1//===-------------- TypeOrdering.h - Total ordering for types ---*- 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/// \file
10/// Allows QualTypes to be sorted and hence used in maps and sets.
11///
12/// Defines clang::QualTypeOrdering, a total ordering on clang::QualType,
13/// and hence enables QualType values to be sorted and to be used in
14/// std::maps, std::sets, llvm::DenseMaps, and llvm::DenseSets.
15///
16//===----------------------------------------------------------------------===//
17
18#ifndef LLVM_CLANG_AST_TYPEORDERING_H
19#define LLVM_CLANG_AST_TYPEORDERING_H
20
21#include "clang/AST/CanonicalType.h"
22#include "clang/AST/Type.h"
23#include <functional>
24
25namespace clang {
26
27/// Function object that provides a total ordering on QualType values.
28struct QualTypeOrdering {
29  bool operator()(QualType T1, QualType T2) const {
30    return std::less<void*>()(T1.getAsOpaquePtr(), T2.getAsOpaquePtr());
31  }
32};
33
34}
35
36namespace llvm {
37
38  template<> struct DenseMapInfo<clang::QualType> {
39    static inline clang::QualType getEmptyKey() { return clang::QualType(); }
40
41    static inline clang::QualType getTombstoneKey() {
42      using clang::QualType;
43      return QualType::getFromOpaquePtr(reinterpret_cast<clang::Type *>(-1));
44    }
45
46    static unsigned getHashValue(clang::QualType Val) {
47      return (unsigned)((uintptr_t)Val.getAsOpaquePtr()) ^
48            ((unsigned)((uintptr_t)Val.getAsOpaquePtr() >> 9));
49    }
50
51    static bool isEqual(clang::QualType LHS, clang::QualType RHS) {
52      return LHS == RHS;
53    }
54  };
55
56  template<> struct DenseMapInfo<clang::CanQualType> {
57    static inline clang::CanQualType getEmptyKey() {
58      return clang::CanQualType();
59    }
60
61    static inline clang::CanQualType getTombstoneKey() {
62      using clang::CanQualType;
63      return CanQualType::getFromOpaquePtr(reinterpret_cast<clang::Type *>(-1));
64    }
65
66    static unsigned getHashValue(clang::CanQualType Val) {
67      return (unsigned)((uintptr_t)Val.getAsOpaquePtr()) ^
68      ((unsigned)((uintptr_t)Val.getAsOpaquePtr() >> 9));
69    }
70
71    static bool isEqual(clang::CanQualType LHS, clang::CanQualType RHS) {
72      return LHS == RHS;
73    }
74  };
75}
76
77#endif
78