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(Ptr: 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(Ptr: 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

source code of clang/include/clang/AST/TypeOrdering.h