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//===- ConstructionContext.h - CFG constructor information ------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines the ConstructionContext class and its sub-classes,
// which represent various different ways of constructing C++ objects
// with the additional information the users may want to know about
// the constructor.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_ANALYSIS_CONSTRUCTIONCONTEXT_H
#define LLVM_CLANG_ANALYSIS_CONSTRUCTIONCONTEXT_H
#include "clang/Analysis/Support/BumpVector.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/ExprObjC.h"
namespace clang {
/// Represents a single point (AST node) in the program that requires attention
/// during construction of an object. ConstructionContext would be represented
/// as a list of such items.
class ConstructionContextItem {
public:
enum ItemKind {
VariableKind,
NewAllocatorKind,
ReturnKind,
MaterializationKind,
TemporaryDestructorKind,
ElidedDestructorKind,
ElidableConstructorKind,
ArgumentKind,
LambdaCaptureKind,
STATEMENT_WITH_INDEX_KIND_BEGIN = ArgumentKind,
STATEMENT_WITH_INDEX_KIND_END = LambdaCaptureKind,
STATEMENT_KIND_BEGIN = VariableKind,
STATEMENT_KIND_END = LambdaCaptureKind,
InitializerKind,
INITIALIZER_KIND_BEGIN = InitializerKind,
INITIALIZER_KIND_END = InitializerKind
};
LLVM_DUMP_METHOD static StringRef getKindAsString(ItemKind K) {
switch (K) {
case VariableKind: return "construct into local variable";
case NewAllocatorKind: return "construct into new-allocator";
case ReturnKind: return "construct into return address";
case MaterializationKind: return "materialize temporary";
case TemporaryDestructorKind: return "destroy temporary";
case ElidedDestructorKind: return "elide destructor";
case ElidableConstructorKind: return "elide constructor";
case ArgumentKind: return "construct into argument";
case LambdaCaptureKind:
return "construct into lambda captured variable";
case InitializerKind: return "construct into member variable";
};
llvm_unreachable("Unknown ItemKind");
}
private:
const void *const Data;
const ItemKind Kind;
const unsigned Index = 0;
bool hasStatement() const {
return Kind >= STATEMENT_KIND_BEGIN &&
Kind <= STATEMENT_KIND_END;
}
bool hasIndex() const {
return Kind >= STATEMENT_WITH_INDEX_KIND_BEGIN &&
Kind <= STATEMENT_WITH_INDEX_KIND_END;
}
bool hasInitializer() const {
return Kind >= INITIALIZER_KIND_BEGIN &&
Kind <= INITIALIZER_KIND_END;
}
public:
// ConstructionContextItem should be simple enough so that it was easy to
// re-construct it from the AST node it captures. For that reason we provide
// simple implicit conversions from all sorts of supported AST nodes.
ConstructionContextItem(const DeclStmt *DS)
: Data(DS), Kind(VariableKind) {}
ConstructionContextItem(const CXXNewExpr *NE)
: Data(NE), Kind(NewAllocatorKind) {}
ConstructionContextItem(const ReturnStmt *RS)
: Data(RS), Kind(ReturnKind) {}
ConstructionContextItem(const MaterializeTemporaryExpr *MTE)
: Data(MTE), Kind(MaterializationKind) {}
ConstructionContextItem(const CXXBindTemporaryExpr *BTE,
bool IsElided = false)
: Data(BTE),
Kind(IsElided ? ElidedDestructorKind : TemporaryDestructorKind) {}
ConstructionContextItem(const CXXConstructExpr *CE)
: Data(CE), Kind(ElidableConstructorKind) {}
ConstructionContextItem(const CallExpr *CE, unsigned Index)
: Data(CE), Kind(ArgumentKind), Index(Index) {}
ConstructionContextItem(const CXXConstructExpr *CE, unsigned Index)
: Data(CE), Kind(ArgumentKind), Index(Index) {}
ConstructionContextItem(const CXXInheritedCtorInitExpr *CE, unsigned Index)
: Data(CE), Kind(ArgumentKind), Index(Index) {}
ConstructionContextItem(const ObjCMessageExpr *ME, unsigned Index)
: Data(ME), Kind(ArgumentKind), Index(Index) {}
// A polymorphic version of the previous calls with dynamic type check.
ConstructionContextItem(const Expr *E, unsigned Index)
: Data(E), Kind(ArgumentKind), Index(Index) {
assert(isa<CallExpr>(E) || isa<CXXConstructExpr>(E) ||
isa<CXXDeleteExpr>(E) || isa<CXXInheritedCtorInitExpr>(E) ||
isa<ObjCMessageExpr>(E));
}
ConstructionContextItem(const CXXCtorInitializer *Init)
: Data(Init), Kind(InitializerKind), Index(0) {}
ConstructionContextItem(const LambdaExpr *LE, unsigned Index)
: Data(LE), Kind(LambdaCaptureKind), Index(Index) {}
ItemKind getKind() const { return Kind; }
LLVM_DUMP_METHOD StringRef getKindAsString() const {
return getKindAsString(getKind());
}
/// The construction site - the statement that triggered the construction
/// for one of its parts. For instance, stack variable declaration statement
/// triggers construction of itself or its elements if it's an array,
/// new-expression triggers construction of the newly allocated object(s).
const Stmt *getStmt() const {
assert(hasStatement());
return static_cast<const Stmt *>(Data);
}
const Stmt *getStmtOrNull() const {
return hasStatement() ? getStmt() : nullptr;
}
/// The construction site is not necessarily a statement. It may also be a
/// CXXCtorInitializer, which means that a member variable is being
/// constructed during initialization of the object that contains it.
const CXXCtorInitializer *getCXXCtorInitializer() const {
assert(hasInitializer());
return static_cast<const CXXCtorInitializer *>(Data);
}
/// If a single trigger statement triggers multiple constructors, they are
/// usually being enumerated. This covers function argument constructors
/// triggered by a call-expression and items in an initializer list triggered
/// by an init-list-expression.
unsigned getIndex() const {
// This is a fairly specific request. Let's make sure the user knows
// what he's doing.
assert(hasIndex());
return Index;
}
void Profile(llvm::FoldingSetNodeID &ID) const {
ID.AddPointer(Data);
ID.AddInteger(Kind);
ID.AddInteger(Index);
}
bool operator==(const ConstructionContextItem &Other) const {
// For most kinds the Index comparison is trivially true, but
// checking kind separately doesn't seem to be less expensive
// than checking Index. Same in operator<().
return std::make_tuple(Data, Kind, Index) ==
std::make_tuple(Other.Data, Other.Kind, Other.Index);
}
bool operator<(const ConstructionContextItem &Other) const {
return std::make_tuple(Data, Kind, Index) <
std::make_tuple(Other.Data, Other.Kind, Other.Index);
}
};
/// Construction context can be seen as a linked list of multiple layers.
/// Sometimes a single trigger is not enough to describe the construction
/// site. That's what causing us to have a chain of "partial" construction
/// context layers. Some examples:
/// - A constructor within in an aggregate initializer list within a variable
/// would have a construction context of the initializer list with
/// the parent construction context of a variable.
/// - A constructor for a temporary that needs to be both destroyed
/// and materialized into an elidable copy constructor would have a
/// construction context of a CXXBindTemporaryExpr with the parent
/// construction context of a MaterializeTemproraryExpr.
/// Not all of these are currently supported.
/// Layers are created gradually while traversing the AST, and layers that
/// represent the outmost AST nodes are built first, while the node that
/// immediately contains the constructor would be built last and capture the
/// previous layers as its parents. Construction context captures the last layer
/// (which has links to the previous layers) and classifies the seemingly
/// arbitrary chain of layers into one of the possible ways of constructing
/// an object in C++ for user-friendly experience.
class ConstructionContextLayer {
const ConstructionContextLayer *Parent = nullptr;
ConstructionContextItem Item;
ConstructionContextLayer(ConstructionContextItem Item,
const ConstructionContextLayer *Parent)
: Parent(Parent), Item(Item) {}
public:
static const ConstructionContextLayer *
create(BumpVectorContext &C, const ConstructionContextItem &Item,
const ConstructionContextLayer *Parent = nullptr);
const ConstructionContextItem &getItem() const { return Item; }
const ConstructionContextLayer *getParent() const { return Parent; }
bool isLast() const { return !Parent; }
/// See if Other is a proper initial segment of this construction context
/// in terms of the parent chain - i.e. a few first parents coincide and
/// then the other context terminates but our context goes further - i.e.,
/// we are providing the same context that the other context provides,
/// and a bit more above that.
bool isStrictlyMoreSpecificThan(const ConstructionContextLayer *Other) const;
};
/// ConstructionContext's subclasses describe different ways of constructing
/// an object in C++. The context re-captures the essential parent AST nodes
/// of the CXXConstructExpr it is assigned to and presents these nodes
/// through easy-to-understand accessor methods.
class ConstructionContext {
public:
enum Kind {
SimpleVariableKind,
CXX17ElidedCopyVariableKind,
VARIABLE_BEGIN = SimpleVariableKind,
VARIABLE_END = CXX17ElidedCopyVariableKind,
SimpleConstructorInitializerKind,
CXX17ElidedCopyConstructorInitializerKind,
INITIALIZER_BEGIN = SimpleConstructorInitializerKind,
INITIALIZER_END = CXX17ElidedCopyConstructorInitializerKind,
NewAllocatedObjectKind,
SimpleTemporaryObjectKind,
ElidedTemporaryObjectKind,
TEMPORARY_BEGIN = SimpleTemporaryObjectKind,
TEMPORARY_END = ElidedTemporaryObjectKind,
SimpleReturnedValueKind,
CXX17ElidedCopyReturnedValueKind,
RETURNED_VALUE_BEGIN = SimpleReturnedValueKind,
RETURNED_VALUE_END = CXX17ElidedCopyReturnedValueKind,
ArgumentKind,
LambdaCaptureKind
};
protected:
Kind K;
// Do not make public! These need to only be constructed
// via createFromLayers().
explicit ConstructionContext(Kind K) : K(K) {}
private:
// A helper function for constructing an instance into a bump vector context.
template <typename T, typename... ArgTypes>
static T *create(BumpVectorContext &C, ArgTypes... Args) {
auto *CC = C.getAllocator().Allocate<T>();
return new (CC) T(Args...);
}
// A sub-routine of createFromLayers() that deals with temporary objects
// that need to be materialized. The BTE argument is for the situation when
// the object also needs to be bound for destruction.
static const ConstructionContext *createMaterializedTemporaryFromLayers(
BumpVectorContext &C, const MaterializeTemporaryExpr *MTE,
const CXXBindTemporaryExpr *BTE,
const ConstructionContextLayer *ParentLayer);
// A sub-routine of createFromLayers() that deals with temporary objects
// that need to be bound for destruction. Automatically finds out if the
// object also needs to be materialized and delegates to
// createMaterializedTemporaryFromLayers() if necessary.
static const ConstructionContext *
createBoundTemporaryFromLayers(
BumpVectorContext &C, const CXXBindTemporaryExpr *BTE,
const ConstructionContextLayer *ParentLayer);
public:
/// Consume the construction context layer, together with its parent layers,
/// and wrap it up into a complete construction context. May return null
/// if layers do not form any supported construction context.
static const ConstructionContext *
createFromLayers(BumpVectorContext &C,
const ConstructionContextLayer *TopLayer);
Kind getKind() const { return K; }
virtual const ArrayInitLoopExpr *getArrayInitLoop() const { return nullptr; }
// Only declared to silence -Wnon-virtual-dtor warnings.
virtual ~ConstructionContext() = default;
};
/// An abstract base class for local variable constructors.
class VariableConstructionContext : public ConstructionContext {
const DeclStmt *DS;
protected:
VariableConstructionContext(ConstructionContext::Kind K, const DeclStmt *DS)
: ConstructionContext(K), DS(DS) {
assert(classof(this));
assert(DS);
}
public:
const DeclStmt *getDeclStmt() const { return DS; }
const ArrayInitLoopExpr *getArrayInitLoop() const override {
const auto *Var = cast<VarDecl>(DS->getSingleDecl());
return dyn_cast<ArrayInitLoopExpr>(Var->getInit());
}
static bool classof(const ConstructionContext *CC) {
return CC->getKind() >= VARIABLE_BEGIN &&
CC->getKind() <= VARIABLE_END;
}
};
/// Represents construction into a simple local variable, eg. T var(123);.
/// If a variable has an initializer, eg. T var = makeT();, then the final
/// elidable copy-constructor from makeT() into var would also be a simple
/// variable constructor handled by this class.
class SimpleVariableConstructionContext : public VariableConstructionContext {
friend class ConstructionContext; // Allows to create<>() itself.
explicit SimpleVariableConstructionContext(const DeclStmt *DS)
: VariableConstructionContext(ConstructionContext::SimpleVariableKind,
DS) {}
public:
static bool classof(const ConstructionContext *CC) {
return CC->getKind() == SimpleVariableKind;
}
};
/// Represents construction into a simple variable with an initializer syntax,
/// with a single constructor, eg. T var = makeT();. Such construction context
/// may only appear in C++17 because previously it was split into a temporary
/// object constructor and an elidable simple variable copy-constructor and
/// we were producing separate construction contexts for these constructors.
/// In C++17 we have a single construction context that combines both.
/// Note that if the object has trivial destructor, then this code is
/// indistinguishable from a simple variable constructor on the AST level;
/// in this case we provide a simple variable construction context.
class CXX17ElidedCopyVariableConstructionContext
: public VariableConstructionContext {
const CXXBindTemporaryExpr *BTE;
friend class ConstructionContext; // Allows to create<>() itself.
explicit CXX17ElidedCopyVariableConstructionContext(
const DeclStmt *DS, const CXXBindTemporaryExpr *BTE)
: VariableConstructionContext(CXX17ElidedCopyVariableKind, DS), BTE(BTE) {
assert(BTE);
}
public:
const CXXBindTemporaryExpr *getCXXBindTemporaryExpr() const { return BTE; }
static bool classof(const ConstructionContext *CC) {
return CC->getKind() == CXX17ElidedCopyVariableKind;
}
};
// An abstract base class for constructor-initializer-based constructors.
class ConstructorInitializerConstructionContext : public ConstructionContext {
const CXXCtorInitializer *I;
protected:
explicit ConstructorInitializerConstructionContext(
ConstructionContext::Kind K, const CXXCtorInitializer *I)
: ConstructionContext(K), I(I) {
assert(classof(this));
assert(I);
}
public:
const CXXCtorInitializer *getCXXCtorInitializer() const { return I; }
const ArrayInitLoopExpr *getArrayInitLoop() const override {
return dyn_cast<ArrayInitLoopExpr>(I->getInit());
}
static bool classof(const ConstructionContext *CC) {
return CC->getKind() >= INITIALIZER_BEGIN &&
CC->getKind() <= INITIALIZER_END;
}
};
/// Represents construction into a field or a base class within a bigger object
/// via a constructor initializer, eg. T(): field(123) { ... }.
class SimpleConstructorInitializerConstructionContext
: public ConstructorInitializerConstructionContext {
friend class ConstructionContext; // Allows to create<>() itself.
explicit SimpleConstructorInitializerConstructionContext(
const CXXCtorInitializer *I)
: ConstructorInitializerConstructionContext(
ConstructionContext::SimpleConstructorInitializerKind, I) {}
public:
static bool classof(const ConstructionContext *CC) {
return CC->getKind() == SimpleConstructorInitializerKind;
}
};
/// Represents construction into a field or a base class within a bigger object
/// via a constructor initializer, with a single constructor, eg.
/// T(): field(Field(123)) { ... }. Such construction context may only appear
/// in C++17 because previously it was split into a temporary object constructor
/// and an elidable simple constructor-initializer copy-constructor and we were
/// producing separate construction contexts for these constructors. In C++17
/// we have a single construction context that combines both. Note that if the
/// object has trivial destructor, then this code is indistinguishable from
/// a simple constructor-initializer constructor on the AST level; in this case
/// we provide a simple constructor-initializer construction context.
class CXX17ElidedCopyConstructorInitializerConstructionContext
: public ConstructorInitializerConstructionContext {
const CXXBindTemporaryExpr *BTE;
friend class ConstructionContext; // Allows to create<>() itself.
explicit CXX17ElidedCopyConstructorInitializerConstructionContext(
const CXXCtorInitializer *I, const CXXBindTemporaryExpr *BTE)
: ConstructorInitializerConstructionContext(
CXX17ElidedCopyConstructorInitializerKind, I),
BTE(BTE) {
assert(BTE);
}
public:
const CXXBindTemporaryExpr *getCXXBindTemporaryExpr() const { return BTE; }
static bool classof(const ConstructionContext *CC) {
return CC->getKind() == CXX17ElidedCopyConstructorInitializerKind;
}
};
/// Represents immediate initialization of memory allocated by operator new,
/// eg. new T(123);.
class NewAllocatedObjectConstructionContext : public ConstructionContext {
const CXXNewExpr *NE;
friend class ConstructionContext; // Allows to create<>() itself.
explicit NewAllocatedObjectConstructionContext(const CXXNewExpr *NE)
: ConstructionContext(ConstructionContext::NewAllocatedObjectKind),
NE(NE) {
assert(NE);
}
public:
const CXXNewExpr *getCXXNewExpr() const { return NE; }
static bool classof(const ConstructionContext *CC) {
return CC->getKind() == NewAllocatedObjectKind;
}
};
/// Represents a temporary object, eg. T(123), that does not immediately cross
/// function boundaries "by value"; constructors that construct function
/// value-type arguments or values that are immediately returned from the
/// function that returns a value receive separate construction context kinds.
class TemporaryObjectConstructionContext : public ConstructionContext {
const CXXBindTemporaryExpr *BTE;
const MaterializeTemporaryExpr *MTE;
protected:
explicit TemporaryObjectConstructionContext(
ConstructionContext::Kind K, const CXXBindTemporaryExpr *BTE,
const MaterializeTemporaryExpr *MTE)
: ConstructionContext(K), BTE(BTE), MTE(MTE) {
// Both BTE and MTE can be null here, all combinations possible.
// Even though for now at least one should be non-null, we simply haven't
// implemented the other case yet (this would be a temporary in the middle
// of nowhere that doesn't have a non-trivial destructor).
}
public:
/// CXXBindTemporaryExpr here is non-null as long as the temporary has
/// a non-trivial destructor.
const CXXBindTemporaryExpr *getCXXBindTemporaryExpr() const {
return BTE;
}
/// MaterializeTemporaryExpr is non-null as long as the temporary is actually
/// used after construction, eg. by binding to a reference (lifetime
/// extension), accessing a field, calling a method, or passing it into
/// a function (an elidable copy or move constructor would be a common
/// example) by reference.
const MaterializeTemporaryExpr *getMaterializedTemporaryExpr() const {
return MTE;
}
static bool classof(const ConstructionContext *CC) {
return CC->getKind() >= TEMPORARY_BEGIN && CC->getKind() <= TEMPORARY_END;
}
};
/// Represents a temporary object that is not constructed for the purpose of
/// being immediately copied/moved by an elidable copy/move-constructor.
/// This includes temporary objects "in the middle of nowhere" like T(123) and
/// lifetime-extended temporaries.
class SimpleTemporaryObjectConstructionContext
: public TemporaryObjectConstructionContext {
friend class ConstructionContext; // Allows to create<>() itself.
explicit SimpleTemporaryObjectConstructionContext(
const CXXBindTemporaryExpr *BTE, const MaterializeTemporaryExpr *MTE)
: TemporaryObjectConstructionContext(
ConstructionContext::SimpleTemporaryObjectKind, BTE, MTE) {}
public:
static bool classof(const ConstructionContext *CC) {
return CC->getKind() == SimpleTemporaryObjectKind;
}
};
/// Represents a temporary object that is constructed for the sole purpose
/// of being immediately copied by an elidable copy/move constructor.
/// For example, T t = T(123); includes a temporary T(123) that is immediately
/// copied to variable t. In such cases the elidable copy can (but not
/// necessarily should) be omitted ("elided") according to the rules of the
/// language; the constructor would then construct variable t directly.
/// This construction context contains information of the elidable constructor
/// and its respective construction context.
class ElidedTemporaryObjectConstructionContext
: public TemporaryObjectConstructionContext {
const CXXConstructExpr *ElidedCE;
const ConstructionContext *ElidedCC;
friend class ConstructionContext; // Allows to create<>() itself.
explicit ElidedTemporaryObjectConstructionContext(
const CXXBindTemporaryExpr *BTE, const MaterializeTemporaryExpr *MTE,
const CXXConstructExpr *ElidedCE, const ConstructionContext *ElidedCC)
: TemporaryObjectConstructionContext(
ConstructionContext::ElidedTemporaryObjectKind, BTE, MTE),
ElidedCE(ElidedCE), ElidedCC(ElidedCC) {
// Elided constructor and its context should be either both specified
// or both unspecified. In the former case, the constructor must be
// elidable.
assert(ElidedCE && ElidedCE->isElidable() && ElidedCC);
}
public:
const CXXConstructExpr *getConstructorAfterElision() const {
return ElidedCE;
}
const ConstructionContext *getConstructionContextAfterElision() const {
return ElidedCC;
}
static bool classof(const ConstructionContext *CC) {
return CC->getKind() == ElidedTemporaryObjectKind;
}
};
class ReturnedValueConstructionContext : public ConstructionContext {
const ReturnStmt *RS;
protected:
explicit ReturnedValueConstructionContext(ConstructionContext::Kind K,
const ReturnStmt *RS)
: ConstructionContext(K), RS(RS) {
assert(classof(this));
assert(RS);
}
public:
const ReturnStmt *getReturnStmt() const { return RS; }
static bool classof(const ConstructionContext *CC) {
return CC->getKind() >= RETURNED_VALUE_BEGIN &&
CC->getKind() <= RETURNED_VALUE_END;
}
};
/// Represents a temporary object that is being immediately returned from a
/// function by value, eg. return t; or return T(123);. In this case there is
/// always going to be a constructor at the return site. However, the usual
/// temporary-related bureaucracy (CXXBindTemporaryExpr,
/// MaterializeTemporaryExpr) is normally located in the caller function's AST.
class SimpleReturnedValueConstructionContext
: public ReturnedValueConstructionContext {
friend class ConstructionContext; // Allows to create<>() itself.
explicit SimpleReturnedValueConstructionContext(const ReturnStmt *RS)
: ReturnedValueConstructionContext(
ConstructionContext::SimpleReturnedValueKind, RS) {}
public:
static bool classof(const ConstructionContext *CC) {
return CC->getKind() == SimpleReturnedValueKind;
}
};
/// Represents a temporary object that is being immediately returned from a
/// function by value, eg. return t; or return T(123); in C++17.
/// In C++17 there is not going to be an elidable copy constructor at the
/// return site. However, the usual temporary-related bureaucracy (CXXBindTemporaryExpr,
/// MaterializeTemporaryExpr) is normally located in the caller function's AST.
/// Note that if the object has trivial destructor, then this code is
/// indistinguishable from a simple returned value constructor on the AST level;
/// in this case we provide a simple returned value construction context.
class CXX17ElidedCopyReturnedValueConstructionContext
: public ReturnedValueConstructionContext {
const CXXBindTemporaryExpr *BTE;
friend class ConstructionContext; // Allows to create<>() itself.
explicit CXX17ElidedCopyReturnedValueConstructionContext(
const ReturnStmt *RS, const CXXBindTemporaryExpr *BTE)
: ReturnedValueConstructionContext(
ConstructionContext::CXX17ElidedCopyReturnedValueKind, RS),
BTE(BTE) {
assert(BTE);
}
public:
const CXXBindTemporaryExpr *getCXXBindTemporaryExpr() const { return BTE; }
static bool classof(const ConstructionContext *CC) {
return CC->getKind() == CXX17ElidedCopyReturnedValueKind;
}
};
class ArgumentConstructionContext : public ConstructionContext {
// The call of which the context is an argument.
const Expr *CE;
// Which argument we're constructing. Note that when numbering between
// arguments and parameters is inconsistent (eg., operator calls),
// this is the index of the argument, not of the parameter.
unsigned Index;
// Whether the object needs to be destroyed.
const CXXBindTemporaryExpr *BTE;
friend class ConstructionContext; // Allows to create<>() itself.
explicit ArgumentConstructionContext(const Expr *CE, unsigned Index,
const CXXBindTemporaryExpr *BTE)
: ConstructionContext(ArgumentKind), CE(CE),
Index(Index), BTE(BTE) {
assert(isa<CallExpr>(CE) || isa<CXXConstructExpr>(CE) ||
isa<ObjCMessageExpr>(CE));
// BTE is optional.
}
public:
const Expr *getCallLikeExpr() const { return CE; }
unsigned getIndex() const { return Index; }
const CXXBindTemporaryExpr *getCXXBindTemporaryExpr() const { return BTE; }
static bool classof(const ConstructionContext *CC) {
return CC->getKind() == ArgumentKind;
}
};
class LambdaCaptureConstructionContext : public ConstructionContext {
// The lambda of which the initializer we capture.
const LambdaExpr *LE;
// Index of the captured element in the captured list.
unsigned Index;
friend class ConstructionContext; // Allows to create<>() itself.
explicit LambdaCaptureConstructionContext(const LambdaExpr *LE,
unsigned Index)
: ConstructionContext(LambdaCaptureKind), LE(LE), Index(Index) {}
public:
const LambdaExpr *getLambdaExpr() const { return LE; }
unsigned getIndex() const { return Index; }
const Expr *getInitializer() const {
return *(LE->capture_init_begin() + Index);
}
const FieldDecl *getFieldDecl() const {
auto It = LE->getLambdaClass()->field_begin();
std::advance(It, Index);
return *It;
}
const ArrayInitLoopExpr *getArrayInitLoop() const override {
return dyn_cast_or_null<ArrayInitLoopExpr>(getInitializer());
}
static bool classof(const ConstructionContext *CC) {
return CC->getKind() == LambdaCaptureKind;
}
};
} // end namespace clang
#endif // LLVM_CLANG_ANALYSIS_CONSTRUCTIONCONTEXT_H
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