Dataflow Directional Tag Classes. More...

Classes
class	AggregateStorageLocation
	A storage location which is subdivided into smaller storage locations that can be traced independently by abstract interpretation. More...

class	AtomicBoolValue
	Models an atomic boolean. More...

struct	backward_analysis_tag

struct	BooleanFormula
	A boolean formula in conjunctive normal form. More...

class	BoolValue
	Models a boolean. More...

class	ChromiumCheckModel
	Models the behavior of Chromium's CHECK, DCHECK, etc. More...

class	ConjunctionValue
	Models a boolean conjunction. More...

class	ControlFlowContext
	Holds CFG and other derived context that is needed to perform dataflow analysis. More...

class	DataflowAnalysis
	Base class template for dataflow analyses built on a single lattice type. More...

class	DataflowAnalysisContext
	Owns objects that encompass the state of a program and stores context that is used during dataflow analysis. More...

struct	DataflowAnalysisState

class	DataflowModel
	Abstract base class for dataflow "models": reusable analysis components that model a particular aspect of program semantics in the `Environment`. More...

class	DisjunctionValue
	Models a boolean disjunction. More...

class	Environment
	Holds the state of the program (store and heap) at a given program point. More...

struct	forward_analysis_tag

class	IndirectionValue
	Base class for values that refer to storage locations. More...

class	IntegerValue
	Models an integer. More...

class	MapLattice
	A lattice that maps keys to individual lattice elements. More...

class	MatchSwitchBuilder
	Collects cases of a "match switch": a collection of matchers paired with callbacks, which together define a switch that can be applied to a `Stmt`. More...

class	NegationValue
	Models a boolean negation. More...

class	PointerValue
	Models a symbolic pointer. Specifically, any value of type `T*`. More...

class	ReferenceValue
	Models a dereferenced pointer. More...

class	ScalarStorageLocation
	A storage location that is not subdivided further for the purposes of abstract interpretation. More...

class	Solver
	An interface for a SAT solver that can be used by dataflow analyses. More...

class	SourceLocationsLattice
	Lattice for dataflow analysis that keeps track of a set of source locations. More...

class	StmtToEnvMap
	Maps statements to the environments of basic blocks that contain them. More...

class	StmtToEnvMapImpl

class	StorageLocation
	Base class for elements of the local variable store and of the heap. More...

class	StructValue
	Models a value of `struct` or `class` type, with a flat map of fields to child storage locations, containing all accessible members of base struct and class types. More...

class	TerminatorVisitor
	Extends the flow condition of an environment based on a terminator statement. More...

struct	TransferState
	A common form of state shared between the cases of a transfer function. More...

class	TransferVisitor

class	TypeErasedDataflowAnalysis
	Type-erased base class for dataflow analyses built on a single lattice type. More...

struct	TypeErasedDataflowAnalysisState
	Type-erased model of the program at a given program point. More...

struct	TypeErasedLattice
	Type-erased lattice element container. More...

class	UncheckedOptionalAccessModel
	Dataflow analysis that discovers unsafe accesses of optional values and adds the respective source locations to the lattice. More...

struct	UncheckedOptionalAccessModelOptions

class	Value
	Base class for all values computed by abstract interpretation. More...

class	WatchedLiteralsSolver
	A SAT solver that is an implementation of Algorithm D from Knuth's The Art of Computer Programming Volume 4: Satisfiability, Fascicle 6. More...

class	WatchedLiteralsSolverImpl

Typedefs
template<typename ElementLattice >
using	VarMapLattice = MapLattice< const clang::VarDecl *, ElementLattice >
	Convenience alias that captures the common use of map lattices to model in-scope variables. More...

template<typename State >
using	MatchSwitch = std::function< void(const Stmt &, ASTContext &, State &)>
	Matches against `Stmt` and, based on its structure, dispatches to an appropriate handler. More...

using	Variable = uint32_t
	Boolean variables are represented as positive integers. More...

using	Literal = uint32_t
	Literals are represented as positive integers. More...

using	ClauseID = uint32_t
	Clause identifiers are represented as positive integers. More...

Enumerations
enum	SkipPast { SkipPast::None, SkipPast::Reference, SkipPast::ReferenceThenPointer }
	Indicates what kind of indirections should be skipped past when retrieving storage locations or values. More...

enum	LatticeJoinEffect { LatticeJoinEffect::Unchanged, LatticeJoinEffect::Changed }
	Effect indicating whether a lattice join operation resulted in a new value. More...

Functions
template<typename AnalysisT >
llvm::Expected< std::vector< llvm::Optional< DataflowAnalysisState< typename AnalysisT::Lattice > > > >	runDataflowAnalysis (const ControlFlowContext &CFCtx, AnalysisT &Analysis, const Environment &InitEnv)
	Performs dataflow analysis and returns a mapping from basic block IDs to dataflow analysis states that model the respective basic blocks. More...

const Expr &	ignoreCFGOmittedNodes (const Expr &E)
	Skip past nodes that the CFG does not emit. More...

const Stmt &	ignoreCFGOmittedNodes (const Stmt &S)

template<typename Key , typename ElementLattice >
std::ostream &	operator<< (std::ostream &Os, const clang::dataflow::MapLattice< Key, ElementLattice > &M)

template<typename ElementLattice >
std::ostream &	operator<< (std::ostream &Os, const clang::dataflow::VarMapLattice< ElementLattice > &M)

std::string	DebugString (const SourceLocationsLattice &Lattice, const ASTContext &Context)
	Returns a string that represents the source locations of the lattice. More...

void	transfer (const StmtToEnvMap &StmtToEnv, const Stmt &S, Environment &Env)
	Evaluates `S` and updates `Env` accordingly. More...

TypeErasedDataflowAnalysisState	transferBlock (const ControlFlowContext &CFCtx, std::vector< llvm::Optional< TypeErasedDataflowAnalysisState >> &BlockStates, const CFGBlock &Block, const Environment &InitEnv, TypeErasedDataflowAnalysis &Analysis, std::function< void(const CFGStmt &, const TypeErasedDataflowAnalysisState &)> HandleTransferredStmt=nullptr)
	Transfers the state of a basic block by evaluating each of its statements in the context of `Analysis` and the states of its predecessors that are available in `BlockStates`. More...

llvm::Expected< std::vector< llvm::Optional< TypeErasedDataflowAnalysisState > > >	runTypeErasedDataflowAnalysis (const ControlFlowContext &CFCtx, TypeErasedDataflowAnalysis &Analysis, const Environment &InitEnv)
	Performs dataflow analysis and returns a mapping from basic block IDs to dataflow analysis states that model the respective basic blocks. More...

static llvm::DenseMap< const Stmt , const CFGBlock >	buildStmtToBasicBlockMap (const CFG &Cfg)
	Returns a map from statements to basic blocks that contain them. More...

static std::pair< BoolValue , BoolValue >	makeCanonicalBoolValuePair (BoolValue &LHS, BoolValue &RHS)

template<typename K , typename V >
llvm::DenseMap< K, V >	intersectDenseMaps (const llvm::DenseMap< K, V > &Map1, const llvm::DenseMap< K, V > &Map2)
	Returns a map consisting of key-value entries that are present in both maps. More...

static bool	equivalentValues (QualType Type, Value Val1, const Environment &Env1, Value Val2, const Environment &Env2, Environment::ValueModel &Model)
	Returns true if and only if `Val1` is equivalent to `Val2`. More...

static Value *	mergeDistinctValues (QualType Type, Value Val1, const Environment &Env1, Value Val2, const Environment &Env2, Environment &MergedEnv, Environment::ValueModel &Model)
	Attempts to merge distinct values `Val1` and `Val2` in `Env1` and `Env2`, respectively, of the same type `Type`. More...

static void	initGlobalVar (const VarDecl &D, Environment &Env)
	Initializes a global storage value. More...

static void	initGlobalVar (const Decl &D, Environment &Env)
	Initializes a global storage value. More...

static void	initGlobalVars (const Stmt &S, Environment &Env)
	Initializes global storage values that are declared or referenced from sub-statements of `S`. More...

static void	getFieldsFromClassHierarchy (QualType Type, bool IgnorePrivateFields, llvm::DenseSet< const FieldDecl * > &Fields)

static llvm::DenseSet< const FieldDecl * >	getAccessibleObjectFields (QualType Type)
	Gets the set of all fields accesible from the type. More...

bool	isCheckLikeMethod (llvm::SmallDenseSet< const CXXMethodDecl * > &CheckDecls, const CXXMethodDecl &D)
	Determines whether `D` is one of the methods used to implement Chromium's `CHECK` macros. More...

static BoolValue &	evaluateBooleanEquality (const Expr &LHS, const Expr &RHS, Environment &Env)

static int	blockIndexInPredecessor (const CFGBlock &Pred, const CFGBlock &Block)
	Returns the index of `Block` in the successors of `Pred`. More...

static TypeErasedDataflowAnalysisState	computeBlockInputState (const ControlFlowContext &CFCtx, std::vector< llvm::Optional< TypeErasedDataflowAnalysisState >> &BlockStates, const CFGBlock &Block, const Environment &InitEnv, TypeErasedDataflowAnalysis &Analysis)
	Computes the input state for a given basic block by joining the output states of its predecessors. More...

static void	transferCFGStmt (const ControlFlowContext &CFCtx, llvm::ArrayRef< llvm::Optional< TypeErasedDataflowAnalysisState >> BlockStates, const CFGStmt &CfgStmt, TypeErasedDataflowAnalysis &Analysis, TypeErasedDataflowAnalysisState &State, std::function< void(const CFGStmt &, const TypeErasedDataflowAnalysisState &)> HandleTransferredStmt)
	Transfers `State` by evaluating `CfgStmt` in the context of `Analysis`. More...

static void	transferCFGInitializer (const CFGInitializer &CfgInit, TypeErasedDataflowAnalysisState &State)
	Transfers `State` by evaluating `CfgInit`. More...

static constexpr Literal	posLit (Variable V)
	Returns the positive literal `V`. More...

static constexpr Literal	negLit (Variable V)
	Returns the negative literal `!V`. More...

static constexpr Literal	notLit (Literal L)
	Returns the negated literal `!L`. More...

static constexpr Variable	var (Literal L)
	Returns the variable of `L`. More...

BooleanFormula	buildBooleanFormula (const llvm::DenseSet< BoolValue * > &Vals)
	Converts the conjunction of `Vals` into a formula in conjunctive normal form where each clause has at least one and at most three literals. More...

Variables
static constexpr int	MaxCompositeValueDepth = 3

static constexpr int	MaxCompositeValueSize = 1000

static constexpr Variable	NullVar = 0
	A null boolean variable is used as a placeholder in various data structures and algorithms. More...

static constexpr Literal	NullLit = 0
	A null literal is used as a placeholder in various data structures and algorithms. More...

static constexpr ClauseID	NullClause = 0
	A null clause identifier is used as a placeholder in various data structures and algorithms. More...

Detailed Description

Dataflow Directional Tag Classes.

These are used for tag dispatching within the dataflow solver/transfer functions to determine what direction a dataflow analysis flows.

Typedef Documentation

◆ ClauseID

using clang::dataflow::ClauseID = typedef uint32_t

Clause identifiers are represented as positive integers.

Definition at line 74 of file WatchedLiteralsSolver.cpp.

◆ Literal

using clang::dataflow::Literal = typedef uint32_t

Literals are represented as positive integers.

Specifically, for a boolean variable V that is represented as the positive integer I, the positive literal V is represented as the integer 2*I and the negative literal !V is represented as the integer 2*I+1.

Definition at line 55 of file WatchedLiteralsSolver.cpp.

◆ MatchSwitch

template<typename State >

using clang::dataflow::MatchSwitch = typedef std::function<void(const Stmt &, ASTContext &, State &)>

Matches against Stmt and, based on its structure, dispatches to an appropriate handler.

Definition at line 50 of file MatchSwitch.h.

◆ Variable

using clang::dataflow::Variable = typedef uint32_t

Boolean variables are represented as positive integers.

Definition at line 45 of file WatchedLiteralsSolver.cpp.

◆ VarMapLattice

template<typename ElementLattice >

using clang::dataflow::VarMapLattice = typedef MapLattice<const clang::VarDecl *, ElementLattice>

Convenience alias that captures the common use of map lattices to model in-scope variables.

Definition at line 109 of file MapLattice.h.

Enumeration Type Documentation

◆ LatticeJoinEffect

enum clang::dataflow::LatticeJoinEffect

strong

Effect indicating whether a lattice join operation resulted in a new value.

Enumerator
Unchanged
Changed

Definition at line 21 of file DataflowLattice.h.

◆ SkipPast

enum clang::dataflow::SkipPast

strong

Indicates what kind of indirections should be skipped past when retrieving storage locations or values.

FIXME: Consider renaming this or replacing it with a more appropriate model. See the discussion in https://reviews.llvm.org/D116596 for context.

Enumerator
None	No indirections should be skipped past.
Reference	An optional reference should be skipped past.
ReferenceThenPointer	An optional reference should be skipped past, then an optional pointer should be skipped past.

Definition at line 41 of file DataflowEnvironment.h.

Function Documentation

◆ blockIndexInPredecessor()

static int clang::dataflow::blockIndexInPredecessor	(	const CFGBlock &	Pred,
		const CFGBlock &	Block
	)

static

Returns the index of Block in the successors of Pred.

Definition at line 62 of file TypeErasedDataflowAnalysis.cpp.

References clang::Block, clang::CFGBlock::succ_begin(), and clang::CFGBlock::succs().

Referenced by computeBlockInputState().

◆ buildBooleanFormula()

BooleanFormula clang::dataflow::buildBooleanFormula ( const llvm::DenseSet< BoolValue * > & Vals )

Converts the conjunction of Vals into a formula in conjunctive normal form where each clause has at least one and at most three literals.

Definition at line 174 of file WatchedLiteralsSolver.cpp.

References clang::dataflow::BooleanFormula::addClause(), negLit(), and posLit().

◆ buildStmtToBasicBlockMap()

static llvm::DenseMap<const Stmt *, const CFGBlock *> clang::dataflow::buildStmtToBasicBlockMap ( const CFG & Cfg )

static

Returns a map from statements to basic blocks that contain them.

Definition at line 28 of file ControlFlowContext.cpp.

References clang::Block.

◆ computeBlockInputState()

static TypeErasedDataflowAnalysisState clang::dataflow::computeBlockInputState	(	const ControlFlowContext &	CFCtx,
		std::vector< llvm::Optional< TypeErasedDataflowAnalysisState >> &	BlockStates,
		const CFGBlock &	Block,
		const Environment &	InitEnv,
		TypeErasedDataflowAnalysis &	Analysis
	)

static

Computes the input state for a given basic block by joining the output states of its predecessors.

Requirements:

All predecessors of Block except those with loop back edges must have already been transferred. States in BlockStates that are set to llvm::None represent basic blocks that are not evaluated yet.

Definition at line 150 of file TypeErasedDataflowAnalysis.cpp.

References clang::dataflow::TypeErasedDataflowAnalysis::applyBuiltinTransfer(), clang::Block, blockIndexInPredecessor(), clang::dataflow::TypeErasedDataflowAnalysisState::Env, clang::dataflow::ControlFlowContext::getStmtToBlock(), clang::dataflow::TypeErasedDataflowAnalysis::joinTypeErased(), clang::dataflow::TypeErasedDataflowAnalysisState::Lattice, clang::dataflow::TypeErasedDataflowAnalysis::typeErasedInitialElement(), and clang::StmtVisitorBase< Ptr, ImplClass, RetTy, ParamTys >::Visit().

Referenced by transferBlock().

◆ DebugString()

std::string clang::dataflow::DebugString	(	const SourceLocationsLattice &	Lattice,
		const ASTContext &	Context
	)

Returns a string that represents the source locations of the lattice.

Definition at line 33 of file SourceLocationsLattice.cpp.

References clang::dataflow::SourceLocationsLattice::getSourceLocations(), and string().

◆ equivalentValues()

static bool clang::dataflow::equivalentValues	(	QualType	Type,
		Value *	Val1,
		const Environment &	Env1,
		Value *	Val2,
		const Environment &	Env2,
		Environment::ValueModel &	Model
	)

static

Returns true if and only if Val1 is equivalent to Val2.

Definition at line 54 of file DataflowEnvironment.cpp.

References clang::dataflow::Environment::ValueModel::compareEquivalent().

Referenced by clang::dataflow::Environment::equivalentTo().

◆ evaluateBooleanEquality()

static BoolValue& clang::dataflow::evaluateBooleanEquality	(	const Expr &	LHS,
		const Expr &	RHS,
		Environment &	Env
	)

static

Definition at line 36 of file Transfer.cpp.

References clang::dataflow::Environment::getValue(), clang::dataflow::Environment::makeAtomicBoolValue(), clang::dataflow::Environment::makeIff(), and Reference.

◆ getAccessibleObjectFields()

static llvm::DenseSet<const FieldDecl *> clang::dataflow::getAccessibleObjectFields ( QualType Type )

static

Gets the set of all fields accesible from the type.

FIXME: Does not precisely handle non-virtual diamond inheritance. A single field decl will be modeled for all instances of the inherited field.

Definition at line 180 of file DataflowEnvironment.cpp.

References getFieldsFromClassHierarchy().

Referenced by clang::dataflow::Environment::createStorageLocation(), and clang::dataflow::Environment::setValue().

◆ getFieldsFromClassHierarchy()

static void clang::dataflow::getFieldsFromClassHierarchy	(	QualType	Type,
		bool	IgnorePrivateFields,
		llvm::DenseSet< const FieldDecl * > &	Fields
	)

static

Definition at line 152 of file DataflowEnvironment.cpp.

References clang::AS_none, clang::AS_private, clang::RecordDecl::fields(), clang::Type::getAsCXXRecordDecl(), clang::Type::getAsRecordDecl(), clang::TagDecl::isClass(), clang::Type::isDependentType(), clang::Type::isIncompleteType(), and clang::Type::isRecordType().

Referenced by getAccessibleObjectFields().

◆ ignoreCFGOmittedNodes() [1/2]

const Expr & clang::dataflow::ignoreCFGOmittedNodes ( const Expr & E )

Skip past nodes that the CFG does not emit.

These nodes are invisible to flow-sensitive analysis, and should be ignored as they will effectively not exist.

ParenExpr - The CFG takes the operator precedence into account, but otherwise omits the node afterwards.
ExprWithCleanups - The CFG will generate the appropriate calls to destructors and then omit the node.

Definition at line 162 of file DataflowAnalysisContext.cpp.

Referenced by clang::dataflow::DataflowAnalysisContext::getStorageLocation(), clang::dataflow::Environment::getStorageLocation(), clang::dataflow::DataflowAnalysisContext::setStorageLocation(), and clang::dataflow::Environment::setStorageLocation().

◆ ignoreCFGOmittedNodes() [2/2]

const Stmt & clang::dataflow::ignoreCFGOmittedNodes ( const Stmt & S )

Definition at line 173 of file DataflowAnalysisContext.cpp.

◆ initGlobalVar() [1/2]

static void clang::dataflow::initGlobalVar	(	const Decl &	D,
		Environment &	Env
	)

static

Initializes a global storage value.

Definition at line 122 of file DataflowEnvironment.cpp.

References initGlobalVar(), and V.

◆ initGlobalVar() [2/2]

static void clang::dataflow::initGlobalVar	(	const VarDecl &	D,
		Environment &	Env
	)

static

Initializes a global storage value.

Definition at line 110 of file DataflowEnvironment.cpp.

References clang::dataflow::Environment::createStorageLocation(), clang::dataflow::Environment::createValue(), clang::dataflow::Environment::getStorageLocation(), clang::ValueDecl::getType(), clang::VarDecl::hasGlobalStorage(), None, clang::dataflow::Environment::setStorageLocation(), and clang::dataflow::Environment::setValue().

Referenced by initGlobalVar().

◆ initGlobalVars()

static void clang::dataflow::initGlobalVars	(	const Stmt &	S,
		Environment &	Env
	)

static

Initializes global storage values that are declared or referenced from sub-statements of S.

Definition at line 131 of file DataflowEnvironment.cpp.

Referenced by clang::dataflow::Environment::Environment().

◆ intersectDenseMaps()

template<typename K , typename V >

llvm::DenseMap<K, V> clang::dataflow::intersectDenseMaps	(	const llvm::DenseMap< K, V > &	Map1,
		const llvm::DenseMap< K, V > &	Map2
	)

Returns a map consisting of key-value entries that are present in both maps.

Definition at line 42 of file DataflowEnvironment.cpp.

Referenced by clang::dataflow::Environment::join().

◆ isCheckLikeMethod()

bool clang::dataflow::isCheckLikeMethod	(	llvm::SmallDenseSet< const CXXMethodDecl * > &	CheckDecls,
		const CXXMethodDecl &	D
	)

Determines whether D is one of the methods used to implement Chromium's CHECK macros.

Populates CheckDecls, if empty.

Definition at line 19 of file ChromiumCheckModel.cpp.

References clang::Decl::getDeclContext(), clang::NamedDecl::getDeclName(), clang::NamedDecl::getName(), clang::CXXMethodDecl::getParent(), clang::DeclarationName::isIdentifier(), clang::CXXMethodDecl::isStatic(), and clang::CXXRecordDecl::methods().

Referenced by clang::dataflow::ChromiumCheckModel::transfer().

◆ makeCanonicalBoolValuePair()

static std::pair<BoolValue , BoolValue > clang::dataflow::makeCanonicalBoolValuePair	(	BoolValue &	LHS,
		BoolValue &	RHS
	)

static

Definition at line 26 of file DataflowAnalysisContext.cpp.

Referenced by clang::dataflow::DataflowAnalysisContext::getOrCreateConjunctionValue(), and clang::dataflow::DataflowAnalysisContext::getOrCreateDisjunctionValue().

◆ mergeDistinctValues()

static Value* clang::dataflow::mergeDistinctValues	(	QualType	Type,
		Value *	Val1,
		const Environment &	Env1,
		Value *	Val2,
		const Environment &	Env2,
		Environment &	MergedEnv,
		Environment::ValueModel &	Model
	)

static

Attempts to merge distinct values Val1 and Val2 in Env1 and Env2, respectively, of the same type Type.

Merging generally produces a single value that (soundly) approximates the two inputs, although the actual meaning depends on Model.

Definition at line 75 of file DataflowEnvironment.cpp.

References clang::dataflow::Environment::createValue(), clang::dataflow::Environment::getFlowConditionToken(), clang::dataflow::Environment::makeAnd(), clang::dataflow::Environment::makeOr(), and clang::dataflow::Environment::ValueModel::merge().

Referenced by clang::dataflow::Environment::join().

◆ negLit()

static constexpr Literal clang::dataflow::negLit ( Variable V )

staticconstexpr

Returns the negative literal !V.

Definition at line 65 of file WatchedLiteralsSolver.cpp.

References V.

Referenced by buildBooleanFormula(), clang::dataflow::WatchedLiteralsSolverImpl::solve(), and clang::dataflow::WatchedLiteralsSolverImpl::WatchedLiteralsSolverImpl().

◆ notLit()

static constexpr Literal clang::dataflow::notLit ( Literal L )

staticconstexpr

Returns the negated literal !L.

Definition at line 68 of file WatchedLiteralsSolver.cpp.

◆ operator<<() [1/2]

template<typename Key , typename ElementLattice >

std::ostream& clang::dataflow::operator<<	(	std::ostream &	Os,
		const clang::dataflow::MapLattice< Key, ElementLattice > &	M
	)

Definition at line 113 of file MapLattice.h.

References string().

◆ operator<<() [2/2]

template<typename ElementLattice >

std::ostream& clang::dataflow::operator<<	(	std::ostream &	Os,
		const clang::dataflow::VarMapLattice< ElementLattice > &	M
	)

Definition at line 126 of file MapLattice.h.

References string().

◆ posLit()

static constexpr Literal clang::dataflow::posLit ( Variable V )

staticconstexpr

Returns the positive literal V.

Definition at line 62 of file WatchedLiteralsSolver.cpp.

References V.

Referenced by buildBooleanFormula(), clang::dataflow::WatchedLiteralsSolverImpl::solve(), and clang::dataflow::WatchedLiteralsSolverImpl::WatchedLiteralsSolverImpl().

◆ runDataflowAnalysis()

template<typename AnalysisT >

llvm::Expected<std::vector< llvm::Optional<DataflowAnalysisState<typename AnalysisT::Lattice> > > > clang::dataflow::runDataflowAnalysis	(	const ControlFlowContext &	CFCtx,
		AnalysisT &	Analysis,
		const Environment &	InitEnv
	)

Performs dataflow analysis and returns a mapping from basic block IDs to dataflow analysis states that model the respective basic blocks.

The returned vector, if any, will have the same size as the number of CFG blocks, with indices corresponding to basic block IDs. Returns an error if the dataflow analysis cannot be performed successfully.

Definition at line 116 of file DataflowAnalysis.h.

References runTypeErasedDataflowAnalysis(), and State.

◆ runTypeErasedDataflowAnalysis()

llvm::Expected< std::vector< llvm::Optional< TypeErasedDataflowAnalysisState > > > clang::dataflow::runTypeErasedDataflowAnalysis	(	const ControlFlowContext &	CFCtx,
		TypeErasedDataflowAnalysis &	Analysis,
		const Environment &	InitEnv
	)

Performs dataflow analysis and returns a mapping from basic block IDs to dataflow analysis states that model the respective basic blocks.

Indices of the returned vector correspond to basic block IDs. Returns an error if the dataflow analysis cannot be performed successfully.

Definition at line 314 of file TypeErasedDataflowAnalysis.cpp.

References clang::Block, clang::DataflowWorklistBase< Comp, QueueSize >::dequeue(), clang::ForwardDataflowWorklist::enqueueSuccessors(), clang::dataflow::TypeErasedDataflowAnalysisState::Env, clang::CFGBlock::getBlockID(), clang::dataflow::ControlFlowContext::getCFG(), clang::CFG::getEntry(), clang::dataflow::TypeErasedDataflowAnalysis::isEqualTypeErased(), clang::dataflow::TypeErasedDataflowAnalysisState::Lattice, clang::CFG::size(), transferBlock(), and clang::dataflow::TypeErasedDataflowAnalysis::typeErasedInitialElement().

Referenced by runDataflowAnalysis().

◆ transfer()

void clang::dataflow::transfer	(	const StmtToEnvMap &	StmtToEnv,
		const Stmt &	S,
		Environment &	Env
	)

Evaluates S and updates Env accordingly.

Requirements:

S must not be ParenExpr or ExprWithCleanups.

Definition at line 596 of file Transfer.cpp.

Referenced by clang::dataflow::DataflowAnalysis< UncheckedOptionalAccessModel, SourceLocationsLattice >::transferTypeErased().

◆ transferBlock()

TypeErasedDataflowAnalysisState clang::dataflow::transferBlock	(	const ControlFlowContext &	CFCtx,
		std::vector< llvm::Optional< TypeErasedDataflowAnalysisState >> &	BlockStates,
		const CFGBlock &	Block,
		const Environment &	InitEnv,
		TypeErasedDataflowAnalysis &	Analysis,
		std::function< void(const CFGStmt &, const TypeErasedDataflowAnalysisState &)>	HandleTransferredStmt = `nullptr`
	)

Transfers the state of a basic block by evaluating each of its statements in the context of Analysis and the states of its predecessors that are available in BlockStates.

HandleTransferredStmt (if provided) will be applied to each statement in the block, after it is evaluated.

Requirements:

All predecessors of Block except those with loop back edges must have already been transferred. States in BlockStates that are set to llvm::None represent basic blocks that are not evaluated yet.

Definition at line 285 of file TypeErasedDataflowAnalysis.cpp.

References clang::dataflow::TypeErasedDataflowAnalysis::applyBuiltinTransfer(), clang::Block, computeBlockInputState(), clang::CFGElement::Initializer, State, clang::CFGElement::Statement, transferCFGInitializer(), and transferCFGStmt().

Referenced by runTypeErasedDataflowAnalysis().

◆ transferCFGInitializer()

static void clang::dataflow::transferCFGInitializer	(	const CFGInitializer &	CfgInit,
		TypeErasedDataflowAnalysisState &	State
	)

static

Transfers State by evaluating CfgInit.

Definition at line 251 of file TypeErasedDataflowAnalysis.cpp.

References clang::CFGInitializer::getInitializer(), clang::Initializer, clang::Member, Reference, and State.

Referenced by transferBlock().

◆ transferCFGStmt()

static void clang::dataflow::transferCFGStmt	(	const ControlFlowContext &	CFCtx,
		llvm::ArrayRef< llvm::Optional< TypeErasedDataflowAnalysisState >>	BlockStates,
		const CFGStmt &	CfgStmt,
		TypeErasedDataflowAnalysis &	Analysis,
		TypeErasedDataflowAnalysisState &	State,
		std::function< void(const CFGStmt &, const TypeErasedDataflowAnalysisState &)>	HandleTransferredStmt
	)

static

Transfers State by evaluating CfgStmt in the context of Analysis.

HandleTransferredStmt (if provided) will be applied to CfgStmt, after it is evaluated.

Definition at line 231 of file TypeErasedDataflowAnalysis.cpp.

Referenced by transferBlock().

◆ var()

static constexpr Variable clang::dataflow::var ( Literal L )

staticconstexpr

Returns the variable of L.

Definition at line 71 of file WatchedLiteralsSolver.cpp.

Referenced by clang::Sema::ActOnBlockStmtExpr(), clang::Sema::ActOnForEachDeclStmt(), clang::Sema::CheckCompleteVariableDeclaration(), considerVariable(), drillIntoBlockVariable(), emitArgumentDemotion(), clang::CodeGen::CodeGenFunction::emitAutoVarTypeCleanup(), EmitAutoVarWithLifetime(), clang::CodeGen::CodeGenFunction::emitBlockByrefAddress(), clang::CodeGen::CodeGenFunction::EmitDeclRefLValue(), clang::CodeGen::CodeGenFunction::EmitStaticVarDecl(), clang::CodeGen::CodeGenFunction::GenerateBlockFunction(), clang::CodeGen::CGBlockInfo::getCapture(), clang::CFGImplicitDtor::getDestructorDecl(), clang::Sema::inferObjCARCLifetime(), isAccessedBy(), isBlockVarRef(), isInvalidICRSource(), SetupCleanupBlockActivation(), shouldExtendReceiverForInnerPointerMessage(), clang::arcmt::trans::BlockObjCVariableTraverser::traverseBody(), tryCaptureAsConstant(), and clang::CodeGen::CodeGenFunction::tryEmitAsConstant().

Variable Documentation

◆ MaxCompositeValueDepth

constexpr int clang::dataflow::MaxCompositeValueDepth = 3

staticconstexpr

Definition at line 37 of file DataflowEnvironment.cpp.

◆ MaxCompositeValueSize

constexpr int clang::dataflow::MaxCompositeValueSize = 1000

staticconstexpr

Definition at line 38 of file DataflowEnvironment.cpp.

Referenced by clang::dataflow::Environment::createValue().

◆ NullClause

constexpr ClauseID clang::dataflow::NullClause = 0

staticconstexpr

A null clause identifier is used as a placeholder in various data structures and algorithms.

Definition at line 78 of file WatchedLiteralsSolver.cpp.

◆ NullLit

constexpr Literal clang::dataflow::NullLit = 0

staticconstexpr

A null literal is used as a placeholder in various data structures and algorithms.

Definition at line 59 of file WatchedLiteralsSolver.cpp.

Referenced by clang::dataflow::BooleanFormula::addClause().

◆ NullVar

constexpr Variable clang::dataflow::NullVar = 0

staticconstexpr

A null boolean variable is used as a placeholder in various data structures and algorithms.

Definition at line 49 of file WatchedLiteralsSolver.cpp.

Referenced by clang::dataflow::WatchedLiteralsSolverImpl::WatchedLiteralsSolverImpl().

Classes

Typedefs

Enumerations

Functions

Variables

Detailed Description

Typedef Documentation

◆ ClauseID

◆ Literal

◆ MatchSwitch

◆ Variable

◆ VarMapLattice

Enumeration Type Documentation

◆ LatticeJoinEffect

◆ SkipPast

Function Documentation

◆ blockIndexInPredecessor()

◆ buildBooleanFormula()

◆ buildStmtToBasicBlockMap()

◆ computeBlockInputState()

◆ DebugString()

◆ equivalentValues()

◆ evaluateBooleanEquality()

◆ getAccessibleObjectFields()

◆ getFieldsFromClassHierarchy()

◆ ignoreCFGOmittedNodes() [1/2]

◆ ignoreCFGOmittedNodes() [2/2]

◆ initGlobalVar() [1/2]

◆ initGlobalVar() [2/2]

◆ initGlobalVars()

◆ intersectDenseMaps()

◆ isCheckLikeMethod()

◆ makeCanonicalBoolValuePair()

◆ mergeDistinctValues()

◆ negLit()

◆ notLit()

◆ operator<<() [1/2]

◆ operator<<() [2/2]

◆ posLit()

◆ runDataflowAnalysis()

◆ runTypeErasedDataflowAnalysis()

◆ transfer()

◆ transferBlock()

◆ transferCFGInitializer()

◆ transferCFGStmt()

◆ var()

Variable Documentation

◆ MaxCompositeValueDepth

◆ MaxCompositeValueSize

◆ NullClause

◆ NullLit

◆ NullVar