Namespaces
namespace	utils

Classes
struct	AccessPath
	Represents the storage location being borrowed, e.g., a specific stack variable. More...
class	DataflowAnalysis
	A generic, policy-based driver for dataflow analyses. More...
class	ExpireFact
class	Fact
	An abstract base class for a single, atomic lifetime-relevant event. More...
class	FactManager
class	FactsGenerator
class	IssueFact
struct	LifetimeFactory
	An object to hold the factories for immutable collections, ensuring that all created states share the same underlying memory management. More...
class	LifetimeSafetyAnalysis
	Running the lifetime safety analysis and querying its results. More...
struct	LivenessInfo
	Information about why an origin is live at a program point. More...
class	LiveOriginsAnalysis
class	Loan
	An abstract base class for a single "Loan" which represents lending a storage in memory. More...
class	LoanManager
	Manages the creation, storage and retrieval of loans. More...
class	LoanPropagationAnalysis
struct	Origin
	An Origin is a symbolic identifier that represents the set of possible loans a pointer-like object could hold at any given time. More...
class	OriginEscapesFact
class	OriginFlowFact
class	OriginList
	A list of origins representing levels of indirection for pointer-like types. More...
class	OriginManager
	Manages the creation, storage, and retrieval of origins for pointer-like variables and expressions. More...
class	PathLoan
	PathLoan represents lending a storage location that is visible within the function's scope (e.g., a local variable on stack). More...
class	PlaceholderLoan
	A placeholder loan held by a function parameter, representing a borrow from the caller's scope. More...
class	TestPointFact
	A dummy-fact used to mark a specific point in the code for testing. More...
class	UseFact

Typedefs
using	FactID = utils::ID<struct FactTag>
using	ProgramPoint = const Fact *
	A ProgramPoint identifies a location in the CFG by pointing to a specific Fact.
using	CausingFactType
using	LivenessMap = llvm::ImmutableMap<OriginID, LivenessInfo>
using	LoanSet = llvm::ImmutableSet<LoanID>
using	OriginLoanMap = llvm::ImmutableMap<OriginID, LoanSet>
using	LoanID = utils::ID<struct LoanTag>
using	OriginID = utils::ID<struct OriginTag>

Enumerations
enum class	LivenessKind : uint8_t { Dead , Maybe , Must }
enum class	Direction { Forward , Backward }

Functions
void	runLifetimeChecker (const LoanPropagationAnalysis &LoanPropagation, const LiveOriginsAnalysis &LiveOrigins, const FactManager &FactMgr, AnalysisDeclContext &ADC, LifetimeSafetyReporter *Reporter)
	Runs the lifetime checker, which detects use-after-free errors by examining loan expiration points and checking if any live origins hold the expired loan.
void	collectLifetimeStats (AnalysisDeclContext &AC, OriginManager &OM, LifetimeSafetyStats &Stats)
llvm::raw_ostream &	operator<< (llvm::raw_ostream &OS, LoanID ID)
llvm::raw_ostream &	operator<< (llvm::raw_ostream &OS, OriginID ID)
bool	hasOrigins (QualType QT)
bool	hasOrigins (const Expr *E)
	Determines if an expression has origins that need to be tracked.
bool	doesDeclHaveStorage (const ValueDecl *D)
	Returns true if the declaration has its own storage that can be borrowed.
static Confidence	livenessKindToConfidence (LivenessKind K)
static const PathLoan *	createLoan (FactManager &FactMgr, const DeclRefExpr *DRE)
	Creates a loan for the storage path of a given declaration reference.
static OriginList *	getRValueOrigins (const Expr E, OriginList List)
	Simulates LValueToRValue conversion by peeling the outer lvalue origin if the expression is a GLValue.
static void	DebugOnlyFunction (AnalysisDeclContext &AC, const CFG &Cfg, FactManager &FactMgr)
static llvm::BitVector	computePersistentOrigins (const FactManager &FactMgr, const CFG &C)

Typedef Documentation

◆ CausingFactType

using clang::lifetimes::internal::CausingFactType

Initial value:

::llvm::PointerUnion<const UseFact *, const OriginEscapesFact *>

Definition at line 34 of file LiveOrigins.h.

◆ FactID

using clang::lifetimes::internal::FactID = utils::ID<struct FactTag>

Definition at line 28 of file Facts.h.

◆ LivenessMap

using clang::lifetimes::internal::LivenessMap = llvm::ImmutableMap<OriginID, LivenessInfo>

Definition at line 76 of file LiveOrigins.h.

◆ LoanID

using clang::lifetimes::internal::LoanID = utils::ID<struct LoanTag>

Definition at line 23 of file Loans.h.

◆ LoanSet

using clang::lifetimes::internal::LoanSet = llvm::ImmutableSet<LoanID>

Definition at line 29 of file LoanPropagation.h.

◆ OriginID

using clang::lifetimes::internal::OriginID = utils::ID<struct OriginTag>

Definition at line 26 of file Origins.h.

◆ OriginLoanMap

using clang::lifetimes::internal::OriginLoanMap = llvm::ImmutableMap<OriginID, LoanSet>

Definition at line 30 of file LoanPropagation.h.

◆ ProgramPoint

using clang::lifetimes::internal::ProgramPoint = const Fact *

A ProgramPoint identifies a location in the CFG by pointing to a specific Fact.

identified by a lifetime-related event (Fact).

A ProgramPoint has "after" semantics: it represents the location immediately after its corresponding Fact.

Definition at line 82 of file Facts.h.

Enumeration Type Documentation

◆ Direction

enum class clang::lifetimes::internal::Direction

strong

Enumerator
Forward
Backward

Definition at line 29 of file Dataflow.h.

◆ LivenessKind

enum class clang::lifetimes::internal::LivenessKind : uint8_t

strong

Enumerator
Dead
Maybe
Must

Definition at line 37 of file LiveOrigins.h.

Function Documentation

◆ collectLifetimeStats()

void clang::lifetimes::internal::collectLifetimeStats	(	AnalysisDeclContext &	AC,
		OriginManager &	OM,
		LifetimeSafetyStats &	Stats )

Definition at line 96 of file LifetimeSafety.cpp.

References clang::lifetimes::internal::OriginManager::collectMissingOrigins(), and clang::AnalysisDeclContext::getBody().

◆ computePersistentOrigins()

llvm::BitVector clang::lifetimes::internal::computePersistentOrigins	(	const FactManager &	FactMgr,
		const CFG &	C )

static

Definition at line 29 of file LoanPropagation.cpp.

◆ createLoan()

const PathLoan * clang::lifetimes::internal::createLoan	(	FactManager &	FactMgr,
		const DeclRefExpr *	DRE )

static

Creates a loan for the storage path of a given declaration reference.

This function should be called whenever a DeclRefExpr represents a borrow.

Parameters

DRE	The declaration reference expression that initiates the borrow.

Returns: The new Loan on success, nullptr otherwise.

Definition at line 64 of file FactsGenerator.cpp.

References clang::lifetimes::internal::LoanManager::createLoan(), clang::DeclRefExpr::getDecl(), and clang::lifetimes::internal::FactManager::getLoanMgr().

Referenced by clang::lifetimes::internal::FactsGenerator::VisitDeclRefExpr().

◆ DebugOnlyFunction()

void clang::lifetimes::internal::DebugOnlyFunction	(	AnalysisDeclContext &	AC,
		const CFG &	Cfg,
		FactManager &	FactMgr )

static

Definition at line 37 of file LifetimeSafety.cpp.

References clang::CFG::dump(), clang::lifetimes::internal::FactManager::dump(), clang::Decl::dumpColor(), clang::AnalysisDeclContext::getASTContext(), clang::AnalysisDeclContext::getDecl(), and clang::ASTContext::getLangOpts().

Referenced by clang::lifetimes::internal::LifetimeSafetyAnalysis::run().

◆ doesDeclHaveStorage()

bool clang::lifetimes::internal::doesDeclHaveStorage ( const ValueDecl * D )

Returns true if the declaration has its own storage that can be borrowed.

References generally have no storage - they are aliases to other storage. For example: int x; // has storage (can issue loans to x's storage) int& r = x; // no storage (r is an alias to x's storage) int* p; // has storage (the pointer variable p itself has storage)

TODO: Handle lifetime extension. References initialized by temporaries can have storage when the temporary's lifetime is extended: const int& r = 42; // temporary has storage, lifetime extended Foo&& f = Foo{}; // temporary has storage, lifetime extended Currently, this function returns false for all reference types.

Definition at line 84 of file Origins.cpp.

References clang::ValueDecl::getType(), and clang::Type::isReferenceType().

Referenced by clang::lifetimes::internal::OriginManager::getOrCreateList(), and clang::lifetimes::internal::FactsGenerator::VisitDeclRefExpr().

◆ getRValueOrigins()

OriginList * clang::lifetimes::internal::getRValueOrigins	(	const Expr *	E,
		OriginList *	List )

static

Simulates LValueToRValue conversion by peeling the outer lvalue origin if the expression is a GLValue.

For pointer/view GLValues, this strips the origin representing the storage location to get the origins of the pointed-to value.

Example: For View& v, returns the origin of what v points to, not v's storage.

Definition at line 107 of file FactsGenerator.cpp.

References clang::Expr::isGLValue(), and clang::lifetimes::internal::OriginList::peelOuterOrigin().

Referenced by clang::lifetimes::internal::FactsGenerator::VisitImplicitCastExpr(), and clang::lifetimes::internal::FactsGenerator::VisitMaterializeTemporaryExpr().

◆ hasOrigins() [1/2]

bool clang::lifetimes::internal::hasOrigins ( const Expr * E )

Determines if an expression has origins that need to be tracked.

An expression has origins if:

It's a glvalue (has addressable storage), OR
Its type is pointer-like (pointer, reference, or gsl::Pointer)

Examples:

int x; x : has origin (glvalue)
int* p; p : has 2 origins (1 for glvalue and 1 for pointer type)
std::string_view{} : has 1 origin (prvalue of pointer type)
42 : no origin (prvalue of non-pointer type)
x + y : (where x, y are int) → no origin (prvalue of non-pointer type)

Definition at line 67 of file Origins.cpp.

References clang::Expr::getType(), hasOrigins(), and clang::Expr::isGLValue().

◆ hasOrigins() [2/2]

bool clang::lifetimes::internal::hasOrigins ( QualType QT )

Definition at line 51 of file Origins.cpp.

References clang::lifetimes::isGslPointerType(), and clang::Type::isPointerOrReferenceType().

Referenced by clang::lifetimes::internal::OriginManager::getOrCreateList(), clang::lifetimes::internal::OriginManager::getOrCreateList(), hasOrigins(), clang::lifetimes::internal::FactsGenerator::VisitConditionalOperator(), clang::lifetimes::internal::FactsGenerator::VisitCXXOperatorCallExpr(), and clang::lifetimes::internal::FactsGenerator::VisitInitListExpr().

◆ livenessKindToConfidence()

Confidence clang::lifetimes::internal::livenessKindToConfidence ( LivenessKind K )

static

Definition at line 30 of file Checker.cpp.

References Dead, clang::lifetimes::Definite, clang::lifetimes::Maybe, Maybe, Must, and clang::lifetimes::None.

◆ operator<<() [1/2]

llvm::raw_ostream & clang::lifetimes::internal::operator<<	(	llvm::raw_ostream &	OS,
		LoanID	ID )

inline

Definition at line 24 of file Loans.h.

◆ operator<<() [2/2]

llvm::raw_ostream & clang::lifetimes::internal::operator<<	(	llvm::raw_ostream &	OS,
		OriginID	ID )

inline

Definition at line 28 of file Origins.h.

◆ runLifetimeChecker()

void clang::lifetimes::internal::runLifetimeChecker	(	const LoanPropagationAnalysis &	LoanPropagation,
		const LiveOriginsAnalysis &	LiveOrigins,
		const FactManager &	FactMgr,
		AnalysisDeclContext &	ADC,
		LifetimeSafetyReporter *	Reporter )

Runs the lifetime checker, which detects use-after-free errors by examining loan expiration points and checking if any live origins hold the expired loan.

Definition at line 212 of file Checker.cpp.

Referenced by clang::lifetimes::internal::LifetimeSafetyAnalysis::run().

Namespaces

Classes

Typedefs

Enumerations

Functions

Typedef Documentation

◆ CausingFactType

◆ FactID

◆ LivenessMap

◆ LoanID

◆ LoanSet

◆ OriginID

◆ OriginLoanMap

◆ ProgramPoint

Enumeration Type Documentation

◆ Direction

◆ LivenessKind

Function Documentation

◆ collectLifetimeStats()

◆ computePersistentOrigins()

◆ createLoan()

◆ DebugOnlyFunction()

◆ doesDeclHaveStorage()

◆ getRValueOrigins()

◆ hasOrigins() [1/2]

◆ hasOrigins() [2/2]

◆ livenessKindToConfidence()

◆ operator<<() [1/2]

◆ operator<<() [2/2]

◆ runLifetimeChecker()