1//===--- EnterExpressionEvaluationContext.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#ifndef LLVM_CLANG_SEMA_ENTEREXPRESSIONEVALUATIONCONTEXT_H
10#define LLVM_CLANG_SEMA_ENTEREXPRESSIONEVALUATIONCONTEXT_H
11
12#include "clang/Sema/Sema.h"
13
14namespace clang {
15
16class Decl;
17
18/// RAII object that enters a new expression evaluation context.
19class EnterExpressionEvaluationContext {
20 Sema &Actions;
21 bool Entered = true;
22
23public:
24 EnterExpressionEvaluationContext(
25 Sema &Actions, Sema::ExpressionEvaluationContext NewContext,
26 Decl *LambdaContextDecl = nullptr,
27 Sema::ExpressionEvaluationContextRecord::ExpressionKind ExprContext =
28 Sema::ExpressionEvaluationContextRecord::EK_Other,
29 bool ShouldEnter = true)
30 : Actions(Actions), Entered(ShouldEnter) {
31 if (Entered)
32 Actions.PushExpressionEvaluationContext(NewContext, LambdaContextDecl,
33 Type: ExprContext);
34 }
35 EnterExpressionEvaluationContext(
36 Sema &Actions, Sema::ExpressionEvaluationContext NewContext,
37 Sema::ReuseLambdaContextDecl_t,
38 Sema::ExpressionEvaluationContextRecord::ExpressionKind ExprContext =
39 Sema::ExpressionEvaluationContextRecord::EK_Other)
40 : Actions(Actions) {
41 Actions.PushExpressionEvaluationContext(
42 NewContext, Sema::ReuseLambdaContextDecl, Type: ExprContext);
43 }
44
45 enum InitListTag { InitList };
46 EnterExpressionEvaluationContext(Sema &Actions, InitListTag,
47 bool ShouldEnter = true)
48 : Actions(Actions), Entered(false) {
49 // In C++11 onwards, narrowing checks are performed on the contents of
50 // braced-init-lists, even when they occur within unevaluated operands.
51 // Therefore we still need to instantiate constexpr functions used in such
52 // a context.
53 if (ShouldEnter && Actions.isUnevaluatedContext() &&
54 Actions.getLangOpts().CPlusPlus11) {
55 Actions.PushExpressionEvaluationContext(
56 NewContext: Sema::ExpressionEvaluationContext::UnevaluatedList);
57 Entered = true;
58 }
59 }
60
61 ~EnterExpressionEvaluationContext() {
62 if (Entered)
63 Actions.PopExpressionEvaluationContext();
64 }
65};
66
67} // namespace clang
68
69#endif
70

source code of clang/include/clang/Sema/EnterExpressionEvaluationContext.h