forked from OSchip/llvm-project
75 lines
3.0 KiB
C++
75 lines
3.0 KiB
C++
//===- ObjCARCAliasAnalysis.h - ObjC ARC Optimization -*- mode: c++ -*-----===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
/// \file
|
|
/// This file declares a simple ARC-aware AliasAnalysis using special knowledge
|
|
/// of Objective C to enhance other optimization passes which rely on the Alias
|
|
/// Analysis infrastructure.
|
|
///
|
|
/// WARNING: This file knows about certain library functions. It recognizes them
|
|
/// by name, and hardwires knowledge of their semantics.
|
|
///
|
|
/// WARNING: This file knows about how certain Objective-C library functions are
|
|
/// used. Naive LLVM IR transformations which would otherwise be
|
|
/// behavior-preserving may break these assumptions.
|
|
///
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_TRANSFORMS_OBJCARC_OBJCARCALIASANALYSIS_H
|
|
#define LLVM_TRANSFORMS_OBJCARC_OBJCARCALIASANALYSIS_H
|
|
|
|
#include "llvm/Analysis/AliasAnalysis.h"
|
|
#include "llvm/Pass.h"
|
|
|
|
namespace llvm {
|
|
namespace objcarc {
|
|
|
|
/// \brief This is a simple alias analysis implementation that uses knowledge
|
|
/// of ARC constructs to answer queries.
|
|
///
|
|
/// TODO: This class could be generalized to know about other ObjC-specific
|
|
/// tricks. Such as knowing that ivars in the non-fragile ABI are non-aliasing
|
|
/// even though their offsets are dynamic.
|
|
class ObjCARCAliasAnalysis : public ImmutablePass,
|
|
public AliasAnalysis {
|
|
public:
|
|
static char ID; // Class identification, replacement for typeinfo
|
|
ObjCARCAliasAnalysis() : ImmutablePass(ID) {
|
|
initializeObjCARCAliasAnalysisPass(*PassRegistry::getPassRegistry());
|
|
}
|
|
|
|
private:
|
|
virtual void initializePass() {
|
|
InitializeAliasAnalysis(this);
|
|
}
|
|
|
|
/// This method is used when a pass implements an analysis interface through
|
|
/// multiple inheritance. If needed, it should override this to adjust the
|
|
/// this pointer as needed for the specified pass info.
|
|
virtual void *getAdjustedAnalysisPointer(const void *PI) {
|
|
if (PI == &AliasAnalysis::ID)
|
|
return static_cast<AliasAnalysis *>(this);
|
|
return this;
|
|
}
|
|
|
|
virtual void getAnalysisUsage(AnalysisUsage &AU) const;
|
|
virtual AliasResult alias(const Location &LocA, const Location &LocB);
|
|
virtual bool pointsToConstantMemory(const Location &Loc, bool OrLocal);
|
|
virtual ModRefBehavior getModRefBehavior(ImmutableCallSite CS);
|
|
virtual ModRefBehavior getModRefBehavior(const Function *F);
|
|
virtual ModRefResult getModRefInfo(ImmutableCallSite CS,
|
|
const Location &Loc);
|
|
virtual ModRefResult getModRefInfo(ImmutableCallSite CS1,
|
|
ImmutableCallSite CS2);
|
|
};
|
|
|
|
} // namespace objcarc
|
|
} // namespace llvm
|
|
|
|
#endif // LLVM_TRANSFORMS_OBJCARC_OBJCARCALIASANALYSIS_H
|