#include "ObjCARCAliasAnalysis.h"
#include "ProvenanceAnalysis.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"
/// A flag indicating whether this optimization pass should run.
bool Run;
+ /// This set contains references to objc_autorelease calls that at one point
+ /// in time were objc_autoreleaseRV calls. Thus we can disambiguate
+ /// in between objc_autorelease that were inserted from the frontend (which
+ /// we must be very conservative with) and those as a result of strength
+ /// reducing objc_autoreleaseRV calls (which are more flexible).
+ DenseSet<Instruction *> ImpreciseAutoreleaseSet;
+
/// 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.
bool IsRetainBlockOptimizable(const Instruction *Inst);
+ /// Erase an instruction.
+ ///
+ /// This is included separately from the EraseInstruction in ObjCARC.h
+ /// (which this uses internally) in order to make sure that state is cleaned
+ /// up. Currently this just means attempting to remove said instruction from
+ /// ImpreciseAutoreleaseSet if it is an autorelease instruction. This will
+ /// prevent bugs of the sort where we erase an instruction and forget to
+ /// remove any associated state.
+ ///
+ /// TODO: Maybe remove this, the ImpreciseAutoreleaseSet, the
+ /// MetadataKind/Callee variables into a separate class.
+ void EraseInstruction(Instruction *Inst) {
+ // If Inst is an autorelease instruction, erase it from
+ // ImpreciseAutoreleaseSet if it is contained there in.
+ if (GetBasicInstructionClass(Inst) == IC_Autorelease) {
+ ImpreciseAutoreleaseSet.erase(Inst);
+ }
+ // Invoke the normal EraseInstruction.
+ llvm::objcarc::EraseInstruction(Inst);
+ }
+
void OptimizeRetainCall(Function &F, Instruction *Retain);
bool OptimizeRetainRVCall(Function &F, Instruction *RetainRV);
void OptimizeAutoreleaseRVCall(Function &F, Instruction *AutoreleaseRV,
AutoreleaseRVCI->setTailCall(false); // Never tail call objc_autorelease.
Class = IC_Autorelease;
+ // Stash the given instruction in the ImpreciseAutoreleaseSet so we can check
+ // later on that this instruction was an autoreleaseRV instruction that was
+ // converted to an autorelease instead of an autorelease inserted by the
+ // frontend (which we can not touch).
+ ImpreciseAutoreleaseSet.insert(AutoreleaseRVCI);
+
DEBUG(dbgs() << "New: " << *AutoreleaseRV << "\n");
}
DEBUG(dbgs() << "\n");
+ ImpreciseAutoreleaseSet.clear();
+
return Changed;
}
void ObjCARCOpt::releaseMemory() {
PA.clear();
+ ImpreciseAutoreleaseSet.clear();
}
/// @}