lib/Option/OptTable.cpp

   1 //===- OptTable.cpp - Option Table Implementation -------------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include "llvm/ADT/STLExtras.h"
  11 #include "llvm/ADT/StringRef.h"
  12 #include "llvm/ADT/StringSet.h"
  13 #include "llvm/Option/Arg.h"
  14 #include "llvm/Option/ArgList.h"
  15 #include "llvm/Option/Option.h"
  16 #include "llvm/Option/OptSpecifier.h"
  17 #include "llvm/Option/OptTable.h"
  18 #include "llvm/Support/Compiler.h"
  19 #include "llvm/Support/ErrorHandling.h"
  20 #include "llvm/Support/raw_ostream.h"
  21 #include <algorithm>
  22 #include <cassert>
  23 #include <cctype>
  24 #include <cstring>
  25 #include <map>
  26 #include <string>
  27 #include <utility>
  28 #include <vector>
  29
  30 using namespace llvm;
  31 using namespace llvm::opt;
  32
  33 namespace llvm {
  34 namespace opt {
  35
  36 // Ordering on Info. The ordering is *almost* case-insensitive lexicographic,
  37 // with an exception. '\0' comes at the end of the alphabet instead of the
  38 // beginning (thus options precede any other options which prefix them).
  39 static int StrCmpOptionNameIgnoreCase(const char *A, const char *B) {
  40   const char *X = A, *Y = B;
  41   char a = tolower(*A), b = tolower(*B);
  42   while (a == b) {
  43     if (a == '\0')
  44       return 0;
  45
  46     a = tolower(*++X);
  47     b = tolower(*++Y);
  48   }
  49
  50   if (a == '\0') // A is a prefix of B.
  51     return 1;
  52   if (b == '\0') // B is a prefix of A.
  53     return -1;
  54
  55   // Otherwise lexicographic.
  56   return (a < b) ? -1 : 1;
  57 }
  58
  59 #ifndef NDEBUG
  60 static int StrCmpOptionName(const char *A, const char *B) {
  61   if (int N = StrCmpOptionNameIgnoreCase(A, B))
  62     return N;
  63   return strcmp(A, B);
  64 }
  65
  66 static inline bool operator<(const OptTable::Info &A, const OptTable::Info &B) {
  67   if (&A == &B)
  68     return false;
  69
  70   if (int N = StrCmpOptionName(A.Name, B.Name))
  71     return N < 0;
  72
  73   for (const char * const *APre = A.Prefixes,
  74                   * const *BPre = B.Prefixes;
  75                           *APre != nullptr && *BPre != nullptr; ++APre, ++BPre){
  76     if (int N = StrCmpOptionName(*APre, *BPre))
  77       return N < 0;
  78   }
  79
  80   // Names are the same, check that classes are in order; exactly one
  81   // should be joined, and it should succeed the other.
  82   assert(((A.Kind == Option::JoinedClass) ^ (B.Kind == Option::JoinedClass)) &&
  83          "Unexpected classes for options with same name.");
  84   return B.Kind == Option::JoinedClass;
  85 }
  86 #endif
  87
  88 // Support lower_bound between info and an option name.
  89 static inline bool operator<(const OptTable::Info &I, const char *Name) {
  90   return StrCmpOptionNameIgnoreCase(I.Name, Name) < 0;
  91 }
  92
  93 } // end namespace opt
  94 } // end namespace llvm
  95
  96 OptSpecifier::OptSpecifier(const Option *Opt) : ID(Opt->getID()) {}
  97
  98 OptTable::OptTable(ArrayRef<Info> OptionInfos, bool IgnoreCase)
  99     : OptionInfos(OptionInfos), IgnoreCase(IgnoreCase) {
 100   // Explicitly zero initialize the error to work around a bug in array
 101   // value-initialization on MinGW with gcc 4.3.5.
 102
 103   // Find start of normal options.
 104   for (unsigned i = 0, e = getNumOptions(); i != e; ++i) {
 105     unsigned Kind = getInfo(i + 1).Kind;
 106     if (Kind == Option::InputClass) {
 107       assert(!TheInputOptionID && "Cannot have multiple input options!");
 108       TheInputOptionID = getInfo(i + 1).ID;
 109     } else if (Kind == Option::UnknownClass) {
 110       assert(!TheUnknownOptionID && "Cannot have multiple unknown options!");
 111       TheUnknownOptionID = getInfo(i + 1).ID;
 112     } else if (Kind != Option::GroupClass) {
 113       FirstSearchableIndex = i;
 114       break;
 115     }
 116   }
 117   assert(FirstSearchableIndex != 0 && "No searchable options?");
 118
 119 #ifndef NDEBUG
 120   // Check that everything after the first searchable option is a
 121   // regular option class.
 122   for (unsigned i = FirstSearchableIndex, e = getNumOptions(); i != e; ++i) {
 123     Option::OptionClass Kind = (Option::OptionClass) getInfo(i + 1).Kind;
 124     assert((Kind != Option::InputClass && Kind != Option::UnknownClass &&
 125             Kind != Option::GroupClass) &&
 126            "Special options should be defined first!");
 127   }
 128
 129   // Check that options are in order.
 130   for (unsigned i = FirstSearchableIndex + 1, e = getNumOptions(); i != e; ++i){
 131     if (!(getInfo(i) < getInfo(i + 1))) {
 132       getOption(i).dump();
 133       getOption(i + 1).dump();
 134       llvm_unreachable("Options are not in order!");
 135     }
 136   }
 137 #endif
 138
 139   // Build prefixes.
 140   for (unsigned i = FirstSearchableIndex + 1, e = getNumOptions() + 1;
 141                 i != e; ++i) {
 142     if (const char *const *P = getInfo(i).Prefixes) {
 143       for (; *P != nullptr; ++P) {
 144         PrefixesUnion.insert(*P);
 145       }
 146     }
 147   }
 148
 149   // Build prefix chars.
 150   for (StringSet<>::const_iterator I = PrefixesUnion.begin(),
 151                                    E = PrefixesUnion.end(); I != E; ++I) {
 152     StringRef Prefix = I->getKey();
 153     for (StringRef::const_iterator C = Prefix.begin(), CE = Prefix.end();
 154                                    C != CE; ++C)
 155       if (!is_contained(PrefixChars, *C))
 156         PrefixChars.push_back(*C);
 157   }
 158 }
 159
 160 OptTable::~OptTable() = default;
 161
 162 const Option OptTable::getOption(OptSpecifier Opt) const {
 163   unsigned id = Opt.getID();
 164   if (id == 0)
 165     return Option(nullptr, nullptr);
 166   assert((unsigned) (id - 1) < getNumOptions() && "Invalid ID.");
 167   return Option(&getInfo(id), this);
 168 }
 169
 170 static bool isInput(const StringSet<> &Prefixes, StringRef Arg) {
 171   if (Arg == "-")
 172     return true;
 173   for (StringSet<>::const_iterator I = Prefixes.begin(),
 174                                    E = Prefixes.end(); I != E; ++I)
 175     if (Arg.startswith(I->getKey()))
 176       return false;
 177   return true;
 178 }
 179
 180 /// \returns Matched size. 0 means no match.
 181 static unsigned matchOption(const OptTable::Info *I, StringRef Str,
 182                             bool IgnoreCase) {
 183   for (const char * const *Pre = I->Prefixes; *Pre != nullptr; ++Pre) {
 184     StringRef Prefix(*Pre);
 185     if (Str.startswith(Prefix)) {
 186       StringRef Rest = Str.substr(Prefix.size());
 187       bool Matched = IgnoreCase
 188           ? Rest.startswith_lower(I->Name)
 189           : Rest.startswith(I->Name);
 190       if (Matched)
 191         return Prefix.size() + StringRef(I->Name).size();
 192     }
 193   }
 194   return 0;
 195 }
 196
 197 // Returns true if one of the Prefixes + In.Names matches Option
 198 static bool optionMatches(const OptTable::Info &In, StringRef Option) {
 199   if (In.Prefixes)
 200     for (size_t I = 0; In.Prefixes[I]; I++)
 201       if (Option == std::string(In.Prefixes[I]) + In.Name)
 202         return true;
 203   return false;
 204 }
 205
 206 // This function is for flag value completion.
 207 // Eg. When "-stdlib=" and "l" was passed to this function, it will return
 208 // appropiriate values for stdlib, which starts with l.
 209 std::vector<std::string>
 210 OptTable::suggestValueCompletions(StringRef Option, StringRef Arg) const {
 211   // Search all options and return possible values.
 212   for (size_t I = FirstSearchableIndex, E = OptionInfos.size(); I < E; I++) {
 213     const Info &In = OptionInfos[I];
 214     if (!In.Values || !optionMatches(In, Option))
 215       continue;
 216
 217     SmallVector<StringRef, 8> Candidates;
 218     StringRef(In.Values).split(Candidates, ",", -1, false);
 219
 220     std::vector<std::string> Result;
 221     for (StringRef Val : Candidates)
 222       if (Val.startswith(Arg))
 223         Result.push_back(Val);
 224     return Result;
 225   }
 226   return {};
 227 }
 228
 229 std::vector<std::string>
 230 OptTable::findByPrefix(StringRef Cur, unsigned short DisableFlags) const {
 231   std::vector<std::string> Ret;
 232   for (size_t I = FirstSearchableIndex, E = OptionInfos.size(); I < E; I++) {
 233     const Info &In = OptionInfos[I];
 234     if (!In.Prefixes || (!In.HelpText && !In.GroupID))
 235       continue;
 236     if (In.Flags & DisableFlags)
 237       continue;
 238
 239     for (int I = 0; In.Prefixes[I]; I++) {
 240       std::string S = std::string(In.Prefixes[I]) + std::string(In.Name) + "\t";
 241       if (In.HelpText)
 242         S += In.HelpText;
 243       if (StringRef(S).startswith(Cur))
 244         Ret.push_back(S);
 245     }
 246   }
 247   return Ret;
 248 }
 249
 250 bool OptTable::addValues(const char *Option, const char *Values) {
 251   for (size_t I = FirstSearchableIndex, E = OptionInfos.size(); I < E; I++) {
 252     Info &In = OptionInfos[I];
 253     if (optionMatches(In, Option)) {
 254       In.Values = Values;
 255       return true;
 256     }
 257   }
 258   return false;
 259 }
 260
 261 Arg *OptTable::ParseOneArg(const ArgList &Args, unsigned &Index,
 262                            unsigned FlagsToInclude,
 263                            unsigned FlagsToExclude) const {
 264   unsigned Prev = Index;
 265   const char *Str = Args.getArgString(Index);
 266
 267   // Anything that doesn't start with PrefixesUnion is an input, as is '-'
 268   // itself.
 269   if (isInput(PrefixesUnion, Str))
 270     return new Arg(getOption(TheInputOptionID), Str, Index++, Str);
 271
 272   const Info *Start = OptionInfos.data() + FirstSearchableIndex;
 273   const Info *End = OptionInfos.data() + OptionInfos.size();
 274   StringRef Name = StringRef(Str).ltrim(PrefixChars);
 275
 276   // Search for the first next option which could be a prefix.
 277   Start = std::lower_bound(Start, End, Name.data());
 278
 279   // Options are stored in sorted order, with '\0' at the end of the
 280   // alphabet. Since the only options which can accept a string must
 281   // prefix it, we iteratively search for the next option which could
 282   // be a prefix.
 283   //
 284   // FIXME: This is searching much more than necessary, but I am
 285   // blanking on the simplest way to make it fast. We can solve this
 286   // problem when we move to TableGen.
 287   for (; Start != End; ++Start) {
 288     unsigned ArgSize = 0;
 289     // Scan for first option which is a proper prefix.
 290     for (; Start != End; ++Start)
 291       if ((ArgSize = matchOption(Start, Str, IgnoreCase)))
 292         break;
 293     if (Start == End)
 294       break;
 295
 296     Option Opt(Start, this);
 297
 298     if (FlagsToInclude && !Opt.hasFlag(FlagsToInclude))
 299       continue;
 300     if (Opt.hasFlag(FlagsToExclude))
 301       continue;
 302
 303     // See if this option matches.
 304     if (Arg *A = Opt.accept(Args, Index, ArgSize))
 305       return A;
 306
 307     // Otherwise, see if this argument was missing values.
 308     if (Prev != Index)
 309       return nullptr;
 310   }
 311
 312   // If we failed to find an option and this arg started with /, then it's
 313   // probably an input path.
 314   if (Str[0] == '/')
 315     return new Arg(getOption(TheInputOptionID), Str, Index++, Str);
 316
 317   return new Arg(getOption(TheUnknownOptionID), Str, Index++, Str);
 318 }
 319
 320 InputArgList OptTable::ParseArgs(ArrayRef<const char *> ArgArr,
 321                                  unsigned &MissingArgIndex,
 322                                  unsigned &MissingArgCount,
 323                                  unsigned FlagsToInclude,
 324                                  unsigned FlagsToExclude) const {
 325   InputArgList Args(ArgArr.begin(), ArgArr.end());
 326
 327   // FIXME: Handle '@' args (or at least error on them).
 328
 329   MissingArgIndex = MissingArgCount = 0;
 330   unsigned Index = 0, End = ArgArr.size();
 331   while (Index < End) {
 332     // Ingore nullptrs, they are response file's EOL markers
 333     if (Args.getArgString(Index) == nullptr) {
 334       ++Index;
 335       continue;
 336     }
 337     // Ignore empty arguments (other things may still take them as arguments).
 338     StringRef Str = Args.getArgString(Index);
 339     if (Str == "") {
 340       ++Index;
 341       continue;
 342     }
 343
 344     unsigned Prev = Index;
 345     Arg *A = ParseOneArg(Args, Index, FlagsToInclude, FlagsToExclude);
 346     assert(Index > Prev && "Parser failed to consume argument.");
 347
 348     // Check for missing argument error.
 349     if (!A) {
 350       assert(Index >= End && "Unexpected parser error.");
 351       assert(Index - Prev - 1 && "No missing arguments!");
 352       MissingArgIndex = Prev;
 353       MissingArgCount = Index - Prev - 1;
 354       break;
 355     }
 356
 357     Args.append(A);
 358   }
 359
 360   return Args;
 361 }
 362
 363 static std::string getOptionHelpName(const OptTable &Opts, OptSpecifier Id) {
 364   const Option O = Opts.getOption(Id);
 365   std::string Name = O.getPrefixedName();
 366
 367   // Add metavar, if used.
 368   switch (O.getKind()) {
 369   case Option::GroupClass: case Option::InputClass: case Option::UnknownClass:
 370     llvm_unreachable("Invalid option with help text.");
 371
 372   case Option::MultiArgClass:
 373     if (const char *MetaVarName = Opts.getOptionMetaVar(Id)) {
 374       // For MultiArgs, metavar is full list of all argument names.
 375       Name += ' ';
 376       Name += MetaVarName;
 377     }
 378     else {
 379       // For MultiArgs<N>, if metavar not supplied, print <value> N times.
 380       for (unsigned i=0, e=O.getNumArgs(); i< e; ++i) {
 381         Name += " <value>";
 382       }
 383     }
 384     break;
 385
 386   case Option::FlagClass:
 387     break;
 388
 389   case Option::ValuesClass:
 390     break;
 391
 392   case Option::SeparateClass: case Option::JoinedOrSeparateClass:
 393   case Option::RemainingArgsClass: case Option::RemainingArgsJoinedClass:
 394     Name += ' ';
 395     LLVM_FALLTHROUGH;
 396   case Option::JoinedClass: case Option::CommaJoinedClass:
 397   case Option::JoinedAndSeparateClass:
 398     if (const char *MetaVarName = Opts.getOptionMetaVar(Id))
 399       Name += MetaVarName;
 400     else
 401       Name += "<value>";
 402     break;
 403   }
 404
 405   return Name;
 406 }
 407
 408 namespace {
 409 struct OptionInfo {
 410   std::string Name;
 411   StringRef HelpText;
 412 };
 413 } // namespace
 414
 415 static void PrintHelpOptionList(raw_ostream &OS, StringRef Title,
 416                                 std::vector<OptionInfo> &OptionHelp) {
 417   OS << Title << ":\n";
 418
 419   // Find the maximum option length.
 420   unsigned OptionFieldWidth = 0;
 421   for (unsigned i = 0, e = OptionHelp.size(); i != e; ++i) {
 422     // Limit the amount of padding we are willing to give up for alignment.
 423     unsigned Length = OptionHelp[i].Name.size();
 424     if (Length <= 23)
 425       OptionFieldWidth = std::max(OptionFieldWidth, Length);
 426   }
 427
 428   const unsigned InitialPad = 2;
 429   for (unsigned i = 0, e = OptionHelp.size(); i != e; ++i) {
 430     const std::string &Option = OptionHelp[i].Name;
 431     int Pad = OptionFieldWidth - int(Option.size());
 432     OS.indent(InitialPad) << Option;
 433
 434     // Break on long option names.
 435     if (Pad < 0) {
 436       OS << "\n";
 437       Pad = OptionFieldWidth + InitialPad;
 438     }
 439     OS.indent(Pad + 1) << OptionHelp[i].HelpText << '\n';
 440   }
 441 }
 442
 443 static const char *getOptionHelpGroup(const OptTable &Opts, OptSpecifier Id) {
 444   unsigned GroupID = Opts.getOptionGroupID(Id);
 445
 446   // If not in a group, return the default help group.
 447   if (!GroupID)
 448     return "OPTIONS";
 449
 450   // Abuse the help text of the option groups to store the "help group"
 451   // name.
 452   //
 453   // FIXME: Split out option groups.
 454   if (const char *GroupHelp = Opts.getOptionHelpText(GroupID))
 455     return GroupHelp;
 456
 457   // Otherwise keep looking.
 458   return getOptionHelpGroup(Opts, GroupID);
 459 }
 460
 461 void OptTable::PrintHelp(raw_ostream &OS, const char *Name, const char *Title,
 462                          bool ShowHidden, bool ShowAllAliases) const {
 463   PrintHelp(OS, Name, Title, /*Include*/ 0, /*Exclude*/
 464             (ShowHidden ? 0 : HelpHidden), ShowAllAliases);
 465 }
 466
 467 void OptTable::PrintHelp(raw_ostream &OS, const char *Name, const char *Title,
 468                          unsigned FlagsToInclude, unsigned FlagsToExclude,
 469                          bool ShowAllAliases) const {
 470   OS << "OVERVIEW: " << Title << "\n";
 471   OS << '\n';
 472   OS << "USAGE: " << Name << " [options] <inputs>\n";
 473   OS << '\n';
 474
 475   // Render help text into a map of group-name to a list of (option, help)
 476   // pairs.
 477   using helpmap_ty = std::map<std::string, std::vector<OptionInfo>>;
 478   helpmap_ty GroupedOptionHelp;
 479
 480   for (unsigned i = 0, e = getNumOptions(); i != e; ++i) {
 481     unsigned Id = i + 1;
 482
 483     // FIXME: Split out option groups.
 484     if (getOptionKind(Id) == Option::GroupClass)
 485       continue;
 486
 487     unsigned Flags = getInfo(Id).Flags;
 488     if (FlagsToInclude && !(Flags & FlagsToInclude))
 489       continue;
 490     if (Flags & FlagsToExclude)
 491       continue;
 492
 493     // If an alias doesn't have a help text, show a help text for the aliased
 494     // option instead.
 495     const char *HelpText = getOptionHelpText(Id);
 496     if (!HelpText && ShowAllAliases) {
 497       const Option Alias = getOption(Id).getAlias();
 498       if (Alias.isValid())
 499         HelpText = getOptionHelpText(Alias.getID());
 500     }
 501
 502     if (HelpText) {
 503       const char *HelpGroup = getOptionHelpGroup(*this, Id);
 504       const std::string &OptName = getOptionHelpName(*this, Id);
 505       GroupedOptionHelp[HelpGroup].push_back({OptName, HelpText});
 506     }
 507   }
 508
 509   for (helpmap_ty::iterator it = GroupedOptionHelp .begin(),
 510          ie = GroupedOptionHelp.end(); it != ie; ++it) {
 511     if (it != GroupedOptionHelp .begin())
 512       OS << "\n";
 513     PrintHelpOptionList(OS, it->first, it->second);
 514   }
 515
 516   OS.flush();
 517 }