aboutsummaryrefslogtreecommitdiff
path: root/include/clang/AST/ExprCXX.h
diff options
context:
space:
mode:
Diffstat (limited to 'include/clang/AST/ExprCXX.h')
-rw-r--r--include/clang/AST/ExprCXX.h58
1 files changed, 58 insertions, 0 deletions
diff --git a/include/clang/AST/ExprCXX.h b/include/clang/AST/ExprCXX.h
index a970579737..1b1019e554 100644
--- a/include/clang/AST/ExprCXX.h
+++ b/include/clang/AST/ExprCXX.h
@@ -2987,6 +2987,64 @@ public:
// Iterators
child_range children() { return child_range(); }
};
+
+/// \brief Represents a prvalue temporary that written into memory so that
+/// a reference can bind to it.
+///
+/// Prvalue expressions are materialized when they need to have an address
+/// in memory for a reference to bind to. This happens when binding a
+/// reference to the result of a conversion, e.g.,
+///
+/// \code
+/// const int &r = 1.0;
+/// \endcode
+///
+/// Here, 1.0 is implicitly converted to an \c int. That resulting \c int is
+/// then materialized via a \c MaterializeTemporaryExpr, and the reference
+/// binds to the temporary. \c MaterializeTemporaryExprs are always glvalues
+/// (either an lvalue or an xvalue, depending on the kind of reference binding
+/// to it), maintaining the invariant that references always bind to glvalues.
+class MaterializeTemporaryExpr : public Expr {
+ /// \brief The temporary-generating expression whose value will be
+ /// materialized.
+ Stmt *Temporary;
+
+ friend class ASTStmtReader;
+ friend class ASTStmtWriter;
+
+public:
+ MaterializeTemporaryExpr(Expr *Temporary, bool BoundToLvalueReference)
+ : Expr(MaterializeTemporaryExprClass, Temporary->getType(),
+ BoundToLvalueReference? VK_LValue : VK_XValue, OK_Ordinary,
+ Temporary->isTypeDependent(), Temporary->isValueDependent(),
+ Temporary->containsUnexpandedParameterPack()),
+ Temporary(Temporary) { }
+
+ MaterializeTemporaryExpr(EmptyShell Empty)
+ : Expr(MaterializeTemporaryExprClass, Empty) { }
+
+ /// \brief Retrieve the temporary-generating subexpression whose value will
+ /// be materialized into a glvalue.
+ Expr *GetTemporaryExpr() const { return reinterpret_cast<Expr *>(Temporary); }
+
+ /// \brief Determine whether this materialized temporary is bound to an
+ /// lvalue reference; otherwise, it's bound to an rvalue reference.
+ bool BoundToLvalueReference() const {
+ return getValueKind() == VK_LValue;
+ }
+
+ SourceRange getSourceRange() const { return Temporary->getSourceRange(); }
+
+ static bool classof(const Stmt *T) {
+ return T->getStmtClass() == MaterializeTemporaryExprClass;
+ }
+ static bool classof(const MaterializeTemporaryExpr *) {
+ return true;
+ }
+
+ // Iterators
+ child_range children() { return child_range(&Temporary, &Temporary + 1); }
+};
} // end namespace clang