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