clang  6.0.0svn
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clang::ento::CheckerDocumentation Class Reference

This checker documents the callback functions checkers can use to implement the custom handling of the specific events during path exploration as well as reporting bugs. More...

Inheritance diagram for clang::ento::CheckerDocumentation:
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Collaboration diagram for clang::ento::CheckerDocumentation:
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Public Member Functions

void checkPreStmt (const ReturnStmt *DS, CheckerContext &C) const
 Pre-visit the Statement. More...
 
void checkPostStmt (const DeclStmt *DS, CheckerContext &C) const
 Post-visit the Statement. More...
 
void checkPreObjCMessage (const ObjCMethodCall &M, CheckerContext &C) const
 Pre-visit the Objective C message. More...
 
void checkPostObjCMessage (const ObjCMethodCall &M, CheckerContext &C) const
 Post-visit the Objective C message. More...
 
void checkObjCMessageNil (const ObjCMethodCall &M, CheckerContext &C) const
 Visit an Objective-C message whose receiver is nil. More...
 
void checkPreCall (const CallEvent &Call, CheckerContext &C) const
 Pre-visit an abstract "call" event. More...
 
void checkPostCall (const CallEvent &Call, CheckerContext &C) const
 Post-visit an abstract "call" event. More...
 
void checkBranchCondition (const Stmt *Condition, CheckerContext &Ctx) const
 Pre-visit of the condition statement of a branch (such as IfStmt). More...
 
void checkLocation (SVal Loc, bool IsLoad, const Stmt *S, CheckerContext &) const
 Called on a load from and a store to a location. More...
 
void checkBind (SVal Loc, SVal Val, const Stmt *S, CheckerContext &) const
 Called on binding of a value to a location. More...
 
void checkDeadSymbols (SymbolReaper &SR, CheckerContext &C) const
 Called whenever a symbol becomes dead. More...
 
void checkBeginFunction (CheckerContext &Ctx) const
 Called when the analyzer core starts analyzing a function, regardless of whether it is analyzed at the top level or is inlined. More...
 
void checkEndFunction (CheckerContext &Ctx) const
 Called when the analyzer core reaches the end of a function being analyzed regardless of whether it is analyzed at the top level or is inlined. More...
 
void checkEndAnalysis (ExplodedGraph &G, BugReporter &BR, ExprEngine &Eng) const
 Called after all the paths in the ExplodedGraph reach end of path. More...
 
void checkEndOfTranslationUnit (const TranslationUnitDecl *TU, AnalysisManager &Mgr, BugReporter &BR) const
 Called after analysis of a TranslationUnit is complete. More...
 
bool evalCall (const CallExpr *CE, CheckerContext &C) const
 Evaluates function call. More...
 
ProgramStateRef evalAssume (ProgramStateRef State, SVal Cond, bool Assumption) const
 Handles assumptions on symbolic values. More...
 
void checkLiveSymbols (ProgramStateRef State, SymbolReaper &SR) const
 Allows modifying SymbolReaper object. More...
 
ProgramStateRef checkRegionChanges (ProgramStateRef State, const InvalidatedSymbols *Invalidated, ArrayRef< const MemRegion *> ExplicitRegions, ArrayRef< const MemRegion *> Regions, const LocationContext *LCtx, const CallEvent *Call) const
 Called when the contents of one or more regions change. More...
 
ProgramStateRef checkPointerEscape (ProgramStateRef State, const InvalidatedSymbols &Escaped, const CallEvent *Call, PointerEscapeKind Kind) const
 Called when pointers escape. More...
 
ProgramStateRef checkConstPointerEscape (ProgramStateRef State, const InvalidatedSymbols &Escaped, const CallEvent *Call, PointerEscapeKind Kind) const
 Called when const pointers escape. More...
 
void checkEvent (ImplicitNullDerefEvent Event) const
 check::Event<ImplicitNullDerefEvent> More...
 
void checkASTDecl (const FunctionDecl *D, AnalysisManager &Mgr, BugReporter &BR) const
 Check every declaration in the AST. More...
 
- Public Member Functions inherited from clang::ento::CheckerBase
StringRef getTagDescription () const override
 
CheckName getCheckName () const
 
virtual void printState (raw_ostream &Out, ProgramStateRef State, const char *NL, const char *Sep) const
 See CheckerManager::runCheckersForPrintState. More...
 
- Public Member Functions inherited from clang::ProgramPointTag
 ProgramPointTag (void *tagKind=nullptr)
 
virtual ~ProgramPointTag ()
 

Additional Inherited Members

- Static Public Member Functions inherited from clang::ento::Checker< check::PreStmt< ReturnStmt >, check::PostStmt< DeclStmt >, check::PreObjCMessage, check::PostObjCMessage, check::ObjCMessageNil, check::PreCall, check::PostCall, check::BranchCondition, check::Location, check::Bind, check::DeadSymbols, check::BeginFunction, check::EndFunction, check::EndAnalysis, check::EndOfTranslationUnit, eval::Call, eval::Assume, check::LiveSymbols, check::RegionChanges, check::PointerEscape, check::ConstPointerEscape, check::Event< ImplicitNullDerefEvent >, check::ASTDecl< FunctionDecl > >
static void _register (CHECKER *checker, CheckerManager &mgr)
 
- Static Public Member Functions inherited from clang::ento::check::PreStmt< ReturnStmt >
static void _register (CHECKER *checker, CheckerManager &mgr)
 
- Protected Member Functions inherited from clang::ProgramPointTag
const void * getTagKind ()
 Used to implement 'isKind' in subclasses. More...
 

Detailed Description

This checker documents the callback functions checkers can use to implement the custom handling of the specific events during path exploration as well as reporting bugs.

Most of the callbacks are targeted at path-sensitive checking.

See also
CheckerContext

Definition at line 37 of file CheckerDocumentation.cpp.

Member Function Documentation

◆ checkASTDecl()

void clang::ento::CheckerDocumentation::checkASTDecl ( const FunctionDecl D,
AnalysisManager Mgr,
BugReporter BR 
) const
inline

Check every declaration in the AST.

An AST traversal callback, which should only be used when the checker is not path sensitive. It will be called for every Declaration in the AST and can be specialized to only be called on subclasses of Decl, for example, FunctionDecl.

check::ASTDecl<FunctionDecl>

Definition at line 308 of file CheckerDocumentation.cpp.

◆ checkBeginFunction()

void clang::ento::CheckerDocumentation::checkBeginFunction ( CheckerContext Ctx) const
inline

Called when the analyzer core starts analyzing a function, regardless of whether it is analyzed at the top level or is inlined.

check::BeginFunction

Definition at line 171 of file CheckerDocumentation.cpp.

◆ checkBind()

void clang::ento::CheckerDocumentation::checkBind ( SVal  Loc,
SVal  Val,
const Stmt S,
CheckerContext  
) const
inline

Called on binding of a value to a location.

Parameters
LocThe value of the location (pointer).
ValThe value which will be stored at the location Loc.
SThe bind is performed while processing the statement S.

check::Bind

Definition at line 148 of file CheckerDocumentation.cpp.

◆ checkBranchCondition()

void clang::ento::CheckerDocumentation::checkBranchCondition ( const Stmt Condition,
CheckerContext Ctx 
) const
inline

Pre-visit of the condition statement of a branch (such as IfStmt).

Definition at line 127 of file CheckerDocumentation.cpp.

◆ checkConstPointerEscape()

ProgramStateRef clang::ento::CheckerDocumentation::checkConstPointerEscape ( ProgramStateRef  State,
const InvalidatedSymbols Escaped,
const CallEvent Call,
PointerEscapeKind  Kind 
) const
inline

Called when const pointers escape.

Note: in most cases checkPointerEscape callback is sufficient.

See also
checkPointerEscape

Definition at line 290 of file CheckerDocumentation.cpp.

References State.

◆ checkDeadSymbols()

void clang::ento::CheckerDocumentation::checkDeadSymbols ( SymbolReaper SR,
CheckerContext C 
) const
inline

Called whenever a symbol becomes dead.

This callback should be used by the checkers to aggressively clean up/reduce the checker state, which is important for reducing the overall memory usage. Specifically, if a checker keeps symbol specific information in the sate, it can and should be dropped after the symbol becomes dead. In addition, reporting a bug as soon as the checker becomes dead leads to more precise diagnostics. (For example, one should report that a malloced variable is not freed right after it goes out of scope.)

Parameters
SRThe SymbolReaper object can be queried to determine which symbols are dead.

check::DeadSymbols

Definition at line 164 of file CheckerDocumentation.cpp.

◆ checkEndAnalysis()

void clang::ento::CheckerDocumentation::checkEndAnalysis ( ExplodedGraph G,
BugReporter BR,
ExprEngine Eng 
) const
inline

Called after all the paths in the ExplodedGraph reach end of path.

  • the symbolic execution graph is fully explored.

This callback should be used in cases when a checker needs to have a global view of the information generated on all paths. For example, to compare execution summary/result several paths. See IdempotentOperationChecker for a usage example.

check::EndAnalysis

Definition at line 189 of file CheckerDocumentation.cpp.

◆ checkEndFunction()

void clang::ento::CheckerDocumentation::checkEndFunction ( CheckerContext Ctx) const
inline

Called when the analyzer core reaches the end of a function being analyzed regardless of whether it is analyzed at the top level or is inlined.

check::EndFunction

Definition at line 178 of file CheckerDocumentation.cpp.

◆ checkEndOfTranslationUnit()

void clang::ento::CheckerDocumentation::checkEndOfTranslationUnit ( const TranslationUnitDecl TU,
AnalysisManager Mgr,
BugReporter BR 
) const
inline

Called after analysis of a TranslationUnit is complete.

check::EndOfTranslationUnit

Definition at line 196 of file CheckerDocumentation.cpp.

◆ checkEvent()

void clang::ento::CheckerDocumentation::checkEvent ( ImplicitNullDerefEvent  Event) const
inline

check::Event<ImplicitNullDerefEvent>

Definition at line 298 of file CheckerDocumentation.cpp.

◆ checkLiveSymbols()

void clang::ento::CheckerDocumentation::checkLiveSymbols ( ProgramStateRef  State,
SymbolReaper SR 
) const
inline

Allows modifying SymbolReaper object.

For example, checkers can explicitly register symbols of interest as live. These symbols will not be marked dead and removed.

check::LiveSymbols

Definition at line 232 of file CheckerDocumentation.cpp.

◆ checkLocation()

void clang::ento::CheckerDocumentation::checkLocation ( SVal  Loc,
bool  IsLoad,
const Stmt S,
CheckerContext  
) const
inline

Called on a load from and a store to a location.

The method will be called each time a location (pointer) value is accessed.

Parameters
LocThe value of the location (pointer).
IsLoadThe flag specifying if the location is a store or a load.
SThe load is performed while processing the statement.

check::Location

Definition at line 138 of file CheckerDocumentation.cpp.

◆ checkObjCMessageNil()

void clang::ento::CheckerDocumentation::checkObjCMessageNil ( const ObjCMethodCall M,
CheckerContext C 
) const
inline

Visit an Objective-C message whose receiver is nil.

This will be called when the analyzer core processes a method call whose receiver is definitely nil. In this case, check{Pre/Post}ObjCMessage and check{Pre/Post}Call will not be called.

check::ObjCMessageNil

Definition at line 106 of file CheckerDocumentation.cpp.

◆ checkPointerEscape()

ProgramStateRef clang::ento::CheckerDocumentation::checkPointerEscape ( ProgramStateRef  State,
const InvalidatedSymbols Escaped,
const CallEvent Call,
PointerEscapeKind  Kind 
) const
inline

Called when pointers escape.

This notifies the checkers about pointer escape, which occurs whenever the analyzer cannot track the symbol any more. For example, as a result of assigning a pointer into a global or when it's passed to a function call the analyzer cannot model.

Parameters
StateThe state at the point of escape.
EscapedThe list of escaped symbols.
CallThe corresponding CallEvent, if the symbols escape as parameters to the given call.
KindHow the symbols have escaped.
Returns
Checkers can modify the state by returning a new state.

Definition at line 279 of file CheckerDocumentation.cpp.

References State.

◆ checkPostCall()

void clang::ento::CheckerDocumentation::checkPostCall ( const CallEvent Call,
CheckerContext C 
) const
inline

Post-visit an abstract "call" event.

See also
checkPreObjCMessage()

check::PostCall

Definition at line 124 of file CheckerDocumentation.cpp.

◆ checkPostObjCMessage()

void clang::ento::CheckerDocumentation::checkPostObjCMessage ( const ObjCMethodCall M,
CheckerContext C 
) const
inline

Post-visit the Objective C message.

See also
checkPreObjCMessage()

check::PostObjCMessage

Definition at line 97 of file CheckerDocumentation.cpp.

◆ checkPostStmt()

void clang::ento::CheckerDocumentation::checkPostStmt ( const DeclStmt DS,
CheckerContext C 
) const

Post-visit the Statement.

The method will be called after the analyzer core processes the statement. The notification is performed for every explored CFGElement, which does not include the control flow statements such as IfStmt. The callback can be specialized to be called with any subclass of Stmt.

check::PostStmt<DeclStmt>

Definition at line 313 of file CheckerDocumentation.cpp.

◆ checkPreCall()

void clang::ento::CheckerDocumentation::checkPreCall ( const CallEvent Call,
CheckerContext C 
) const
inline

Pre-visit an abstract "call" event.

This is used for checkers that want to check arguments or attributed behavior for functions and methods no matter how they are being invoked.

Note that this includes ALL cross-body invocations, so if you want to limit your checks to, say, function calls, you should test for that at the beginning of your callback function.

check::PreCall

Definition at line 118 of file CheckerDocumentation.cpp.

◆ checkPreObjCMessage()

void clang::ento::CheckerDocumentation::checkPreObjCMessage ( const ObjCMethodCall M,
CheckerContext C 
) const
inline

Pre-visit the Objective C message.

This will be called before the analyzer core processes the method call. This is called for any action which produces an Objective-C message send, including explicit message syntax and property access.

check::PreObjCMessage

Definition at line 91 of file CheckerDocumentation.cpp.

◆ checkPreStmt()

void clang::ento::CheckerDocumentation::checkPreStmt ( const ReturnStmt DS,
CheckerContext C 
) const
inline

Pre-visit the Statement.

The method will be called before the analyzer core processes the statement. The notification is performed for every explored CFGElement, which does not include the control flow statements such as IfStmt. The callback can be specialized to be called with any subclass of Stmt.

See checkBranchCondition() callback for performing custom processing of the branching statements.

check::PreStmt<ReturnStmt>

Definition at line 72 of file CheckerDocumentation.cpp.

◆ checkRegionChanges()

ProgramStateRef clang::ento::CheckerDocumentation::checkRegionChanges ( ProgramStateRef  State,
const InvalidatedSymbols Invalidated,
ArrayRef< const MemRegion *>  ExplicitRegions,
ArrayRef< const MemRegion *>  Regions,
const LocationContext LCtx,
const CallEvent Call 
) const
inline

Called when the contents of one or more regions change.

This can occur in many different ways: an explicit bind, a blanket invalidation of the region contents, or by passing a region to a function call whose behavior the analyzer cannot model perfectly.

Parameters
StateThe current program state.
InvalidatedA set of all symbols potentially touched by the change.
ExplicitRegionsThe regions explicitly requested for invalidation. For a function call, this would be the arguments. For a bind, this would be the region being bound to.
RegionsThe transitive closure of regions accessible from, ExplicitRegions, i.e. all regions that may have been touched by this change. For a simple bind, this list will be the same as ExplicitRegions, since a bind does not affect the contents of anything accessible through the base region.
LCtxLocationContext that is useful for getting various contextual info, like callstack, CFG etc.
CallThe opaque call triggering this invalidation. Will be 0 if the change was not triggered by a call.

check::RegionChanges

Definition at line 257 of file CheckerDocumentation.cpp.

References State.

◆ evalAssume()

ProgramStateRef clang::ento::CheckerDocumentation::evalAssume ( ProgramStateRef  State,
SVal  Cond,
bool  Assumption 
) const
inline

Handles assumptions on symbolic values.

This method is called when a symbolic expression is assumed to be true or false. For example, the assumptions are performed when evaluating a condition at a branch. The callback allows checkers track the assumptions performed on the symbols of interest and change the state accordingly.

eval::Assume

Definition at line 223 of file CheckerDocumentation.cpp.

References State.

◆ evalCall()

bool clang::ento::CheckerDocumentation::evalCall ( const CallExpr CE,
CheckerContext C 
) const
inline

Evaluates function call.

The analysis core threats all function calls in the same way. However, some functions have special meaning, which should be reflected in the program state. This callback allows a checker to provide domain specific knowledge about the particular functions it knows about.

Returns
true if the call has been successfully evaluated and false otherwise. Note, that only one checker can evaluate a call. If more than one checker claims that they can evaluate the same call the first one wins.

eval::Call

Definition at line 213 of file CheckerDocumentation.cpp.


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