llvm/lib/Option/Option.cpp

   1 //===- Option.cpp - Abstract Driver Options -------------------------------===//
   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 "llvm/ADT/StringRef.h"
  10 #include "llvm/ADT/Twine.h"
  11 #include "llvm/Config/llvm-config.h"
  12 #include "llvm/Option/Arg.h"
  13 #include "llvm/Option/ArgList.h"
  14 #include "llvm/Option/Option.h"
  15 #include "llvm/Option/OptTable.h"
  16 #include "llvm/Support/Compiler.h"
  17 #include "llvm/Support/Debug.h"
  18 #include "llvm/Support/ErrorHandling.h"
  19 #include "llvm/Support/raw_ostream.h"
  20 #include <cassert>
  21 #include <cstring>
  22
  23 using namespace llvm;
  24 using namespace llvm::opt;
  25
  26 Option::Option(const OptTable::Info *info, const OptTable *owner)
  27   : Info(info), Owner(owner) {
  28   // Multi-level aliases are not supported. This just simplifies option
  29   // tracking, it is not an inherent limitation.
  30   assert((!Info || !getAlias().isValid() || !getAlias().getAlias().isValid()) &&
  31          "Multi-level aliases are not supported.");
  32
  33   if (Info && getAliasArgs()) {
  34     assert(getAlias().isValid() && "Only alias options can have alias args.");
  35     assert(getKind() == FlagClass && "Only Flag aliases can have alias args.");
  36     assert(getAlias().getKind() != FlagClass &&
  37            "Cannot provide alias args to a flag option.");
  38   }
  39 }
  40
  41 void Option::print(raw_ostream &O) const {
  42   O << "<";
  43   switch (getKind()) {
  44 #define P(N) case N: O << #N; break
  45     P(GroupClass);
  46     P(InputClass);
  47     P(UnknownClass);
  48     P(FlagClass);
  49     P(JoinedClass);
  50     P(ValuesClass);
  51     P(SeparateClass);
  52     P(CommaJoinedClass);
  53     P(MultiArgClass);
  54     P(JoinedOrSeparateClass);
  55     P(JoinedAndSeparateClass);
  56     P(RemainingArgsClass);
  57     P(RemainingArgsJoinedClass);
  58 #undef P
  59   }
  60
  61   if (Info->Prefixes) {
  62     O << " Prefixes:[";
  63     for (const char *const *Pre = Info->Prefixes; *Pre != nullptr; ++Pre) {
  64       O << '"' << *Pre << (*(Pre + 1) == nullptr ? "\"" : "\", ");
  65     }
  66     O << ']';
  67   }
  68
  69   O << " Name:\"" << getName() << '"';
  70
  71   const Option Group = getGroup();
  72   if (Group.isValid()) {
  73     O << " Group:";
  74     Group.print(O);
  75   }
  76
  77   const Option Alias = getAlias();
  78   if (Alias.isValid()) {
  79     O << " Alias:";
  80     Alias.print(O);
  81   }
  82
  83   if (getKind() == MultiArgClass)
  84     O << " NumArgs:" << getNumArgs();
  85
  86   O << ">\n";
  87 }
  88
  89 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
  90 LLVM_DUMP_METHOD void Option::dump() const { print(dbgs()); }
  91 #endif
  92
  93 bool Option::matches(OptSpecifier Opt) const {
  94   // Aliases are never considered in matching, look through them.
  95   const Option Alias = getAlias();
  96   if (Alias.isValid())
  97     return Alias.matches(Opt);
  98
  99   // Check exact match.
 100   if (getID() == Opt.getID())
 101     return true;
 102
 103   const Option Group = getGroup();
 104   if (Group.isValid())
 105     return Group.matches(Opt);
 106   return false;
 107 }
 108
 109 Arg *Option::acceptInternal(const ArgList &Args, StringRef Spelling,
 110                             unsigned &Index) const {
 111   size_t ArgSize = Spelling.size();
 112   switch (getKind()) {
 113   case FlagClass: {
 114     if (ArgSize != strlen(Args.getArgString(Index)))
 115       return nullptr;
 116     return new Arg(*this, Spelling, Index++);
 117   }
 118   case JoinedClass: {
 119     const char *Value = Args.getArgString(Index) + ArgSize;
 120     return new Arg(*this, Spelling, Index++, Value);
 121   }
 122   case CommaJoinedClass: {
 123     // Always matches.
 124     const char *Str = Args.getArgString(Index) + ArgSize;
 125     Arg *A = new Arg(*this, Spelling, Index++);
 126
 127     // Parse out the comma separated values.
 128     const char *Prev = Str;
 129     for (;; ++Str) {
 130       char c = *Str;
 131
 132       if (!c || c == ',') {
 133         if (Prev != Str) {
 134           char *Value = new char[Str - Prev + 1];
 135           memcpy(Value, Prev, Str - Prev);
 136           Value[Str - Prev] = '\0';
 137           A->getValues().push_back(Value);
 138         }
 139
 140         if (!c)
 141           break;
 142
 143         Prev = Str + 1;
 144       }
 145     }
 146     A->setOwnsValues(true);
 147
 148     return A;
 149   }
 150   case SeparateClass:
 151     // Matches iff this is an exact match.
 152     // FIXME: Avoid strlen.
 153     if (ArgSize != strlen(Args.getArgString(Index)))
 154       return nullptr;
 155
 156     Index += 2;
 157     if (Index > Args.getNumInputArgStrings() ||
 158         Args.getArgString(Index - 1) == nullptr)
 159       return nullptr;
 160
 161     return new Arg(*this, Spelling, Index - 2, Args.getArgString(Index - 1));
 162   case MultiArgClass: {
 163     // Matches iff this is an exact match.
 164     // FIXME: Avoid strlen.
 165     if (ArgSize != strlen(Args.getArgString(Index)))
 166       return nullptr;
 167
 168     Index += 1 + getNumArgs();
 169     if (Index > Args.getNumInputArgStrings())
 170       return nullptr;
 171
 172     Arg *A = new Arg(*this, Spelling, Index - 1 - getNumArgs(),
 173                      Args.getArgString(Index - getNumArgs()));
 174     for (unsigned i = 1; i != getNumArgs(); ++i)
 175       A->getValues().push_back(Args.getArgString(Index - getNumArgs() + i));
 176     return A;
 177   }
 178   case JoinedOrSeparateClass: {
 179     // If this is not an exact match, it is a joined arg.
 180     // FIXME: Avoid strlen.
 181     if (ArgSize != strlen(Args.getArgString(Index))) {
 182       const char *Value = Args.getArgString(Index) + ArgSize;
 183       return new Arg(*this, Spelling, Index++, Value);
 184     }
 185
 186     // Otherwise it must be separate.
 187     Index += 2;
 188     if (Index > Args.getNumInputArgStrings() ||
 189         Args.getArgString(Index - 1) == nullptr)
 190       return nullptr;
 191
 192     return new Arg(*this, Spelling, Index - 2, Args.getArgString(Index - 1));
 193   }
 194   case JoinedAndSeparateClass:
 195     // Always matches.
 196     Index += 2;
 197     if (Index > Args.getNumInputArgStrings() ||
 198         Args.getArgString(Index - 1) == nullptr)
 199       return nullptr;
 200
 201     return new Arg(*this, Spelling, Index - 2,
 202                    Args.getArgString(Index - 2) + ArgSize,
 203                    Args.getArgString(Index - 1));
 204   case RemainingArgsClass: {
 205     // Matches iff this is an exact match.
 206     // FIXME: Avoid strlen.
 207     if (ArgSize != strlen(Args.getArgString(Index)))
 208       return nullptr;
 209     Arg *A = new Arg(*this, Spelling, Index++);
 210     while (Index < Args.getNumInputArgStrings() &&
 211            Args.getArgString(Index) != nullptr)
 212       A->getValues().push_back(Args.getArgString(Index++));
 213     return A;
 214   }
 215   case RemainingArgsJoinedClass: {
 216     Arg *A = new Arg(*this, Spelling, Index);
 217     if (ArgSize != strlen(Args.getArgString(Index))) {
 218       // An inexact match means there is a joined arg.
 219       A->getValues().push_back(Args.getArgString(Index) + ArgSize);
 220     }
 221     Index++;
 222     while (Index < Args.getNumInputArgStrings() &&
 223            Args.getArgString(Index) != nullptr)
 224       A->getValues().push_back(Args.getArgString(Index++));
 225     return A;
 226   }
 227
 228   default:
 229     llvm_unreachable("Invalid option kind!");
 230   }
 231 }
 232
 233 Arg *Option::accept(const ArgList &Args, StringRef CurArg,
 234                     bool GroupedShortOption, unsigned &Index) const {
 235   std::unique_ptr<Arg> A(GroupedShortOption && getKind() == FlagClass
 236                              ? new Arg(*this, CurArg, Index)
 237                              : acceptInternal(Args, CurArg, Index));
 238   if (!A)
 239     return nullptr;
 240
 241   const Option &UnaliasedOption = getUnaliasedOption();
 242   if (getID() == UnaliasedOption.getID())
 243     return A.release();
 244
 245   // "A" is an alias for a different flag. For most clients it's more convenient
 246   // if this function returns unaliased Args, so create an unaliased arg for
 247   // returning.
 248
 249   // This creates a completely new Arg object for the unaliased Arg because
 250   // the alias and the unaliased arg can have different Kinds and different
 251   // Values (due to AliasArgs<>).
 252
 253   // Get the spelling from the unaliased option.
 254   StringRef UnaliasedSpelling = Args.MakeArgString(
 255       Twine(UnaliasedOption.getPrefix()) + Twine(UnaliasedOption.getName()));
 256
 257   // It's a bit weird that aliased and unaliased arg share one index, but
 258   // the index is mostly use as a memory optimization in render().
 259   // Due to this, ArgList::getArgString(A->getIndex()) will return the spelling
 260   // of the aliased arg always, while A->getSpelling() returns either the
 261   // unaliased or the aliased arg, depending on which Arg object it's called on.
 262   Arg *UnaliasedA = new Arg(UnaliasedOption, UnaliasedSpelling, A->getIndex());
 263   Arg *RawA = A.get();
 264   UnaliasedA->setAlias(std::move(A));
 265
 266   if (getKind() != FlagClass) {
 267     // Values are usually owned by the ArgList. The exception are
 268     // CommaJoined flags, where the Arg owns the values. For aliased flags,
 269     // make the unaliased Arg the owner of the values.
 270     // FIXME: There aren't many uses of CommaJoined -- try removing
 271     // CommaJoined in favor of just calling StringRef::split(',') instead.
 272     UnaliasedA->getValues() = RawA->getValues();
 273     UnaliasedA->setOwnsValues(RawA->getOwnsValues());
 274     RawA->setOwnsValues(false);
 275     return UnaliasedA;
 276   }
 277
 278   // FlagClass aliases can have AliasArgs<>; add those to the unaliased arg.
 279   if (const char *Val = getAliasArgs()) {
 280     while (*Val != '\0') {
 281       UnaliasedA->getValues().push_back(Val);
 282
 283       // Move past the '\0' to the next argument.
 284       Val += strlen(Val) + 1;
 285     }
 286   }
 287   if (UnaliasedOption.getKind() == JoinedClass && !getAliasArgs())
 288     // A Flag alias for a Joined option must provide an argument.
 289     UnaliasedA->getValues().push_back("");
 290   return UnaliasedA;
 291 }