clang: clang::sema::LambdaScopeInfo Class Reference (original) (raw)

#include "[clang/Sema/ScopeInfo.h](ScopeInfo%5F8h%5Fsource.html)"

Public Member Functions
	LambdaScopeInfo (DiagnosticsEngine &Diag)
void	finishedExplicitCaptures ()
	Note when all explicit captures have been added.
bool	isGenericLambda () const
	Is this scope known to be for a generic lambda? (This will be false until we parse a template parameter list or the first 'auto'-typed parameter).
void	addPotentialCapture (Expr *VarExpr)
	Add a variable that might potentially be captured by the lambda and therefore the enclosing lambdas.
void	addPotentialThisCapture (SourceLocation Loc)
bool	hasPotentialThisCapture () const
void	markVariableExprAsNonODRUsed (Expr *CapturingVarExpr)
	Mark a variable's reference in a lambda as non-odr using.
bool	isVariableExprMarkedAsNonODRUsed (Expr *CapturingVarExpr) const
void	removePotentialCapture (Expr *E)
void	clearPotentialCaptures ()
unsigned	getNumPotentialVariableCaptures () const
bool	hasPotentialCaptures () const
void	visitPotentialCaptures (llvm::function_ref< void(ValueDecl *, Expr *)> Callback) const
bool	lambdaCaptureShouldBeConst () const
Public Member Functions inherited from clang::sema::CapturingScopeInfo
	CapturingScopeInfo (DiagnosticsEngine &Diag, ImplicitCaptureStyle Style)
void	addCapture (ValueDecl *Var, bool isBlock, bool isByref, bool isNested, SourceLocation Loc, SourceLocation EllipsisLoc, QualType CaptureType, bool Invalid)
void	addVLATypeCapture (SourceLocation Loc, const VariableArrayType *VLAType, QualType CaptureType)
void	addThisCapture (bool isNested, SourceLocation Loc, QualType CaptureType, bool ByCopy)
bool	isCXXThisCaptured () const
	Determine whether the C++ 'this' is captured.
Capture &	getCXXThisCapture ()
	Retrieve the capture of C++ 'this', if it has been captured.
bool	isCaptured (ValueDecl *Var) const
	Determine whether the given variable has been captured.
bool	isVLATypeCaptured (const VariableArrayType *VAT) const
	Determine whether the given variable-array type has been captured.
Capture &	getCapture (ValueDecl *Var)
	Retrieve the capture of the given variable, if it has been captured already.
const Capture &	getCapture (ValueDecl *Var) const
Public Member Functions inherited from clang::sema::FunctionScopeInfo
	FunctionScopeInfo (DiagnosticsEngine &Diag)
virtual	~FunctionScopeInfo ()
bool	hasUnrecoverableErrorOccurred () const
	Determine whether an unrecoverable error has occurred within this function.
template
void	recordUseOfWeak (const ExprT *E, bool IsRead=true)
	Record that a weak object was accessed.
void	recordUseOfWeak (const ObjCMessageExpr *Msg, const ObjCPropertyDecl *Prop)
void	markSafeWeakUse (const Expr *E)
	Record that a given expression is a "safe" access of a weak object (e.g.
const WeakObjectUseMap &	getWeakObjectUses () const
void	setHasBranchIntoScope ()
void	setHasBranchProtectedScope ()
void	setHasIndirectGoto ()
void	setHasMustTail ()
void	setHasDroppedStmt ()
void	setHasOMPDeclareReductionCombiner ()
void	setHasFallthroughStmt ()
void	setUsesFPIntrin ()
void	setHasCXXTry (SourceLocation TryLoc)
void	setHasObjCTry (SourceLocation TryLoc)
void	setHasSEHTry (SourceLocation TryLoc)
void	setHasVLA (SourceLocation VLALoc)
bool	NeedsScopeChecking () const
void	addBlock (const BlockDecl *BD)
void	addByrefBlockVar (VarDecl *VD)
bool	isCoroutine () const
void	setFirstCoroutineStmt (SourceLocation Loc, StringRef Keyword)
StringRef	getFirstCoroutineStmtKeyword () const
void	setNeedsCoroutineSuspends (bool value=true)
bool	hasInvalidCoroutineSuspends () const
void	setCoroutineSuspends (Stmt *Initial, Stmt *Final)
void	Clear ()
	Clear out the information in this function scope, making it suitable for reuse.
bool	isPlainFunction () const

Static Public Member Functions
static bool	classof (const FunctionScopeInfo *FSI)
Static Public Member Functions inherited from clang::sema::CapturingScopeInfo
static bool	classof (const FunctionScopeInfo *FSI)

Public Attributes
CXXRecordDecl *	Lambda = nullptr
	The class that describes the lambda.
CXXMethodDecl *	CallOperator = nullptr
	The lambda's compiler-generated operator().
bool	AfterParameterList = true
	Indicate that we parsed the parameter list at which point the mutability of the lambda is known.
ParmVarDecl *	ExplicitObjectParameter = nullptr
SourceRange	IntroducerRange
	Source range covering the lambda introducer [...].
SourceLocation	CaptureDefaultLoc
	Source location of the '&' or '=' specifying the default capture type, if any.
unsigned	NumExplicitCaptures = 0
	The number of captures in the Captures list that are explicit captures.
bool	Mutable = true
	Whether this is a mutable lambda.
bool	ExplicitParams = false
	Whether the (empty) parameter list is explicit.
CleanupInfo	Cleanup
	Whether any of the capture expressions requires cleanups.
SourceRange	ExplicitTemplateParamsRange
	Source range covering the explicit template parameter list (if it exists).
ExprResult	RequiresClause
	The requires-clause immediately following the explicit template parameter list, if any.
TemplateParameterList *	GLTemplateParameterList = nullptr
	If this is a generic lambda, and the template parameter list has been created (from the TemplateParams) then store a reference to it (cache it to avoid reconstructing it).
llvm::SmallVector< Expr *, 4 >	PotentiallyCapturingExprs
	Contains all variable-referring-expressions (i.e.
llvm::SmallSet< Expr *, 8 >	NonODRUsedCapturingExprs
	Contains all variable-referring-expressions that refer to local variables that are usable as constant expressions and do not involve an odr-use (they may still need to be captured if the enclosing full-expression is instantiation dependent).
llvm::DenseMap< unsigned, SourceRange >	ExplicitCaptureRanges
	A map of explicit capture indices to their introducer source ranges.
llvm::SmallVector< ShadowedOuterDecl, 4 >	ShadowingDecls
SourceLocation	PotentialThisCaptureLocation
Public Attributes inherited from clang::sema::CapturingScopeInfo
ImplicitCaptureStyle	ImpCaptureStyle
llvm::DenseMap< ValueDecl *, unsigned >	CaptureMap
	CaptureMap - A map of captured variables to (index+1) into Captures.
unsigned	CXXThisCaptureIndex = 0
	CXXThisCaptureIndex - The (index+1) of the capture of 'this'; zero if 'this' is not captured.
SmallVector< Capture, 4 >	Captures
	Captures - The captures.
bool	HasImplicitReturnType = false
bool	ContainsUnexpandedParameterPack = false
	Whether this contains an unexpanded parameter pack.
QualType	ReturnType
	ReturnType - The target type of return statements in this context, or null if unknown.
SmallVector< NamedDecl *, 4 >	LocalPacks
	Packs introduced by this, if any.
Public Attributes inherited from clang::sema::FunctionScopeInfo
ScopeKind	Kind: 3
	What kind of scope we are describing.
bool	HasBranchProtectedScope: 1
	Whether this function contains a VLA, @try, try, C++ initializer, or anything else that can't be jumped past.
bool	HasBranchIntoScope: 1
	Whether this function contains any switches or direct gotos.
bool	HasIndirectGoto: 1
	Whether this function contains any indirect gotos.
bool	HasMustTail: 1
	Whether this function contains any statement marked with [[clang::musttail]].
bool	HasDroppedStmt: 1
	Whether a statement was dropped because it was invalid.
bool	HasOMPDeclareReductionCombiner: 1
	True if current scope is for OpenMP declare reduction combiner.
bool	HasFallthroughStmt: 1
	Whether there is a fallthrough statement in this function.
bool	UsesFPIntrin: 1
	Whether this function uses constrained floating point intrinsics.
bool	HasPotentialAvailabilityViolations: 1
	Whether we make reference to a declaration that could be unavailable.
bool	ObjCShouldCallSuper: 1
	A flag that is set when parsing a method that must call super's implementation, such as -dealloc, -finalize, or any method marked with __attribute__((objc_requires_super)).
bool	ObjCIsDesignatedInit: 1
	True when this is a method marked as a designated initializer.
bool	ObjCWarnForNoDesignatedInitChain: 1
	This starts true for a method marked as designated initializer and will be set to false if there is an invocation to a designated initializer of the super class.
bool	ObjCIsSecondaryInit: 1
	True when this is an initializer method not marked as a designated initializer within a class that has at least one initializer marked as a designated initializer.
bool	ObjCWarnForNoInitDelegation: 1
	This starts true for a secondary initializer method and will be set to false if there is an invocation of an initializer on 'self'.
bool	NeedsCoroutineSuspends: 1
	True only when this function has not already built, or attempted to build, the initial and final coroutine suspend points.
unsigned char	FirstCoroutineStmtKind: 2
	An enumeration representing the kind of the first coroutine statement in the function.
bool	FoundImmediateEscalatingExpression: 1
	Whether we found an immediate-escalating expression.
SourceLocation	FirstCoroutineStmtLoc
	First coroutine statement in the current function.
SourceLocation	FirstReturnLoc
	First 'return' statement in the current function.
SourceLocation	FirstCXXOrObjCTryLoc
	First C++ 'try' or ObjC @try statement in the current function.
enum clang::sema::FunctionScopeInfo:: { ... }	FirstTryType = Unknown
SourceLocation	FirstSEHTryLoc
	First SEH '__try' statement in the current function.
SourceLocation	FirstVLALoc
	First use of a VLA within the current function.
SmallVector< SwitchInfo, 8 >	SwitchStack
	SwitchStack - This is the current set of active switch statements in the block.
SmallVector< ReturnStmt *, 4 >	Returns
	The list of return statements that occur within the function or block, if there is any chance of applying the named return value optimization, or if we need to infer a return type.
VarDecl *	CoroutinePromise = nullptr
	The promise object for this coroutine, if any.
llvm::SmallMapVector< ParmVarDecl *, Stmt *, 4 >	CoroutineParameterMoves
	A mapping between the coroutine function parameters that were moved to the coroutine frame, and their move statements.
std::pair< Stmt *, Stmt * >	CoroutineSuspends
	The initial and final coroutine suspend points.
SmallVector< CompoundScopeInfo, 4 >	CompoundScopes
	The stack of currently active compound statement scopes in the function.
llvm::SmallPtrSet< const BlockDecl *, 1 >	Blocks
	The set of blocks that are introduced in this function.
llvm::TinyPtrVector< VarDecl * >	ByrefBlockVars
	The set of __block variables that are introduced in this function.
SmallVector< PossiblyUnreachableDiag, 4 >	PossiblyUnreachableDiags
	A list of PartialDiagnostics created but delayed within the current function scope.
llvm::SmallPtrSet< const ParmVarDecl *, 8 >	ModifiedNonNullParams
	A list of parameters which have the nonnull attribute and are modified in the function.
llvm::SmallVector< AddrLabelExpr *, 4 >	AddrLabels
	The set of GNU address of label extension "&&label".
Public Attributes inherited from clang::InventedTemplateParameterInfo
unsigned	NumExplicitTemplateParams = 0
	The number of parameters in the template parameter list that were explicitly specified by the user, as opposed to being invented by use of an auto parameter.
unsigned	AutoTemplateParameterDepth = 0
	If this is a generic lambda or abbreviated function template, use this as the depth of each 'auto' parameter, during initial AST construction.
SmallVector< NamedDecl *, 4 >	TemplateParams
	Store the list of the template parameters for a generic lambda or an abbreviated function template.

Additional Inherited Members
Public Types inherited from clang::sema::CapturingScopeInfo
enum	ImplicitCaptureStyle { ImpCap_None, ImpCap_LambdaByval, ImpCap_LambdaByref, ImpCap_Block, ImpCap_CapturedRegion }
Public Types inherited from clang::sema::FunctionScopeInfo
enum	{ TryLocIsCXX, TryLocIsObjC, Unknown }
using	SwitchInfo = llvm::PointerIntPair< SwitchStmt *, 1, bool >
	A SwitchStmt, along with a flag indicating if its list of case statements is incomplete (because we dropped an invalid one while parsing).
using	WeakUseVector = SmallVector< WeakUseTy, 4 >
	Used to collect uses of a particular weak object in a function body.
using	WeakObjectUseMap = llvm::SmallDenseMap< WeakObjectProfileTy, WeakUseVector, 8, WeakObjectProfileTy::DenseMapInfo >
	Used to collect all uses of weak objects in a function body.
Protected Types inherited from clang::sema::FunctionScopeInfo
enum	ScopeKind { SK_Function, SK_Block, SK_Lambda, SK_CapturedRegion }
Protected Member Functions inherited from clang::sema::CapturingScopeInfo
	CapturingScopeInfo (const CapturingScopeInfo &)=default
Protected Member Functions inherited from clang::sema::FunctionScopeInfo
	FunctionScopeInfo (const FunctionScopeInfo &)=default

Definition at line 867 of file ScopeInfo.h.

◆ addPotentialCapture()

Add a variable that might potentially be captured by the lambda and therefore the enclosing lambdas.

This is also used by enclosing lambda's to speculatively capture variables that nested lambda's - depending on their enclosing specialization - might need to capture. Consider: void f(int, int); <– don't capture void f(const int&, double); <– capture void foo() { const int x = 10; auto L = [=](auto a) { // capture 'x' return [=](auto b) { f(x, a); // we may or may not need to capture 'x' }; }; }

Definition at line 989 of file ScopeInfo.h.

References PotentiallyCapturingExprs.

Referenced by DoMarkPotentialCapture().

◆ addPotentialThisCapture()

◆ classof()

◆ clearPotentialCaptures()

◆ finishedExplicitCaptures()

◆ getNumPotentialVariableCaptures()

◆ hasPotentialCaptures()

◆ hasPotentialThisCapture()

◆ isGenericLambda()

◆ isVariableExprMarkedAsNonODRUsed()

◆ lambdaCaptureShouldBeConst()

◆ markVariableExprAsNonODRUsed()

Mark a variable's reference in a lambda as non-odr using.

For generic lambdas, if a variable is named in a potentially evaluated expression, where the enclosing full expression is dependent then we must capture the variable (given a default capture). This is accomplished by recording all references to variables (DeclRefExprs or MemberExprs) within said nested lambda in its array of PotentialCaptures. All such variables have to be captured by that lambda, except for as described below. If that variable is usable as a constant expression and is named in a manner that does not involve its odr-use (e.g. undergoes lvalue-to-rvalue conversion, or discarded) record that it is so. Upon the act of analyzing the enclosing full expression (ActOnFinishFullExpr) if we can determine that the full expression is not instantiation- dependent, then we can entirely avoid its capture.

const int n = 0; [&] (auto x) { (void)+n + x; }; Interestingly, this strategy would involve a capture of n, even though it's obviously not odr-used here, because the full-expression is instantiation-dependent. It could be useful to avoid capturing such variables, even when they are referred to in an instantiation-dependent expression, if we can unambiguously determine that they shall never be odr-used. This would involve removal of the variable-referring-expression from the array of PotentialCaptures during the lvalue-to-rvalue conversions. But per the working draft N3797, (post-chicago 2013) we must capture such variables. Before anyone is tempted to implement a strategy for not-capturing 'n', consider the insightful warning in: /cfe-commits/Week-of-Mon-20131104/092596.html "The problem is that the set of captures for a lambda is part of the ABI (since lambda layout can be made visible through inline functions and the like), and there are no guarantees as to which cases we'll manage to build an lvalue-to-rvalue conversion in, when parsing a template – some seemingly harmless change elsewhere in Sema could cause us to start or stop building such a node. So we need a rule that anyone can implement and get exactly the same result".

Definition at line 1042 of file ScopeInfo.h.

References NonODRUsedCapturingExprs.

◆ removePotentialCapture()

◆ visitPotentialCaptures()

◆ AfterParameterList

bool clang::sema::LambdaScopeInfo::AfterParameterList = true

◆ CallOperator

CXXMethodDecl* clang::sema::LambdaScopeInfo::CallOperator = nullptr

The lambda's compiler-generated operator().

Definition at line 874 of file ScopeInfo.h.

Referenced by clang::Sema::ActOnCapScopeReturnStmt(), clang::Sema::ActOnLambdaClosureParameters(), clang::Sema::ActOnLambdaClosureQualifiers(), clang::Sema::ActOnLambdaExpr(), clang::Sema::ActOnLambdaExpressionAfterIntroducer(), clang::Sema::ActOnStartOfLambdaDefinition(), adjustCVQualifiersForCXXThisWithinLambda(), clang::Sema::BuildLambdaExpr(), clang::Sema::buildLambdaScope(), clang::Sema::CheckCXXThisCapture(), CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(), DoMarkPotentialCapture(), clang::TreeTransform< Derived >::RebuildLambdaExpr(), clang::Sema::RebuildLambdaScopeInfo(), and clang::Sema::tryCaptureVariable().

◆ CaptureDefaultLoc

◆ Cleanup

◆ ExplicitCaptureRanges

◆ ExplicitObjectParameter

ParmVarDecl* clang::sema::LambdaScopeInfo::ExplicitObjectParameter = nullptr

◆ ExplicitParams

bool clang::sema::LambdaScopeInfo::ExplicitParams = false

◆ ExplicitTemplateParamsRange

SourceRange clang::sema::LambdaScopeInfo::ExplicitTemplateParamsRange

◆ GLTemplateParameterList

◆ IntroducerRange

SourceRange clang::sema::LambdaScopeInfo::IntroducerRange

◆ Lambda

The class that describes the lambda.

Definition at line 871 of file ScopeInfo.h.

Referenced by clang::Sema::ActOnLambdaClosureParameters(), clang::Sema::ActOnLambdaClosureQualifiers(), clang::Sema::ActOnLambdaError(), clang::Sema::ActOnLambdaExpressionAfterIntroducer(), clang::Sema::ActOnStartOfLambdaDefinition(), adjustCVQualifiersForCXXThisWithinLambda(), clang::Sema::BuildLambdaExpr(), clang::Sema::buildLambdaScope(), clang::Sema::CompleteLambdaCallOperator(), clang::TreeTransform< Derived >::ComputeLambdaDependency(), clang::Sema::RebuildLambdaScopeInfo(), and clang::Sema::tryCaptureVariable().

◆ Mutable

bool clang::sema::LambdaScopeInfo::Mutable = true

◆ NonODRUsedCapturingExprs

llvm::SmallSet<Expr *, 8> clang::sema::LambdaScopeInfo::NonODRUsedCapturingExprs

◆ NumExplicitCaptures

unsigned clang::sema::LambdaScopeInfo::NumExplicitCaptures = 0

◆ PotentiallyCapturingExprs

Contains all variable-referring-expressions (i.e.

DeclRefExprs or MemberExprs) that refer to local variables in a generic lambda or a lambda in a potentially-evaluated-if-used context.

Potentially capturable variables of a nested lambda that might need to be captured by the lambda are housed here. This is specifically useful for generic lambdas or lambdas within a potentially evaluated-if-used context. If an enclosing variable is named in an expression of a lambda nested within a generic lambda, we don't always know whether the variable will truly be odr-used (i.e. need to be captured) by that nested lambda, until its instantiation. But we still need to capture it in the enclosing lambda if all intervening lambdas can capture the variable.

Definition at line 930 of file ScopeInfo.h.

Referenced by addPotentialCapture(), clearPotentialCaptures(), getNumPotentialVariableCaptures(), and removePotentialCapture().

◆ PotentialThisCaptureLocation

SourceLocation clang::sema::LambdaScopeInfo::PotentialThisCaptureLocation

◆ RequiresClause

ExprResult clang::sema::LambdaScopeInfo::RequiresClause

◆ ShadowingDecls

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

• include/clang/Sema/ScopeInfo.h
• lib/Sema/ScopeInfo.cpp