1 //===- ClangOptionDocEmitter.cpp - Documentation for command line flags ---===//
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
7 // FIXME: Once this has stabilized, consider moving it to LLVM.
9 //===----------------------------------------------------------------------===//
11 #include "TableGenBackends.h"
12 #include "llvm/TableGen/Error.h"
13 #include "llvm/ADT/STLExtras.h"
14 #include "llvm/ADT/SmallString.h"
15 #include "llvm/ADT/StringSwitch.h"
16 #include "llvm/ADT/Twine.h"
17 #include "llvm/TableGen/Record.h"
18 #include "llvm/TableGen/TableGenBackend.h"
26 struct DocumentedOption {
28 std::vector<Record*> Aliases;
30 struct DocumentedGroup;
31 struct Documentation {
32 std::vector<DocumentedGroup> Groups;
33 std::vector<DocumentedOption> Options;
35 struct DocumentedGroup : Documentation {
39 // Reorganize the records into a suitable form for emitting documentation.
40 Documentation extractDocumentation(RecordKeeper &Records) {
43 // Build the tree of groups. The root in the tree is the fake option group
44 // (Record*)nullptr, which contains all top-level groups and options.
45 std::map<Record*, std::vector<Record*> > OptionsInGroup;
46 std::map<Record*, std::vector<Record*> > GroupsInGroup;
47 std::map<Record*, std::vector<Record*> > Aliases;
49 std::map<std::string, Record*> OptionsByName;
50 for (Record *R : Records.getAllDerivedDefinitions("Option"))
51 OptionsByName[R->getValueAsString("Name")] = R;
53 auto Flatten = [](Record *R) {
54 return R->getValue("DocFlatten") && R->getValueAsBit("DocFlatten");
57 auto SkipFlattened = [&](Record *R) -> Record* {
58 while (R && Flatten(R)) {
59 auto *G = dyn_cast<DefInit>(R->getValueInit("Group"));
67 for (Record *R : Records.getAllDerivedDefinitions("OptionGroup")) {
71 Record *Group = nullptr;
72 if (auto *G = dyn_cast<DefInit>(R->getValueInit("Group")))
73 Group = SkipFlattened(G->getDef());
74 GroupsInGroup[Group].push_back(R);
77 for (Record *R : Records.getAllDerivedDefinitions("Option")) {
78 if (auto *A = dyn_cast<DefInit>(R->getValueInit("Alias"))) {
79 Aliases[A->getDef()].push_back(R);
83 // Pretend no-X and Xno-Y options are aliases of X and XY.
84 std::string Name = R->getValueAsString("Name");
85 if (Name.size() >= 4) {
86 if (Name.substr(0, 3) == "no-" && OptionsByName[Name.substr(3)]) {
87 Aliases[OptionsByName[Name.substr(3)]].push_back(R);
90 if (Name.substr(1, 3) == "no-" && OptionsByName[Name[0] + Name.substr(4)]) {
91 Aliases[OptionsByName[Name[0] + Name.substr(4)]].push_back(R);
96 Record *Group = nullptr;
97 if (auto *G = dyn_cast<DefInit>(R->getValueInit("Group")))
98 Group = SkipFlattened(G->getDef());
99 OptionsInGroup[Group].push_back(R);
102 auto CompareByName = [](Record *A, Record *B) {
103 return A->getValueAsString("Name") < B->getValueAsString("Name");
106 auto CompareByLocation = [](Record *A, Record *B) {
107 return A->getLoc()[0].getPointer() < B->getLoc()[0].getPointer();
110 auto DocumentationForOption = [&](Record *R) -> DocumentedOption {
111 auto &A = Aliases[R];
112 llvm::sort(A, CompareByName);
113 return {R, std::move(A)};
116 std::function<Documentation(Record *)> DocumentationForGroup =
117 [&](Record *R) -> Documentation {
120 auto &Groups = GroupsInGroup[R];
121 llvm::sort(Groups, CompareByLocation);
122 for (Record *G : Groups) {
123 D.Groups.emplace_back();
124 D.Groups.back().Group = G;
125 Documentation &Base = D.Groups.back();
126 Base = DocumentationForGroup(G);
129 auto &Options = OptionsInGroup[R];
130 llvm::sort(Options, CompareByName);
131 for (Record *O : Options)
132 D.Options.push_back(DocumentationForOption(O));
137 return DocumentationForGroup(nullptr);
140 // Get the first and successive separators to use for an OptionKind.
141 std::pair<StringRef,StringRef> getSeparatorsForKind(const Record *OptionKind) {
142 return StringSwitch<std::pair<StringRef, StringRef>>(OptionKind->getName())
143 .Cases("KIND_JOINED", "KIND_JOINED_OR_SEPARATE",
144 "KIND_JOINED_AND_SEPARATE",
145 "KIND_REMAINING_ARGS_JOINED", {"", " "})
146 .Case("KIND_COMMAJOINED", {"", ","})
147 .Default({" ", " "});
150 const unsigned UnlimitedArgs = unsigned(-1);
152 // Get the number of arguments expected for an option, or -1 if any number of
153 // arguments are accepted.
154 unsigned getNumArgsForKind(Record *OptionKind, const Record *Option) {
155 return StringSwitch<unsigned>(OptionKind->getName())
156 .Cases("KIND_JOINED", "KIND_JOINED_OR_SEPARATE", "KIND_SEPARATE", 1)
157 .Cases("KIND_REMAINING_ARGS", "KIND_REMAINING_ARGS_JOINED",
158 "KIND_COMMAJOINED", UnlimitedArgs)
159 .Case("KIND_JOINED_AND_SEPARATE", 2)
160 .Case("KIND_MULTIARG", Option->getValueAsInt("NumArgs"))
164 bool hasFlag(const Record *OptionOrGroup, StringRef OptionFlag) {
165 for (const Record *Flag : OptionOrGroup->getValueAsListOfDefs("Flags"))
166 if (Flag->getName() == OptionFlag)
171 bool isExcluded(const Record *OptionOrGroup, const Record *DocInfo) {
172 // FIXME: Provide a flag to specify the set of exclusions.
173 for (StringRef Exclusion : DocInfo->getValueAsListOfStrings("ExcludedFlags"))
174 if (hasFlag(OptionOrGroup, Exclusion))
179 std::string escapeRST(StringRef Str) {
182 if (StringRef("`*|_[]\\").count(K))
189 StringRef getSphinxOptionID(StringRef OptionName) {
190 for (auto I = OptionName.begin(), E = OptionName.end(); I != E; ++I)
191 if (!isalnum(*I) && *I != '-')
192 return OptionName.substr(0, I - OptionName.begin());
196 bool canSphinxCopeWithOption(const Record *Option) {
197 // HACK: Work arond sphinx's inability to cope with punctuation-only options
198 // such as /? by suppressing them from the option list.
199 for (char C : Option->getValueAsString("Name"))
205 void emitHeading(int Depth, std::string Heading, raw_ostream &OS) {
206 assert(Depth < 8 && "groups nested too deeply");
207 OS << Heading << '\n'
208 << std::string(Heading.size(), "=~-_'+<>"[Depth]) << "\n";
211 /// Get the value of field \p Primary, if possible. If \p Primary does not
212 /// exist, get the value of \p Fallback and escape it for rST emission.
213 std::string getRSTStringWithTextFallback(const Record *R, StringRef Primary,
214 StringRef Fallback) {
215 for (auto Field : {Primary, Fallback}) {
216 if (auto *V = R->getValue(Field)) {
218 if (auto *SV = dyn_cast_or_null<StringInit>(V->getValue()))
219 Value = SV->getValue();
220 else if (auto *CV = dyn_cast_or_null<CodeInit>(V->getValue()))
221 Value = CV->getValue();
223 return Field == Primary ? Value.str() : escapeRST(Value);
229 void emitOptionWithArgs(StringRef Prefix, const Record *Option,
230 ArrayRef<StringRef> Args, raw_ostream &OS) {
231 OS << Prefix << escapeRST(Option->getValueAsString("Name"));
233 std::pair<StringRef, StringRef> Separators =
234 getSeparatorsForKind(Option->getValueAsDef("Kind"));
236 StringRef Separator = Separators.first;
237 for (auto Arg : Args) {
238 OS << Separator << escapeRST(Arg);
239 Separator = Separators.second;
243 void emitOptionName(StringRef Prefix, const Record *Option, raw_ostream &OS) {
244 // Find the arguments to list after the option.
245 unsigned NumArgs = getNumArgsForKind(Option->getValueAsDef("Kind"), Option);
246 bool HasMetaVarName = !Option->isValueUnset("MetaVarName");
248 std::vector<std::string> Args;
250 Args.push_back(Option->getValueAsString("MetaVarName"));
251 else if (NumArgs == 1)
252 Args.push_back("<arg>");
254 // Fill up arguments if this option didn't provide a meta var name or it
255 // supports an unlimited number of arguments. We can't see how many arguments
256 // already are in a meta var name, so assume it has right number. This is
257 // needed for JoinedAndSeparate options so that there arent't too many
259 if (!HasMetaVarName || NumArgs == UnlimitedArgs) {
260 while (Args.size() < NumArgs) {
261 Args.push_back(("<arg" + Twine(Args.size() + 1) + ">").str());
262 // Use '--args <arg1> <arg2>...' if any number of args are allowed.
263 if (Args.size() == 2 && NumArgs == UnlimitedArgs) {
264 Args.back() += "...";
270 emitOptionWithArgs(Prefix, Option, std::vector<StringRef>(Args.begin(), Args.end()), OS);
272 auto AliasArgs = Option->getValueAsListOfStrings("AliasArgs");
273 if (!AliasArgs.empty()) {
274 Record *Alias = Option->getValueAsDef("Alias");
275 OS << " (equivalent to ";
277 Alias->getValueAsListOfStrings("Prefixes").front(), Alias,
283 bool emitOptionNames(const Record *Option, raw_ostream &OS, bool EmittedAny) {
284 for (auto &Prefix : Option->getValueAsListOfStrings("Prefixes")) {
287 emitOptionName(Prefix, Option, OS);
293 template <typename Fn>
294 void forEachOptionName(const DocumentedOption &Option, const Record *DocInfo,
298 for (auto *Alias : Option.Aliases)
299 if (!isExcluded(Alias, DocInfo) && canSphinxCopeWithOption(Option.Option))
303 void emitOption(const DocumentedOption &Option, const Record *DocInfo,
305 if (isExcluded(Option.Option, DocInfo))
307 if (Option.Option->getValueAsDef("Kind")->getName() == "KIND_UNKNOWN" ||
308 Option.Option->getValueAsDef("Kind")->getName() == "KIND_INPUT")
310 if (!canSphinxCopeWithOption(Option.Option))
313 // HACK: Emit a different program name with each option to work around
314 // sphinx's inability to cope with options that differ only by punctuation
315 // (eg -ObjC vs -ObjC++, -G vs -G=).
316 std::vector<std::string> SphinxOptionIDs;
317 forEachOptionName(Option, DocInfo, [&](const Record *Option) {
318 for (auto &Prefix : Option->getValueAsListOfStrings("Prefixes"))
319 SphinxOptionIDs.push_back(
320 getSphinxOptionID((Prefix + Option->getValueAsString("Name")).str()));
322 assert(!SphinxOptionIDs.empty() && "no flags for option");
323 static std::map<std::string, int> NextSuffix;
324 int SphinxWorkaroundSuffix = NextSuffix[*std::max_element(
325 SphinxOptionIDs.begin(), SphinxOptionIDs.end(),
326 [&](const std::string &A, const std::string &B) {
327 return NextSuffix[A] < NextSuffix[B];
329 for (auto &S : SphinxOptionIDs)
330 NextSuffix[S] = SphinxWorkaroundSuffix + 1;
331 if (SphinxWorkaroundSuffix)
332 OS << ".. program:: " << DocInfo->getValueAsString("Program")
333 << SphinxWorkaroundSuffix << "\n";
335 // Emit the names of the option.
336 OS << ".. option:: ";
337 bool EmittedAny = false;
338 forEachOptionName(Option, DocInfo, [&](const Record *Option) {
339 EmittedAny = emitOptionNames(Option, OS, EmittedAny);
341 if (SphinxWorkaroundSuffix)
342 OS << "\n.. program:: " << DocInfo->getValueAsString("Program");
345 // Emit the description, if we have one.
346 std::string Description =
347 getRSTStringWithTextFallback(Option.Option, "DocBrief", "HelpText");
348 if (!Description.empty())
349 OS << Description << "\n\n";
352 void emitDocumentation(int Depth, const Documentation &Doc,
353 const Record *DocInfo, raw_ostream &OS);
355 void emitGroup(int Depth, const DocumentedGroup &Group, const Record *DocInfo,
357 if (isExcluded(Group.Group, DocInfo))
361 getRSTStringWithTextFallback(Group.Group, "DocName", "Name"), OS);
363 // Emit the description, if we have one.
364 std::string Description =
365 getRSTStringWithTextFallback(Group.Group, "DocBrief", "HelpText");
366 if (!Description.empty())
367 OS << Description << "\n\n";
369 // Emit contained options and groups.
370 emitDocumentation(Depth + 1, Group, DocInfo, OS);
373 void emitDocumentation(int Depth, const Documentation &Doc,
374 const Record *DocInfo, raw_ostream &OS) {
375 for (auto &O : Doc.Options)
376 emitOption(O, DocInfo, OS);
377 for (auto &G : Doc.Groups)
378 emitGroup(Depth, G, DocInfo, OS);
383 void clang::EmitClangOptDocs(RecordKeeper &Records, raw_ostream &OS) {
384 const Record *DocInfo = Records.getDef("GlobalDocumentation");
386 PrintFatalError("The GlobalDocumentation top-level definition is missing, "
387 "no documentation will be generated.");
390 OS << DocInfo->getValueAsString("Intro") << "\n";
391 OS << ".. program:: " << DocInfo->getValueAsString("Program") << "\n";
393 emitDocumentation(0, extractDocumentation(Records), DocInfo, OS);