// Extract second element from landingpad return value. We will attach
UnwindBlock->getLandingPadInst(), 1, "relocate_token"));
Result.UnwindToken = ExceptionalToken;
+ const unsigned LiveStartIdx = Statepoint(Token).gcArgsStartIdx();
CreateGCRelocates(LiveVariables, LiveStartIdx, BasePtrs, ExceptionalToken,
Builder);
NormalDest->getUniquePredecessor() &&
"can't safely insert in this block!");
- Builder.SetInsertPoint(NormalDest->getFirstInsertionPt());
+ Builder.SetInsertPoint(&*NormalDest->getFirstInsertionPt());
// gc relocates will be generated later as if it were regular call
// statepoint
}
assert(Token && "Should be set in one of the above branches!");
- // Take the name of the original value call if it had one.
- Token->takeName(CS.getInstruction());
+ if (UseDeoptBundles) {
+ Token->setName("statepoint_token");
+ if (!CS.getType()->isVoidTy() && !CS.getInstruction()->use_empty()) {
+ StringRef Name =
+ CS.getInstruction()->hasName() ? CS.getInstruction()->getName() : "";
+ CallInst *GCResult = Builder.CreateGCResult(Token, CS.getType(), Name);
+ GCResult->setAttributes(CS.getAttributes().getRetAttributes());
+
+ // We cannot RAUW or delete CS.getInstruction() because it could be in the
+ // live set of some other safepoint, in which case that safepoint's
+ // PartiallyConstructedSafepointRecord will hold a raw pointer to this
+ // llvm::Instruction. Instead, we defer the replacement and deletion to
+ // after the live sets have been made explicit in the IR, and we no longer
+ // have raw pointers to worry about.
+ Replacements.emplace_back(CS.getInstruction(), GCResult);
+ } else {
+ Replacements.emplace_back(CS.getInstruction(), nullptr);
+ }
+ } else {
+ assert(!CS.getInstruction()->hasNUsesOrMore(2) &&
+ "only valid use before rewrite is gc.result");
+ assert(!CS.getInstruction()->hasOneUse() ||
+ isGCResult(cast<Instruction>(*CS.getInstruction()->user_begin())));
-// The GCResult is already inserted, we just need to find it
-#ifndef NDEBUG
- Instruction *ToReplace = CS.getInstruction();
- assert(!ToReplace->hasNUsesOrMore(2) &&
- "only valid use before rewrite is gc.result");
- assert(!ToReplace->hasOneUse() ||
- isGCResult(cast<Instruction>(*ToReplace->user_begin())));
-#endif
+ // Take the name of the original statepoint token if there was one.
+ Token->takeName(CS.getInstruction());
- // Update the gc.result of the original statepoint (if any) to use the newly
- // inserted statepoint. This is safe to do here since the token can't be
- // considered a live reference.
- CS.getInstruction()->replaceAllUsesWith(Token);
+ // Update the gc.result of the original statepoint (if any) to use the newly
+ // inserted statepoint. This is safe to do here since the token can't be
+ // considered a live reference.
+ CS.getInstruction()->replaceAllUsesWith(Token);
+ CS.getInstruction()->eraseFromParent();
+ }
Result.StatepointToken = Token;
// Second, create a gc.relocate for every live variable
+ const unsigned LiveStartIdx = Statepoint(Token).gcArgsStartIdx();
CreateGCRelocates(LiveVariables, LiveStartIdx, BasePtrs, Token, Builder);
}
// values. That's the callers responsibility.
static void
makeStatepointExplicit(DominatorTree &DT, const CallSite &CS,
- PartiallyConstructedSafepointRecord &Result) {
- auto LiveSet = Result.LiveSet;
- auto PointerToBase = Result.PointerToBase;
+ PartiallyConstructedSafepointRecord &Result,
+ std::vector<DeferredReplacement> &Replacements) {
+ const auto &LiveSet = Result.LiveSet;
+ const auto &PointerToBase = Result.PointerToBase;
// Convert to vector for efficient cross referencing.
SmallVector<Value *, 64> BaseVec, LiveVec;
for (Value *L : LiveSet) {
LiveVec.push_back(L);
assert(PointerToBase.count(L));
- Value *Base = PointerToBase[L];
+ Value *Base = PointerToBase.find(L)->second;
BaseVec.push_back(Base);
}
assert(LiveVec.size() == BaseVec.size());
StabilizeOrder(BaseVec, LiveVec);
// Do the actual rewriting and delete the old statepoint
- makeStatepointExplicitImpl(CS, BaseVec, LiveVec, Result);
- CS.getInstruction()->eraseFromParent();
+ makeStatepointExplicitImpl(CS, BaseVec, LiveVec, Result, Replacements);
}
// Helper function for the relocationViaAlloca.
// Insert the clobbering stores. These may get intermixed with the
// gc.results and gc.relocates, but that's fine.
if (auto II = dyn_cast<InvokeInst>(Statepoint)) {
- InsertClobbersAt(II->getNormalDest()->getFirstInsertionPt());
- InsertClobbersAt(II->getUnwindDest()->getFirstInsertionPt());
+ InsertClobbersAt(&*II->getNormalDest()->getFirstInsertionPt());
+ InsertClobbersAt(&*II->getUnwindDest()->getFirstInsertionPt());
} else {
InsertClobbersAt(cast<Instruction>(Statepoint)->getNextNode());
}
"__tmp_use", FunctionType::get(Type::getVoidTy(M->getContext()), true)));
if (CS.isCall()) {
// For call safepoints insert dummy calls right after safepoint
- BasicBlock::iterator Next(CS.getInstruction());
- Next++;
- Holders.push_back(CallInst::Create(Func, Values, "", Next));
+ Holders.push_back(CallInst::Create(Func, Values, "",
+ &*++CS.getInstruction()->getIterator()));
return;
}
// For invoke safepooints insert dummy calls both in normal and
// exceptional destination blocks
auto *II = cast<InvokeInst>(CS.getInstruction());
Holders.push_back(CallInst::Create(
- Func, Values, "", II->getNormalDest()->getFirstInsertionPt()));
+ Func, Values, "", &*II->getNormalDest()->getFirstInsertionPt()));
Holders.push_back(CallInst::Create(
- Func, Values, "", II->getUnwindDest()->getFirstInsertionPt()));
+ Func, Values, "", &*II->getUnwindDest()->getFirstInsertionPt()));
}
static void findLiveReferences(
InvokeInst *Invoke = cast<InvokeInst>(CS.getInstruction());
Instruction *NormalInsertBefore =
- Invoke->getNormalDest()->getFirstInsertionPt();
+ &*Invoke->getNormalDest()->getFirstInsertionPt();
Instruction *UnwindInsertBefore =
- Invoke->getUnwindDest()->getFirstInsertionPt();
+ &*Invoke->getUnwindDest()->getFirstInsertionPt();
Instruction *NormalRematerializedValue =
rematerializeChain(NormalInsertBefore);
for (CallSite CS : ToUpdate) {
assert(CS.getInstruction()->getParent()->getParent() == &F);
- assert(isStatepoint(CS) && "expected to already be a deopt statepoint");
+ assert((UseDeoptBundles || isStatepoint(CS)) &&
+ "expected to already be a deopt statepoint");
}
#endif
// the deopt argument list are considered live through the safepoint (and
// thus makes sure they get relocated.)
for (CallSite CS : ToUpdate) {
- Statepoint StatepointCS(CS);
-
SmallVector<Value *, 64> DeoptValues;
- for (Use &U : StatepointCS.vm_state_args()) {
- Value *Arg = cast<Value>(&U);
+
+ iterator_range<const Use *> DeoptStateRange =
+ UseDeoptBundles
+ ? iterator_range<const Use *>(GetDeoptBundleOperands(CS))
+ : iterator_range<const Use *>(Statepoint(CS).vm_state_args());
+
+ for (Value *Arg : DeoptStateRange) {
assert(!isUnhandledGCPointerType(Arg->getType()) &&
"support for FCA unimplemented");
if (isHandledGCPointerType(Arg->getType()))
DeoptValues.push_back(Arg);
}
+
insertUseHolderAfter(CS, DeoptValues, Holders);
}
for (size_t i = 0; i < Records.size(); i++)
rematerializeLiveValues(ToUpdate[i], Records[i], TTI);
+ // We need this to safely RAUW and delete call or invoke return values that
+ // may themselves be live over a statepoint. For details, please see usage in
+ // makeStatepointExplicitImpl.
+ std::vector<DeferredReplacement> Replacements;
+
// Now run through and replace the existing statepoints with new ones with
// the live variables listed. We do not yet update uses of the values being
// relocated. We have references to live variables that need to
// previous statepoint can not be a live variable, thus we can and remove
// the old statepoint calls as we go.)
for (size_t i = 0; i < Records.size(); i++)
- makeStatepointExplicit(DT, ToUpdate[i], Records[i]);
+ makeStatepointExplicit(DT, ToUpdate[i], Records[i], Replacements);
ToUpdate.clear(); // prevent accident use of invalid CallSites
+ for (auto &PR : Replacements)
+ PR.doReplacement();
+
+ Replacements.clear();
+
+ for (auto &Info : Records) {
+ // These live sets may contain state Value pointers, since we replaced calls
+ // with operand bundles with calls wrapped in gc.statepoint, and some of
+ // those calls may have been def'ing live gc pointers. Clear these out to
+ // avoid accidentally using them.
+ //
+ // TODO: We should create a separate data structure that does not contain
+ // these live sets, and migrate to using that data structure from this point
+ // onward.
+ Info.LiveSet.clear();
+ Info.PointerToBase.clear();
+ }
+
// Do all the fixups of the original live variables to their relocated selves
SmallVector<Value *, 128> Live;
for (size_t i = 0; i < Records.size(); i++) {
PartiallyConstructedSafepointRecord &Info = Records[i];
+
// We can't simply save the live set from the original insertion. One of
// the live values might be the result of a call which needs a safepoint.
// That Value* no longer exists and we need to use the new gc_result.
// 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) {
DominatorTree &DT = getAnalysis<DominatorTreeWrapperPass>(F).getDomTree();
+ auto NeedsRewrite = [](Instruction &I) {
+ if (UseDeoptBundles) {
+ if (ImmutableCallSite CS = ImmutableCallSite(&I))
+ return !callsGCLeafFunction(CS);
+ return false;
+ }
+
+ return isStatepoint(I);
+ };
+
// Gather all the statepoints which need rewritten. Be careful to only
// consider those in reachable code since we need to ask dominance queries
// when rewriting. We'll delete the unreachable ones in a moment.
bool HasUnreachableStatepoint = false;
for (Instruction &I : instructions(F)) {
// TODO: only the ones with the flag set!
- if (isStatepoint(I)) {
+ if (NeedsRewrite(I)) {
if (DT.isReachableFromEntry(I.getParent()))
ParsePointNeeded.push_back(CallSite(&I));
else
// call result is not live (normal), nor are it's arguments
// (unless they're used again later). This adjustment is
// specifically what we need to relocate
- BasicBlock::reverse_iterator rend(Inst);
+ BasicBlock::reverse_iterator rend(Inst->getIterator());
computeLiveInValues(BB->rbegin(), rend, LiveOut);
LiveOut.erase(Inst);
Out.insert(LiveOut.begin(), LiveOut.end());
projects / oota-llvm.git / blobdiff