llvm/llvm/lib/Transforms/ObjCARC/ProvenanceAnalysis.cpp

//===- ProvenanceAnalysis.cpp - ObjC ARC Optimization ---------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
/// \file
///
/// This file defines a special form of Alias Analysis called ``Provenance
/// Analysis''. The word ``provenance'' refers to the history of the ownership
/// of an object. Thus ``Provenance Analysis'' is an analysis which attempts to
/// use various techniques to determine if locally
///
/// 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.
//
//===----------------------------------------------------------------------===//

#include "ProvenanceAnalysis.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/ObjCARCAnalysisUtils.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Use.h"
#include "llvm/IR/User.h"
#include "llvm/IR/Value.h"
#include "llvm/Support/Casting.h"
#include <utility>

usingnamespacellvm;
usingnamespacellvm::objcarc;

bool ProvenanceAnalysis::relatedSelect(const SelectInst *A,
                                       const Value *B) { … }

bool ProvenanceAnalysis::relatedPHI(const PHINode *A,
                                    const Value *B) { … }

/// Test if the value of P, or any value covered by its provenance, is ever
/// stored within the function (not counting callees).
static bool IsStoredObjCPointer(const Value *P) { … }

bool ProvenanceAnalysis::relatedCheck(const Value *A, const Value *B) { … }

bool ProvenanceAnalysis::related(const Value *A, const Value *B) { … }