1//===- Multilib.cpp - Multilib Implementation -----------------------------===//
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#include "clang/Driver/Multilib.h"
10#include "clang/Basic/LLVM.h"
11#include "clang/Basic/Version.h"
12#include "llvm/ADT/DenseSet.h"
13#include "llvm/ADT/SmallString.h"
14#include "llvm/ADT/StringRef.h"
15#include "llvm/Support/Compiler.h"
16#include "llvm/Support/Error.h"
17#include "llvm/Support/ErrorHandling.h"
18#include "llvm/Support/Path.h"
19#include "llvm/Support/Regex.h"
20#include "llvm/Support/VersionTuple.h"
21#include "llvm/Support/YAMLParser.h"
22#include "llvm/Support/YAMLTraits.h"
23#include "llvm/Support/raw_ostream.h"
24#include <algorithm>
25#include <cassert>
26#include <string>
27
28using namespace clang;
29using namespace driver;
30using namespace llvm::sys;
31
32Multilib::Multilib(StringRef GCCSuffix, StringRef OSSuffix,
33 StringRef IncludeSuffix, const flags_list &Flags,
34 StringRef ExclusiveGroup)
35 : GCCSuffix(GCCSuffix), OSSuffix(OSSuffix), IncludeSuffix(IncludeSuffix),
36 Flags(Flags), ExclusiveGroup(ExclusiveGroup) {
37 assert(GCCSuffix.empty() ||
38 (StringRef(GCCSuffix).front() == '/' && GCCSuffix.size() > 1));
39 assert(OSSuffix.empty() ||
40 (StringRef(OSSuffix).front() == '/' && OSSuffix.size() > 1));
41 assert(IncludeSuffix.empty() ||
42 (StringRef(IncludeSuffix).front() == '/' && IncludeSuffix.size() > 1));
43}
44
45LLVM_DUMP_METHOD void Multilib::dump() const {
46 print(OS&: llvm::errs());
47}
48
49void Multilib::print(raw_ostream &OS) const {
50 if (GCCSuffix.empty())
51 OS << ".";
52 else {
53 OS << StringRef(GCCSuffix).drop_front();
54 }
55 OS << ";";
56 for (StringRef Flag : Flags) {
57 if (Flag.front() == '-')
58 OS << "@" << Flag.substr(Start: 1);
59 }
60}
61
62bool Multilib::operator==(const Multilib &Other) const {
63 // Check whether the flags sets match
64 // allowing for the match to be order invariant
65 llvm::StringSet<> MyFlags;
66 for (const auto &Flag : Flags)
67 MyFlags.insert(key: Flag);
68
69 for (const auto &Flag : Other.Flags)
70 if (!MyFlags.contains(key: Flag))
71 return false;
72
73 if (osSuffix() != Other.osSuffix())
74 return false;
75
76 if (gccSuffix() != Other.gccSuffix())
77 return false;
78
79 if (includeSuffix() != Other.includeSuffix())
80 return false;
81
82 return true;
83}
84
85raw_ostream &clang::driver::operator<<(raw_ostream &OS, const Multilib &M) {
86 M.print(OS);
87 return OS;
88}
89
90MultilibSet &MultilibSet::FilterOut(FilterCallback F) {
91 llvm::erase_if(C&: Multilibs, P: F);
92 return *this;
93}
94
95void MultilibSet::push_back(const Multilib &M) { Multilibs.push_back(x: M); }
96
97bool MultilibSet::select(const Multilib::flags_list &Flags,
98 llvm::SmallVectorImpl<Multilib> &Selected) const {
99 llvm::StringSet<> FlagSet(expandFlags(Flags));
100 Selected.clear();
101
102 // Decide which multilibs we're going to select at all.
103 llvm::DenseSet<StringRef> ExclusiveGroupsSelected;
104 for (const Multilib &M : llvm::reverse(C: Multilibs)) {
105 // If this multilib doesn't match all our flags, don't select it.
106 if (!llvm::all_of(Range: M.flags(), P: [&FlagSet](const std::string &F) {
107 return FlagSet.contains(key: F);
108 }))
109 continue;
110
111 const std::string &group = M.exclusiveGroup();
112 if (!group.empty()) {
113 // If this multilib has the same ExclusiveGroup as one we've already
114 // selected, skip it. We're iterating in reverse order, so the group
115 // member we've selected already is preferred.
116 //
117 // Otherwise, add the group name to the set of groups we've already
118 // selected a member of.
119 auto [It, Inserted] = ExclusiveGroupsSelected.insert(V: group);
120 if (!Inserted)
121 continue;
122 }
123
124 // Select this multilib.
125 Selected.push_back(Elt: M);
126 }
127
128 // We iterated in reverse order, so now put Selected back the right way
129 // round.
130 std::reverse(first: Selected.begin(), last: Selected.end());
131
132 return !Selected.empty();
133}
134
135llvm::StringSet<>
136MultilibSet::expandFlags(const Multilib::flags_list &InFlags) const {
137 llvm::StringSet<> Result;
138 for (const auto &F : InFlags)
139 Result.insert(key: F);
140 for (const FlagMatcher &M : FlagMatchers) {
141 std::string RegexString(M.Match);
142
143 // Make the regular expression match the whole string.
144 if (!StringRef(M.Match).starts_with(Prefix: "^"))
145 RegexString.insert(p: RegexString.begin(), c: '^');
146 if (!StringRef(M.Match).ends_with(Suffix: "$"))
147 RegexString.push_back(c: '$');
148
149 const llvm::Regex Regex(RegexString);
150 assert(Regex.isValid());
151 if (llvm::any_of(Range: InFlags,
152 P: [&Regex](StringRef F) { return Regex.match(String: F); })) {
153 Result.insert(begin: M.Flags.begin(), end: M.Flags.end());
154 }
155 }
156 return Result;
157}
158
159namespace {
160
161// When updating this also update MULTILIB_VERSION in MultilibTest.cpp
162static const VersionTuple MultilibVersionCurrent(1, 0);
163
164struct MultilibSerialization {
165 std::string Dir;
166 std::vector<std::string> Flags;
167 std::string Group;
168};
169
170enum class MultilibGroupType {
171 /*
172 * The only group type currently supported is 'Exclusive', which indicates a
173 * group of multilibs of which at most one may be selected.
174 */
175 Exclusive,
176
177 /*
178 * Future possibility: a second group type indicating a set of library
179 * directories that are mutually _dependent_ rather than mutually exclusive:
180 * if you include one you must include them all.
181 *
182 * It might also be useful to allow groups to be members of other groups, so
183 * that a mutually exclusive group could contain a mutually dependent set of
184 * library directories, or vice versa.
185 *
186 * These additional features would need changes in the implementation, but
187 * the YAML schema is set up so they can be added without requiring changes
188 * in existing users' multilib.yaml files.
189 */
190};
191
192struct MultilibGroupSerialization {
193 std::string Name;
194 MultilibGroupType Type;
195};
196
197struct MultilibSetSerialization {
198 llvm::VersionTuple MultilibVersion;
199 std::vector<MultilibGroupSerialization> Groups;
200 std::vector<MultilibSerialization> Multilibs;
201 std::vector<MultilibSet::FlagMatcher> FlagMatchers;
202};
203
204} // end anonymous namespace
205
206template <> struct llvm::yaml::MappingTraits<MultilibSerialization> {
207 static void mapping(llvm::yaml::IO &io, MultilibSerialization &V) {
208 io.mapRequired(Key: "Dir", Val&: V.Dir);
209 io.mapRequired(Key: "Flags", Val&: V.Flags);
210 io.mapOptional(Key: "Group", Val&: V.Group);
211 }
212 static std::string validate(IO &io, MultilibSerialization &V) {
213 if (StringRef(V.Dir).starts_with(Prefix: "/"))
214 return "paths must be relative but \"" + V.Dir + "\" starts with \"/\"";
215 return std::string{};
216 }
217};
218
219template <> struct llvm::yaml::ScalarEnumerationTraits<MultilibGroupType> {
220 static void enumeration(IO &io, MultilibGroupType &Val) {
221 io.enumCase(Val, Str: "Exclusive", ConstVal: MultilibGroupType::Exclusive);
222 }
223};
224
225template <> struct llvm::yaml::MappingTraits<MultilibGroupSerialization> {
226 static void mapping(llvm::yaml::IO &io, MultilibGroupSerialization &V) {
227 io.mapRequired(Key: "Name", Val&: V.Name);
228 io.mapRequired(Key: "Type", Val&: V.Type);
229 }
230};
231
232template <> struct llvm::yaml::MappingTraits<MultilibSet::FlagMatcher> {
233 static void mapping(llvm::yaml::IO &io, MultilibSet::FlagMatcher &M) {
234 io.mapRequired(Key: "Match", Val&: M.Match);
235 io.mapRequired(Key: "Flags", Val&: M.Flags);
236 }
237 static std::string validate(IO &io, MultilibSet::FlagMatcher &M) {
238 llvm::Regex Regex(M.Match);
239 std::string RegexError;
240 if (!Regex.isValid(Error&: RegexError))
241 return RegexError;
242 if (M.Flags.empty())
243 return "value required for 'Flags'";
244 return std::string{};
245 }
246};
247
248template <> struct llvm::yaml::MappingTraits<MultilibSetSerialization> {
249 static void mapping(llvm::yaml::IO &io, MultilibSetSerialization &M) {
250 io.mapRequired(Key: "MultilibVersion", Val&: M.MultilibVersion);
251 io.mapRequired(Key: "Variants", Val&: M.Multilibs);
252 io.mapOptional(Key: "Groups", Val&: M.Groups);
253 io.mapOptional(Key: "Mappings", Val&: M.FlagMatchers);
254 }
255 static std::string validate(IO &io, MultilibSetSerialization &M) {
256 if (M.MultilibVersion.empty())
257 return "missing required key 'MultilibVersion'";
258 if (M.MultilibVersion.getMajor() != MultilibVersionCurrent.getMajor())
259 return "multilib version " + M.MultilibVersion.getAsString() +
260 " is unsupported";
261 if (M.MultilibVersion.getMinor() > MultilibVersionCurrent.getMinor())
262 return "multilib version " + M.MultilibVersion.getAsString() +
263 " is unsupported";
264 for (const MultilibSerialization &Lib : M.Multilibs) {
265 if (!Lib.Group.empty()) {
266 bool Found = false;
267 for (const MultilibGroupSerialization &Group : M.Groups)
268 if (Group.Name == Lib.Group) {
269 Found = true;
270 break;
271 }
272 if (!Found)
273 return "multilib \"" + Lib.Dir +
274 "\" specifies undefined group name \"" + Lib.Group + "\"";
275 }
276 }
277 return std::string{};
278 }
279};
280
281LLVM_YAML_IS_SEQUENCE_VECTOR(MultilibSerialization)
282LLVM_YAML_IS_SEQUENCE_VECTOR(MultilibGroupSerialization)
283LLVM_YAML_IS_SEQUENCE_VECTOR(MultilibSet::FlagMatcher)
284
285llvm::ErrorOr<MultilibSet>
286MultilibSet::parseYaml(llvm::MemoryBufferRef Input,
287 llvm::SourceMgr::DiagHandlerTy DiagHandler,
288 void *DiagHandlerCtxt) {
289 MultilibSetSerialization MS;
290 llvm::yaml::Input YamlInput(Input, nullptr, DiagHandler, DiagHandlerCtxt);
291 YamlInput >> MS;
292 if (YamlInput.error())
293 return YamlInput.error();
294
295 multilib_list Multilibs;
296 Multilibs.reserve(n: MS.Multilibs.size());
297 for (const auto &M : MS.Multilibs) {
298 std::string Dir;
299 if (M.Dir != ".")
300 Dir = "/" + M.Dir;
301 // We transfer M.Group straight into the ExclusiveGroup parameter for the
302 // Multilib constructor. If we later support more than one type of group,
303 // we'll have to look up the group name in MS.Groups, check its type, and
304 // decide what to do here.
305 Multilibs.emplace_back(args&: Dir, args&: Dir, args&: Dir, args: M.Flags, args: M.Group);
306 }
307
308 return MultilibSet(std::move(Multilibs), std::move(MS.FlagMatchers));
309}
310
311LLVM_DUMP_METHOD void MultilibSet::dump() const {
312 print(OS&: llvm::errs());
313}
314
315void MultilibSet::print(raw_ostream &OS) const {
316 for (const auto &M : *this)
317 OS << M << "\n";
318}
319
320raw_ostream &clang::driver::operator<<(raw_ostream &OS, const MultilibSet &MS) {
321 MS.print(OS);
322 return OS;
323}
324

source code of clang/lib/Driver/Multilib.cpp