forked from OSchip/llvm-project
3831 lines
133 KiB
C++
3831 lines
133 KiB
C++
//==-- RetainCountChecker.cpp - Checks for leaks and other issues -*- C++ -*--//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file defines the methods for RetainCountChecker, which implements
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// a reference count checker for Core Foundation and Cocoa on (Mac OS X).
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//
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//===----------------------------------------------------------------------===//
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#include "ClangSACheckers.h"
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#include "AllocationDiagnostics.h"
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#include "SelectorExtras.h"
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#include "clang/AST/Attr.h"
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#include "clang/AST/DeclCXX.h"
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#include "clang/AST/DeclObjC.h"
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#include "clang/AST/ParentMap.h"
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#include "clang/Analysis/DomainSpecific/CocoaConventions.h"
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#include "clang/Basic/LangOptions.h"
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#include "clang/Basic/SourceManager.h"
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#include "clang/StaticAnalyzer/Checkers/ObjCRetainCount.h"
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#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
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#include "clang/StaticAnalyzer/Core/BugReporter/PathDiagnostic.h"
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#include "clang/StaticAnalyzer/Core/Checker.h"
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#include "clang/StaticAnalyzer/Core/CheckerManager.h"
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#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
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#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
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#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h"
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#include "clang/StaticAnalyzer/Core/PathSensitive/SymbolManager.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/FoldingSet.h"
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#include "llvm/ADT/ImmutableList.h"
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#include "llvm/ADT/ImmutableMap.h"
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#include "llvm/ADT/STLExtras.h"
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#include "llvm/ADT/SmallString.h"
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#include "llvm/ADT/StringExtras.h"
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#include <cstdarg>
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using namespace clang;
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using namespace ento;
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using namespace objc_retain;
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using llvm::StrInStrNoCase;
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//===----------------------------------------------------------------------===//
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// Adapters for FoldingSet.
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//===----------------------------------------------------------------------===//
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namespace llvm {
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template <> struct FoldingSetTrait<ArgEffect> {
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static inline void Profile(const ArgEffect X, FoldingSetNodeID &ID) {
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ID.AddInteger((unsigned) X);
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}
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};
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template <> struct FoldingSetTrait<RetEffect> {
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static inline void Profile(const RetEffect &X, FoldingSetNodeID &ID) {
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ID.AddInteger((unsigned) X.getKind());
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ID.AddInteger((unsigned) X.getObjKind());
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}
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};
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} // end llvm namespace
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//===----------------------------------------------------------------------===//
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// Reference-counting logic (typestate + counts).
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//===----------------------------------------------------------------------===//
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/// ArgEffects summarizes the effects of a function/method call on all of
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/// its arguments.
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typedef llvm::ImmutableMap<unsigned,ArgEffect> ArgEffects;
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namespace {
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class RefVal {
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public:
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enum Kind {
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Owned = 0, // Owning reference.
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NotOwned, // Reference is not owned by still valid (not freed).
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Released, // Object has been released.
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ReturnedOwned, // Returned object passes ownership to caller.
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ReturnedNotOwned, // Return object does not pass ownership to caller.
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ERROR_START,
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ErrorDeallocNotOwned, // -dealloc called on non-owned object.
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ErrorDeallocGC, // Calling -dealloc with GC enabled.
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ErrorUseAfterRelease, // Object used after released.
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ErrorReleaseNotOwned, // Release of an object that was not owned.
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ERROR_LEAK_START,
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ErrorLeak, // A memory leak due to excessive reference counts.
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ErrorLeakReturned, // A memory leak due to the returning method not having
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// the correct naming conventions.
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ErrorGCLeakReturned,
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ErrorOverAutorelease,
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ErrorReturnedNotOwned
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};
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private:
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/// The number of outstanding retains.
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unsigned Cnt;
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/// The number of outstanding autoreleases.
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unsigned ACnt;
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/// The (static) type of the object at the time we started tracking it.
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QualType T;
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/// The current state of the object.
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///
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/// See the RefVal::Kind enum for possible values.
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unsigned RawKind : 5;
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/// The kind of object being tracked (CF or ObjC), if known.
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///
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/// See the RetEffect::ObjKind enum for possible values.
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unsigned RawObjectKind : 2;
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/// True if the current state and/or retain count may turn out to not be the
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/// best possible approximation of the reference counting state.
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///
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/// If true, the checker may decide to throw away ("override") this state
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/// in favor of something else when it sees the object being used in new ways.
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///
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/// This setting should not be propagated to state derived from this state.
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/// Once we start deriving new states, it would be inconsistent to override
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/// them.
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unsigned IsOverridable : 1;
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RefVal(Kind k, RetEffect::ObjKind o, unsigned cnt, unsigned acnt, QualType t,
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bool Overridable = false)
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: Cnt(cnt), ACnt(acnt), T(t), RawKind(static_cast<unsigned>(k)),
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RawObjectKind(static_cast<unsigned>(o)), IsOverridable(Overridable) {
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assert(getKind() == k && "not enough bits for the kind");
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assert(getObjKind() == o && "not enough bits for the object kind");
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}
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public:
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Kind getKind() const { return static_cast<Kind>(RawKind); }
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RetEffect::ObjKind getObjKind() const {
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return static_cast<RetEffect::ObjKind>(RawObjectKind);
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}
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unsigned getCount() const { return Cnt; }
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unsigned getAutoreleaseCount() const { return ACnt; }
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unsigned getCombinedCounts() const { return Cnt + ACnt; }
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void clearCounts() {
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Cnt = 0;
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ACnt = 0;
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IsOverridable = false;
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}
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void setCount(unsigned i) {
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Cnt = i;
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IsOverridable = false;
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}
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void setAutoreleaseCount(unsigned i) {
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ACnt = i;
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IsOverridable = false;
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}
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QualType getType() const { return T; }
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bool isOverridable() const { return IsOverridable; }
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bool isOwned() const {
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return getKind() == Owned;
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}
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bool isNotOwned() const {
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return getKind() == NotOwned;
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}
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bool isReturnedOwned() const {
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return getKind() == ReturnedOwned;
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}
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bool isReturnedNotOwned() const {
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return getKind() == ReturnedNotOwned;
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}
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/// Create a state for an object whose lifetime is the responsibility of the
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/// current function, at least partially.
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///
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/// Most commonly, this is an owned object with a retain count of +1.
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static RefVal makeOwned(RetEffect::ObjKind o, QualType t,
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unsigned Count = 1) {
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return RefVal(Owned, o, Count, 0, t);
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}
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/// Create a state for an object whose lifetime is not the responsibility of
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/// the current function.
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///
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/// Most commonly, this is an unowned object with a retain count of +0.
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static RefVal makeNotOwned(RetEffect::ObjKind o, QualType t,
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unsigned Count = 0) {
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return RefVal(NotOwned, o, Count, 0, t);
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}
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/// Create an "overridable" state for an unowned object at +0.
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///
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/// An overridable state is one that provides a good approximation of the
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/// reference counting state now, but which may be discarded later if the
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/// checker sees the object being used in new ways.
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static RefVal makeOverridableNotOwned(RetEffect::ObjKind o, QualType t) {
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return RefVal(NotOwned, o, 0, 0, t, /*Overridable=*/true);
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}
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RefVal operator-(size_t i) const {
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return RefVal(getKind(), getObjKind(), getCount() - i,
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getAutoreleaseCount(), getType());
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}
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RefVal operator+(size_t i) const {
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return RefVal(getKind(), getObjKind(), getCount() + i,
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getAutoreleaseCount(), getType());
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}
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RefVal operator^(Kind k) const {
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return RefVal(k, getObjKind(), getCount(), getAutoreleaseCount(),
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getType());
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}
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RefVal autorelease() const {
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return RefVal(getKind(), getObjKind(), getCount(), getAutoreleaseCount()+1,
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getType());
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}
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// Comparison, profiling, and pretty-printing.
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bool hasSameState(const RefVal &X) const {
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return getKind() == X.getKind() && Cnt == X.Cnt && ACnt == X.ACnt;
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}
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bool operator==(const RefVal& X) const {
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return T == X.T && hasSameState(X) && getObjKind() == X.getObjKind() &&
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IsOverridable == X.IsOverridable;
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}
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void Profile(llvm::FoldingSetNodeID& ID) const {
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ID.Add(T);
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ID.AddInteger(RawKind);
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ID.AddInteger(Cnt);
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ID.AddInteger(ACnt);
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ID.AddInteger(RawObjectKind);
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ID.AddBoolean(IsOverridable);
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}
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void print(raw_ostream &Out) const;
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};
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void RefVal::print(raw_ostream &Out) const {
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if (!T.isNull())
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Out << "Tracked " << T.getAsString() << '/';
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if (isOverridable())
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Out << "(overridable) ";
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switch (getKind()) {
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default: llvm_unreachable("Invalid RefVal kind");
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case Owned: {
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Out << "Owned";
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unsigned cnt = getCount();
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if (cnt) Out << " (+ " << cnt << ")";
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break;
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}
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case NotOwned: {
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Out << "NotOwned";
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unsigned cnt = getCount();
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if (cnt) Out << " (+ " << cnt << ")";
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break;
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}
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case ReturnedOwned: {
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Out << "ReturnedOwned";
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unsigned cnt = getCount();
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if (cnt) Out << " (+ " << cnt << ")";
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break;
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}
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case ReturnedNotOwned: {
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Out << "ReturnedNotOwned";
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unsigned cnt = getCount();
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if (cnt) Out << " (+ " << cnt << ")";
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break;
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}
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case Released:
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Out << "Released";
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break;
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case ErrorDeallocGC:
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Out << "-dealloc (GC)";
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break;
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case ErrorDeallocNotOwned:
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Out << "-dealloc (not-owned)";
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break;
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case ErrorLeak:
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Out << "Leaked";
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break;
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case ErrorLeakReturned:
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Out << "Leaked (Bad naming)";
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break;
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case ErrorGCLeakReturned:
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Out << "Leaked (GC-ed at return)";
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break;
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case ErrorUseAfterRelease:
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Out << "Use-After-Release [ERROR]";
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break;
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case ErrorReleaseNotOwned:
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Out << "Release of Not-Owned [ERROR]";
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break;
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case RefVal::ErrorOverAutorelease:
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Out << "Over-autoreleased";
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break;
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case RefVal::ErrorReturnedNotOwned:
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Out << "Non-owned object returned instead of owned";
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break;
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}
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if (ACnt) {
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Out << " [ARC +" << ACnt << ']';
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}
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}
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} //end anonymous namespace
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//===----------------------------------------------------------------------===//
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// RefBindings - State used to track object reference counts.
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//===----------------------------------------------------------------------===//
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REGISTER_MAP_WITH_PROGRAMSTATE(RefBindings, SymbolRef, RefVal)
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static inline const RefVal *getRefBinding(ProgramStateRef State,
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SymbolRef Sym) {
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return State->get<RefBindings>(Sym);
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}
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static inline ProgramStateRef setRefBinding(ProgramStateRef State,
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SymbolRef Sym, RefVal Val) {
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return State->set<RefBindings>(Sym, Val);
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}
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static ProgramStateRef removeRefBinding(ProgramStateRef State, SymbolRef Sym) {
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return State->remove<RefBindings>(Sym);
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}
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//===----------------------------------------------------------------------===//
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// Function/Method behavior summaries.
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//===----------------------------------------------------------------------===//
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namespace {
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class RetainSummary {
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/// Args - a map of (index, ArgEffect) pairs, where index
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/// specifies the argument (starting from 0). This can be sparsely
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/// populated; arguments with no entry in Args use 'DefaultArgEffect'.
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ArgEffects Args;
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/// DefaultArgEffect - The default ArgEffect to apply to arguments that
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/// do not have an entry in Args.
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ArgEffect DefaultArgEffect;
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/// Receiver - If this summary applies to an Objective-C message expression,
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/// this is the effect applied to the state of the receiver.
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ArgEffect Receiver;
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/// Ret - The effect on the return value. Used to indicate if the
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/// function/method call returns a new tracked symbol.
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RetEffect Ret;
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public:
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RetainSummary(ArgEffects A, RetEffect R, ArgEffect defaultEff,
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ArgEffect ReceiverEff)
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: Args(A), DefaultArgEffect(defaultEff), Receiver(ReceiverEff), Ret(R) {}
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/// getArg - Return the argument effect on the argument specified by
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/// idx (starting from 0).
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ArgEffect getArg(unsigned idx) const {
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if (const ArgEffect *AE = Args.lookup(idx))
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return *AE;
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return DefaultArgEffect;
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}
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void addArg(ArgEffects::Factory &af, unsigned idx, ArgEffect e) {
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Args = af.add(Args, idx, e);
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}
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/// setDefaultArgEffect - Set the default argument effect.
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void setDefaultArgEffect(ArgEffect E) {
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DefaultArgEffect = E;
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}
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/// getRetEffect - Returns the effect on the return value of the call.
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RetEffect getRetEffect() const { return Ret; }
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/// setRetEffect - Set the effect of the return value of the call.
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void setRetEffect(RetEffect E) { Ret = E; }
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/// Sets the effect on the receiver of the message.
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void setReceiverEffect(ArgEffect e) { Receiver = e; }
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/// getReceiverEffect - Returns the effect on the receiver of the call.
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/// This is only meaningful if the summary applies to an ObjCMessageExpr*.
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ArgEffect getReceiverEffect() const { return Receiver; }
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/// Test if two retain summaries are identical. Note that merely equivalent
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/// summaries are not necessarily identical (for example, if an explicit
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/// argument effect matches the default effect).
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bool operator==(const RetainSummary &Other) const {
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return Args == Other.Args && DefaultArgEffect == Other.DefaultArgEffect &&
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Receiver == Other.Receiver && Ret == Other.Ret;
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}
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/// Profile this summary for inclusion in a FoldingSet.
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void Profile(llvm::FoldingSetNodeID& ID) const {
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ID.Add(Args);
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ID.Add(DefaultArgEffect);
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ID.Add(Receiver);
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ID.Add(Ret);
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}
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/// A retain summary is simple if it has no ArgEffects other than the default.
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bool isSimple() const {
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return Args.isEmpty();
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}
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private:
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ArgEffects getArgEffects() const { return Args; }
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ArgEffect getDefaultArgEffect() const { return DefaultArgEffect; }
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friend class RetainSummaryManager;
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};
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} // end anonymous namespace
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//===----------------------------------------------------------------------===//
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// Data structures for constructing summaries.
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//===----------------------------------------------------------------------===//
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namespace {
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class ObjCSummaryKey {
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IdentifierInfo* II;
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Selector S;
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public:
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ObjCSummaryKey(IdentifierInfo* ii, Selector s)
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: II(ii), S(s) {}
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ObjCSummaryKey(const ObjCInterfaceDecl *d, Selector s)
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: II(d ? d->getIdentifier() : 0), S(s) {}
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ObjCSummaryKey(Selector s)
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: II(0), S(s) {}
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IdentifierInfo *getIdentifier() const { return II; }
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Selector getSelector() const { return S; }
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};
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}
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namespace llvm {
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template <> struct DenseMapInfo<ObjCSummaryKey> {
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static inline ObjCSummaryKey getEmptyKey() {
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return ObjCSummaryKey(DenseMapInfo<IdentifierInfo*>::getEmptyKey(),
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DenseMapInfo<Selector>::getEmptyKey());
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}
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static inline ObjCSummaryKey getTombstoneKey() {
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return ObjCSummaryKey(DenseMapInfo<IdentifierInfo*>::getTombstoneKey(),
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DenseMapInfo<Selector>::getTombstoneKey());
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}
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static unsigned getHashValue(const ObjCSummaryKey &V) {
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typedef std::pair<IdentifierInfo*, Selector> PairTy;
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return DenseMapInfo<PairTy>::getHashValue(PairTy(V.getIdentifier(),
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V.getSelector()));
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}
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static bool isEqual(const ObjCSummaryKey& LHS, const ObjCSummaryKey& RHS) {
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return LHS.getIdentifier() == RHS.getIdentifier() &&
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LHS.getSelector() == RHS.getSelector();
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}
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};
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} // end llvm namespace
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namespace {
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class ObjCSummaryCache {
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typedef llvm::DenseMap<ObjCSummaryKey, const RetainSummary *> MapTy;
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MapTy M;
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public:
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ObjCSummaryCache() {}
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const RetainSummary * find(const ObjCInterfaceDecl *D, Selector S) {
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// Do a lookup with the (D,S) pair. If we find a match return
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// the iterator.
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ObjCSummaryKey K(D, S);
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MapTy::iterator I = M.find(K);
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if (I != M.end())
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return I->second;
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if (!D)
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return NULL;
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// Walk the super chain. If we find a hit with a parent, we'll end
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// up returning that summary. We actually allow that key (null,S), as
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// we cache summaries for the null ObjCInterfaceDecl* to allow us to
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// generate initial summaries without having to worry about NSObject
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// being declared.
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// FIXME: We may change this at some point.
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for (ObjCInterfaceDecl *C=D->getSuperClass() ;; C=C->getSuperClass()) {
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if ((I = M.find(ObjCSummaryKey(C, S))) != M.end())
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break;
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if (!C)
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return NULL;
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}
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|
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// Cache the summary with original key to make the next lookup faster
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// and return the iterator.
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const RetainSummary *Summ = I->second;
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M[K] = Summ;
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return Summ;
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}
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|
|
const RetainSummary *find(IdentifierInfo* II, Selector S) {
|
|
// FIXME: Class method lookup. Right now we dont' have a good way
|
|
// of going between IdentifierInfo* and the class hierarchy.
|
|
MapTy::iterator I = M.find(ObjCSummaryKey(II, S));
|
|
|
|
if (I == M.end())
|
|
I = M.find(ObjCSummaryKey(S));
|
|
|
|
return I == M.end() ? NULL : I->second;
|
|
}
|
|
|
|
const RetainSummary *& operator[](ObjCSummaryKey K) {
|
|
return M[K];
|
|
}
|
|
|
|
const RetainSummary *& operator[](Selector S) {
|
|
return M[ ObjCSummaryKey(S) ];
|
|
}
|
|
};
|
|
} // end anonymous namespace
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Data structures for managing collections of summaries.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace {
|
|
class RetainSummaryManager {
|
|
|
|
//==-----------------------------------------------------------------==//
|
|
// Typedefs.
|
|
//==-----------------------------------------------------------------==//
|
|
|
|
typedef llvm::DenseMap<const FunctionDecl*, const RetainSummary *>
|
|
FuncSummariesTy;
|
|
|
|
typedef ObjCSummaryCache ObjCMethodSummariesTy;
|
|
|
|
typedef llvm::FoldingSetNodeWrapper<RetainSummary> CachedSummaryNode;
|
|
|
|
//==-----------------------------------------------------------------==//
|
|
// Data.
|
|
//==-----------------------------------------------------------------==//
|
|
|
|
/// Ctx - The ASTContext object for the analyzed ASTs.
|
|
ASTContext &Ctx;
|
|
|
|
/// GCEnabled - Records whether or not the analyzed code runs in GC mode.
|
|
const bool GCEnabled;
|
|
|
|
/// Records whether or not the analyzed code runs in ARC mode.
|
|
const bool ARCEnabled;
|
|
|
|
/// FuncSummaries - A map from FunctionDecls to summaries.
|
|
FuncSummariesTy FuncSummaries;
|
|
|
|
/// ObjCClassMethodSummaries - A map from selectors (for instance methods)
|
|
/// to summaries.
|
|
ObjCMethodSummariesTy ObjCClassMethodSummaries;
|
|
|
|
/// ObjCMethodSummaries - A map from selectors to summaries.
|
|
ObjCMethodSummariesTy ObjCMethodSummaries;
|
|
|
|
/// BPAlloc - A BumpPtrAllocator used for allocating summaries, ArgEffects,
|
|
/// and all other data used by the checker.
|
|
llvm::BumpPtrAllocator BPAlloc;
|
|
|
|
/// AF - A factory for ArgEffects objects.
|
|
ArgEffects::Factory AF;
|
|
|
|
/// ScratchArgs - A holding buffer for construct ArgEffects.
|
|
ArgEffects ScratchArgs;
|
|
|
|
/// ObjCAllocRetE - Default return effect for methods returning Objective-C
|
|
/// objects.
|
|
RetEffect ObjCAllocRetE;
|
|
|
|
/// ObjCInitRetE - Default return effect for init methods returning
|
|
/// Objective-C objects.
|
|
RetEffect ObjCInitRetE;
|
|
|
|
/// SimpleSummaries - Used for uniquing summaries that don't have special
|
|
/// effects.
|
|
llvm::FoldingSet<CachedSummaryNode> SimpleSummaries;
|
|
|
|
//==-----------------------------------------------------------------==//
|
|
// Methods.
|
|
//==-----------------------------------------------------------------==//
|
|
|
|
/// getArgEffects - Returns a persistent ArgEffects object based on the
|
|
/// data in ScratchArgs.
|
|
ArgEffects getArgEffects();
|
|
|
|
enum UnaryFuncKind { cfretain, cfrelease, cfautorelease, cfmakecollectable };
|
|
|
|
const RetainSummary *getUnarySummary(const FunctionType* FT,
|
|
UnaryFuncKind func);
|
|
|
|
const RetainSummary *getCFSummaryCreateRule(const FunctionDecl *FD);
|
|
const RetainSummary *getCFSummaryGetRule(const FunctionDecl *FD);
|
|
const RetainSummary *getCFCreateGetRuleSummary(const FunctionDecl *FD);
|
|
|
|
const RetainSummary *getPersistentSummary(const RetainSummary &OldSumm);
|
|
|
|
const RetainSummary *getPersistentSummary(RetEffect RetEff,
|
|
ArgEffect ReceiverEff = DoNothing,
|
|
ArgEffect DefaultEff = MayEscape) {
|
|
RetainSummary Summ(getArgEffects(), RetEff, DefaultEff, ReceiverEff);
|
|
return getPersistentSummary(Summ);
|
|
}
|
|
|
|
const RetainSummary *getDoNothingSummary() {
|
|
return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing);
|
|
}
|
|
|
|
const RetainSummary *getDefaultSummary() {
|
|
return getPersistentSummary(RetEffect::MakeNoRet(),
|
|
DoNothing, MayEscape);
|
|
}
|
|
|
|
const RetainSummary *getPersistentStopSummary() {
|
|
return getPersistentSummary(RetEffect::MakeNoRet(),
|
|
StopTracking, StopTracking);
|
|
}
|
|
|
|
void InitializeClassMethodSummaries();
|
|
void InitializeMethodSummaries();
|
|
private:
|
|
void addNSObjectClsMethSummary(Selector S, const RetainSummary *Summ) {
|
|
ObjCClassMethodSummaries[S] = Summ;
|
|
}
|
|
|
|
void addNSObjectMethSummary(Selector S, const RetainSummary *Summ) {
|
|
ObjCMethodSummaries[S] = Summ;
|
|
}
|
|
|
|
void addClassMethSummary(const char* Cls, const char* name,
|
|
const RetainSummary *Summ, bool isNullary = true) {
|
|
IdentifierInfo* ClsII = &Ctx.Idents.get(Cls);
|
|
Selector S = isNullary ? GetNullarySelector(name, Ctx)
|
|
: GetUnarySelector(name, Ctx);
|
|
ObjCClassMethodSummaries[ObjCSummaryKey(ClsII, S)] = Summ;
|
|
}
|
|
|
|
void addInstMethSummary(const char* Cls, const char* nullaryName,
|
|
const RetainSummary *Summ) {
|
|
IdentifierInfo* ClsII = &Ctx.Idents.get(Cls);
|
|
Selector S = GetNullarySelector(nullaryName, Ctx);
|
|
ObjCMethodSummaries[ObjCSummaryKey(ClsII, S)] = Summ;
|
|
}
|
|
|
|
void addMethodSummary(IdentifierInfo *ClsII, ObjCMethodSummariesTy &Summaries,
|
|
const RetainSummary *Summ, va_list argp) {
|
|
Selector S = getKeywordSelector(Ctx, argp);
|
|
Summaries[ObjCSummaryKey(ClsII, S)] = Summ;
|
|
}
|
|
|
|
void addInstMethSummary(const char* Cls, const RetainSummary * Summ, ...) {
|
|
va_list argp;
|
|
va_start(argp, Summ);
|
|
addMethodSummary(&Ctx.Idents.get(Cls), ObjCMethodSummaries, Summ, argp);
|
|
va_end(argp);
|
|
}
|
|
|
|
void addClsMethSummary(const char* Cls, const RetainSummary * Summ, ...) {
|
|
va_list argp;
|
|
va_start(argp, Summ);
|
|
addMethodSummary(&Ctx.Idents.get(Cls),ObjCClassMethodSummaries, Summ, argp);
|
|
va_end(argp);
|
|
}
|
|
|
|
void addClsMethSummary(IdentifierInfo *II, const RetainSummary * Summ, ...) {
|
|
va_list argp;
|
|
va_start(argp, Summ);
|
|
addMethodSummary(II, ObjCClassMethodSummaries, Summ, argp);
|
|
va_end(argp);
|
|
}
|
|
|
|
public:
|
|
|
|
RetainSummaryManager(ASTContext &ctx, bool gcenabled, bool usesARC)
|
|
: Ctx(ctx),
|
|
GCEnabled(gcenabled),
|
|
ARCEnabled(usesARC),
|
|
AF(BPAlloc), ScratchArgs(AF.getEmptyMap()),
|
|
ObjCAllocRetE(gcenabled
|
|
? RetEffect::MakeGCNotOwned()
|
|
: (usesARC ? RetEffect::MakeNotOwned(RetEffect::ObjC)
|
|
: RetEffect::MakeOwned(RetEffect::ObjC, true))),
|
|
ObjCInitRetE(gcenabled
|
|
? RetEffect::MakeGCNotOwned()
|
|
: (usesARC ? RetEffect::MakeNotOwned(RetEffect::ObjC)
|
|
: RetEffect::MakeOwnedWhenTrackedReceiver())) {
|
|
InitializeClassMethodSummaries();
|
|
InitializeMethodSummaries();
|
|
}
|
|
|
|
const RetainSummary *getSummary(const CallEvent &Call,
|
|
ProgramStateRef State = 0);
|
|
|
|
const RetainSummary *getFunctionSummary(const FunctionDecl *FD);
|
|
|
|
const RetainSummary *getMethodSummary(Selector S, const ObjCInterfaceDecl *ID,
|
|
const ObjCMethodDecl *MD,
|
|
QualType RetTy,
|
|
ObjCMethodSummariesTy &CachedSummaries);
|
|
|
|
const RetainSummary *getInstanceMethodSummary(const ObjCMethodCall &M,
|
|
ProgramStateRef State);
|
|
|
|
const RetainSummary *getClassMethodSummary(const ObjCMethodCall &M) {
|
|
assert(!M.isInstanceMessage());
|
|
const ObjCInterfaceDecl *Class = M.getReceiverInterface();
|
|
|
|
return getMethodSummary(M.getSelector(), Class, M.getDecl(),
|
|
M.getResultType(), ObjCClassMethodSummaries);
|
|
}
|
|
|
|
/// getMethodSummary - This version of getMethodSummary is used to query
|
|
/// the summary for the current method being analyzed.
|
|
const RetainSummary *getMethodSummary(const ObjCMethodDecl *MD) {
|
|
const ObjCInterfaceDecl *ID = MD->getClassInterface();
|
|
Selector S = MD->getSelector();
|
|
QualType ResultTy = MD->getReturnType();
|
|
|
|
ObjCMethodSummariesTy *CachedSummaries;
|
|
if (MD->isInstanceMethod())
|
|
CachedSummaries = &ObjCMethodSummaries;
|
|
else
|
|
CachedSummaries = &ObjCClassMethodSummaries;
|
|
|
|
return getMethodSummary(S, ID, MD, ResultTy, *CachedSummaries);
|
|
}
|
|
|
|
const RetainSummary *getStandardMethodSummary(const ObjCMethodDecl *MD,
|
|
Selector S, QualType RetTy);
|
|
|
|
/// Determine if there is a special return effect for this function or method.
|
|
Optional<RetEffect> getRetEffectFromAnnotations(QualType RetTy,
|
|
const Decl *D);
|
|
|
|
void updateSummaryFromAnnotations(const RetainSummary *&Summ,
|
|
const ObjCMethodDecl *MD);
|
|
|
|
void updateSummaryFromAnnotations(const RetainSummary *&Summ,
|
|
const FunctionDecl *FD);
|
|
|
|
void updateSummaryForCall(const RetainSummary *&Summ,
|
|
const CallEvent &Call);
|
|
|
|
bool isGCEnabled() const { return GCEnabled; }
|
|
|
|
bool isARCEnabled() const { return ARCEnabled; }
|
|
|
|
bool isARCorGCEnabled() const { return GCEnabled || ARCEnabled; }
|
|
|
|
RetEffect getObjAllocRetEffect() const { return ObjCAllocRetE; }
|
|
|
|
friend class RetainSummaryTemplate;
|
|
};
|
|
|
|
// Used to avoid allocating long-term (BPAlloc'd) memory for default retain
|
|
// summaries. If a function or method looks like it has a default summary, but
|
|
// it has annotations, the annotations are added to the stack-based template
|
|
// and then copied into managed memory.
|
|
class RetainSummaryTemplate {
|
|
RetainSummaryManager &Manager;
|
|
const RetainSummary *&RealSummary;
|
|
RetainSummary ScratchSummary;
|
|
bool Accessed;
|
|
public:
|
|
RetainSummaryTemplate(const RetainSummary *&real, RetainSummaryManager &mgr)
|
|
: Manager(mgr), RealSummary(real), ScratchSummary(*real), Accessed(false) {}
|
|
|
|
~RetainSummaryTemplate() {
|
|
if (Accessed)
|
|
RealSummary = Manager.getPersistentSummary(ScratchSummary);
|
|
}
|
|
|
|
RetainSummary &operator*() {
|
|
Accessed = true;
|
|
return ScratchSummary;
|
|
}
|
|
|
|
RetainSummary *operator->() {
|
|
Accessed = true;
|
|
return &ScratchSummary;
|
|
}
|
|
};
|
|
|
|
} // end anonymous namespace
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Implementation of checker data structures.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
ArgEffects RetainSummaryManager::getArgEffects() {
|
|
ArgEffects AE = ScratchArgs;
|
|
ScratchArgs = AF.getEmptyMap();
|
|
return AE;
|
|
}
|
|
|
|
const RetainSummary *
|
|
RetainSummaryManager::getPersistentSummary(const RetainSummary &OldSumm) {
|
|
// Unique "simple" summaries -- those without ArgEffects.
|
|
if (OldSumm.isSimple()) {
|
|
llvm::FoldingSetNodeID ID;
|
|
OldSumm.Profile(ID);
|
|
|
|
void *Pos;
|
|
CachedSummaryNode *N = SimpleSummaries.FindNodeOrInsertPos(ID, Pos);
|
|
|
|
if (!N) {
|
|
N = (CachedSummaryNode *) BPAlloc.Allocate<CachedSummaryNode>();
|
|
new (N) CachedSummaryNode(OldSumm);
|
|
SimpleSummaries.InsertNode(N, Pos);
|
|
}
|
|
|
|
return &N->getValue();
|
|
}
|
|
|
|
RetainSummary *Summ = (RetainSummary *) BPAlloc.Allocate<RetainSummary>();
|
|
new (Summ) RetainSummary(OldSumm);
|
|
return Summ;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Summary creation for functions (largely uses of Core Foundation).
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
static bool isRetain(const FunctionDecl *FD, StringRef FName) {
|
|
return FName.endswith("Retain");
|
|
}
|
|
|
|
static bool isRelease(const FunctionDecl *FD, StringRef FName) {
|
|
return FName.endswith("Release");
|
|
}
|
|
|
|
static bool isAutorelease(const FunctionDecl *FD, StringRef FName) {
|
|
return FName.endswith("Autorelease");
|
|
}
|
|
|
|
static bool isMakeCollectable(const FunctionDecl *FD, StringRef FName) {
|
|
// FIXME: Remove FunctionDecl parameter.
|
|
// FIXME: Is it really okay if MakeCollectable isn't a suffix?
|
|
return FName.find("MakeCollectable") != StringRef::npos;
|
|
}
|
|
|
|
static ArgEffect getStopTrackingHardEquivalent(ArgEffect E) {
|
|
switch (E) {
|
|
case DoNothing:
|
|
case Autorelease:
|
|
case DecRefBridgedTransferred:
|
|
case IncRef:
|
|
case IncRefMsg:
|
|
case MakeCollectable:
|
|
case MayEscape:
|
|
case StopTracking:
|
|
case StopTrackingHard:
|
|
return StopTrackingHard;
|
|
case DecRef:
|
|
case DecRefAndStopTrackingHard:
|
|
return DecRefAndStopTrackingHard;
|
|
case DecRefMsg:
|
|
case DecRefMsgAndStopTrackingHard:
|
|
return DecRefMsgAndStopTrackingHard;
|
|
case Dealloc:
|
|
return Dealloc;
|
|
}
|
|
|
|
llvm_unreachable("Unknown ArgEffect kind");
|
|
}
|
|
|
|
void RetainSummaryManager::updateSummaryForCall(const RetainSummary *&S,
|
|
const CallEvent &Call) {
|
|
if (Call.hasNonZeroCallbackArg()) {
|
|
ArgEffect RecEffect =
|
|
getStopTrackingHardEquivalent(S->getReceiverEffect());
|
|
ArgEffect DefEffect =
|
|
getStopTrackingHardEquivalent(S->getDefaultArgEffect());
|
|
|
|
ArgEffects CustomArgEffects = S->getArgEffects();
|
|
for (ArgEffects::iterator I = CustomArgEffects.begin(),
|
|
E = CustomArgEffects.end();
|
|
I != E; ++I) {
|
|
ArgEffect Translated = getStopTrackingHardEquivalent(I->second);
|
|
if (Translated != DefEffect)
|
|
ScratchArgs = AF.add(ScratchArgs, I->first, Translated);
|
|
}
|
|
|
|
RetEffect RE = RetEffect::MakeNoRetHard();
|
|
|
|
// Special cases where the callback argument CANNOT free the return value.
|
|
// This can generally only happen if we know that the callback will only be
|
|
// called when the return value is already being deallocated.
|
|
if (const SimpleFunctionCall *FC = dyn_cast<SimpleFunctionCall>(&Call)) {
|
|
if (IdentifierInfo *Name = FC->getDecl()->getIdentifier()) {
|
|
// When the CGBitmapContext is deallocated, the callback here will free
|
|
// the associated data buffer.
|
|
if (Name->isStr("CGBitmapContextCreateWithData"))
|
|
RE = S->getRetEffect();
|
|
}
|
|
}
|
|
|
|
S = getPersistentSummary(RE, RecEffect, DefEffect);
|
|
}
|
|
|
|
// Special case '[super init];' and '[self init];'
|
|
//
|
|
// Even though calling '[super init]' without assigning the result to self
|
|
// and checking if the parent returns 'nil' is a bad pattern, it is common.
|
|
// Additionally, our Self Init checker already warns about it. To avoid
|
|
// overwhelming the user with messages from both checkers, we model the case
|
|
// of '[super init]' in cases when it is not consumed by another expression
|
|
// as if the call preserves the value of 'self'; essentially, assuming it can
|
|
// never fail and return 'nil'.
|
|
// Note, we don't want to just stop tracking the value since we want the
|
|
// RetainCount checker to report leaks and use-after-free if SelfInit checker
|
|
// is turned off.
|
|
if (const ObjCMethodCall *MC = dyn_cast<ObjCMethodCall>(&Call)) {
|
|
if (MC->getMethodFamily() == OMF_init && MC->isReceiverSelfOrSuper()) {
|
|
|
|
// Check if the message is not consumed, we know it will not be used in
|
|
// an assignment, ex: "self = [super init]".
|
|
const Expr *ME = MC->getOriginExpr();
|
|
const LocationContext *LCtx = MC->getLocationContext();
|
|
ParentMap &PM = LCtx->getAnalysisDeclContext()->getParentMap();
|
|
if (!PM.isConsumedExpr(ME)) {
|
|
RetainSummaryTemplate ModifiableSummaryTemplate(S, *this);
|
|
ModifiableSummaryTemplate->setReceiverEffect(DoNothing);
|
|
ModifiableSummaryTemplate->setRetEffect(RetEffect::MakeNoRet());
|
|
}
|
|
}
|
|
|
|
}
|
|
}
|
|
|
|
const RetainSummary *
|
|
RetainSummaryManager::getSummary(const CallEvent &Call,
|
|
ProgramStateRef State) {
|
|
const RetainSummary *Summ;
|
|
switch (Call.getKind()) {
|
|
case CE_Function:
|
|
Summ = getFunctionSummary(cast<SimpleFunctionCall>(Call).getDecl());
|
|
break;
|
|
case CE_CXXMember:
|
|
case CE_CXXMemberOperator:
|
|
case CE_Block:
|
|
case CE_CXXConstructor:
|
|
case CE_CXXDestructor:
|
|
case CE_CXXAllocator:
|
|
// FIXME: These calls are currently unsupported.
|
|
return getPersistentStopSummary();
|
|
case CE_ObjCMessage: {
|
|
const ObjCMethodCall &Msg = cast<ObjCMethodCall>(Call);
|
|
if (Msg.isInstanceMessage())
|
|
Summ = getInstanceMethodSummary(Msg, State);
|
|
else
|
|
Summ = getClassMethodSummary(Msg);
|
|
break;
|
|
}
|
|
}
|
|
|
|
updateSummaryForCall(Summ, Call);
|
|
|
|
assert(Summ && "Unknown call type?");
|
|
return Summ;
|
|
}
|
|
|
|
const RetainSummary *
|
|
RetainSummaryManager::getFunctionSummary(const FunctionDecl *FD) {
|
|
// If we don't know what function we're calling, use our default summary.
|
|
if (!FD)
|
|
return getDefaultSummary();
|
|
|
|
// Look up a summary in our cache of FunctionDecls -> Summaries.
|
|
FuncSummariesTy::iterator I = FuncSummaries.find(FD);
|
|
if (I != FuncSummaries.end())
|
|
return I->second;
|
|
|
|
// No summary? Generate one.
|
|
const RetainSummary *S = 0;
|
|
bool AllowAnnotations = true;
|
|
|
|
do {
|
|
// We generate "stop" summaries for implicitly defined functions.
|
|
if (FD->isImplicit()) {
|
|
S = getPersistentStopSummary();
|
|
break;
|
|
}
|
|
|
|
// [PR 3337] Use 'getAs<FunctionType>' to strip away any typedefs on the
|
|
// function's type.
|
|
const FunctionType* FT = FD->getType()->getAs<FunctionType>();
|
|
const IdentifierInfo *II = FD->getIdentifier();
|
|
if (!II)
|
|
break;
|
|
|
|
StringRef FName = II->getName();
|
|
|
|
// Strip away preceding '_'. Doing this here will effect all the checks
|
|
// down below.
|
|
FName = FName.substr(FName.find_first_not_of('_'));
|
|
|
|
// Inspect the result type.
|
|
QualType RetTy = FT->getReturnType();
|
|
|
|
// FIXME: This should all be refactored into a chain of "summary lookup"
|
|
// filters.
|
|
assert(ScratchArgs.isEmpty());
|
|
|
|
if (FName == "pthread_create" || FName == "pthread_setspecific") {
|
|
// Part of: <rdar://problem/7299394> and <rdar://problem/11282706>.
|
|
// This will be addressed better with IPA.
|
|
S = getPersistentStopSummary();
|
|
} else if (FName == "NSMakeCollectable") {
|
|
// Handle: id NSMakeCollectable(CFTypeRef)
|
|
S = (RetTy->isObjCIdType())
|
|
? getUnarySummary(FT, cfmakecollectable)
|
|
: getPersistentStopSummary();
|
|
// The headers on OS X 10.8 use cf_consumed/ns_returns_retained,
|
|
// but we can fully model NSMakeCollectable ourselves.
|
|
AllowAnnotations = false;
|
|
} else if (FName == "CFPlugInInstanceCreate") {
|
|
S = getPersistentSummary(RetEffect::MakeNoRet());
|
|
} else if (FName == "IOBSDNameMatching" ||
|
|
FName == "IOServiceMatching" ||
|
|
FName == "IOServiceNameMatching" ||
|
|
FName == "IORegistryEntrySearchCFProperty" ||
|
|
FName == "IORegistryEntryIDMatching" ||
|
|
FName == "IOOpenFirmwarePathMatching") {
|
|
// Part of <rdar://problem/6961230>. (IOKit)
|
|
// This should be addressed using a API table.
|
|
S = getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF, true),
|
|
DoNothing, DoNothing);
|
|
} else if (FName == "IOServiceGetMatchingService" ||
|
|
FName == "IOServiceGetMatchingServices") {
|
|
// FIXES: <rdar://problem/6326900>
|
|
// This should be addressed using a API table. This strcmp is also
|
|
// a little gross, but there is no need to super optimize here.
|
|
ScratchArgs = AF.add(ScratchArgs, 1, DecRef);
|
|
S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing);
|
|
} else if (FName == "IOServiceAddNotification" ||
|
|
FName == "IOServiceAddMatchingNotification") {
|
|
// Part of <rdar://problem/6961230>. (IOKit)
|
|
// This should be addressed using a API table.
|
|
ScratchArgs = AF.add(ScratchArgs, 2, DecRef);
|
|
S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing);
|
|
} else if (FName == "CVPixelBufferCreateWithBytes") {
|
|
// FIXES: <rdar://problem/7283567>
|
|
// Eventually this can be improved by recognizing that the pixel
|
|
// buffer passed to CVPixelBufferCreateWithBytes is released via
|
|
// a callback and doing full IPA to make sure this is done correctly.
|
|
// FIXME: This function has an out parameter that returns an
|
|
// allocated object.
|
|
ScratchArgs = AF.add(ScratchArgs, 7, StopTracking);
|
|
S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing);
|
|
} else if (FName == "CGBitmapContextCreateWithData") {
|
|
// FIXES: <rdar://problem/7358899>
|
|
// Eventually this can be improved by recognizing that 'releaseInfo'
|
|
// passed to CGBitmapContextCreateWithData is released via
|
|
// a callback and doing full IPA to make sure this is done correctly.
|
|
ScratchArgs = AF.add(ScratchArgs, 8, StopTracking);
|
|
S = getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF, true),
|
|
DoNothing, DoNothing);
|
|
} else if (FName == "CVPixelBufferCreateWithPlanarBytes") {
|
|
// FIXES: <rdar://problem/7283567>
|
|
// Eventually this can be improved by recognizing that the pixel
|
|
// buffer passed to CVPixelBufferCreateWithPlanarBytes is released
|
|
// via a callback and doing full IPA to make sure this is done
|
|
// correctly.
|
|
ScratchArgs = AF.add(ScratchArgs, 12, StopTracking);
|
|
S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing);
|
|
} else if (FName == "dispatch_set_context" ||
|
|
FName == "xpc_connection_set_context") {
|
|
// <rdar://problem/11059275> - The analyzer currently doesn't have
|
|
// a good way to reason about the finalizer function for libdispatch.
|
|
// If we pass a context object that is memory managed, stop tracking it.
|
|
// <rdar://problem/13783514> - Same problem, but for XPC.
|
|
// FIXME: this hack should possibly go away once we can handle
|
|
// libdispatch and XPC finalizers.
|
|
ScratchArgs = AF.add(ScratchArgs, 1, StopTracking);
|
|
S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing);
|
|
} else if (FName.startswith("NSLog")) {
|
|
S = getDoNothingSummary();
|
|
} else if (FName.startswith("NS") &&
|
|
(FName.find("Insert") != StringRef::npos)) {
|
|
// Whitelist NSXXInsertXX, for example NSMapInsertIfAbsent, since they can
|
|
// be deallocated by NSMapRemove. (radar://11152419)
|
|
ScratchArgs = AF.add(ScratchArgs, 1, StopTracking);
|
|
ScratchArgs = AF.add(ScratchArgs, 2, StopTracking);
|
|
S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing);
|
|
}
|
|
|
|
// Did we get a summary?
|
|
if (S)
|
|
break;
|
|
|
|
if (RetTy->isPointerType()) {
|
|
// For CoreFoundation ('CF') types.
|
|
if (cocoa::isRefType(RetTy, "CF", FName)) {
|
|
if (isRetain(FD, FName)) {
|
|
S = getUnarySummary(FT, cfretain);
|
|
} else if (isAutorelease(FD, FName)) {
|
|
S = getUnarySummary(FT, cfautorelease);
|
|
// The headers use cf_consumed, but we can fully model CFAutorelease
|
|
// ourselves.
|
|
AllowAnnotations = false;
|
|
} else if (isMakeCollectable(FD, FName)) {
|
|
S = getUnarySummary(FT, cfmakecollectable);
|
|
AllowAnnotations = false;
|
|
} else {
|
|
S = getCFCreateGetRuleSummary(FD);
|
|
}
|
|
|
|
break;
|
|
}
|
|
|
|
// For CoreGraphics ('CG') types.
|
|
if (cocoa::isRefType(RetTy, "CG", FName)) {
|
|
if (isRetain(FD, FName))
|
|
S = getUnarySummary(FT, cfretain);
|
|
else
|
|
S = getCFCreateGetRuleSummary(FD);
|
|
|
|
break;
|
|
}
|
|
|
|
// For the Disk Arbitration API (DiskArbitration/DADisk.h)
|
|
if (cocoa::isRefType(RetTy, "DADisk") ||
|
|
cocoa::isRefType(RetTy, "DADissenter") ||
|
|
cocoa::isRefType(RetTy, "DASessionRef")) {
|
|
S = getCFCreateGetRuleSummary(FD);
|
|
break;
|
|
}
|
|
|
|
if (FD->hasAttr<CFAuditedTransferAttr>()) {
|
|
S = getCFCreateGetRuleSummary(FD);
|
|
break;
|
|
}
|
|
|
|
break;
|
|
}
|
|
|
|
// Check for release functions, the only kind of functions that we care
|
|
// about that don't return a pointer type.
|
|
if (FName[0] == 'C' && (FName[1] == 'F' || FName[1] == 'G')) {
|
|
// Test for 'CGCF'.
|
|
FName = FName.substr(FName.startswith("CGCF") ? 4 : 2);
|
|
|
|
if (isRelease(FD, FName))
|
|
S = getUnarySummary(FT, cfrelease);
|
|
else {
|
|
assert (ScratchArgs.isEmpty());
|
|
// Remaining CoreFoundation and CoreGraphics functions.
|
|
// We use to assume that they all strictly followed the ownership idiom
|
|
// and that ownership cannot be transferred. While this is technically
|
|
// correct, many methods allow a tracked object to escape. For example:
|
|
//
|
|
// CFMutableDictionaryRef x = CFDictionaryCreateMutable(...);
|
|
// CFDictionaryAddValue(y, key, x);
|
|
// CFRelease(x);
|
|
// ... it is okay to use 'x' since 'y' has a reference to it
|
|
//
|
|
// We handle this and similar cases with the follow heuristic. If the
|
|
// function name contains "InsertValue", "SetValue", "AddValue",
|
|
// "AppendValue", or "SetAttribute", then we assume that arguments may
|
|
// "escape." This means that something else holds on to the object,
|
|
// allowing it be used even after its local retain count drops to 0.
|
|
ArgEffect E = (StrInStrNoCase(FName, "InsertValue") != StringRef::npos||
|
|
StrInStrNoCase(FName, "AddValue") != StringRef::npos ||
|
|
StrInStrNoCase(FName, "SetValue") != StringRef::npos ||
|
|
StrInStrNoCase(FName, "AppendValue") != StringRef::npos||
|
|
StrInStrNoCase(FName, "SetAttribute") != StringRef::npos)
|
|
? MayEscape : DoNothing;
|
|
|
|
S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, E);
|
|
}
|
|
}
|
|
}
|
|
while (0);
|
|
|
|
// If we got all the way here without any luck, use a default summary.
|
|
if (!S)
|
|
S = getDefaultSummary();
|
|
|
|
// Annotations override defaults.
|
|
if (AllowAnnotations)
|
|
updateSummaryFromAnnotations(S, FD);
|
|
|
|
FuncSummaries[FD] = S;
|
|
return S;
|
|
}
|
|
|
|
const RetainSummary *
|
|
RetainSummaryManager::getCFCreateGetRuleSummary(const FunctionDecl *FD) {
|
|
if (coreFoundation::followsCreateRule(FD))
|
|
return getCFSummaryCreateRule(FD);
|
|
|
|
return getCFSummaryGetRule(FD);
|
|
}
|
|
|
|
const RetainSummary *
|
|
RetainSummaryManager::getUnarySummary(const FunctionType* FT,
|
|
UnaryFuncKind func) {
|
|
|
|
// Sanity check that this is *really* a unary function. This can
|
|
// happen if people do weird things.
|
|
const FunctionProtoType* FTP = dyn_cast<FunctionProtoType>(FT);
|
|
if (!FTP || FTP->getNumParams() != 1)
|
|
return getPersistentStopSummary();
|
|
|
|
assert (ScratchArgs.isEmpty());
|
|
|
|
ArgEffect Effect;
|
|
switch (func) {
|
|
case cfretain: Effect = IncRef; break;
|
|
case cfrelease: Effect = DecRef; break;
|
|
case cfautorelease: Effect = Autorelease; break;
|
|
case cfmakecollectable: Effect = MakeCollectable; break;
|
|
}
|
|
|
|
ScratchArgs = AF.add(ScratchArgs, 0, Effect);
|
|
return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing);
|
|
}
|
|
|
|
const RetainSummary *
|
|
RetainSummaryManager::getCFSummaryCreateRule(const FunctionDecl *FD) {
|
|
assert (ScratchArgs.isEmpty());
|
|
|
|
return getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF, true));
|
|
}
|
|
|
|
const RetainSummary *
|
|
RetainSummaryManager::getCFSummaryGetRule(const FunctionDecl *FD) {
|
|
assert (ScratchArgs.isEmpty());
|
|
return getPersistentSummary(RetEffect::MakeNotOwned(RetEffect::CF),
|
|
DoNothing, DoNothing);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Summary creation for Selectors.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
Optional<RetEffect>
|
|
RetainSummaryManager::getRetEffectFromAnnotations(QualType RetTy,
|
|
const Decl *D) {
|
|
if (cocoa::isCocoaObjectRef(RetTy)) {
|
|
if (D->hasAttr<NSReturnsRetainedAttr>())
|
|
return ObjCAllocRetE;
|
|
|
|
if (D->hasAttr<NSReturnsNotRetainedAttr>() ||
|
|
D->hasAttr<NSReturnsAutoreleasedAttr>())
|
|
return RetEffect::MakeNotOwned(RetEffect::ObjC);
|
|
|
|
} else if (!RetTy->isPointerType()) {
|
|
return None;
|
|
}
|
|
|
|
if (D->hasAttr<CFReturnsRetainedAttr>())
|
|
return RetEffect::MakeOwned(RetEffect::CF, true);
|
|
|
|
if (D->hasAttr<CFReturnsNotRetainedAttr>())
|
|
return RetEffect::MakeNotOwned(RetEffect::CF);
|
|
|
|
return None;
|
|
}
|
|
|
|
void
|
|
RetainSummaryManager::updateSummaryFromAnnotations(const RetainSummary *&Summ,
|
|
const FunctionDecl *FD) {
|
|
if (!FD)
|
|
return;
|
|
|
|
assert(Summ && "Must have a summary to add annotations to.");
|
|
RetainSummaryTemplate Template(Summ, *this);
|
|
|
|
// Effects on the parameters.
|
|
unsigned parm_idx = 0;
|
|
for (FunctionDecl::param_const_iterator pi = FD->param_begin(),
|
|
pe = FD->param_end(); pi != pe; ++pi, ++parm_idx) {
|
|
const ParmVarDecl *pd = *pi;
|
|
if (pd->hasAttr<NSConsumedAttr>())
|
|
Template->addArg(AF, parm_idx, DecRefMsg);
|
|
else if (pd->hasAttr<CFConsumedAttr>())
|
|
Template->addArg(AF, parm_idx, DecRef);
|
|
}
|
|
|
|
QualType RetTy = FD->getReturnType();
|
|
if (Optional<RetEffect> RetE = getRetEffectFromAnnotations(RetTy, FD))
|
|
Template->setRetEffect(*RetE);
|
|
}
|
|
|
|
void
|
|
RetainSummaryManager::updateSummaryFromAnnotations(const RetainSummary *&Summ,
|
|
const ObjCMethodDecl *MD) {
|
|
if (!MD)
|
|
return;
|
|
|
|
assert(Summ && "Must have a valid summary to add annotations to");
|
|
RetainSummaryTemplate Template(Summ, *this);
|
|
|
|
// Effects on the receiver.
|
|
if (MD->hasAttr<NSConsumesSelfAttr>())
|
|
Template->setReceiverEffect(DecRefMsg);
|
|
|
|
// Effects on the parameters.
|
|
unsigned parm_idx = 0;
|
|
for (ObjCMethodDecl::param_const_iterator
|
|
pi=MD->param_begin(), pe=MD->param_end();
|
|
pi != pe; ++pi, ++parm_idx) {
|
|
const ParmVarDecl *pd = *pi;
|
|
if (pd->hasAttr<NSConsumedAttr>())
|
|
Template->addArg(AF, parm_idx, DecRefMsg);
|
|
else if (pd->hasAttr<CFConsumedAttr>()) {
|
|
Template->addArg(AF, parm_idx, DecRef);
|
|
}
|
|
}
|
|
|
|
QualType RetTy = MD->getReturnType();
|
|
if (Optional<RetEffect> RetE = getRetEffectFromAnnotations(RetTy, MD))
|
|
Template->setRetEffect(*RetE);
|
|
}
|
|
|
|
const RetainSummary *
|
|
RetainSummaryManager::getStandardMethodSummary(const ObjCMethodDecl *MD,
|
|
Selector S, QualType RetTy) {
|
|
// Any special effects?
|
|
ArgEffect ReceiverEff = DoNothing;
|
|
RetEffect ResultEff = RetEffect::MakeNoRet();
|
|
|
|
// Check the method family, and apply any default annotations.
|
|
switch (MD ? MD->getMethodFamily() : S.getMethodFamily()) {
|
|
case OMF_None:
|
|
case OMF_performSelector:
|
|
// Assume all Objective-C methods follow Cocoa Memory Management rules.
|
|
// FIXME: Does the non-threaded performSelector family really belong here?
|
|
// The selector could be, say, @selector(copy).
|
|
if (cocoa::isCocoaObjectRef(RetTy))
|
|
ResultEff = RetEffect::MakeNotOwned(RetEffect::ObjC);
|
|
else if (coreFoundation::isCFObjectRef(RetTy)) {
|
|
// ObjCMethodDecl currently doesn't consider CF objects as valid return
|
|
// values for alloc, new, copy, or mutableCopy, so we have to
|
|
// double-check with the selector. This is ugly, but there aren't that
|
|
// many Objective-C methods that return CF objects, right?
|
|
if (MD) {
|
|
switch (S.getMethodFamily()) {
|
|
case OMF_alloc:
|
|
case OMF_new:
|
|
case OMF_copy:
|
|
case OMF_mutableCopy:
|
|
ResultEff = RetEffect::MakeOwned(RetEffect::CF, true);
|
|
break;
|
|
default:
|
|
ResultEff = RetEffect::MakeNotOwned(RetEffect::CF);
|
|
break;
|
|
}
|
|
} else {
|
|
ResultEff = RetEffect::MakeNotOwned(RetEffect::CF);
|
|
}
|
|
}
|
|
break;
|
|
case OMF_init:
|
|
ResultEff = ObjCInitRetE;
|
|
ReceiverEff = DecRefMsg;
|
|
break;
|
|
case OMF_alloc:
|
|
case OMF_new:
|
|
case OMF_copy:
|
|
case OMF_mutableCopy:
|
|
if (cocoa::isCocoaObjectRef(RetTy))
|
|
ResultEff = ObjCAllocRetE;
|
|
else if (coreFoundation::isCFObjectRef(RetTy))
|
|
ResultEff = RetEffect::MakeOwned(RetEffect::CF, true);
|
|
break;
|
|
case OMF_autorelease:
|
|
ReceiverEff = Autorelease;
|
|
break;
|
|
case OMF_retain:
|
|
ReceiverEff = IncRefMsg;
|
|
break;
|
|
case OMF_release:
|
|
ReceiverEff = DecRefMsg;
|
|
break;
|
|
case OMF_dealloc:
|
|
ReceiverEff = Dealloc;
|
|
break;
|
|
case OMF_self:
|
|
// -self is handled specially by the ExprEngine to propagate the receiver.
|
|
break;
|
|
case OMF_retainCount:
|
|
case OMF_finalize:
|
|
// These methods don't return objects.
|
|
break;
|
|
}
|
|
|
|
// If one of the arguments in the selector has the keyword 'delegate' we
|
|
// should stop tracking the reference count for the receiver. This is
|
|
// because the reference count is quite possibly handled by a delegate
|
|
// method.
|
|
if (S.isKeywordSelector()) {
|
|
for (unsigned i = 0, e = S.getNumArgs(); i != e; ++i) {
|
|
StringRef Slot = S.getNameForSlot(i);
|
|
if (Slot.substr(Slot.size() - 8).equals_lower("delegate")) {
|
|
if (ResultEff == ObjCInitRetE)
|
|
ResultEff = RetEffect::MakeNoRetHard();
|
|
else
|
|
ReceiverEff = StopTrackingHard;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (ScratchArgs.isEmpty() && ReceiverEff == DoNothing &&
|
|
ResultEff.getKind() == RetEffect::NoRet)
|
|
return getDefaultSummary();
|
|
|
|
return getPersistentSummary(ResultEff, ReceiverEff, MayEscape);
|
|
}
|
|
|
|
const RetainSummary *
|
|
RetainSummaryManager::getInstanceMethodSummary(const ObjCMethodCall &Msg,
|
|
ProgramStateRef State) {
|
|
const ObjCInterfaceDecl *ReceiverClass = 0;
|
|
|
|
// We do better tracking of the type of the object than the core ExprEngine.
|
|
// See if we have its type in our private state.
|
|
// FIXME: Eventually replace the use of state->get<RefBindings> with
|
|
// a generic API for reasoning about the Objective-C types of symbolic
|
|
// objects.
|
|
SVal ReceiverV = Msg.getReceiverSVal();
|
|
if (SymbolRef Sym = ReceiverV.getAsLocSymbol())
|
|
if (const RefVal *T = getRefBinding(State, Sym))
|
|
if (const ObjCObjectPointerType *PT =
|
|
T->getType()->getAs<ObjCObjectPointerType>())
|
|
ReceiverClass = PT->getInterfaceDecl();
|
|
|
|
// If we don't know what kind of object this is, fall back to its static type.
|
|
if (!ReceiverClass)
|
|
ReceiverClass = Msg.getReceiverInterface();
|
|
|
|
// FIXME: The receiver could be a reference to a class, meaning that
|
|
// we should use the class method.
|
|
// id x = [NSObject class];
|
|
// [x performSelector:... withObject:... afterDelay:...];
|
|
Selector S = Msg.getSelector();
|
|
const ObjCMethodDecl *Method = Msg.getDecl();
|
|
if (!Method && ReceiverClass)
|
|
Method = ReceiverClass->getInstanceMethod(S);
|
|
|
|
return getMethodSummary(S, ReceiverClass, Method, Msg.getResultType(),
|
|
ObjCMethodSummaries);
|
|
}
|
|
|
|
const RetainSummary *
|
|
RetainSummaryManager::getMethodSummary(Selector S, const ObjCInterfaceDecl *ID,
|
|
const ObjCMethodDecl *MD, QualType RetTy,
|
|
ObjCMethodSummariesTy &CachedSummaries) {
|
|
|
|
// Look up a summary in our summary cache.
|
|
const RetainSummary *Summ = CachedSummaries.find(ID, S);
|
|
|
|
if (!Summ) {
|
|
Summ = getStandardMethodSummary(MD, S, RetTy);
|
|
|
|
// Annotations override defaults.
|
|
updateSummaryFromAnnotations(Summ, MD);
|
|
|
|
// Memoize the summary.
|
|
CachedSummaries[ObjCSummaryKey(ID, S)] = Summ;
|
|
}
|
|
|
|
return Summ;
|
|
}
|
|
|
|
void RetainSummaryManager::InitializeClassMethodSummaries() {
|
|
assert(ScratchArgs.isEmpty());
|
|
// Create the [NSAssertionHandler currentHander] summary.
|
|
addClassMethSummary("NSAssertionHandler", "currentHandler",
|
|
getPersistentSummary(RetEffect::MakeNotOwned(RetEffect::ObjC)));
|
|
|
|
// Create the [NSAutoreleasePool addObject:] summary.
|
|
ScratchArgs = AF.add(ScratchArgs, 0, Autorelease);
|
|
addClassMethSummary("NSAutoreleasePool", "addObject",
|
|
getPersistentSummary(RetEffect::MakeNoRet(),
|
|
DoNothing, Autorelease));
|
|
}
|
|
|
|
void RetainSummaryManager::InitializeMethodSummaries() {
|
|
|
|
assert (ScratchArgs.isEmpty());
|
|
|
|
// Create the "init" selector. It just acts as a pass-through for the
|
|
// receiver.
|
|
const RetainSummary *InitSumm = getPersistentSummary(ObjCInitRetE, DecRefMsg);
|
|
addNSObjectMethSummary(GetNullarySelector("init", Ctx), InitSumm);
|
|
|
|
// awakeAfterUsingCoder: behaves basically like an 'init' method. It
|
|
// claims the receiver and returns a retained object.
|
|
addNSObjectMethSummary(GetUnarySelector("awakeAfterUsingCoder", Ctx),
|
|
InitSumm);
|
|
|
|
// The next methods are allocators.
|
|
const RetainSummary *AllocSumm = getPersistentSummary(ObjCAllocRetE);
|
|
const RetainSummary *CFAllocSumm =
|
|
getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF, true));
|
|
|
|
// Create the "retain" selector.
|
|
RetEffect NoRet = RetEffect::MakeNoRet();
|
|
const RetainSummary *Summ = getPersistentSummary(NoRet, IncRefMsg);
|
|
addNSObjectMethSummary(GetNullarySelector("retain", Ctx), Summ);
|
|
|
|
// Create the "release" selector.
|
|
Summ = getPersistentSummary(NoRet, DecRefMsg);
|
|
addNSObjectMethSummary(GetNullarySelector("release", Ctx), Summ);
|
|
|
|
// Create the -dealloc summary.
|
|
Summ = getPersistentSummary(NoRet, Dealloc);
|
|
addNSObjectMethSummary(GetNullarySelector("dealloc", Ctx), Summ);
|
|
|
|
// Create the "autorelease" selector.
|
|
Summ = getPersistentSummary(NoRet, Autorelease);
|
|
addNSObjectMethSummary(GetNullarySelector("autorelease", Ctx), Summ);
|
|
|
|
// For NSWindow, allocated objects are (initially) self-owned.
|
|
// FIXME: For now we opt for false negatives with NSWindow, as these objects
|
|
// self-own themselves. However, they only do this once they are displayed.
|
|
// Thus, we need to track an NSWindow's display status.
|
|
// This is tracked in <rdar://problem/6062711>.
|
|
// See also http://llvm.org/bugs/show_bug.cgi?id=3714.
|
|
const RetainSummary *NoTrackYet = getPersistentSummary(RetEffect::MakeNoRet(),
|
|
StopTracking,
|
|
StopTracking);
|
|
|
|
addClassMethSummary("NSWindow", "alloc", NoTrackYet);
|
|
|
|
// For NSPanel (which subclasses NSWindow), allocated objects are not
|
|
// self-owned.
|
|
// FIXME: For now we don't track NSPanels. object for the same reason
|
|
// as for NSWindow objects.
|
|
addClassMethSummary("NSPanel", "alloc", NoTrackYet);
|
|
|
|
// For NSNull, objects returned by +null are singletons that ignore
|
|
// retain/release semantics. Just don't track them.
|
|
// <rdar://problem/12858915>
|
|
addClassMethSummary("NSNull", "null", NoTrackYet);
|
|
|
|
// Don't track allocated autorelease pools, as it is okay to prematurely
|
|
// exit a method.
|
|
addClassMethSummary("NSAutoreleasePool", "alloc", NoTrackYet);
|
|
addClassMethSummary("NSAutoreleasePool", "allocWithZone", NoTrackYet, false);
|
|
addClassMethSummary("NSAutoreleasePool", "new", NoTrackYet);
|
|
|
|
// Create summaries QCRenderer/QCView -createSnapShotImageOfType:
|
|
addInstMethSummary("QCRenderer", AllocSumm,
|
|
"createSnapshotImageOfType", NULL);
|
|
addInstMethSummary("QCView", AllocSumm,
|
|
"createSnapshotImageOfType", NULL);
|
|
|
|
// Create summaries for CIContext, 'createCGImage' and
|
|
// 'createCGLayerWithSize'. These objects are CF objects, and are not
|
|
// automatically garbage collected.
|
|
addInstMethSummary("CIContext", CFAllocSumm,
|
|
"createCGImage", "fromRect", NULL);
|
|
addInstMethSummary("CIContext", CFAllocSumm,
|
|
"createCGImage", "fromRect", "format", "colorSpace", NULL);
|
|
addInstMethSummary("CIContext", CFAllocSumm, "createCGLayerWithSize",
|
|
"info", NULL);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Error reporting.
|
|
//===----------------------------------------------------------------------===//
|
|
namespace {
|
|
typedef llvm::DenseMap<const ExplodedNode *, const RetainSummary *>
|
|
SummaryLogTy;
|
|
|
|
//===-------------===//
|
|
// Bug Descriptions. //
|
|
//===-------------===//
|
|
|
|
class CFRefBug : public BugType {
|
|
protected:
|
|
CFRefBug(const CheckerBase *checker, StringRef name)
|
|
: BugType(checker, name, categories::MemoryCoreFoundationObjectiveC) {}
|
|
|
|
public:
|
|
|
|
// FIXME: Eventually remove.
|
|
virtual const char *getDescription() const = 0;
|
|
|
|
virtual bool isLeak() const { return false; }
|
|
};
|
|
|
|
class UseAfterRelease : public CFRefBug {
|
|
public:
|
|
UseAfterRelease(const CheckerBase *checker)
|
|
: CFRefBug(checker, "Use-after-release") {}
|
|
|
|
const char *getDescription() const override {
|
|
return "Reference-counted object is used after it is released";
|
|
}
|
|
};
|
|
|
|
class BadRelease : public CFRefBug {
|
|
public:
|
|
BadRelease(const CheckerBase *checker) : CFRefBug(checker, "Bad release") {}
|
|
|
|
const char *getDescription() const override {
|
|
return "Incorrect decrement of the reference count of an object that is "
|
|
"not owned at this point by the caller";
|
|
}
|
|
};
|
|
|
|
class DeallocGC : public CFRefBug {
|
|
public:
|
|
DeallocGC(const CheckerBase *checker)
|
|
: CFRefBug(checker, "-dealloc called while using garbage collection") {}
|
|
|
|
const char *getDescription() const override {
|
|
return "-dealloc called while using garbage collection";
|
|
}
|
|
};
|
|
|
|
class DeallocNotOwned : public CFRefBug {
|
|
public:
|
|
DeallocNotOwned(const CheckerBase *checker)
|
|
: CFRefBug(checker, "-dealloc sent to non-exclusively owned object") {}
|
|
|
|
const char *getDescription() const override {
|
|
return "-dealloc sent to object that may be referenced elsewhere";
|
|
}
|
|
};
|
|
|
|
class OverAutorelease : public CFRefBug {
|
|
public:
|
|
OverAutorelease(const CheckerBase *checker)
|
|
: CFRefBug(checker, "Object autoreleased too many times") {}
|
|
|
|
const char *getDescription() const override {
|
|
return "Object autoreleased too many times";
|
|
}
|
|
};
|
|
|
|
class ReturnedNotOwnedForOwned : public CFRefBug {
|
|
public:
|
|
ReturnedNotOwnedForOwned(const CheckerBase *checker)
|
|
: CFRefBug(checker, "Method should return an owned object") {}
|
|
|
|
const char *getDescription() const override {
|
|
return "Object with a +0 retain count returned to caller where a +1 "
|
|
"(owning) retain count is expected";
|
|
}
|
|
};
|
|
|
|
class Leak : public CFRefBug {
|
|
public:
|
|
Leak(const CheckerBase *checker, StringRef name) : CFRefBug(checker, name) {
|
|
// Leaks should not be reported if they are post-dominated by a sink.
|
|
setSuppressOnSink(true);
|
|
}
|
|
|
|
const char *getDescription() const override { return ""; }
|
|
|
|
bool isLeak() const override { return true; }
|
|
};
|
|
|
|
//===---------===//
|
|
// Bug Reports. //
|
|
//===---------===//
|
|
|
|
class CFRefReportVisitor : public BugReporterVisitorImpl<CFRefReportVisitor> {
|
|
protected:
|
|
SymbolRef Sym;
|
|
const SummaryLogTy &SummaryLog;
|
|
bool GCEnabled;
|
|
|
|
public:
|
|
CFRefReportVisitor(SymbolRef sym, bool gcEnabled, const SummaryLogTy &log)
|
|
: Sym(sym), SummaryLog(log), GCEnabled(gcEnabled) {}
|
|
|
|
void Profile(llvm::FoldingSetNodeID &ID) const override {
|
|
static int x = 0;
|
|
ID.AddPointer(&x);
|
|
ID.AddPointer(Sym);
|
|
}
|
|
|
|
PathDiagnosticPiece *VisitNode(const ExplodedNode *N,
|
|
const ExplodedNode *PrevN,
|
|
BugReporterContext &BRC,
|
|
BugReport &BR) override;
|
|
|
|
PathDiagnosticPiece *getEndPath(BugReporterContext &BRC,
|
|
const ExplodedNode *N,
|
|
BugReport &BR) override;
|
|
};
|
|
|
|
class CFRefLeakReportVisitor : public CFRefReportVisitor {
|
|
public:
|
|
CFRefLeakReportVisitor(SymbolRef sym, bool GCEnabled,
|
|
const SummaryLogTy &log)
|
|
: CFRefReportVisitor(sym, GCEnabled, log) {}
|
|
|
|
PathDiagnosticPiece *getEndPath(BugReporterContext &BRC,
|
|
const ExplodedNode *N,
|
|
BugReport &BR) override;
|
|
|
|
BugReporterVisitor *clone() const override {
|
|
// The curiously-recurring template pattern only works for one level of
|
|
// subclassing. Rather than make a new template base for
|
|
// CFRefReportVisitor, we simply override clone() to do the right thing.
|
|
// This could be trouble someday if BugReporterVisitorImpl is ever
|
|
// used for something else besides a convenient implementation of clone().
|
|
return new CFRefLeakReportVisitor(*this);
|
|
}
|
|
};
|
|
|
|
class CFRefReport : public BugReport {
|
|
void addGCModeDescription(const LangOptions &LOpts, bool GCEnabled);
|
|
|
|
public:
|
|
CFRefReport(CFRefBug &D, const LangOptions &LOpts, bool GCEnabled,
|
|
const SummaryLogTy &Log, ExplodedNode *n, SymbolRef sym,
|
|
bool registerVisitor = true)
|
|
: BugReport(D, D.getDescription(), n) {
|
|
if (registerVisitor)
|
|
addVisitor(new CFRefReportVisitor(sym, GCEnabled, Log));
|
|
addGCModeDescription(LOpts, GCEnabled);
|
|
}
|
|
|
|
CFRefReport(CFRefBug &D, const LangOptions &LOpts, bool GCEnabled,
|
|
const SummaryLogTy &Log, ExplodedNode *n, SymbolRef sym,
|
|
StringRef endText)
|
|
: BugReport(D, D.getDescription(), endText, n) {
|
|
addVisitor(new CFRefReportVisitor(sym, GCEnabled, Log));
|
|
addGCModeDescription(LOpts, GCEnabled);
|
|
}
|
|
|
|
std::pair<ranges_iterator, ranges_iterator> getRanges() override {
|
|
const CFRefBug& BugTy = static_cast<CFRefBug&>(getBugType());
|
|
if (!BugTy.isLeak())
|
|
return BugReport::getRanges();
|
|
else
|
|
return std::make_pair(ranges_iterator(), ranges_iterator());
|
|
}
|
|
};
|
|
|
|
class CFRefLeakReport : public CFRefReport {
|
|
const MemRegion* AllocBinding;
|
|
public:
|
|
CFRefLeakReport(CFRefBug &D, const LangOptions &LOpts, bool GCEnabled,
|
|
const SummaryLogTy &Log, ExplodedNode *n, SymbolRef sym,
|
|
CheckerContext &Ctx,
|
|
bool IncludeAllocationLine);
|
|
|
|
PathDiagnosticLocation getLocation(const SourceManager &SM) const override {
|
|
assert(Location.isValid());
|
|
return Location;
|
|
}
|
|
};
|
|
} // end anonymous namespace
|
|
|
|
void CFRefReport::addGCModeDescription(const LangOptions &LOpts,
|
|
bool GCEnabled) {
|
|
const char *GCModeDescription = 0;
|
|
|
|
switch (LOpts.getGC()) {
|
|
case LangOptions::GCOnly:
|
|
assert(GCEnabled);
|
|
GCModeDescription = "Code is compiled to only use garbage collection";
|
|
break;
|
|
|
|
case LangOptions::NonGC:
|
|
assert(!GCEnabled);
|
|
GCModeDescription = "Code is compiled to use reference counts";
|
|
break;
|
|
|
|
case LangOptions::HybridGC:
|
|
if (GCEnabled) {
|
|
GCModeDescription = "Code is compiled to use either garbage collection "
|
|
"(GC) or reference counts (non-GC). The bug occurs "
|
|
"with GC enabled";
|
|
break;
|
|
} else {
|
|
GCModeDescription = "Code is compiled to use either garbage collection "
|
|
"(GC) or reference counts (non-GC). The bug occurs "
|
|
"in non-GC mode";
|
|
break;
|
|
}
|
|
}
|
|
|
|
assert(GCModeDescription && "invalid/unknown GC mode");
|
|
addExtraText(GCModeDescription);
|
|
}
|
|
|
|
static bool isNumericLiteralExpression(const Expr *E) {
|
|
// FIXME: This set of cases was copied from SemaExprObjC.
|
|
return isa<IntegerLiteral>(E) ||
|
|
isa<CharacterLiteral>(E) ||
|
|
isa<FloatingLiteral>(E) ||
|
|
isa<ObjCBoolLiteralExpr>(E) ||
|
|
isa<CXXBoolLiteralExpr>(E);
|
|
}
|
|
|
|
PathDiagnosticPiece *CFRefReportVisitor::VisitNode(const ExplodedNode *N,
|
|
const ExplodedNode *PrevN,
|
|
BugReporterContext &BRC,
|
|
BugReport &BR) {
|
|
// FIXME: We will eventually need to handle non-statement-based events
|
|
// (__attribute__((cleanup))).
|
|
if (!N->getLocation().getAs<StmtPoint>())
|
|
return NULL;
|
|
|
|
// Check if the type state has changed.
|
|
ProgramStateRef PrevSt = PrevN->getState();
|
|
ProgramStateRef CurrSt = N->getState();
|
|
const LocationContext *LCtx = N->getLocationContext();
|
|
|
|
const RefVal* CurrT = getRefBinding(CurrSt, Sym);
|
|
if (!CurrT) return NULL;
|
|
|
|
const RefVal &CurrV = *CurrT;
|
|
const RefVal *PrevT = getRefBinding(PrevSt, Sym);
|
|
|
|
// Create a string buffer to constain all the useful things we want
|
|
// to tell the user.
|
|
std::string sbuf;
|
|
llvm::raw_string_ostream os(sbuf);
|
|
|
|
// This is the allocation site since the previous node had no bindings
|
|
// for this symbol.
|
|
if (!PrevT) {
|
|
const Stmt *S = N->getLocation().castAs<StmtPoint>().getStmt();
|
|
|
|
if (isa<ObjCArrayLiteral>(S)) {
|
|
os << "NSArray literal is an object with a +0 retain count";
|
|
}
|
|
else if (isa<ObjCDictionaryLiteral>(S)) {
|
|
os << "NSDictionary literal is an object with a +0 retain count";
|
|
}
|
|
else if (const ObjCBoxedExpr *BL = dyn_cast<ObjCBoxedExpr>(S)) {
|
|
if (isNumericLiteralExpression(BL->getSubExpr()))
|
|
os << "NSNumber literal is an object with a +0 retain count";
|
|
else {
|
|
const ObjCInterfaceDecl *BoxClass = 0;
|
|
if (const ObjCMethodDecl *Method = BL->getBoxingMethod())
|
|
BoxClass = Method->getClassInterface();
|
|
|
|
// We should always be able to find the boxing class interface,
|
|
// but consider this future-proofing.
|
|
if (BoxClass)
|
|
os << *BoxClass << " b";
|
|
else
|
|
os << "B";
|
|
|
|
os << "oxed expression produces an object with a +0 retain count";
|
|
}
|
|
}
|
|
else {
|
|
if (const CallExpr *CE = dyn_cast<CallExpr>(S)) {
|
|
// Get the name of the callee (if it is available).
|
|
SVal X = CurrSt->getSValAsScalarOrLoc(CE->getCallee(), LCtx);
|
|
if (const FunctionDecl *FD = X.getAsFunctionDecl())
|
|
os << "Call to function '" << *FD << '\'';
|
|
else
|
|
os << "function call";
|
|
}
|
|
else {
|
|
assert(isa<ObjCMessageExpr>(S));
|
|
CallEventManager &Mgr = CurrSt->getStateManager().getCallEventManager();
|
|
CallEventRef<ObjCMethodCall> Call
|
|
= Mgr.getObjCMethodCall(cast<ObjCMessageExpr>(S), CurrSt, LCtx);
|
|
|
|
switch (Call->getMessageKind()) {
|
|
case OCM_Message:
|
|
os << "Method";
|
|
break;
|
|
case OCM_PropertyAccess:
|
|
os << "Property";
|
|
break;
|
|
case OCM_Subscript:
|
|
os << "Subscript";
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (CurrV.getObjKind() == RetEffect::CF) {
|
|
os << " returns a Core Foundation object with a ";
|
|
}
|
|
else {
|
|
assert (CurrV.getObjKind() == RetEffect::ObjC);
|
|
os << " returns an Objective-C object with a ";
|
|
}
|
|
|
|
if (CurrV.isOwned()) {
|
|
os << "+1 retain count";
|
|
|
|
if (GCEnabled) {
|
|
assert(CurrV.getObjKind() == RetEffect::CF);
|
|
os << ". "
|
|
"Core Foundation objects are not automatically garbage collected.";
|
|
}
|
|
}
|
|
else {
|
|
assert (CurrV.isNotOwned());
|
|
os << "+0 retain count";
|
|
}
|
|
}
|
|
|
|
PathDiagnosticLocation Pos(S, BRC.getSourceManager(),
|
|
N->getLocationContext());
|
|
return new PathDiagnosticEventPiece(Pos, os.str());
|
|
}
|
|
|
|
// Gather up the effects that were performed on the object at this
|
|
// program point
|
|
SmallVector<ArgEffect, 2> AEffects;
|
|
|
|
const ExplodedNode *OrigNode = BRC.getNodeResolver().getOriginalNode(N);
|
|
if (const RetainSummary *Summ = SummaryLog.lookup(OrigNode)) {
|
|
// We only have summaries attached to nodes after evaluating CallExpr and
|
|
// ObjCMessageExprs.
|
|
const Stmt *S = N->getLocation().castAs<StmtPoint>().getStmt();
|
|
|
|
if (const CallExpr *CE = dyn_cast<CallExpr>(S)) {
|
|
// Iterate through the parameter expressions and see if the symbol
|
|
// was ever passed as an argument.
|
|
unsigned i = 0;
|
|
|
|
for (CallExpr::const_arg_iterator AI=CE->arg_begin(), AE=CE->arg_end();
|
|
AI!=AE; ++AI, ++i) {
|
|
|
|
// Retrieve the value of the argument. Is it the symbol
|
|
// we are interested in?
|
|
if (CurrSt->getSValAsScalarOrLoc(*AI, LCtx).getAsLocSymbol() != Sym)
|
|
continue;
|
|
|
|
// We have an argument. Get the effect!
|
|
AEffects.push_back(Summ->getArg(i));
|
|
}
|
|
}
|
|
else if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(S)) {
|
|
if (const Expr *receiver = ME->getInstanceReceiver())
|
|
if (CurrSt->getSValAsScalarOrLoc(receiver, LCtx)
|
|
.getAsLocSymbol() == Sym) {
|
|
// The symbol we are tracking is the receiver.
|
|
AEffects.push_back(Summ->getReceiverEffect());
|
|
}
|
|
}
|
|
}
|
|
|
|
do {
|
|
// Get the previous type state.
|
|
RefVal PrevV = *PrevT;
|
|
|
|
// Specially handle -dealloc.
|
|
if (!GCEnabled && std::find(AEffects.begin(), AEffects.end(), Dealloc) !=
|
|
AEffects.end()) {
|
|
// Determine if the object's reference count was pushed to zero.
|
|
assert(!PrevV.hasSameState(CurrV) && "The state should have changed.");
|
|
// We may not have transitioned to 'release' if we hit an error.
|
|
// This case is handled elsewhere.
|
|
if (CurrV.getKind() == RefVal::Released) {
|
|
assert(CurrV.getCombinedCounts() == 0);
|
|
os << "Object released by directly sending the '-dealloc' message";
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Specially handle CFMakeCollectable and friends.
|
|
if (std::find(AEffects.begin(), AEffects.end(), MakeCollectable) !=
|
|
AEffects.end()) {
|
|
// Get the name of the function.
|
|
const Stmt *S = N->getLocation().castAs<StmtPoint>().getStmt();
|
|
SVal X =
|
|
CurrSt->getSValAsScalarOrLoc(cast<CallExpr>(S)->getCallee(), LCtx);
|
|
const FunctionDecl *FD = X.getAsFunctionDecl();
|
|
|
|
if (GCEnabled) {
|
|
// Determine if the object's reference count was pushed to zero.
|
|
assert(!PrevV.hasSameState(CurrV) && "The state should have changed.");
|
|
|
|
os << "In GC mode a call to '" << *FD
|
|
<< "' decrements an object's retain count and registers the "
|
|
"object with the garbage collector. ";
|
|
|
|
if (CurrV.getKind() == RefVal::Released) {
|
|
assert(CurrV.getCount() == 0);
|
|
os << "Since it now has a 0 retain count the object can be "
|
|
"automatically collected by the garbage collector.";
|
|
}
|
|
else
|
|
os << "An object must have a 0 retain count to be garbage collected. "
|
|
"After this call its retain count is +" << CurrV.getCount()
|
|
<< '.';
|
|
}
|
|
else
|
|
os << "When GC is not enabled a call to '" << *FD
|
|
<< "' has no effect on its argument.";
|
|
|
|
// Nothing more to say.
|
|
break;
|
|
}
|
|
|
|
// Determine if the typestate has changed.
|
|
if (!PrevV.hasSameState(CurrV))
|
|
switch (CurrV.getKind()) {
|
|
case RefVal::Owned:
|
|
case RefVal::NotOwned:
|
|
|
|
if (PrevV.getCount() == CurrV.getCount()) {
|
|
// Did an autorelease message get sent?
|
|
if (PrevV.getAutoreleaseCount() == CurrV.getAutoreleaseCount())
|
|
return 0;
|
|
|
|
assert(PrevV.getAutoreleaseCount() < CurrV.getAutoreleaseCount());
|
|
os << "Object autoreleased";
|
|
break;
|
|
}
|
|
|
|
if (PrevV.getCount() > CurrV.getCount())
|
|
os << "Reference count decremented.";
|
|
else
|
|
os << "Reference count incremented.";
|
|
|
|
if (unsigned Count = CurrV.getCount())
|
|
os << " The object now has a +" << Count << " retain count.";
|
|
|
|
if (PrevV.getKind() == RefVal::Released) {
|
|
assert(GCEnabled && CurrV.getCount() > 0);
|
|
os << " The object is not eligible for garbage collection until "
|
|
"the retain count reaches 0 again.";
|
|
}
|
|
|
|
break;
|
|
|
|
case RefVal::Released:
|
|
os << "Object released.";
|
|
break;
|
|
|
|
case RefVal::ReturnedOwned:
|
|
// Autoreleases can be applied after marking a node ReturnedOwned.
|
|
if (CurrV.getAutoreleaseCount())
|
|
return NULL;
|
|
|
|
os << "Object returned to caller as an owning reference (single "
|
|
"retain count transferred to caller)";
|
|
break;
|
|
|
|
case RefVal::ReturnedNotOwned:
|
|
os << "Object returned to caller with a +0 retain count";
|
|
break;
|
|
|
|
default:
|
|
return NULL;
|
|
}
|
|
|
|
// Emit any remaining diagnostics for the argument effects (if any).
|
|
for (SmallVectorImpl<ArgEffect>::iterator I=AEffects.begin(),
|
|
E=AEffects.end(); I != E; ++I) {
|
|
|
|
// A bunch of things have alternate behavior under GC.
|
|
if (GCEnabled)
|
|
switch (*I) {
|
|
default: break;
|
|
case Autorelease:
|
|
os << "In GC mode an 'autorelease' has no effect.";
|
|
continue;
|
|
case IncRefMsg:
|
|
os << "In GC mode the 'retain' message has no effect.";
|
|
continue;
|
|
case DecRefMsg:
|
|
os << "In GC mode the 'release' message has no effect.";
|
|
continue;
|
|
}
|
|
}
|
|
} while (0);
|
|
|
|
if (os.str().empty())
|
|
return 0; // We have nothing to say!
|
|
|
|
const Stmt *S = N->getLocation().castAs<StmtPoint>().getStmt();
|
|
PathDiagnosticLocation Pos(S, BRC.getSourceManager(),
|
|
N->getLocationContext());
|
|
PathDiagnosticPiece *P = new PathDiagnosticEventPiece(Pos, os.str());
|
|
|
|
// Add the range by scanning the children of the statement for any bindings
|
|
// to Sym.
|
|
for (Stmt::const_child_iterator I = S->child_begin(), E = S->child_end();
|
|
I!=E; ++I)
|
|
if (const Expr *Exp = dyn_cast_or_null<Expr>(*I))
|
|
if (CurrSt->getSValAsScalarOrLoc(Exp, LCtx).getAsLocSymbol() == Sym) {
|
|
P->addRange(Exp->getSourceRange());
|
|
break;
|
|
}
|
|
|
|
return P;
|
|
}
|
|
|
|
// Find the first node in the current function context that referred to the
|
|
// tracked symbol and the memory location that value was stored to. Note, the
|
|
// value is only reported if the allocation occurred in the same function as
|
|
// the leak. The function can also return a location context, which should be
|
|
// treated as interesting.
|
|
struct AllocationInfo {
|
|
const ExplodedNode* N;
|
|
const MemRegion *R;
|
|
const LocationContext *InterestingMethodContext;
|
|
AllocationInfo(const ExplodedNode *InN,
|
|
const MemRegion *InR,
|
|
const LocationContext *InInterestingMethodContext) :
|
|
N(InN), R(InR), InterestingMethodContext(InInterestingMethodContext) {}
|
|
};
|
|
|
|
static AllocationInfo
|
|
GetAllocationSite(ProgramStateManager& StateMgr, const ExplodedNode *N,
|
|
SymbolRef Sym) {
|
|
const ExplodedNode *AllocationNode = N;
|
|
const ExplodedNode *AllocationNodeInCurrentContext = N;
|
|
const MemRegion* FirstBinding = 0;
|
|
const LocationContext *LeakContext = N->getLocationContext();
|
|
|
|
// The location context of the init method called on the leaked object, if
|
|
// available.
|
|
const LocationContext *InitMethodContext = 0;
|
|
|
|
while (N) {
|
|
ProgramStateRef St = N->getState();
|
|
const LocationContext *NContext = N->getLocationContext();
|
|
|
|
if (!getRefBinding(St, Sym))
|
|
break;
|
|
|
|
StoreManager::FindUniqueBinding FB(Sym);
|
|
StateMgr.iterBindings(St, FB);
|
|
|
|
if (FB) {
|
|
const MemRegion *R = FB.getRegion();
|
|
const VarRegion *VR = R->getBaseRegion()->getAs<VarRegion>();
|
|
// Do not show local variables belonging to a function other than
|
|
// where the error is reported.
|
|
if (!VR || VR->getStackFrame() == LeakContext->getCurrentStackFrame())
|
|
FirstBinding = R;
|
|
}
|
|
|
|
// AllocationNode is the last node in which the symbol was tracked.
|
|
AllocationNode = N;
|
|
|
|
// AllocationNodeInCurrentContext, is the last node in the current context
|
|
// in which the symbol was tracked.
|
|
if (NContext == LeakContext)
|
|
AllocationNodeInCurrentContext = N;
|
|
|
|
// Find the last init that was called on the given symbol and store the
|
|
// init method's location context.
|
|
if (!InitMethodContext)
|
|
if (Optional<CallEnter> CEP = N->getLocation().getAs<CallEnter>()) {
|
|
const Stmt *CE = CEP->getCallExpr();
|
|
if (const ObjCMessageExpr *ME = dyn_cast_or_null<ObjCMessageExpr>(CE)) {
|
|
const Stmt *RecExpr = ME->getInstanceReceiver();
|
|
if (RecExpr) {
|
|
SVal RecV = St->getSVal(RecExpr, NContext);
|
|
if (ME->getMethodFamily() == OMF_init && RecV.getAsSymbol() == Sym)
|
|
InitMethodContext = CEP->getCalleeContext();
|
|
}
|
|
}
|
|
}
|
|
|
|
N = N->pred_empty() ? NULL : *(N->pred_begin());
|
|
}
|
|
|
|
// If we are reporting a leak of the object that was allocated with alloc,
|
|
// mark its init method as interesting.
|
|
const LocationContext *InterestingMethodContext = 0;
|
|
if (InitMethodContext) {
|
|
const ProgramPoint AllocPP = AllocationNode->getLocation();
|
|
if (Optional<StmtPoint> SP = AllocPP.getAs<StmtPoint>())
|
|
if (const ObjCMessageExpr *ME = SP->getStmtAs<ObjCMessageExpr>())
|
|
if (ME->getMethodFamily() == OMF_alloc)
|
|
InterestingMethodContext = InitMethodContext;
|
|
}
|
|
|
|
// If allocation happened in a function different from the leak node context,
|
|
// do not report the binding.
|
|
assert(N && "Could not find allocation node");
|
|
if (N->getLocationContext() != LeakContext) {
|
|
FirstBinding = 0;
|
|
}
|
|
|
|
return AllocationInfo(AllocationNodeInCurrentContext,
|
|
FirstBinding,
|
|
InterestingMethodContext);
|
|
}
|
|
|
|
PathDiagnosticPiece*
|
|
CFRefReportVisitor::getEndPath(BugReporterContext &BRC,
|
|
const ExplodedNode *EndN,
|
|
BugReport &BR) {
|
|
BR.markInteresting(Sym);
|
|
return BugReporterVisitor::getDefaultEndPath(BRC, EndN, BR);
|
|
}
|
|
|
|
PathDiagnosticPiece*
|
|
CFRefLeakReportVisitor::getEndPath(BugReporterContext &BRC,
|
|
const ExplodedNode *EndN,
|
|
BugReport &BR) {
|
|
|
|
// Tell the BugReporterContext to report cases when the tracked symbol is
|
|
// assigned to different variables, etc.
|
|
BR.markInteresting(Sym);
|
|
|
|
// We are reporting a leak. Walk up the graph to get to the first node where
|
|
// the symbol appeared, and also get the first VarDecl that tracked object
|
|
// is stored to.
|
|
AllocationInfo AllocI =
|
|
GetAllocationSite(BRC.getStateManager(), EndN, Sym);
|
|
|
|
const MemRegion* FirstBinding = AllocI.R;
|
|
BR.markInteresting(AllocI.InterestingMethodContext);
|
|
|
|
SourceManager& SM = BRC.getSourceManager();
|
|
|
|
// Compute an actual location for the leak. Sometimes a leak doesn't
|
|
// occur at an actual statement (e.g., transition between blocks; end
|
|
// of function) so we need to walk the graph and compute a real location.
|
|
const ExplodedNode *LeakN = EndN;
|
|
PathDiagnosticLocation L = PathDiagnosticLocation::createEndOfPath(LeakN, SM);
|
|
|
|
std::string sbuf;
|
|
llvm::raw_string_ostream os(sbuf);
|
|
|
|
os << "Object leaked: ";
|
|
|
|
if (FirstBinding) {
|
|
os << "object allocated and stored into '"
|
|
<< FirstBinding->getString() << '\'';
|
|
}
|
|
else
|
|
os << "allocated object";
|
|
|
|
// Get the retain count.
|
|
const RefVal* RV = getRefBinding(EndN->getState(), Sym);
|
|
assert(RV);
|
|
|
|
if (RV->getKind() == RefVal::ErrorLeakReturned) {
|
|
// FIXME: Per comments in rdar://6320065, "create" only applies to CF
|
|
// objects. Only "copy", "alloc", "retain" and "new" transfer ownership
|
|
// to the caller for NS objects.
|
|
const Decl *D = &EndN->getCodeDecl();
|
|
|
|
os << (isa<ObjCMethodDecl>(D) ? " is returned from a method "
|
|
: " is returned from a function ");
|
|
|
|
if (D->hasAttr<CFReturnsNotRetainedAttr>())
|
|
os << "that is annotated as CF_RETURNS_NOT_RETAINED";
|
|
else if (D->hasAttr<NSReturnsNotRetainedAttr>())
|
|
os << "that is annotated as NS_RETURNS_NOT_RETAINED";
|
|
else {
|
|
if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
|
|
os << "whose name ('" << MD->getSelector().getAsString()
|
|
<< "') does not start with 'copy', 'mutableCopy', 'alloc' or 'new'."
|
|
" This violates the naming convention rules"
|
|
" given in the Memory Management Guide for Cocoa";
|
|
}
|
|
else {
|
|
const FunctionDecl *FD = cast<FunctionDecl>(D);
|
|
os << "whose name ('" << *FD
|
|
<< "') does not contain 'Copy' or 'Create'. This violates the naming"
|
|
" convention rules given in the Memory Management Guide for Core"
|
|
" Foundation";
|
|
}
|
|
}
|
|
}
|
|
else if (RV->getKind() == RefVal::ErrorGCLeakReturned) {
|
|
const ObjCMethodDecl &MD = cast<ObjCMethodDecl>(EndN->getCodeDecl());
|
|
os << " and returned from method '" << MD.getSelector().getAsString()
|
|
<< "' is potentially leaked when using garbage collection. Callers "
|
|
"of this method do not expect a returned object with a +1 retain "
|
|
"count since they expect the object to be managed by the garbage "
|
|
"collector";
|
|
}
|
|
else
|
|
os << " is not referenced later in this execution path and has a retain "
|
|
"count of +" << RV->getCount();
|
|
|
|
return new PathDiagnosticEventPiece(L, os.str());
|
|
}
|
|
|
|
CFRefLeakReport::CFRefLeakReport(CFRefBug &D, const LangOptions &LOpts,
|
|
bool GCEnabled, const SummaryLogTy &Log,
|
|
ExplodedNode *n, SymbolRef sym,
|
|
CheckerContext &Ctx,
|
|
bool IncludeAllocationLine)
|
|
: CFRefReport(D, LOpts, GCEnabled, Log, n, sym, false) {
|
|
|
|
// Most bug reports are cached at the location where they occurred.
|
|
// With leaks, we want to unique them by the location where they were
|
|
// allocated, and only report a single path. To do this, we need to find
|
|
// the allocation site of a piece of tracked memory, which we do via a
|
|
// call to GetAllocationSite. This will walk the ExplodedGraph backwards.
|
|
// Note that this is *not* the trimmed graph; we are guaranteed, however,
|
|
// that all ancestor nodes that represent the allocation site have the
|
|
// same SourceLocation.
|
|
const ExplodedNode *AllocNode = 0;
|
|
|
|
const SourceManager& SMgr = Ctx.getSourceManager();
|
|
|
|
AllocationInfo AllocI =
|
|
GetAllocationSite(Ctx.getStateManager(), getErrorNode(), sym);
|
|
|
|
AllocNode = AllocI.N;
|
|
AllocBinding = AllocI.R;
|
|
markInteresting(AllocI.InterestingMethodContext);
|
|
|
|
// Get the SourceLocation for the allocation site.
|
|
// FIXME: This will crash the analyzer if an allocation comes from an
|
|
// implicit call. (Currently there are no such allocations in Cocoa, though.)
|
|
const Stmt *AllocStmt;
|
|
ProgramPoint P = AllocNode->getLocation();
|
|
if (Optional<CallExitEnd> Exit = P.getAs<CallExitEnd>())
|
|
AllocStmt = Exit->getCalleeContext()->getCallSite();
|
|
else
|
|
AllocStmt = P.castAs<PostStmt>().getStmt();
|
|
assert(AllocStmt && "All allocations must come from explicit calls");
|
|
|
|
PathDiagnosticLocation AllocLocation =
|
|
PathDiagnosticLocation::createBegin(AllocStmt, SMgr,
|
|
AllocNode->getLocationContext());
|
|
Location = AllocLocation;
|
|
|
|
// Set uniqieing info, which will be used for unique the bug reports. The
|
|
// leaks should be uniqued on the allocation site.
|
|
UniqueingLocation = AllocLocation;
|
|
UniqueingDecl = AllocNode->getLocationContext()->getDecl();
|
|
|
|
// Fill in the description of the bug.
|
|
Description.clear();
|
|
llvm::raw_string_ostream os(Description);
|
|
os << "Potential leak ";
|
|
if (GCEnabled)
|
|
os << "(when using garbage collection) ";
|
|
os << "of an object";
|
|
|
|
if (AllocBinding) {
|
|
os << " stored into '" << AllocBinding->getString() << '\'';
|
|
if (IncludeAllocationLine) {
|
|
FullSourceLoc SL(AllocStmt->getLocStart(), Ctx.getSourceManager());
|
|
os << " (allocated on line " << SL.getSpellingLineNumber() << ")";
|
|
}
|
|
}
|
|
|
|
addVisitor(new CFRefLeakReportVisitor(sym, GCEnabled, Log));
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Main checker logic.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace {
|
|
class RetainCountChecker
|
|
: public Checker< check::Bind,
|
|
check::DeadSymbols,
|
|
check::EndAnalysis,
|
|
check::EndFunction,
|
|
check::PostStmt<BlockExpr>,
|
|
check::PostStmt<CastExpr>,
|
|
check::PostStmt<ObjCArrayLiteral>,
|
|
check::PostStmt<ObjCDictionaryLiteral>,
|
|
check::PostStmt<ObjCBoxedExpr>,
|
|
check::PostStmt<ObjCIvarRefExpr>,
|
|
check::PostCall,
|
|
check::PreStmt<ReturnStmt>,
|
|
check::RegionChanges,
|
|
eval::Assume,
|
|
eval::Call > {
|
|
mutable std::unique_ptr<CFRefBug> useAfterRelease, releaseNotOwned;
|
|
mutable std::unique_ptr<CFRefBug> deallocGC, deallocNotOwned;
|
|
mutable std::unique_ptr<CFRefBug> overAutorelease, returnNotOwnedForOwned;
|
|
mutable std::unique_ptr<CFRefBug> leakWithinFunction, leakAtReturn;
|
|
mutable std::unique_ptr<CFRefBug> leakWithinFunctionGC, leakAtReturnGC;
|
|
|
|
typedef llvm::DenseMap<SymbolRef, const CheckerProgramPointTag *> SymbolTagMap;
|
|
|
|
// This map is only used to ensure proper deletion of any allocated tags.
|
|
mutable SymbolTagMap DeadSymbolTags;
|
|
|
|
mutable std::unique_ptr<RetainSummaryManager> Summaries;
|
|
mutable std::unique_ptr<RetainSummaryManager> SummariesGC;
|
|
mutable SummaryLogTy SummaryLog;
|
|
mutable bool ShouldResetSummaryLog;
|
|
|
|
/// Optional setting to indicate if leak reports should include
|
|
/// the allocation line.
|
|
mutable bool IncludeAllocationLine;
|
|
|
|
public:
|
|
RetainCountChecker(AnalyzerOptions &AO)
|
|
: ShouldResetSummaryLog(false),
|
|
IncludeAllocationLine(shouldIncludeAllocationSiteInLeakDiagnostics(AO)) {}
|
|
|
|
virtual ~RetainCountChecker() {
|
|
DeleteContainerSeconds(DeadSymbolTags);
|
|
}
|
|
|
|
void checkEndAnalysis(ExplodedGraph &G, BugReporter &BR,
|
|
ExprEngine &Eng) const {
|
|
// FIXME: This is a hack to make sure the summary log gets cleared between
|
|
// analyses of different code bodies.
|
|
//
|
|
// Why is this necessary? Because a checker's lifetime is tied to a
|
|
// translation unit, but an ExplodedGraph's lifetime is just a code body.
|
|
// Once in a blue moon, a new ExplodedNode will have the same address as an
|
|
// old one with an associated summary, and the bug report visitor gets very
|
|
// confused. (To make things worse, the summary lifetime is currently also
|
|
// tied to a code body, so we get a crash instead of incorrect results.)
|
|
//
|
|
// Why is this a bad solution? Because if the lifetime of the ExplodedGraph
|
|
// changes, things will start going wrong again. Really the lifetime of this
|
|
// log needs to be tied to either the specific nodes in it or the entire
|
|
// ExplodedGraph, not to a specific part of the code being analyzed.
|
|
//
|
|
// (Also, having stateful local data means that the same checker can't be
|
|
// used from multiple threads, but a lot of checkers have incorrect
|
|
// assumptions about that anyway. So that wasn't a priority at the time of
|
|
// this fix.)
|
|
//
|
|
// This happens at the end of analysis, but bug reports are emitted /after/
|
|
// this point. So we can't just clear the summary log now. Instead, we mark
|
|
// that the next time we access the summary log, it should be cleared.
|
|
|
|
// If we never reset the summary log during /this/ code body analysis,
|
|
// there were no new summaries. There might still have been summaries from
|
|
// the /last/ analysis, so clear them out to make sure the bug report
|
|
// visitors don't get confused.
|
|
if (ShouldResetSummaryLog)
|
|
SummaryLog.clear();
|
|
|
|
ShouldResetSummaryLog = !SummaryLog.empty();
|
|
}
|
|
|
|
CFRefBug *getLeakWithinFunctionBug(const LangOptions &LOpts,
|
|
bool GCEnabled) const {
|
|
if (GCEnabled) {
|
|
if (!leakWithinFunctionGC)
|
|
leakWithinFunctionGC.reset(new Leak(this, "Leak of object when using "
|
|
"garbage collection"));
|
|
return leakWithinFunctionGC.get();
|
|
} else {
|
|
if (!leakWithinFunction) {
|
|
if (LOpts.getGC() == LangOptions::HybridGC) {
|
|
leakWithinFunction.reset(new Leak(this,
|
|
"Leak of object when not using "
|
|
"garbage collection (GC) in "
|
|
"dual GC/non-GC code"));
|
|
} else {
|
|
leakWithinFunction.reset(new Leak(this, "Leak"));
|
|
}
|
|
}
|
|
return leakWithinFunction.get();
|
|
}
|
|
}
|
|
|
|
CFRefBug *getLeakAtReturnBug(const LangOptions &LOpts, bool GCEnabled) const {
|
|
if (GCEnabled) {
|
|
if (!leakAtReturnGC)
|
|
leakAtReturnGC.reset(new Leak(this,
|
|
"Leak of returned object when using "
|
|
"garbage collection"));
|
|
return leakAtReturnGC.get();
|
|
} else {
|
|
if (!leakAtReturn) {
|
|
if (LOpts.getGC() == LangOptions::HybridGC) {
|
|
leakAtReturn.reset(new Leak(this,
|
|
"Leak of returned object when not using "
|
|
"garbage collection (GC) in dual "
|
|
"GC/non-GC code"));
|
|
} else {
|
|
leakAtReturn.reset(new Leak(this, "Leak of returned object"));
|
|
}
|
|
}
|
|
return leakAtReturn.get();
|
|
}
|
|
}
|
|
|
|
RetainSummaryManager &getSummaryManager(ASTContext &Ctx,
|
|
bool GCEnabled) const {
|
|
// FIXME: We don't support ARC being turned on and off during one analysis.
|
|
// (nor, for that matter, do we support changing ASTContexts)
|
|
bool ARCEnabled = (bool)Ctx.getLangOpts().ObjCAutoRefCount;
|
|
if (GCEnabled) {
|
|
if (!SummariesGC)
|
|
SummariesGC.reset(new RetainSummaryManager(Ctx, true, ARCEnabled));
|
|
else
|
|
assert(SummariesGC->isARCEnabled() == ARCEnabled);
|
|
return *SummariesGC;
|
|
} else {
|
|
if (!Summaries)
|
|
Summaries.reset(new RetainSummaryManager(Ctx, false, ARCEnabled));
|
|
else
|
|
assert(Summaries->isARCEnabled() == ARCEnabled);
|
|
return *Summaries;
|
|
}
|
|
}
|
|
|
|
RetainSummaryManager &getSummaryManager(CheckerContext &C) const {
|
|
return getSummaryManager(C.getASTContext(), C.isObjCGCEnabled());
|
|
}
|
|
|
|
void printState(raw_ostream &Out, ProgramStateRef State,
|
|
const char *NL, const char *Sep) const override;
|
|
|
|
void checkBind(SVal loc, SVal val, const Stmt *S, CheckerContext &C) const;
|
|
void checkPostStmt(const BlockExpr *BE, CheckerContext &C) const;
|
|
void checkPostStmt(const CastExpr *CE, CheckerContext &C) const;
|
|
|
|
void checkPostStmt(const ObjCArrayLiteral *AL, CheckerContext &C) const;
|
|
void checkPostStmt(const ObjCDictionaryLiteral *DL, CheckerContext &C) const;
|
|
void checkPostStmt(const ObjCBoxedExpr *BE, CheckerContext &C) const;
|
|
|
|
void checkPostStmt(const ObjCIvarRefExpr *IRE, CheckerContext &C) const;
|
|
|
|
void checkPostCall(const CallEvent &Call, CheckerContext &C) const;
|
|
|
|
void checkSummary(const RetainSummary &Summ, const CallEvent &Call,
|
|
CheckerContext &C) const;
|
|
|
|
void processSummaryOfInlined(const RetainSummary &Summ,
|
|
const CallEvent &Call,
|
|
CheckerContext &C) const;
|
|
|
|
bool evalCall(const CallExpr *CE, CheckerContext &C) const;
|
|
|
|
ProgramStateRef evalAssume(ProgramStateRef state, SVal Cond,
|
|
bool Assumption) const;
|
|
|
|
ProgramStateRef
|
|
checkRegionChanges(ProgramStateRef state,
|
|
const InvalidatedSymbols *invalidated,
|
|
ArrayRef<const MemRegion *> ExplicitRegions,
|
|
ArrayRef<const MemRegion *> Regions,
|
|
const CallEvent *Call) const;
|
|
|
|
bool wantsRegionChangeUpdate(ProgramStateRef state) const {
|
|
return true;
|
|
}
|
|
|
|
void checkPreStmt(const ReturnStmt *S, CheckerContext &C) const;
|
|
void checkReturnWithRetEffect(const ReturnStmt *S, CheckerContext &C,
|
|
ExplodedNode *Pred, RetEffect RE, RefVal X,
|
|
SymbolRef Sym, ProgramStateRef state) const;
|
|
|
|
void checkDeadSymbols(SymbolReaper &SymReaper, CheckerContext &C) const;
|
|
void checkEndFunction(CheckerContext &C) const;
|
|
|
|
ProgramStateRef updateSymbol(ProgramStateRef state, SymbolRef sym,
|
|
RefVal V, ArgEffect E, RefVal::Kind &hasErr,
|
|
CheckerContext &C) const;
|
|
|
|
void processNonLeakError(ProgramStateRef St, SourceRange ErrorRange,
|
|
RefVal::Kind ErrorKind, SymbolRef Sym,
|
|
CheckerContext &C) const;
|
|
|
|
void processObjCLiterals(CheckerContext &C, const Expr *Ex) const;
|
|
|
|
const ProgramPointTag *getDeadSymbolTag(SymbolRef sym) const;
|
|
|
|
ProgramStateRef handleSymbolDeath(ProgramStateRef state,
|
|
SymbolRef sid, RefVal V,
|
|
SmallVectorImpl<SymbolRef> &Leaked) const;
|
|
|
|
ProgramStateRef
|
|
handleAutoreleaseCounts(ProgramStateRef state, ExplodedNode *Pred,
|
|
const ProgramPointTag *Tag, CheckerContext &Ctx,
|
|
SymbolRef Sym, RefVal V) const;
|
|
|
|
ExplodedNode *processLeaks(ProgramStateRef state,
|
|
SmallVectorImpl<SymbolRef> &Leaked,
|
|
CheckerContext &Ctx,
|
|
ExplodedNode *Pred = 0) const;
|
|
};
|
|
} // end anonymous namespace
|
|
|
|
namespace {
|
|
class StopTrackingCallback : public SymbolVisitor {
|
|
ProgramStateRef state;
|
|
public:
|
|
StopTrackingCallback(ProgramStateRef st) : state(st) {}
|
|
ProgramStateRef getState() const { return state; }
|
|
|
|
bool VisitSymbol(SymbolRef sym) override {
|
|
state = state->remove<RefBindings>(sym);
|
|
return true;
|
|
}
|
|
};
|
|
} // end anonymous namespace
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Handle statements that may have an effect on refcounts.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void RetainCountChecker::checkPostStmt(const BlockExpr *BE,
|
|
CheckerContext &C) const {
|
|
|
|
// Scan the BlockDecRefExprs for any object the retain count checker
|
|
// may be tracking.
|
|
if (!BE->getBlockDecl()->hasCaptures())
|
|
return;
|
|
|
|
ProgramStateRef state = C.getState();
|
|
const BlockDataRegion *R =
|
|
cast<BlockDataRegion>(state->getSVal(BE,
|
|
C.getLocationContext()).getAsRegion());
|
|
|
|
BlockDataRegion::referenced_vars_iterator I = R->referenced_vars_begin(),
|
|
E = R->referenced_vars_end();
|
|
|
|
if (I == E)
|
|
return;
|
|
|
|
// FIXME: For now we invalidate the tracking of all symbols passed to blocks
|
|
// via captured variables, even though captured variables result in a copy
|
|
// and in implicit increment/decrement of a retain count.
|
|
SmallVector<const MemRegion*, 10> Regions;
|
|
const LocationContext *LC = C.getLocationContext();
|
|
MemRegionManager &MemMgr = C.getSValBuilder().getRegionManager();
|
|
|
|
for ( ; I != E; ++I) {
|
|
const VarRegion *VR = I.getCapturedRegion();
|
|
if (VR->getSuperRegion() == R) {
|
|
VR = MemMgr.getVarRegion(VR->getDecl(), LC);
|
|
}
|
|
Regions.push_back(VR);
|
|
}
|
|
|
|
state =
|
|
state->scanReachableSymbols<StopTrackingCallback>(Regions.data(),
|
|
Regions.data() + Regions.size()).getState();
|
|
C.addTransition(state);
|
|
}
|
|
|
|
void RetainCountChecker::checkPostStmt(const CastExpr *CE,
|
|
CheckerContext &C) const {
|
|
const ObjCBridgedCastExpr *BE = dyn_cast<ObjCBridgedCastExpr>(CE);
|
|
if (!BE)
|
|
return;
|
|
|
|
ArgEffect AE = IncRef;
|
|
|
|
switch (BE->getBridgeKind()) {
|
|
case clang::OBC_Bridge:
|
|
// Do nothing.
|
|
return;
|
|
case clang::OBC_BridgeRetained:
|
|
AE = IncRef;
|
|
break;
|
|
case clang::OBC_BridgeTransfer:
|
|
AE = DecRefBridgedTransferred;
|
|
break;
|
|
}
|
|
|
|
ProgramStateRef state = C.getState();
|
|
SymbolRef Sym = state->getSVal(CE, C.getLocationContext()).getAsLocSymbol();
|
|
if (!Sym)
|
|
return;
|
|
const RefVal* T = getRefBinding(state, Sym);
|
|
if (!T)
|
|
return;
|
|
|
|
RefVal::Kind hasErr = (RefVal::Kind) 0;
|
|
state = updateSymbol(state, Sym, *T, AE, hasErr, C);
|
|
|
|
if (hasErr) {
|
|
// FIXME: If we get an error during a bridge cast, should we report it?
|
|
// Should we assert that there is no error?
|
|
return;
|
|
}
|
|
|
|
C.addTransition(state);
|
|
}
|
|
|
|
void RetainCountChecker::processObjCLiterals(CheckerContext &C,
|
|
const Expr *Ex) const {
|
|
ProgramStateRef state = C.getState();
|
|
const ExplodedNode *pred = C.getPredecessor();
|
|
for (Stmt::const_child_iterator it = Ex->child_begin(), et = Ex->child_end() ;
|
|
it != et ; ++it) {
|
|
const Stmt *child = *it;
|
|
SVal V = state->getSVal(child, pred->getLocationContext());
|
|
if (SymbolRef sym = V.getAsSymbol())
|
|
if (const RefVal* T = getRefBinding(state, sym)) {
|
|
RefVal::Kind hasErr = (RefVal::Kind) 0;
|
|
state = updateSymbol(state, sym, *T, MayEscape, hasErr, C);
|
|
if (hasErr) {
|
|
processNonLeakError(state, child->getSourceRange(), hasErr, sym, C);
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Return the object as autoreleased.
|
|
// RetEffect RE = RetEffect::MakeNotOwned(RetEffect::ObjC);
|
|
if (SymbolRef sym =
|
|
state->getSVal(Ex, pred->getLocationContext()).getAsSymbol()) {
|
|
QualType ResultTy = Ex->getType();
|
|
state = setRefBinding(state, sym,
|
|
RefVal::makeNotOwned(RetEffect::ObjC, ResultTy));
|
|
}
|
|
|
|
C.addTransition(state);
|
|
}
|
|
|
|
void RetainCountChecker::checkPostStmt(const ObjCArrayLiteral *AL,
|
|
CheckerContext &C) const {
|
|
// Apply the 'MayEscape' to all values.
|
|
processObjCLiterals(C, AL);
|
|
}
|
|
|
|
void RetainCountChecker::checkPostStmt(const ObjCDictionaryLiteral *DL,
|
|
CheckerContext &C) const {
|
|
// Apply the 'MayEscape' to all keys and values.
|
|
processObjCLiterals(C, DL);
|
|
}
|
|
|
|
void RetainCountChecker::checkPostStmt(const ObjCBoxedExpr *Ex,
|
|
CheckerContext &C) const {
|
|
const ExplodedNode *Pred = C.getPredecessor();
|
|
const LocationContext *LCtx = Pred->getLocationContext();
|
|
ProgramStateRef State = Pred->getState();
|
|
|
|
if (SymbolRef Sym = State->getSVal(Ex, LCtx).getAsSymbol()) {
|
|
QualType ResultTy = Ex->getType();
|
|
State = setRefBinding(State, Sym,
|
|
RefVal::makeNotOwned(RetEffect::ObjC, ResultTy));
|
|
}
|
|
|
|
C.addTransition(State);
|
|
}
|
|
|
|
void RetainCountChecker::checkPostStmt(const ObjCIvarRefExpr *IRE,
|
|
CheckerContext &C) const {
|
|
ProgramStateRef State = C.getState();
|
|
// If an instance variable was previously accessed through a property,
|
|
// it may have a synthesized refcount of +0. Override right now that we're
|
|
// doing direct access.
|
|
if (Optional<Loc> IVarLoc = C.getSVal(IRE).getAs<Loc>())
|
|
if (SymbolRef Sym = State->getSVal(*IVarLoc).getAsSymbol())
|
|
if (const RefVal *RV = getRefBinding(State, Sym))
|
|
if (RV->isOverridable())
|
|
State = removeRefBinding(State, Sym);
|
|
C.addTransition(State);
|
|
}
|
|
|
|
void RetainCountChecker::checkPostCall(const CallEvent &Call,
|
|
CheckerContext &C) const {
|
|
RetainSummaryManager &Summaries = getSummaryManager(C);
|
|
const RetainSummary *Summ = Summaries.getSummary(Call, C.getState());
|
|
|
|
if (C.wasInlined) {
|
|
processSummaryOfInlined(*Summ, Call, C);
|
|
return;
|
|
}
|
|
checkSummary(*Summ, Call, C);
|
|
}
|
|
|
|
/// GetReturnType - Used to get the return type of a message expression or
|
|
/// function call with the intention of affixing that type to a tracked symbol.
|
|
/// While the return type can be queried directly from RetEx, when
|
|
/// invoking class methods we augment to the return type to be that of
|
|
/// a pointer to the class (as opposed it just being id).
|
|
// FIXME: We may be able to do this with related result types instead.
|
|
// This function is probably overestimating.
|
|
static QualType GetReturnType(const Expr *RetE, ASTContext &Ctx) {
|
|
QualType RetTy = RetE->getType();
|
|
// If RetE is not a message expression just return its type.
|
|
// If RetE is a message expression, return its types if it is something
|
|
/// more specific than id.
|
|
if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(RetE))
|
|
if (const ObjCObjectPointerType *PT = RetTy->getAs<ObjCObjectPointerType>())
|
|
if (PT->isObjCQualifiedIdType() || PT->isObjCIdType() ||
|
|
PT->isObjCClassType()) {
|
|
// At this point we know the return type of the message expression is
|
|
// id, id<...>, or Class. If we have an ObjCInterfaceDecl, we know this
|
|
// is a call to a class method whose type we can resolve. In such
|
|
// cases, promote the return type to XXX* (where XXX is the class).
|
|
const ObjCInterfaceDecl *D = ME->getReceiverInterface();
|
|
return !D ? RetTy :
|
|
Ctx.getObjCObjectPointerType(Ctx.getObjCInterfaceType(D));
|
|
}
|
|
|
|
return RetTy;
|
|
}
|
|
|
|
static bool wasSynthesizedProperty(const ObjCMethodCall *Call,
|
|
ExplodedNode *N) {
|
|
if (!Call || !Call->getDecl()->isPropertyAccessor())
|
|
return false;
|
|
|
|
CallExitEnd PP = N->getLocation().castAs<CallExitEnd>();
|
|
const StackFrameContext *Frame = PP.getCalleeContext();
|
|
return Frame->getAnalysisDeclContext()->isBodyAutosynthesized();
|
|
}
|
|
|
|
// We don't always get the exact modeling of the function with regards to the
|
|
// retain count checker even when the function is inlined. For example, we need
|
|
// to stop tracking the symbols which were marked with StopTrackingHard.
|
|
void RetainCountChecker::processSummaryOfInlined(const RetainSummary &Summ,
|
|
const CallEvent &CallOrMsg,
|
|
CheckerContext &C) const {
|
|
ProgramStateRef state = C.getState();
|
|
|
|
// Evaluate the effect of the arguments.
|
|
for (unsigned idx = 0, e = CallOrMsg.getNumArgs(); idx != e; ++idx) {
|
|
if (Summ.getArg(idx) == StopTrackingHard) {
|
|
SVal V = CallOrMsg.getArgSVal(idx);
|
|
if (SymbolRef Sym = V.getAsLocSymbol()) {
|
|
state = removeRefBinding(state, Sym);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Evaluate the effect on the message receiver.
|
|
const ObjCMethodCall *MsgInvocation = dyn_cast<ObjCMethodCall>(&CallOrMsg);
|
|
if (MsgInvocation) {
|
|
if (SymbolRef Sym = MsgInvocation->getReceiverSVal().getAsLocSymbol()) {
|
|
if (Summ.getReceiverEffect() == StopTrackingHard) {
|
|
state = removeRefBinding(state, Sym);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Consult the summary for the return value.
|
|
RetEffect RE = Summ.getRetEffect();
|
|
if (RE.getKind() == RetEffect::NoRetHard) {
|
|
SymbolRef Sym = CallOrMsg.getReturnValue().getAsSymbol();
|
|
if (Sym)
|
|
state = removeRefBinding(state, Sym);
|
|
} else if (RE.getKind() == RetEffect::NotOwnedSymbol) {
|
|
if (wasSynthesizedProperty(MsgInvocation, C.getPredecessor())) {
|
|
// Believe the summary if we synthesized the body of a property getter
|
|
// and the return value is currently untracked. If the corresponding
|
|
// instance variable is later accessed directly, however, we're going to
|
|
// want to override this state, so that the owning object can perform
|
|
// reference counting operations on its own ivars.
|
|
SymbolRef Sym = CallOrMsg.getReturnValue().getAsSymbol();
|
|
if (Sym && !getRefBinding(state, Sym))
|
|
state = setRefBinding(state, Sym,
|
|
RefVal::makeOverridableNotOwned(RE.getObjKind(),
|
|
Sym->getType()));
|
|
}
|
|
}
|
|
|
|
C.addTransition(state);
|
|
}
|
|
|
|
void RetainCountChecker::checkSummary(const RetainSummary &Summ,
|
|
const CallEvent &CallOrMsg,
|
|
CheckerContext &C) const {
|
|
ProgramStateRef state = C.getState();
|
|
|
|
// Evaluate the effect of the arguments.
|
|
RefVal::Kind hasErr = (RefVal::Kind) 0;
|
|
SourceRange ErrorRange;
|
|
SymbolRef ErrorSym = 0;
|
|
|
|
for (unsigned idx = 0, e = CallOrMsg.getNumArgs(); idx != e; ++idx) {
|
|
SVal V = CallOrMsg.getArgSVal(idx);
|
|
|
|
if (SymbolRef Sym = V.getAsLocSymbol()) {
|
|
if (const RefVal *T = getRefBinding(state, Sym)) {
|
|
state = updateSymbol(state, Sym, *T, Summ.getArg(idx), hasErr, C);
|
|
if (hasErr) {
|
|
ErrorRange = CallOrMsg.getArgSourceRange(idx);
|
|
ErrorSym = Sym;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Evaluate the effect on the message receiver.
|
|
bool ReceiverIsTracked = false;
|
|
if (!hasErr) {
|
|
const ObjCMethodCall *MsgInvocation = dyn_cast<ObjCMethodCall>(&CallOrMsg);
|
|
if (MsgInvocation) {
|
|
if (SymbolRef Sym = MsgInvocation->getReceiverSVal().getAsLocSymbol()) {
|
|
if (const RefVal *T = getRefBinding(state, Sym)) {
|
|
ReceiverIsTracked = true;
|
|
state = updateSymbol(state, Sym, *T, Summ.getReceiverEffect(),
|
|
hasErr, C);
|
|
if (hasErr) {
|
|
ErrorRange = MsgInvocation->getOriginExpr()->getReceiverRange();
|
|
ErrorSym = Sym;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Process any errors.
|
|
if (hasErr) {
|
|
processNonLeakError(state, ErrorRange, hasErr, ErrorSym, C);
|
|
return;
|
|
}
|
|
|
|
// Consult the summary for the return value.
|
|
RetEffect RE = Summ.getRetEffect();
|
|
|
|
if (RE.getKind() == RetEffect::OwnedWhenTrackedReceiver) {
|
|
if (ReceiverIsTracked)
|
|
RE = getSummaryManager(C).getObjAllocRetEffect();
|
|
else
|
|
RE = RetEffect::MakeNoRet();
|
|
}
|
|
|
|
switch (RE.getKind()) {
|
|
default:
|
|
llvm_unreachable("Unhandled RetEffect.");
|
|
|
|
case RetEffect::NoRet:
|
|
case RetEffect::NoRetHard:
|
|
// No work necessary.
|
|
break;
|
|
|
|
case RetEffect::OwnedAllocatedSymbol:
|
|
case RetEffect::OwnedSymbol: {
|
|
SymbolRef Sym = CallOrMsg.getReturnValue().getAsSymbol();
|
|
if (!Sym)
|
|
break;
|
|
|
|
// Use the result type from the CallEvent as it automatically adjusts
|
|
// for methods/functions that return references.
|
|
QualType ResultTy = CallOrMsg.getResultType();
|
|
state = setRefBinding(state, Sym, RefVal::makeOwned(RE.getObjKind(),
|
|
ResultTy));
|
|
|
|
// FIXME: Add a flag to the checker where allocations are assumed to
|
|
// *not* fail.
|
|
break;
|
|
}
|
|
|
|
case RetEffect::GCNotOwnedSymbol:
|
|
case RetEffect::NotOwnedSymbol: {
|
|
const Expr *Ex = CallOrMsg.getOriginExpr();
|
|
SymbolRef Sym = CallOrMsg.getReturnValue().getAsSymbol();
|
|
if (!Sym)
|
|
break;
|
|
assert(Ex);
|
|
// Use GetReturnType in order to give [NSFoo alloc] the type NSFoo *.
|
|
QualType ResultTy = GetReturnType(Ex, C.getASTContext());
|
|
state = setRefBinding(state, Sym, RefVal::makeNotOwned(RE.getObjKind(),
|
|
ResultTy));
|
|
break;
|
|
}
|
|
}
|
|
|
|
// This check is actually necessary; otherwise the statement builder thinks
|
|
// we've hit a previously-found path.
|
|
// Normally addTransition takes care of this, but we want the node pointer.
|
|
ExplodedNode *NewNode;
|
|
if (state == C.getState()) {
|
|
NewNode = C.getPredecessor();
|
|
} else {
|
|
NewNode = C.addTransition(state);
|
|
}
|
|
|
|
// Annotate the node with summary we used.
|
|
if (NewNode) {
|
|
// FIXME: This is ugly. See checkEndAnalysis for why it's necessary.
|
|
if (ShouldResetSummaryLog) {
|
|
SummaryLog.clear();
|
|
ShouldResetSummaryLog = false;
|
|
}
|
|
SummaryLog[NewNode] = &Summ;
|
|
}
|
|
}
|
|
|
|
|
|
ProgramStateRef
|
|
RetainCountChecker::updateSymbol(ProgramStateRef state, SymbolRef sym,
|
|
RefVal V, ArgEffect E, RefVal::Kind &hasErr,
|
|
CheckerContext &C) const {
|
|
// In GC mode [... release] and [... retain] do nothing.
|
|
// In ARC mode they shouldn't exist at all, but we just ignore them.
|
|
bool IgnoreRetainMsg = C.isObjCGCEnabled();
|
|
if (!IgnoreRetainMsg)
|
|
IgnoreRetainMsg = (bool)C.getASTContext().getLangOpts().ObjCAutoRefCount;
|
|
|
|
switch (E) {
|
|
default:
|
|
break;
|
|
case IncRefMsg:
|
|
E = IgnoreRetainMsg ? DoNothing : IncRef;
|
|
break;
|
|
case DecRefMsg:
|
|
E = IgnoreRetainMsg ? DoNothing : DecRef;
|
|
break;
|
|
case DecRefMsgAndStopTrackingHard:
|
|
E = IgnoreRetainMsg ? StopTracking : DecRefAndStopTrackingHard;
|
|
break;
|
|
case MakeCollectable:
|
|
E = C.isObjCGCEnabled() ? DecRef : DoNothing;
|
|
break;
|
|
}
|
|
|
|
// Handle all use-after-releases.
|
|
if (!C.isObjCGCEnabled() && V.getKind() == RefVal::Released) {
|
|
V = V ^ RefVal::ErrorUseAfterRelease;
|
|
hasErr = V.getKind();
|
|
return setRefBinding(state, sym, V);
|
|
}
|
|
|
|
switch (E) {
|
|
case DecRefMsg:
|
|
case IncRefMsg:
|
|
case MakeCollectable:
|
|
case DecRefMsgAndStopTrackingHard:
|
|
llvm_unreachable("DecRefMsg/IncRefMsg/MakeCollectable already converted");
|
|
|
|
case Dealloc:
|
|
// Any use of -dealloc in GC is *bad*.
|
|
if (C.isObjCGCEnabled()) {
|
|
V = V ^ RefVal::ErrorDeallocGC;
|
|
hasErr = V.getKind();
|
|
break;
|
|
}
|
|
|
|
switch (V.getKind()) {
|
|
default:
|
|
llvm_unreachable("Invalid RefVal state for an explicit dealloc.");
|
|
case RefVal::Owned:
|
|
// The object immediately transitions to the released state.
|
|
V = V ^ RefVal::Released;
|
|
V.clearCounts();
|
|
return setRefBinding(state, sym, V);
|
|
case RefVal::NotOwned:
|
|
V = V ^ RefVal::ErrorDeallocNotOwned;
|
|
hasErr = V.getKind();
|
|
break;
|
|
}
|
|
break;
|
|
|
|
case MayEscape:
|
|
if (V.getKind() == RefVal::Owned) {
|
|
V = V ^ RefVal::NotOwned;
|
|
break;
|
|
}
|
|
|
|
// Fall-through.
|
|
|
|
case DoNothing:
|
|
return state;
|
|
|
|
case Autorelease:
|
|
if (C.isObjCGCEnabled())
|
|
return state;
|
|
// Update the autorelease counts.
|
|
V = V.autorelease();
|
|
break;
|
|
|
|
case StopTracking:
|
|
case StopTrackingHard:
|
|
return removeRefBinding(state, sym);
|
|
|
|
case IncRef:
|
|
switch (V.getKind()) {
|
|
default:
|
|
llvm_unreachable("Invalid RefVal state for a retain.");
|
|
case RefVal::Owned:
|
|
case RefVal::NotOwned:
|
|
V = V + 1;
|
|
break;
|
|
case RefVal::Released:
|
|
// Non-GC cases are handled above.
|
|
assert(C.isObjCGCEnabled());
|
|
V = (V ^ RefVal::Owned) + 1;
|
|
break;
|
|
}
|
|
break;
|
|
|
|
case DecRef:
|
|
case DecRefBridgedTransferred:
|
|
case DecRefAndStopTrackingHard:
|
|
switch (V.getKind()) {
|
|
default:
|
|
// case 'RefVal::Released' handled above.
|
|
llvm_unreachable("Invalid RefVal state for a release.");
|
|
|
|
case RefVal::Owned:
|
|
assert(V.getCount() > 0);
|
|
if (V.getCount() == 1)
|
|
V = V ^ (E == DecRefBridgedTransferred ? RefVal::NotOwned
|
|
: RefVal::Released);
|
|
else if (E == DecRefAndStopTrackingHard)
|
|
return removeRefBinding(state, sym);
|
|
|
|
V = V - 1;
|
|
break;
|
|
|
|
case RefVal::NotOwned:
|
|
if (V.getCount() > 0) {
|
|
if (E == DecRefAndStopTrackingHard)
|
|
return removeRefBinding(state, sym);
|
|
V = V - 1;
|
|
} else {
|
|
V = V ^ RefVal::ErrorReleaseNotOwned;
|
|
hasErr = V.getKind();
|
|
}
|
|
break;
|
|
|
|
case RefVal::Released:
|
|
// Non-GC cases are handled above.
|
|
assert(C.isObjCGCEnabled());
|
|
V = V ^ RefVal::ErrorUseAfterRelease;
|
|
hasErr = V.getKind();
|
|
break;
|
|
}
|
|
break;
|
|
}
|
|
return setRefBinding(state, sym, V);
|
|
}
|
|
|
|
void RetainCountChecker::processNonLeakError(ProgramStateRef St,
|
|
SourceRange ErrorRange,
|
|
RefVal::Kind ErrorKind,
|
|
SymbolRef Sym,
|
|
CheckerContext &C) const {
|
|
ExplodedNode *N = C.generateSink(St);
|
|
if (!N)
|
|
return;
|
|
|
|
CFRefBug *BT;
|
|
switch (ErrorKind) {
|
|
default:
|
|
llvm_unreachable("Unhandled error.");
|
|
case RefVal::ErrorUseAfterRelease:
|
|
if (!useAfterRelease)
|
|
useAfterRelease.reset(new UseAfterRelease(this));
|
|
BT = &*useAfterRelease;
|
|
break;
|
|
case RefVal::ErrorReleaseNotOwned:
|
|
if (!releaseNotOwned)
|
|
releaseNotOwned.reset(new BadRelease(this));
|
|
BT = &*releaseNotOwned;
|
|
break;
|
|
case RefVal::ErrorDeallocGC:
|
|
if (!deallocGC)
|
|
deallocGC.reset(new DeallocGC(this));
|
|
BT = &*deallocGC;
|
|
break;
|
|
case RefVal::ErrorDeallocNotOwned:
|
|
if (!deallocNotOwned)
|
|
deallocNotOwned.reset(new DeallocNotOwned(this));
|
|
BT = &*deallocNotOwned;
|
|
break;
|
|
}
|
|
|
|
assert(BT);
|
|
CFRefReport *report = new CFRefReport(*BT, C.getASTContext().getLangOpts(),
|
|
C.isObjCGCEnabled(), SummaryLog,
|
|
N, Sym);
|
|
report->addRange(ErrorRange);
|
|
C.emitReport(report);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Handle the return values of retain-count-related functions.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
bool RetainCountChecker::evalCall(const CallExpr *CE, CheckerContext &C) const {
|
|
// Get the callee. We're only interested in simple C functions.
|
|
ProgramStateRef state = C.getState();
|
|
const FunctionDecl *FD = C.getCalleeDecl(CE);
|
|
if (!FD)
|
|
return false;
|
|
|
|
IdentifierInfo *II = FD->getIdentifier();
|
|
if (!II)
|
|
return false;
|
|
|
|
// For now, we're only handling the functions that return aliases of their
|
|
// arguments: CFRetain and CFMakeCollectable (and their families).
|
|
// Eventually we should add other functions we can model entirely,
|
|
// such as CFRelease, which don't invalidate their arguments or globals.
|
|
if (CE->getNumArgs() != 1)
|
|
return false;
|
|
|
|
// Get the name of the function.
|
|
StringRef FName = II->getName();
|
|
FName = FName.substr(FName.find_first_not_of('_'));
|
|
|
|
// See if it's one of the specific functions we know how to eval.
|
|
bool canEval = false;
|
|
|
|
QualType ResultTy = CE->getCallReturnType();
|
|
if (ResultTy->isObjCIdType()) {
|
|
// Handle: id NSMakeCollectable(CFTypeRef)
|
|
canEval = II->isStr("NSMakeCollectable");
|
|
} else if (ResultTy->isPointerType()) {
|
|
// Handle: (CF|CG)Retain
|
|
// CFAutorelease
|
|
// CFMakeCollectable
|
|
// It's okay to be a little sloppy here (CGMakeCollectable doesn't exist).
|
|
if (cocoa::isRefType(ResultTy, "CF", FName) ||
|
|
cocoa::isRefType(ResultTy, "CG", FName)) {
|
|
canEval = isRetain(FD, FName) || isAutorelease(FD, FName) ||
|
|
isMakeCollectable(FD, FName);
|
|
}
|
|
}
|
|
|
|
if (!canEval)
|
|
return false;
|
|
|
|
// Bind the return value.
|
|
const LocationContext *LCtx = C.getLocationContext();
|
|
SVal RetVal = state->getSVal(CE->getArg(0), LCtx);
|
|
if (RetVal.isUnknown()) {
|
|
// If the receiver is unknown, conjure a return value.
|
|
SValBuilder &SVB = C.getSValBuilder();
|
|
RetVal = SVB.conjureSymbolVal(0, CE, LCtx, ResultTy, C.blockCount());
|
|
}
|
|
state = state->BindExpr(CE, LCtx, RetVal, false);
|
|
|
|
// FIXME: This should not be necessary, but otherwise the argument seems to be
|
|
// considered alive during the next statement.
|
|
if (const MemRegion *ArgRegion = RetVal.getAsRegion()) {
|
|
// Save the refcount status of the argument.
|
|
SymbolRef Sym = RetVal.getAsLocSymbol();
|
|
const RefVal *Binding = 0;
|
|
if (Sym)
|
|
Binding = getRefBinding(state, Sym);
|
|
|
|
// Invalidate the argument region.
|
|
state = state->invalidateRegions(ArgRegion, CE, C.blockCount(), LCtx,
|
|
/*CausesPointerEscape*/ false);
|
|
|
|
// Restore the refcount status of the argument.
|
|
if (Binding)
|
|
state = setRefBinding(state, Sym, *Binding);
|
|
}
|
|
|
|
C.addTransition(state);
|
|
return true;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Handle return statements.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void RetainCountChecker::checkPreStmt(const ReturnStmt *S,
|
|
CheckerContext &C) const {
|
|
|
|
// Only adjust the reference count if this is the top-level call frame,
|
|
// and not the result of inlining. In the future, we should do
|
|
// better checking even for inlined calls, and see if they match
|
|
// with their expected semantics (e.g., the method should return a retained
|
|
// object, etc.).
|
|
if (!C.inTopFrame())
|
|
return;
|
|
|
|
const Expr *RetE = S->getRetValue();
|
|
if (!RetE)
|
|
return;
|
|
|
|
ProgramStateRef state = C.getState();
|
|
SymbolRef Sym =
|
|
state->getSValAsScalarOrLoc(RetE, C.getLocationContext()).getAsLocSymbol();
|
|
if (!Sym)
|
|
return;
|
|
|
|
// Get the reference count binding (if any).
|
|
const RefVal *T = getRefBinding(state, Sym);
|
|
if (!T)
|
|
return;
|
|
|
|
// Change the reference count.
|
|
RefVal X = *T;
|
|
|
|
switch (X.getKind()) {
|
|
case RefVal::Owned: {
|
|
unsigned cnt = X.getCount();
|
|
assert(cnt > 0);
|
|
X.setCount(cnt - 1);
|
|
X = X ^ RefVal::ReturnedOwned;
|
|
break;
|
|
}
|
|
|
|
case RefVal::NotOwned: {
|
|
unsigned cnt = X.getCount();
|
|
if (cnt) {
|
|
X.setCount(cnt - 1);
|
|
X = X ^ RefVal::ReturnedOwned;
|
|
}
|
|
else {
|
|
X = X ^ RefVal::ReturnedNotOwned;
|
|
}
|
|
break;
|
|
}
|
|
|
|
default:
|
|
return;
|
|
}
|
|
|
|
// Update the binding.
|
|
state = setRefBinding(state, Sym, X);
|
|
ExplodedNode *Pred = C.addTransition(state);
|
|
|
|
// At this point we have updated the state properly.
|
|
// Everything after this is merely checking to see if the return value has
|
|
// been over- or under-retained.
|
|
|
|
// Did we cache out?
|
|
if (!Pred)
|
|
return;
|
|
|
|
// Update the autorelease counts.
|
|
static CheckerProgramPointTag AutoreleaseTag(this, "Autorelease");
|
|
state = handleAutoreleaseCounts(state, Pred, &AutoreleaseTag, C, Sym, X);
|
|
|
|
// Did we cache out?
|
|
if (!state)
|
|
return;
|
|
|
|
// Get the updated binding.
|
|
T = getRefBinding(state, Sym);
|
|
assert(T);
|
|
X = *T;
|
|
|
|
// Consult the summary of the enclosing method.
|
|
RetainSummaryManager &Summaries = getSummaryManager(C);
|
|
const Decl *CD = &Pred->getCodeDecl();
|
|
RetEffect RE = RetEffect::MakeNoRet();
|
|
|
|
// FIXME: What is the convention for blocks? Is there one?
|
|
if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(CD)) {
|
|
const RetainSummary *Summ = Summaries.getMethodSummary(MD);
|
|
RE = Summ->getRetEffect();
|
|
} else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(CD)) {
|
|
if (!isa<CXXMethodDecl>(FD)) {
|
|
const RetainSummary *Summ = Summaries.getFunctionSummary(FD);
|
|
RE = Summ->getRetEffect();
|
|
}
|
|
}
|
|
|
|
checkReturnWithRetEffect(S, C, Pred, RE, X, Sym, state);
|
|
}
|
|
|
|
void RetainCountChecker::checkReturnWithRetEffect(const ReturnStmt *S,
|
|
CheckerContext &C,
|
|
ExplodedNode *Pred,
|
|
RetEffect RE, RefVal X,
|
|
SymbolRef Sym,
|
|
ProgramStateRef state) const {
|
|
// Any leaks or other errors?
|
|
if (X.isReturnedOwned() && X.getCount() == 0) {
|
|
if (RE.getKind() != RetEffect::NoRet) {
|
|
bool hasError = false;
|
|
if (C.isObjCGCEnabled() && RE.getObjKind() == RetEffect::ObjC) {
|
|
// Things are more complicated with garbage collection. If the
|
|
// returned object is suppose to be an Objective-C object, we have
|
|
// a leak (as the caller expects a GC'ed object) because no
|
|
// method should return ownership unless it returns a CF object.
|
|
hasError = true;
|
|
X = X ^ RefVal::ErrorGCLeakReturned;
|
|
}
|
|
else if (!RE.isOwned()) {
|
|
// Either we are using GC and the returned object is a CF type
|
|
// or we aren't using GC. In either case, we expect that the
|
|
// enclosing method is expected to return ownership.
|
|
hasError = true;
|
|
X = X ^ RefVal::ErrorLeakReturned;
|
|
}
|
|
|
|
if (hasError) {
|
|
// Generate an error node.
|
|
state = setRefBinding(state, Sym, X);
|
|
|
|
static CheckerProgramPointTag ReturnOwnLeakTag(this, "ReturnsOwnLeak");
|
|
ExplodedNode *N = C.addTransition(state, Pred, &ReturnOwnLeakTag);
|
|
if (N) {
|
|
const LangOptions &LOpts = C.getASTContext().getLangOpts();
|
|
bool GCEnabled = C.isObjCGCEnabled();
|
|
CFRefReport *report =
|
|
new CFRefLeakReport(*getLeakAtReturnBug(LOpts, GCEnabled),
|
|
LOpts, GCEnabled, SummaryLog,
|
|
N, Sym, C, IncludeAllocationLine);
|
|
|
|
C.emitReport(report);
|
|
}
|
|
}
|
|
}
|
|
} else if (X.isReturnedNotOwned()) {
|
|
if (RE.isOwned()) {
|
|
// Trying to return a not owned object to a caller expecting an
|
|
// owned object.
|
|
state = setRefBinding(state, Sym, X ^ RefVal::ErrorReturnedNotOwned);
|
|
|
|
static CheckerProgramPointTag ReturnNotOwnedTag(this,
|
|
"ReturnNotOwnedForOwned");
|
|
ExplodedNode *N = C.addTransition(state, Pred, &ReturnNotOwnedTag);
|
|
if (N) {
|
|
if (!returnNotOwnedForOwned)
|
|
returnNotOwnedForOwned.reset(new ReturnedNotOwnedForOwned(this));
|
|
|
|
CFRefReport *report =
|
|
new CFRefReport(*returnNotOwnedForOwned,
|
|
C.getASTContext().getLangOpts(),
|
|
C.isObjCGCEnabled(), SummaryLog, N, Sym);
|
|
C.emitReport(report);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Check various ways a symbol can be invalidated.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void RetainCountChecker::checkBind(SVal loc, SVal val, const Stmt *S,
|
|
CheckerContext &C) const {
|
|
// Are we storing to something that causes the value to "escape"?
|
|
bool escapes = true;
|
|
|
|
// A value escapes in three possible cases (this may change):
|
|
//
|
|
// (1) we are binding to something that is not a memory region.
|
|
// (2) we are binding to a memregion that does not have stack storage
|
|
// (3) we are binding to a memregion with stack storage that the store
|
|
// does not understand.
|
|
ProgramStateRef state = C.getState();
|
|
|
|
if (Optional<loc::MemRegionVal> regionLoc = loc.getAs<loc::MemRegionVal>()) {
|
|
escapes = !regionLoc->getRegion()->hasStackStorage();
|
|
|
|
if (!escapes) {
|
|
// To test (3), generate a new state with the binding added. If it is
|
|
// the same state, then it escapes (since the store cannot represent
|
|
// the binding).
|
|
// Do this only if we know that the store is not supposed to generate the
|
|
// same state.
|
|
SVal StoredVal = state->getSVal(regionLoc->getRegion());
|
|
if (StoredVal != val)
|
|
escapes = (state == (state->bindLoc(*regionLoc, val)));
|
|
}
|
|
if (!escapes) {
|
|
// Case 4: We do not currently model what happens when a symbol is
|
|
// assigned to a struct field, so be conservative here and let the symbol
|
|
// go. TODO: This could definitely be improved upon.
|
|
escapes = !isa<VarRegion>(regionLoc->getRegion());
|
|
}
|
|
}
|
|
|
|
// If we are storing the value into an auto function scope variable annotated
|
|
// with (__attribute__((cleanup))), stop tracking the value to avoid leak
|
|
// false positives.
|
|
if (const VarRegion *LVR = dyn_cast_or_null<VarRegion>(loc.getAsRegion())) {
|
|
const VarDecl *VD = LVR->getDecl();
|
|
if (VD->hasAttr<CleanupAttr>()) {
|
|
escapes = true;
|
|
}
|
|
}
|
|
|
|
// If our store can represent the binding and we aren't storing to something
|
|
// that doesn't have local storage then just return and have the simulation
|
|
// state continue as is.
|
|
if (!escapes)
|
|
return;
|
|
|
|
// Otherwise, find all symbols referenced by 'val' that we are tracking
|
|
// and stop tracking them.
|
|
state = state->scanReachableSymbols<StopTrackingCallback>(val).getState();
|
|
C.addTransition(state);
|
|
}
|
|
|
|
ProgramStateRef RetainCountChecker::evalAssume(ProgramStateRef state,
|
|
SVal Cond,
|
|
bool Assumption) const {
|
|
|
|
// FIXME: We may add to the interface of evalAssume the list of symbols
|
|
// whose assumptions have changed. For now we just iterate through the
|
|
// bindings and check if any of the tracked symbols are NULL. This isn't
|
|
// too bad since the number of symbols we will track in practice are
|
|
// probably small and evalAssume is only called at branches and a few
|
|
// other places.
|
|
RefBindingsTy B = state->get<RefBindings>();
|
|
|
|
if (B.isEmpty())
|
|
return state;
|
|
|
|
bool changed = false;
|
|
RefBindingsTy::Factory &RefBFactory = state->get_context<RefBindings>();
|
|
|
|
for (RefBindingsTy::iterator I = B.begin(), E = B.end(); I != E; ++I) {
|
|
// Check if the symbol is null stop tracking the symbol.
|
|
ConstraintManager &CMgr = state->getConstraintManager();
|
|
ConditionTruthVal AllocFailed = CMgr.isNull(state, I.getKey());
|
|
if (AllocFailed.isConstrainedTrue()) {
|
|
changed = true;
|
|
B = RefBFactory.remove(B, I.getKey());
|
|
}
|
|
}
|
|
|
|
if (changed)
|
|
state = state->set<RefBindings>(B);
|
|
|
|
return state;
|
|
}
|
|
|
|
ProgramStateRef
|
|
RetainCountChecker::checkRegionChanges(ProgramStateRef state,
|
|
const InvalidatedSymbols *invalidated,
|
|
ArrayRef<const MemRegion *> ExplicitRegions,
|
|
ArrayRef<const MemRegion *> Regions,
|
|
const CallEvent *Call) const {
|
|
if (!invalidated)
|
|
return state;
|
|
|
|
llvm::SmallPtrSet<SymbolRef, 8> WhitelistedSymbols;
|
|
for (ArrayRef<const MemRegion *>::iterator I = ExplicitRegions.begin(),
|
|
E = ExplicitRegions.end(); I != E; ++I) {
|
|
if (const SymbolicRegion *SR = (*I)->StripCasts()->getAs<SymbolicRegion>())
|
|
WhitelistedSymbols.insert(SR->getSymbol());
|
|
}
|
|
|
|
for (InvalidatedSymbols::const_iterator I=invalidated->begin(),
|
|
E = invalidated->end(); I!=E; ++I) {
|
|
SymbolRef sym = *I;
|
|
if (WhitelistedSymbols.count(sym))
|
|
continue;
|
|
// Remove any existing reference-count binding.
|
|
state = removeRefBinding(state, sym);
|
|
}
|
|
return state;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Handle dead symbols and end-of-path.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
ProgramStateRef
|
|
RetainCountChecker::handleAutoreleaseCounts(ProgramStateRef state,
|
|
ExplodedNode *Pred,
|
|
const ProgramPointTag *Tag,
|
|
CheckerContext &Ctx,
|
|
SymbolRef Sym, RefVal V) const {
|
|
unsigned ACnt = V.getAutoreleaseCount();
|
|
|
|
// No autorelease counts? Nothing to be done.
|
|
if (!ACnt)
|
|
return state;
|
|
|
|
assert(!Ctx.isObjCGCEnabled() && "Autorelease counts in GC mode?");
|
|
unsigned Cnt = V.getCount();
|
|
|
|
// FIXME: Handle sending 'autorelease' to already released object.
|
|
|
|
if (V.getKind() == RefVal::ReturnedOwned)
|
|
++Cnt;
|
|
|
|
if (ACnt <= Cnt) {
|
|
if (ACnt == Cnt) {
|
|
V.clearCounts();
|
|
if (V.getKind() == RefVal::ReturnedOwned)
|
|
V = V ^ RefVal::ReturnedNotOwned;
|
|
else
|
|
V = V ^ RefVal::NotOwned;
|
|
} else {
|
|
V.setCount(V.getCount() - ACnt);
|
|
V.setAutoreleaseCount(0);
|
|
}
|
|
return setRefBinding(state, Sym, V);
|
|
}
|
|
|
|
// Woah! More autorelease counts then retain counts left.
|
|
// Emit hard error.
|
|
V = V ^ RefVal::ErrorOverAutorelease;
|
|
state = setRefBinding(state, Sym, V);
|
|
|
|
ExplodedNode *N = Ctx.generateSink(state, Pred, Tag);
|
|
if (N) {
|
|
SmallString<128> sbuf;
|
|
llvm::raw_svector_ostream os(sbuf);
|
|
os << "Object was autoreleased ";
|
|
if (V.getAutoreleaseCount() > 1)
|
|
os << V.getAutoreleaseCount() << " times but the object ";
|
|
else
|
|
os << "but ";
|
|
os << "has a +" << V.getCount() << " retain count";
|
|
|
|
if (!overAutorelease)
|
|
overAutorelease.reset(new OverAutorelease(this));
|
|
|
|
const LangOptions &LOpts = Ctx.getASTContext().getLangOpts();
|
|
CFRefReport *report =
|
|
new CFRefReport(*overAutorelease, LOpts, /* GCEnabled = */ false,
|
|
SummaryLog, N, Sym, os.str());
|
|
Ctx.emitReport(report);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
ProgramStateRef
|
|
RetainCountChecker::handleSymbolDeath(ProgramStateRef state,
|
|
SymbolRef sid, RefVal V,
|
|
SmallVectorImpl<SymbolRef> &Leaked) const {
|
|
bool hasLeak = false;
|
|
if (V.isOwned())
|
|
hasLeak = true;
|
|
else if (V.isNotOwned() || V.isReturnedOwned())
|
|
hasLeak = (V.getCount() > 0);
|
|
|
|
if (!hasLeak)
|
|
return removeRefBinding(state, sid);
|
|
|
|
Leaked.push_back(sid);
|
|
return setRefBinding(state, sid, V ^ RefVal::ErrorLeak);
|
|
}
|
|
|
|
ExplodedNode *
|
|
RetainCountChecker::processLeaks(ProgramStateRef state,
|
|
SmallVectorImpl<SymbolRef> &Leaked,
|
|
CheckerContext &Ctx,
|
|
ExplodedNode *Pred) const {
|
|
// Generate an intermediate node representing the leak point.
|
|
ExplodedNode *N = Ctx.addTransition(state, Pred);
|
|
|
|
if (N) {
|
|
for (SmallVectorImpl<SymbolRef>::iterator
|
|
I = Leaked.begin(), E = Leaked.end(); I != E; ++I) {
|
|
|
|
const LangOptions &LOpts = Ctx.getASTContext().getLangOpts();
|
|
bool GCEnabled = Ctx.isObjCGCEnabled();
|
|
CFRefBug *BT = Pred ? getLeakWithinFunctionBug(LOpts, GCEnabled)
|
|
: getLeakAtReturnBug(LOpts, GCEnabled);
|
|
assert(BT && "BugType not initialized.");
|
|
|
|
CFRefLeakReport *report = new CFRefLeakReport(*BT, LOpts, GCEnabled,
|
|
SummaryLog, N, *I, Ctx,
|
|
IncludeAllocationLine);
|
|
Ctx.emitReport(report);
|
|
}
|
|
}
|
|
|
|
return N;
|
|
}
|
|
|
|
void RetainCountChecker::checkEndFunction(CheckerContext &Ctx) const {
|
|
ProgramStateRef state = Ctx.getState();
|
|
RefBindingsTy B = state->get<RefBindings>();
|
|
ExplodedNode *Pred = Ctx.getPredecessor();
|
|
|
|
// Don't process anything within synthesized bodies.
|
|
const LocationContext *LCtx = Pred->getLocationContext();
|
|
if (LCtx->getAnalysisDeclContext()->isBodyAutosynthesized()) {
|
|
assert(LCtx->getParent());
|
|
return;
|
|
}
|
|
|
|
for (RefBindingsTy::iterator I = B.begin(), E = B.end(); I != E; ++I) {
|
|
state = handleAutoreleaseCounts(state, Pred, /*Tag=*/0, Ctx,
|
|
I->first, I->second);
|
|
if (!state)
|
|
return;
|
|
}
|
|
|
|
// If the current LocationContext has a parent, don't check for leaks.
|
|
// We will do that later.
|
|
// FIXME: we should instead check for imbalances of the retain/releases,
|
|
// and suggest annotations.
|
|
if (LCtx->getParent())
|
|
return;
|
|
|
|
B = state->get<RefBindings>();
|
|
SmallVector<SymbolRef, 10> Leaked;
|
|
|
|
for (RefBindingsTy::iterator I = B.begin(), E = B.end(); I != E; ++I)
|
|
state = handleSymbolDeath(state, I->first, I->second, Leaked);
|
|
|
|
processLeaks(state, Leaked, Ctx, Pred);
|
|
}
|
|
|
|
const ProgramPointTag *
|
|
RetainCountChecker::getDeadSymbolTag(SymbolRef sym) const {
|
|
const CheckerProgramPointTag *&tag = DeadSymbolTags[sym];
|
|
if (!tag) {
|
|
SmallString<64> buf;
|
|
llvm::raw_svector_ostream out(buf);
|
|
out << "Dead Symbol : ";
|
|
sym->dumpToStream(out);
|
|
tag = new CheckerProgramPointTag(this, out.str());
|
|
}
|
|
return tag;
|
|
}
|
|
|
|
void RetainCountChecker::checkDeadSymbols(SymbolReaper &SymReaper,
|
|
CheckerContext &C) const {
|
|
ExplodedNode *Pred = C.getPredecessor();
|
|
|
|
ProgramStateRef state = C.getState();
|
|
RefBindingsTy B = state->get<RefBindings>();
|
|
SmallVector<SymbolRef, 10> Leaked;
|
|
|
|
// Update counts from autorelease pools
|
|
for (SymbolReaper::dead_iterator I = SymReaper.dead_begin(),
|
|
E = SymReaper.dead_end(); I != E; ++I) {
|
|
SymbolRef Sym = *I;
|
|
if (const RefVal *T = B.lookup(Sym)){
|
|
// Use the symbol as the tag.
|
|
// FIXME: This might not be as unique as we would like.
|
|
const ProgramPointTag *Tag = getDeadSymbolTag(Sym);
|
|
state = handleAutoreleaseCounts(state, Pred, Tag, C, Sym, *T);
|
|
if (!state)
|
|
return;
|
|
|
|
// Fetch the new reference count from the state, and use it to handle
|
|
// this symbol.
|
|
state = handleSymbolDeath(state, *I, *getRefBinding(state, Sym), Leaked);
|
|
}
|
|
}
|
|
|
|
if (Leaked.empty()) {
|
|
C.addTransition(state);
|
|
return;
|
|
}
|
|
|
|
Pred = processLeaks(state, Leaked, C, Pred);
|
|
|
|
// Did we cache out?
|
|
if (!Pred)
|
|
return;
|
|
|
|
// Now generate a new node that nukes the old bindings.
|
|
// The only bindings left at this point are the leaked symbols.
|
|
RefBindingsTy::Factory &F = state->get_context<RefBindings>();
|
|
B = state->get<RefBindings>();
|
|
|
|
for (SmallVectorImpl<SymbolRef>::iterator I = Leaked.begin(),
|
|
E = Leaked.end();
|
|
I != E; ++I)
|
|
B = F.remove(B, *I);
|
|
|
|
state = state->set<RefBindings>(B);
|
|
C.addTransition(state, Pred);
|
|
}
|
|
|
|
void RetainCountChecker::printState(raw_ostream &Out, ProgramStateRef State,
|
|
const char *NL, const char *Sep) const {
|
|
|
|
RefBindingsTy B = State->get<RefBindings>();
|
|
|
|
if (B.isEmpty())
|
|
return;
|
|
|
|
Out << Sep << NL;
|
|
|
|
for (RefBindingsTy::iterator I = B.begin(), E = B.end(); I != E; ++I) {
|
|
Out << I->first << " : ";
|
|
I->second.print(Out);
|
|
Out << NL;
|
|
}
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Checker registration.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void ento::registerRetainCountChecker(CheckerManager &Mgr) {
|
|
Mgr.registerChecker<RetainCountChecker>(Mgr.getAnalyzerOptions());
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Implementation of the CallEffects API.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace clang { namespace ento { namespace objc_retain {
|
|
|
|
// This is a bit gross, but it allows us to populate CallEffects without
|
|
// creating a bunch of accessors. This kind is very localized, so the
|
|
// damage of this macro is limited.
|
|
#define createCallEffect(D, KIND)\
|
|
ASTContext &Ctx = D->getASTContext();\
|
|
LangOptions L = Ctx.getLangOpts();\
|
|
RetainSummaryManager M(Ctx, L.GCOnly, L.ObjCAutoRefCount);\
|
|
const RetainSummary *S = M.get ## KIND ## Summary(D);\
|
|
CallEffects CE(S->getRetEffect());\
|
|
CE.Receiver = S->getReceiverEffect();\
|
|
unsigned N = D->param_size();\
|
|
for (unsigned i = 0; i < N; ++i) {\
|
|
CE.Args.push_back(S->getArg(i));\
|
|
}
|
|
|
|
CallEffects CallEffects::getEffect(const ObjCMethodDecl *MD) {
|
|
createCallEffect(MD, Method);
|
|
return CE;
|
|
}
|
|
|
|
CallEffects CallEffects::getEffect(const FunctionDecl *FD) {
|
|
createCallEffect(FD, Function);
|
|
return CE;
|
|
}
|
|
|
|
#undef createCallEffect
|
|
|
|
}}}
|