///
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "objc-arc-opts"
#include "ObjCARC.h"
+#include "ARCRuntimeEntryPoints.h"
#include "DependencyAnalysis.h"
#include "ObjCARCAliasAnalysis.h"
#include "ProvenanceAnalysis.h"
+#include "BlotMapVector.h"
+#include "PtrState.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/Statistic.h"
+#include "llvm/IR/CFG.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/LLVMContext.h"
-#include "llvm/Support/CFG.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
using namespace llvm::objcarc;
-/// \defgroup MiscUtils Miscellaneous utilities that are not ARC specific.
-/// @{
-
-namespace {
- /// \brief An associative container with fast insertion-order (deterministic)
- /// iteration over its elements. Plus the special blot operation.
- template<class KeyT, class ValueT>
- class MapVector {
- /// Map keys to indices in Vector.
- typedef DenseMap<KeyT, size_t> MapTy;
- MapTy Map;
-
- typedef std::vector<std::pair<KeyT, ValueT> > VectorTy;
- /// Keys and values.
- VectorTy Vector;
-
- public:
- typedef typename VectorTy::iterator iterator;
- typedef typename VectorTy::const_iterator const_iterator;
- iterator begin() { return Vector.begin(); }
- iterator end() { return Vector.end(); }
- const_iterator begin() const { return Vector.begin(); }
- const_iterator end() const { return Vector.end(); }
-
-#ifdef XDEBUG
- ~MapVector() {
- assert(Vector.size() >= Map.size()); // May differ due to blotting.
- for (typename MapTy::const_iterator I = Map.begin(), E = Map.end();
- I != E; ++I) {
- assert(I->second < Vector.size());
- assert(Vector[I->second].first == I->first);
- }
- for (typename VectorTy::const_iterator I = Vector.begin(),
- E = Vector.end(); I != E; ++I)
- assert(!I->first ||
- (Map.count(I->first) &&
- Map[I->first] == size_t(I - Vector.begin())));
- }
-#endif
-
- ValueT &operator[](const KeyT &Arg) {
- std::pair<typename MapTy::iterator, bool> Pair =
- Map.insert(std::make_pair(Arg, size_t(0)));
- if (Pair.second) {
- size_t Num = Vector.size();
- Pair.first->second = Num;
- Vector.push_back(std::make_pair(Arg, ValueT()));
- return Vector[Num].second;
- }
- return Vector[Pair.first->second].second;
- }
-
- std::pair<iterator, bool>
- insert(const std::pair<KeyT, ValueT> &InsertPair) {
- std::pair<typename MapTy::iterator, bool> Pair =
- Map.insert(std::make_pair(InsertPair.first, size_t(0)));
- if (Pair.second) {
- size_t Num = Vector.size();
- Pair.first->second = Num;
- Vector.push_back(InsertPair);
- return std::make_pair(Vector.begin() + Num, true);
- }
- return std::make_pair(Vector.begin() + Pair.first->second, false);
- }
-
- iterator find(const KeyT &Key) {
- typename MapTy::iterator It = Map.find(Key);
- if (It == Map.end()) return Vector.end();
- return Vector.begin() + It->second;
- }
-
- const_iterator find(const KeyT &Key) const {
- typename MapTy::const_iterator It = Map.find(Key);
- if (It == Map.end()) return Vector.end();
- return Vector.begin() + It->second;
- }
-
- /// This is similar to erase, but instead of removing the element from the
- /// vector, it just zeros out the key in the vector. This leaves iterators
- /// intact, but clients must be prepared for zeroed-out keys when iterating.
- void blot(const KeyT &Key) {
- typename MapTy::iterator It = Map.find(Key);
- if (It == Map.end()) return;
- Vector[It->second].first = KeyT();
- Map.erase(It);
- }
-
- void clear() {
- Map.clear();
- Vector.clear();
- }
- };
-}
+#define DEBUG_TYPE "objc-arc-opts"
-/// @}
-///
/// \defgroup ARCUtilities Utility declarations/definitions specific to ARC.
/// @{
-/// \brief This is similar to StripPointerCastsAndObjCCalls but it stops as soon
+/// \brief This is similar to GetRCIdentityRoot but it stops as soon
/// as it finds a value with multiple uses.
static const Value *FindSingleUseIdentifiedObject(const Value *Arg) {
if (Arg->hasOneUse()) {
if (const GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Arg))
if (GEP->hasAllZeroIndices())
return FindSingleUseIdentifiedObject(GEP->getPointerOperand());
- if (IsForwarding(GetBasicInstructionClass(Arg)))
+ if (IsForwarding(GetBasicARCInstKind(Arg)))
return FindSingleUseIdentifiedObject(
cast<CallInst>(Arg)->getArgOperand(0));
if (!IsObjCIdentifiedObject(Arg))
- return 0;
+ return nullptr;
return Arg;
}
// If we found an identifiable object but it has multiple uses, but they are
// trivial uses, we can still consider this to be a single-use value.
if (IsObjCIdentifiedObject(Arg)) {
- for (Value::const_use_iterator UI = Arg->use_begin(), UE = Arg->use_end();
- UI != UE; ++UI) {
- const User *U = *UI;
- if (!U->use_empty() || StripPointerCastsAndObjCCalls(U) != Arg)
- return 0;
- }
+ for (const User *U : Arg->users())
+ if (!U->use_empty() || GetRCIdentityRoot(U) != Arg)
+ return nullptr;
return Arg;
}
- return 0;
-}
-
-/// \brief Test whether the given retainable object pointer escapes.
-///
-/// This differs from regular escape analysis in that a use as an
-/// argument to a call is not considered an escape.
-///
-static bool DoesRetainableObjPtrEscape(const User *Ptr) {
- DEBUG(dbgs() << "DoesRetainableObjPtrEscape: Target: " << *Ptr << "\n");
-
- // Walk the def-use chains.
- SmallVector<const Value *, 4> Worklist;
- Worklist.push_back(Ptr);
- // If Ptr has any operands add them as well.
- for (User::const_op_iterator I = Ptr->op_begin(), E = Ptr->op_end(); I != E;
- ++I) {
- Worklist.push_back(*I);
- }
-
- // Ensure we do not visit any value twice.
- SmallPtrSet<const Value *, 8> VisitedSet;
-
- do {
- const Value *V = Worklist.pop_back_val();
-
- DEBUG(dbgs() << "Visiting: " << *V << "\n");
-
- for (Value::const_use_iterator UI = V->use_begin(), UE = V->use_end();
- UI != UE; ++UI) {
- const User *UUser = *UI;
-
- DEBUG(dbgs() << "User: " << *UUser << "\n");
-
- // Special - Use by a call (callee or argument) is not considered
- // to be an escape.
- switch (GetBasicInstructionClass(UUser)) {
- case IC_StoreWeak:
- case IC_InitWeak:
- case IC_StoreStrong:
- case IC_Autorelease:
- case IC_AutoreleaseRV: {
- DEBUG(dbgs() << "User copies pointer arguments. Pointer Escapes!\n");
- // These special functions make copies of their pointer arguments.
- return true;
- }
- case IC_IntrinsicUser:
- // Use by the use intrinsic is not an escape.
- continue;
- case IC_User:
- case IC_None:
- // Use by an instruction which copies the value is an escape if the
- // result is an escape.
- if (isa<BitCastInst>(UUser) || isa<GetElementPtrInst>(UUser) ||
- isa<PHINode>(UUser) || isa<SelectInst>(UUser)) {
-
- if (VisitedSet.insert(UUser)) {
- DEBUG(dbgs() << "User copies value. Ptr escapes if result escapes."
- " Adding to list.\n");
- Worklist.push_back(UUser);
- } else {
- DEBUG(dbgs() << "Already visited node.\n");
- }
- continue;
- }
- // Use by a load is not an escape.
- if (isa<LoadInst>(UUser))
- continue;
- // Use by a store is not an escape if the use is the address.
- if (const StoreInst *SI = dyn_cast<StoreInst>(UUser))
- if (V != SI->getValueOperand())
- continue;
- break;
- default:
- // Regular calls and other stuff are not considered escapes.
- continue;
- }
- // Otherwise, conservatively assume an escape.
- DEBUG(dbgs() << "Assuming ptr escapes.\n");
- return true;
- }
- } while (!Worklist.empty());
-
- // No escapes found.
- DEBUG(dbgs() << "Ptr does not escape.\n");
- return false;
+ return nullptr;
}
/// This is a wrapper around getUnderlyingObjCPtr along the lines of
if (isa<AllocaInst>(P))
return true;
- if (!Visited.insert(P))
+ if (!Visited.insert(P).second)
continue;
if (const SelectInst *SI = dyn_cast<const SelectInst>(P)) {
"Number of releases after optimization");
#endif
-namespace {
- /// \enum Sequence
- ///
- /// \brief A sequence of states that a pointer may go through in which an
- /// objc_retain and objc_release are actually needed.
- enum Sequence {
- S_None,
- S_Retain, ///< objc_retain(x).
- S_CanRelease, ///< foo(x) -- x could possibly see a ref count decrement.
- S_Use, ///< any use of x.
- S_Stop, ///< like S_Release, but code motion is stopped.
- S_Release, ///< objc_release(x).
- S_MovableRelease ///< objc_release(x), !clang.imprecise_release.
- };
-
- raw_ostream &operator<<(raw_ostream &OS, const Sequence S)
- LLVM_ATTRIBUTE_UNUSED;
- raw_ostream &operator<<(raw_ostream &OS, const Sequence S) {
- switch (S) {
- case S_None:
- return OS << "S_None";
- case S_Retain:
- return OS << "S_Retain";
- case S_CanRelease:
- return OS << "S_CanRelease";
- case S_Use:
- return OS << "S_Use";
- case S_Release:
- return OS << "S_Release";
- case S_MovableRelease:
- return OS << "S_MovableRelease";
- case S_Stop:
- return OS << "S_Stop";
- }
- llvm_unreachable("Unknown sequence type.");
- }
-}
-
-static Sequence MergeSeqs(Sequence A, Sequence B, bool TopDown) {
- // The easy cases.
- if (A == B)
- return A;
- if (A == S_None || B == S_None)
- return S_None;
-
- if (A > B) std::swap(A, B);
- if (TopDown) {
- // Choose the side which is further along in the sequence.
- if ((A == S_Retain || A == S_CanRelease) &&
- (B == S_CanRelease || B == S_Use))
- return B;
- } else {
- // Choose the side which is further along in the sequence.
- if ((A == S_Use || A == S_CanRelease) &&
- (B == S_Use || B == S_Release || B == S_Stop || B == S_MovableRelease))
- return A;
- // If both sides are releases, choose the more conservative one.
- if (A == S_Stop && (B == S_Release || B == S_MovableRelease))
- return A;
- if (A == S_Release && B == S_MovableRelease)
- return A;
- }
-
- return S_None;
-}
-
-namespace {
- /// \brief Unidirectional information about either a
- /// retain-decrement-use-release sequence or release-use-decrement-retain
- /// reverse sequence.
- struct RRInfo {
- /// After an objc_retain, the reference count of the referenced
- /// object is known to be positive. Similarly, before an objc_release, the
- /// reference count of the referenced object is known to be positive. If
- /// there are retain-release pairs in code regions where the retain count
- /// is known to be positive, they can be eliminated, regardless of any side
- /// effects between them.
- ///
- /// Also, a retain+release pair nested within another retain+release
- /// pair all on the known same pointer value can be eliminated, regardless
- /// of any intervening side effects.
- ///
- /// KnownSafe is true when either of these conditions is satisfied.
- bool KnownSafe;
-
- /// True of the objc_release calls are all marked with the "tail" keyword.
- bool IsTailCallRelease;
-
- /// If the Calls are objc_release calls and they all have a
- /// clang.imprecise_release tag, this is the metadata tag.
- MDNode *ReleaseMetadata;
-
- /// For a top-down sequence, the set of objc_retains or
- /// objc_retainBlocks. For bottom-up, the set of objc_releases.
- SmallPtrSet<Instruction *, 2> Calls;
-
- /// The set of optimal insert positions for moving calls in the opposite
- /// sequence.
- SmallPtrSet<Instruction *, 2> ReverseInsertPts;
-
- /// If this is true, we cannot perform code motion but can still remove
- /// retain/release pairs.
- bool CFGHazardAfflicted;
-
- RRInfo() :
- KnownSafe(false), IsTailCallRelease(false), ReleaseMetadata(0),
- CFGHazardAfflicted(false) {}
-
- void clear();
-
- /// Conservatively merge the two RRInfo. Returns true if a partial merge has
- /// occured, false otherwise.
- bool Merge(const RRInfo &Other);
-
- };
-}
-
-void RRInfo::clear() {
- KnownSafe = false;
- IsTailCallRelease = false;
- ReleaseMetadata = 0;
- Calls.clear();
- ReverseInsertPts.clear();
- CFGHazardAfflicted = false;
-}
-
-bool RRInfo::Merge(const RRInfo &Other) {
- // Conservatively merge the ReleaseMetadata information.
- if (ReleaseMetadata != Other.ReleaseMetadata)
- ReleaseMetadata = 0;
-
- // Conservatively merge the boolean state.
- KnownSafe &= Other.KnownSafe;
- IsTailCallRelease &= Other.IsTailCallRelease;
- CFGHazardAfflicted |= Other.CFGHazardAfflicted;
-
- // Merge the call sets.
- Calls.insert(Other.Calls.begin(), Other.Calls.end());
-
- // Merge the insert point sets. If there are any differences,
- // that makes this a partial merge.
- bool Partial = ReverseInsertPts.size() != Other.ReverseInsertPts.size();
- for (SmallPtrSet<Instruction *, 2>::const_iterator
- I = Other.ReverseInsertPts.begin(),
- E = Other.ReverseInsertPts.end(); I != E; ++I)
- Partial |= ReverseInsertPts.insert(*I);
- return Partial;
-}
-
-namespace {
- /// \brief This class summarizes several per-pointer runtime properties which
- /// are propogated through the flow graph.
- class PtrState {
- /// True if the reference count is known to be incremented.
- bool KnownPositiveRefCount;
-
- /// True if we've seen an opportunity for partial RR elimination, such as
- /// pushing calls into a CFG triangle or into one side of a CFG diamond.
- bool Partial;
-
- /// The current position in the sequence.
- Sequence Seq : 8;
-
- public:
- /// Unidirectional information about the current sequence.
- ///
- /// TODO: Encapsulate this better.
- RRInfo RRI;
-
- PtrState() : KnownPositiveRefCount(false), Partial(false),
- Seq(S_None) {}
-
-
- bool IsKnownSafe() const {
- return RRI.KnownSafe;
- }
-
- void SetKnownSafe(const bool NewValue) {
- RRI.KnownSafe = NewValue;
- }
-
- bool IsTailCallRelease() const {
- return RRI.IsTailCallRelease;
- }
-
- void SetTailCallRelease(const bool NewValue) {
- RRI.IsTailCallRelease = NewValue;
- }
-
- bool IsTrackingImpreciseReleases() {
- return RRI.ReleaseMetadata != 0;
- }
-
- const MDNode *GetReleaseMetadata() const {
- return RRI.ReleaseMetadata;
- }
-
- void SetReleaseMetadata(MDNode *NewValue) {
- RRI.ReleaseMetadata = NewValue;
- }
-
- bool IsCFGHazardAfflicted() const {
- return RRI.CFGHazardAfflicted;
- }
-
- void SetCFGHazardAfflicted(const bool NewValue) {
- RRI.CFGHazardAfflicted = NewValue;
- }
-
- void SetKnownPositiveRefCount() {
- DEBUG(dbgs() << "Setting Known Positive.\n");
- KnownPositiveRefCount = true;
- }
-
- void ClearKnownPositiveRefCount() {
- DEBUG(dbgs() << "Clearing Known Positive.\n");
- KnownPositiveRefCount = false;
- }
-
- bool HasKnownPositiveRefCount() const {
- return KnownPositiveRefCount;
- }
-
- void SetSeq(Sequence NewSeq) {
- DEBUG(dbgs() << "Old: " << Seq << "; New: " << NewSeq << "\n");
- Seq = NewSeq;
- }
-
- Sequence GetSeq() const {
- return Seq;
- }
-
- void ClearSequenceProgress() {
- ResetSequenceProgress(S_None);
- }
-
- void ResetSequenceProgress(Sequence NewSeq) {
- DEBUG(dbgs() << "Resetting sequence progress.\n");
- SetSeq(NewSeq);
- Partial = false;
- RRI.clear();
- }
-
- void Merge(const PtrState &Other, bool TopDown);
- };
-}
-
-void
-PtrState::Merge(const PtrState &Other, bool TopDown) {
- Seq = MergeSeqs(Seq, Other.Seq, TopDown);
- KnownPositiveRefCount &= Other.KnownPositiveRefCount;
-
- // If we're not in a sequence (anymore), drop all associated state.
- if (Seq == S_None) {
- Partial = false;
- RRI.clear();
- } else if (Partial || Other.Partial) {
- // If we're doing a merge on a path that's previously seen a partial
- // merge, conservatively drop the sequence, to avoid doing partial
- // RR elimination. If the branch predicates for the two merge differ,
- // mixing them is unsafe.
- ClearSequenceProgress();
- } else {
- // Otherwise merge the other PtrState's RRInfo into our RRInfo. At this
- // point, we know that currently we are not partial. Stash whether or not
- // the merge operation caused us to undergo a partial merging of reverse
- // insertion points.
- Partial = RRI.Merge(Other.RRI);
- }
-}
-
namespace {
/// \brief Per-BasicBlock state.
class BBState {
unsigned BottomUpPathCount;
/// A type for PerPtrTopDown and PerPtrBottomUp.
- typedef MapVector<const Value *, PtrState> MapTy;
+ typedef BlotMapVector<const Value *, PtrState> MapTy;
/// The top-down traversal uses this to record information known about a
/// pointer at the bottom of each block.
SmallVector<BasicBlock *, 2> Succs;
public:
- BBState() : TopDownPathCount(0), BottomUpPathCount(0) {}
+ static const unsigned OverflowOccurredValue;
+
+ BBState() : TopDownPathCount(0), BottomUpPathCount(0) { }
typedef MapTy::iterator ptr_iterator;
typedef MapTy::const_iterator ptr_const_iterator;
/// which pass through this block. This is only valid after both the
/// top-down and bottom-up traversals are complete.
///
- /// Returns true if overflow occured. Returns false if overflow did not
+ /// Returns true if overflow occurred. Returns false if overflow did not
/// occur.
bool GetAllPathCountWithOverflow(unsigned &PathCount) const {
- assert(TopDownPathCount != 0);
- assert(BottomUpPathCount != 0);
+ if (TopDownPathCount == OverflowOccurredValue ||
+ BottomUpPathCount == OverflowOccurredValue)
+ return true;
unsigned long long Product =
(unsigned long long)TopDownPathCount*BottomUpPathCount;
- PathCount = Product;
- // Overflow occured if any of the upper bits of Product are set.
- return Product >> 32;
+ // Overflow occurred if any of the upper bits of Product are set or if all
+ // the lower bits of Product are all set.
+ return (Product >> 32) ||
+ ((PathCount = Product) == OverflowOccurredValue);
}
// Specialized CFG utilities.
typedef SmallVectorImpl<BasicBlock *>::const_iterator edge_iterator;
- edge_iterator pred_begin() { return Preds.begin(); }
- edge_iterator pred_end() { return Preds.end(); }
- edge_iterator succ_begin() { return Succs.begin(); }
- edge_iterator succ_end() { return Succs.end(); }
+ edge_iterator pred_begin() const { return Preds.begin(); }
+ edge_iterator pred_end() const { return Preds.end(); }
+ edge_iterator succ_begin() const { return Succs.begin(); }
+ edge_iterator succ_end() const { return Succs.end(); }
void addSucc(BasicBlock *Succ) { Succs.push_back(Succ); }
void addPred(BasicBlock *Pred) { Preds.push_back(Pred); }
bool isExit() const { return Succs.empty(); }
};
+
+ const unsigned BBState::OverflowOccurredValue = 0xffffffff;
}
void BBState::InitFromPred(const BBState &Other) {
/// The top-down traversal uses this to merge information about predecessors to
/// form the initial state for a new block.
void BBState::MergePred(const BBState &Other) {
+ if (TopDownPathCount == OverflowOccurredValue)
+ return;
+
// Other.TopDownPathCount can be 0, in which case it is either dead or a
// loop backedge. Loop backedges are special.
TopDownPathCount += Other.TopDownPathCount;
+ // In order to be consistent, we clear the top down pointers when by adding
+ // TopDownPathCount becomes OverflowOccurredValue even though "true" overflow
+ // has not occurred.
+ if (TopDownPathCount == OverflowOccurredValue) {
+ clearTopDownPointers();
+ return;
+ }
+
// Check for overflow. If we have overflow, fall back to conservative
// behavior.
if (TopDownPathCount < Other.TopDownPathCount) {
+ TopDownPathCount = OverflowOccurredValue;
clearTopDownPointers();
return;
}
// For each entry in the other set, if our set has an entry with the same key,
// merge the entries. Otherwise, copy the entry and merge it with an empty
// entry.
- for (ptr_const_iterator MI = Other.top_down_ptr_begin(),
- ME = Other.top_down_ptr_end(); MI != ME; ++MI) {
+ for (auto MI = Other.top_down_ptr_begin(), ME = Other.top_down_ptr_end();
+ MI != ME; ++MI) {
std::pair<ptr_iterator, bool> Pair = PerPtrTopDown.insert(*MI);
Pair.first->second.Merge(Pair.second ? PtrState() : MI->second,
/*TopDown=*/true);
// For each entry in our set, if the other set doesn't have an entry with the
// same key, force it to merge with an empty entry.
- for (ptr_iterator MI = top_down_ptr_begin(),
- ME = top_down_ptr_end(); MI != ME; ++MI)
+ for (auto MI = top_down_ptr_begin(), ME = top_down_ptr_end(); MI != ME; ++MI)
if (Other.PerPtrTopDown.find(MI->first) == Other.PerPtrTopDown.end())
MI->second.Merge(PtrState(), /*TopDown=*/true);
}
/// The bottom-up traversal uses this to merge information about successors to
/// form the initial state for a new block.
void BBState::MergeSucc(const BBState &Other) {
+ if (BottomUpPathCount == OverflowOccurredValue)
+ return;
+
// Other.BottomUpPathCount can be 0, in which case it is either dead or a
// loop backedge. Loop backedges are special.
BottomUpPathCount += Other.BottomUpPathCount;
+ // In order to be consistent, we clear the top down pointers when by adding
+ // BottomUpPathCount becomes OverflowOccurredValue even though "true" overflow
+ // has not occurred.
+ if (BottomUpPathCount == OverflowOccurredValue) {
+ clearBottomUpPointers();
+ return;
+ }
+
// Check for overflow. If we have overflow, fall back to conservative
// behavior.
if (BottomUpPathCount < Other.BottomUpPathCount) {
+ BottomUpPathCount = OverflowOccurredValue;
clearBottomUpPointers();
return;
}
// For each entry in the other set, if our set has an entry with the
// same key, merge the entries. Otherwise, copy the entry and merge
// it with an empty entry.
- for (ptr_const_iterator MI = Other.bottom_up_ptr_begin(),
- ME = Other.bottom_up_ptr_end(); MI != ME; ++MI) {
+ for (auto MI = Other.bottom_up_ptr_begin(), ME = Other.bottom_up_ptr_end();
+ MI != ME; ++MI) {
std::pair<ptr_iterator, bool> Pair = PerPtrBottomUp.insert(*MI);
Pair.first->second.Merge(Pair.second ? PtrState() : MI->second,
/*TopDown=*/false);
// For each entry in our set, if the other set doesn't have an entry
// with the same key, force it to merge with an empty entry.
- for (ptr_iterator MI = bottom_up_ptr_begin(),
- ME = bottom_up_ptr_end(); MI != ME; ++MI)
+ for (auto MI = bottom_up_ptr_begin(), ME = bottom_up_ptr_end(); MI != ME;
+ ++MI)
if (Other.PerPtrBottomUp.find(MI->first) == Other.PerPtrBottomUp.end())
MI->second.Merge(PtrState(), /*TopDown=*/false);
}
/// arc annotation processor tool. If the function is an
static MDString *AppendMDNodeToSourcePtr(unsigned NodeId,
Value *Ptr) {
- MDString *Hash = 0;
+ MDString *Hash = nullptr;
// If pointer is a result of an instruction and it does not have a source
// MDNode it, attach a new MDNode onto it. If pointer is a result of
// an instruction and does have a source MDNode attached to it, return a
// reference to said Node. Otherwise just return 0.
- if (Instruction *Inst = dyn_cast<Instruction>(Ptr)) {
+ if (auto *Inst = dyn_cast<Instruction>(Ptr)) {
MDNode *Node;
if (!(Node = Inst->getMetadata(NodeId))) {
// We do not have any node. Generate and attatch the hash MDString to the
"An ARCAnnotationProvenanceSourceMDKind can only have 1 operand.");
Hash = cast<MDString>(Node->getOperand(0));
}
- } else if (
Argument *Arg = dyn_cast<Argument>(Ptr)) {
+ } else if (
auto *Arg = dyn_cast<Argument>(Ptr)) {
std::string str;
raw_string_ostream os(str);
os << "(" << Arg->getParent()->getName() << ",%" << Arg->getName()
MDString *PtrSourceMDNodeID,
Sequence OldSeq,
Sequence NewSeq) {
- MDNode *Node = 0;
- Value *tmp[3] = {PtrSourceMDNodeID,
- SequenceToMDString(Inst->getContext(),
- OldSeq),
- SequenceToMDString(Inst->getContext(),
- NewSeq)};
- Node = MDNode::get(Inst->getContext(),
- ArrayRef<Value*>(tmp, 3));
+ MDNode *Node = nullptr;
+ Metadata *tmp[3] = {PtrSourceMDNodeID,
+ SequenceToMDString(Inst->getContext(), OldSeq),
+ SequenceToMDString(Inst->getContext(), NewSeq)};
+ Node = MDNode::get(Inst->getContext(), tmp);
Inst->setMetadata(NodeId, Node);
}
Type *I8X = PointerType::getUnqual(Type::getInt8Ty(C));
Type *I8XX = PointerType::getUnqual(I8X);
Type *Params[] = {I8XX, I8XX};
- FunctionType *FTy = FunctionType::get(Type::getVoidTy(C),
- ArrayRef<Type*>(Params, 2),
+ FunctionType *FTy = FunctionType::get(Type::getVoidTy(C), Params,
/*isVarArg=*/false);
Constant *Callee = M->getOrInsertFunction(Name, FTy);
Value *PtrName;
StringRef Tmp = Ptr->getName();
- if (0 == (PtrName = M->getGlobalVariable(Tmp, true))) {
+ if (nullptr == (PtrName = M->getGlobalVariable(Tmp, true))) {
Value *ActualPtrName = Builder.CreateGlobalStringPtr(Tmp,
Tmp + "_STR");
PtrName = new GlobalVariable(*M, I8X, true, GlobalVariable::InternalLinkage,
Value *S;
std::string SeqStr = SequenceToString(Seq);
- if (0 == (S = M->getGlobalVariable(SeqStr, true))) {
+ if (nullptr == (S = M->getGlobalVariable(SeqStr, true))) {
Value *ActualPtrName = Builder.CreateGlobalStringPtr(SeqStr,
SeqStr + "_STR");
S = new GlobalVariable(*M, I8X, true, GlobalVariable::InternalLinkage,
Type *I8X = PointerType::getUnqual(Type::getInt8Ty(C));
Type *I8XX = PointerType::getUnqual(I8X);
Type *Params[] = {I8XX, I8XX};
- FunctionType *FTy = FunctionType::get(Type::getVoidTy(C),
- ArrayRef<Type*>(Params, 2),
+ FunctionType *FTy = FunctionType::get(Type::getVoidTy(C), Params,
/*isVarArg=*/false);
Constant *Callee = M->getOrInsertFunction(Name, FTy);
- IRBuilder<> Builder(BB, llvm::prior(BB->end()));
+ IRBuilder<> Builder(BB, std::prev(BB->end()));
Value *PtrName;
StringRef Tmp = Ptr->getName();
- if (0 == (PtrName = M->getGlobalVariable(Tmp, true))) {
+ if (nullptr == (PtrName = M->getGlobalVariable(Tmp, true))) {
Value *ActualPtrName = Builder.CreateGlobalStringPtr(Tmp,
Tmp + "_STR");
PtrName = new GlobalVariable(*M, I8X, true, GlobalVariable::InternalLinkage,
Value *S;
std::string SeqStr = SequenceToString(Seq);
- if (0 == (S = M->getGlobalVariable(SeqStr, true))) {
+ if (nullptr == (S = M->getGlobalVariable(SeqStr, true))) {
Value *ActualPtrName = Builder.CreateGlobalStringPtr(SeqStr,
SeqStr + "_STR");
S = new GlobalVariable(*M, I8X, true, GlobalVariable::InternalLinkage,
// llvm-arc-annotation-processor tool to cross reference where the source
// pointer is in the LLVM IR since the LLVM IR parser does not submit such
// information via debug info for backends to use (since why would anyone
- // need such a thing from LLVM IR besides in non standard cases
+ // need such a thing from LLVM IR besides in non-standard cases
// [i.e. this]).
MDString *SourcePtrMDNode =
AppendMDNodeToSourcePtr(PtrMDId, Ptr);
class ObjCARCOpt : public FunctionPass {
bool Changed;
ProvenanceAnalysis PA;
+ ARCRuntimeEntryPoints EP;
// This is used to track if a pointer is stored into an alloca.
DenseSet<const Value *> MultiOwnersSet;
/// A flag indicating whether this optimization pass should run.
bool Run;
- /// Declarations for ObjC runtime functions, for use in creating calls to
- /// them. These are initialized lazily to avoid cluttering up the Module
- /// with unused declarations.
-
- /// Declaration for ObjC runtime function objc_autoreleaseReturnValue.
- Constant *AutoreleaseRVCallee;
- /// Declaration for ObjC runtime function objc_release.
- Constant *ReleaseCallee;
- /// Declaration for ObjC runtime function objc_retain.
- Constant *RetainCallee;
- /// Declaration for ObjC runtime function objc_retainBlock.
- Constant *RetainBlockCallee;
- /// Declaration for ObjC runtime function objc_autorelease.
- Constant *AutoreleaseCallee;
-
/// Flags which determine whether each of the interesting runtine functions
/// is in fact used in the current function.
unsigned UsedInThisFunction;
unsigned ARCAnnotationProvenanceSourceMDKind;
#endif // ARC_ANNOATIONS
- Constant *getAutoreleaseRVCallee(Module *M);
- Constant *getReleaseCallee(Module *M);
- Constant *getRetainCallee(Module *M);
- Constant *getRetainBlockCallee(Module *M);
- Constant *getAutoreleaseCallee(Module *M);
-
- bool IsRetainBlockOptimizable(const Instruction *Inst);
-
bool OptimizeRetainRVCall(Function &F, Instruction *RetainRV);
void OptimizeAutoreleaseRVCall(Function &F, Instruction *AutoreleaseRV,
- InstructionClass &Class);
- bool OptimizeRetainBlockCall(Function &F, Instruction *RetainBlock,
- InstructionClass &Class);
+ ARCInstKind &Class);
void OptimizeIndividualCalls(Function &F);
void CheckForCFGHazards(const BasicBlock *BB,
DenseMap<const BasicBlock *, BBState> &BBStates,
BBState &MyStates) const;
- bool VisitInstructionBottomUp(Instruction *Inst,
- BasicBlock *BB,
- MapVector<Value *, RRInfo> &Retains,
+ bool VisitInstructionBottomUp(Instruction *Inst, BasicBlock *BB,
+ BlotMapVector<Value *, RRInfo> &Retains,
BBState &MyStates);
bool VisitBottomUp(BasicBlock *BB,
DenseMap<const BasicBlock *, BBState> &BBStates,
- MapVector<Value *, RRInfo> &Retains);
+ BlotMapVector<Value *, RRInfo> &Retains);
bool VisitInstructionTopDown(Instruction *Inst,
DenseMap<Value *, RRInfo> &Releases,
BBState &MyStates);
bool VisitTopDown(BasicBlock *BB,
DenseMap<const BasicBlock *, BBState> &BBStates,
DenseMap<Value *, RRInfo> &Releases);
- bool Visit(Function &F,
- DenseMap<const BasicBlock *, BBState> &BBStates,
- MapVector<Value *, RRInfo> &Retains,
+ bool Visit(Function &F, DenseMap<const BasicBlock *, BBState> &BBStates,
+ BlotMapVector<Value *, RRInfo> &Retains,
DenseMap<Value *, RRInfo> &Releases);
void MoveCalls(Value *Arg, RRInfo &RetainsToMove, RRInfo &ReleasesToMove,
- MapVector<Value *, RRInfo> &Retains,
+ BlotMapVector<Value *, RRInfo> &Retains,
DenseMap<Value *, RRInfo> &Releases,
- SmallVectorImpl<Instruction *> &DeadInsts,
- Module *M);
+ SmallVectorImpl<Instruction *> &DeadInsts, Module *M);
bool ConnectTDBUTraversals(DenseMap<const BasicBlock *, BBState> &BBStates,
- MapVector<Value *, RRInfo> &Retains,
- DenseMap<Value *, RRInfo> &Releases,
- Module *M,
- SmallVector<Instruction *, 4> &NewRetains,
- SmallVector<Instruction *, 4> &NewReleases,
- SmallVector<Instruction *, 8> &DeadInsts,
- RRInfo &RetainsToMove,
- RRInfo &ReleasesToMove,
- Value *Arg,
- bool KnownSafe,
+ BlotMapVector<Value *, RRInfo> &Retains,
+ DenseMap<Value *, RRInfo> &Releases, Module *M,
+ SmallVectorImpl<Instruction *> &NewRetains,
+ SmallVectorImpl<Instruction *> &NewReleases,
+ SmallVectorImpl<Instruction *> &DeadInsts,
+ RRInfo &RetainsToMove, RRInfo &ReleasesToMove,
+ Value *Arg, bool KnownSafe,
bool &AnyPairsCompletelyEliminated);
bool PerformCodePlacement(DenseMap<const BasicBlock *, BBState> &BBStates,
- MapVector<Value *, RRInfo> &Retains,
- DenseMap<Value *, RRInfo> &Releases,
- Module *M);
+ BlotMapVector<Value *, RRInfo> &Retains,
+ DenseMap<Value *, RRInfo> &Releases, Module *M);
void OptimizeWeakCalls(Function &F);
void GatherStatistics(Function &F, bool AfterOptimization = false);
#endif
- virtual void getAnalysisUsage(AnalysisUsage &AU) const;
- virtual bool doInitialization(Module &M);
- virtual bool runOnFunction(Function &F);
- virtual void releaseMemory();
+ void getAnalysisUsage(AnalysisUsage &AU) const override;
+ bool doInitialization(Module &M) override;
+ bool runOnFunction(Function &F) override;
+ void releaseMemory() override;
public:
static char ID;
AU.setPreservesCFG();
}
-bool ObjCARCOpt::IsRetainBlockOptimizable(const Instruction *Inst) {
- // Without the magic metadata tag, we have to assume this might be an
- // objc_retainBlock call inserted to convert a block pointer to an id,
- // in which case it really is needed.
- if (!Inst->getMetadata(CopyOnEscapeMDKind))
- return false;
-
- // If the pointer "escapes" (not including being used in a call),
- // the copy may be needed.
- if (DoesRetainableObjPtrEscape(Inst))
- return false;
-
- // Otherwise, it's not needed.
- return true;
-}
-
-Constant *ObjCARCOpt::getAutoreleaseRVCallee(Module *M) {
- if (!AutoreleaseRVCallee) {
- LLVMContext &C = M->getContext();
- Type *I8X = PointerType::getUnqual(Type::getInt8Ty(C));
- Type *Params[] = { I8X };
- FunctionType *FTy = FunctionType::get(I8X, Params, /*isVarArg=*/false);
- AttributeSet Attribute =
- AttributeSet().addAttribute(M->getContext(), AttributeSet::FunctionIndex,
- Attribute::NoUnwind);
- AutoreleaseRVCallee =
- M->getOrInsertFunction("objc_autoreleaseReturnValue", FTy,
- Attribute);
- }
- return AutoreleaseRVCallee;
-}
-
-Constant *ObjCARCOpt::getReleaseCallee(Module *M) {
- if (!ReleaseCallee) {
- LLVMContext &C = M->getContext();
- Type *Params[] = { PointerType::getUnqual(Type::getInt8Ty(C)) };
- AttributeSet Attribute =
- AttributeSet().addAttribute(M->getContext(), AttributeSet::FunctionIndex,
- Attribute::NoUnwind);
- ReleaseCallee =
- M->getOrInsertFunction(
- "objc_release",
- FunctionType::get(Type::getVoidTy(C), Params, /*isVarArg=*/false),
- Attribute);
- }
- return ReleaseCallee;
-}
-
-Constant *ObjCARCOpt::getRetainCallee(Module *M) {
- if (!RetainCallee) {
- LLVMContext &C = M->getContext();
- Type *Params[] = { PointerType::getUnqual(Type::getInt8Ty(C)) };
- AttributeSet Attribute =
- AttributeSet().addAttribute(M->getContext(), AttributeSet::FunctionIndex,
- Attribute::NoUnwind);
- RetainCallee =
- M->getOrInsertFunction(
- "objc_retain",
- FunctionType::get(Params[0], Params, /*isVarArg=*/false),
- Attribute);
- }
- return RetainCallee;
-}
-
-Constant *ObjCARCOpt::getRetainBlockCallee(Module *M) {
- if (!RetainBlockCallee) {
- LLVMContext &C = M->getContext();
- Type *Params[] = { PointerType::getUnqual(Type::getInt8Ty(C)) };
- // objc_retainBlock is not nounwind because it calls user copy constructors
- // which could theoretically throw.
- RetainBlockCallee =
- M->getOrInsertFunction(
- "objc_retainBlock",
- FunctionType::get(Params[0], Params, /*isVarArg=*/false),
- AttributeSet());
- }
- return RetainBlockCallee;
-}
-
-Constant *ObjCARCOpt::getAutoreleaseCallee(Module *M) {
- if (!AutoreleaseCallee) {
- LLVMContext &C = M->getContext();
- Type *Params[] = { PointerType::getUnqual(Type::getInt8Ty(C)) };
- AttributeSet Attribute =
- AttributeSet().addAttribute(M->getContext(), AttributeSet::FunctionIndex,
- Attribute::NoUnwind);
- AutoreleaseCallee =
- M->getOrInsertFunction(
- "objc_autorelease",
- FunctionType::get(Params[0], Params, /*isVarArg=*/false),
- Attribute);
- }
- return AutoreleaseCallee;
-}
-
/// Turn objc_retainAutoreleasedReturnValue into objc_retain if the operand is
/// not a return value. Or, if it can be paired with an
/// objc_autoreleaseReturnValue, delete the pair and return true.
bool
ObjCARCOpt::OptimizeRetainRVCall(Function &F, Instruction *RetainRV) {
// Check for the argument being from an immediately preceding call or invoke.
- const Value *Arg = GetObjCArg(RetainRV);
+ const Value *Arg = GetArgRCIdentityRoot(RetainRV);
ImmutableCallSite CS(Arg);
if (const Instruction *Call = CS.getInstruction()) {
if (Call->getParent() == RetainRV->getParent()) {
BasicBlock::iterator I = RetainRV, Begin = RetainRV->getParent()->begin();
if (I != Begin) {
do --I; while (I != Begin && IsNoopInstruction(I));
- if (GetBasicInstructionClass(I) == IC_AutoreleaseRV &&
- GetObjCArg(I) == Arg) {
+ if (GetBasicARCInstKind(I) == ARCInstKind::AutoreleaseRV &&
+ GetArgRCIdentityRoot(I) == Arg) {
Changed = true;
++NumPeeps;
"objc_retain since the operand is not a return value.\n"
"Old = " << *RetainRV << "\n");
- cast<CallInst>(RetainRV)->setCalledFunction(getRetainCallee(F.getParent()));
+ Constant *NewDecl = EP.get(ARCRuntimeEntryPoints::EPT_Retain);
+ cast<CallInst>(RetainRV)->setCalledFunction(NewDecl);
DEBUG(dbgs() << "New = " << *RetainRV << "\n");
/// Turn objc_autoreleaseReturnValue into objc_autorelease if the result is not
/// used as a return value.
-void
-ObjCARCOpt::OptimizeAutoreleaseRVCall(Function &F, Instruction *AutoreleaseRV,
- InstructionClass &Class) {
+void ObjCARCOpt::OptimizeAutoreleaseRVCall(Function &F,
+ Instruction *AutoreleaseRV,
+ ARCInstKind &Class) {
// Check for a return of the pointer value.
- const Value *Ptr = GetObjCArg(AutoreleaseRV);
+ const Value *Ptr = GetArgRCIdentityRoot(AutoreleaseRV);
SmallVector<const Value *, 2> Users;
Users.push_back(Ptr);
do {
Ptr = Users.pop_back_val();
- for (Value::const_use_iterator UI = Ptr->use_begin(), UE = Ptr->use_end();
- UI != UE; ++UI) {
- const User *I = *UI;
- if (isa<ReturnInst>(I) || GetBasicInstructionClass(I) == IC_RetainRV)
+ for (const User *U : Ptr->users()) {
+ if (isa<ReturnInst>(U) || GetBasicARCInstKind(U) == ARCInstKind::RetainRV)
return;
- if (isa<BitCastInst>(I))
- Users.push_back(I);
+ if (isa<BitCastInst>(U))
+ Users.push_back(U);
}
} while (!Users.empty());
"Old = " << *AutoreleaseRV << "\n");
CallInst *AutoreleaseRVCI = cast<CallInst>(AutoreleaseRV);
- AutoreleaseRVCI->
- setCalledFunction(getAutoreleaseCallee(F.getParent()));
+ Constant *NewDecl = EP.get(ARCRuntimeEntryPoints::EPT_Autorelease);
+ AutoreleaseRVCI->setCalledFunction(NewDecl);
AutoreleaseRVCI->setTailCall(false); // Never tail call objc_autorelease.
- Class = IC_Autorelease;
+ Class = ARCInstKind::Autorelease;
DEBUG(dbgs() << "New: " << *AutoreleaseRV << "\n");
}
-// \brief Attempt to strength reduce objc_retainBlock calls to objc_retain
-// calls.
-//
-// Specifically: If an objc_retainBlock call has the copy_on_escape metadata and
-// does not escape (following the rules of block escaping), strength reduce the
-// objc_retainBlock to an objc_retain.
-//
-// TODO: If an objc_retainBlock call is dominated period by a previous
-// objc_retainBlock call, strength reduce the objc_retainBlock to an
-// objc_retain.
-bool
-ObjCARCOpt::OptimizeRetainBlockCall(Function &F, Instruction *Inst,
- InstructionClass &Class) {
- assert(GetBasicInstructionClass(Inst) == Class);
- assert(IC_RetainBlock == Class);
-
- // If we can not optimize Inst, return false.
- if (!IsRetainBlockOptimizable(Inst))
- return false;
-
- Changed = true;
- ++NumPeeps;
-
- DEBUG(dbgs() << "Strength reduced retainBlock => retain.\n");
- DEBUG(dbgs() << "Old: " << *Inst << "\n");
- CallInst *RetainBlock = cast<CallInst>(Inst);
- RetainBlock->setCalledFunction(getRetainCallee(F.getParent()));
- // Remove copy_on_escape metadata.
- RetainBlock->setMetadata(CopyOnEscapeMDKind, 0);
- Class = IC_Retain;
- DEBUG(dbgs() << "New: " << *Inst << "\n");
- return true;
-}
-
/// Visit each call, one at a time, and make simplifications without doing any
/// additional analysis.
void ObjCARCOpt::OptimizeIndividualCalls(Function &F) {
for (inst_iterator I = inst_begin(&F), E = inst_end(&F); I != E; ) {
Instruction *Inst = &*I++;
- InstructionClass Class = GetBasicInstructionClass(Inst);
+ ARCInstKind Class = GetBasicARCInstKind(Inst);
DEBUG(dbgs() << "Visiting: Class: " << Class << "; " << *Inst << "\n");
// There are gray areas here, as the ability to cast reference-counted
// pointers to raw void* and back allows code to break ARC assumptions,
// however these are currently considered to be unimportant.
- case IC_NoopCast:
+ case ARCInstKind::NoopCast:
Changed = true;
++NumNoops;
DEBUG(dbgs() << "Erasing no-op cast: " << *Inst << "\n");
continue;
// If the pointer-to-weak-pointer is null, it's undefined behavior.
- case IC_StoreWeak:
- case IC_LoadWeak:
- case IC_LoadWeakRetained:
- case IC_InitWeak:
- case IC_DestroyWeak: {
+ case ARCInstKind::StoreWeak:
+ case ARCInstKind::LoadWeak:
+ case ARCInstKind::LoadWeakRetained:
+ case ARCInstKind::InitWeak:
+ case ARCInstKind::DestroyWeak: {
CallInst *CI = cast<CallInst>(Inst);
if (IsNullOrUndef(CI->getArgOperand(0))) {
Changed = true;
}
break;
}
- case IC_CopyWeak:
- case IC_MoveWeak: {
+ case ARCInstKind::CopyWeak:
+ case ARCInstKind::MoveWeak: {
CallInst *CI = cast<CallInst>(Inst);
if (IsNullOrUndef(CI->getArgOperand(0)) ||
IsNullOrUndef(CI->getArgOperand(1))) {
}
break;
}
- case IC_RetainBlock:
- // If we strength reduce an objc_retainBlock to an objc_retain, continue
- // onto the objc_retain peephole optimizations. Otherwise break.
- OptimizeRetainBlockCall(F, Inst, Class);
- break;
- case IC_RetainRV:
+ case ARCInstKind::RetainRV:
if (OptimizeRetainRVCall(F, Inst))
continue;
break;
- case IC_AutoreleaseRV:
+ case ARCInstKind::AutoreleaseRV:
OptimizeAutoreleaseRVCall(F, Inst, Class);
break;
}
// Create the declaration lazily.
LLVMContext &C = Inst->getContext();
- CallInst *NewCall =
- CallInst::Create(getReleaseCallee(F.getParent()),
- Call->getArgOperand(0), "", Call);
+
+ Constant *Decl = EP.get(ARCRuntimeEntryPoints::EPT_Release);
+ CallInst *NewCall = CallInst::Create(Decl, Call->getArgOperand(0), "",
+ Call);
NewCall->setMetadata(ImpreciseReleaseMDKind, MDNode::get(C, None));
DEBUG(dbgs() << "Replacing autorelease{,RV}(x) with objc_release(x) "
EraseInstruction(Call);
Inst = NewCall;
- Class = IC_Release;
+ Class = ARCInstKind::Release;
}
}
}
if (!IsNoopOnNull(Class)) {
- UsedInThisFunction |= 1 << Class;
+ UsedInThisFunction |= 1 << unsigned(Class);
continue;
}
- const Value *Arg = GetObjCArg(Inst);
+ const Value *Arg = GetArgRCIdentityRoot(Inst);
// ARC calls with null are no-ops. Delete them.
if (IsNullOrUndef(Arg)) {
// Keep track of which of retain, release, autorelease, and retain_block
// are actually present in this function.
- UsedInThisFunction |= 1 << Class;
+ UsedInThisFunction |= 1 << unsigned(Class);
// If Arg is a PHI, and one or more incoming values to the
// PHI are null, and the call is control-equivalent to the PHI, and there
bool HasCriticalEdges = false;
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
Value *Incoming =
- StripPointerCastsAndObjCCalls(PN->getIncomingValue(i));
+ GetRCIdentityRoot(PN->getIncomingValue(i));
if (IsNullOrUndef(Incoming))
HasNull = true;
else if (cast<TerminatorInst>(PN->getIncomingBlock(i)->back())
// Check that there is nothing that cares about the reference
// count between the call and the phi.
switch (Class) {
- case IC_Retain:
- case IC_RetainBlock:
+ case ARCInstKind::Retain:
+ case ARCInstKind::RetainBlock:
// These can always be moved up.
break;
- case IC_Release:
+ case ARCInstKind::Release:
// These can't be moved across things that care about the retain
// count.
FindDependencies(NeedsPositiveRetainCount, Arg,
Inst->getParent(), Inst,
DependingInstructions, Visited, PA);
break;
- case IC_Autorelease:
+ case ARCInstKind::Autorelease:
// These can't be moved across autorelease pool scope boundaries.
FindDependencies(AutoreleasePoolBoundary, Arg,
Inst->getParent(), Inst,
DependingInstructions, Visited, PA);
break;
- case IC_RetainRV:
- case IC_AutoreleaseRV:
+ case ARCInstKind::RetainRV:
+ case ARCInstKind::AutoreleaseRV:
// Don't move these; the RV optimization depends on the autoreleaseRV
// being tail called, and the retainRV being immediately after a call
// (which might still happen if we get lucky with codegen layout, but
Type *ParamTy = CInst->getArgOperand(0)->getType();
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
Value *Incoming =
- StripPointerCastsAndObjCCalls(PN->getIncomingValue(i));
+ GetRCIdentityRoot(PN->getIncomingValue(i));
if (!IsNullOrUndef(Incoming)) {
CallInst *Clone = cast<CallInst>(CInst->clone());
Value *Op = PN->getIncomingValue(i);
}
}
-bool
-ObjCARCOpt::VisitInstructionBottomUp(Instruction *Inst,
- BasicBlock *BB,
- MapVector<Value *, RRInfo> &Retains,
- BBState &MyStates) {
+bool ObjCARCOpt::VisitInstructionBottomUp(
+ Instruction *Inst, BasicBlock *BB, BlotMapVector<Value *, RRInfo> &Retains,
+ BBState &MyStates) {
bool NestingDetected = false;
- InstructionClass Class = GetInstructionClass(Inst);
- const Value *Arg = 0;
+ ARCInstKind Class = GetARCInstKind(Inst);
+ const Value *Arg = nullptr;
DEBUG(dbgs() << "Class: " << Class << "\n");
switch (Class) {
- case IC_Release: {
- Arg = GetObjCArg(Inst);
+ case ARCInstKind::Release: {
+ Arg = GetArgRCIdentityRoot(Inst);
PtrState &S = MyStates.getPtrBottomUpState(Arg);
S.SetReleaseMetadata(ReleaseMetadata);
S.SetKnownSafe(S.HasKnownPositiveRefCount());
S.SetTailCallRelease(cast<CallInst>(Inst)->isTailCall());
- S.RRI.Calls.insert(Inst);
+ S.InsertCall(Inst);
S.SetKnownPositiveRefCount();
break;
}
- case IC_RetainBlock:
+ case ARCInstKind::RetainBlock:
// In OptimizeIndividualCalls, we have strength reduced all optimizable
// objc_retainBlocks to objc_retains. Thus at this point any
// objc_retainBlocks that we see are not optimizable.
break;
- case IC_Retain:
- case IC_RetainRV: {
- Arg = GetObjCArg(Inst);
+ case ARCInstKind::Retain:
+ case ARCInstKind::RetainRV: {
+ Arg = GetArgRCIdentityRoot(Inst);
PtrState &S = MyStates.getPtrBottomUpState(Arg);
S.SetKnownPositiveRefCount();
// If OldSeq is not S_Use or OldSeq is S_Use and we are tracking an
// imprecise release, clear our reverse insertion points.
if (OldSeq != S_Use || S.IsTrackingImpreciseReleases())
- S.RRI.ReverseInsertPts.clear();
+ S.ClearReverseInsertPts();
// FALL THROUGH
case S_CanRelease:
- // Don't do retain+release tracking for IC_RetainRV, because it's
+ // Don't do retain+release tracking for ARCInstKind::RetainRV,
+ // because it's
// better to let it remain as the first instruction after a call.
- if (Class != IC_RetainRV)
- Retains[Inst] = S.RRI;
+ if (Class != ARCInstKind::RetainRV)
+ Retains[Inst] = S.GetRRInfo();
S.ClearSequenceProgress();
break;
case S_None:
// A retain moving bottom up can be a use.
break;
}
- case IC_AutoreleasepoolPop:
+ case ARCInstKind::AutoreleasepoolPop:
// Conservatively, clear MyStates for all known pointers.
MyStates.clearBottomUpPointers();
return NestingDetected;
- case IC_AutoreleasepoolPush:
- case IC_None:
+ case ARCInstKind::AutoreleasepoolPush:
+ case ARCInstKind::None:
// These are irrelevant.
return NestingDetected;
- case IC_User:
+ case ARCInstKind::User:
// If we have a store into an alloca of a pointer we are tracking, the
// pointer has multiple owners implying that we must be more conservative.
//
// This comes up in the context of a pointer being ``KnownSafe''. In the
- // presense of a block being initialized, the frontend will emit the
+ // presence of a block being initialized, the frontend will emit the
// objc_retain on the original pointer and the release on the pointer loaded
// from the alloca. The optimizer will through the provenance analysis
// realize that the two are related, but since we only require KnownSafe in
// one direction, will match the inner retain on the original pointer with
// the guard release on the original pointer. This is fixed by ensuring that
- // in the presense of allocas we only unconditionally remove pointers if
+ // in the presence of allocas we only unconditionally remove pointers if
// both our retain and our release are KnownSafe.
if (StoreInst *SI = dyn_cast<StoreInst>(Inst)) {
if (AreAnyUnderlyingObjectsAnAlloca(SI->getPointerOperand())) {
BBState::ptr_iterator I = MyStates.findPtrBottomUpState(
- StripPointerCastsAndObjCCalls(SI->getValueOperand()));
+ GetRCIdentityRoot(SI->getValueOperand()));
if (I != MyStates.bottom_up_ptr_end())
MultiOwnersSet.insert(I->first);
}
if (CanUse(Inst, Ptr, PA, Class)) {
DEBUG(dbgs() << "CanUse: Seq: " << Seq << "; " << *Ptr
<< "\n");
- assert(S.RRI.ReverseInsertPts.empty());
+ assert(!S.HasReverseInsertPts());
// If this is an invoke instruction, we're scanning it as part of
// one of its successor blocks, since we can't insert code after it
// in its own block, and we don't want to split critical edges.
if (isa<InvokeInst>(Inst))
- S.RRI.ReverseInsertPts.insert(BB->getFirstInsertionPt());
+ S.InsertReverseInsertPt(BB->getFirstInsertionPt());
else
- S.RRI.ReverseInsertPts.insert(llvm::next(BasicBlock::iterator(Inst)));
+ S.InsertReverseInsertPt(std::next(BasicBlock::iterator(Inst)));
S.SetSeq(S_Use);
ANNOTATE_BOTTOMUP(Inst, Ptr, Seq, S_Use);
} else if (Seq == S_Release && IsUser(Class)) {
// Non-movable releases depend on any possible objc pointer use.
S.SetSeq(S_Stop);
ANNOTATE_BOTTOMUP(Inst, Ptr, S_Release, S_Stop);
- assert(S.RRI.ReverseInsertPts.empty());
+ assert(!S.HasReverseInsertPts());
// As above; handle invoke specially.
if (isa<InvokeInst>(Inst))
- S.RRI.ReverseInsertPts.insert(BB->getFirstInsertionPt());
+ S.InsertReverseInsertPt(BB->getFirstInsertionPt());
else
- S.RRI.ReverseInsertPts.insert(llvm::next(BasicBlock::iterator(Inst)));
+ S.InsertReverseInsertPt(std::next(BasicBlock::iterator(Inst)));
}
break;
case S_Stop:
return NestingDetected;
}
-bool
-ObjCARCOpt::VisitBottomUp(BasicBlock *BB,
- DenseMap<const BasicBlock *, BBState> &BBStates,
- MapVector<Value *, RRInfo> &Retains) {
+bool ObjCARCOpt::VisitBottomUp(BasicBlock *BB,
+ DenseMap<const BasicBlock *, BBState> &BBStates,
+ BlotMapVector<Value *, RRInfo> &Retains) {
DEBUG(dbgs() << "\n== ObjCARCOpt::VisitBottomUp ==\n");
// Visit all the instructions, bottom-up.
for (BasicBlock::iterator I = BB->end(), E = BB->begin(); I != E; --I) {
- Instruction *Inst = llvm::prior(I);
+ Instruction *Inst = std::prev(I);
// Invoke instructions are visited as part of their successors (below).
if (isa<InvokeInst>(Inst))
DenseMap<Value *, RRInfo> &Releases,
BBState &MyStates) {
bool NestingDetected = false;
- InstructionClass Class = GetInstructionClass(Inst);
- const Value *Arg = 0;
+ ARCInstKind Class = GetARCInstKind(Inst);
+ const Value *Arg = nullptr;
switch (Class) {
- case IC_RetainBlock:
+ case ARCInstKind::RetainBlock:
// In OptimizeIndividualCalls, we have strength reduced all optimizable
// objc_retainBlocks to objc_retains. Thus at this point any
// objc_retainBlocks that we see are not optimizable.
break;
- case IC_Retain:
- case IC_RetainRV: {
- Arg = GetObjCArg(Inst);
+ case ARCInstKind::Retain:
+ case ARCInstKind::RetainRV: {
+ Arg = GetArgRCIdentityRoot(Inst);
PtrState &S = MyStates.getPtrTopDownState(Arg);
- // Don't do retain+release tracking for IC_RetainRV, because it's
+ // Don't do retain+release tracking for ARCInstKind::RetainRV, because
+ // it's
// better to let it remain as the first instruction after a call.
- if (Class != IC_RetainRV) {
+ if (Class != ARCInstKind::RetainRV) {
// If we see two retains in a row on the same pointer. If so, make
// a note, and we'll cicle back to revisit it after we've
// hopefully eliminated the second retain, which may allow us to
ANNOTATE_TOPDOWN(Inst, Arg, S.GetSeq(), S_Retain);
S.ResetSequenceProgress(S_Retain);
S.SetKnownSafe(S.HasKnownPositiveRefCount());
- S.RRI.Calls.insert(Inst);
+ S.InsertCall(Inst);
}
S.SetKnownPositiveRefCount();
// code below.
break;
}
- case IC_Release: {
- Arg = GetObjCArg(Inst);
+ case ARCInstKind::Release: {
+ Arg = GetArgRCIdentityRoot(Inst);
PtrState &S = MyStates.getPtrTopDownState(Arg);
S.ClearKnownPositiveRefCount();
switch (OldSeq) {
case S_Retain:
case S_CanRelease:
- if (OldSeq == S_Retain || ReleaseMetadata != 0)
- S.RRI.ReverseInsertPts.clear();
+ if (OldSeq == S_Retain || ReleaseMetadata != nullptr)
+ S.ClearReverseInsertPts();
// FALL THROUGH
case S_Use:
S.SetReleaseMetadata(ReleaseMetadata);
S.SetTailCallRelease(cast<CallInst>(Inst)->isTailCall());
- Releases[Inst] = S.RRI;
+ Releases[Inst] = S.GetRRInfo();
ANNOTATE_TOPDOWN(Inst, Arg, S.GetSeq(), S_None);
S.ClearSequenceProgress();
break;
}
break;
}
- case IC_AutoreleasepoolPop:
+ case ARCInstKind::AutoreleasepoolPop:
// Conservatively, clear MyStates for all known pointers.
MyStates.clearTopDownPointers();
return NestingDetected;
- case IC_AutoreleasepoolPush:
- case IC_None:
+ case ARCInstKind::AutoreleasepoolPush:
+ case ARCInstKind::None:
// These are irrelevant.
return NestingDetected;
default:
case S_Retain:
S.SetSeq(S_CanRelease);
ANNOTATE_TOPDOWN(Inst, Ptr, Seq, S_CanRelease);
- assert(S.RRI.ReverseInsertPts.empty());
- S.RRI.ReverseInsertPts.insert(Inst);
+ assert(!S.HasReverseInsertPts());
+ S.InsertReverseInsertPt(Inst);
// One call can't cause a transition from S_Retain to S_CanRelease
// and S_CanRelease to S_Use. If we've made the first transition,
while (SuccStack.back().second != SE) {
BasicBlock *SuccBB = *SuccStack.back().second++;
- if (Visited.insert(SuccBB)) {
+ if (Visited.insert(SuccBB).second) {
TerminatorInst *TI = cast<TerminatorInst>(&SuccBB->back());
SuccStack.push_back(std::make_pair(SuccBB, succ_iterator(TI)));
BBStates[CurrBB].addSucc(SuccBB);
BBState::edge_iterator PE = BBStates[PredStack.back().first].pred_end();
while (PredStack.back().second != PE) {
BasicBlock *BB = *PredStack.back().second++;
- if (Visited.insert(BB)) {
+ if (Visited.insert(BB).second) {
PredStack.push_back(std::make_pair(BB, BBStates[BB].pred_begin()));
goto reverse_dfs_next_succ;
}
}
// Visit the function both top-down and bottom-up.
-bool
-ObjCARCOpt::Visit(Function &F,
- DenseMap<const BasicBlock *, BBState> &BBStates,
- MapVector<Value *, RRInfo> &Retains,
- DenseMap<Value *, RRInfo> &Releases) {
+bool ObjCARCOpt::Visit(Function &F,
+ DenseMap<const BasicBlock *, BBState> &BBStates,
+ BlotMapVector<Value *, RRInfo> &Retains,
+ DenseMap<Value *, RRInfo> &Releases) {
// Use reverse-postorder traversals, because we magically know that loops
// will be well behaved, i.e. they won't repeatedly call retain on a single
}
/// Move the calls in RetainsToMove and ReleasesToMove.
-void ObjCARCOpt::MoveCalls(Value *Arg,
- RRInfo &RetainsToMove,
+void ObjCARCOpt::MoveCalls(Value *Arg, RRInfo &RetainsToMove,
RRInfo &ReleasesToMove,
- MapVector<Value *, RRInfo> &Retains,
+ BlotMapVector<Value *, RRInfo> &Retains,
DenseMap<Value *, RRInfo> &Releases,
SmallVectorImpl<Instruction *> &DeadInsts,
Module *M) {
DEBUG(dbgs() << "== ObjCARCOpt::MoveCalls ==\n");
// Insert the new retain and release calls.
- for (SmallPtrSet<Instruction *, 2>::const_iterator
- PI = ReleasesToMove.ReverseInsertPts.begin(),
- PE = ReleasesToMove.ReverseInsertPts.end(); PI != PE; ++PI) {
- Instruction *InsertPt = *PI;
+ for (Instruction *InsertPt : ReleasesToMove.ReverseInsertPts) {
Value *MyArg = ArgTy == ParamTy ? Arg :
new BitCastInst(Arg, ParamTy, "", InsertPt);
- CallInst *Call =
- CallInst::Create(getRetainCallee(M), MyArg, "", InsertPt);
+ Constant *Decl = EP.get(ARCRuntimeEntryPoints::EPT_Retain);
+ CallInst *Call = CallInst::Create(Decl, MyArg, "", InsertPt);
Call->setDoesNotThrow();
Call->setTailCall();
DEBUG(dbgs() << "Inserting new Retain: " << *Call << "\n"
"At insertion point: " << *InsertPt << "\n");
}
- for (SmallPtrSet<Instruction *, 2>::const_iterator
- PI = RetainsToMove.ReverseInsertPts.begin(),
- PE = RetainsToMove.ReverseInsertPts.end(); PI != PE; ++PI) {
- Instruction *InsertPt = *PI;
+ for (Instruction *InsertPt : RetainsToMove.ReverseInsertPts) {
Value *MyArg = ArgTy == ParamTy ? Arg :
new BitCastInst(Arg, ParamTy, "", InsertPt);
- CallInst *Call = CallInst::Create(getReleaseCallee(M), MyArg,
- "", InsertPt);
+ Constant *Decl = EP.get(ARCRuntimeEntryPoints::EPT_Release);
+ CallInst *Call = CallInst::Create(Decl, MyArg, "", InsertPt);
// Attach a clang.imprecise_release metadata tag, if appropriate.
if (MDNode *M = ReleasesToMove.ReleaseMetadata)
Call->setMetadata(ImpreciseReleaseMDKind, M);
}
// Delete the original retain and release calls.
- for (SmallPtrSet<Instruction *, 2>::const_iterator
- AI = RetainsToMove.Calls.begin(),
- AE = RetainsToMove.Calls.end(); AI != AE; ++AI) {
- Instruction *OrigRetain = *AI;
+ for (Instruction *OrigRetain : RetainsToMove.Calls) {
Retains.blot(OrigRetain);
DeadInsts.push_back(OrigRetain);
DEBUG(dbgs() << "Deleting retain: " << *OrigRetain << "\n");
}
- for (SmallPtrSet<Instruction *, 2>::const_iterator
- AI = ReleasesToMove.Calls.begin(),
- AE = ReleasesToMove.Calls.end(); AI != AE; ++AI) {
- Instruction *OrigRelease = *AI;
+ for (Instruction *OrigRelease : ReleasesToMove.Calls) {
Releases.erase(OrigRelease);
DeadInsts.push_back(OrigRelease);
DEBUG(dbgs() << "Deleting release: " << *OrigRelease << "\n");
}
-bool
-ObjCARCOpt::ConnectTDBUTraversals(DenseMap<const BasicBlock *, BBState>
- &BBStates,
- MapVector<Value *, RRInfo> &Retains,
- DenseMap<Value *, RRInfo> &Releases,
- Module *M,
- SmallVector<Instruction *, 4> &NewRetains,
- SmallVector<Instruction *, 4> &NewReleases,
- SmallVector<Instruction *, 8> &DeadInsts,
- RRInfo &RetainsToMove,
- RRInfo &ReleasesToMove,
- Value *Arg,
- bool KnownSafe,
- bool &AnyPairsCompletelyEliminated) {
+bool ObjCARCOpt::ConnectTDBUTraversals(
+ DenseMap<const BasicBlock *, BBState> &BBStates,
+ BlotMapVector<Value *, RRInfo> &Retains,
+ DenseMap<Value *, RRInfo> &Releases, Module *M,
+ SmallVectorImpl<Instruction *> &NewRetains,
+ SmallVectorImpl<Instruction *> &NewReleases,
+ SmallVectorImpl<Instruction *> &DeadInsts, RRInfo &RetainsToMove,
+ RRInfo &ReleasesToMove, Value *Arg, bool KnownSafe,
+ bool &AnyPairsCompletelyEliminated) {
// If a pair happens in a region where it is known that the reference count
// is already incremented, we can similarly ignore possible decrements unless
// we are dealing with a retainable object with multiple provenance sources.
for (SmallVectorImpl<Instruction *>::const_iterator
NI = NewRetains.begin(), NE = NewRetains.end(); NI != NE; ++NI) {
Instruction *NewRetain = *NI;
- MapVector<Value *, RRInfo>::const_iterator It = Retains.find(NewRetain);
+ BlotMapVector<Value *, RRInfo>::const_iterator It =
+ Retains.find(NewRetain);
assert(It != Retains.end());
const RRInfo &NewRetainRRI = It->second;
KnownSafeTD &= NewRetainRRI.KnownSafe;
MultipleOwners =
- MultipleOwners || MultiOwnersSet.count(GetObjCArg(NewRetain));
- for (SmallPtrSet<Instruction *, 2>::const_iterator
- LI = NewRetainRRI.Calls.begin(),
- LE = NewRetainRRI.Calls.end(); LI != LE; ++LI) {
- Instruction *NewRetainRelease = *LI;
+ MultipleOwners || MultiOwnersSet.count(GetArgRCIdentityRoot(NewRetain));
+ for (Instruction *NewRetainRelease : NewRetainRRI.Calls) {
DenseMap<Value *, RRInfo>::const_iterator Jt =
Releases.find(NewRetainRelease);
if (Jt == Releases.end())
return false;
const RRInfo &NewRetainReleaseRRI = Jt->second;
- assert(NewRetainReleaseRRI.Calls.count(NewRetain));
- if (ReleasesToMove.Calls.insert(NewRetainRelease)) {
+
+ // If the release does not have a reference to the retain as well,
+ // something happened which is unaccounted for. Do not do anything.
+ //
+ // This can happen if we catch an additive overflow during path count
+ // merging.
+ if (!NewRetainReleaseRRI.Calls.count(NewRetain))
+ return false;
+
+ if (ReleasesToMove.Calls.insert(NewRetainRelease).second) {
// If we overflow when we compute the path count, don't remove/move
// anything.
const BBState &NRRBBState = BBStates[NewRetainRelease->getParent()];
- unsigned PathCount;
+ unsigned PathCount = BBState::OverflowOccurredValue;
if (NRRBBState.GetAllPathCountWithOverflow(PathCount))
return false;
+ assert(PathCount != BBState::OverflowOccurredValue &&
+ "PathCount at this point can not be "
+ "OverflowOccurredValue.");
OldDelta -= PathCount;
// Merge the ReleaseMetadata and IsTailCallRelease values.
} else {
if (ReleasesToMove.ReleaseMetadata !=
NewRetainReleaseRRI.ReleaseMetadata)
- ReleasesToMove.ReleaseMetadata = 0;
+ ReleasesToMove.ReleaseMetadata = nullptr;
if (ReleasesToMove.IsTailCallRelease !=
NewRetainReleaseRRI.IsTailCallRelease)
ReleasesToMove.IsTailCallRelease = false;
// Collect the optimal insertion points.
if (!KnownSafe)
- for (SmallPtrSet<Instruction *, 2>::const_iterator
- RI = NewRetainReleaseRRI.ReverseInsertPts.begin(),
- RE = NewRetainReleaseRRI.ReverseInsertPts.end();
- RI != RE; ++RI) {
- Instruction *RIP = *RI;
- if (ReleasesToMove.ReverseInsertPts.insert(RIP)) {
+ for (Instruction *RIP : NewRetainReleaseRRI.ReverseInsertPts) {
+ if (ReleasesToMove.ReverseInsertPts.insert(RIP).second) {
// If we overflow when we compute the path count, don't
// remove/move anything.
const BBState &RIPBBState = BBStates[RIP->getParent()];
+ PathCount = BBState::OverflowOccurredValue;
if (RIPBBState.GetAllPathCountWithOverflow(PathCount))
return false;
+ assert(PathCount != BBState::OverflowOccurredValue &&
+ "PathCount at this point can not be "
+ "OverflowOccurredValue.");
NewDelta -= PathCount;
}
}
const RRInfo &NewReleaseRRI = It->second;
KnownSafeBU &= NewReleaseRRI.KnownSafe;
CFGHazardAfflicted |= NewReleaseRRI.CFGHazardAfflicted;
- for (SmallPtrSet<Instruction *, 2>::const_iterator
- LI = NewReleaseRRI.Calls.begin(),
- LE = NewReleaseRRI.Calls.end(); LI != LE; ++LI) {
- Instruction *NewReleaseRetain = *LI;
- MapVector<Value *, RRInfo>::const_iterator Jt =
- Retains.find(NewReleaseRetain);
+ for (Instruction *NewReleaseRetain : NewReleaseRRI.Calls) {
+ BlotMapVector<Value *, RRInfo>::const_iterator Jt =
+ Retains.find(NewReleaseRetain);
if (Jt == Retains.end())
return false;
const RRInfo &NewReleaseRetainRRI = Jt->second;
- assert(NewReleaseRetainRRI.Calls.count(NewRelease));
- if (RetainsToMove.Calls.insert(NewReleaseRetain)) {
+ // If the retain does not have a reference to the release as well,
+ // something happened which is unaccounted for. Do not do anything.
+ //
+ // This can happen if we catch an additive overflow during path count
+ // merging.
+ if (!NewReleaseRetainRRI.Calls.count(NewRelease))
+ return false;
+
+ if (RetainsToMove.Calls.insert(NewReleaseRetain).second) {
// If we overflow when we compute the path count, don't remove/move
// anything.
const BBState &NRRBBState = BBStates[NewReleaseRetain->getParent()];
- unsigned PathCount;
+ unsigned PathCount = BBState::OverflowOccurredValue;
if (NRRBBState.GetAllPathCountWithOverflow(PathCount))
return false;
+ assert(PathCount != BBState::OverflowOccurredValue &&
+ "PathCount at this point can not be "
+ "OverflowOccurredValue.");
OldDelta += PathCount;
OldCount += PathCount;
// Collect the optimal insertion points.
if (!KnownSafe)
- for (SmallPtrSet<Instruction *, 2>::const_iterator
- RI = NewReleaseRetainRRI.ReverseInsertPts.begin(),
- RE = NewReleaseRetainRRI.ReverseInsertPts.end();
- RI != RE; ++RI) {
- Instruction *RIP = *RI;
- if (RetainsToMove.ReverseInsertPts.insert(RIP)) {
+ for (Instruction *RIP : NewReleaseRetainRRI.ReverseInsertPts) {
+ if (RetainsToMove.ReverseInsertPts.insert(RIP).second) {
// If we overflow when we compute the path count, don't
// remove/move anything.
const BBState &RIPBBState = BBStates[RIP->getParent()];
+
+ PathCount = BBState::OverflowOccurredValue;
if (RIPBBState.GetAllPathCountWithOverflow(PathCount))
return false;
+ assert(PathCount != BBState::OverflowOccurredValue &&
+ "PathCount at this point can not be "
+ "OverflowOccurredValue.");
NewDelta += PathCount;
NewCount += PathCount;
}
/// Identify pairings between the retains and releases, and delete and/or move
/// them.
-bool
-ObjCARCOpt::PerformCodePlacement(DenseMap<const BasicBlock *, BBState>
- &BBStates,
- MapVector<Value *, RRInfo> &Retains,
- DenseMap<Value *, RRInfo> &Releases,
- Module *M) {
+bool ObjCARCOpt::PerformCodePlacement(
+ DenseMap<const BasicBlock *, BBState> &BBStates,
+ BlotMapVector<Value *, RRInfo> &Retains,
+ DenseMap<Value *, RRInfo> &Releases, Module *M) {
DEBUG(dbgs() << "\n== ObjCARCOpt::PerformCodePlacement ==\n");
bool AnyPairsCompletelyEliminated = false;
SmallVector<Instruction *, 8> DeadInsts;
// Visit each retain.
- for (MapVector<Value *, RRInfo>::const_iterator I = Retains.begin(),
- E = Retains.end(); I != E; ++I) {
+ for (BlotMapVector<Value *, RRInfo>::const_iterator I = Retains.begin(),
+ E = Retains.end();
+ I != E; ++I) {
Value *V = I->first;
if (!V) continue; // blotted
DEBUG(dbgs() << "Visiting: " << *Retain << "\n");
- Value *Arg = GetObjCArg(Retain);
+ Value *Arg = GetArgRCIdentityRoot(Retain);
// If the object being released is in static or stack storage, we know it's
// not being managed by ObjC reference counting, so we can delete pairs
if (const LoadInst *LI = dyn_cast<LoadInst>(Arg))
if (const GlobalVariable *GV =
dyn_cast<GlobalVariable>(
- StripPointerCastsAndObjCCalls(LI->getPointerOperand())))
+ GetRCIdentityRoot(LI->getPointerOperand())))
if (GV->isConstant())
KnownSafe = true;
DEBUG(dbgs() << "Visiting: " << *Inst << "\n");
- InstructionClass Class = GetBasicInstructionClass(Inst);
- if (Class != IC_LoadWeak && Class != IC_LoadWeakRetained)
+ ARCInstKind Class = GetBasicARCInstKind(Inst);
+ if (Class != ARCInstKind::LoadWeak &&
+ Class != ARCInstKind::LoadWeakRetained)
continue;
// Delete objc_loadWeak calls with no users.
- if (Class == IC_LoadWeak && Inst->use_empty()) {
+ if (Class == ARCInstKind::LoadWeak && Inst->use_empty()) {
Inst->eraseFromParent();
continue;
}
// within the same block. Theoretically, we could do memdep-style non-local
// analysis too, but that would want caching. A better approach would be to
// use the technique that EarlyCSE uses.
- inst_iterator Current = llvm::prior(I);
+ inst_iterator Current = std::prev(I);
BasicBlock *CurrentBB = Current.getBasicBlockIterator();
for (BasicBlock::iterator B = CurrentBB->begin(),
J = Current.getInstructionIterator();
J != B; --J) {
- Instruction *EarlierInst = &*llvm::prior(J);
- InstructionClass EarlierClass = GetInstructionClass(EarlierInst);
+ Instruction *EarlierInst = &*std::prev(J);
+ ARCInstKind EarlierClass = GetARCInstKind(EarlierInst);
switch (EarlierClass) {
- case IC_LoadWeak:
- case IC_LoadWeakRetained: {
+ case ARCInstKind::LoadWeak:
+ case ARCInstKind::LoadWeakRetained: {
// If this is loading from the same pointer, replace this load's value
// with that one.
CallInst *Call = cast<CallInst>(Inst);
case AliasAnalysis::MustAlias:
Changed = true;
// If the load has a builtin retain, insert a plain retain for it.
- if (Class == IC_LoadWeakRetained) {
- CallInst *CI =
- CallInst::Create(getRetainCallee(F.getParent()), EarlierCall,
- "", Call);
+ if (Class == ARCInstKind::LoadWeakRetained) {
+ Constant *Decl = EP.get(ARCRuntimeEntryPoints::EPT_Retain);
+ CallInst *CI = CallInst::Create(Decl, EarlierCall, "", Call);
CI->setTailCall();
}
// Zap the fully redundant load.
}
break;
}
- case IC_StoreWeak:
- case IC_InitWeak: {
+ case ARCInstKind::StoreWeak:
+ case ARCInstKind::InitWeak: {
// If this is storing to the same pointer and has the same size etc.
// replace this load's value with the stored value.
CallInst *Call = cast<CallInst>(Inst);
case AliasAnalysis::MustAlias:
Changed = true;
// If the load has a builtin retain, insert a plain retain for it.
- if (Class == IC_LoadWeakRetained) {
- CallInst *CI =
- CallInst::Create(getRetainCallee(F.getParent()), EarlierCall,
- "", Call);
+ if (Class == ARCInstKind::LoadWeakRetained) {
+ Constant *Decl = EP.get(ARCRuntimeEntryPoints::EPT_Retain);
+ CallInst *CI = CallInst::Create(Decl, EarlierCall, "", Call);
CI->setTailCall();
}
// Zap the fully redundant load.
}
break;
}
- case IC_MoveWeak:
- case IC_CopyWeak:
+ case ARCInstKind::MoveWeak:
+ case ARCInstKind::CopyWeak:
// TOOD: Grab the copied value.
goto clobbered;
- case IC_AutoreleasepoolPush:
- case IC_None:
- case IC_IntrinsicUser:
- case IC_User:
+ case ARCInstKind::AutoreleasepoolPush:
+ case ARCInstKind::None:
+ case ARCInstKind::IntrinsicUser:
+ case ARCInstKind::User:
// Weak pointers are only modified through the weak entry points
// (and arbitrary calls, which could call the weak entry points).
break;
// the alloca and all its users can be zapped.
for (inst_iterator I = inst_begin(&F), E = inst_end(&F); I != E; ) {
Instruction *Inst = &*I++;
- InstructionClass Class = GetBasicInstructionClass(Inst);
- if (Class != IC_DestroyWeak)
+ ARCInstKind Class = GetBasicARCInstKind(Inst);
+ if (Class != ARCInstKind::DestroyWeak)
continue;
CallInst *Call = cast<CallInst>(Inst);
Value *Arg = Call->getArgOperand(0);
if (AllocaInst *Alloca = dyn_cast<AllocaInst>(Arg)) {
- for (Value::use_iterator UI = Alloca->use_begin(),
- UE = Alloca->use_end(); UI != UE; ++UI) {
- const Instruction *UserInst = cast<Instruction>(*UI);
- switch (GetBasicInstructionClass(UserInst)) {
- case IC_InitWeak:
- case IC_StoreWeak:
- case IC_DestroyWeak:
+ for (User *U : Alloca->users()) {
+ const Instruction *UserInst = cast<Instruction>(U);
+ switch (GetBasicARCInstKind(UserInst)) {
+ case ARCInstKind::InitWeak:
+ case ARCInstKind::StoreWeak:
+ case ARCInstKind::DestroyWeak:
continue;
default:
goto done;
}
}
Changed = true;
- for (Value::use_iterator UI = Alloca->use_begin(),
- UE = Alloca->use_end(); UI != UE; ) {
+ for (auto UI = Alloca->user_begin(), UE = Alloca->user_end(); UI != UE;) {
CallInst *UserInst = cast<CallInst>(*UI++);
- switch (GetBasicInstructionClass(UserInst)) {
- case IC_InitWeak:
- case IC_StoreWeak:
+ switch (GetBasicARCInstKind(UserInst)) {
+ case ARCInstKind::InitWeak:
+ case ARCInstKind::StoreWeak:
// These functions return their second argument.
UserInst->replaceAllUsesWith(UserInst->getArgOperand(1));
break;
- case IC_DestroyWeak:
+ case ARCInstKind::DestroyWeak:
// No return value.
break;
default:
// map stays valid when we get around to rewriting code and calls get
// replaced by arguments.
DenseMap<Value *, RRInfo> Releases;
- MapVector<Value *, RRInfo> Retains;
+ BlotMapVector<Value *, RRInfo> Retains;
// This is used during the traversal of the function to track the
// states for each identified object at each block.
/// shared pointer argument. Note that Retain need not be in BB.
static bool
HasSafePathToPredecessorCall(const Value *Arg, Instruction *Retain,
- SmallPtrSet<Instruction *, 4> &DepInsts,
- SmallPtrSet<const BasicBlock *, 4> &Visited,
+ SmallPtrSetImpl<Instruction *> &DepInsts,
+ SmallPtrSetImpl<const BasicBlock *> &Visited,
ProvenanceAnalysis &PA) {
FindDependencies(CanChangeRetainCount, Arg, Retain->getParent(), Retain,
DepInsts, Visited, PA);
if (DepInsts.size() != 1)
return false;
- CallInst *Call =
- dyn_cast_or_null<CallInst>(*DepInsts.begin());
+ auto *Call = dyn_cast_or_null<CallInst>(*DepInsts.begin());
// Check that the pointer is the return value of the call.
if (!Call || Arg != Call)
return false;
// Check that the call is a regular call.
- InstructionClass Class = GetBasicInstructionClass(Call);
- if (Class != IC_CallOrUser && Class != IC_Call)
+ ARCInstKind Class = GetBasicARCInstKind(Call);
+ if (Class != ARCInstKind::CallOrUser && Class != ARCInstKind::Call)
return false;
return true;
static CallInst *
FindPredecessorRetainWithSafePath(const Value *Arg, BasicBlock *BB,
Instruction *Autorelease,
- SmallPtrSet<Instruction *, 4> &DepInsts,
- SmallPtrSet<const BasicBlock *, 4> &Visited,
+ SmallPtrSetImpl<Instruction *> &DepInsts,
+ SmallPtrSetImpl<const BasicBlock *> &Visited,
ProvenanceAnalysis &PA) {
FindDependencies(CanChangeRetainCount, Arg,
BB, Autorelease, DepInsts, Visited, PA);
if (DepInsts.size() != 1)
- return 0;
+ return nullptr;
- CallInst *Retain =
- dyn_cast_or_null<CallInst>(*DepInsts.begin());
+ auto *Retain = dyn_cast_or_null<CallInst>(*DepInsts.begin());
// Check that we found a retain with the same argument.
- if (!Retain ||
- !IsRetain(GetBasicInstructionClass(Retain)) ||
- GetObjCArg(Retain) != Arg) {
- return 0;
+ if (!Retain || !IsRetain(GetBasicARCInstKind(Retain)) ||
+ GetArgRCIdentityRoot(Retain) != Arg) {
+ return nullptr;
}
return Retain;
static CallInst *
FindPredecessorAutoreleaseWithSafePath(const Value *Arg, BasicBlock *BB,
ReturnInst *Ret,
- SmallPtrSet<Instruction *, 4> &DepInsts,
- SmallPtrSet<const BasicBlock *, 4> &V,
+ SmallPtrSetImpl<Instruction *> &DepInsts,
+ SmallPtrSetImpl<const BasicBlock *> &V,
ProvenanceAnalysis &PA) {
FindDependencies(NeedsPositiveRetainCount, Arg,
BB, Ret, DepInsts, V, PA);
if (DepInsts.size() != 1)
- return 0;
+ return nullptr;
- CallInst *Autorelease =
- dyn_cast_or_null<CallInst>(*DepInsts.begin());
+ auto *Autorelease = dyn_cast_or_null<CallInst>(*DepInsts.begin());
if (!Autorelease)
- return 0;
- InstructionClass AutoreleaseClass = GetBasicInstructionClass(Autorelease);
+ return nullptr;
+ ARCInstKind AutoreleaseClass = GetBasicARCInstKind(Autorelease);
if (!IsAutorelease(AutoreleaseClass))
- return 0;
- if (GetObjCArg(Autorelease) != Arg)
- return 0;
+ return nullptr;
+ if (GetArgRCIdentityRoot(Autorelease) != Arg)
+ return nullptr;
return Autorelease;
}
if (!Ret)
continue;
- const Value *Arg = StripPointerCastsAndObjCCalls(Ret->getOperand(0));
+ const Value *Arg = GetRCIdentityRoot(Ret->getOperand(0));
// Look for an ``autorelease'' instruction that is a predecessor of Ret and
// dependent on Arg such that there are no instructions dependent on Arg
for (inst_iterator I = inst_begin(&F), E = inst_end(&F); I != E; ) {
Instruction *Inst = &*I++;
- switch (GetBasicInstructionClass(Inst)) {
+ switch (GetBasicARCInstKind(Inst)) {
default:
break;
- case IC_Retain:
+ case ARCInstKind::Retain:
++NumRetains;
break;
- case IC_Release:
+ case ARCInstKind::Release:
++NumReleases;
break;
}
// they are not, because they return their argument value. And objc_release
// calls finalizers which can have arbitrary side effects.
- // These are initialized lazily.
- AutoreleaseRVCallee = 0;
- ReleaseCallee = 0;
- RetainCallee = 0;
- RetainBlockCallee = 0;
- AutoreleaseCallee = 0;
+ // Initialize our runtime entry point cache.
+ EP.Initialize(&M);
return false;
}
OptimizeIndividualCalls(F);
// Optimizations for weak pointers.
- if (UsedInThisFunction & ((1 << IC_LoadWeak) |
- (1 << IC_LoadWeakRetained) |
- (1 << IC_StoreWeak) |
- (1 << IC_InitWeak) |
- (1 << IC_CopyWeak) |
- (1 << IC_MoveWeak) |
- (1 << IC_DestroyWeak)))
+ if (UsedInThisFunction & ((1 << unsigned(ARCInstKind::LoadWeak)) |
+ (1 << unsigned(ARCInstKind::LoadWeakRetained)) |
+ (1 << unsigned(ARCInstKind::StoreWeak)) |
+ (1 << unsigned(ARCInstKind::InitWeak)) |
+ (1 << unsigned(ARCInstKind::CopyWeak)) |
+ (1 << unsigned(ARCInstKind::MoveWeak)) |
+ (1 << unsigned(ARCInstKind::DestroyWeak))))
OptimizeWeakCalls(F);
// Optimizations for retain+release pairs.
- if (UsedInThisFunction & ((1 << IC_Retain) |
- (1 << IC_RetainRV) |
- (1 << IC_RetainBlock)))
- if (UsedInThisFunction & (1 << IC_Release))
+ if (UsedInThisFunction & ((1 << unsigned(ARCInstKind::Retain)) |
+ (1 << unsigned(ARCInstKind::RetainRV)) |
+ (1 << unsigned(ARCInstKind::RetainBlock))))
+ if (UsedInThisFunction & (1 << unsigned(ARCInstKind::Release)))
// Run OptimizeSequences until it either stops making changes or
// no retain+release pair nesting is detected.
while (OptimizeSequences(F)) {}
// Optimizations if objc_autorelease is used.
- if (UsedInThisFunction & ((1 << IC_Autorelease) |
- (1 << IC_AutoreleaseRV)))
+ if (UsedInThisFunction & ((1 << unsigned(ARCInstKind::Autorelease)) |
+ (1 << unsigned(ARCInstKind::AutoreleaseRV))))
OptimizeReturns(F);
// Gather statistics after optimization.
projects / oota-llvm.git / blobdiff