clang 19.0.0git
ASTOps.h
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1//===-- ASTOps.h -------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// Operations on AST nodes that are used in flow-sensitive analysis.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_CLANG_ANALYSIS_FLOWSENSITIVE_ASTOPS_H
14#define LLVM_CLANG_ANALYSIS_FLOWSENSITIVE_ASTOPS_H
15
16#include "clang/AST/Decl.h"
17#include "clang/AST/Expr.h"
19#include "clang/AST/Type.h"
21#include "llvm/ADT/DenseSet.h"
22#include "llvm/ADT/SetVector.h"
23
24namespace clang {
25namespace dataflow {
26
27/// Skip past nodes that the CFG does not emit. These nodes are invisible to
28/// flow-sensitive analysis, and should be ignored as they will effectively not
29/// exist.
30///
31/// * `ParenExpr` - The CFG takes the operator precedence into account, but
32/// otherwise omits the node afterwards.
33///
34/// * `ExprWithCleanups` - The CFG will generate the appropriate calls to
35/// destructors and then omit the node.
36///
37const Expr &ignoreCFGOmittedNodes(const Expr &E);
38const Stmt &ignoreCFGOmittedNodes(const Stmt &S);
39
40/// A set of `FieldDecl *`. Use `SmallSetVector` to guarantee deterministic
41/// iteration order.
43
44/// Returns the set of all fields in the type.
46
47/// Returns whether `Fields` and `FieldLocs` contain the same fields.
48bool containsSameFields(const FieldSet &Fields,
49 const RecordStorageLocation::FieldToLoc &FieldLocs);
50
51/// Helper class for initialization of a record with an `InitListExpr`.
52/// `InitListExpr::inits()` contains the initializers for both the base classes
53/// and the fields of the record; this helper class separates these out into two
54/// different lists. In addition, it deals with special cases associated with
55/// unions.
57public:
58 // `InitList` must have record type.
59 RecordInitListHelper(const InitListExpr *InitList);
60 RecordInitListHelper(const CXXParenListInitExpr *ParenInitList);
61
62 // Base classes with their associated initializer expressions.
64 return BaseInits;
65 }
66
67 // Fields with their associated initializer expressions.
69 return FieldInits;
70 }
71
72private:
73 RecordInitListHelper(QualType Ty, std::vector<const FieldDecl *> Fields,
74 ArrayRef<Expr *> Inits);
75
78
79 // We potentially synthesize an `ImplicitValueInitExpr` for unions. It's a
80 // member variable because we store a pointer to it in `FieldInits`.
81 std::optional<ImplicitValueInitExpr> ImplicitValueInitForUnion;
82};
83
84/// Specialization of `RecursiveASTVisitor` that visits those nodes that are
85/// relevant to the dataflow analysis; generally, these are the ones that also
86/// appear in the CFG.
87/// To start the traversal, call `TraverseStmt()` on the statement or body of
88/// the function to analyze. Don't call `TraverseDecl()` on the function itself;
89/// this won't work as `TraverseDecl()` contains code to avoid traversing nested
90/// functions.
91template <class Derived>
92class AnalysisASTVisitor : public RecursiveASTVisitor<Derived> {
93public:
94 bool shouldVisitImplicitCode() { return true; }
95
96 bool shouldVisitLambdaBody() const { return false; }
97
99 // Don't traverse nested record or function declarations.
100 // - We won't be analyzing code contained in these anyway
101 // - We don't model fields that are used only in these nested declaration,
102 // so trying to propagate a result object to initializers of such fields
103 // would cause an error.
104 if (isa_and_nonnull<RecordDecl>(D) || isa_and_nonnull<FunctionDecl>(D))
105 return true;
106
108 }
109
110 // Don't traverse expressions in unevaluated contexts, as we don't model
111 // fields that are only used in these.
112 // Note: The operand of the `noexcept` operator is an unevaluated operand, but
113 // nevertheless it appears in the Clang CFG, so we don't exclude it here.
116 bool TraverseCXXTypeidExpr(CXXTypeidExpr *) { return true; }
118 return true;
119 }
120
122 // `RecursiveASTVisitor` doesn't traverse holding variables for
123 // `BindingDecl`s by itself, so we need to tell it to.
124 if (VarDecl *HoldingVar = BD->getHoldingVar())
125 TraverseDecl(HoldingVar);
127 }
128};
129
130/// A collection of several types of declarations, all referenced from the same
131/// function.
133 /// Non-static member variables.
135 /// All variables with static storage duration, notably including static
136 /// member variables and static variables declared within a function.
138 /// Free functions and member functions which are referenced (but not
139 /// necessarily called).
141};
142
143/// Returns declarations that are declared in or referenced from `FD`.
145
146/// Returns declarations that are declared in or referenced from `S`.
148
149} // namespace dataflow
150} // namespace clang
151
152#endif // LLVM_CLANG_ANALYSIS_FLOWSENSITIVE_ASTOPS_H
const Decl * D
Expr * E
C Language Family Type Representation.
A binding in a decomposition declaration.
Definition: DeclCXX.h:4107
VarDecl * getHoldingVar() const
Get the variable (if any) that holds the value of evaluating the binding.
Definition: DeclCXX.cpp:3344
Represents a list-initialization with parenthesis.
Definition: ExprCXX.h:4966
A C++ typeid expression (C++ [expr.typeid]), which gets the type_info that corresponds to the supplie...
Definition: ExprCXX.h:845
Decl - This represents one declaration (or definition), e.g.
Definition: DeclBase.h:86
Represents a function declaration or definition.
Definition: Decl.h:1971
Describes an C or C++ initializer list.
Definition: Expr.h:5010
A (possibly-)qualified type.
Definition: Type.h:942
A class that does preorder or postorder depth-first traversal on the entire Clang AST and visits each...
bool TraverseDecl(Decl *D)
Recursively visit a declaration, by dispatching to Traverse*Decl() based on the argument's dynamic ty...
Stmt - This represents one statement.
Definition: Stmt.h:84
The base class of the type hierarchy.
Definition: Type.h:1826
UnaryExprOrTypeTraitExpr - expression with either a type or (unevaluated) expression operand.
Definition: Expr.h:2573
Represents a variable declaration or definition.
Definition: Decl.h:918
Specialization of RecursiveASTVisitor that visits those nodes that are relevant to the dataflow analy...
Definition: ASTOps.h:92
bool TraverseDecltypeTypeLoc(DecltypeTypeLoc)
Definition: ASTOps.h:114
bool shouldVisitLambdaBody() const
Definition: ASTOps.h:96
bool TraverseBindingDecl(BindingDecl *BD)
Definition: ASTOps.h:121
bool TraverseTypeOfExprTypeLoc(TypeOfExprTypeLoc)
Definition: ASTOps.h:115
bool TraverseCXXTypeidExpr(CXXTypeidExpr *)
Definition: ASTOps.h:116
bool TraverseUnaryExprOrTypeTraitExpr(UnaryExprOrTypeTraitExpr *)
Definition: ASTOps.h:117
Helper class for initialization of a record with an InitListExpr.
Definition: ASTOps.h:56
ArrayRef< std::pair< const FieldDecl *, Expr * > > field_inits() const
Definition: ASTOps.h:68
ArrayRef< std::pair< const CXXBaseSpecifier *, Expr * > > base_inits() const
Definition: ASTOps.h:63
llvm::DenseMap< const ValueDecl *, StorageLocation * > FieldToLoc
ReferencedDecls getReferencedDecls(const FunctionDecl &FD)
Returns declarations that are declared in or referenced from FD.
Definition: ASTOps.cpp:270
const Expr & ignoreCFGOmittedNodes(const Expr &E)
Skip past nodes that the CFG does not emit.
Definition: ASTOps.cpp:34
FieldSet getObjectFields(QualType Type)
Returns the set of all fields in the type.
Definition: ASTOps.cpp:74
bool containsSameFields(const FieldSet &Fields, const RecordStorageLocation::FieldToLoc &FieldLocs)
Returns whether Fields and FieldLocs contain the same fields.
Definition: ASTOps.cpp:80
The JSON file list parser is used to communicate input to InstallAPI.
A collection of several types of declarations, all referenced from the same function.
Definition: ASTOps.h:132
llvm::DenseSet< const VarDecl * > Globals
All variables with static storage duration, notably including static member variables and static vari...
Definition: ASTOps.h:137
llvm::DenseSet< const FunctionDecl * > Functions
Free functions and member functions which are referenced (but not necessarily called).
Definition: ASTOps.h:140
FieldSet Fields
Non-static member variables.
Definition: ASTOps.h:134