xref: /freebsd/contrib/llvm-project/clang/lib/Driver/SanitizerArgs.cpp (revision a0ca4af9455b844c5e094fc1b09b1390ffa979fc)
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/StringRef.h"
17 #include "llvm/ADT/StringSwitch.h"
18 #include "llvm/Support/Path.h"
19 #include "llvm/Support/SpecialCaseList.h"
20 #include "llvm/Support/VirtualFileSystem.h"
21 #include "llvm/TargetParser/AArch64TargetParser.h"
22 #include "llvm/TargetParser/RISCVTargetParser.h"
23 #include "llvm/TargetParser/TargetParser.h"
24 #include "llvm/Transforms/Instrumentation/AddressSanitizerOptions.h"
25 #include <memory>
26 
27 using namespace clang;
28 using namespace clang::driver;
29 using namespace llvm::opt;
30 
31 static const SanitizerMask NeedsUbsanRt =
32     SanitizerKind::Undefined | SanitizerKind::Integer |
33     SanitizerKind::ImplicitConversion | SanitizerKind::Nullability |
34     SanitizerKind::CFI | SanitizerKind::FloatDivideByZero |
35     SanitizerKind::ObjCCast;
36 static const SanitizerMask NeedsUbsanCxxRt =
37     SanitizerKind::Vptr | SanitizerKind::CFI;
38 static const SanitizerMask NotAllowedWithTrap = SanitizerKind::Vptr;
39 static const SanitizerMask NotAllowedWithMinimalRuntime = SanitizerKind::Vptr;
40 static const SanitizerMask NotAllowedWithExecuteOnly =
41     SanitizerKind::Function | SanitizerKind::KCFI;
42 static const SanitizerMask NeedsUnwindTables =
43     SanitizerKind::Address | SanitizerKind::HWAddress | SanitizerKind::Thread |
44     SanitizerKind::Memory | SanitizerKind::DataFlow;
45 static const SanitizerMask SupportsCoverage =
46     SanitizerKind::Address | SanitizerKind::HWAddress |
47     SanitizerKind::KernelAddress | SanitizerKind::KernelHWAddress |
48     SanitizerKind::MemtagStack | SanitizerKind::MemtagHeap |
49     SanitizerKind::MemtagGlobals | SanitizerKind::Memory |
50     SanitizerKind::KernelMemory | SanitizerKind::Leak |
51     SanitizerKind::Undefined | SanitizerKind::Integer | SanitizerKind::Bounds |
52     SanitizerKind::ImplicitConversion | SanitizerKind::Nullability |
53     SanitizerKind::DataFlow | SanitizerKind::Fuzzer |
54     SanitizerKind::FuzzerNoLink | SanitizerKind::FloatDivideByZero |
55     SanitizerKind::SafeStack | SanitizerKind::ShadowCallStack |
56     SanitizerKind::Thread | SanitizerKind::ObjCCast | SanitizerKind::KCFI;
57 static const SanitizerMask RecoverableByDefault =
58     SanitizerKind::Undefined | SanitizerKind::Integer |
59     SanitizerKind::ImplicitConversion | SanitizerKind::Nullability |
60     SanitizerKind::FloatDivideByZero | SanitizerKind::ObjCCast;
61 static const SanitizerMask Unrecoverable =
62     SanitizerKind::Unreachable | SanitizerKind::Return;
63 static const SanitizerMask AlwaysRecoverable = SanitizerKind::KernelAddress |
64                                                SanitizerKind::KernelHWAddress |
65                                                SanitizerKind::KCFI;
66 static const SanitizerMask NeedsLTO = SanitizerKind::CFI;
67 static const SanitizerMask TrappingSupported =
68     (SanitizerKind::Undefined & ~SanitizerKind::Vptr) | SanitizerKind::Integer |
69     SanitizerKind::Nullability | SanitizerKind::LocalBounds |
70     SanitizerKind::CFI | SanitizerKind::FloatDivideByZero |
71     SanitizerKind::ObjCCast;
72 static const SanitizerMask TrappingDefault = SanitizerKind::CFI;
73 static const SanitizerMask CFIClasses =
74     SanitizerKind::CFIVCall | SanitizerKind::CFINVCall |
75     SanitizerKind::CFIMFCall | SanitizerKind::CFIDerivedCast |
76     SanitizerKind::CFIUnrelatedCast;
77 static const SanitizerMask CompatibleWithMinimalRuntime =
78     TrappingSupported | SanitizerKind::Scudo | SanitizerKind::ShadowCallStack |
79     SanitizerKind::MemtagStack | SanitizerKind::MemtagHeap |
80     SanitizerKind::MemtagGlobals | SanitizerKind::KCFI;
81 
82 enum CoverageFeature {
83   CoverageFunc = 1 << 0,
84   CoverageBB = 1 << 1,
85   CoverageEdge = 1 << 2,
86   CoverageIndirCall = 1 << 3,
87   CoverageTraceBB = 1 << 4, // Deprecated.
88   CoverageTraceCmp = 1 << 5,
89   CoverageTraceDiv = 1 << 6,
90   CoverageTraceGep = 1 << 7,
91   Coverage8bitCounters = 1 << 8, // Deprecated.
92   CoverageTracePC = 1 << 9,
93   CoverageTracePCGuard = 1 << 10,
94   CoverageNoPrune = 1 << 11,
95   CoverageInline8bitCounters = 1 << 12,
96   CoveragePCTable = 1 << 13,
97   CoverageStackDepth = 1 << 14,
98   CoverageInlineBoolFlag = 1 << 15,
99   CoverageTraceLoads = 1 << 16,
100   CoverageTraceStores = 1 << 17,
101   CoverageControlFlow = 1 << 18,
102 };
103 
104 enum BinaryMetadataFeature {
105   BinaryMetadataCovered = 1 << 0,
106   BinaryMetadataAtomics = 1 << 1,
107   BinaryMetadataUAR = 1 << 2,
108 };
109 
110 /// Parse a -fsanitize= or -fno-sanitize= argument's values, diagnosing any
111 /// invalid components. Returns a SanitizerMask.
112 static SanitizerMask parseArgValues(const Driver &D, const llvm::opt::Arg *A,
113                                     bool DiagnoseErrors);
114 
115 /// Parse -f(no-)?sanitize-coverage= flag values, diagnosing any invalid
116 /// components. Returns OR of members of \c CoverageFeature enumeration.
117 static int parseCoverageFeatures(const Driver &D, const llvm::opt::Arg *A,
118                                  bool DiagnoseErrors);
119 
120 /// Parse -f(no-)?sanitize-metadata= flag values, diagnosing any invalid
121 /// components. Returns OR of members of \c BinaryMetadataFeature enumeration.
122 static int parseBinaryMetadataFeatures(const Driver &D, const llvm::opt::Arg *A,
123                                        bool DiagnoseErrors);
124 
125 /// Produce an argument string from ArgList \p Args, which shows how it
126 /// provides some sanitizer kind from \p Mask. For example, the argument list
127 /// "-fsanitize=thread,vptr -fsanitize=address" with mask \c NeedsUbsanRt
128 /// would produce "-fsanitize=vptr".
129 static std::string lastArgumentForMask(const Driver &D,
130                                        const llvm::opt::ArgList &Args,
131                                        SanitizerMask Mask);
132 
133 /// Produce an argument string from argument \p A, which shows how it provides
134 /// a value in \p Mask. For instance, the argument
135 /// "-fsanitize=address,alignment" with mask \c NeedsUbsanRt would produce
136 /// "-fsanitize=alignment".
137 static std::string describeSanitizeArg(const llvm::opt::Arg *A,
138                                        SanitizerMask Mask);
139 
140 /// Produce a string containing comma-separated names of sanitizers in \p
141 /// Sanitizers set.
142 static std::string toString(const clang::SanitizerSet &Sanitizers);
143 
144 /// Return true if an execute-only target disallows data access to code
145 /// sections.
146 static bool isExecuteOnlyTarget(const llvm::Triple &Triple,
147                                 const llvm::opt::ArgList &Args) {
148   if (Triple.isPS5())
149     return true;
150   return Args.hasFlagNoClaim(options::OPT_mexecute_only,
151                              options::OPT_mno_execute_only, false);
152 }
153 
154 static void validateSpecialCaseListFormat(const Driver &D,
155                                           std::vector<std::string> &SCLFiles,
156                                           unsigned MalformedSCLErrorDiagID,
157                                           bool DiagnoseErrors) {
158   if (SCLFiles.empty())
159     return;
160 
161   std::string BLError;
162   std::unique_ptr<llvm::SpecialCaseList> SCL(
163       llvm::SpecialCaseList::create(SCLFiles, D.getVFS(), BLError));
164   if (!SCL.get() && DiagnoseErrors)
165     D.Diag(MalformedSCLErrorDiagID) << BLError;
166 }
167 
168 static void addDefaultIgnorelists(const Driver &D, SanitizerMask Kinds,
169                                   std::vector<std::string> &IgnorelistFiles,
170                                   bool DiagnoseErrors) {
171   struct Ignorelist {
172     const char *File;
173     SanitizerMask Mask;
174   } Ignorelists[] = {{"asan_ignorelist.txt", SanitizerKind::Address},
175                      {"hwasan_ignorelist.txt", SanitizerKind::HWAddress},
176                      {"memtag_ignorelist.txt", SanitizerKind::MemTag},
177                      {"msan_ignorelist.txt", SanitizerKind::Memory},
178                      {"tsan_ignorelist.txt", SanitizerKind::Thread},
179                      {"dfsan_abilist.txt", SanitizerKind::DataFlow},
180                      {"cfi_ignorelist.txt", SanitizerKind::CFI},
181                      {"ubsan_ignorelist.txt",
182                       SanitizerKind::Undefined | SanitizerKind::Integer |
183                           SanitizerKind::Nullability |
184                           SanitizerKind::FloatDivideByZero}};
185 
186   for (auto BL : Ignorelists) {
187     if (!(Kinds & BL.Mask))
188       continue;
189 
190     clang::SmallString<64> Path(D.ResourceDir);
191     llvm::sys::path::append(Path, "share", BL.File);
192     if (D.getVFS().exists(Path))
193       IgnorelistFiles.push_back(std::string(Path));
194     else if (BL.Mask == SanitizerKind::CFI && DiagnoseErrors)
195       // If cfi_ignorelist.txt cannot be found in the resource dir, driver
196       // should fail.
197       D.Diag(clang::diag::err_drv_missing_sanitizer_ignorelist) << Path;
198   }
199   validateSpecialCaseListFormat(
200       D, IgnorelistFiles, clang::diag::err_drv_malformed_sanitizer_ignorelist,
201       DiagnoseErrors);
202 }
203 
204 /// Parse -f(no-)?sanitize-(coverage-)?(allow|ignore)list argument's values,
205 /// diagnosing any invalid file paths and validating special case list format.
206 static void parseSpecialCaseListArg(const Driver &D,
207                                     const llvm::opt::ArgList &Args,
208                                     std::vector<std::string> &SCLFiles,
209                                     llvm::opt::OptSpecifier SCLOptionID,
210                                     llvm::opt::OptSpecifier NoSCLOptionID,
211                                     unsigned MalformedSCLErrorDiagID,
212                                     bool DiagnoseErrors) {
213   for (const auto *Arg : Args) {
214     // Match -fsanitize-(coverage-)?(allow|ignore)list.
215     if (Arg->getOption().matches(SCLOptionID)) {
216       Arg->claim();
217       std::string SCLPath = Arg->getValue();
218       if (D.getVFS().exists(SCLPath)) {
219         SCLFiles.push_back(SCLPath);
220       } else if (DiagnoseErrors) {
221         D.Diag(clang::diag::err_drv_no_such_file) << SCLPath;
222       }
223       // Match -fno-sanitize-ignorelist.
224     } else if (Arg->getOption().matches(NoSCLOptionID)) {
225       Arg->claim();
226       SCLFiles.clear();
227     }
228   }
229   validateSpecialCaseListFormat(D, SCLFiles, MalformedSCLErrorDiagID,
230                                 DiagnoseErrors);
231 }
232 
233 /// Sets group bits for every group that has at least one representative already
234 /// enabled in \p Kinds.
235 static SanitizerMask setGroupBits(SanitizerMask Kinds) {
236 #define SANITIZER(NAME, ID)
237 #define SANITIZER_GROUP(NAME, ID, ALIAS)                                       \
238   if (Kinds & SanitizerKind::ID)                                               \
239     Kinds |= SanitizerKind::ID##Group;
240 #include "clang/Basic/Sanitizers.def"
241   return Kinds;
242 }
243 
244 static SanitizerMask parseSanitizeTrapArgs(const Driver &D,
245                                            const llvm::opt::ArgList &Args,
246                                            bool DiagnoseErrors) {
247   SanitizerMask TrapRemove; // During the loop below, the accumulated set of
248                             // sanitizers disabled by the current sanitizer
249                             // argument or any argument after it.
250   SanitizerMask TrappingKinds;
251   SanitizerMask TrappingSupportedWithGroups = setGroupBits(TrappingSupported);
252 
253   for (const llvm::opt::Arg *Arg : llvm::reverse(Args)) {
254     if (Arg->getOption().matches(options::OPT_fsanitize_trap_EQ)) {
255       Arg->claim();
256       SanitizerMask Add = parseArgValues(D, Arg, true);
257       Add &= ~TrapRemove;
258       SanitizerMask InvalidValues = Add & ~TrappingSupportedWithGroups;
259       if (InvalidValues && DiagnoseErrors) {
260         SanitizerSet S;
261         S.Mask = InvalidValues;
262         D.Diag(diag::err_drv_unsupported_option_argument)
263             << Arg->getSpelling() << toString(S);
264       }
265       TrappingKinds |= expandSanitizerGroups(Add) & ~TrapRemove;
266     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_trap_EQ)) {
267       Arg->claim();
268       TrapRemove |=
269           expandSanitizerGroups(parseArgValues(D, Arg, DiagnoseErrors));
270     }
271   }
272 
273   // Apply default trapping behavior.
274   TrappingKinds |= TrappingDefault & ~TrapRemove;
275 
276   return TrappingKinds;
277 }
278 
279 bool SanitizerArgs::needsFuzzerInterceptors() const {
280   return needsFuzzer() && !needsAsanRt() && !needsTsanRt() && !needsMsanRt();
281 }
282 
283 bool SanitizerArgs::needsUbsanRt() const {
284   // All of these include ubsan.
285   if (needsAsanRt() || needsMsanRt() || needsHwasanRt() || needsTsanRt() ||
286       needsDfsanRt() || needsLsanRt() || needsCfiDiagRt() ||
287       (needsScudoRt() && !requiresMinimalRuntime()))
288     return false;
289 
290   return (Sanitizers.Mask & NeedsUbsanRt & ~TrapSanitizers.Mask) ||
291          CoverageFeatures;
292 }
293 
294 bool SanitizerArgs::needsCfiRt() const {
295   return !(Sanitizers.Mask & SanitizerKind::CFI & ~TrapSanitizers.Mask) &&
296          CfiCrossDso && !ImplicitCfiRuntime;
297 }
298 
299 bool SanitizerArgs::needsCfiDiagRt() const {
300   return (Sanitizers.Mask & SanitizerKind::CFI & ~TrapSanitizers.Mask) &&
301          CfiCrossDso && !ImplicitCfiRuntime;
302 }
303 
304 bool SanitizerArgs::requiresPIE() const { return NeedPIE; }
305 
306 bool SanitizerArgs::needsUnwindTables() const {
307   return static_cast<bool>(Sanitizers.Mask & NeedsUnwindTables);
308 }
309 
310 bool SanitizerArgs::needsLTO() const {
311   return static_cast<bool>(Sanitizers.Mask & NeedsLTO);
312 }
313 
314 SanitizerArgs::SanitizerArgs(const ToolChain &TC,
315                              const llvm::opt::ArgList &Args,
316                              bool DiagnoseErrors) {
317   SanitizerMask AllRemove;      // During the loop below, the accumulated set of
318                                 // sanitizers disabled by the current sanitizer
319                                 // argument or any argument after it.
320   SanitizerMask AllAddedKinds;  // Mask of all sanitizers ever enabled by
321                                 // -fsanitize= flags (directly or via group
322                                 // expansion), some of which may be disabled
323                                 // later. Used to carefully prune
324                                 // unused-argument diagnostics.
325   SanitizerMask DiagnosedKinds; // All Kinds we have diagnosed up to now.
326                                 // Used to deduplicate diagnostics.
327   SanitizerMask Kinds;
328   const SanitizerMask Supported = setGroupBits(TC.getSupportedSanitizers());
329 
330   CfiCrossDso = Args.hasFlag(options::OPT_fsanitize_cfi_cross_dso,
331                              options::OPT_fno_sanitize_cfi_cross_dso, false);
332 
333   ToolChain::RTTIMode RTTIMode = TC.getRTTIMode();
334 
335   const Driver &D = TC.getDriver();
336   SanitizerMask TrappingKinds = parseSanitizeTrapArgs(D, Args, DiagnoseErrors);
337   SanitizerMask InvalidTrappingKinds = TrappingKinds & NotAllowedWithTrap;
338 
339   MinimalRuntime =
340       Args.hasFlag(options::OPT_fsanitize_minimal_runtime,
341                    options::OPT_fno_sanitize_minimal_runtime, MinimalRuntime);
342 
343   // The object size sanitizer should not be enabled at -O0.
344   Arg *OptLevel = Args.getLastArg(options::OPT_O_Group);
345   bool RemoveObjectSizeAtO0 =
346       !OptLevel || OptLevel->getOption().matches(options::OPT_O0);
347 
348   for (const llvm::opt::Arg *Arg : llvm::reverse(Args)) {
349     if (Arg->getOption().matches(options::OPT_fsanitize_EQ)) {
350       Arg->claim();
351       SanitizerMask Add = parseArgValues(D, Arg, DiagnoseErrors);
352 
353       if (RemoveObjectSizeAtO0) {
354         AllRemove |= SanitizerKind::ObjectSize;
355 
356         // The user explicitly enabled the object size sanitizer. Warn
357         // that this does nothing at -O0.
358         if ((Add & SanitizerKind::ObjectSize) && DiagnoseErrors)
359           D.Diag(diag::warn_drv_object_size_disabled_O0)
360               << Arg->getAsString(Args);
361       }
362 
363       AllAddedKinds |= expandSanitizerGroups(Add);
364 
365       // Avoid diagnosing any sanitizer which is disabled later.
366       Add &= ~AllRemove;
367       // At this point we have not expanded groups, so any unsupported
368       // sanitizers in Add are those which have been explicitly enabled.
369       // Diagnose them.
370       if (SanitizerMask KindsToDiagnose =
371               Add & InvalidTrappingKinds & ~DiagnosedKinds) {
372         if (DiagnoseErrors) {
373           std::string Desc = describeSanitizeArg(Arg, KindsToDiagnose);
374           D.Diag(diag::err_drv_argument_not_allowed_with)
375               << Desc << "-fsanitize-trap=undefined";
376         }
377         DiagnosedKinds |= KindsToDiagnose;
378       }
379       Add &= ~InvalidTrappingKinds;
380 
381       if (MinimalRuntime) {
382         if (SanitizerMask KindsToDiagnose =
383                 Add & NotAllowedWithMinimalRuntime & ~DiagnosedKinds) {
384           if (DiagnoseErrors) {
385             std::string Desc = describeSanitizeArg(Arg, KindsToDiagnose);
386             D.Diag(diag::err_drv_argument_not_allowed_with)
387                 << Desc << "-fsanitize-minimal-runtime";
388           }
389           DiagnosedKinds |= KindsToDiagnose;
390         }
391         Add &= ~NotAllowedWithMinimalRuntime;
392       }
393 
394       if (llvm::opt::Arg *A = Args.getLastArg(options::OPT_mcmodel_EQ)) {
395         StringRef CM = A->getValue();
396         if (CM != "small" &&
397             (Add & SanitizerKind::Function & ~DiagnosedKinds)) {
398           if (DiagnoseErrors)
399             D.Diag(diag::err_drv_argument_only_allowed_with)
400                 << "-fsanitize=function"
401                 << "-mcmodel=small";
402           Add &= ~SanitizerKind::Function;
403           DiagnosedKinds |= SanitizerKind::Function;
404         }
405       }
406       // -fsanitize=function and -fsanitize=kcfi instrument indirect function
407       // calls to load a type hash before the function label. Therefore, an
408       // execute-only target doesn't support the function and kcfi sanitizers.
409       const llvm::Triple &Triple = TC.getTriple();
410       if (isExecuteOnlyTarget(Triple, Args)) {
411         if (SanitizerMask KindsToDiagnose =
412                 Add & NotAllowedWithExecuteOnly & ~DiagnosedKinds) {
413           if (DiagnoseErrors) {
414             std::string Desc = describeSanitizeArg(Arg, KindsToDiagnose);
415             D.Diag(diag::err_drv_argument_not_allowed_with)
416                 << Desc << Triple.str();
417           }
418           DiagnosedKinds |= KindsToDiagnose;
419         }
420         Add &= ~NotAllowedWithExecuteOnly;
421       }
422 
423       // FIXME: Make CFI on member function calls compatible with cross-DSO CFI.
424       // There are currently two problems:
425       // - Virtual function call checks need to pass a pointer to the function
426       //   address to llvm.type.test and a pointer to the address point to the
427       //   diagnostic function. Currently we pass the same pointer to both
428       //   places.
429       // - Non-virtual function call checks may need to check multiple type
430       //   identifiers.
431       // Fixing both of those may require changes to the cross-DSO CFI
432       // interface.
433       if (CfiCrossDso && (Add & SanitizerKind::CFIMFCall & ~DiagnosedKinds)) {
434         if (DiagnoseErrors)
435           D.Diag(diag::err_drv_argument_not_allowed_with)
436               << "-fsanitize=cfi-mfcall"
437               << "-fsanitize-cfi-cross-dso";
438         Add &= ~SanitizerKind::CFIMFCall;
439         DiagnosedKinds |= SanitizerKind::CFIMFCall;
440       }
441 
442       if (SanitizerMask KindsToDiagnose = Add & ~Supported & ~DiagnosedKinds) {
443         if (DiagnoseErrors) {
444           std::string Desc = describeSanitizeArg(Arg, KindsToDiagnose);
445           D.Diag(diag::err_drv_unsupported_opt_for_target)
446               << Desc << TC.getTriple().str();
447         }
448         DiagnosedKinds |= KindsToDiagnose;
449       }
450       Add &= Supported;
451 
452       // Test for -fno-rtti + explicit -fsanitizer=vptr before expanding groups
453       // so we don't error out if -fno-rtti and -fsanitize=undefined were
454       // passed.
455       if ((Add & SanitizerKind::Vptr) && (RTTIMode == ToolChain::RM_Disabled)) {
456         if (const llvm::opt::Arg *NoRTTIArg = TC.getRTTIArg()) {
457           assert(NoRTTIArg->getOption().matches(options::OPT_fno_rtti) &&
458                  "RTTI disabled without -fno-rtti option?");
459           // The user explicitly passed -fno-rtti with -fsanitize=vptr, but
460           // the vptr sanitizer requires RTTI, so this is a user error.
461           if (DiagnoseErrors)
462             D.Diag(diag::err_drv_argument_not_allowed_with)
463                 << "-fsanitize=vptr" << NoRTTIArg->getAsString(Args);
464         } else {
465           // The vptr sanitizer requires RTTI, but RTTI is disabled (by
466           // default). Warn that the vptr sanitizer is being disabled.
467           if (DiagnoseErrors)
468             D.Diag(diag::warn_drv_disabling_vptr_no_rtti_default);
469         }
470 
471         // Take out the Vptr sanitizer from the enabled sanitizers
472         AllRemove |= SanitizerKind::Vptr;
473       }
474 
475       Add = expandSanitizerGroups(Add);
476       // Group expansion may have enabled a sanitizer which is disabled later.
477       Add &= ~AllRemove;
478       // Silently discard any unsupported sanitizers implicitly enabled through
479       // group expansion.
480       Add &= ~InvalidTrappingKinds;
481       if (MinimalRuntime) {
482         Add &= ~NotAllowedWithMinimalRuntime;
483       }
484       // NotAllowedWithExecuteOnly is silently discarded on an execute-only
485       // target if implicitly enabled through group expansion.
486       if (isExecuteOnlyTarget(Triple, Args))
487         Add &= ~NotAllowedWithExecuteOnly;
488       if (CfiCrossDso)
489         Add &= ~SanitizerKind::CFIMFCall;
490       Add &= Supported;
491 
492       if (Add & SanitizerKind::Fuzzer)
493         Add |= SanitizerKind::FuzzerNoLink;
494 
495       // Enable coverage if the fuzzing flag is set.
496       if (Add & SanitizerKind::FuzzerNoLink) {
497         CoverageFeatures |= CoverageInline8bitCounters | CoverageIndirCall |
498                             CoverageTraceCmp | CoveragePCTable;
499         // Due to TLS differences, stack depth tracking is only enabled on Linux
500         if (TC.getTriple().isOSLinux())
501           CoverageFeatures |= CoverageStackDepth;
502       }
503 
504       Kinds |= Add;
505     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_EQ)) {
506       Arg->claim();
507       SanitizerMask Remove = parseArgValues(D, Arg, DiagnoseErrors);
508       AllRemove |= expandSanitizerGroups(Remove);
509     }
510   }
511 
512   std::pair<SanitizerMask, SanitizerMask> IncompatibleGroups[] = {
513       std::make_pair(SanitizerKind::Address,
514                      SanitizerKind::Thread | SanitizerKind::Memory),
515       std::make_pair(SanitizerKind::Thread, SanitizerKind::Memory),
516       std::make_pair(SanitizerKind::Leak,
517                      SanitizerKind::Thread | SanitizerKind::Memory),
518       std::make_pair(SanitizerKind::KernelAddress,
519                      SanitizerKind::Address | SanitizerKind::Leak |
520                          SanitizerKind::Thread | SanitizerKind::Memory),
521       std::make_pair(SanitizerKind::HWAddress,
522                      SanitizerKind::Address | SanitizerKind::Thread |
523                          SanitizerKind::Memory | SanitizerKind::KernelAddress),
524       std::make_pair(SanitizerKind::Scudo,
525                      SanitizerKind::Address | SanitizerKind::HWAddress |
526                          SanitizerKind::Leak | SanitizerKind::Thread |
527                          SanitizerKind::Memory | SanitizerKind::KernelAddress),
528       std::make_pair(SanitizerKind::SafeStack,
529                      (TC.getTriple().isOSFuchsia() ? SanitizerMask()
530                                                    : SanitizerKind::Leak) |
531                          SanitizerKind::Address | SanitizerKind::HWAddress |
532                          SanitizerKind::Thread | SanitizerKind::Memory |
533                          SanitizerKind::KernelAddress),
534       std::make_pair(SanitizerKind::KernelHWAddress,
535                      SanitizerKind::Address | SanitizerKind::HWAddress |
536                          SanitizerKind::Leak | SanitizerKind::Thread |
537                          SanitizerKind::Memory | SanitizerKind::KernelAddress |
538                          SanitizerKind::SafeStack),
539       std::make_pair(SanitizerKind::KernelMemory,
540                      SanitizerKind::Address | SanitizerKind::HWAddress |
541                          SanitizerKind::Leak | SanitizerKind::Thread |
542                          SanitizerKind::Memory | SanitizerKind::KernelAddress |
543                          SanitizerKind::Scudo | SanitizerKind::SafeStack),
544       std::make_pair(SanitizerKind::MemTag,
545                      SanitizerKind::Address | SanitizerKind::KernelAddress |
546                          SanitizerKind::HWAddress |
547                          SanitizerKind::KernelHWAddress),
548       std::make_pair(SanitizerKind::KCFI, SanitizerKind::Function)};
549   // Enable toolchain specific default sanitizers if not explicitly disabled.
550   SanitizerMask Default = TC.getDefaultSanitizers() & ~AllRemove;
551 
552   // Disable default sanitizers that are incompatible with explicitly requested
553   // ones.
554   for (auto G : IncompatibleGroups) {
555     SanitizerMask Group = G.first;
556     if ((Default & Group) && (Kinds & G.second))
557       Default &= ~Group;
558   }
559 
560   Kinds |= Default;
561 
562   // We disable the vptr sanitizer if it was enabled by group expansion but RTTI
563   // is disabled.
564   if ((Kinds & SanitizerKind::Vptr) && (RTTIMode == ToolChain::RM_Disabled)) {
565     Kinds &= ~SanitizerKind::Vptr;
566   }
567 
568   // Check that LTO is enabled if we need it.
569   if ((Kinds & NeedsLTO) && !D.isUsingLTO() && DiagnoseErrors) {
570     D.Diag(diag::err_drv_argument_only_allowed_with)
571         << lastArgumentForMask(D, Args, Kinds & NeedsLTO) << "-flto";
572   }
573 
574   if ((Kinds & SanitizerKind::ShadowCallStack) && TC.getTriple().isAArch64() &&
575       !llvm::AArch64::isX18ReservedByDefault(TC.getTriple()) &&
576       !Args.hasArg(options::OPT_ffixed_x18) && DiagnoseErrors) {
577     D.Diag(diag::err_drv_argument_only_allowed_with)
578         << lastArgumentForMask(D, Args, Kinds & SanitizerKind::ShadowCallStack)
579         << "-ffixed-x18";
580   }
581 
582   // Report error if there are non-trapping sanitizers that require
583   // c++abi-specific  parts of UBSan runtime, and they are not provided by the
584   // toolchain. We don't have a good way to check the latter, so we just
585   // check if the toolchan supports vptr.
586   if (~Supported & SanitizerKind::Vptr) {
587     SanitizerMask KindsToDiagnose = Kinds & ~TrappingKinds & NeedsUbsanCxxRt;
588     // The runtime library supports the Microsoft C++ ABI, but only well enough
589     // for CFI. FIXME: Remove this once we support vptr on Windows.
590     if (TC.getTriple().isOSWindows())
591       KindsToDiagnose &= ~SanitizerKind::CFI;
592     if (KindsToDiagnose) {
593       SanitizerSet S;
594       S.Mask = KindsToDiagnose;
595       if (DiagnoseErrors)
596         D.Diag(diag::err_drv_unsupported_opt_for_target)
597             << ("-fno-sanitize-trap=" + toString(S)) << TC.getTriple().str();
598       Kinds &= ~KindsToDiagnose;
599     }
600   }
601 
602   // Warn about incompatible groups of sanitizers.
603   for (auto G : IncompatibleGroups) {
604     SanitizerMask Group = G.first;
605     if (Kinds & Group) {
606       if (SanitizerMask Incompatible = Kinds & G.second) {
607         if (DiagnoseErrors)
608           D.Diag(clang::diag::err_drv_argument_not_allowed_with)
609               << lastArgumentForMask(D, Args, Group)
610               << lastArgumentForMask(D, Args, Incompatible);
611         Kinds &= ~Incompatible;
612       }
613     }
614   }
615   // FIXME: Currently -fsanitize=leak is silently ignored in the presence of
616   // -fsanitize=address. Perhaps it should print an error, or perhaps
617   // -f(-no)sanitize=leak should change whether leak detection is enabled by
618   // default in ASan?
619 
620   // Parse -f(no-)?sanitize-recover flags.
621   SanitizerMask RecoverableKinds = RecoverableByDefault | AlwaysRecoverable;
622   SanitizerMask DiagnosedUnrecoverableKinds;
623   SanitizerMask DiagnosedAlwaysRecoverableKinds;
624   for (const auto *Arg : Args) {
625     if (Arg->getOption().matches(options::OPT_fsanitize_recover_EQ)) {
626       SanitizerMask Add = parseArgValues(D, Arg, DiagnoseErrors);
627       // Report error if user explicitly tries to recover from unrecoverable
628       // sanitizer.
629       if (SanitizerMask KindsToDiagnose =
630               Add & Unrecoverable & ~DiagnosedUnrecoverableKinds) {
631         SanitizerSet SetToDiagnose;
632         SetToDiagnose.Mask |= KindsToDiagnose;
633         if (DiagnoseErrors)
634           D.Diag(diag::err_drv_unsupported_option_argument)
635               << Arg->getSpelling() << toString(SetToDiagnose);
636         DiagnosedUnrecoverableKinds |= KindsToDiagnose;
637       }
638       RecoverableKinds |= expandSanitizerGroups(Add);
639       Arg->claim();
640     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_recover_EQ)) {
641       SanitizerMask Remove = parseArgValues(D, Arg, DiagnoseErrors);
642       // Report error if user explicitly tries to disable recovery from
643       // always recoverable sanitizer.
644       if (SanitizerMask KindsToDiagnose =
645               Remove & AlwaysRecoverable & ~DiagnosedAlwaysRecoverableKinds) {
646         SanitizerSet SetToDiagnose;
647         SetToDiagnose.Mask |= KindsToDiagnose;
648         if (DiagnoseErrors)
649           D.Diag(diag::err_drv_unsupported_option_argument)
650               << Arg->getSpelling() << toString(SetToDiagnose);
651         DiagnosedAlwaysRecoverableKinds |= KindsToDiagnose;
652       }
653       RecoverableKinds &= ~expandSanitizerGroups(Remove);
654       Arg->claim();
655     }
656   }
657   RecoverableKinds &= Kinds;
658   RecoverableKinds &= ~Unrecoverable;
659 
660   TrappingKinds &= Kinds;
661   RecoverableKinds &= ~TrappingKinds;
662 
663   // Setup ignorelist files.
664   // Add default ignorelist from resource directory for activated sanitizers,
665   // and validate special case lists format.
666   if (!Args.hasArgNoClaim(options::OPT_fno_sanitize_ignorelist))
667     addDefaultIgnorelists(D, Kinds, SystemIgnorelistFiles, DiagnoseErrors);
668 
669   // Parse -f(no-)?sanitize-ignorelist options.
670   // This also validates special case lists format.
671   parseSpecialCaseListArg(
672       D, Args, UserIgnorelistFiles, options::OPT_fsanitize_ignorelist_EQ,
673       options::OPT_fno_sanitize_ignorelist,
674       clang::diag::err_drv_malformed_sanitizer_ignorelist, DiagnoseErrors);
675 
676   // Parse -f[no-]sanitize-memory-track-origins[=level] options.
677   if (AllAddedKinds & SanitizerKind::Memory) {
678     if (Arg *A =
679             Args.getLastArg(options::OPT_fsanitize_memory_track_origins_EQ,
680                             options::OPT_fno_sanitize_memory_track_origins)) {
681       if (!A->getOption().matches(
682               options::OPT_fno_sanitize_memory_track_origins)) {
683         StringRef S = A->getValue();
684         if (S.getAsInteger(0, MsanTrackOrigins) || MsanTrackOrigins < 0 ||
685             MsanTrackOrigins > 2) {
686           if (DiagnoseErrors)
687             D.Diag(clang::diag::err_drv_invalid_value)
688                 << A->getAsString(Args) << S;
689         }
690       }
691     }
692     MsanUseAfterDtor = Args.hasFlag(
693         options::OPT_fsanitize_memory_use_after_dtor,
694         options::OPT_fno_sanitize_memory_use_after_dtor, MsanUseAfterDtor);
695     MsanParamRetval = Args.hasFlag(
696         options::OPT_fsanitize_memory_param_retval,
697         options::OPT_fno_sanitize_memory_param_retval, MsanParamRetval);
698   } else if (AllAddedKinds & SanitizerKind::KernelMemory) {
699     MsanUseAfterDtor = false;
700     MsanParamRetval = Args.hasFlag(
701         options::OPT_fsanitize_memory_param_retval,
702         options::OPT_fno_sanitize_memory_param_retval, MsanParamRetval);
703   } else {
704     MsanUseAfterDtor = false;
705     MsanParamRetval = false;
706   }
707 
708   if (AllAddedKinds & SanitizerKind::MemTag) {
709     StringRef S =
710         Args.getLastArgValue(options::OPT_fsanitize_memtag_mode_EQ, "sync");
711     if (S == "async" || S == "sync") {
712       MemtagMode = S.str();
713     } else {
714       D.Diag(clang::diag::err_drv_invalid_value_with_suggestion)
715           << "-fsanitize-memtag-mode=" << S << "{async, sync}";
716       MemtagMode = "sync";
717     }
718   }
719 
720   if (AllAddedKinds & SanitizerKind::Thread) {
721     TsanMemoryAccess = Args.hasFlag(
722         options::OPT_fsanitize_thread_memory_access,
723         options::OPT_fno_sanitize_thread_memory_access, TsanMemoryAccess);
724     TsanFuncEntryExit = Args.hasFlag(
725         options::OPT_fsanitize_thread_func_entry_exit,
726         options::OPT_fno_sanitize_thread_func_entry_exit, TsanFuncEntryExit);
727     TsanAtomics =
728         Args.hasFlag(options::OPT_fsanitize_thread_atomics,
729                      options::OPT_fno_sanitize_thread_atomics, TsanAtomics);
730   }
731 
732   if (AllAddedKinds & SanitizerKind::CFI) {
733     // Without PIE, external function address may resolve to a PLT record, which
734     // can not be verified by the target module.
735     NeedPIE |= CfiCrossDso;
736     CfiICallGeneralizePointers =
737         Args.hasArg(options::OPT_fsanitize_cfi_icall_generalize_pointers);
738 
739     CfiICallNormalizeIntegers =
740         Args.hasArg(options::OPT_fsanitize_cfi_icall_normalize_integers);
741 
742     if (CfiCrossDso && CfiICallGeneralizePointers && DiagnoseErrors)
743       D.Diag(diag::err_drv_argument_not_allowed_with)
744           << "-fsanitize-cfi-cross-dso"
745           << "-fsanitize-cfi-icall-generalize-pointers";
746 
747     CfiCanonicalJumpTables =
748         Args.hasFlag(options::OPT_fsanitize_cfi_canonical_jump_tables,
749                      options::OPT_fno_sanitize_cfi_canonical_jump_tables, true);
750   }
751 
752   if (AllAddedKinds & SanitizerKind::KCFI) {
753     CfiICallNormalizeIntegers =
754         Args.hasArg(options::OPT_fsanitize_cfi_icall_normalize_integers);
755 
756     if (AllAddedKinds & SanitizerKind::CFI && DiagnoseErrors)
757       D.Diag(diag::err_drv_argument_not_allowed_with)
758           << "-fsanitize=kcfi"
759           << lastArgumentForMask(D, Args, SanitizerKind::CFI);
760   }
761 
762   Stats = Args.hasFlag(options::OPT_fsanitize_stats,
763                        options::OPT_fno_sanitize_stats, false);
764 
765   if (MinimalRuntime) {
766     SanitizerMask IncompatibleMask =
767         Kinds & ~setGroupBits(CompatibleWithMinimalRuntime);
768     if (IncompatibleMask && DiagnoseErrors)
769       D.Diag(clang::diag::err_drv_argument_not_allowed_with)
770           << "-fsanitize-minimal-runtime"
771           << lastArgumentForMask(D, Args, IncompatibleMask);
772 
773     SanitizerMask NonTrappingCfi = Kinds & SanitizerKind::CFI & ~TrappingKinds;
774     if (NonTrappingCfi && DiagnoseErrors)
775       D.Diag(clang::diag::err_drv_argument_only_allowed_with)
776           << "fsanitize-minimal-runtime"
777           << "fsanitize-trap=cfi";
778   }
779 
780   // Parse -f(no-)?sanitize-coverage flags if coverage is supported by the
781   // enabled sanitizers.
782   for (const auto *Arg : Args) {
783     if (Arg->getOption().matches(options::OPT_fsanitize_coverage)) {
784       int LegacySanitizeCoverage;
785       if (Arg->getNumValues() == 1 &&
786           !StringRef(Arg->getValue(0))
787                .getAsInteger(0, LegacySanitizeCoverage)) {
788         CoverageFeatures = 0;
789         Arg->claim();
790         if (LegacySanitizeCoverage != 0 && DiagnoseErrors) {
791           D.Diag(diag::warn_drv_deprecated_arg)
792               << Arg->getAsString(Args) << "-fsanitize-coverage=trace-pc-guard";
793         }
794         continue;
795       }
796       CoverageFeatures |= parseCoverageFeatures(D, Arg, DiagnoseErrors);
797 
798       // Disable coverage and not claim the flags if there is at least one
799       // non-supporting sanitizer.
800       if (!(AllAddedKinds & ~AllRemove & ~setGroupBits(SupportsCoverage))) {
801         Arg->claim();
802       } else {
803         CoverageFeatures = 0;
804       }
805     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_coverage)) {
806       Arg->claim();
807       CoverageFeatures &= ~parseCoverageFeatures(D, Arg, DiagnoseErrors);
808     }
809   }
810   // Choose at most one coverage type: function, bb, or edge.
811   if (DiagnoseErrors) {
812     if ((CoverageFeatures & CoverageFunc) && (CoverageFeatures & CoverageBB))
813       D.Diag(clang::diag::err_drv_argument_not_allowed_with)
814           << "-fsanitize-coverage=func"
815           << "-fsanitize-coverage=bb";
816     if ((CoverageFeatures & CoverageFunc) && (CoverageFeatures & CoverageEdge))
817       D.Diag(clang::diag::err_drv_argument_not_allowed_with)
818           << "-fsanitize-coverage=func"
819           << "-fsanitize-coverage=edge";
820     if ((CoverageFeatures & CoverageBB) && (CoverageFeatures & CoverageEdge))
821       D.Diag(clang::diag::err_drv_argument_not_allowed_with)
822           << "-fsanitize-coverage=bb"
823           << "-fsanitize-coverage=edge";
824     // Basic block tracing and 8-bit counters require some type of coverage
825     // enabled.
826     if (CoverageFeatures & CoverageTraceBB)
827       D.Diag(clang::diag::warn_drv_deprecated_arg)
828           << "-fsanitize-coverage=trace-bb"
829           << "-fsanitize-coverage=trace-pc-guard";
830     if (CoverageFeatures & Coverage8bitCounters)
831       D.Diag(clang::diag::warn_drv_deprecated_arg)
832           << "-fsanitize-coverage=8bit-counters"
833           << "-fsanitize-coverage=trace-pc-guard";
834   }
835 
836   int InsertionPointTypes = CoverageFunc | CoverageBB | CoverageEdge;
837   int InstrumentationTypes = CoverageTracePC | CoverageTracePCGuard |
838                              CoverageInline8bitCounters | CoverageTraceLoads |
839                              CoverageTraceStores | CoverageInlineBoolFlag |
840                              CoverageControlFlow;
841   if ((CoverageFeatures & InsertionPointTypes) &&
842       !(CoverageFeatures & InstrumentationTypes) && DiagnoseErrors) {
843     D.Diag(clang::diag::warn_drv_deprecated_arg)
844         << "-fsanitize-coverage=[func|bb|edge]"
845         << "-fsanitize-coverage=[func|bb|edge],[trace-pc-guard|trace-pc],["
846            "control-flow]";
847   }
848 
849   // trace-pc w/o func/bb/edge implies edge.
850   if (!(CoverageFeatures & InsertionPointTypes)) {
851     if (CoverageFeatures &
852         (CoverageTracePC | CoverageTracePCGuard | CoverageInline8bitCounters |
853          CoverageInlineBoolFlag | CoverageControlFlow))
854       CoverageFeatures |= CoverageEdge;
855 
856     if (CoverageFeatures & CoverageStackDepth)
857       CoverageFeatures |= CoverageFunc;
858   }
859 
860   // Parse -fsanitize-coverage-(allow|ignore)list options if coverage enabled.
861   // This also validates special case lists format.
862   // Here, OptSpecifier() acts as a never-matching command-line argument.
863   // So, there is no way to clear coverage lists but you can append to them.
864   if (CoverageFeatures) {
865     parseSpecialCaseListArg(
866         D, Args, CoverageAllowlistFiles,
867         options::OPT_fsanitize_coverage_allowlist, OptSpecifier(),
868         clang::diag::err_drv_malformed_sanitizer_coverage_allowlist,
869         DiagnoseErrors);
870     parseSpecialCaseListArg(
871         D, Args, CoverageIgnorelistFiles,
872         options::OPT_fsanitize_coverage_ignorelist, OptSpecifier(),
873         clang::diag::err_drv_malformed_sanitizer_coverage_ignorelist,
874         DiagnoseErrors);
875   }
876 
877   // Parse -f(no-)?sanitize-metadata.
878   for (const auto *Arg :
879        Args.filtered(options::OPT_fexperimental_sanitize_metadata_EQ,
880                      options::OPT_fno_experimental_sanitize_metadata_EQ)) {
881     if (Arg->getOption().matches(
882             options::OPT_fexperimental_sanitize_metadata_EQ)) {
883       Arg->claim();
884       BinaryMetadataFeatures |=
885           parseBinaryMetadataFeatures(D, Arg, DiagnoseErrors);
886     } else {
887       Arg->claim();
888       BinaryMetadataFeatures &=
889           ~parseBinaryMetadataFeatures(D, Arg, DiagnoseErrors);
890     }
891   }
892 
893   // Parse -fsanitize-metadata-ignorelist option if enabled.
894   if (BinaryMetadataFeatures) {
895     parseSpecialCaseListArg(
896         D, Args, BinaryMetadataIgnorelistFiles,
897         options::OPT_fexperimental_sanitize_metadata_ignorelist_EQ,
898         OptSpecifier(), // Cannot clear ignore list, only append.
899         clang::diag::err_drv_malformed_sanitizer_metadata_ignorelist,
900         DiagnoseErrors);
901   }
902 
903   SharedRuntime =
904       Args.hasFlag(options::OPT_shared_libsan, options::OPT_static_libsan,
905                    TC.getTriple().isAndroid() || TC.getTriple().isOSFuchsia() ||
906                        TC.getTriple().isOSDarwin());
907 
908   ImplicitCfiRuntime = TC.getTriple().isAndroid();
909 
910   if (AllAddedKinds & SanitizerKind::Address) {
911     NeedPIE |= TC.getTriple().isOSFuchsia();
912     if (Arg *A =
913             Args.getLastArg(options::OPT_fsanitize_address_field_padding)) {
914       StringRef S = A->getValue();
915       // Legal values are 0 and 1, 2, but in future we may add more levels.
916       if ((S.getAsInteger(0, AsanFieldPadding) || AsanFieldPadding < 0 ||
917            AsanFieldPadding > 2) &&
918           DiagnoseErrors) {
919         D.Diag(clang::diag::err_drv_invalid_value) << A->getAsString(Args) << S;
920       }
921     }
922 
923     if (Arg *WindowsDebugRTArg =
924             Args.getLastArg(options::OPT__SLASH_MTd, options::OPT__SLASH_MT,
925                             options::OPT__SLASH_MDd, options::OPT__SLASH_MD,
926                             options::OPT__SLASH_LDd, options::OPT__SLASH_LD)) {
927       switch (WindowsDebugRTArg->getOption().getID()) {
928       case options::OPT__SLASH_MTd:
929       case options::OPT__SLASH_MDd:
930       case options::OPT__SLASH_LDd:
931         if (DiagnoseErrors) {
932           D.Diag(clang::diag::err_drv_argument_not_allowed_with)
933               << WindowsDebugRTArg->getAsString(Args)
934               << lastArgumentForMask(D, Args, SanitizerKind::Address);
935           D.Diag(clang::diag::note_drv_address_sanitizer_debug_runtime);
936         }
937       }
938     }
939 
940     StableABI = Args.hasFlag(options::OPT_fsanitize_stable_abi,
941                              options::OPT_fno_sanitize_stable_abi, false);
942 
943     AsanUseAfterScope = Args.hasFlag(
944         options::OPT_fsanitize_address_use_after_scope,
945         options::OPT_fno_sanitize_address_use_after_scope, AsanUseAfterScope);
946 
947     AsanPoisonCustomArrayCookie = Args.hasFlag(
948         options::OPT_fsanitize_address_poison_custom_array_cookie,
949         options::OPT_fno_sanitize_address_poison_custom_array_cookie,
950         AsanPoisonCustomArrayCookie);
951 
952     AsanOutlineInstrumentation =
953         Args.hasFlag(options::OPT_fsanitize_address_outline_instrumentation,
954                      options::OPT_fno_sanitize_address_outline_instrumentation,
955                      AsanOutlineInstrumentation);
956 
957     AsanGlobalsDeadStripping = Args.hasFlag(
958         options::OPT_fsanitize_address_globals_dead_stripping,
959         options::OPT_fno_sanitize_address_globals_dead_stripping, true);
960 
961     // Enable ODR indicators which allow better handling of mixed instrumented
962     // and uninstrumented globals. Disable them for Windows where weak odr
963     // indicators (.weak.__odr_asan_gen*) may cause multiple definition linker
964     // errors in the absence of -lldmingw.
965     AsanUseOdrIndicator =
966         Args.hasFlag(options::OPT_fsanitize_address_use_odr_indicator,
967                      options::OPT_fno_sanitize_address_use_odr_indicator,
968                      !TC.getTriple().isOSWindows());
969 
970     if (AllAddedKinds & SanitizerKind::PointerCompare & ~AllRemove) {
971       AsanInvalidPointerCmp = true;
972     }
973 
974     if (AllAddedKinds & SanitizerKind::PointerSubtract & ~AllRemove) {
975       AsanInvalidPointerSub = true;
976     }
977 
978     if (TC.getTriple().isOSDarwin() &&
979         (Args.hasArg(options::OPT_mkernel) ||
980          Args.hasArg(options::OPT_fapple_kext))) {
981       AsanDtorKind = llvm::AsanDtorKind::None;
982     }
983 
984     if (const auto *Arg =
985             Args.getLastArg(options::OPT_sanitize_address_destructor_EQ)) {
986       auto parsedAsanDtorKind = AsanDtorKindFromString(Arg->getValue());
987       if (parsedAsanDtorKind == llvm::AsanDtorKind::Invalid && DiagnoseErrors) {
988         TC.getDriver().Diag(clang::diag::err_drv_unsupported_option_argument)
989             << Arg->getSpelling() << Arg->getValue();
990       }
991       AsanDtorKind = parsedAsanDtorKind;
992     }
993 
994     if (const auto *Arg = Args.getLastArg(
995             options::OPT_sanitize_address_use_after_return_EQ)) {
996       auto parsedAsanUseAfterReturn =
997           AsanDetectStackUseAfterReturnModeFromString(Arg->getValue());
998       if (parsedAsanUseAfterReturn ==
999               llvm::AsanDetectStackUseAfterReturnMode::Invalid &&
1000           DiagnoseErrors) {
1001         TC.getDriver().Diag(clang::diag::err_drv_unsupported_option_argument)
1002             << Arg->getSpelling() << Arg->getValue();
1003       }
1004       AsanUseAfterReturn = parsedAsanUseAfterReturn;
1005     }
1006 
1007   } else {
1008     AsanUseAfterScope = false;
1009     // -fsanitize=pointer-compare/pointer-subtract requires -fsanitize=address.
1010     SanitizerMask DetectInvalidPointerPairs =
1011         SanitizerKind::PointerCompare | SanitizerKind::PointerSubtract;
1012     if ((AllAddedKinds & DetectInvalidPointerPairs & ~AllRemove) &&
1013         DiagnoseErrors) {
1014       TC.getDriver().Diag(clang::diag::err_drv_argument_only_allowed_with)
1015           << lastArgumentForMask(D, Args,
1016                                  SanitizerKind::PointerCompare |
1017                                      SanitizerKind::PointerSubtract)
1018           << "-fsanitize=address";
1019     }
1020   }
1021 
1022   if (AllAddedKinds & SanitizerKind::HWAddress) {
1023     if (Arg *HwasanAbiArg =
1024             Args.getLastArg(options::OPT_fsanitize_hwaddress_abi_EQ)) {
1025       HwasanAbi = HwasanAbiArg->getValue();
1026       if (HwasanAbi != "platform" && HwasanAbi != "interceptor" &&
1027           DiagnoseErrors)
1028         D.Diag(clang::diag::err_drv_invalid_value)
1029             << HwasanAbiArg->getAsString(Args) << HwasanAbi;
1030     } else {
1031       HwasanAbi = "interceptor";
1032     }
1033     if (TC.getTriple().getArch() == llvm::Triple::x86_64)
1034       HwasanUseAliases = Args.hasFlag(
1035           options::OPT_fsanitize_hwaddress_experimental_aliasing,
1036           options::OPT_fno_sanitize_hwaddress_experimental_aliasing,
1037           HwasanUseAliases);
1038   }
1039 
1040   if (AllAddedKinds & SanitizerKind::SafeStack) {
1041     // SafeStack runtime is built into the system on Android and Fuchsia.
1042     SafeStackRuntime =
1043         !TC.getTriple().isAndroid() && !TC.getTriple().isOSFuchsia();
1044   }
1045 
1046   LinkRuntimes =
1047       Args.hasFlag(options::OPT_fsanitize_link_runtime,
1048                    options::OPT_fno_sanitize_link_runtime, LinkRuntimes);
1049 
1050   // Parse -link-cxx-sanitizer flag.
1051   LinkCXXRuntimes = Args.hasArg(options::OPT_fsanitize_link_cxx_runtime,
1052                                 options::OPT_fno_sanitize_link_cxx_runtime,
1053                                 LinkCXXRuntimes) ||
1054                     D.CCCIsCXX();
1055 
1056   NeedsMemProfRt = Args.hasFlag(options::OPT_fmemory_profile,
1057                                 options::OPT_fmemory_profile_EQ,
1058                                 options::OPT_fno_memory_profile, false);
1059 
1060   // Finally, initialize the set of available and recoverable sanitizers.
1061   Sanitizers.Mask |= Kinds;
1062   RecoverableSanitizers.Mask |= RecoverableKinds;
1063   TrapSanitizers.Mask |= TrappingKinds;
1064   assert(!(RecoverableKinds & TrappingKinds) &&
1065          "Overlap between recoverable and trapping sanitizers");
1066 }
1067 
1068 static std::string toString(const clang::SanitizerSet &Sanitizers) {
1069   std::string Res;
1070 #define SANITIZER(NAME, ID)                                                    \
1071   if (Sanitizers.has(SanitizerKind::ID)) {                                     \
1072     if (!Res.empty())                                                          \
1073       Res += ",";                                                              \
1074     Res += NAME;                                                               \
1075   }
1076 #include "clang/Basic/Sanitizers.def"
1077   return Res;
1078 }
1079 
1080 static void addSpecialCaseListOpt(const llvm::opt::ArgList &Args,
1081                                   llvm::opt::ArgStringList &CmdArgs,
1082                                   const char *SCLOptFlag,
1083                                   const std::vector<std::string> &SCLFiles) {
1084   for (const auto &SCLPath : SCLFiles) {
1085     SmallString<64> SCLOpt(SCLOptFlag);
1086     SCLOpt += SCLPath;
1087     CmdArgs.push_back(Args.MakeArgString(SCLOpt));
1088   }
1089 }
1090 
1091 static void addIncludeLinkerOption(const ToolChain &TC,
1092                                    const llvm::opt::ArgList &Args,
1093                                    llvm::opt::ArgStringList &CmdArgs,
1094                                    StringRef SymbolName) {
1095   SmallString<64> LinkerOptionFlag;
1096   LinkerOptionFlag = "--linker-option=/include:";
1097   if (TC.getTriple().getArch() == llvm::Triple::x86) {
1098     // Win32 mangles C function names with a '_' prefix.
1099     LinkerOptionFlag += '_';
1100   }
1101   LinkerOptionFlag += SymbolName;
1102   CmdArgs.push_back(Args.MakeArgString(LinkerOptionFlag));
1103 }
1104 
1105 static bool hasTargetFeatureMTE(const llvm::opt::ArgStringList &CmdArgs) {
1106   for (auto Start = CmdArgs.begin(), End = CmdArgs.end(); Start != End;
1107        ++Start) {
1108     auto It = std::find(Start, End, StringRef("+mte"));
1109     if (It == End)
1110       break;
1111     if (It > Start && *std::prev(It) == StringRef("-target-feature"))
1112       return true;
1113     Start = It;
1114   }
1115   return false;
1116 }
1117 
1118 void SanitizerArgs::addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
1119                             llvm::opt::ArgStringList &CmdArgs,
1120                             types::ID InputType) const {
1121   // NVPTX doesn't currently support sanitizers.  Bailing out here means
1122   // that e.g. -fsanitize=address applies only to host code, which is what we
1123   // want for now.
1124   if (TC.getTriple().isNVPTX())
1125     return;
1126   // AMDGPU sanitizer support is experimental and controlled by -fgpu-sanitize.
1127   bool GPUSanitize = false;
1128   if (TC.getTriple().isAMDGPU()) {
1129     if (!Args.hasFlag(options::OPT_fgpu_sanitize, options::OPT_fno_gpu_sanitize,
1130                       true))
1131       return;
1132     GPUSanitize = true;
1133   }
1134 
1135   // Translate available CoverageFeatures to corresponding clang-cc1 flags.
1136   // Do it even if Sanitizers.empty() since some forms of coverage don't require
1137   // sanitizers.
1138   std::pair<int, const char *> CoverageFlags[] = {
1139       std::make_pair(CoverageFunc, "-fsanitize-coverage-type=1"),
1140       std::make_pair(CoverageBB, "-fsanitize-coverage-type=2"),
1141       std::make_pair(CoverageEdge, "-fsanitize-coverage-type=3"),
1142       std::make_pair(CoverageIndirCall, "-fsanitize-coverage-indirect-calls"),
1143       std::make_pair(CoverageTraceBB, "-fsanitize-coverage-trace-bb"),
1144       std::make_pair(CoverageTraceCmp, "-fsanitize-coverage-trace-cmp"),
1145       std::make_pair(CoverageTraceDiv, "-fsanitize-coverage-trace-div"),
1146       std::make_pair(CoverageTraceGep, "-fsanitize-coverage-trace-gep"),
1147       std::make_pair(Coverage8bitCounters, "-fsanitize-coverage-8bit-counters"),
1148       std::make_pair(CoverageTracePC, "-fsanitize-coverage-trace-pc"),
1149       std::make_pair(CoverageTracePCGuard,
1150                      "-fsanitize-coverage-trace-pc-guard"),
1151       std::make_pair(CoverageInline8bitCounters,
1152                      "-fsanitize-coverage-inline-8bit-counters"),
1153       std::make_pair(CoverageInlineBoolFlag,
1154                      "-fsanitize-coverage-inline-bool-flag"),
1155       std::make_pair(CoveragePCTable, "-fsanitize-coverage-pc-table"),
1156       std::make_pair(CoverageNoPrune, "-fsanitize-coverage-no-prune"),
1157       std::make_pair(CoverageStackDepth, "-fsanitize-coverage-stack-depth"),
1158       std::make_pair(CoverageTraceLoads, "-fsanitize-coverage-trace-loads"),
1159       std::make_pair(CoverageTraceStores, "-fsanitize-coverage-trace-stores"),
1160       std::make_pair(CoverageControlFlow, "-fsanitize-coverage-control-flow")};
1161   for (auto F : CoverageFlags) {
1162     if (CoverageFeatures & F.first)
1163       CmdArgs.push_back(F.second);
1164   }
1165   addSpecialCaseListOpt(
1166       Args, CmdArgs, "-fsanitize-coverage-allowlist=", CoverageAllowlistFiles);
1167   addSpecialCaseListOpt(Args, CmdArgs, "-fsanitize-coverage-ignorelist=",
1168                         CoverageIgnorelistFiles);
1169 
1170   if (!GPUSanitize) {
1171     // Translate available BinaryMetadataFeatures to corresponding clang-cc1
1172     // flags. Does not depend on any other sanitizers. Unsupported on GPUs.
1173     const std::pair<int, std::string> BinaryMetadataFlags[] = {
1174         std::make_pair(BinaryMetadataCovered, "covered"),
1175         std::make_pair(BinaryMetadataAtomics, "atomics"),
1176         std::make_pair(BinaryMetadataUAR, "uar")};
1177     for (const auto &F : BinaryMetadataFlags) {
1178       if (BinaryMetadataFeatures & F.first)
1179         CmdArgs.push_back(
1180             Args.MakeArgString("-fexperimental-sanitize-metadata=" + F.second));
1181     }
1182     addSpecialCaseListOpt(Args, CmdArgs,
1183                           "-fexperimental-sanitize-metadata-ignorelist=",
1184                           BinaryMetadataIgnorelistFiles);
1185   }
1186 
1187   if (TC.getTriple().isOSWindows() && needsUbsanRt()) {
1188     // Instruct the code generator to embed linker directives in the object file
1189     // that cause the required runtime libraries to be linked.
1190     CmdArgs.push_back(
1191         Args.MakeArgString("--dependent-lib=" +
1192                            TC.getCompilerRTBasename(Args, "ubsan_standalone")));
1193     if (types::isCXX(InputType))
1194       CmdArgs.push_back(Args.MakeArgString(
1195           "--dependent-lib=" +
1196           TC.getCompilerRTBasename(Args, "ubsan_standalone_cxx")));
1197   }
1198   if (TC.getTriple().isOSWindows() && needsStatsRt()) {
1199     CmdArgs.push_back(Args.MakeArgString(
1200         "--dependent-lib=" + TC.getCompilerRTBasename(Args, "stats_client")));
1201 
1202     // The main executable must export the stats runtime.
1203     // FIXME: Only exporting from the main executable (e.g. based on whether the
1204     // translation unit defines main()) would save a little space, but having
1205     // multiple copies of the runtime shouldn't hurt.
1206     CmdArgs.push_back(Args.MakeArgString(
1207         "--dependent-lib=" + TC.getCompilerRTBasename(Args, "stats")));
1208     addIncludeLinkerOption(TC, Args, CmdArgs, "__sanitizer_stats_register");
1209   }
1210 
1211   if (Sanitizers.empty())
1212     return;
1213   CmdArgs.push_back(Args.MakeArgString("-fsanitize=" + toString(Sanitizers)));
1214 
1215   if (!RecoverableSanitizers.empty())
1216     CmdArgs.push_back(Args.MakeArgString("-fsanitize-recover=" +
1217                                          toString(RecoverableSanitizers)));
1218 
1219   if (!TrapSanitizers.empty())
1220     CmdArgs.push_back(
1221         Args.MakeArgString("-fsanitize-trap=" + toString(TrapSanitizers)));
1222 
1223   addSpecialCaseListOpt(Args, CmdArgs,
1224                         "-fsanitize-ignorelist=", UserIgnorelistFiles);
1225   addSpecialCaseListOpt(Args, CmdArgs,
1226                         "-fsanitize-system-ignorelist=", SystemIgnorelistFiles);
1227 
1228   if (MsanTrackOrigins)
1229     CmdArgs.push_back(Args.MakeArgString("-fsanitize-memory-track-origins=" +
1230                                          Twine(MsanTrackOrigins)));
1231 
1232   if (MsanUseAfterDtor)
1233     CmdArgs.push_back("-fsanitize-memory-use-after-dtor");
1234 
1235   if (!MsanParamRetval)
1236     CmdArgs.push_back("-fno-sanitize-memory-param-retval");
1237 
1238   // FIXME: Pass these parameters as function attributes, not as -llvm flags.
1239   if (!TsanMemoryAccess) {
1240     CmdArgs.push_back("-mllvm");
1241     CmdArgs.push_back("-tsan-instrument-memory-accesses=0");
1242     CmdArgs.push_back("-mllvm");
1243     CmdArgs.push_back("-tsan-instrument-memintrinsics=0");
1244   }
1245   if (!TsanFuncEntryExit) {
1246     CmdArgs.push_back("-mllvm");
1247     CmdArgs.push_back("-tsan-instrument-func-entry-exit=0");
1248   }
1249   if (!TsanAtomics) {
1250     CmdArgs.push_back("-mllvm");
1251     CmdArgs.push_back("-tsan-instrument-atomics=0");
1252   }
1253 
1254   if (HwasanUseAliases) {
1255     CmdArgs.push_back("-mllvm");
1256     CmdArgs.push_back("-hwasan-experimental-use-page-aliases=1");
1257   }
1258 
1259   if (CfiCrossDso)
1260     CmdArgs.push_back("-fsanitize-cfi-cross-dso");
1261 
1262   if (CfiICallGeneralizePointers)
1263     CmdArgs.push_back("-fsanitize-cfi-icall-generalize-pointers");
1264 
1265   if (CfiICallNormalizeIntegers)
1266     CmdArgs.push_back("-fsanitize-cfi-icall-experimental-normalize-integers");
1267 
1268   if (CfiCanonicalJumpTables)
1269     CmdArgs.push_back("-fsanitize-cfi-canonical-jump-tables");
1270 
1271   if (Stats)
1272     CmdArgs.push_back("-fsanitize-stats");
1273 
1274   if (MinimalRuntime)
1275     CmdArgs.push_back("-fsanitize-minimal-runtime");
1276 
1277   if (AsanFieldPadding)
1278     CmdArgs.push_back(Args.MakeArgString("-fsanitize-address-field-padding=" +
1279                                          Twine(AsanFieldPadding)));
1280 
1281   if (AsanUseAfterScope)
1282     CmdArgs.push_back("-fsanitize-address-use-after-scope");
1283 
1284   if (AsanPoisonCustomArrayCookie)
1285     CmdArgs.push_back("-fsanitize-address-poison-custom-array-cookie");
1286 
1287   if (AsanGlobalsDeadStripping)
1288     CmdArgs.push_back("-fsanitize-address-globals-dead-stripping");
1289 
1290   if (!AsanUseOdrIndicator)
1291     CmdArgs.push_back("-fno-sanitize-address-use-odr-indicator");
1292 
1293   if (AsanInvalidPointerCmp) {
1294     CmdArgs.push_back("-mllvm");
1295     CmdArgs.push_back("-asan-detect-invalid-pointer-cmp");
1296   }
1297 
1298   if (AsanInvalidPointerSub) {
1299     CmdArgs.push_back("-mllvm");
1300     CmdArgs.push_back("-asan-detect-invalid-pointer-sub");
1301   }
1302 
1303   if (AsanOutlineInstrumentation) {
1304     CmdArgs.push_back("-mllvm");
1305     CmdArgs.push_back("-asan-instrumentation-with-call-threshold=0");
1306   }
1307 
1308   // When emitting Stable ABI instrumentation, force outlining calls and avoid
1309   // inlining shadow memory poisoning. While this is a big performance burden
1310   // for now it allows full abstraction from implementation details.
1311   if (StableABI) {
1312     CmdArgs.push_back("-mllvm");
1313     CmdArgs.push_back("-asan-instrumentation-with-call-threshold=0");
1314     CmdArgs.push_back("-mllvm");
1315     CmdArgs.push_back("-asan-max-inline-poisoning-size=0");
1316     CmdArgs.push_back("-mllvm");
1317     CmdArgs.push_back("-asan-guard-against-version-mismatch=0");
1318   }
1319 
1320   // Only pass the option to the frontend if the user requested,
1321   // otherwise the frontend will just use the codegen default.
1322   if (AsanDtorKind != llvm::AsanDtorKind::Invalid) {
1323     CmdArgs.push_back(Args.MakeArgString("-fsanitize-address-destructor=" +
1324                                          AsanDtorKindToString(AsanDtorKind)));
1325   }
1326 
1327   if (AsanUseAfterReturn != llvm::AsanDetectStackUseAfterReturnMode::Invalid) {
1328     CmdArgs.push_back(Args.MakeArgString(
1329         "-fsanitize-address-use-after-return=" +
1330         AsanDetectStackUseAfterReturnModeToString(AsanUseAfterReturn)));
1331   }
1332 
1333   if (!HwasanAbi.empty()) {
1334     CmdArgs.push_back("-default-function-attr");
1335     CmdArgs.push_back(Args.MakeArgString("hwasan-abi=" + HwasanAbi));
1336   }
1337 
1338   if (Sanitizers.has(SanitizerKind::HWAddress) && !HwasanUseAliases) {
1339     CmdArgs.push_back("-target-feature");
1340     CmdArgs.push_back("+tagged-globals");
1341   }
1342 
1343   // MSan: Workaround for PR16386.
1344   // ASan: This is mainly to help LSan with cases such as
1345   // https://github.com/google/sanitizers/issues/373
1346   // We can't make this conditional on -fsanitize=leak, as that flag shouldn't
1347   // affect compilation.
1348   if (Sanitizers.has(SanitizerKind::Memory) ||
1349       Sanitizers.has(SanitizerKind::Address))
1350     CmdArgs.push_back("-fno-assume-sane-operator-new");
1351 
1352   // libFuzzer wants to intercept calls to certain library functions, so the
1353   // following -fno-builtin-* flags force the compiler to emit interposable
1354   // libcalls to these functions. Other sanitizers effectively do the same thing
1355   // by marking all library call sites with NoBuiltin attribute in their LLVM
1356   // pass. (see llvm::maybeMarkSanitizerLibraryCallNoBuiltin)
1357   if (Sanitizers.has(SanitizerKind::FuzzerNoLink)) {
1358     CmdArgs.push_back("-fno-builtin-bcmp");
1359     CmdArgs.push_back("-fno-builtin-memcmp");
1360     CmdArgs.push_back("-fno-builtin-strncmp");
1361     CmdArgs.push_back("-fno-builtin-strcmp");
1362     CmdArgs.push_back("-fno-builtin-strncasecmp");
1363     CmdArgs.push_back("-fno-builtin-strcasecmp");
1364     CmdArgs.push_back("-fno-builtin-strstr");
1365     CmdArgs.push_back("-fno-builtin-strcasestr");
1366     CmdArgs.push_back("-fno-builtin-memmem");
1367   }
1368 
1369   // Require -fvisibility= flag on non-Windows when compiling if vptr CFI is
1370   // enabled.
1371   if (Sanitizers.hasOneOf(CFIClasses) && !TC.getTriple().isOSWindows() &&
1372       !Args.hasArg(options::OPT_fvisibility_EQ)) {
1373     TC.getDriver().Diag(clang::diag::err_drv_argument_only_allowed_with)
1374         << lastArgumentForMask(TC.getDriver(), Args,
1375                                Sanitizers.Mask & CFIClasses)
1376         << "-fvisibility=";
1377   }
1378 
1379   if (Sanitizers.has(SanitizerKind::MemtagStack) &&
1380       !hasTargetFeatureMTE(CmdArgs))
1381     TC.getDriver().Diag(diag::err_stack_tagging_requires_hardware_feature);
1382 }
1383 
1384 SanitizerMask parseArgValues(const Driver &D, const llvm::opt::Arg *A,
1385                              bool DiagnoseErrors) {
1386   assert((A->getOption().matches(options::OPT_fsanitize_EQ) ||
1387           A->getOption().matches(options::OPT_fno_sanitize_EQ) ||
1388           A->getOption().matches(options::OPT_fsanitize_recover_EQ) ||
1389           A->getOption().matches(options::OPT_fno_sanitize_recover_EQ) ||
1390           A->getOption().matches(options::OPT_fsanitize_trap_EQ) ||
1391           A->getOption().matches(options::OPT_fno_sanitize_trap_EQ)) &&
1392          "Invalid argument in parseArgValues!");
1393   SanitizerMask Kinds;
1394   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
1395     const char *Value = A->getValue(i);
1396     SanitizerMask Kind;
1397     // Special case: don't accept -fsanitize=all.
1398     if (A->getOption().matches(options::OPT_fsanitize_EQ) &&
1399         0 == strcmp("all", Value))
1400       Kind = SanitizerMask();
1401     else
1402       Kind = parseSanitizerValue(Value, /*AllowGroups=*/true);
1403 
1404     if (Kind)
1405       Kinds |= Kind;
1406     else if (DiagnoseErrors)
1407       D.Diag(clang::diag::err_drv_unsupported_option_argument)
1408           << A->getSpelling() << Value;
1409   }
1410   return Kinds;
1411 }
1412 
1413 int parseCoverageFeatures(const Driver &D, const llvm::opt::Arg *A,
1414                           bool DiagnoseErrors) {
1415   assert(A->getOption().matches(options::OPT_fsanitize_coverage) ||
1416          A->getOption().matches(options::OPT_fno_sanitize_coverage));
1417   int Features = 0;
1418   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
1419     const char *Value = A->getValue(i);
1420     int F = llvm::StringSwitch<int>(Value)
1421                 .Case("func", CoverageFunc)
1422                 .Case("bb", CoverageBB)
1423                 .Case("edge", CoverageEdge)
1424                 .Case("indirect-calls", CoverageIndirCall)
1425                 .Case("trace-bb", CoverageTraceBB)
1426                 .Case("trace-cmp", CoverageTraceCmp)
1427                 .Case("trace-div", CoverageTraceDiv)
1428                 .Case("trace-gep", CoverageTraceGep)
1429                 .Case("8bit-counters", Coverage8bitCounters)
1430                 .Case("trace-pc", CoverageTracePC)
1431                 .Case("trace-pc-guard", CoverageTracePCGuard)
1432                 .Case("no-prune", CoverageNoPrune)
1433                 .Case("inline-8bit-counters", CoverageInline8bitCounters)
1434                 .Case("inline-bool-flag", CoverageInlineBoolFlag)
1435                 .Case("pc-table", CoveragePCTable)
1436                 .Case("stack-depth", CoverageStackDepth)
1437                 .Case("trace-loads", CoverageTraceLoads)
1438                 .Case("trace-stores", CoverageTraceStores)
1439                 .Case("control-flow", CoverageControlFlow)
1440                 .Default(0);
1441     if (F == 0 && DiagnoseErrors)
1442       D.Diag(clang::diag::err_drv_unsupported_option_argument)
1443           << A->getSpelling() << Value;
1444     Features |= F;
1445   }
1446   return Features;
1447 }
1448 
1449 int parseBinaryMetadataFeatures(const Driver &D, const llvm::opt::Arg *A,
1450                                 bool DiagnoseErrors) {
1451   assert(
1452       A->getOption().matches(options::OPT_fexperimental_sanitize_metadata_EQ) ||
1453       A->getOption().matches(
1454           options::OPT_fno_experimental_sanitize_metadata_EQ));
1455   int Features = 0;
1456   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
1457     const char *Value = A->getValue(i);
1458     int F = llvm::StringSwitch<int>(Value)
1459                 .Case("covered", BinaryMetadataCovered)
1460                 .Case("atomics", BinaryMetadataAtomics)
1461                 .Case("uar", BinaryMetadataUAR)
1462                 .Case("all", ~0)
1463                 .Default(0);
1464     if (F == 0 && DiagnoseErrors)
1465       D.Diag(clang::diag::err_drv_unsupported_option_argument)
1466           << A->getSpelling() << Value;
1467     Features |= F;
1468   }
1469   return Features;
1470 }
1471 
1472 std::string lastArgumentForMask(const Driver &D, const llvm::opt::ArgList &Args,
1473                                 SanitizerMask Mask) {
1474   for (llvm::opt::ArgList::const_reverse_iterator I = Args.rbegin(),
1475                                                   E = Args.rend();
1476        I != E; ++I) {
1477     const auto *Arg = *I;
1478     if (Arg->getOption().matches(options::OPT_fsanitize_EQ)) {
1479       SanitizerMask AddKinds =
1480           expandSanitizerGroups(parseArgValues(D, Arg, false));
1481       if (AddKinds & Mask)
1482         return describeSanitizeArg(Arg, Mask);
1483     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_EQ)) {
1484       SanitizerMask RemoveKinds =
1485           expandSanitizerGroups(parseArgValues(D, Arg, false));
1486       Mask &= ~RemoveKinds;
1487     }
1488   }
1489   llvm_unreachable("arg list didn't provide expected value");
1490 }
1491 
1492 std::string describeSanitizeArg(const llvm::opt::Arg *A, SanitizerMask Mask) {
1493   assert(A->getOption().matches(options::OPT_fsanitize_EQ) &&
1494          "Invalid argument in describeSanitizerArg!");
1495 
1496   std::string Sanitizers;
1497   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
1498     if (expandSanitizerGroups(
1499             parseSanitizerValue(A->getValue(i), /*AllowGroups=*/true)) &
1500         Mask) {
1501       if (!Sanitizers.empty())
1502         Sanitizers += ",";
1503       Sanitizers += A->getValue(i);
1504     }
1505   }
1506 
1507   assert(!Sanitizers.empty() && "arg didn't provide expected value");
1508   return "-fsanitize=" + Sanitizers;
1509 }
1510