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

#include "clang/Analysis/FlowSensitive/DataflowEnvironment.h"

Classes
class	ValueModel
	Supplements `Environment` with non-standard comparison and join operations. More...

Public Member Functions
	Environment (DataflowAnalysisContext &DACtx)
	Creates an environment that uses `DACtx` to store objects that encompass the state of a program.

	Environment (const Environment &Other)

Environment &	operator= (const Environment &Other)

	Environment (Environment &&Other)=default

Environment &	operator= (Environment &&Other)=default

	Environment (DataflowAnalysisContext &DACtx, const DeclContext &DeclCtx)
	Creates an environment that uses `DACtx` to store objects that encompass the state of a program.

Environment	pushCall (const CallExpr *Call) const
	Creates and returns an environment to use for an inline analysis of the callee.

Environment	pushCall (const CXXConstructExpr *Call) const

void	popCall (const CallExpr *Call, const Environment &CalleeEnv)
	Moves gathered information back into `this` from a `CalleeEnv` created via `pushCall`.

void	popCall (const CXXConstructExpr *Call, const Environment &CalleeEnv)

bool	equivalentTo (const Environment &Other, Environment::ValueModel &Model) const
	Returns true if and only if the environment is equivalent to `Other`, i.e the two environments:

LatticeJoinEffect	join (const Environment &Other, Environment::ValueModel &Model)
	Joins the environment with `Other` by taking the intersection of storage locations and values that are stored in them.

LatticeJoinEffect	widen (const Environment &PrevEnv, Environment::ValueModel &Model)
	Widens the environment point-wise, using `PrevEnv` as needed to inform the approximation.

StorageLocation &	createStorageLocation (QualType Type)
	Creates a storage location appropriate for `Type`.

StorageLocation &	createStorageLocation (const VarDecl &D)
	Creates a storage location for `D`.

StorageLocation &	createStorageLocation (const Expr &E)
	Creates a storage location for `E`.

void	setStorageLocation (const ValueDecl &D, StorageLocation &Loc)
	Assigns `Loc` as the storage location of `D` in the environment.

StorageLocation *	getStorageLocation (const ValueDecl &D) const
	Returns the storage location assigned to `D` in the environment, or null if `D` isn't assigned a storage location in the environment.

void	setStorageLocation (const Expr &E, StorageLocation &Loc)
	Assigns `Loc` as the storage location of `E` in the environment.

void	setStorageLocationStrict (const Expr &E, StorageLocation &Loc)
	Assigns `Loc` as the storage location of the glvalue `E` in the environment.

StorageLocation *	getStorageLocation (const Expr &E, SkipPast SP) const
	Returns the storage location assigned to `E` in the environment, applying the `SP` policy for skipping past indirections, or null if `E` isn't assigned a storage location in the environment.

StorageLocation *	getStorageLocationStrict (const Expr &E) const
	Returns the storage location assigned to the glvalue `E` in the environment, or null if `E` isn't assigned a storage location in the environment.

StorageLocation *	getThisPointeeStorageLocation () const
	Returns the storage location assigned to the `this` pointee in the environment or null if the `this` pointee has no assigned storage location in the environment.

Value *	getReturnValue () const
	Returns the return value of the current function.

StorageLocation *	getReturnStorageLocation () const
	Returns the storage location for the reference returned by the current function.

void	setReturnValue (Value *Val)
	Sets the return value of the current function.

void	setReturnStorageLocation (StorageLocation *Loc)
	Sets the storage location for the reference returned by the current function.

PointerValue &	getOrCreateNullPointerValue (QualType PointeeType)
	Returns a pointer value that represents a null pointer.

Value *	createValue (QualType Type)
	Creates a value appropriate for `Type`, if `Type` is supported, otherwise return null.

void	setValue (const StorageLocation &Loc, Value &Val)
	Assigns `Val` as the value of `Loc` in the environment.

void	setValueStrict (const Expr &E, Value &Val)
	Assigns `Val` as the value of the prvalue `E` in the environment.

Value *	getValue (const StorageLocation &Loc) const
	Returns the value assigned to `Loc` in the environment or null if `Loc` isn't assigned a value in the environment.

Value *	getValue (const ValueDecl &D) const
	Equivalent to `getValue(getStorageLocation(D, SP), SkipPast::None)` if `D` is assigned a storage location in the environment, otherwise returns null.

Value *	getValue (const Expr &E, SkipPast SP) const
	Equivalent to `getValue(getStorageLocation(E, SP), SkipPast::None)` if `E` is assigned a storage location in the environment, otherwise returns null.

Value *	getValueStrict (const Expr &E) const
	Returns the `Value` assigned to the prvalue `E` in the environment, or null if `E` isn't assigned a value in the environment.

template<typename T , typename... Args>
std::enable_if_t< std::is_base_of< Value, T >::value, T & >	create (Args &&...args)
	Creates a `T` (some subclass of `Value`), forwarding `args` to the constructor, and returns a reference to it.

AtomicBoolValue &	getBoolLiteralValue (bool Value) const
	Returns a symbolic boolean value that models a boolean literal equal to `Value`

BoolValue &	makeAtomicBoolValue () const
	Returns an atomic boolean value.

BoolValue &	makeTopBoolValue () const
	Returns a unique instance of boolean Top.

BoolValue &	makeAnd (BoolValue &LHS, BoolValue &RHS) const
	Returns a boolean value that represents the conjunction of `LHS` and `RHS`.

BoolValue &	makeOr (BoolValue &LHS, BoolValue &RHS) const
	Returns a boolean value that represents the disjunction of `LHS` and `RHS`.

BoolValue &	makeNot (BoolValue &Val) const
	Returns a boolean value that represents the negation of `Val`.

BoolValue &	makeImplication (BoolValue &LHS, BoolValue &RHS) const
	Returns a boolean value represents `LHS` => `RHS`.

BoolValue &	makeIff (BoolValue &LHS, BoolValue &RHS) const
	Returns a boolean value represents `LHS` <=> `RHS`.

AtomicBoolValue &	getFlowConditionToken () const
	Returns the token that identifies the flow condition of the environment.

void	addToFlowCondition (BoolValue &Val)
	Adds `Val` to the set of clauses that constitute the flow condition.

bool	flowConditionImplies (BoolValue &Val) const
	Returns true if and only if the clauses that constitute the flow condition imply that `Val` is true.

const DeclContext *	getDeclCtx () const
	Returns the `DeclContext` of the block being analysed, if any.

const FunctionDecl *	getCurrentFunc () const
	Returns the function currently being analyzed, or null if the code being analyzed isn't part of a function.

bool	canDescend (unsigned MaxDepth, const DeclContext *Callee) const
	Returns whether this `Environment` can be extended to analyze the given `Callee` (i.e.

DataflowAnalysisContext &	getDataflowAnalysisContext () const
	Returns the `DataflowAnalysisContext` used by the environment.

LLVM_DUMP_METHOD void	dump () const

LLVM_DUMP_METHOD void	dump (raw_ostream &OS) const

Detailed Description

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

WARNING: Symbolic values that are created by the environment for static local and global variables are not currently invalidated on function calls. This is unsound and should be taken into account when designing dataflow analyses.

Definition at line 64 of file DataflowEnvironment.h.

Constructor & Destructor Documentation

◆ Environment() [1/4]

clang::dataflow::Environment::Environment ( DataflowAnalysisContext & DACtx )

explicit

Creates an environment that uses DACtx to store objects that encompass the state of a program.

Definition at line 264 of file DataflowEnvironment.cpp.

◆ Environment() [2/4]

clang::dataflow::Environment::Environment ( const Environment & Other )

Definition at line 268 of file DataflowEnvironment.cpp.

◆ Environment() [3/4]

clang::dataflow::Environment::Environment ( Environment && Other )

default

◆ Environment() [4/4]

clang::dataflow::Environment::Environment	(	DataflowAnalysisContext &	DACtx,
		const DeclContext &	DeclCtx
	)

Creates an environment that uses DACtx to store objects that encompass the state of a program.

If DeclCtx is a function, initializes the environment with symbolic representations of the function parameters.

If DeclCtx is a non-static member function, initializes the environment with a symbolic representation of the this pointee.

Definition at line 283 of file DataflowEnvironment.cpp.

References createStorageLocation(), createValue(), clang::FunctionDecl::getBody(), clang::FunctionDecl::parameters(), Parent, setStorageLocation(), and setValue().

Member Function Documentation

◆ addToFlowCondition()

void clang::dataflow::Environment::addToFlowCondition ( BoolValue & Val )

Adds Val to the set of clauses that constitute the flow condition.

Definition at line 888 of file DataflowEnvironment.cpp.

References clang::dataflow::DataflowAnalysisContext::addFlowConditionConstraint().

Referenced by clang::dataflow::UncheckedOptionalAccessModel::merge(), and clang::dataflow::mergeDistinctValues().

◆ canDescend()

bool clang::dataflow::Environment::canDescend	(	unsigned	MaxDepth,
		const DeclContext *	Callee
	)		const

Returns whether this Environment can be extended to analyze the given Callee (i.e.

if pushCall can be used), with recursion disallowed and a given MaxDepth.

Definition at line 324 of file DataflowEnvironment.cpp.

◆ create()

template<typename T , typename... Args>

std::enable_if_t< std::is_base_of< Value, T >::value, T & > clang::dataflow::Environment::create ( Args &&... args )

inline

Creates a T (some subclass of Value), forwarding args to the constructor, and returns a reference to it.

The analysis context takes ownership of the created object. The object will be destroyed when the analysis context is destroyed.

Definition at line 447 of file DataflowEnvironment.h.

References clang::dataflow::DataflowAnalysisContext::arena(), and clang::dataflow::Arena::create().

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

◆ createStorageLocation() [1/3]

StorageLocation & clang::dataflow::Environment::createStorageLocation ( const Expr & E )

Creates a storage location for E.

Does not assign the returned storage location to E in the environment. Does not assign a value to the returned storage location in the environment.

Definition at line 647 of file DataflowEnvironment.cpp.

References clang::dataflow::DataflowAnalysisContext::getStableStorageLocation().

◆ createStorageLocation() [2/3]

StorageLocation & clang::dataflow::Environment::createStorageLocation ( const VarDecl & D )

Creates a storage location for D.

Does not assign the returned storage location to D in the environment. Does not assign a value to the returned storage location in the environment.

Definition at line 640 of file DataflowEnvironment.cpp.

References clang::dataflow::DataflowAnalysisContext::getStableStorageLocation().

◆ createStorageLocation() [3/3]

StorageLocation & clang::dataflow::Environment::createStorageLocation ( QualType Type )

Creates a storage location appropriate for Type.

Does not assign a value to the returned storage location in the environment.

Requirements:

Type must not be null.

Definition at line 636 of file DataflowEnvironment.cpp.

References clang::dataflow::DataflowAnalysisContext::createStorageLocation().

Referenced by Environment(), and setValueStrict().

◆ createValue()

Value * clang::dataflow::Environment::createValue ( QualType Type )

Creates a value appropriate for Type, if Type is supported, otherwise return null.

If Type is a pointer or reference type, creates all the necessary storage locations and values for indirections until it finds a non-pointer/non-reference type.

Requirements:

Type must not be null.

Definition at line 791 of file DataflowEnvironment.cpp.

References clang::dataflow::MaxCompositeValueSize, and Visited.

Referenced by Environment(), and clang::dataflow::mergeDistinctValues().

◆ dump() [1/2]

void clang::dataflow::Environment::dump ( ) const

Definition at line 916 of file DataflowEnvironment.cpp.

References dump().

Referenced by dump(), and clang::dataflow::runTypeErasedDataflowAnalysis().

◆ dump() [2/2]

void clang::dataflow::Environment::dump ( raw_ostream & OS ) const

Definition at line 896 of file DataflowEnvironment.cpp.

References clang::dataflow::DataflowAnalysisContext::dumpFlowCondition(), and V.

◆ equivalentTo()

bool clang::dataflow::Environment::equivalentTo	(	const Environment &	Other,
		Environment::ValueModel &	Model
	)		const

Returns true if and only if the environment is equivalent to Other, i.e the two environments:

have the same mappings from declarations to storage locations,
have the same mappings from expressions to storage locations,
have the same or equivalent (according to Model) values assigned to the same storage locations.

Requirements:

Other and this must use the same DataflowAnalysisContext.

Definition at line 435 of file DataflowEnvironment.cpp.

References clang::dataflow::areEquivalentValues(), clang::dataflow::compareDistinctValues(), and clang::dataflow::StorageLocation::getType().

◆ flowConditionImplies()

bool clang::dataflow::Environment::flowConditionImplies ( BoolValue & Val ) const

Returns true if and only if the clauses that constitute the flow condition imply that Val is true.

Definition at line 892 of file DataflowEnvironment.cpp.

References clang::dataflow::DataflowAnalysisContext::flowConditionImplies().

◆ getBoolLiteralValue()

AtomicBoolValue & clang::dataflow::Environment::getBoolLiteralValue ( bool Value ) const

inline

Returns a symbolic boolean value that models a boolean literal equal to Value

Definition at line 453 of file DataflowEnvironment.h.

References clang::dataflow::DataflowAnalysisContext::arena(), and clang::dataflow::Arena::makeLiteral().

◆ getCurrentFunc()

const FunctionDecl * clang::dataflow::Environment::getCurrentFunc ( ) const

inline

Returns the function currently being analyzed, or null if the code being analyzed isn't part of a function.

Definition at line 521 of file DataflowEnvironment.h.

References getDeclCtx().

Referenced by getReturnStorageLocation(), getReturnValue(), setReturnStorageLocation(), and setReturnValue().

◆ getDataflowAnalysisContext()

DataflowAnalysisContext & clang::dataflow::Environment::getDataflowAnalysisContext ( ) const

inline

Returns the DataflowAnalysisContext used by the environment.

Definition at line 531 of file DataflowEnvironment.h.

◆ getDeclCtx()

const DeclContext * clang::dataflow::Environment::getDeclCtx ( ) const

inline

Returns the DeclContext of the block being analysed, if any.

Otherwise, returns null.

Definition at line 517 of file DataflowEnvironment.h.

Referenced by getCurrentFunc().

◆ getFlowConditionToken()

AtomicBoolValue & clang::dataflow::Environment::getFlowConditionToken ( ) const

inline

Returns the token that identifies the flow condition of the environment.

Definition at line 506 of file DataflowEnvironment.h.

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

◆ getOrCreateNullPointerValue()

PointerValue & clang::dataflow::Environment::getOrCreateNullPointerValue ( QualType PointeeType )

Returns a pointer value that represents a null pointer.

Calls with PointeeType that are canonically equivalent will return the same result.

Definition at line 714 of file DataflowEnvironment.cpp.

References clang::dataflow::DataflowAnalysisContext::getOrCreateNullPointerValue().

◆ getReturnStorageLocation()

StorageLocation * clang::dataflow::Environment::getReturnStorageLocation ( ) const

inline

Returns the storage location for the reference returned by the current function.

This can be null if function doesn't return a single consistent reference.

Requirements: The current function must have a reference return type.

Definition at line 346 of file DataflowEnvironment.h.

References getCurrentFunc().

◆ getReturnValue()

Value * clang::dataflow::Environment::getReturnValue ( ) const

inline

Returns the return value of the current function.

This can be null if:

The function has a void return type
No return value could be determined for the function, for example because it calls a function without a body.

Requirements: The current function must have a non-reference return type.

Definition at line 334 of file DataflowEnvironment.h.

References getCurrentFunc().

◆ getStorageLocation() [1/2]

StorageLocation * clang::dataflow::Environment::getStorageLocation	(	const Expr &	E,
		SkipPast	SP
	)		const

Returns the storage location assigned to E in the environment, applying the SP policy for skipping past indirections, or null if E isn't assigned a storage location in the environment.

This function is deprecated; prefer getStorageLocationStrict(). For details, see https://discourse.llvm.org/t/70086.

Definition at line 688 of file DataflowEnvironment.cpp.

References clang::dataflow::ignoreCFGOmittedNodes().

◆ getStorageLocation() [2/2]

StorageLocation * clang::dataflow::Environment::getStorageLocation ( const ValueDecl & D ) const

Returns the storage location assigned to D in the environment, or null if D isn't assigned a storage location in the environment.

Note that if D has reference type, the storage location that is returned refers directly to the referenced object, not a ReferenceValue.

Definition at line 660 of file DataflowEnvironment.cpp.

References getValue().

Referenced by clang::dataflow::getBaseObjectLocation(), clang::dataflow::getImplicitObjectLocation(), getStorageLocationStrict(), getValue(), pushCall(), and setValueStrict().

◆ getStorageLocationStrict()

StorageLocation * clang::dataflow::Environment::getStorageLocationStrict ( const Expr & E ) const

Returns the storage location assigned to the glvalue E in the environment, or null if E isn't assigned a storage location in the environment.

If the storage location for E is associated with a ReferenceValue RefVal, returns RefVal.getReferentLoc() instead.

This function is the preferred alternative to getStorageLocation(const Expr &, SkipPast). Once the migration to strict handling of value categories is complete (see https://discourse.llvm.org/t/70086), getStorageLocation() will be removed and this function will be renamed to getStorageLocation().

Requirements: E must be a glvalue or a BuiltinType::BuiltinFn

Definition at line 695 of file DataflowEnvironment.cpp.

References getStorageLocation(), clang::Expr::getType(), getValue(), clang::Expr::isGLValue(), clang::Type::isSpecificBuiltinType(), and clang::dataflow::None.

Referenced by clang::dataflow::builtinTransferInitializer(), clang::dataflow::maybeUnpackLValueExpr(), and clang::dataflow::propagateStorageLocation().

◆ getThisPointeeStorageLocation()

StorageLocation * clang::dataflow::Environment::getThisPointeeStorageLocation ( ) const

Returns the storage location assigned to the this pointee in the environment or null if the this pointee has no assigned storage location in the environment.

Definition at line 710 of file DataflowEnvironment.cpp.

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

◆ getValue() [1/3]

Value * clang::dataflow::Environment::getValue	(	const Expr &	E,
		SkipPast	SP
	)		const

Equivalent to getValue(getStorageLocation(E, SP), SkipPast::None) if E is assigned a storage location in the environment, otherwise returns null.

This function is deprecated; prefer getValueStrict(). For details, see https://discourse.llvm.org/t/70086.

Definition at line 775 of file DataflowEnvironment.cpp.

References getStorageLocation(), and getValue().

◆ getValue() [2/3]

Value * clang::dataflow::Environment::getValue ( const StorageLocation & Loc ) const

Returns the value assigned to Loc in the environment or null if Loc isn't assigned a value in the environment.

Definition at line 763 of file DataflowEnvironment.cpp.

Referenced by clang::dataflow::getBaseObjectLocation(), clang::dataflow::getImplicitObjectLocation(), getStorageLocation(), getStorageLocationStrict(), getValue(), getValueStrict(), clang::dataflow::maybeUnpackLValueExpr(), popCall(), and setStorageLocation().

◆ getValue() [3/3]

Value * clang::dataflow::Environment::getValue ( const ValueDecl & D ) const

Equivalent to getValue(getStorageLocation(D, SP), SkipPast::None) if D is assigned a storage location in the environment, otherwise returns null.

Definition at line 768 of file DataflowEnvironment.cpp.

References getStorageLocation(), and getValue().

◆ getValueStrict()

Value * clang::dataflow::Environment::getValueStrict ( const Expr & E ) const

Returns the Value assigned to the prvalue E in the environment, or null if E isn't assigned a value in the environment.

This function is the preferred alternative to getValue(const Expr &, SkipPast). Once the migration to strict handling of value categories is complete (see https://discourse.llvm.org/t/70086), getValue() will be removed and this function will be renamed to getValue().

Requirements:

E must be a prvalue

Definition at line 782 of file DataflowEnvironment.cpp.

References getValue(), clang::Expr::isPRValue(), and clang::dataflow::None.

Referenced by clang::dataflow::builtinTransferInitializer(), clang::dataflow::evaluateBooleanEquality(), and clang::dataflow::propagateValue().

◆ join()

LatticeJoinEffect clang::dataflow::Environment::join	(	const Environment &	Other,
		Environment::ValueModel &	Model
	)

Joins the environment with Other by taking the intersection of storage locations and values that are stored in them.

Distinct values that are assigned to the same storage locations in the environment and Other are merged using Model.

Requirements:

Other and this must use the same DataflowAnalysisContext.

Definition at line 538 of file DataflowEnvironment.cpp.

References clang::dataflow::areEquivalentValues(), clang::dataflow::Changed, clang::dataflow::StorageLocation::getType(), clang::dataflow::intersectDenseMaps(), clang::dataflow::DataflowAnalysisContext::joinFlowConditions(), clang::dataflow::mergeDistinctValues(), and clang::dataflow::Unchanged.

◆ makeAnd()

BoolValue & clang::dataflow::Environment::makeAnd	(	BoolValue &	LHS,
		BoolValue &	RHS
	)		const

inline

Returns a boolean value that represents the conjunction of LHS and RHS.

Subsequent calls with the same arguments, regardless of their order, will return the same result. If the given boolean values represent the same value, the result will be the value itself.

Definition at line 471 of file DataflowEnvironment.h.

References clang::dataflow::DataflowAnalysisContext::arena(), and clang::dataflow::Arena::makeAnd().

Referenced by clang::dataflow::mergeDistinctValues(), and clang::dataflow::unpackValue().

◆ makeAtomicBoolValue()

BoolValue & clang::dataflow::Environment::makeAtomicBoolValue ( ) const

inline

Returns an atomic boolean value.

Definition at line 458 of file DataflowEnvironment.h.

References clang::dataflow::DataflowAnalysisContext::arena(), and clang::dataflow::Arena::create().

Referenced by clang::dataflow::evaluateBooleanEquality(), clang::dataflow::UncheckedOptionalAccessModel::merge(), clang::dataflow::mergeDistinctValues(), and clang::dataflow::unpackValue().

◆ makeIff()

BoolValue & clang::dataflow::Environment::makeIff	(	BoolValue &	LHS,
		BoolValue &	RHS
	)		const

inline

Returns a boolean value represents LHS <=> RHS.

Subsequent calls with the same arguments, regardless of their order, will return the same result. If the given boolean values represent the same value, the result will be a value that represents the true boolean literal.

Definition at line 501 of file DataflowEnvironment.h.

References clang::dataflow::DataflowAnalysisContext::arena(), and clang::dataflow::Arena::makeEquals().

Referenced by clang::dataflow::evaluateBooleanEquality(), clang::dataflow::mergeDistinctValues(), and clang::dataflow::unpackValue().

◆ makeImplication()

BoolValue & clang::dataflow::Environment::makeImplication	(	BoolValue &	LHS,
		BoolValue &	RHS
	)		const

inline

Returns a boolean value represents LHS => RHS.

Subsequent calls with the same arguments, will return the same result. If the given boolean values represent the same value, the result will be a value that represents the true boolean literal.

Definition at line 493 of file DataflowEnvironment.h.

References clang::dataflow::DataflowAnalysisContext::arena(), and clang::dataflow::Arena::makeImplies().

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

◆ makeNot()

BoolValue & clang::dataflow::Environment::makeNot ( BoolValue & Val ) const

inline

Returns a boolean value that represents the negation of Val.

Subsequent calls with the same argument will return the same result.

Definition at line 485 of file DataflowEnvironment.h.

References clang::dataflow::DataflowAnalysisContext::arena(), and clang::dataflow::Arena::makeNot().

Referenced by clang::dataflow::UncheckedOptionalAccessModel::merge(), and clang::dataflow::unpackValue().

◆ makeOr()

BoolValue & clang::dataflow::Environment::makeOr	(	BoolValue &	LHS,
		BoolValue &	RHS
	)		const

inline

Returns a boolean value that represents the disjunction of LHS and RHS.

Subsequent calls with the same arguments, regardless of their order, will return the same result. If the given boolean values represent the same value, the result will be the value itself.

Definition at line 479 of file DataflowEnvironment.h.

References clang::dataflow::DataflowAnalysisContext::arena(), and clang::dataflow::Arena::makeOr().

Referenced by clang::dataflow::mergeDistinctValues(), and clang::dataflow::unpackValue().

◆ makeTopBoolValue()

BoolValue & clang::dataflow::Environment::makeTopBoolValue ( ) const

inline

Returns a unique instance of boolean Top.

Definition at line 463 of file DataflowEnvironment.h.

References clang::dataflow::DataflowAnalysisContext::arena(), and clang::dataflow::Arena::create().

Referenced by clang::dataflow::UncheckedOptionalAccessModel::widen(), and clang::dataflow::widenDistinctValues().

◆ operator=() [1/2]

Environment & clang::dataflow::Environment::operator= ( const Environment & Other )

Definition at line 277 of file DataflowEnvironment.cpp.

◆ operator=() [2/2]

Environment & clang::dataflow::Environment::operator= ( Environment && Other )

default

◆ popCall() [1/2]

void clang::dataflow::Environment::popCall	(	const CallExpr *	Call,
		const Environment &	CalleeEnv
	)

Moves gathered information back into this from a CalleeEnv created via pushCall.

Definition at line 402 of file DataflowEnvironment.cpp.

References setStorageLocationStrict(), and setValueStrict().

◆ popCall() [2/2]

void clang::dataflow::Environment::popCall	(	const CXXConstructExpr *	Call,
		const Environment &	CalleeEnv
	)

Definition at line 423 of file DataflowEnvironment.cpp.

References getValue(), and setValueStrict().

◆ pushCall() [1/2]

Environment clang::dataflow::Environment::pushCall ( const CallExpr * Call ) const

Creates and returns an environment to use for an inline analysis of the callee.

Uses the storage location from each argument in the Call as the storage location for the corresponding parameter in the callee.

Requirements:

The callee of Call must be a FunctionDecl.

The body of the callee must not reference globals.

The arguments of Call must map 1:1 to the callee's parameters.

Definition at line 329 of file DataflowEnvironment.cpp.

References Env, getStorageLocation(), and clang::dataflow::Reference.

◆ pushCall() [2/2]

Environment clang::dataflow::Environment::pushCall ( const CXXConstructExpr * Call ) const

Definition at line 347 of file DataflowEnvironment.cpp.

References Env.

◆ setReturnStorageLocation()

void clang::dataflow::Environment::setReturnStorageLocation ( StorageLocation * Loc )

inline

Sets the storage location for the reference returned by the current function.

Requirements: The current function must have a reference return type.

Definition at line 367 of file DataflowEnvironment.h.

References getCurrentFunc().

◆ setReturnValue()

void clang::dataflow::Environment::setReturnValue ( Value * Val )

inline

Sets the return value of the current function.

Requirements: The current function must have a non-reference return type.

Definition at line 356 of file DataflowEnvironment.h.

References getCurrentFunc().

◆ setStorageLocation() [1/2]

void clang::dataflow::Environment::setStorageLocation	(	const Expr &	E,
		StorageLocation &	Loc
	)

Assigns Loc as the storage location of E in the environment.

This function is deprecated; prefer setStorageLocationStrict(). For details, see https://discourse.llvm.org/t/70086.

Requirements:

E must not be assigned a storage location in the environment.

Definition at line 672 of file DataflowEnvironment.cpp.

References clang::dataflow::ignoreCFGOmittedNodes().

◆ setStorageLocation() [2/2]

void clang::dataflow::Environment::setStorageLocation	(	const ValueDecl &	D,
		StorageLocation &	Loc
	)

Assigns Loc as the storage location of D in the environment.

Requirements:

D must not already have a storage location in the environment.

If D has reference type, Loc must refer directly to the referenced object (if any), not to a ReferenceValue, and it is not permitted to later change Loc to refer to a ReferenceValue.

Definition at line 654 of file DataflowEnvironment.cpp.

References getValue().

Referenced by Environment(), setStorageLocationStrict(), and setValueStrict().

◆ setStorageLocationStrict()

void clang::dataflow::Environment::setStorageLocationStrict	(	const Expr &	E,
		StorageLocation &	Loc
	)

Assigns Loc as the storage location of the glvalue E in the environment.

This function is the preferred alternative to setStorageLocation(const Expr &, StorageLocation &). Once the migration to strict handling of value categories is complete (see https://discourse.llvm.org/t/70086), setStorageLocation() will be removed and this function will be renamed to setStorageLocation().

Requirements:

E must not be assigned a storage location in the environment. E must be a glvalue or a BuiltinType::BuiltinFn

Definition at line 678 of file DataflowEnvironment.cpp.

References clang::Expr::getType(), clang::Expr::isGLValue(), clang::Type::isSpecificBuiltinType(), and setStorageLocation().

Referenced by popCall(), and clang::dataflow::propagateStorageLocation().

◆ setValue()

void clang::dataflow::Environment::setValue	(	const StorageLocation &	Loc,
		Value &	Val
	)

Assigns Val as the value of Loc in the environment.

Definition at line 718 of file DataflowEnvironment.cpp.

References clang::Type::isRecordType(), clang::Member, clang::dataflow::StructValue::setChild(), and setValue().

Referenced by clang::dataflow::builtinTransferInitializer(), Environment(), clang::dataflow::maybeUnpackLValueExpr(), setValue(), and setValueStrict().

◆ setValueStrict()

void clang::dataflow::Environment::setValueStrict	(	const Expr &	E,
		Value &	Val
	)

Assigns Val as the value of the prvalue E in the environment.

If E is not yet associated with a storage location, associates it with a newly created storage location. In any case, associates the storage location of E with Val.

Once the migration to strict handling of value categories is complete (see https://discourse.llvm.org/t/70086), this function will be renamed to setValue(). At this point, prvalue expressions will be associated directly with Values, and the legacy behavior of associating prvalue expressions with storage locations (as described above) will be eliminated.

Requirements:

E must be a prvalue Val must not be a ReferenceValue

Definition at line 751 of file DataflowEnvironment.cpp.

References createStorageLocation(), getStorageLocation(), clang::Expr::isPRValue(), clang::dataflow::None, setStorageLocation(), and setValue().

Referenced by popCall(), and clang::dataflow::propagateValue().

◆ widen()

LatticeJoinEffect clang::dataflow::Environment::widen	(	const Environment &	PrevEnv,
		Environment::ValueModel &	Model
	)

Widens the environment point-wise, using PrevEnv as needed to inform the approximation.

Requirements:

PrevEnv must be the immediate previous version of the environment. PrevEnv and this must use the same DataflowAnalysisContext.

Definition at line 476 of file DataflowEnvironment.cpp.

References clang::dataflow::areEquivalentValues(), clang::dataflow::Changed, clang::dataflow::StorageLocation::getType(), clang::dataflow::Unchanged, and clang::dataflow::widenDistinctValues().

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

The documentation for this class was generated from the following files:

include/clang/Analysis/FlowSensitive/DataflowEnvironment.h
lib/Analysis/FlowSensitive/DataflowEnvironment.cpp

Classes

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ Environment() [1/4]

◆ Environment() [2/4]

◆ Environment() [3/4]

◆ Environment() [4/4]

Member Function Documentation

◆ addToFlowCondition()

◆ canDescend()

◆ create()

◆ createStorageLocation() [1/3]

◆ createStorageLocation() [2/3]

◆ createStorageLocation() [3/3]

◆ createValue()

◆ dump() [1/2]

◆ dump() [2/2]

◆ equivalentTo()

◆ flowConditionImplies()

◆ getBoolLiteralValue()

◆ getCurrentFunc()

◆ getDataflowAnalysisContext()

◆ getDeclCtx()

◆ getFlowConditionToken()

◆ getOrCreateNullPointerValue()

◆ getReturnStorageLocation()

◆ getReturnValue()

◆ getStorageLocation() [1/2]

◆ getStorageLocation() [2/2]

◆ getStorageLocationStrict()

◆ getThisPointeeStorageLocation()

◆ getValue() [1/3]

◆ getValue() [2/3]

◆ getValue() [3/3]

◆ getValueStrict()

◆ join()

◆ makeAnd()

◆ makeAtomicBoolValue()

◆ makeIff()

◆ makeImplication()

◆ makeNot()

◆ makeOr()

◆ makeTopBoolValue()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ popCall() [1/2]

◆ popCall() [2/2]

◆ pushCall() [1/2]

◆ pushCall() [2/2]

◆ setReturnStorageLocation()

◆ setReturnValue()

◆ setStorageLocation() [1/2]

◆ setStorageLocation() [2/2]

◆ setStorageLocationStrict()

◆ setValue()

◆ setValueStrict()

◆ widen()