llvm-for-llvmta/tools/clang/utils/TableGen/ClangOptionDocEmitter.cpp

393 lines
13 KiB
C++
Raw Normal View History

2022-04-25 13:02:35 +02:00
//===- ClangOptionDocEmitter.cpp - Documentation for command line flags ---===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
// FIXME: Once this has stabilized, consider moving it to LLVM.
//
//===----------------------------------------------------------------------===//
#include "TableGenBackends.h"
#include "llvm/TableGen/Error.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/ADT/Twine.h"
#include "llvm/TableGen/Record.h"
#include "llvm/TableGen/TableGenBackend.h"
#include <cctype>
#include <cstring>
#include <map>
using namespace llvm;
namespace {
struct DocumentedOption {
Record *Option;
std::vector<Record*> Aliases;
};
struct DocumentedGroup;
struct Documentation {
std::vector<DocumentedGroup> Groups;
std::vector<DocumentedOption> Options;
};
struct DocumentedGroup : Documentation {
Record *Group;
};
// Reorganize the records into a suitable form for emitting documentation.
Documentation extractDocumentation(RecordKeeper &Records) {
Documentation Result;
// Build the tree of groups. The root in the tree is the fake option group
// (Record*)nullptr, which contains all top-level groups and options.
std::map<Record*, std::vector<Record*> > OptionsInGroup;
std::map<Record*, std::vector<Record*> > GroupsInGroup;
std::map<Record*, std::vector<Record*> > Aliases;
std::map<std::string, Record*> OptionsByName;
for (Record *R : Records.getAllDerivedDefinitions("Option"))
OptionsByName[std::string(R->getValueAsString("Name"))] = R;
auto Flatten = [](Record *R) {
return R->getValue("DocFlatten") && R->getValueAsBit("DocFlatten");
};
auto SkipFlattened = [&](Record *R) -> Record* {
while (R && Flatten(R)) {
auto *G = dyn_cast<DefInit>(R->getValueInit("Group"));
if (!G)
return nullptr;
R = G->getDef();
}
return R;
};
for (Record *R : Records.getAllDerivedDefinitions("OptionGroup")) {
if (Flatten(R))
continue;
Record *Group = nullptr;
if (auto *G = dyn_cast<DefInit>(R->getValueInit("Group")))
Group = SkipFlattened(G->getDef());
GroupsInGroup[Group].push_back(R);
}
for (Record *R : Records.getAllDerivedDefinitions("Option")) {
if (auto *A = dyn_cast<DefInit>(R->getValueInit("Alias"))) {
Aliases[A->getDef()].push_back(R);
continue;
}
// Pretend no-X and Xno-Y options are aliases of X and XY.
std::string Name = std::string(R->getValueAsString("Name"));
if (Name.size() >= 4) {
if (Name.substr(0, 3) == "no-" && OptionsByName[Name.substr(3)]) {
Aliases[OptionsByName[Name.substr(3)]].push_back(R);
continue;
}
if (Name.substr(1, 3) == "no-" && OptionsByName[Name[0] + Name.substr(4)]) {
Aliases[OptionsByName[Name[0] + Name.substr(4)]].push_back(R);
continue;
}
}
Record *Group = nullptr;
if (auto *G = dyn_cast<DefInit>(R->getValueInit("Group")))
Group = SkipFlattened(G->getDef());
OptionsInGroup[Group].push_back(R);
}
auto CompareByName = [](Record *A, Record *B) {
return A->getValueAsString("Name") < B->getValueAsString("Name");
};
auto CompareByLocation = [](Record *A, Record *B) {
return A->getLoc()[0].getPointer() < B->getLoc()[0].getPointer();
};
auto DocumentationForOption = [&](Record *R) -> DocumentedOption {
auto &A = Aliases[R];
llvm::sort(A, CompareByName);
return {R, std::move(A)};
};
std::function<Documentation(Record *)> DocumentationForGroup =
[&](Record *R) -> Documentation {
Documentation D;
auto &Groups = GroupsInGroup[R];
llvm::sort(Groups, CompareByLocation);
for (Record *G : Groups) {
D.Groups.emplace_back();
D.Groups.back().Group = G;
Documentation &Base = D.Groups.back();
Base = DocumentationForGroup(G);
}
auto &Options = OptionsInGroup[R];
llvm::sort(Options, CompareByName);
for (Record *O : Options)
D.Options.push_back(DocumentationForOption(O));
return D;
};
return DocumentationForGroup(nullptr);
}
// Get the first and successive separators to use for an OptionKind.
std::pair<StringRef,StringRef> getSeparatorsForKind(const Record *OptionKind) {
return StringSwitch<std::pair<StringRef, StringRef>>(OptionKind->getName())
.Cases("KIND_JOINED", "KIND_JOINED_OR_SEPARATE",
"KIND_JOINED_AND_SEPARATE",
"KIND_REMAINING_ARGS_JOINED", {"", " "})
.Case("KIND_COMMAJOINED", {"", ","})
.Default({" ", " "});
}
const unsigned UnlimitedArgs = unsigned(-1);
// Get the number of arguments expected for an option, or -1 if any number of
// arguments are accepted.
unsigned getNumArgsForKind(Record *OptionKind, const Record *Option) {
return StringSwitch<unsigned>(OptionKind->getName())
.Cases("KIND_JOINED", "KIND_JOINED_OR_SEPARATE", "KIND_SEPARATE", 1)
.Cases("KIND_REMAINING_ARGS", "KIND_REMAINING_ARGS_JOINED",
"KIND_COMMAJOINED", UnlimitedArgs)
.Case("KIND_JOINED_AND_SEPARATE", 2)
.Case("KIND_MULTIARG", Option->getValueAsInt("NumArgs"))
.Default(0);
}
bool hasFlag(const Record *OptionOrGroup, StringRef OptionFlag) {
for (const Record *Flag : OptionOrGroup->getValueAsListOfDefs("Flags"))
if (Flag->getName() == OptionFlag)
return true;
return false;
}
bool isExcluded(const Record *OptionOrGroup, const Record *DocInfo) {
// FIXME: Provide a flag to specify the set of exclusions.
for (StringRef Exclusion : DocInfo->getValueAsListOfStrings("ExcludedFlags"))
if (hasFlag(OptionOrGroup, Exclusion))
return true;
return false;
}
std::string escapeRST(StringRef Str) {
std::string Out;
for (auto K : Str) {
if (StringRef("`*|_[]\\").count(K))
Out.push_back('\\');
Out.push_back(K);
}
return Out;
}
StringRef getSphinxOptionID(StringRef OptionName) {
for (auto I = OptionName.begin(), E = OptionName.end(); I != E; ++I)
if (!isalnum(*I) && *I != '-')
return OptionName.substr(0, I - OptionName.begin());
return OptionName;
}
bool canSphinxCopeWithOption(const Record *Option) {
// HACK: Work arond sphinx's inability to cope with punctuation-only options
// such as /? by suppressing them from the option list.
for (char C : Option->getValueAsString("Name"))
if (isalnum(C))
return true;
return false;
}
void emitHeading(int Depth, std::string Heading, raw_ostream &OS) {
assert(Depth < 8 && "groups nested too deeply");
OS << Heading << '\n'
<< std::string(Heading.size(), "=~-_'+<>"[Depth]) << "\n";
}
/// Get the value of field \p Primary, if possible. If \p Primary does not
/// exist, get the value of \p Fallback and escape it for rST emission.
std::string getRSTStringWithTextFallback(const Record *R, StringRef Primary,
StringRef Fallback) {
for (auto Field : {Primary, Fallback}) {
if (auto *V = R->getValue(Field)) {
StringRef Value;
if (auto *SV = dyn_cast_or_null<StringInit>(V->getValue()))
Value = SV->getValue();
if (!Value.empty())
return Field == Primary ? Value.str() : escapeRST(Value);
}
}
return std::string(StringRef());
}
void emitOptionWithArgs(StringRef Prefix, const Record *Option,
ArrayRef<StringRef> Args, raw_ostream &OS) {
OS << Prefix << escapeRST(Option->getValueAsString("Name"));
std::pair<StringRef, StringRef> Separators =
getSeparatorsForKind(Option->getValueAsDef("Kind"));
StringRef Separator = Separators.first;
for (auto Arg : Args) {
OS << Separator << escapeRST(Arg);
Separator = Separators.second;
}
}
void emitOptionName(StringRef Prefix, const Record *Option, raw_ostream &OS) {
// Find the arguments to list after the option.
unsigned NumArgs = getNumArgsForKind(Option->getValueAsDef("Kind"), Option);
bool HasMetaVarName = !Option->isValueUnset("MetaVarName");
std::vector<std::string> Args;
if (HasMetaVarName)
Args.push_back(std::string(Option->getValueAsString("MetaVarName")));
else if (NumArgs == 1)
Args.push_back("<arg>");
// Fill up arguments if this option didn't provide a meta var name or it
// supports an unlimited number of arguments. We can't see how many arguments
// already are in a meta var name, so assume it has right number. This is
// needed for JoinedAndSeparate options so that there arent't too many
// arguments.
if (!HasMetaVarName || NumArgs == UnlimitedArgs) {
while (Args.size() < NumArgs) {
Args.push_back(("<arg" + Twine(Args.size() + 1) + ">").str());
// Use '--args <arg1> <arg2>...' if any number of args are allowed.
if (Args.size() == 2 && NumArgs == UnlimitedArgs) {
Args.back() += "...";
break;
}
}
}
emitOptionWithArgs(Prefix, Option, std::vector<StringRef>(Args.begin(), Args.end()), OS);
auto AliasArgs = Option->getValueAsListOfStrings("AliasArgs");
if (!AliasArgs.empty()) {
Record *Alias = Option->getValueAsDef("Alias");
OS << " (equivalent to ";
emitOptionWithArgs(
Alias->getValueAsListOfStrings("Prefixes").front(), Alias,
AliasArgs, OS);
OS << ")";
}
}
bool emitOptionNames(const Record *Option, raw_ostream &OS, bool EmittedAny) {
for (auto &Prefix : Option->getValueAsListOfStrings("Prefixes")) {
if (EmittedAny)
OS << ", ";
emitOptionName(Prefix, Option, OS);
EmittedAny = true;
}
return EmittedAny;
}
template <typename Fn>
void forEachOptionName(const DocumentedOption &Option, const Record *DocInfo,
Fn F) {
F(Option.Option);
for (auto *Alias : Option.Aliases)
if (!isExcluded(Alias, DocInfo) && canSphinxCopeWithOption(Option.Option))
F(Alias);
}
void emitOption(const DocumentedOption &Option, const Record *DocInfo,
raw_ostream &OS) {
if (isExcluded(Option.Option, DocInfo))
return;
if (Option.Option->getValueAsDef("Kind")->getName() == "KIND_UNKNOWN" ||
Option.Option->getValueAsDef("Kind")->getName() == "KIND_INPUT")
return;
if (!canSphinxCopeWithOption(Option.Option))
return;
// HACK: Emit a different program name with each option to work around
// sphinx's inability to cope with options that differ only by punctuation
// (eg -ObjC vs -ObjC++, -G vs -G=).
std::vector<std::string> SphinxOptionIDs;
forEachOptionName(Option, DocInfo, [&](const Record *Option) {
for (auto &Prefix : Option->getValueAsListOfStrings("Prefixes"))
SphinxOptionIDs.push_back(std::string(getSphinxOptionID(
(Prefix + Option->getValueAsString("Name")).str())));
});
assert(!SphinxOptionIDs.empty() && "no flags for option");
static std::map<std::string, int> NextSuffix;
int SphinxWorkaroundSuffix = NextSuffix[*std::max_element(
SphinxOptionIDs.begin(), SphinxOptionIDs.end(),
[&](const std::string &A, const std::string &B) {
return NextSuffix[A] < NextSuffix[B];
})];
for (auto &S : SphinxOptionIDs)
NextSuffix[S] = SphinxWorkaroundSuffix + 1;
if (SphinxWorkaroundSuffix)
OS << ".. program:: " << DocInfo->getValueAsString("Program")
<< SphinxWorkaroundSuffix << "\n";
// Emit the names of the option.
OS << ".. option:: ";
bool EmittedAny = false;
forEachOptionName(Option, DocInfo, [&](const Record *Option) {
EmittedAny = emitOptionNames(Option, OS, EmittedAny);
});
if (SphinxWorkaroundSuffix)
OS << "\n.. program:: " << DocInfo->getValueAsString("Program");
OS << "\n\n";
// Emit the description, if we have one.
std::string Description =
getRSTStringWithTextFallback(Option.Option, "DocBrief", "HelpText");
if (!Description.empty())
OS << Description << "\n\n";
}
void emitDocumentation(int Depth, const Documentation &Doc,
const Record *DocInfo, raw_ostream &OS);
void emitGroup(int Depth, const DocumentedGroup &Group, const Record *DocInfo,
raw_ostream &OS) {
if (isExcluded(Group.Group, DocInfo))
return;
emitHeading(Depth,
getRSTStringWithTextFallback(Group.Group, "DocName", "Name"), OS);
// Emit the description, if we have one.
std::string Description =
getRSTStringWithTextFallback(Group.Group, "DocBrief", "HelpText");
if (!Description.empty())
OS << Description << "\n\n";
// Emit contained options and groups.
emitDocumentation(Depth + 1, Group, DocInfo, OS);
}
void emitDocumentation(int Depth, const Documentation &Doc,
const Record *DocInfo, raw_ostream &OS) {
for (auto &O : Doc.Options)
emitOption(O, DocInfo, OS);
for (auto &G : Doc.Groups)
emitGroup(Depth, G, DocInfo, OS);
}
} // namespace
void clang::EmitClangOptDocs(RecordKeeper &Records, raw_ostream &OS) {
const Record *DocInfo = Records.getDef("GlobalDocumentation");
if (!DocInfo) {
PrintFatalError("The GlobalDocumentation top-level definition is missing, "
"no documentation will be generated.");
return;
}
OS << DocInfo->getValueAsString("Intro") << "\n";
OS << ".. program:: " << DocInfo->getValueAsString("Program") << "\n";
emitDocumentation(0, extractDocumentation(Records), DocInfo, OS);
}