1 //===- VersionTuple.h - Version Number Handling -----------------*- 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 /// Defines the llvm::VersionTuple class, which represents a version in
11 /// the form major[.minor[.subminor]].
12 ///
13 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_SUPPORT_VERSIONTUPLE_H
15 #define LLVM_SUPPORT_VERSIONTUPLE_H
16 
17 #include "llvm/ADT/DenseMapInfo.h"
18 #include "llvm/ADT/Hashing.h"
19 #include "llvm/Support/Endian.h"
20 #include <optional>
21 #include <string>
22 #include <tuple>
23 
24 namespace llvm {
25 template <typename HasherT, support::endianness Endianness>
26 class HashBuilderImpl;
27 class raw_ostream;
28 class StringRef;
29 
30 /// Represents a version number in the form major[.minor[.subminor[.build]]].
31 class VersionTuple {
32   unsigned Major : 32;
33 
34   unsigned Minor : 31;
35   unsigned HasMinor : 1;
36 
37   unsigned Subminor : 31;
38   unsigned HasSubminor : 1;
39 
40   unsigned Build : 31;
41   unsigned HasBuild : 1;
42 
43 public:
44   constexpr VersionTuple()
45       : Major(0), Minor(0), HasMinor(false), Subminor(0), HasSubminor(false),
46         Build(0), HasBuild(false) {}
47 
48   explicit constexpr VersionTuple(unsigned Major)
49       : Major(Major), Minor(0), HasMinor(false), Subminor(0),
50         HasSubminor(false), Build(0), HasBuild(false) {}
51 
52   explicit constexpr VersionTuple(unsigned Major, unsigned Minor)
53       : Major(Major), Minor(Minor), HasMinor(true), Subminor(0),
54         HasSubminor(false), Build(0), HasBuild(false) {}
55 
56   explicit constexpr VersionTuple(unsigned Major, unsigned Minor,
57                                   unsigned Subminor)
58       : Major(Major), Minor(Minor), HasMinor(true), Subminor(Subminor),
59         HasSubminor(true), Build(0), HasBuild(false) {}
60 
61   explicit constexpr VersionTuple(unsigned Major, unsigned Minor,
62                                   unsigned Subminor, unsigned Build)
63       : Major(Major), Minor(Minor), HasMinor(true), Subminor(Subminor),
64         HasSubminor(true), Build(Build), HasBuild(true) {}
65 
66   /// Determine whether this version information is empty
67   /// (e.g., all version components are zero).
68   bool empty() const {
69     return Major == 0 && Minor == 0 && Subminor == 0 && Build == 0;
70   }
71 
72   /// Retrieve the major version number.
73   unsigned getMajor() const { return Major; }
74 
75   /// Retrieve the minor version number, if provided.
76   std::optional<unsigned> getMinor() const {
77     if (!HasMinor)
78       return std::nullopt;
79     return Minor;
80   }
81 
82   /// Retrieve the subminor version number, if provided.
83   std::optional<unsigned> getSubminor() const {
84     if (!HasSubminor)
85       return std::nullopt;
86     return Subminor;
87   }
88 
89   /// Retrieve the build version number, if provided.
90   std::optional<unsigned> getBuild() const {
91     if (!HasBuild)
92       return std::nullopt;
93     return Build;
94   }
95 
96   /// Return a version tuple that contains only the first 3 version components.
97   VersionTuple withoutBuild() const {
98     if (HasBuild)
99       return VersionTuple(Major, Minor, Subminor);
100     return *this;
101   }
102 
103   /// Return a version tuple that contains a different major version but
104   /// everything else is the same.
105   VersionTuple withMajorReplaced(unsigned NewMajor) const {
106     return VersionTuple(NewMajor, Minor, Subminor, Build);
107   }
108 
109   /// Return a version tuple that contains only components that are non-zero.
110   VersionTuple normalize() const {
111     VersionTuple Result = *this;
112     if (Result.Build == 0) {
113       Result.HasBuild = false;
114       if (Result.Subminor == 0) {
115         Result.HasSubminor = false;
116         if (Result.Minor == 0)
117           Result.HasMinor = false;
118       }
119     }
120     return Result;
121   }
122 
123   /// Determine if two version numbers are equivalent. If not
124   /// provided, minor and subminor version numbers are considered to be zero.
125   friend bool operator==(const VersionTuple &X, const VersionTuple &Y) {
126     return X.Major == Y.Major && X.Minor == Y.Minor &&
127            X.Subminor == Y.Subminor && X.Build == Y.Build;
128   }
129 
130   /// Determine if two version numbers are not equivalent.
131   ///
132   /// If not provided, minor and subminor version numbers are considered to be
133   /// zero.
134   friend bool operator!=(const VersionTuple &X, const VersionTuple &Y) {
135     return !(X == Y);
136   }
137 
138   /// Determine whether one version number precedes another.
139   ///
140   /// If not provided, minor and subminor version numbers are considered to be
141   /// zero.
142   friend bool operator<(const VersionTuple &X, const VersionTuple &Y) {
143     return std::tie(X.Major, X.Minor, X.Subminor, X.Build) <
144            std::tie(Y.Major, Y.Minor, Y.Subminor, Y.Build);
145   }
146 
147   /// Determine whether one version number follows another.
148   ///
149   /// If not provided, minor and subminor version numbers are considered to be
150   /// zero.
151   friend bool operator>(const VersionTuple &X, const VersionTuple &Y) {
152     return Y < X;
153   }
154 
155   /// Determine whether one version number precedes or is
156   /// equivalent to another.
157   ///
158   /// If not provided, minor and subminor version numbers are considered to be
159   /// zero.
160   friend bool operator<=(const VersionTuple &X, const VersionTuple &Y) {
161     return !(Y < X);
162   }
163 
164   /// Determine whether one version number follows or is
165   /// equivalent to another.
166   ///
167   /// If not provided, minor and subminor version numbers are considered to be
168   /// zero.
169   friend bool operator>=(const VersionTuple &X, const VersionTuple &Y) {
170     return !(X < Y);
171   }
172 
173   friend hash_code hash_value(const VersionTuple &VT) {
174     return hash_combine(VT.Major, VT.Minor, VT.Subminor, VT.Build);
175   }
176 
177   template <typename HasherT, llvm::support::endianness Endianness>
178   friend void addHash(HashBuilderImpl<HasherT, Endianness> &HBuilder,
179                       const VersionTuple &VT) {
180     HBuilder.add(VT.Major, VT.Minor, VT.Subminor, VT.Build);
181   }
182 
183   /// Retrieve a string representation of the version number.
184   std::string getAsString() const;
185 
186   /// Try to parse the given string as a version number.
187   /// \returns \c true if the string does not match the regular expression
188   ///   [0-9]+(\.[0-9]+){0,3}
189   bool tryParse(StringRef string);
190 };
191 
192 /// Print a version number.
193 raw_ostream &operator<<(raw_ostream &Out, const VersionTuple &V);
194 
195 // Provide DenseMapInfo for version tuples.
196 template <> struct DenseMapInfo<VersionTuple> {
197   static inline VersionTuple getEmptyKey() { return VersionTuple(0x7FFFFFFF); }
198   static inline VersionTuple getTombstoneKey() {
199     return VersionTuple(0x7FFFFFFE);
200   }
201   static unsigned getHashValue(const VersionTuple &Value) {
202     unsigned Result = Value.getMajor();
203     if (auto Minor = Value.getMinor())
204       Result = detail::combineHashValue(Result, *Minor);
205     if (auto Subminor = Value.getSubminor())
206       Result = detail::combineHashValue(Result, *Subminor);
207     if (auto Build = Value.getBuild())
208       Result = detail::combineHashValue(Result, *Build);
209 
210     return Result;
211   }
212 
213   static bool isEqual(const VersionTuple &LHS, const VersionTuple &RHS) {
214     return LHS == RHS;
215   }
216 };
217 
218 } // end namespace llvm
219 #endif // LLVM_SUPPORT_VERSIONTUPLE_H
220