clang  16.0.0git
Classes | Typedefs | Enumerations | Functions | Variables
clang::dataflow Namespace Reference

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...
 
struct  AnalysisContext
 Holds data structures required for running dataflow analysis. More...
 
class  ASTMatchSwitchBuilder
 Collects cases of a "match switch": a collection of matchers paired with callbacks, which together define a switch that can be applied to a node whose type derives from BaseT. More...
 
class  AtomicBoolValue
 Models an atomic boolean. More...
 
struct  backward_analysis_tag
 
class  BiconditionalValue
 Models a boolean biconditional. More...
 
struct  BooleanFormula
 A boolean formula in conjunctive normal form. More...
 
class  BoolValue
 Models a boolean. More...
 
class  CFGMatchSwitchBuilder
 Collects cases of a "match switch": a collection of matchers paired with callbacks, which together define a switch that can be applied to an AST node contained in a CFG element. More...
 
class  ChromiumCheckModel
 Models the behavior of Chromium's CHECK, DCHECK, etc. More...
 
class  ConjunctionValue
 Models a boolean conjunction. More...
 
struct  ContextSensitiveOptions
 
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  DataflowAnalysisOptions
 
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
 
struct  HasTransferFor
 
struct  HasTransferFor< AnalysisT, LatticeT, InputT, std::void_t< decltype(std::declval< AnalysisT >().transfer(std::declval< const InputT * >(), std::declval< LatticeT & >(), std::declval< Environment & >()))> >
 
class  ImplicationValue
 Models a boolean implication. More...
 
class  IntegerValue
 Models an integer. More...
 
class  MapLattice
 A lattice that maps keys to individual lattice elements. More...
 
class  NegationValue
 Models a boolean negation. More...
 
class  NoopAnalysis
 
class  NoopLattice
 Trivial lattice for dataflow analysis with exactly one element. 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  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  TransferOptions
 
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  UncheckedOptionalAccessDiagnoser
 
class  UncheckedOptionalAccessModel
 Dataflow analysis that models whether optionals hold values or not. 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 State , typename Result = void>
using CFGMatchSwitch = std::function< Result(const CFGElement &, ASTContext &, State &)>
 
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 T >
using MatchSwitchMatcher = ast_matchers::internal::Matcher< T >
 
template<typename T , typename State , typename Result = void>
using MatchSwitchAction = std::function< Result(const T *, const ast_matchers::MatchFinder::MatchResult &, State &)>
 
template<typename BaseT , typename State , typename Result = void>
using ASTMatchSwitch = std::function< Result(const BaseT &, ASTContext &, State &)>
 
template<typename State , typename Result = void>
using MatchSwitch = ASTMatchSwitch< Stmt, State, Result >
 
template<typename State , typename Result = void>
using MatchSwitchBuilder = ASTMatchSwitchBuilder< Stmt, State, Result >
 
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, std::function< void(const CFGElement &, const DataflowAnalysisState< typename AnalysisT::Lattice > &)> PostVisitCFG=nullptr)
 Performs dataflow analysis and returns a mapping from basic block IDs to dataflow analysis states that model the respective basic blocks. More...
 
const ExprignoreCFGOmittedNodes (const Expr &E)
 Skip past nodes that the CFG does not emit. More...
 
const StmtignoreCFGOmittedNodes (const Stmt &S)
 
llvm::DenseSet< const FieldDecl * > getObjectFields (QualType Type)
 Returns the set of all fields in the type. More...
 
llvm::StringRef debugString (Value::Kind Kind)
 Returns a string representation of a value kind. More...
 
llvm::StringRef debugString (Solver::Result::Assignment Assignment)
 Returns a string representation of a boolean assignment to true or false. More...
 
llvm::StringRef debugString (Solver::Result::Status Status)
 Returns a string representation of the result status of a SAT check. More...
 
std::string debugString (const BoolValue &B, llvm::DenseMap< const AtomicBoolValue *, std::string > AtomNames={{}})
 Returns a string representation for the boolean value B. More...
 
std::string debugString (const llvm::DenseSet< BoolValue * > &Constraints, llvm::DenseMap< const AtomicBoolValue *, std::string > AtomNames={{}})
 Returns a string representation for Constraints - a collection of boolean formulas. More...
 
std::string debugString (ArrayRef< BoolValue * > Constraints, const Solver::Result &Result, llvm::DenseMap< const AtomicBoolValue *, std::string > AtomNames={{}})
 Returns a string representation for Constraints - a collection of boolean formulas and the Result of satisfiability checking. More...
 
std::string debugString (const llvm::DenseSet< BoolValue * > &Constraints, const Solver::Result &Result, llvm::DenseMap< const AtomicBoolValue *, std::string > AtomNames={{}})
 
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::ostream & operator<< (std::ostream &OS, const NoopLattice &)
 
void transfer (const StmtToEnvMap &StmtToEnv, const Stmt &S, Environment &Env, TransferOptions Options)
 Evaluates S and updates Env accordingly. More...
 
TypeErasedDataflowAnalysisState transferBlock (const ControlFlowContext &CFCtx, llvm::ArrayRef< llvm::Optional< TypeErasedDataflowAnalysisState >> BlockStates, const CFGBlock &Block, const Environment &InitEnv, TypeErasedDataflowAnalysis &Analysis, std::function< void(const CFGElement &, const TypeErasedDataflowAnalysisState &)> PostVisitCFG=nullptr)
 Transfers the state of a basic block by evaluating each of its elements 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, std::function< void(const CFGElement &, const TypeErasedDataflowAnalysisState &)> PostVisitCFG=nullptr)
 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, VintersectDenseMaps (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 areEquivalentIndirectionValues (Value *Val1, Value *Val2)
 
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 ValuemergeDistinctValues (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...
 
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 BoolValueevaluateBooleanEquality (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 CFGBlock &Block, AnalysisContext &AC)
 Computes the input state for a given basic block by joining the output states of its predecessors. More...
 
void builtinTransferStatement (const CFGStmt &Elt, TypeErasedDataflowAnalysisState &InputState, AnalysisContext &AC)
 Built-in transfer function for CFGStmt. More...
 
void builtinTransferInitializer (const CFGInitializer &Elt, TypeErasedDataflowAnalysisState &InputState)
 Built-in transfer function for CFGInitializer. More...
 
void builtinTransfer (const CFGElement &Elt, TypeErasedDataflowAnalysisState &State, AnalysisContext &AC)
 
TypeErasedDataflowAnalysisState transferCFGBlock (const CFGBlock &Block, AnalysisContext &AC, std::function< void(const CFGElement &, const TypeErasedDataflowAnalysisState &)> PostVisitCFG=nullptr)
 Transfers State by evaluating each element in the Block based on the AC.Analysis specified. 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

◆ ASTMatchSwitch

template<typename BaseT , typename State , typename Result = void>
using clang::dataflow::ASTMatchSwitch = typedef std::function<Result(const BaseT &, ASTContext &, State &)>

Definition at line 60 of file MatchSwitch.h.

◆ CFGMatchSwitch

template<typename State , typename Result = void>
using clang::dataflow::CFGMatchSwitch = typedef std::function<Result(const CFGElement &, ASTContext &, State &)>

Definition at line 34 of file CFGMatchSwitch.h.

◆ 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 , typename Result = void>
using clang::dataflow::MatchSwitch = typedef ASTMatchSwitch<Stmt, State, Result>

Definition at line 65 of file MatchSwitch.h.

◆ MatchSwitchAction

template<typename T , typename State , typename Result = void>
using clang::dataflow::MatchSwitchAction = typedef std::function<Result( const T *, const ast_matchers::MatchFinder::MatchResult &, State &)>

Definition at line 56 of file MatchSwitch.h.

◆ MatchSwitchBuilder

template<typename State , typename Result = void>
using clang::dataflow::MatchSwitchBuilder = typedef ASTMatchSwitchBuilder<Stmt, State, Result>

Definition at line 167 of file MatchSwitch.h.

◆ MatchSwitchMatcher

template<typename T >
using clang::dataflow::MatchSwitchMatcher = typedef ast_matchers::internal::Matcher<T>

Definition at line 52 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 112 of file MapLattice.h.

Enumeration Type Documentation

◆ LatticeJoinEffect

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

Enumerator
Unchanged 
Changed 

Definition at line 21 of file DataflowLattice.h.

◆ SkipPast

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

◆ areEquivalentIndirectionValues()

static bool clang::dataflow::areEquivalentIndirectionValues ( Value Val1,
Value Val2 
)
static

Definition at line 52 of file DataflowEnvironment.cpp.

Referenced by equivalentValues(), and mergeDistinctValues().

◆ 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 63 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)

◆ 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.

◆ builtinTransfer()

void clang::dataflow::builtinTransfer ( const CFGElement Elt,
TypeErasedDataflowAnalysisState State,
AnalysisContext AC 
)

◆ builtinTransferInitializer()

void clang::dataflow::builtinTransferInitializer ( const CFGInitializer Elt,
TypeErasedDataflowAnalysisState InputState 
)

◆ builtinTransferStatement()

void clang::dataflow::builtinTransferStatement ( const CFGStmt Elt,
TypeErasedDataflowAnalysisState InputState,
AnalysisContext AC 
)

Built-in transfer function for CFGStmt.

Definition at line 266 of file TypeErasedDataflowAnalysis.cpp.

Referenced by builtinTransfer().

◆ computeBlockInputState()

static TypeErasedDataflowAnalysisState clang::dataflow::computeBlockInputState ( const CFGBlock Block,
AnalysisContext AC 
)
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 AC.BlockStates that are set to llvm::None represent basic blocks that are not evaluated yet.

Definition at line 187 of file TypeErasedDataflowAnalysis.cpp.

References clang::dataflow::AnalysisContext::Analysis, clang::Block, blockIndexInPredecessor(), clang::dataflow::AnalysisContext::BlockStates, clang::dataflow::TypeErasedDataflowAnalysis::builtinTransferOptions(), clang::dataflow::AnalysisContext::CFCtx, clang::dataflow::TypeErasedDataflowAnalysisState::Env, clang::dataflow::ControlFlowContext::getStmtToBlock(), clang::dataflow::AnalysisContext::InitEnv, clang::dataflow::TypeErasedDataflowAnalysisState::Lattice, and clang::StmtVisitorBase< Ptr, ImplClass, RetTy, ParamTys >::Visit().

Referenced by transferCFGBlock().

◆ debugString() [1/7]

std::string clang::dataflow::debugString ( ArrayRef< BoolValue * >  Constraints,
const Solver::Result Result,
llvm::DenseMap< const AtomicBoolValue *, std::string AtomNames = {{}} 
)

Returns a string representation for Constraints - a collection of boolean formulas and the Result of satisfiability checking.

Atomic booleans appearing in Constraints and Result are assigned to labels either specified in AtomNames or created by default rules as B0, B1, ...

Requirements:

Names assigned to atoms should not be repeated in AtomNames.

Definition at line 250 of file DebugSupport.cpp.

◆ debugString() [2/7]

std::string clang::dataflow::debugString ( const BoolValue B,
llvm::DenseMap< const AtomicBoolValue *, std::string AtomNames = {{}} 
)

Returns a string representation for the boolean value B.

Atomic booleans appearing in the boolean value B are assigned to labels either specified in AtomNames or created by default rules as B0, B1, ...

Requirements:

Names assigned to atoms should not be repeated in AtomNames.

Definition at line 238 of file DebugSupport.cpp.

◆ debugString() [3/7]

std::string clang::dataflow::debugString ( const llvm::DenseSet< BoolValue * > &  Constraints,
const Solver::Result Result,
llvm::DenseMap< const AtomicBoolValue *, std::string AtomNames = {{}} 
)
inline

Definition at line 76 of file DebugSupport.h.

◆ debugString() [4/7]

std::string clang::dataflow::debugString ( const llvm::DenseSet< BoolValue * > &  Constraints,
llvm::DenseMap< const AtomicBoolValue *, std::string AtomNames = {{}} 
)

Returns a string representation for Constraints - a collection of boolean formulas.

Atomic booleans appearing in the boolean value Constraints are assigned to labels either specified in AtomNames or created by default rules as B0, B1, ...

Requirements:

Names assigned to atoms should not be repeated in AtomNames.

Definition at line 244 of file DebugSupport.cpp.

◆ debugString() [5/7]

llvm::StringRef clang::dataflow::debugString ( Solver::Result::Assignment  Assignment)

Returns a string representation of a boolean assignment to true or false.

Definition at line 61 of file DebugSupport.cpp.

References clang::dataflow::Solver::Result::AssignedFalse, clang::dataflow::Solver::Result::AssignedTrue, and clang::prec::Assignment.

◆ debugString() [6/7]

llvm::StringRef clang::dataflow::debugString ( Solver::Result::Status  Status)

Returns a string representation of the result status of a SAT check.

Definition at line 71 of file DebugSupport.cpp.

◆ debugString() [7/7]

llvm::StringRef clang::dataflow::debugString ( Value::Kind  Kind)

◆ 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 65 of file DataflowEnvironment.cpp.

References areEquivalentIndirectionValues(), and 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

◆ getObjectFields()

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

Returns the set of all fields in the type.

Gets the set of all fields in the type.

Definition at line 398 of file DataflowAnalysisContext.cpp.

References getFieldsFromClassHierarchy().

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

◆ 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 363 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 374 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

◆ 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 41 of file DataflowEnvironment.cpp.

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

◆ isCheckLikeMethod()

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

◆ makeCanonicalBoolValuePair()

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

◆ 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 77 of file DataflowEnvironment.cpp.

References clang::dataflow::Environment::addToFlowCondition(), areEquivalentIndirectionValues(), clang::dataflow::Environment::createValue(), clang::dataflow::Environment::getFlowConditionToken(), clang::dataflow::Environment::makeAnd(), clang::dataflow::Environment::makeAtomicBoolValue(), clang::dataflow::Environment::makeIff(), 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

◆ notLit()

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

Returns the negated literal !L.

Definition at line 68 of file WatchedLiteralsSolver.cpp.

◆ operator<<() [1/3]

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

Definition at line 116 of file MapLattice.h.

References string().

◆ operator<<() [2/3]

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

Definition at line 129 of file MapLattice.h.

References string().

◆ operator<<() [3/3]

std::ostream& clang::dataflow::operator<< ( std::ostream &  OS,
const NoopLattice  
)
inline

Definition at line 34 of file NoopLattice.h.

◆ posLit()

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

◆ 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,
std::function< void(const CFGElement &, const DataflowAnalysisState< typename AnalysisT::Lattice > &)>  PostVisitCFG = nullptr 
)

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. Otherwise, calls PostVisitCFG on each CFG element with the final analysis results at that program point.

Definition at line 149 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,
std::function< void(const CFGElement &, const TypeErasedDataflowAnalysisState &)>  PostVisitCFG = nullptr 
)

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. Otherwise, calls PostVisitCFG on each CFG element with the final analysis results at that program point.

Definition at line 373 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, min(), clang::CFG::size(), transferCFGBlock(), and clang::dataflow::TypeErasedDataflowAnalysis::typeErasedInitialElement().

Referenced by runDataflowAnalysis().

◆ transfer()

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

Evaluates S and updates Env accordingly.

Requirements:

S must not be ParenExpr or ExprWithCleanups.

Definition at line 711 of file Transfer.cpp.

Referenced by clang::dataflow::DataflowAnalysis< NoopAnalysis, NoopLattice >::transferTypeErased().

◆ transferBlock()

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

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

PostVisitCFG (if provided) will be applied to each element 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 360 of file TypeErasedDataflowAnalysis.cpp.

References clang::Block, and transferCFGBlock().

◆ transferCFGBlock()

TypeErasedDataflowAnalysisState clang::dataflow::transferCFGBlock ( const CFGBlock Block,
AnalysisContext AC,
std::function< void(const CFGElement &, const TypeErasedDataflowAnalysisState &)>  PostVisitCFG = nullptr 
)

Transfers State by evaluating each element in the Block based on the AC.Analysis specified.

Built-in transfer functions (if the option for ApplyBuiltinTransfer is set by the analysis) will be applied to the element before evaluation by the user-specified analysis. PostVisitCFG (if provided) will be applied to the element after evaluation by the user-specified analysis.

Definition at line 338 of file TypeErasedDataflowAnalysis.cpp.

References clang::dataflow::AnalysisContext::Analysis, clang::Block, builtinTransfer(), clang::dataflow::TypeErasedDataflowAnalysis::builtinTransferOptions(), computeBlockInputState(), State, and clang::dataflow::TypeErasedDataflowAnalysis::transferTypeErased().

Referenced by runTypeErasedDataflowAnalysis(), and transferBlock().

◆ var()

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

Variable Documentation

◆ MaxCompositeValueDepth

constexpr int clang::dataflow::MaxCompositeValueDepth = 3
staticconstexpr

Definition at line 36 of file DataflowEnvironment.cpp.

◆ MaxCompositeValueSize

constexpr int clang::dataflow::MaxCompositeValueSize = 1000
staticconstexpr

Definition at line 37 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().