contrib/llvm/tools/clang/lib/Driver/SanitizerArgs.cpp

   1 //===--- SanitizerArgs.cpp - Arguments for sanitizer tools  ---------------===//
   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 #include "clang/Driver/SanitizerArgs.h"
  10 #include "ToolChains/CommonArgs.h"
  11 #include "clang/Basic/Sanitizers.h"
  12 #include "clang/Driver/Driver.h"
  13 #include "clang/Driver/DriverDiagnostic.h"
  14 #include "clang/Driver/Options.h"
  15 #include "clang/Driver/ToolChain.h"
  16 #include "llvm/ADT/StringExtras.h"
  17 #include "llvm/ADT/StringSwitch.h"
  18 #include "llvm/Support/FileSystem.h"
  19 #include "llvm/Support/Path.h"
  20 #include "llvm/Support/SpecialCaseList.h"
  21 #include <memory>
  22
  23 using namespace clang;
  24 using namespace clang::SanitizerKind;
  25 using namespace clang::driver;
  26 using namespace llvm::opt;
  27
  28 enum : SanitizerMask {
  29   NeedsUbsanRt = Undefined | Integer | Nullability | CFI,
  30   NeedsUbsanCxxRt = Vptr | CFI,
  31   NotAllowedWithTrap = Vptr,
  32   RequiresPIE = DataFlow,
  33   NeedsUnwindTables = Address | Thread | Memory | DataFlow,
  34   SupportsCoverage =
  35       Address | Memory | Leak | Undefined | Integer | Nullability | DataFlow,
  36   RecoverableByDefault = Undefined | Integer | Nullability,
  37   Unrecoverable = Unreachable | Return,
  38   LegacyFsanitizeRecoverMask = Undefined | Integer,
  39   NeedsLTO = CFI,
  40   TrappingSupported = (Undefined & ~Vptr) | UnsignedIntegerOverflow |
  41                       Nullability | LocalBounds | CFI,
  42   TrappingDefault = CFI,
  43   CFIClasses = CFIVCall | CFINVCall | CFIDerivedCast | CFIUnrelatedCast,
  44 };
  45
  46 enum CoverageFeature {
  47   CoverageFunc = 1 << 0,
  48   CoverageBB = 1 << 1,
  49   CoverageEdge = 1 << 2,
  50   CoverageIndirCall = 1 << 3,
  51   CoverageTraceBB = 1 << 4,
  52   CoverageTraceCmp = 1 << 5,
  53   CoverageTraceDiv = 1 << 6,
  54   CoverageTraceGep = 1 << 7,
  55   Coverage8bitCounters = 1 << 8,
  56   CoverageTracePC = 1 << 9,
  57   CoverageTracePCGuard = 1 << 10,
  58   CoverageNoPrune = 1 << 11,
  59 };
  60
  61 /// Parse a -fsanitize= or -fno-sanitize= argument's values, diagnosing any
  62 /// invalid components. Returns a SanitizerMask.
  63 static SanitizerMask parseArgValues(const Driver &D, const llvm::opt::Arg *A,
  64                                     bool DiagnoseErrors);
  65
  66 /// Parse -f(no-)?sanitize-coverage= flag values, diagnosing any invalid
  67 /// components. Returns OR of members of \c CoverageFeature enumeration.
  68 static int parseCoverageFeatures(const Driver &D, const llvm::opt::Arg *A);
  69
  70 /// Produce an argument string from ArgList \p Args, which shows how it
  71 /// provides some sanitizer kind from \p Mask. For example, the argument list
  72 /// "-fsanitize=thread,vptr -fsanitize=address" with mask \c NeedsUbsanRt
  73 /// would produce "-fsanitize=vptr".
  74 static std::string lastArgumentForMask(const Driver &D,
  75                                        const llvm::opt::ArgList &Args,
  76                                        SanitizerMask Mask);
  77
  78 /// Produce an argument string from argument \p A, which shows how it provides
  79 /// a value in \p Mask. For instance, the argument
  80 /// "-fsanitize=address,alignment" with mask \c NeedsUbsanRt would produce
  81 /// "-fsanitize=alignment".
  82 static std::string describeSanitizeArg(const llvm::opt::Arg *A,
  83                                        SanitizerMask Mask);
  84
  85 /// Produce a string containing comma-separated names of sanitizers in \p
  86 /// Sanitizers set.
  87 static std::string toString(const clang::SanitizerSet &Sanitizers);
  88
  89 static bool getDefaultBlacklist(const Driver &D, SanitizerMask Kinds,
  90                                 std::string &BLPath) {
  91   const char *BlacklistFile = nullptr;
  92   if (Kinds & Address)
  93     BlacklistFile = "asan_blacklist.txt";
  94   else if (Kinds & Memory)
  95     BlacklistFile = "msan_blacklist.txt";
  96   else if (Kinds & Thread)
  97     BlacklistFile = "tsan_blacklist.txt";
  98   else if (Kinds & DataFlow)
  99     BlacklistFile = "dfsan_abilist.txt";
 100   else if (Kinds & CFI)
 101     BlacklistFile = "cfi_blacklist.txt";
 102
 103   if (BlacklistFile) {
 104     clang::SmallString<64> Path(D.ResourceDir);
 105     llvm::sys::path::append(Path, BlacklistFile);
 106     BLPath = Path.str();
 107     return true;
 108   }
 109   return false;
 110 }
 111
 112 /// Sets group bits for every group that has at least one representative already
 113 /// enabled in \p Kinds.
 114 static SanitizerMask setGroupBits(SanitizerMask Kinds) {
 115 #define SANITIZER(NAME, ID)
 116 #define SANITIZER_GROUP(NAME, ID, ALIAS)                                       \
 117   if (Kinds & SanitizerKind::ID)                                               \
 118     Kinds |= SanitizerKind::ID##Group;
 119 #include "clang/Basic/Sanitizers.def"
 120   return Kinds;
 121 }
 122
 123 static SanitizerMask parseSanitizeTrapArgs(const Driver &D,
 124                                            const llvm::opt::ArgList &Args) {
 125   SanitizerMask TrapRemove = 0; // During the loop below, the accumulated set of
 126                                 // sanitizers disabled by the current sanitizer
 127                                 // argument or any argument after it.
 128   SanitizerMask TrappingKinds = 0;
 129   SanitizerMask TrappingSupportedWithGroups = setGroupBits(TrappingSupported);
 130
 131   for (ArgList::const_reverse_iterator I = Args.rbegin(), E = Args.rend();
 132        I != E; ++I) {
 133     const auto *Arg = *I;
 134     if (Arg->getOption().matches(options::OPT_fsanitize_trap_EQ)) {
 135       Arg->claim();
 136       SanitizerMask Add = parseArgValues(D, Arg, true);
 137       Add &= ~TrapRemove;
 138       if (SanitizerMask InvalidValues = Add & ~TrappingSupportedWithGroups) {
 139         SanitizerSet S;
 140         S.Mask = InvalidValues;
 141         D.Diag(diag::err_drv_unsupported_option_argument) << "-fsanitize-trap"
 142                                                           << toString(S);
 143       }
 144       TrappingKinds |= expandSanitizerGroups(Add) & ~TrapRemove;
 145     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_trap_EQ)) {
 146       Arg->claim();
 147       TrapRemove |= expandSanitizerGroups(parseArgValues(D, Arg, true));
 148     } else if (Arg->getOption().matches(
 149                    options::OPT_fsanitize_undefined_trap_on_error)) {
 150       Arg->claim();
 151       TrappingKinds |=
 152           expandSanitizerGroups(UndefinedGroup & ~TrapRemove) & ~TrapRemove;
 153     } else if (Arg->getOption().matches(
 154                    options::OPT_fno_sanitize_undefined_trap_on_error)) {
 155       Arg->claim();
 156       TrapRemove |= expandSanitizerGroups(UndefinedGroup);
 157     }
 158   }
 159
 160   // Apply default trapping behavior.
 161   TrappingKinds |= TrappingDefault & ~TrapRemove;
 162
 163   return TrappingKinds;
 164 }
 165
 166 bool SanitizerArgs::needsUbsanRt() const {
 167   return ((Sanitizers.Mask & NeedsUbsanRt & ~TrapSanitizers.Mask) ||
 168           CoverageFeatures) &&
 169          !Sanitizers.has(Address) && !Sanitizers.has(Memory) &&
 170          !Sanitizers.has(Thread) && !Sanitizers.has(DataFlow) &&
 171          !Sanitizers.has(Leak) && !CfiCrossDso;
 172 }
 173
 174 bool SanitizerArgs::needsCfiRt() const {
 175   return !(Sanitizers.Mask & CFI & ~TrapSanitizers.Mask) && CfiCrossDso;
 176 }
 177
 178 bool SanitizerArgs::needsCfiDiagRt() const {
 179   return (Sanitizers.Mask & CFI & ~TrapSanitizers.Mask) && CfiCrossDso;
 180 }
 181
 182 bool SanitizerArgs::requiresPIE() const {
 183   return NeedPIE || (Sanitizers.Mask & RequiresPIE);
 184 }
 185
 186 bool SanitizerArgs::needsUnwindTables() const {
 187   return Sanitizers.Mask & NeedsUnwindTables;
 188 }
 189
 190 SanitizerArgs::SanitizerArgs(const ToolChain &TC,
 191                              const llvm::opt::ArgList &Args) {
 192   SanitizerMask AllRemove = 0;  // During the loop below, the accumulated set of
 193                                 // sanitizers disabled by the current sanitizer
 194                                 // argument or any argument after it.
 195   SanitizerMask AllAddedKinds = 0;  // Mask of all sanitizers ever enabled by
 196                                     // -fsanitize= flags (directly or via group
 197                                     // expansion), some of which may be disabled
 198                                     // later. Used to carefully prune
 199                                     // unused-argument diagnostics.
 200   SanitizerMask DiagnosedKinds = 0;  // All Kinds we have diagnosed up to now.
 201                                      // Used to deduplicate diagnostics.
 202   SanitizerMask Kinds = 0;
 203   const SanitizerMask Supported = setGroupBits(TC.getSupportedSanitizers());
 204   ToolChain::RTTIMode RTTIMode = TC.getRTTIMode();
 205
 206   const Driver &D = TC.getDriver();
 207   SanitizerMask TrappingKinds = parseSanitizeTrapArgs(D, Args);
 208   SanitizerMask InvalidTrappingKinds = TrappingKinds & NotAllowedWithTrap;
 209
 210   for (ArgList::const_reverse_iterator I = Args.rbegin(), E = Args.rend();
 211        I != E; ++I) {
 212     const auto *Arg = *I;
 213     if (Arg->getOption().matches(options::OPT_fsanitize_EQ)) {
 214       Arg->claim();
 215       SanitizerMask Add = parseArgValues(D, Arg, true);
 216       AllAddedKinds |= expandSanitizerGroups(Add);
 217
 218       // Avoid diagnosing any sanitizer which is disabled later.
 219       Add &= ~AllRemove;
 220       // At this point we have not expanded groups, so any unsupported
 221       // sanitizers in Add are those which have been explicitly enabled.
 222       // Diagnose them.
 223       if (SanitizerMask KindsToDiagnose =
 224               Add & InvalidTrappingKinds & ~DiagnosedKinds) {
 225         std::string Desc = describeSanitizeArg(*I, KindsToDiagnose);
 226         D.Diag(diag::err_drv_argument_not_allowed_with)
 227             << Desc << "-fsanitize-trap=undefined";
 228         DiagnosedKinds |= KindsToDiagnose;
 229       }
 230       Add &= ~InvalidTrappingKinds;
 231       if (SanitizerMask KindsToDiagnose = Add & ~Supported & ~DiagnosedKinds) {
 232         std::string Desc = describeSanitizeArg(*I, KindsToDiagnose);
 233         D.Diag(diag::err_drv_unsupported_opt_for_target)
 234             << Desc << TC.getTriple().str();
 235         DiagnosedKinds |= KindsToDiagnose;
 236       }
 237       Add &= Supported;
 238
 239       // Test for -fno-rtti + explicit -fsanitizer=vptr before expanding groups
 240       // so we don't error out if -fno-rtti and -fsanitize=undefined were
 241       // passed.
 242       if (Add & Vptr &&
 243           (RTTIMode == ToolChain::RM_DisabledImplicitly ||
 244            RTTIMode == ToolChain::RM_DisabledExplicitly)) {
 245         if (RTTIMode == ToolChain::RM_DisabledImplicitly)
 246           // Warn about not having rtti enabled if the vptr sanitizer is
 247           // explicitly enabled
 248           D.Diag(diag::warn_drv_disabling_vptr_no_rtti_default);
 249         else {
 250           const llvm::opt::Arg *NoRTTIArg = TC.getRTTIArg();
 251           assert(NoRTTIArg &&
 252                  "RTTI disabled explicitly but we have no argument!");
 253           D.Diag(diag::err_drv_argument_not_allowed_with)
 254               << "-fsanitize=vptr" << NoRTTIArg->getAsString(Args);
 255         }
 256
 257         // Take out the Vptr sanitizer from the enabled sanitizers
 258         AllRemove |= Vptr;
 259       }
 260
 261       Add = expandSanitizerGroups(Add);
 262       // Group expansion may have enabled a sanitizer which is disabled later.
 263       Add &= ~AllRemove;
 264       // Silently discard any unsupported sanitizers implicitly enabled through
 265       // group expansion.
 266       Add &= ~InvalidTrappingKinds;
 267       Add &= Supported;
 268
 269       // Enable coverage if the fuzzing flag is set.
 270       if (Add & Fuzzer)
 271         CoverageFeatures |= CoverageTracePCGuard | CoverageIndirCall | CoverageTraceCmp;
 272
 273       Kinds |= Add;
 274     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_EQ)) {
 275       Arg->claim();
 276       SanitizerMask Remove = parseArgValues(D, Arg, true);
 277       AllRemove |= expandSanitizerGroups(Remove);
 278     }
 279   }
 280
 281   // Enable toolchain specific default sanitizers if not explicitly disabled.
 282   Kinds |= TC.getDefaultSanitizers() & ~AllRemove;
 283
 284   // We disable the vptr sanitizer if it was enabled by group expansion but RTTI
 285   // is disabled.
 286   if ((Kinds & Vptr) &&
 287       (RTTIMode == ToolChain::RM_DisabledImplicitly ||
 288        RTTIMode == ToolChain::RM_DisabledExplicitly)) {
 289     Kinds &= ~Vptr;
 290   }
 291
 292   // Check that LTO is enabled if we need it.
 293   if ((Kinds & NeedsLTO) && !D.isUsingLTO()) {
 294     D.Diag(diag::err_drv_argument_only_allowed_with)
 295         << lastArgumentForMask(D, Args, Kinds & NeedsLTO) << "-flto";
 296   }
 297
 298   // Report error if there are non-trapping sanitizers that require
 299   // c++abi-specific  parts of UBSan runtime, and they are not provided by the
 300   // toolchain. We don't have a good way to check the latter, so we just
 301   // check if the toolchan supports vptr.
 302   if (~Supported & Vptr) {
 303     SanitizerMask KindsToDiagnose = Kinds & ~TrappingKinds & NeedsUbsanCxxRt;
 304     // The runtime library supports the Microsoft C++ ABI, but only well enough
 305     // for CFI. FIXME: Remove this once we support vptr on Windows.
 306     if (TC.getTriple().isOSWindows())
 307       KindsToDiagnose &= ~CFI;
 308     if (KindsToDiagnose) {
 309       SanitizerSet S;
 310       S.Mask = KindsToDiagnose;
 311       D.Diag(diag::err_drv_unsupported_opt_for_target)
 312           << ("-fno-sanitize-trap=" + toString(S)) << TC.getTriple().str();
 313       Kinds &= ~KindsToDiagnose;
 314     }
 315   }
 316
 317   // Warn about incompatible groups of sanitizers.
 318   std::pair<SanitizerMask, SanitizerMask> IncompatibleGroups[] = {
 319       std::make_pair(Address, Thread), std::make_pair(Address, Memory),
 320       std::make_pair(Thread, Memory), std::make_pair(Leak, Thread),
 321       std::make_pair(Leak, Memory), std::make_pair(KernelAddress, Address),
 322       std::make_pair(KernelAddress, Leak),
 323       std::make_pair(KernelAddress, Thread),
 324       std::make_pair(KernelAddress, Memory),
 325       std::make_pair(Efficiency, Address),
 326       std::make_pair(Efficiency, Leak),
 327       std::make_pair(Efficiency, Thread),
 328       std::make_pair(Efficiency, Memory),
 329       std::make_pair(Efficiency, KernelAddress)};
 330   for (auto G : IncompatibleGroups) {
 331     SanitizerMask Group = G.first;
 332     if (Kinds & Group) {
 333       if (SanitizerMask Incompatible = Kinds & G.second) {
 334         D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 335             << lastArgumentForMask(D, Args, Group)
 336             << lastArgumentForMask(D, Args, Incompatible);
 337         Kinds &= ~Incompatible;
 338       }
 339     }
 340   }
 341   // FIXME: Currently -fsanitize=leak is silently ignored in the presence of
 342   // -fsanitize=address. Perhaps it should print an error, or perhaps
 343   // -f(-no)sanitize=leak should change whether leak detection is enabled by
 344   // default in ASan?
 345
 346   // Parse -f(no-)?sanitize-recover flags.
 347   SanitizerMask RecoverableKinds = RecoverableByDefault;
 348   SanitizerMask DiagnosedUnrecoverableKinds = 0;
 349   for (const auto *Arg : Args) {
 350     const char *DeprecatedReplacement = nullptr;
 351     if (Arg->getOption().matches(options::OPT_fsanitize_recover)) {
 352       DeprecatedReplacement =
 353           "-fsanitize-recover=undefined,integer' or '-fsanitize-recover=all";
 354       RecoverableKinds |= expandSanitizerGroups(LegacyFsanitizeRecoverMask);
 355       Arg->claim();
 356     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_recover)) {
 357       DeprecatedReplacement = "-fno-sanitize-recover=undefined,integer' or "
 358                               "'-fno-sanitize-recover=all";
 359       RecoverableKinds &= ~expandSanitizerGroups(LegacyFsanitizeRecoverMask);
 360       Arg->claim();
 361     } else if (Arg->getOption().matches(options::OPT_fsanitize_recover_EQ)) {
 362       SanitizerMask Add = parseArgValues(D, Arg, true);
 363       // Report error if user explicitly tries to recover from unrecoverable
 364       // sanitizer.
 365       if (SanitizerMask KindsToDiagnose =
 366               Add & Unrecoverable & ~DiagnosedUnrecoverableKinds) {
 367         SanitizerSet SetToDiagnose;
 368         SetToDiagnose.Mask |= KindsToDiagnose;
 369         D.Diag(diag::err_drv_unsupported_option_argument)
 370             << Arg->getOption().getName() << toString(SetToDiagnose);
 371         DiagnosedUnrecoverableKinds |= KindsToDiagnose;
 372       }
 373       RecoverableKinds |= expandSanitizerGroups(Add);
 374       Arg->claim();
 375     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_recover_EQ)) {
 376       RecoverableKinds &= ~expandSanitizerGroups(parseArgValues(D, Arg, true));
 377       Arg->claim();
 378     }
 379     if (DeprecatedReplacement) {
 380       D.Diag(diag::warn_drv_deprecated_arg) << Arg->getAsString(Args)
 381                                             << DeprecatedReplacement;
 382     }
 383   }
 384   RecoverableKinds &= Kinds;
 385   RecoverableKinds &= ~Unrecoverable;
 386
 387   TrappingKinds &= Kinds;
 388
 389   // Setup blacklist files.
 390   // Add default blacklist from resource directory.
 391   {
 392     std::string BLPath;
 393     if (getDefaultBlacklist(D, Kinds, BLPath) && llvm::sys::fs::exists(BLPath))
 394       BlacklistFiles.push_back(BLPath);
 395   }
 396   // Parse -f(no-)sanitize-blacklist options.
 397   for (const auto *Arg : Args) {
 398     if (Arg->getOption().matches(options::OPT_fsanitize_blacklist)) {
 399       Arg->claim();
 400       std::string BLPath = Arg->getValue();
 401       if (llvm::sys::fs::exists(BLPath)) {
 402         BlacklistFiles.push_back(BLPath);
 403         ExtraDeps.push_back(BLPath);
 404       } else
 405         D.Diag(clang::diag::err_drv_no_such_file) << BLPath;
 406
 407     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_blacklist)) {
 408       Arg->claim();
 409       BlacklistFiles.clear();
 410       ExtraDeps.clear();
 411     }
 412   }
 413   // Validate blacklists format.
 414   {
 415     std::string BLError;
 416     std::unique_ptr<llvm::SpecialCaseList> SCL(
 417         llvm::SpecialCaseList::create(BlacklistFiles, BLError));
 418     if (!SCL.get())
 419       D.Diag(clang::diag::err_drv_malformed_sanitizer_blacklist) << BLError;
 420   }
 421
 422   // Parse -f[no-]sanitize-memory-track-origins[=level] options.
 423   if (AllAddedKinds & Memory) {
 424     if (Arg *A =
 425             Args.getLastArg(options::OPT_fsanitize_memory_track_origins_EQ,
 426                             options::OPT_fsanitize_memory_track_origins,
 427                             options::OPT_fno_sanitize_memory_track_origins)) {
 428       if (A->getOption().matches(options::OPT_fsanitize_memory_track_origins)) {
 429         MsanTrackOrigins = 2;
 430       } else if (A->getOption().matches(
 431                      options::OPT_fno_sanitize_memory_track_origins)) {
 432         MsanTrackOrigins = 0;
 433       } else {
 434         StringRef S = A->getValue();
 435         if (S.getAsInteger(0, MsanTrackOrigins) || MsanTrackOrigins < 0 ||
 436             MsanTrackOrigins > 2) {
 437           D.Diag(clang::diag::err_drv_invalid_value) << A->getAsString(Args) << S;
 438         }
 439       }
 440     }
 441     MsanUseAfterDtor =
 442         Args.hasArg(options::OPT_fsanitize_memory_use_after_dtor);
 443     NeedPIE |= !(TC.getTriple().isOSLinux() &&
 444                  TC.getTriple().getArch() == llvm::Triple::x86_64);
 445   }
 446
 447   if (AllAddedKinds & Thread) {
 448     TsanMemoryAccess = Args.hasFlag(options::OPT_fsanitize_thread_memory_access,
 449                                     options::OPT_fno_sanitize_thread_memory_access,
 450                                     TsanMemoryAccess);
 451     TsanFuncEntryExit = Args.hasFlag(options::OPT_fsanitize_thread_func_entry_exit,
 452                                      options::OPT_fno_sanitize_thread_func_entry_exit,
 453                                      TsanFuncEntryExit);
 454     TsanAtomics = Args.hasFlag(options::OPT_fsanitize_thread_atomics,
 455                                options::OPT_fno_sanitize_thread_atomics,
 456                                TsanAtomics);
 457   }
 458
 459   if (AllAddedKinds & CFI) {
 460     CfiCrossDso = Args.hasFlag(options::OPT_fsanitize_cfi_cross_dso,
 461                                options::OPT_fno_sanitize_cfi_cross_dso, false);
 462     // Without PIE, external function address may resolve to a PLT record, which
 463     // can not be verified by the target module.
 464     NeedPIE |= CfiCrossDso;
 465   }
 466
 467   Stats = Args.hasFlag(options::OPT_fsanitize_stats,
 468                        options::OPT_fno_sanitize_stats, false);
 469
 470   // Parse -f(no-)?sanitize-coverage flags if coverage is supported by the
 471   // enabled sanitizers.
 472   for (const auto *Arg : Args) {
 473     if (Arg->getOption().matches(options::OPT_fsanitize_coverage)) {
 474       int LegacySanitizeCoverage;
 475       if (Arg->getNumValues() == 1 &&
 476           !StringRef(Arg->getValue(0))
 477                .getAsInteger(0, LegacySanitizeCoverage)) {
 478         CoverageFeatures = 0;
 479         Arg->claim();
 480         if (LegacySanitizeCoverage != 0) {
 481           D.Diag(diag::warn_drv_deprecated_arg)
 482               << Arg->getAsString(Args) << "-fsanitize-coverage=trace-pc-guard";
 483         }
 484         continue;
 485       }
 486       CoverageFeatures |= parseCoverageFeatures(D, Arg);
 487
 488       // Disable coverage and not claim the flags if there is at least one
 489       // non-supporting sanitizer.
 490       if (!(AllAddedKinds & ~setGroupBits(SupportsCoverage))) {
 491         Arg->claim();
 492       } else {
 493         CoverageFeatures = 0;
 494       }
 495     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_coverage)) {
 496       Arg->claim();
 497       CoverageFeatures &= ~parseCoverageFeatures(D, Arg);
 498     }
 499   }
 500   // Choose at most one coverage type: function, bb, or edge.
 501   if ((CoverageFeatures & CoverageFunc) && (CoverageFeatures & CoverageBB))
 502     D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 503         << "-fsanitize-coverage=func"
 504         << "-fsanitize-coverage=bb";
 505   if ((CoverageFeatures & CoverageFunc) && (CoverageFeatures & CoverageEdge))
 506     D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 507         << "-fsanitize-coverage=func"
 508         << "-fsanitize-coverage=edge";
 509   if ((CoverageFeatures & CoverageBB) && (CoverageFeatures & CoverageEdge))
 510     D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 511         << "-fsanitize-coverage=bb"
 512         << "-fsanitize-coverage=edge";
 513   // Basic block tracing and 8-bit counters require some type of coverage
 514   // enabled.
 515   if (CoverageFeatures & CoverageTraceBB)
 516     D.Diag(clang::diag::warn_drv_deprecated_arg)
 517         << "-fsanitize-coverage=trace-bb"
 518         << "-fsanitize-coverage=trace-pc-guard";
 519   if (CoverageFeatures & Coverage8bitCounters)
 520     D.Diag(clang::diag::warn_drv_deprecated_arg)
 521         << "-fsanitize-coverage=8bit-counters"
 522         << "-fsanitize-coverage=trace-pc-guard";
 523
 524   int InsertionPointTypes = CoverageFunc | CoverageBB | CoverageEdge;
 525   if ((CoverageFeatures & InsertionPointTypes) &&
 526       !(CoverageFeatures &(CoverageTracePC | CoverageTracePCGuard))) {
 527     D.Diag(clang::diag::warn_drv_deprecated_arg)
 528         << "-fsanitize-coverage=[func|bb|edge]"
 529         << "-fsanitize-coverage=[func|bb|edge],[trace-pc-guard|trace-pc]";
 530   }
 531
 532   // trace-pc w/o func/bb/edge implies edge.
 533   if ((CoverageFeatures & (CoverageTracePC | CoverageTracePCGuard)) &&
 534       !(CoverageFeatures & InsertionPointTypes))
 535     CoverageFeatures |= CoverageEdge;
 536
 537   if (AllAddedKinds & Address) {
 538     AsanSharedRuntime =
 539         Args.hasArg(options::OPT_shared_libasan) || TC.getTriple().isAndroid();
 540     NeedPIE |= TC.getTriple().isAndroid();
 541     if (Arg *A =
 542             Args.getLastArg(options::OPT_fsanitize_address_field_padding)) {
 543         StringRef S = A->getValue();
 544         // Legal values are 0 and 1, 2, but in future we may add more levels.
 545         if (S.getAsInteger(0, AsanFieldPadding) || AsanFieldPadding < 0 ||
 546             AsanFieldPadding > 2) {
 547           D.Diag(clang::diag::err_drv_invalid_value) << A->getAsString(Args) << S;
 548         }
 549     }
 550
 551     if (Arg *WindowsDebugRTArg =
 552             Args.getLastArg(options::OPT__SLASH_MTd, options::OPT__SLASH_MT,
 553                             options::OPT__SLASH_MDd, options::OPT__SLASH_MD,
 554                             options::OPT__SLASH_LDd, options::OPT__SLASH_LD)) {
 555       switch (WindowsDebugRTArg->getOption().getID()) {
 556       case options::OPT__SLASH_MTd:
 557       case options::OPT__SLASH_MDd:
 558       case options::OPT__SLASH_LDd:
 559         D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 560             << WindowsDebugRTArg->getAsString(Args)
 561             << lastArgumentForMask(D, Args, Address);
 562         D.Diag(clang::diag::note_drv_address_sanitizer_debug_runtime);
 563       }
 564     }
 565
 566     AsanUseAfterScope = Args.hasFlag(
 567         options::OPT_fsanitize_address_use_after_scope,
 568         options::OPT_fno_sanitize_address_use_after_scope, AsanUseAfterScope);
 569
 570     // As a workaround for a bug in gold 2.26 and earlier, dead stripping of
 571     // globals in ASan is disabled by default on ELF targets.
 572     // See https://sourceware.org/bugzilla/show_bug.cgi?id=19002
 573     AsanGlobalsDeadStripping =
 574         !TC.getTriple().isOSBinFormatELF() ||
 575         Args.hasArg(options::OPT_fsanitize_address_globals_dead_stripping);
 576   } else {
 577     AsanUseAfterScope = false;
 578   }
 579
 580   // Parse -link-cxx-sanitizer flag.
 581   LinkCXXRuntimes =
 582       Args.hasArg(options::OPT_fsanitize_link_cxx_runtime) || D.CCCIsCXX();
 583
 584   // Finally, initialize the set of available and recoverable sanitizers.
 585   Sanitizers.Mask |= Kinds;
 586   RecoverableSanitizers.Mask |= RecoverableKinds;
 587   TrapSanitizers.Mask |= TrappingKinds;
 588 }
 589
 590 static std::string toString(const clang::SanitizerSet &Sanitizers) {
 591   std::string Res;
 592 #define SANITIZER(NAME, ID)                                                    \
 593   if (Sanitizers.has(ID)) {                                                    \
 594     if (!Res.empty())                                                          \
 595       Res += ",";                                                              \
 596     Res += NAME;                                                               \
 597   }
 598 #include "clang/Basic/Sanitizers.def"
 599   return Res;
 600 }
 601
 602 static void addIncludeLinkerOption(const ToolChain &TC,
 603                                    const llvm::opt::ArgList &Args,
 604                                    llvm::opt::ArgStringList &CmdArgs,
 605                                    StringRef SymbolName) {
 606   SmallString<64> LinkerOptionFlag;
 607   LinkerOptionFlag = "--linker-option=/include:";
 608   if (TC.getTriple().getArch() == llvm::Triple::x86) {
 609     // Win32 mangles C function names with a '_' prefix.
 610     LinkerOptionFlag += '_';
 611   }
 612   LinkerOptionFlag += SymbolName;
 613   CmdArgs.push_back(Args.MakeArgString(LinkerOptionFlag));
 614 }
 615
 616 void SanitizerArgs::addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
 617                             llvm::opt::ArgStringList &CmdArgs,
 618                             types::ID InputType) const {
 619   // NVPTX doesn't currently support sanitizers.  Bailing out here means that
 620   // e.g. -fsanitize=address applies only to host code, which is what we want
 621   // for now.
 622   if (TC.getTriple().isNVPTX())
 623     return;
 624
 625   // Translate available CoverageFeatures to corresponding clang-cc1 flags.
 626   // Do it even if Sanitizers.empty() since some forms of coverage don't require
 627   // sanitizers.
 628   std::pair<int, const char *> CoverageFlags[] = {
 629     std::make_pair(CoverageFunc, "-fsanitize-coverage-type=1"),
 630     std::make_pair(CoverageBB, "-fsanitize-coverage-type=2"),
 631     std::make_pair(CoverageEdge, "-fsanitize-coverage-type=3"),
 632     std::make_pair(CoverageIndirCall, "-fsanitize-coverage-indirect-calls"),
 633     std::make_pair(CoverageTraceBB, "-fsanitize-coverage-trace-bb"),
 634     std::make_pair(CoverageTraceCmp, "-fsanitize-coverage-trace-cmp"),
 635     std::make_pair(CoverageTraceDiv, "-fsanitize-coverage-trace-div"),
 636     std::make_pair(CoverageTraceGep, "-fsanitize-coverage-trace-gep"),
 637     std::make_pair(Coverage8bitCounters, "-fsanitize-coverage-8bit-counters"),
 638     std::make_pair(CoverageTracePC, "-fsanitize-coverage-trace-pc"),
 639     std::make_pair(CoverageTracePCGuard, "-fsanitize-coverage-trace-pc-guard"),
 640     std::make_pair(CoverageNoPrune, "-fsanitize-coverage-no-prune")};
 641   for (auto F : CoverageFlags) {
 642     if (CoverageFeatures & F.first)
 643       CmdArgs.push_back(F.second);
 644   }
 645
 646   if (TC.getTriple().isOSWindows() && needsUbsanRt()) {
 647     // Instruct the code generator to embed linker directives in the object file
 648     // that cause the required runtime libraries to be linked.
 649     CmdArgs.push_back(Args.MakeArgString(
 650         "--dependent-lib=" + TC.getCompilerRT(Args, "ubsan_standalone")));
 651     if (types::isCXX(InputType))
 652       CmdArgs.push_back(Args.MakeArgString(
 653           "--dependent-lib=" + TC.getCompilerRT(Args, "ubsan_standalone_cxx")));
 654   }
 655   if (TC.getTriple().isOSWindows() && needsStatsRt()) {
 656     CmdArgs.push_back(Args.MakeArgString("--dependent-lib=" +
 657                                          TC.getCompilerRT(Args, "stats_client")));
 658
 659     // The main executable must export the stats runtime.
 660     // FIXME: Only exporting from the main executable (e.g. based on whether the
 661     // translation unit defines main()) would save a little space, but having
 662     // multiple copies of the runtime shouldn't hurt.
 663     CmdArgs.push_back(Args.MakeArgString("--dependent-lib=" +
 664                                          TC.getCompilerRT(Args, "stats")));
 665     addIncludeLinkerOption(TC, Args, CmdArgs, "__sanitizer_stats_register");
 666   }
 667
 668   if (Sanitizers.empty())
 669     return;
 670   CmdArgs.push_back(Args.MakeArgString("-fsanitize=" + toString(Sanitizers)));
 671
 672   if (!RecoverableSanitizers.empty())
 673     CmdArgs.push_back(Args.MakeArgString("-fsanitize-recover=" +
 674                                          toString(RecoverableSanitizers)));
 675
 676   if (!TrapSanitizers.empty())
 677     CmdArgs.push_back(
 678         Args.MakeArgString("-fsanitize-trap=" + toString(TrapSanitizers)));
 679
 680   for (const auto &BLPath : BlacklistFiles) {
 681     SmallString<64> BlacklistOpt("-fsanitize-blacklist=");
 682     BlacklistOpt += BLPath;
 683     CmdArgs.push_back(Args.MakeArgString(BlacklistOpt));
 684   }
 685   for (const auto &Dep : ExtraDeps) {
 686     SmallString<64> ExtraDepOpt("-fdepfile-entry=");
 687     ExtraDepOpt += Dep;
 688     CmdArgs.push_back(Args.MakeArgString(ExtraDepOpt));
 689   }
 690
 691   if (MsanTrackOrigins)
 692     CmdArgs.push_back(Args.MakeArgString("-fsanitize-memory-track-origins=" +
 693                                          llvm::utostr(MsanTrackOrigins)));
 694
 695   if (MsanUseAfterDtor)
 696     CmdArgs.push_back("-fsanitize-memory-use-after-dtor");
 697
 698   // FIXME: Pass these parameters as function attributes, not as -llvm flags.
 699   if (!TsanMemoryAccess) {
 700     CmdArgs.push_back("-mllvm");
 701     CmdArgs.push_back("-tsan-instrument-memory-accesses=0");
 702     CmdArgs.push_back("-mllvm");
 703     CmdArgs.push_back("-tsan-instrument-memintrinsics=0");
 704   }
 705   if (!TsanFuncEntryExit) {
 706     CmdArgs.push_back("-mllvm");
 707     CmdArgs.push_back("-tsan-instrument-func-entry-exit=0");
 708   }
 709   if (!TsanAtomics) {
 710     CmdArgs.push_back("-mllvm");
 711     CmdArgs.push_back("-tsan-instrument-atomics=0");
 712   }
 713
 714   if (CfiCrossDso)
 715     CmdArgs.push_back("-fsanitize-cfi-cross-dso");
 716
 717   if (Stats)
 718     CmdArgs.push_back("-fsanitize-stats");
 719
 720   if (AsanFieldPadding)
 721     CmdArgs.push_back(Args.MakeArgString("-fsanitize-address-field-padding=" +
 722                                          llvm::utostr(AsanFieldPadding)));
 723
 724   if (AsanUseAfterScope)
 725     CmdArgs.push_back("-fsanitize-address-use-after-scope");
 726
 727   if (AsanGlobalsDeadStripping)
 728     CmdArgs.push_back("-fsanitize-address-globals-dead-stripping");
 729
 730   // MSan: Workaround for PR16386.
 731   // ASan: This is mainly to help LSan with cases such as
 732   // https://code.google.com/p/address-sanitizer/issues/detail?id=373
 733   // We can't make this conditional on -fsanitize=leak, as that flag shouldn't
 734   // affect compilation.
 735   if (Sanitizers.has(Memory) || Sanitizers.has(Address))
 736     CmdArgs.push_back("-fno-assume-sane-operator-new");
 737
 738   // Require -fvisibility= flag on non-Windows when compiling if vptr CFI is
 739   // enabled.
 740   if (Sanitizers.hasOneOf(CFIClasses) && !TC.getTriple().isOSWindows() &&
 741       !Args.hasArg(options::OPT_fvisibility_EQ)) {
 742     TC.getDriver().Diag(clang::diag::err_drv_argument_only_allowed_with)
 743         << lastArgumentForMask(TC.getDriver(), Args,
 744                                Sanitizers.Mask & CFIClasses)
 745         << "-fvisibility=";
 746   }
 747 }
 748
 749 SanitizerMask parseArgValues(const Driver &D, const llvm::opt::Arg *A,
 750                              bool DiagnoseErrors) {
 751   assert((A->getOption().matches(options::OPT_fsanitize_EQ) ||
 752           A->getOption().matches(options::OPT_fno_sanitize_EQ) ||
 753           A->getOption().matches(options::OPT_fsanitize_recover_EQ) ||
 754           A->getOption().matches(options::OPT_fno_sanitize_recover_EQ) ||
 755           A->getOption().matches(options::OPT_fsanitize_trap_EQ) ||
 756           A->getOption().matches(options::OPT_fno_sanitize_trap_EQ)) &&
 757          "Invalid argument in parseArgValues!");
 758   SanitizerMask Kinds = 0;
 759   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
 760     const char *Value = A->getValue(i);
 761     SanitizerMask Kind;
 762     // Special case: don't accept -fsanitize=all.
 763     if (A->getOption().matches(options::OPT_fsanitize_EQ) &&
 764         0 == strcmp("all", Value))
 765       Kind = 0;
 766     // Similarly, don't accept -fsanitize=efficiency-all.
 767     else if (A->getOption().matches(options::OPT_fsanitize_EQ) &&
 768         0 == strcmp("efficiency-all", Value))
 769       Kind = 0;
 770     else
 771       Kind = parseSanitizerValue(Value, /*AllowGroups=*/true);
 772
 773     if (Kind)
 774       Kinds |= Kind;
 775     else if (DiagnoseErrors)
 776       D.Diag(clang::diag::err_drv_unsupported_option_argument)
 777           << A->getOption().getName() << Value;
 778   }
 779   return Kinds;
 780 }
 781
 782 int parseCoverageFeatures(const Driver &D, const llvm::opt::Arg *A) {
 783   assert(A->getOption().matches(options::OPT_fsanitize_coverage) ||
 784          A->getOption().matches(options::OPT_fno_sanitize_coverage));
 785   int Features = 0;
 786   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
 787     const char *Value = A->getValue(i);
 788     int F = llvm::StringSwitch<int>(Value)
 789         .Case("func", CoverageFunc)
 790         .Case("bb", CoverageBB)
 791         .Case("edge", CoverageEdge)
 792         .Case("indirect-calls", CoverageIndirCall)
 793         .Case("trace-bb", CoverageTraceBB)
 794         .Case("trace-cmp", CoverageTraceCmp)
 795         .Case("trace-div", CoverageTraceDiv)
 796         .Case("trace-gep", CoverageTraceGep)
 797         .Case("8bit-counters", Coverage8bitCounters)
 798         .Case("trace-pc", CoverageTracePC)
 799         .Case("trace-pc-guard", CoverageTracePCGuard)
 800         .Case("no-prune", CoverageNoPrune)
 801         .Default(0);
 802     if (F == 0)
 803       D.Diag(clang::diag::err_drv_unsupported_option_argument)
 804           << A->getOption().getName() << Value;
 805     Features |= F;
 806   }
 807   return Features;
 808 }
 809
 810 std::string lastArgumentForMask(const Driver &D, const llvm::opt::ArgList &Args,
 811                                 SanitizerMask Mask) {
 812   for (llvm::opt::ArgList::const_reverse_iterator I = Args.rbegin(),
 813                                                   E = Args.rend();
 814        I != E; ++I) {
 815     const auto *Arg = *I;
 816     if (Arg->getOption().matches(options::OPT_fsanitize_EQ)) {
 817       SanitizerMask AddKinds =
 818           expandSanitizerGroups(parseArgValues(D, Arg, false));
 819       if (AddKinds & Mask)
 820         return describeSanitizeArg(Arg, Mask);
 821     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_EQ)) {
 822       SanitizerMask RemoveKinds =
 823           expandSanitizerGroups(parseArgValues(D, Arg, false));
 824       Mask &= ~RemoveKinds;
 825     }
 826   }
 827   llvm_unreachable("arg list didn't provide expected value");
 828 }
 829
 830 std::string describeSanitizeArg(const llvm::opt::Arg *A, SanitizerMask Mask) {
 831   assert(A->getOption().matches(options::OPT_fsanitize_EQ)
 832          && "Invalid argument in describeSanitizerArg!");
 833
 834   std::string Sanitizers;
 835   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
 836     if (expandSanitizerGroups(
 837             parseSanitizerValue(A->getValue(i), /*AllowGroups=*/true)) &
 838         Mask) {
 839       if (!Sanitizers.empty())
 840         Sanitizers += ",";
 841       Sanitizers += A->getValue(i);
 842     }
 843   }
 844
 845   assert(!Sanitizers.empty() && "arg didn't provide expected value");
 846   return "-fsanitize=" + Sanitizers;
 847 }