contrib/llvm-project/clang/lib/Driver/SanitizerArgs.cpp

   1 //===--- SanitizerArgs.cpp - Arguments for sanitizer tools  ---------------===//
   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 #include "clang/Driver/SanitizerArgs.h"
   9 #include "ToolChains/CommonArgs.h"
  10 #include "clang/Basic/Sanitizers.h"
  11 #include "clang/Driver/Driver.h"
  12 #include "clang/Driver/DriverDiagnostic.h"
  13 #include "clang/Driver/Options.h"
  14 #include "clang/Driver/ToolChain.h"
  15 #include "llvm/ADT/StringExtras.h"
  16 #include "llvm/ADT/StringSwitch.h"
  17 #include "llvm/Support/FileSystem.h"
  18 #include "llvm/Support/Path.h"
  19 #include "llvm/Support/SpecialCaseList.h"
  20 #include "llvm/Support/TargetParser.h"
  21 #include <memory>
  22
  23 using namespace clang;
  24 using namespace clang::driver;
  25 using namespace llvm::opt;
  26
  27 static const SanitizerMask NeedsUbsanRt =
  28     SanitizerKind::Undefined | SanitizerKind::Integer |
  29     SanitizerKind::ImplicitConversion | SanitizerKind::Nullability |
  30     SanitizerKind::CFI | SanitizerKind::FloatDivideByZero;
  31 static const SanitizerMask NeedsUbsanCxxRt =
  32     SanitizerKind::Vptr | SanitizerKind::CFI;
  33 static const SanitizerMask NotAllowedWithTrap = SanitizerKind::Vptr;
  34 static const SanitizerMask NotAllowedWithMinimalRuntime =
  35     SanitizerKind::Function | SanitizerKind::Vptr;
  36 static const SanitizerMask RequiresPIE =
  37     SanitizerKind::DataFlow | SanitizerKind::HWAddress | SanitizerKind::Scudo;
  38 static const SanitizerMask NeedsUnwindTables =
  39     SanitizerKind::Address | SanitizerKind::HWAddress | SanitizerKind::Thread |
  40     SanitizerKind::Memory | SanitizerKind::DataFlow;
  41 static const SanitizerMask SupportsCoverage =
  42     SanitizerKind::Address | SanitizerKind::HWAddress |
  43     SanitizerKind::KernelAddress | SanitizerKind::KernelHWAddress |
  44     SanitizerKind::MemTag | SanitizerKind::Memory |
  45     SanitizerKind::KernelMemory | SanitizerKind::Leak |
  46     SanitizerKind::Undefined | SanitizerKind::Integer |
  47     SanitizerKind::ImplicitConversion | SanitizerKind::Nullability |
  48     SanitizerKind::DataFlow | SanitizerKind::Fuzzer |
  49     SanitizerKind::FuzzerNoLink | SanitizerKind::FloatDivideByZero |
  50     SanitizerKind::SafeStack | SanitizerKind::ShadowCallStack;
  51 static const SanitizerMask RecoverableByDefault =
  52     SanitizerKind::Undefined | SanitizerKind::Integer |
  53     SanitizerKind::ImplicitConversion | SanitizerKind::Nullability |
  54     SanitizerKind::FloatDivideByZero;
  55 static const SanitizerMask Unrecoverable =
  56     SanitizerKind::Unreachable | SanitizerKind::Return;
  57 static const SanitizerMask AlwaysRecoverable =
  58     SanitizerKind::KernelAddress | SanitizerKind::KernelHWAddress;
  59 static const SanitizerMask LegacyFsanitizeRecoverMask =
  60     SanitizerKind::Undefined | SanitizerKind::Integer;
  61 static const SanitizerMask NeedsLTO = SanitizerKind::CFI;
  62 static const SanitizerMask TrappingSupported =
  63     (SanitizerKind::Undefined & ~SanitizerKind::Vptr) |
  64     SanitizerKind::UnsignedIntegerOverflow | SanitizerKind::ImplicitConversion |
  65     SanitizerKind::Nullability | SanitizerKind::LocalBounds |
  66     SanitizerKind::CFI | SanitizerKind::FloatDivideByZero;
  67 static const SanitizerMask TrappingDefault = SanitizerKind::CFI;
  68 static const SanitizerMask CFIClasses =
  69     SanitizerKind::CFIVCall | SanitizerKind::CFINVCall |
  70     SanitizerKind::CFIMFCall | SanitizerKind::CFIDerivedCast |
  71     SanitizerKind::CFIUnrelatedCast;
  72 static const SanitizerMask CompatibleWithMinimalRuntime =
  73     TrappingSupported | SanitizerKind::Scudo | SanitizerKind::ShadowCallStack;
  74
  75 enum CoverageFeature {
  76   CoverageFunc = 1 << 0,
  77   CoverageBB = 1 << 1,
  78   CoverageEdge = 1 << 2,
  79   CoverageIndirCall = 1 << 3,
  80   CoverageTraceBB = 1 << 4,  // Deprecated.
  81   CoverageTraceCmp = 1 << 5,
  82   CoverageTraceDiv = 1 << 6,
  83   CoverageTraceGep = 1 << 7,
  84   Coverage8bitCounters = 1 << 8,  // Deprecated.
  85   CoverageTracePC = 1 << 9,
  86   CoverageTracePCGuard = 1 << 10,
  87   CoverageNoPrune = 1 << 11,
  88   CoverageInline8bitCounters = 1 << 12,
  89   CoveragePCTable = 1 << 13,
  90   CoverageStackDepth = 1 << 14,
  91 };
  92
  93 /// Parse a -fsanitize= or -fno-sanitize= argument's values, diagnosing any
  94 /// invalid components. Returns a SanitizerMask.
  95 static SanitizerMask parseArgValues(const Driver &D, const llvm::opt::Arg *A,
  96                                     bool DiagnoseErrors);
  97
  98 /// Parse -f(no-)?sanitize-coverage= flag values, diagnosing any invalid
  99 /// components. Returns OR of members of \c CoverageFeature enumeration.
 100 static int parseCoverageFeatures(const Driver &D, const llvm::opt::Arg *A);
 101
 102 /// Produce an argument string from ArgList \p Args, which shows how it
 103 /// provides some sanitizer kind from \p Mask. For example, the argument list
 104 /// "-fsanitize=thread,vptr -fsanitize=address" with mask \c NeedsUbsanRt
 105 /// would produce "-fsanitize=vptr".
 106 static std::string lastArgumentForMask(const Driver &D,
 107                                        const llvm::opt::ArgList &Args,
 108                                        SanitizerMask Mask);
 109
 110 /// Produce an argument string from argument \p A, which shows how it provides
 111 /// a value in \p Mask. For instance, the argument
 112 /// "-fsanitize=address,alignment" with mask \c NeedsUbsanRt would produce
 113 /// "-fsanitize=alignment".
 114 static std::string describeSanitizeArg(const llvm::opt::Arg *A,
 115                                        SanitizerMask Mask);
 116
 117 /// Produce a string containing comma-separated names of sanitizers in \p
 118 /// Sanitizers set.
 119 static std::string toString(const clang::SanitizerSet &Sanitizers);
 120
 121 static void addDefaultBlacklists(const Driver &D, SanitizerMask Kinds,
 122                                  std::vector<std::string> &BlacklistFiles) {
 123   struct Blacklist {
 124     const char *File;
 125     SanitizerMask Mask;
 126   } Blacklists[] = {{"asan_blacklist.txt", SanitizerKind::Address},
 127                     {"hwasan_blacklist.txt", SanitizerKind::HWAddress},
 128                     {"memtag_blacklist.txt", SanitizerKind::MemTag},
 129                     {"msan_blacklist.txt", SanitizerKind::Memory},
 130                     {"tsan_blacklist.txt", SanitizerKind::Thread},
 131                     {"dfsan_abilist.txt", SanitizerKind::DataFlow},
 132                     {"cfi_blacklist.txt", SanitizerKind::CFI},
 133                     {"ubsan_blacklist.txt",
 134                      SanitizerKind::Undefined | SanitizerKind::Integer |
 135                          SanitizerKind::Nullability |
 136                          SanitizerKind::FloatDivideByZero}};
 137
 138   for (auto BL : Blacklists) {
 139     if (!(Kinds & BL.Mask))
 140       continue;
 141
 142     clang::SmallString<64> Path(D.ResourceDir);
 143     llvm::sys::path::append(Path, "share", BL.File);
 144     if (llvm::sys::fs::exists(Path))
 145       BlacklistFiles.push_back(Path.str());
 146     else if (BL.Mask == SanitizerKind::CFI)
 147       // If cfi_blacklist.txt cannot be found in the resource dir, driver
 148       // should fail.
 149       D.Diag(clang::diag::err_drv_no_such_file) << Path;
 150   }
 151 }
 152
 153 /// Sets group bits for every group that has at least one representative already
 154 /// enabled in \p Kinds.
 155 static SanitizerMask setGroupBits(SanitizerMask Kinds) {
 156 #define SANITIZER(NAME, ID)
 157 #define SANITIZER_GROUP(NAME, ID, ALIAS)                                       \
 158   if (Kinds & SanitizerKind::ID)                                               \
 159     Kinds |= SanitizerKind::ID##Group;
 160 #include "clang/Basic/Sanitizers.def"
 161   return Kinds;
 162 }
 163
 164 static SanitizerMask parseSanitizeTrapArgs(const Driver &D,
 165                                            const llvm::opt::ArgList &Args) {
 166   SanitizerMask TrapRemove;     // During the loop below, the accumulated set of
 167                                 // sanitizers disabled by the current sanitizer
 168                                 // argument or any argument after it.
 169   SanitizerMask TrappingKinds;
 170   SanitizerMask TrappingSupportedWithGroups = setGroupBits(TrappingSupported);
 171
 172   for (ArgList::const_reverse_iterator I = Args.rbegin(), E = Args.rend();
 173        I != E; ++I) {
 174     const auto *Arg = *I;
 175     if (Arg->getOption().matches(options::OPT_fsanitize_trap_EQ)) {
 176       Arg->claim();
 177       SanitizerMask Add = parseArgValues(D, Arg, true);
 178       Add &= ~TrapRemove;
 179       if (SanitizerMask InvalidValues = Add & ~TrappingSupportedWithGroups) {
 180         SanitizerSet S;
 181         S.Mask = InvalidValues;
 182         D.Diag(diag::err_drv_unsupported_option_argument) << "-fsanitize-trap"
 183                                                           << toString(S);
 184       }
 185       TrappingKinds |= expandSanitizerGroups(Add) & ~TrapRemove;
 186     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_trap_EQ)) {
 187       Arg->claim();
 188       TrapRemove |= expandSanitizerGroups(parseArgValues(D, Arg, true));
 189     } else if (Arg->getOption().matches(
 190                    options::OPT_fsanitize_undefined_trap_on_error)) {
 191       Arg->claim();
 192       TrappingKinds |=
 193           expandSanitizerGroups(SanitizerKind::UndefinedGroup & ~TrapRemove) &
 194           ~TrapRemove;
 195     } else if (Arg->getOption().matches(
 196                    options::OPT_fno_sanitize_undefined_trap_on_error)) {
 197       Arg->claim();
 198       TrapRemove |= expandSanitizerGroups(SanitizerKind::UndefinedGroup);
 199     }
 200   }
 201
 202   // Apply default trapping behavior.
 203   TrappingKinds |= TrappingDefault & ~TrapRemove;
 204
 205   return TrappingKinds;
 206 }
 207
 208 bool SanitizerArgs::needsUbsanRt() const {
 209   // All of these include ubsan.
 210   if (needsAsanRt() || needsMsanRt() || needsHwasanRt() || needsTsanRt() ||
 211       needsDfsanRt() || needsLsanRt() || needsCfiDiagRt() ||
 212       (needsScudoRt() && !requiresMinimalRuntime()))
 213     return false;
 214
 215   return (Sanitizers.Mask & NeedsUbsanRt & ~TrapSanitizers.Mask) ||
 216          CoverageFeatures;
 217 }
 218
 219 bool SanitizerArgs::needsCfiRt() const {
 220   return !(Sanitizers.Mask & SanitizerKind::CFI & ~TrapSanitizers.Mask) &&
 221          CfiCrossDso && !ImplicitCfiRuntime;
 222 }
 223
 224 bool SanitizerArgs::needsCfiDiagRt() const {
 225   return (Sanitizers.Mask & SanitizerKind::CFI & ~TrapSanitizers.Mask) &&
 226          CfiCrossDso && !ImplicitCfiRuntime;
 227 }
 228
 229 bool SanitizerArgs::requiresPIE() const {
 230   return NeedPIE || (Sanitizers.Mask & RequiresPIE);
 231 }
 232
 233 bool SanitizerArgs::needsUnwindTables() const {
 234   return static_cast<bool>(Sanitizers.Mask & NeedsUnwindTables);
 235 }
 236
 237 bool SanitizerArgs::needsLTO() const {
 238   return static_cast<bool>(Sanitizers.Mask & NeedsLTO);
 239 }
 240
 241 SanitizerArgs::SanitizerArgs(const ToolChain &TC,
 242                              const llvm::opt::ArgList &Args) {
 243   SanitizerMask AllRemove;      // During the loop below, the accumulated set of
 244                                 // sanitizers disabled by the current sanitizer
 245                                 // argument or any argument after it.
 246   SanitizerMask AllAddedKinds;      // Mask of all sanitizers ever enabled by
 247                                     // -fsanitize= flags (directly or via group
 248                                     // expansion), some of which may be disabled
 249                                     // later. Used to carefully prune
 250                                     // unused-argument diagnostics.
 251   SanitizerMask DiagnosedKinds;      // All Kinds we have diagnosed up to now.
 252                                      // Used to deduplicate diagnostics.
 253   SanitizerMask Kinds;
 254   const SanitizerMask Supported = setGroupBits(TC.getSupportedSanitizers());
 255
 256   CfiCrossDso = Args.hasFlag(options::OPT_fsanitize_cfi_cross_dso,
 257                              options::OPT_fno_sanitize_cfi_cross_dso, false);
 258
 259   ToolChain::RTTIMode RTTIMode = TC.getRTTIMode();
 260
 261   const Driver &D = TC.getDriver();
 262   SanitizerMask TrappingKinds = parseSanitizeTrapArgs(D, Args);
 263   SanitizerMask InvalidTrappingKinds = TrappingKinds & NotAllowedWithTrap;
 264
 265   MinimalRuntime =
 266       Args.hasFlag(options::OPT_fsanitize_minimal_runtime,
 267                    options::OPT_fno_sanitize_minimal_runtime, MinimalRuntime);
 268
 269   // The object size sanitizer should not be enabled at -O0.
 270   Arg *OptLevel = Args.getLastArg(options::OPT_O_Group);
 271   bool RemoveObjectSizeAtO0 =
 272       !OptLevel || OptLevel->getOption().matches(options::OPT_O0);
 273
 274   for (ArgList::const_reverse_iterator I = Args.rbegin(), E = Args.rend();
 275        I != E; ++I) {
 276     const auto *Arg = *I;
 277     if (Arg->getOption().matches(options::OPT_fsanitize_EQ)) {
 278       Arg->claim();
 279       SanitizerMask Add = parseArgValues(D, Arg, /*AllowGroups=*/true);
 280
 281       if (RemoveObjectSizeAtO0) {
 282         AllRemove |= SanitizerKind::ObjectSize;
 283
 284         // The user explicitly enabled the object size sanitizer. Warn
 285         // that this does nothing at -O0.
 286         if (Add & SanitizerKind::ObjectSize)
 287           D.Diag(diag::warn_drv_object_size_disabled_O0)
 288               << Arg->getAsString(Args);
 289       }
 290
 291       AllAddedKinds |= expandSanitizerGroups(Add);
 292
 293       // Avoid diagnosing any sanitizer which is disabled later.
 294       Add &= ~AllRemove;
 295       // At this point we have not expanded groups, so any unsupported
 296       // sanitizers in Add are those which have been explicitly enabled.
 297       // Diagnose them.
 298       if (SanitizerMask KindsToDiagnose =
 299               Add & InvalidTrappingKinds & ~DiagnosedKinds) {
 300         std::string Desc = describeSanitizeArg(*I, KindsToDiagnose);
 301         D.Diag(diag::err_drv_argument_not_allowed_with)
 302             << Desc << "-fsanitize-trap=undefined";
 303         DiagnosedKinds |= KindsToDiagnose;
 304       }
 305       Add &= ~InvalidTrappingKinds;
 306
 307       if (MinimalRuntime) {
 308         if (SanitizerMask KindsToDiagnose =
 309                 Add & NotAllowedWithMinimalRuntime & ~DiagnosedKinds) {
 310           std::string Desc = describeSanitizeArg(*I, KindsToDiagnose);
 311           D.Diag(diag::err_drv_argument_not_allowed_with)
 312               << Desc << "-fsanitize-minimal-runtime";
 313           DiagnosedKinds |= KindsToDiagnose;
 314         }
 315         Add &= ~NotAllowedWithMinimalRuntime;
 316       }
 317
 318       // FIXME: Make CFI on member function calls compatible with cross-DSO CFI.
 319       // There are currently two problems:
 320       // - Virtual function call checks need to pass a pointer to the function
 321       //   address to llvm.type.test and a pointer to the address point to the
 322       //   diagnostic function. Currently we pass the same pointer to both
 323       //   places.
 324       // - Non-virtual function call checks may need to check multiple type
 325       //   identifiers.
 326       // Fixing both of those may require changes to the cross-DSO CFI
 327       // interface.
 328       if (CfiCrossDso && (Add & SanitizerKind::CFIMFCall & ~DiagnosedKinds)) {
 329         D.Diag(diag::err_drv_argument_not_allowed_with)
 330             << "-fsanitize=cfi-mfcall"
 331             << "-fsanitize-cfi-cross-dso";
 332         Add &= ~SanitizerKind::CFIMFCall;
 333         DiagnosedKinds |= SanitizerKind::CFIMFCall;
 334       }
 335
 336       if (SanitizerMask KindsToDiagnose = Add & ~Supported & ~DiagnosedKinds) {
 337         std::string Desc = describeSanitizeArg(*I, KindsToDiagnose);
 338         D.Diag(diag::err_drv_unsupported_opt_for_target)
 339             << Desc << TC.getTriple().str();
 340         DiagnosedKinds |= KindsToDiagnose;
 341       }
 342       Add &= Supported;
 343
 344       // Test for -fno-rtti + explicit -fsanitizer=vptr before expanding groups
 345       // so we don't error out if -fno-rtti and -fsanitize=undefined were
 346       // passed.
 347       if ((Add & SanitizerKind::Vptr) && (RTTIMode == ToolChain::RM_Disabled)) {
 348         if (const llvm::opt::Arg *NoRTTIArg = TC.getRTTIArg()) {
 349           assert(NoRTTIArg->getOption().matches(options::OPT_fno_rtti) &&
 350                   "RTTI disabled without -fno-rtti option?");
 351           // The user explicitly passed -fno-rtti with -fsanitize=vptr, but
 352           // the vptr sanitizer requires RTTI, so this is a user error.
 353           D.Diag(diag::err_drv_argument_not_allowed_with)
 354               << "-fsanitize=vptr" << NoRTTIArg->getAsString(Args);
 355         } else {
 356           // The vptr sanitizer requires RTTI, but RTTI is disabled (by
 357           // default). Warn that the vptr sanitizer is being disabled.
 358           D.Diag(diag::warn_drv_disabling_vptr_no_rtti_default);
 359         }
 360
 361         // Take out the Vptr sanitizer from the enabled sanitizers
 362         AllRemove |= SanitizerKind::Vptr;
 363       }
 364
 365       Add = expandSanitizerGroups(Add);
 366       // Group expansion may have enabled a sanitizer which is disabled later.
 367       Add &= ~AllRemove;
 368       // Silently discard any unsupported sanitizers implicitly enabled through
 369       // group expansion.
 370       Add &= ~InvalidTrappingKinds;
 371       if (MinimalRuntime) {
 372         Add &= ~NotAllowedWithMinimalRuntime;
 373       }
 374       if (CfiCrossDso)
 375         Add &= ~SanitizerKind::CFIMFCall;
 376       Add &= Supported;
 377
 378       if (Add & SanitizerKind::Fuzzer)
 379         Add |= SanitizerKind::FuzzerNoLink;
 380
 381       // Enable coverage if the fuzzing flag is set.
 382       if (Add & SanitizerKind::FuzzerNoLink) {
 383         CoverageFeatures |= CoverageInline8bitCounters | CoverageIndirCall |
 384                             CoverageTraceCmp | CoveragePCTable;
 385         // Due to TLS differences, stack depth tracking is only enabled on Linux
 386         if (TC.getTriple().isOSLinux())
 387           CoverageFeatures |= CoverageStackDepth;
 388       }
 389
 390       Kinds |= Add;
 391     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_EQ)) {
 392       Arg->claim();
 393       SanitizerMask Remove = parseArgValues(D, Arg, true);
 394       AllRemove |= expandSanitizerGroups(Remove);
 395     }
 396   }
 397
 398   std::pair<SanitizerMask, SanitizerMask> IncompatibleGroups[] = {
 399       std::make_pair(SanitizerKind::Address,
 400                      SanitizerKind::Thread | SanitizerKind::Memory),
 401       std::make_pair(SanitizerKind::Thread, SanitizerKind::Memory),
 402       std::make_pair(SanitizerKind::Leak,
 403                      SanitizerKind::Thread | SanitizerKind::Memory),
 404       std::make_pair(SanitizerKind::KernelAddress,
 405                      SanitizerKind::Address | SanitizerKind::Leak |
 406                          SanitizerKind::Thread | SanitizerKind::Memory),
 407       std::make_pair(SanitizerKind::HWAddress,
 408                      SanitizerKind::Address | SanitizerKind::Thread |
 409                          SanitizerKind::Memory | SanitizerKind::KernelAddress),
 410       std::make_pair(SanitizerKind::Scudo,
 411                      SanitizerKind::Address | SanitizerKind::HWAddress |
 412                          SanitizerKind::Leak | SanitizerKind::Thread |
 413                          SanitizerKind::Memory | SanitizerKind::KernelAddress),
 414       std::make_pair(SanitizerKind::SafeStack,
 415                      SanitizerKind::Address | SanitizerKind::HWAddress |
 416                          SanitizerKind::Leak | SanitizerKind::Thread |
 417                          SanitizerKind::Memory | SanitizerKind::KernelAddress),
 418       std::make_pair(SanitizerKind::KernelHWAddress,
 419                      SanitizerKind::Address | SanitizerKind::HWAddress |
 420                          SanitizerKind::Leak | SanitizerKind::Thread |
 421                          SanitizerKind::Memory | SanitizerKind::KernelAddress |
 422                          SanitizerKind::SafeStack),
 423       std::make_pair(SanitizerKind::KernelMemory,
 424                      SanitizerKind::Address | SanitizerKind::HWAddress |
 425                          SanitizerKind::Leak | SanitizerKind::Thread |
 426                          SanitizerKind::Memory | SanitizerKind::KernelAddress |
 427                          SanitizerKind::Scudo | SanitizerKind::SafeStack),
 428       std::make_pair(SanitizerKind::MemTag,
 429                      SanitizerKind::Address | SanitizerKind::KernelAddress |
 430                          SanitizerKind::HWAddress |
 431                          SanitizerKind::KernelHWAddress)};
 432   // Enable toolchain specific default sanitizers if not explicitly disabled.
 433   SanitizerMask Default = TC.getDefaultSanitizers() & ~AllRemove;
 434
 435   // Disable default sanitizers that are incompatible with explicitly requested
 436   // ones.
 437   for (auto G : IncompatibleGroups) {
 438     SanitizerMask Group = G.first;
 439     if ((Default & Group) && (Kinds & G.second))
 440       Default &= ~Group;
 441   }
 442
 443   Kinds |= Default;
 444
 445   // We disable the vptr sanitizer if it was enabled by group expansion but RTTI
 446   // is disabled.
 447   if ((Kinds & SanitizerKind::Vptr) && (RTTIMode == ToolChain::RM_Disabled)) {
 448     Kinds &= ~SanitizerKind::Vptr;
 449   }
 450
 451   // Check that LTO is enabled if we need it.
 452   if ((Kinds & NeedsLTO) && !D.isUsingLTO()) {
 453     D.Diag(diag::err_drv_argument_only_allowed_with)
 454         << lastArgumentForMask(D, Args, Kinds & NeedsLTO) << "-flto";
 455   }
 456
 457   if ((Kinds & SanitizerKind::ShadowCallStack) &&
 458       TC.getTriple().getArch() == llvm::Triple::aarch64 &&
 459       !llvm::AArch64::isX18ReservedByDefault(TC.getTriple()) &&
 460       !Args.hasArg(options::OPT_ffixed_x18)) {
 461     D.Diag(diag::err_drv_argument_only_allowed_with)
 462         << lastArgumentForMask(D, Args, Kinds & SanitizerKind::ShadowCallStack)
 463         << "-ffixed-x18";
 464   }
 465
 466   // Report error if there are non-trapping sanitizers that require
 467   // c++abi-specific  parts of UBSan runtime, and they are not provided by the
 468   // toolchain. We don't have a good way to check the latter, so we just
 469   // check if the toolchan supports vptr.
 470   if (~Supported & SanitizerKind::Vptr) {
 471     SanitizerMask KindsToDiagnose = Kinds & ~TrappingKinds & NeedsUbsanCxxRt;
 472     // The runtime library supports the Microsoft C++ ABI, but only well enough
 473     // for CFI. FIXME: Remove this once we support vptr on Windows.
 474     if (TC.getTriple().isOSWindows())
 475       KindsToDiagnose &= ~SanitizerKind::CFI;
 476     if (KindsToDiagnose) {
 477       SanitizerSet S;
 478       S.Mask = KindsToDiagnose;
 479       D.Diag(diag::err_drv_unsupported_opt_for_target)
 480           << ("-fno-sanitize-trap=" + toString(S)) << TC.getTriple().str();
 481       Kinds &= ~KindsToDiagnose;
 482     }
 483   }
 484
 485   // Warn about incompatible groups of sanitizers.
 486   for (auto G : IncompatibleGroups) {
 487     SanitizerMask Group = G.first;
 488     if (Kinds & Group) {
 489       if (SanitizerMask Incompatible = Kinds & G.second) {
 490         D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 491             << lastArgumentForMask(D, Args, Group)
 492             << lastArgumentForMask(D, Args, Incompatible);
 493         Kinds &= ~Incompatible;
 494       }
 495     }
 496   }
 497   // FIXME: Currently -fsanitize=leak is silently ignored in the presence of
 498   // -fsanitize=address. Perhaps it should print an error, or perhaps
 499   // -f(-no)sanitize=leak should change whether leak detection is enabled by
 500   // default in ASan?
 501
 502   // Parse -f(no-)?sanitize-recover flags.
 503   SanitizerMask RecoverableKinds = RecoverableByDefault | AlwaysRecoverable;
 504   SanitizerMask DiagnosedUnrecoverableKinds;
 505   SanitizerMask DiagnosedAlwaysRecoverableKinds;
 506   for (const auto *Arg : Args) {
 507     const char *DeprecatedReplacement = nullptr;
 508     if (Arg->getOption().matches(options::OPT_fsanitize_recover)) {
 509       DeprecatedReplacement =
 510           "-fsanitize-recover=undefined,integer' or '-fsanitize-recover=all";
 511       RecoverableKinds |= expandSanitizerGroups(LegacyFsanitizeRecoverMask);
 512       Arg->claim();
 513     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_recover)) {
 514       DeprecatedReplacement = "-fno-sanitize-recover=undefined,integer' or "
 515                               "'-fno-sanitize-recover=all";
 516       RecoverableKinds &= ~expandSanitizerGroups(LegacyFsanitizeRecoverMask);
 517       Arg->claim();
 518     } else if (Arg->getOption().matches(options::OPT_fsanitize_recover_EQ)) {
 519       SanitizerMask Add = parseArgValues(D, Arg, true);
 520       // Report error if user explicitly tries to recover from unrecoverable
 521       // sanitizer.
 522       if (SanitizerMask KindsToDiagnose =
 523               Add & Unrecoverable & ~DiagnosedUnrecoverableKinds) {
 524         SanitizerSet SetToDiagnose;
 525         SetToDiagnose.Mask |= KindsToDiagnose;
 526         D.Diag(diag::err_drv_unsupported_option_argument)
 527             << Arg->getOption().getName() << toString(SetToDiagnose);
 528         DiagnosedUnrecoverableKinds |= KindsToDiagnose;
 529       }
 530       RecoverableKinds |= expandSanitizerGroups(Add);
 531       Arg->claim();
 532     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_recover_EQ)) {
 533       SanitizerMask Remove = parseArgValues(D, Arg, true);
 534       // Report error if user explicitly tries to disable recovery from
 535       // always recoverable sanitizer.
 536       if (SanitizerMask KindsToDiagnose =
 537               Remove & AlwaysRecoverable & ~DiagnosedAlwaysRecoverableKinds) {
 538         SanitizerSet SetToDiagnose;
 539         SetToDiagnose.Mask |= KindsToDiagnose;
 540         D.Diag(diag::err_drv_unsupported_option_argument)
 541             << Arg->getOption().getName() << toString(SetToDiagnose);
 542         DiagnosedAlwaysRecoverableKinds |= KindsToDiagnose;
 543       }
 544       RecoverableKinds &= ~expandSanitizerGroups(Remove);
 545       Arg->claim();
 546     }
 547     if (DeprecatedReplacement) {
 548       D.Diag(diag::warn_drv_deprecated_arg) << Arg->getAsString(Args)
 549                                             << DeprecatedReplacement;
 550     }
 551   }
 552   RecoverableKinds &= Kinds;
 553   RecoverableKinds &= ~Unrecoverable;
 554
 555   TrappingKinds &= Kinds;
 556   RecoverableKinds &= ~TrappingKinds;
 557
 558   // Setup blacklist files.
 559   // Add default blacklist from resource directory.
 560   addDefaultBlacklists(D, Kinds, BlacklistFiles);
 561   // Parse -f(no-)sanitize-blacklist options.
 562   for (const auto *Arg : Args) {
 563     if (Arg->getOption().matches(options::OPT_fsanitize_blacklist)) {
 564       Arg->claim();
 565       std::string BLPath = Arg->getValue();
 566       if (llvm::sys::fs::exists(BLPath)) {
 567         BlacklistFiles.push_back(BLPath);
 568         ExtraDeps.push_back(BLPath);
 569       } else {
 570         D.Diag(clang::diag::err_drv_no_such_file) << BLPath;
 571       }
 572     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_blacklist)) {
 573       Arg->claim();
 574       BlacklistFiles.clear();
 575       ExtraDeps.clear();
 576     }
 577   }
 578   // Validate blacklists format.
 579   {
 580     std::string BLError;
 581     std::unique_ptr<llvm::SpecialCaseList> SCL(
 582         llvm::SpecialCaseList::create(BlacklistFiles, BLError));
 583     if (!SCL.get())
 584       D.Diag(clang::diag::err_drv_malformed_sanitizer_blacklist) << BLError;
 585   }
 586
 587   // Parse -f[no-]sanitize-memory-track-origins[=level] options.
 588   if (AllAddedKinds & SanitizerKind::Memory) {
 589     if (Arg *A =
 590             Args.getLastArg(options::OPT_fsanitize_memory_track_origins_EQ,
 591                             options::OPT_fsanitize_memory_track_origins,
 592                             options::OPT_fno_sanitize_memory_track_origins)) {
 593       if (A->getOption().matches(options::OPT_fsanitize_memory_track_origins)) {
 594         MsanTrackOrigins = 2;
 595       } else if (A->getOption().matches(
 596                      options::OPT_fno_sanitize_memory_track_origins)) {
 597         MsanTrackOrigins = 0;
 598       } else {
 599         StringRef S = A->getValue();
 600         if (S.getAsInteger(0, MsanTrackOrigins) || MsanTrackOrigins < 0 ||
 601             MsanTrackOrigins > 2) {
 602           D.Diag(clang::diag::err_drv_invalid_value) << A->getAsString(Args) << S;
 603         }
 604       }
 605     }
 606     MsanUseAfterDtor =
 607         Args.hasFlag(options::OPT_fsanitize_memory_use_after_dtor,
 608                      options::OPT_fno_sanitize_memory_use_after_dtor,
 609                      MsanUseAfterDtor);
 610     NeedPIE |= !(TC.getTriple().isOSLinux() &&
 611                  TC.getTriple().getArch() == llvm::Triple::x86_64);
 612   } else {
 613     MsanUseAfterDtor = false;
 614   }
 615
 616   if (AllAddedKinds & SanitizerKind::Thread) {
 617     TsanMemoryAccess = Args.hasFlag(
 618         options::OPT_fsanitize_thread_memory_access,
 619         options::OPT_fno_sanitize_thread_memory_access, TsanMemoryAccess);
 620     TsanFuncEntryExit = Args.hasFlag(
 621         options::OPT_fsanitize_thread_func_entry_exit,
 622         options::OPT_fno_sanitize_thread_func_entry_exit, TsanFuncEntryExit);
 623     TsanAtomics =
 624         Args.hasFlag(options::OPT_fsanitize_thread_atomics,
 625                      options::OPT_fno_sanitize_thread_atomics, TsanAtomics);
 626   }
 627
 628   if (AllAddedKinds & SanitizerKind::CFI) {
 629     // Without PIE, external function address may resolve to a PLT record, which
 630     // can not be verified by the target module.
 631     NeedPIE |= CfiCrossDso;
 632     CfiICallGeneralizePointers =
 633         Args.hasArg(options::OPT_fsanitize_cfi_icall_generalize_pointers);
 634
 635     if (CfiCrossDso && CfiICallGeneralizePointers)
 636       D.Diag(diag::err_drv_argument_not_allowed_with)
 637           << "-fsanitize-cfi-cross-dso"
 638           << "-fsanitize-cfi-icall-generalize-pointers";
 639
 640     CfiCanonicalJumpTables =
 641         Args.hasFlag(options::OPT_fsanitize_cfi_canonical_jump_tables,
 642                      options::OPT_fno_sanitize_cfi_canonical_jump_tables, true);
 643   }
 644
 645   Stats = Args.hasFlag(options::OPT_fsanitize_stats,
 646                        options::OPT_fno_sanitize_stats, false);
 647
 648   if (MinimalRuntime) {
 649     SanitizerMask IncompatibleMask =
 650         Kinds & ~setGroupBits(CompatibleWithMinimalRuntime);
 651     if (IncompatibleMask)
 652       D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 653           << "-fsanitize-minimal-runtime"
 654           << lastArgumentForMask(D, Args, IncompatibleMask);
 655
 656     SanitizerMask NonTrappingCfi = Kinds & SanitizerKind::CFI & ~TrappingKinds;
 657     if (NonTrappingCfi)
 658       D.Diag(clang::diag::err_drv_argument_only_allowed_with)
 659           << "fsanitize-minimal-runtime"
 660           << "fsanitize-trap=cfi";
 661   }
 662
 663   // Parse -f(no-)?sanitize-coverage flags if coverage is supported by the
 664   // enabled sanitizers.
 665   for (const auto *Arg : Args) {
 666     if (Arg->getOption().matches(options::OPT_fsanitize_coverage)) {
 667       int LegacySanitizeCoverage;
 668       if (Arg->getNumValues() == 1 &&
 669           !StringRef(Arg->getValue(0))
 670                .getAsInteger(0, LegacySanitizeCoverage)) {
 671         CoverageFeatures = 0;
 672         Arg->claim();
 673         if (LegacySanitizeCoverage != 0) {
 674           D.Diag(diag::warn_drv_deprecated_arg)
 675               << Arg->getAsString(Args) << "-fsanitize-coverage=trace-pc-guard";
 676         }
 677         continue;
 678       }
 679       CoverageFeatures |= parseCoverageFeatures(D, Arg);
 680
 681       // Disable coverage and not claim the flags if there is at least one
 682       // non-supporting sanitizer.
 683       if (!(AllAddedKinds & ~AllRemove & ~setGroupBits(SupportsCoverage))) {
 684         Arg->claim();
 685       } else {
 686         CoverageFeatures = 0;
 687       }
 688     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_coverage)) {
 689       Arg->claim();
 690       CoverageFeatures &= ~parseCoverageFeatures(D, Arg);
 691     }
 692   }
 693   // Choose at most one coverage type: function, bb, or edge.
 694   if ((CoverageFeatures & CoverageFunc) && (CoverageFeatures & CoverageBB))
 695     D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 696         << "-fsanitize-coverage=func"
 697         << "-fsanitize-coverage=bb";
 698   if ((CoverageFeatures & CoverageFunc) && (CoverageFeatures & CoverageEdge))
 699     D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 700         << "-fsanitize-coverage=func"
 701         << "-fsanitize-coverage=edge";
 702   if ((CoverageFeatures & CoverageBB) && (CoverageFeatures & CoverageEdge))
 703     D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 704         << "-fsanitize-coverage=bb"
 705         << "-fsanitize-coverage=edge";
 706   // Basic block tracing and 8-bit counters require some type of coverage
 707   // enabled.
 708   if (CoverageFeatures & CoverageTraceBB)
 709     D.Diag(clang::diag::warn_drv_deprecated_arg)
 710         << "-fsanitize-coverage=trace-bb"
 711         << "-fsanitize-coverage=trace-pc-guard";
 712   if (CoverageFeatures & Coverage8bitCounters)
 713     D.Diag(clang::diag::warn_drv_deprecated_arg)
 714         << "-fsanitize-coverage=8bit-counters"
 715         << "-fsanitize-coverage=trace-pc-guard";
 716
 717   int InsertionPointTypes = CoverageFunc | CoverageBB | CoverageEdge;
 718   int InstrumentationTypes =
 719       CoverageTracePC | CoverageTracePCGuard | CoverageInline8bitCounters;
 720   if ((CoverageFeatures & InsertionPointTypes) &&
 721       !(CoverageFeatures & InstrumentationTypes)) {
 722     D.Diag(clang::diag::warn_drv_deprecated_arg)
 723         << "-fsanitize-coverage=[func|bb|edge]"
 724         << "-fsanitize-coverage=[func|bb|edge],[trace-pc-guard|trace-pc]";
 725   }
 726
 727   // trace-pc w/o func/bb/edge implies edge.
 728   if (!(CoverageFeatures & InsertionPointTypes)) {
 729     if (CoverageFeatures &
 730         (CoverageTracePC | CoverageTracePCGuard | CoverageInline8bitCounters))
 731       CoverageFeatures |= CoverageEdge;
 732
 733     if (CoverageFeatures & CoverageStackDepth)
 734       CoverageFeatures |= CoverageFunc;
 735   }
 736
 737   SharedRuntime =
 738       Args.hasFlag(options::OPT_shared_libsan, options::OPT_static_libsan,
 739                    TC.getTriple().isAndroid() || TC.getTriple().isOSFuchsia() ||
 740                        TC.getTriple().isOSDarwin());
 741
 742   ImplicitCfiRuntime = TC.getTriple().isAndroid();
 743
 744   if (AllAddedKinds & SanitizerKind::Address) {
 745     NeedPIE |= TC.getTriple().isOSFuchsia();
 746     if (Arg *A =
 747             Args.getLastArg(options::OPT_fsanitize_address_field_padding)) {
 748         StringRef S = A->getValue();
 749         // Legal values are 0 and 1, 2, but in future we may add more levels.
 750         if (S.getAsInteger(0, AsanFieldPadding) || AsanFieldPadding < 0 ||
 751             AsanFieldPadding > 2) {
 752           D.Diag(clang::diag::err_drv_invalid_value) << A->getAsString(Args) << S;
 753         }
 754     }
 755
 756     if (Arg *WindowsDebugRTArg =
 757             Args.getLastArg(options::OPT__SLASH_MTd, options::OPT__SLASH_MT,
 758                             options::OPT__SLASH_MDd, options::OPT__SLASH_MD,
 759                             options::OPT__SLASH_LDd, options::OPT__SLASH_LD)) {
 760       switch (WindowsDebugRTArg->getOption().getID()) {
 761       case options::OPT__SLASH_MTd:
 762       case options::OPT__SLASH_MDd:
 763       case options::OPT__SLASH_LDd:
 764         D.Diag(clang::diag::err_drv_argument_not_allowed_with)
 765             << WindowsDebugRTArg->getAsString(Args)
 766             << lastArgumentForMask(D, Args, SanitizerKind::Address);
 767         D.Diag(clang::diag::note_drv_address_sanitizer_debug_runtime);
 768       }
 769     }
 770
 771     AsanUseAfterScope = Args.hasFlag(
 772         options::OPT_fsanitize_address_use_after_scope,
 773         options::OPT_fno_sanitize_address_use_after_scope, AsanUseAfterScope);
 774
 775     AsanPoisonCustomArrayCookie = Args.hasFlag(
 776         options::OPT_fsanitize_address_poison_custom_array_cookie,
 777         options::OPT_fno_sanitize_address_poison_custom_array_cookie,
 778         AsanPoisonCustomArrayCookie);
 779
 780     // As a workaround for a bug in gold 2.26 and earlier, dead stripping of
 781     // globals in ASan is disabled by default on ELF targets.
 782     // See https://sourceware.org/bugzilla/show_bug.cgi?id=19002
 783     AsanGlobalsDeadStripping =
 784         !TC.getTriple().isOSBinFormatELF() || TC.getTriple().isOSFuchsia() ||
 785         TC.getTriple().isPS4() ||
 786         Args.hasArg(options::OPT_fsanitize_address_globals_dead_stripping);
 787
 788     AsanUseOdrIndicator =
 789         Args.hasFlag(options::OPT_fsanitize_address_use_odr_indicator,
 790                      options::OPT_fno_sanitize_address_use_odr_indicator,
 791                      AsanUseOdrIndicator);
 792
 793     if (AllAddedKinds & SanitizerKind::PointerCompare & ~AllRemove) {
 794       AsanInvalidPointerCmp = true;
 795     }
 796
 797     if (AllAddedKinds & SanitizerKind::PointerSubtract & ~AllRemove) {
 798       AsanInvalidPointerSub = true;
 799     }
 800
 801   } else {
 802     AsanUseAfterScope = false;
 803     // -fsanitize=pointer-compare/pointer-subtract requires -fsanitize=address.
 804     SanitizerMask DetectInvalidPointerPairs =
 805         SanitizerKind::PointerCompare | SanitizerKind::PointerSubtract;
 806     if (AllAddedKinds & DetectInvalidPointerPairs & ~AllRemove) {
 807       TC.getDriver().Diag(clang::diag::err_drv_argument_only_allowed_with)
 808           << lastArgumentForMask(D, Args,
 809                                  SanitizerKind::PointerCompare |
 810                                      SanitizerKind::PointerSubtract)
 811           << "-fsanitize=address";
 812     }
 813   }
 814
 815   if (AllAddedKinds & SanitizerKind::HWAddress) {
 816     if (Arg *HwasanAbiArg =
 817             Args.getLastArg(options::OPT_fsanitize_hwaddress_abi_EQ)) {
 818       HwasanAbi = HwasanAbiArg->getValue();
 819       if (HwasanAbi != "platform" && HwasanAbi != "interceptor")
 820         D.Diag(clang::diag::err_drv_invalid_value)
 821             << HwasanAbiArg->getAsString(Args) << HwasanAbi;
 822     } else {
 823       HwasanAbi = "interceptor";
 824     }
 825   }
 826
 827   if (AllAddedKinds & SanitizerKind::SafeStack) {
 828     // SafeStack runtime is built into the system on Fuchsia.
 829     SafeStackRuntime = !TC.getTriple().isOSFuchsia();
 830   }
 831
 832   LinkRuntimes =
 833       Args.hasFlag(options::OPT_fsanitize_link_runtime,
 834                    options::OPT_fno_sanitize_link_runtime, LinkRuntimes);
 835
 836   // Parse -link-cxx-sanitizer flag.
 837   LinkCXXRuntimes = Args.hasArg(options::OPT_fsanitize_link_cxx_runtime,
 838                                 options::OPT_fno_sanitize_link_cxx_runtime,
 839                                 LinkCXXRuntimes) ||
 840                     D.CCCIsCXX();
 841
 842   // Finally, initialize the set of available and recoverable sanitizers.
 843   Sanitizers.Mask |= Kinds;
 844   RecoverableSanitizers.Mask |= RecoverableKinds;
 845   TrapSanitizers.Mask |= TrappingKinds;
 846   assert(!(RecoverableKinds & TrappingKinds) &&
 847          "Overlap between recoverable and trapping sanitizers");
 848 }
 849
 850 static std::string toString(const clang::SanitizerSet &Sanitizers) {
 851   std::string Res;
 852 #define SANITIZER(NAME, ID)                                                    \
 853   if (Sanitizers.has(SanitizerKind::ID)) {                                     \
 854     if (!Res.empty())                                                          \
 855       Res += ",";                                                              \
 856     Res += NAME;                                                               \
 857   }
 858 #include "clang/Basic/Sanitizers.def"
 859   return Res;
 860 }
 861
 862 static void addIncludeLinkerOption(const ToolChain &TC,
 863                                    const llvm::opt::ArgList &Args,
 864                                    llvm::opt::ArgStringList &CmdArgs,
 865                                    StringRef SymbolName) {
 866   SmallString<64> LinkerOptionFlag;
 867   LinkerOptionFlag = "--linker-option=/include:";
 868   if (TC.getTriple().getArch() == llvm::Triple::x86) {
 869     // Win32 mangles C function names with a '_' prefix.
 870     LinkerOptionFlag += '_';
 871   }
 872   LinkerOptionFlag += SymbolName;
 873   CmdArgs.push_back(Args.MakeArgString(LinkerOptionFlag));
 874 }
 875
 876 static bool hasTargetFeatureMTE(const llvm::opt::ArgStringList &CmdArgs) {
 877   for (auto Start = CmdArgs.begin(), End = CmdArgs.end(); Start != End; ++Start) {
 878     auto It = std::find(Start, End, StringRef("+mte"));
 879     if (It == End)
 880       break;
 881     if (It > Start && *std::prev(It) == StringRef("-target-feature"))
 882       return true;
 883     Start = It;
 884   }
 885   return false;
 886 }
 887
 888 void SanitizerArgs::addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
 889                             llvm::opt::ArgStringList &CmdArgs,
 890                             types::ID InputType) const {
 891   // NVPTX doesn't currently support sanitizers.  Bailing out here means that
 892   // e.g. -fsanitize=address applies only to host code, which is what we want
 893   // for now.
 894   if (TC.getTriple().isNVPTX())
 895     return;
 896
 897   // Translate available CoverageFeatures to corresponding clang-cc1 flags.
 898   // Do it even if Sanitizers.empty() since some forms of coverage don't require
 899   // sanitizers.
 900   std::pair<int, const char *> CoverageFlags[] = {
 901     std::make_pair(CoverageFunc, "-fsanitize-coverage-type=1"),
 902     std::make_pair(CoverageBB, "-fsanitize-coverage-type=2"),
 903     std::make_pair(CoverageEdge, "-fsanitize-coverage-type=3"),
 904     std::make_pair(CoverageIndirCall, "-fsanitize-coverage-indirect-calls"),
 905     std::make_pair(CoverageTraceBB, "-fsanitize-coverage-trace-bb"),
 906     std::make_pair(CoverageTraceCmp, "-fsanitize-coverage-trace-cmp"),
 907     std::make_pair(CoverageTraceDiv, "-fsanitize-coverage-trace-div"),
 908     std::make_pair(CoverageTraceGep, "-fsanitize-coverage-trace-gep"),
 909     std::make_pair(Coverage8bitCounters, "-fsanitize-coverage-8bit-counters"),
 910     std::make_pair(CoverageTracePC, "-fsanitize-coverage-trace-pc"),
 911     std::make_pair(CoverageTracePCGuard, "-fsanitize-coverage-trace-pc-guard"),
 912     std::make_pair(CoverageInline8bitCounters, "-fsanitize-coverage-inline-8bit-counters"),
 913     std::make_pair(CoveragePCTable, "-fsanitize-coverage-pc-table"),
 914     std::make_pair(CoverageNoPrune, "-fsanitize-coverage-no-prune"),
 915     std::make_pair(CoverageStackDepth, "-fsanitize-coverage-stack-depth")};
 916   for (auto F : CoverageFlags) {
 917     if (CoverageFeatures & F.first)
 918       CmdArgs.push_back(F.second);
 919   }
 920
 921   if (TC.getTriple().isOSWindows() && needsUbsanRt()) {
 922     // Instruct the code generator to embed linker directives in the object file
 923     // that cause the required runtime libraries to be linked.
 924     CmdArgs.push_back(Args.MakeArgString(
 925         "--dependent-lib=" + TC.getCompilerRT(Args, "ubsan_standalone")));
 926     if (types::isCXX(InputType))
 927       CmdArgs.push_back(Args.MakeArgString(
 928           "--dependent-lib=" + TC.getCompilerRT(Args, "ubsan_standalone_cxx")));
 929   }
 930   if (TC.getTriple().isOSWindows() && needsStatsRt()) {
 931     CmdArgs.push_back(Args.MakeArgString("--dependent-lib=" +
 932                                          TC.getCompilerRT(Args, "stats_client")));
 933
 934     // The main executable must export the stats runtime.
 935     // FIXME: Only exporting from the main executable (e.g. based on whether the
 936     // translation unit defines main()) would save a little space, but having
 937     // multiple copies of the runtime shouldn't hurt.
 938     CmdArgs.push_back(Args.MakeArgString("--dependent-lib=" +
 939                                          TC.getCompilerRT(Args, "stats")));
 940     addIncludeLinkerOption(TC, Args, CmdArgs, "__sanitizer_stats_register");
 941   }
 942
 943   if (Sanitizers.empty())
 944     return;
 945   CmdArgs.push_back(Args.MakeArgString("-fsanitize=" + toString(Sanitizers)));
 946
 947   if (!RecoverableSanitizers.empty())
 948     CmdArgs.push_back(Args.MakeArgString("-fsanitize-recover=" +
 949                                          toString(RecoverableSanitizers)));
 950
 951   if (!TrapSanitizers.empty())
 952     CmdArgs.push_back(
 953         Args.MakeArgString("-fsanitize-trap=" + toString(TrapSanitizers)));
 954
 955   for (const auto &BLPath : BlacklistFiles) {
 956     SmallString<64> BlacklistOpt("-fsanitize-blacklist=");
 957     BlacklistOpt += BLPath;
 958     CmdArgs.push_back(Args.MakeArgString(BlacklistOpt));
 959   }
 960   for (const auto &Dep : ExtraDeps) {
 961     SmallString<64> ExtraDepOpt("-fdepfile-entry=");
 962     ExtraDepOpt += Dep;
 963     CmdArgs.push_back(Args.MakeArgString(ExtraDepOpt));
 964   }
 965
 966   if (MsanTrackOrigins)
 967     CmdArgs.push_back(Args.MakeArgString("-fsanitize-memory-track-origins=" +
 968                                          Twine(MsanTrackOrigins)));
 969
 970   if (MsanUseAfterDtor)
 971     CmdArgs.push_back("-fsanitize-memory-use-after-dtor");
 972
 973   // FIXME: Pass these parameters as function attributes, not as -llvm flags.
 974   if (!TsanMemoryAccess) {
 975     CmdArgs.push_back("-mllvm");
 976     CmdArgs.push_back("-tsan-instrument-memory-accesses=0");
 977     CmdArgs.push_back("-mllvm");
 978     CmdArgs.push_back("-tsan-instrument-memintrinsics=0");
 979   }
 980   if (!TsanFuncEntryExit) {
 981     CmdArgs.push_back("-mllvm");
 982     CmdArgs.push_back("-tsan-instrument-func-entry-exit=0");
 983   }
 984   if (!TsanAtomics) {
 985     CmdArgs.push_back("-mllvm");
 986     CmdArgs.push_back("-tsan-instrument-atomics=0");
 987   }
 988
 989   if (CfiCrossDso)
 990     CmdArgs.push_back("-fsanitize-cfi-cross-dso");
 991
 992   if (CfiICallGeneralizePointers)
 993     CmdArgs.push_back("-fsanitize-cfi-icall-generalize-pointers");
 994
 995   if (CfiCanonicalJumpTables)
 996     CmdArgs.push_back("-fsanitize-cfi-canonical-jump-tables");
 997
 998   if (Stats)
 999     CmdArgs.push_back("-fsanitize-stats");
1000
1001   if (MinimalRuntime)
1002     CmdArgs.push_back("-fsanitize-minimal-runtime");
1003
1004   if (AsanFieldPadding)
1005     CmdArgs.push_back(Args.MakeArgString("-fsanitize-address-field-padding=" +
1006                                          Twine(AsanFieldPadding)));
1007
1008   if (AsanUseAfterScope)
1009     CmdArgs.push_back("-fsanitize-address-use-after-scope");
1010
1011   if (AsanPoisonCustomArrayCookie)
1012     CmdArgs.push_back("-fsanitize-address-poison-custom-array-cookie");
1013
1014   if (AsanGlobalsDeadStripping)
1015     CmdArgs.push_back("-fsanitize-address-globals-dead-stripping");
1016
1017   if (AsanUseOdrIndicator)
1018     CmdArgs.push_back("-fsanitize-address-use-odr-indicator");
1019
1020   if (AsanInvalidPointerCmp) {
1021     CmdArgs.push_back("-mllvm");
1022     CmdArgs.push_back("-asan-detect-invalid-pointer-cmp");
1023   }
1024
1025   if (AsanInvalidPointerSub) {
1026     CmdArgs.push_back("-mllvm");
1027     CmdArgs.push_back("-asan-detect-invalid-pointer-sub");
1028   }
1029
1030   if (!HwasanAbi.empty()) {
1031     CmdArgs.push_back("-default-function-attr");
1032     CmdArgs.push_back(Args.MakeArgString("hwasan-abi=" + HwasanAbi));
1033   }
1034
1035   if (Sanitizers.has(SanitizerKind::HWAddress)) {
1036     CmdArgs.push_back("-target-feature");
1037     CmdArgs.push_back("+tagged-globals");
1038   }
1039
1040   // MSan: Workaround for PR16386.
1041   // ASan: This is mainly to help LSan with cases such as
1042   // https://github.com/google/sanitizers/issues/373
1043   // We can't make this conditional on -fsanitize=leak, as that flag shouldn't
1044   // affect compilation.
1045   if (Sanitizers.has(SanitizerKind::Memory) ||
1046       Sanitizers.has(SanitizerKind::Address))
1047     CmdArgs.push_back("-fno-assume-sane-operator-new");
1048
1049   // Require -fvisibility= flag on non-Windows when compiling if vptr CFI is
1050   // enabled.
1051   if (Sanitizers.hasOneOf(CFIClasses) && !TC.getTriple().isOSWindows() &&
1052       !Args.hasArg(options::OPT_fvisibility_EQ)) {
1053     TC.getDriver().Diag(clang::diag::err_drv_argument_only_allowed_with)
1054         << lastArgumentForMask(TC.getDriver(), Args,
1055                                Sanitizers.Mask & CFIClasses)
1056         << "-fvisibility=";
1057   }
1058
1059   if (Sanitizers.has(SanitizerKind::MemTag) && !hasTargetFeatureMTE(CmdArgs))
1060     TC.getDriver().Diag(diag::err_stack_tagging_requires_hardware_feature);
1061 }
1062
1063 SanitizerMask parseArgValues(const Driver &D, const llvm::opt::Arg *A,
1064                              bool DiagnoseErrors) {
1065   assert((A->getOption().matches(options::OPT_fsanitize_EQ) ||
1066           A->getOption().matches(options::OPT_fno_sanitize_EQ) ||
1067           A->getOption().matches(options::OPT_fsanitize_recover_EQ) ||
1068           A->getOption().matches(options::OPT_fno_sanitize_recover_EQ) ||
1069           A->getOption().matches(options::OPT_fsanitize_trap_EQ) ||
1070           A->getOption().matches(options::OPT_fno_sanitize_trap_EQ)) &&
1071          "Invalid argument in parseArgValues!");
1072   SanitizerMask Kinds;
1073   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
1074     const char *Value = A->getValue(i);
1075     SanitizerMask Kind;
1076     // Special case: don't accept -fsanitize=all.
1077     if (A->getOption().matches(options::OPT_fsanitize_EQ) &&
1078         0 == strcmp("all", Value))
1079       Kind = SanitizerMask();
1080     else
1081       Kind = parseSanitizerValue(Value, /*AllowGroups=*/true);
1082
1083     if (Kind)
1084       Kinds |= Kind;
1085     else if (DiagnoseErrors)
1086       D.Diag(clang::diag::err_drv_unsupported_option_argument)
1087           << A->getOption().getName() << Value;
1088   }
1089   return Kinds;
1090 }
1091
1092 int parseCoverageFeatures(const Driver &D, const llvm::opt::Arg *A) {
1093   assert(A->getOption().matches(options::OPT_fsanitize_coverage) ||
1094          A->getOption().matches(options::OPT_fno_sanitize_coverage));
1095   int Features = 0;
1096   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
1097     const char *Value = A->getValue(i);
1098     int F = llvm::StringSwitch<int>(Value)
1099         .Case("func", CoverageFunc)
1100         .Case("bb", CoverageBB)
1101         .Case("edge", CoverageEdge)
1102         .Case("indirect-calls", CoverageIndirCall)
1103         .Case("trace-bb", CoverageTraceBB)
1104         .Case("trace-cmp", CoverageTraceCmp)
1105         .Case("trace-div", CoverageTraceDiv)
1106         .Case("trace-gep", CoverageTraceGep)
1107         .Case("8bit-counters", Coverage8bitCounters)
1108         .Case("trace-pc", CoverageTracePC)
1109         .Case("trace-pc-guard", CoverageTracePCGuard)
1110         .Case("no-prune", CoverageNoPrune)
1111         .Case("inline-8bit-counters", CoverageInline8bitCounters)
1112         .Case("pc-table", CoveragePCTable)
1113         .Case("stack-depth", CoverageStackDepth)
1114         .Default(0);
1115     if (F == 0)
1116       D.Diag(clang::diag::err_drv_unsupported_option_argument)
1117           << A->getOption().getName() << Value;
1118     Features |= F;
1119   }
1120   return Features;
1121 }
1122
1123 std::string lastArgumentForMask(const Driver &D, const llvm::opt::ArgList &Args,
1124                                 SanitizerMask Mask) {
1125   for (llvm::opt::ArgList::const_reverse_iterator I = Args.rbegin(),
1126                                                   E = Args.rend();
1127        I != E; ++I) {
1128     const auto *Arg = *I;
1129     if (Arg->getOption().matches(options::OPT_fsanitize_EQ)) {
1130       SanitizerMask AddKinds =
1131           expandSanitizerGroups(parseArgValues(D, Arg, false));
1132       if (AddKinds & Mask)
1133         return describeSanitizeArg(Arg, Mask);
1134     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_EQ)) {
1135       SanitizerMask RemoveKinds =
1136           expandSanitizerGroups(parseArgValues(D, Arg, false));
1137       Mask &= ~RemoveKinds;
1138     }
1139   }
1140   llvm_unreachable("arg list didn't provide expected value");
1141 }
1142
1143 std::string describeSanitizeArg(const llvm::opt::Arg *A, SanitizerMask Mask) {
1144   assert(A->getOption().matches(options::OPT_fsanitize_EQ)
1145          && "Invalid argument in describeSanitizerArg!");
1146
1147   std::string Sanitizers;
1148   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
1149     if (expandSanitizerGroups(
1150             parseSanitizerValue(A->getValue(i), /*AllowGroups=*/true)) &
1151         Mask) {
1152       if (!Sanitizers.empty())
1153         Sanitizers += ",";
1154       Sanitizers += A->getValue(i);
1155     }
1156   }
1157
1158   assert(!Sanitizers.empty() && "arg didn't provide expected value");
1159   return "-fsanitize=" + Sanitizers;
1160 }