1//===-- UnresolvedSet.h - Unresolved sets of declarations  ------*- 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//  This file defines the WeakInfo class, which is used to store
10//  information about the target of a #pragma weak directive.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_CLANG_SEMA_WEAK_H
15#define LLVM_CLANG_SEMA_WEAK_H
16
17#include "clang/Basic/SourceLocation.h"
18#include "llvm/ADT/DenseMapInfo.h"
19
20namespace clang {
21
22class IdentifierInfo;
23
24/// Captures information about a \#pragma weak directive.
25class WeakInfo {
26  const IdentifierInfo *alias = nullptr; // alias (optional)
27  SourceLocation loc;                    // for diagnostics
28public:
29  WeakInfo() = default;
30  WeakInfo(const IdentifierInfo *Alias, SourceLocation Loc)
31      : alias(Alias), loc(Loc) {}
32  inline const IdentifierInfo *getAlias() const { return alias; }
33  inline SourceLocation getLocation() const { return loc; }
34  bool operator==(WeakInfo RHS) const = delete;
35  bool operator!=(WeakInfo RHS) const = delete;
36
37  struct DenseMapInfoByAliasOnly
38      : private llvm::DenseMapInfo<const IdentifierInfo *> {
39    static inline WeakInfo getEmptyKey() {
40      return WeakInfo(DenseMapInfo::getEmptyKey(), SourceLocation());
41    }
42    static inline WeakInfo getTombstoneKey() {
43      return WeakInfo(DenseMapInfo::getTombstoneKey(), SourceLocation());
44    }
45    static unsigned getHashValue(const WeakInfo &W) {
46      return DenseMapInfo::getHashValue(W.getAlias());
47    }
48    static bool isEqual(const WeakInfo &LHS, const WeakInfo &RHS) {
49      return DenseMapInfo::isEqual(LHS.getAlias(), RHS.getAlias());
50    }
51  };
52};
53
54} // end namespace clang
55
56#endif // LLVM_CLANG_SEMA_WEAK_H
57