xref: /freebsd/contrib/llvm-project/clang/lib/Driver/SanitizerArgs.cpp (revision 0bf56da32d83fbd3b5db8d6c72cd1e7cc26fbc66)
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 (D.getVFS().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, SystemBlacklistFiles);
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 (D.getVFS().exists(BLPath)) {
567         UserBlacklistFiles.push_back(BLPath);
568       } else {
569         D.Diag(clang::diag::err_drv_no_such_file) << BLPath;
570       }
571     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_blacklist)) {
572       Arg->claim();
573       UserBlacklistFiles.clear();
574       SystemBlacklistFiles.clear();
575     }
576   }
577   // Validate blacklists format.
578   {
579     std::string BLError;
580     std::unique_ptr<llvm::SpecialCaseList> SCL(
581         llvm::SpecialCaseList::create(UserBlacklistFiles, D.getVFS(), BLError));
582     if (!SCL.get())
583       D.Diag(clang::diag::err_drv_malformed_sanitizer_blacklist) << BLError;
584   }
585   {
586     std::string BLError;
587     std::unique_ptr<llvm::SpecialCaseList> SCL(llvm::SpecialCaseList::create(
588         SystemBlacklistFiles, D.getVFS(), BLError));
589     if (!SCL.get())
590       D.Diag(clang::diag::err_drv_malformed_sanitizer_blacklist) << BLError;
591   }
592 
593   // Parse -f[no-]sanitize-memory-track-origins[=level] options.
594   if (AllAddedKinds & SanitizerKind::Memory) {
595     if (Arg *A =
596             Args.getLastArg(options::OPT_fsanitize_memory_track_origins_EQ,
597                             options::OPT_fsanitize_memory_track_origins,
598                             options::OPT_fno_sanitize_memory_track_origins)) {
599       if (A->getOption().matches(options::OPT_fsanitize_memory_track_origins)) {
600         MsanTrackOrigins = 2;
601       } else if (A->getOption().matches(
602                      options::OPT_fno_sanitize_memory_track_origins)) {
603         MsanTrackOrigins = 0;
604       } else {
605         StringRef S = A->getValue();
606         if (S.getAsInteger(0, MsanTrackOrigins) || MsanTrackOrigins < 0 ||
607             MsanTrackOrigins > 2) {
608           D.Diag(clang::diag::err_drv_invalid_value) << A->getAsString(Args) << S;
609         }
610       }
611     }
612     MsanUseAfterDtor =
613         Args.hasFlag(options::OPT_fsanitize_memory_use_after_dtor,
614                      options::OPT_fno_sanitize_memory_use_after_dtor,
615                      MsanUseAfterDtor);
616     NeedPIE |= !(TC.getTriple().isOSLinux() &&
617                  TC.getTriple().getArch() == llvm::Triple::x86_64);
618   } else {
619     MsanUseAfterDtor = false;
620   }
621 
622   if (AllAddedKinds & SanitizerKind::Thread) {
623     TsanMemoryAccess = Args.hasFlag(
624         options::OPT_fsanitize_thread_memory_access,
625         options::OPT_fno_sanitize_thread_memory_access, TsanMemoryAccess);
626     TsanFuncEntryExit = Args.hasFlag(
627         options::OPT_fsanitize_thread_func_entry_exit,
628         options::OPT_fno_sanitize_thread_func_entry_exit, TsanFuncEntryExit);
629     TsanAtomics =
630         Args.hasFlag(options::OPT_fsanitize_thread_atomics,
631                      options::OPT_fno_sanitize_thread_atomics, TsanAtomics);
632   }
633 
634   if (AllAddedKinds & SanitizerKind::CFI) {
635     // Without PIE, external function address may resolve to a PLT record, which
636     // can not be verified by the target module.
637     NeedPIE |= CfiCrossDso;
638     CfiICallGeneralizePointers =
639         Args.hasArg(options::OPT_fsanitize_cfi_icall_generalize_pointers);
640 
641     if (CfiCrossDso && CfiICallGeneralizePointers)
642       D.Diag(diag::err_drv_argument_not_allowed_with)
643           << "-fsanitize-cfi-cross-dso"
644           << "-fsanitize-cfi-icall-generalize-pointers";
645 
646     CfiCanonicalJumpTables =
647         Args.hasFlag(options::OPT_fsanitize_cfi_canonical_jump_tables,
648                      options::OPT_fno_sanitize_cfi_canonical_jump_tables, true);
649   }
650 
651   Stats = Args.hasFlag(options::OPT_fsanitize_stats,
652                        options::OPT_fno_sanitize_stats, false);
653 
654   if (MinimalRuntime) {
655     SanitizerMask IncompatibleMask =
656         Kinds & ~setGroupBits(CompatibleWithMinimalRuntime);
657     if (IncompatibleMask)
658       D.Diag(clang::diag::err_drv_argument_not_allowed_with)
659           << "-fsanitize-minimal-runtime"
660           << lastArgumentForMask(D, Args, IncompatibleMask);
661 
662     SanitizerMask NonTrappingCfi = Kinds & SanitizerKind::CFI & ~TrappingKinds;
663     if (NonTrappingCfi)
664       D.Diag(clang::diag::err_drv_argument_only_allowed_with)
665           << "fsanitize-minimal-runtime"
666           << "fsanitize-trap=cfi";
667   }
668 
669   // Parse -f(no-)?sanitize-coverage flags if coverage is supported by the
670   // enabled sanitizers.
671   for (const auto *Arg : Args) {
672     if (Arg->getOption().matches(options::OPT_fsanitize_coverage)) {
673       int LegacySanitizeCoverage;
674       if (Arg->getNumValues() == 1 &&
675           !StringRef(Arg->getValue(0))
676                .getAsInteger(0, LegacySanitizeCoverage)) {
677         CoverageFeatures = 0;
678         Arg->claim();
679         if (LegacySanitizeCoverage != 0) {
680           D.Diag(diag::warn_drv_deprecated_arg)
681               << Arg->getAsString(Args) << "-fsanitize-coverage=trace-pc-guard";
682         }
683         continue;
684       }
685       CoverageFeatures |= parseCoverageFeatures(D, Arg);
686 
687       // Disable coverage and not claim the flags if there is at least one
688       // non-supporting sanitizer.
689       if (!(AllAddedKinds & ~AllRemove & ~setGroupBits(SupportsCoverage))) {
690         Arg->claim();
691       } else {
692         CoverageFeatures = 0;
693       }
694     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_coverage)) {
695       Arg->claim();
696       CoverageFeatures &= ~parseCoverageFeatures(D, Arg);
697     }
698   }
699   // Choose at most one coverage type: function, bb, or edge.
700   if ((CoverageFeatures & CoverageFunc) && (CoverageFeatures & CoverageBB))
701     D.Diag(clang::diag::err_drv_argument_not_allowed_with)
702         << "-fsanitize-coverage=func"
703         << "-fsanitize-coverage=bb";
704   if ((CoverageFeatures & CoverageFunc) && (CoverageFeatures & CoverageEdge))
705     D.Diag(clang::diag::err_drv_argument_not_allowed_with)
706         << "-fsanitize-coverage=func"
707         << "-fsanitize-coverage=edge";
708   if ((CoverageFeatures & CoverageBB) && (CoverageFeatures & CoverageEdge))
709     D.Diag(clang::diag::err_drv_argument_not_allowed_with)
710         << "-fsanitize-coverage=bb"
711         << "-fsanitize-coverage=edge";
712   // Basic block tracing and 8-bit counters require some type of coverage
713   // enabled.
714   if (CoverageFeatures & CoverageTraceBB)
715     D.Diag(clang::diag::warn_drv_deprecated_arg)
716         << "-fsanitize-coverage=trace-bb"
717         << "-fsanitize-coverage=trace-pc-guard";
718   if (CoverageFeatures & Coverage8bitCounters)
719     D.Diag(clang::diag::warn_drv_deprecated_arg)
720         << "-fsanitize-coverage=8bit-counters"
721         << "-fsanitize-coverage=trace-pc-guard";
722 
723   int InsertionPointTypes = CoverageFunc | CoverageBB | CoverageEdge;
724   int InstrumentationTypes =
725       CoverageTracePC | CoverageTracePCGuard | CoverageInline8bitCounters;
726   if ((CoverageFeatures & InsertionPointTypes) &&
727       !(CoverageFeatures & InstrumentationTypes)) {
728     D.Diag(clang::diag::warn_drv_deprecated_arg)
729         << "-fsanitize-coverage=[func|bb|edge]"
730         << "-fsanitize-coverage=[func|bb|edge],[trace-pc-guard|trace-pc]";
731   }
732 
733   // trace-pc w/o func/bb/edge implies edge.
734   if (!(CoverageFeatures & InsertionPointTypes)) {
735     if (CoverageFeatures &
736         (CoverageTracePC | CoverageTracePCGuard | CoverageInline8bitCounters))
737       CoverageFeatures |= CoverageEdge;
738 
739     if (CoverageFeatures & CoverageStackDepth)
740       CoverageFeatures |= CoverageFunc;
741   }
742 
743   SharedRuntime =
744       Args.hasFlag(options::OPT_shared_libsan, options::OPT_static_libsan,
745                    TC.getTriple().isAndroid() || TC.getTriple().isOSFuchsia() ||
746                        TC.getTriple().isOSDarwin());
747 
748   ImplicitCfiRuntime = TC.getTriple().isAndroid();
749 
750   if (AllAddedKinds & SanitizerKind::Address) {
751     NeedPIE |= TC.getTriple().isOSFuchsia();
752     if (Arg *A =
753             Args.getLastArg(options::OPT_fsanitize_address_field_padding)) {
754         StringRef S = A->getValue();
755         // Legal values are 0 and 1, 2, but in future we may add more levels.
756         if (S.getAsInteger(0, AsanFieldPadding) || AsanFieldPadding < 0 ||
757             AsanFieldPadding > 2) {
758           D.Diag(clang::diag::err_drv_invalid_value) << A->getAsString(Args) << S;
759         }
760     }
761 
762     if (Arg *WindowsDebugRTArg =
763             Args.getLastArg(options::OPT__SLASH_MTd, options::OPT__SLASH_MT,
764                             options::OPT__SLASH_MDd, options::OPT__SLASH_MD,
765                             options::OPT__SLASH_LDd, options::OPT__SLASH_LD)) {
766       switch (WindowsDebugRTArg->getOption().getID()) {
767       case options::OPT__SLASH_MTd:
768       case options::OPT__SLASH_MDd:
769       case options::OPT__SLASH_LDd:
770         D.Diag(clang::diag::err_drv_argument_not_allowed_with)
771             << WindowsDebugRTArg->getAsString(Args)
772             << lastArgumentForMask(D, Args, SanitizerKind::Address);
773         D.Diag(clang::diag::note_drv_address_sanitizer_debug_runtime);
774       }
775     }
776 
777     AsanUseAfterScope = Args.hasFlag(
778         options::OPT_fsanitize_address_use_after_scope,
779         options::OPT_fno_sanitize_address_use_after_scope, AsanUseAfterScope);
780 
781     AsanPoisonCustomArrayCookie = Args.hasFlag(
782         options::OPT_fsanitize_address_poison_custom_array_cookie,
783         options::OPT_fno_sanitize_address_poison_custom_array_cookie,
784         AsanPoisonCustomArrayCookie);
785 
786     // As a workaround for a bug in gold 2.26 and earlier, dead stripping of
787     // globals in ASan is disabled by default on ELF targets.
788     // See https://sourceware.org/bugzilla/show_bug.cgi?id=19002
789     AsanGlobalsDeadStripping =
790         !TC.getTriple().isOSBinFormatELF() || TC.getTriple().isOSFuchsia() ||
791         TC.getTriple().isPS4() ||
792         Args.hasArg(options::OPT_fsanitize_address_globals_dead_stripping);
793 
794     AsanUseOdrIndicator =
795         Args.hasFlag(options::OPT_fsanitize_address_use_odr_indicator,
796                      options::OPT_fno_sanitize_address_use_odr_indicator,
797                      AsanUseOdrIndicator);
798 
799     if (AllAddedKinds & SanitizerKind::PointerCompare & ~AllRemove) {
800       AsanInvalidPointerCmp = true;
801     }
802 
803     if (AllAddedKinds & SanitizerKind::PointerSubtract & ~AllRemove) {
804       AsanInvalidPointerSub = true;
805     }
806 
807   } else {
808     AsanUseAfterScope = false;
809     // -fsanitize=pointer-compare/pointer-subtract requires -fsanitize=address.
810     SanitizerMask DetectInvalidPointerPairs =
811         SanitizerKind::PointerCompare | SanitizerKind::PointerSubtract;
812     if (AllAddedKinds & DetectInvalidPointerPairs & ~AllRemove) {
813       TC.getDriver().Diag(clang::diag::err_drv_argument_only_allowed_with)
814           << lastArgumentForMask(D, Args,
815                                  SanitizerKind::PointerCompare |
816                                      SanitizerKind::PointerSubtract)
817           << "-fsanitize=address";
818     }
819   }
820 
821   if (AllAddedKinds & SanitizerKind::HWAddress) {
822     if (Arg *HwasanAbiArg =
823             Args.getLastArg(options::OPT_fsanitize_hwaddress_abi_EQ)) {
824       HwasanAbi = HwasanAbiArg->getValue();
825       if (HwasanAbi != "platform" && HwasanAbi != "interceptor")
826         D.Diag(clang::diag::err_drv_invalid_value)
827             << HwasanAbiArg->getAsString(Args) << HwasanAbi;
828     } else {
829       HwasanAbi = "interceptor";
830     }
831   }
832 
833   if (AllAddedKinds & SanitizerKind::SafeStack) {
834     // SafeStack runtime is built into the system on Fuchsia.
835     SafeStackRuntime = !TC.getTriple().isOSFuchsia();
836   }
837 
838   LinkRuntimes =
839       Args.hasFlag(options::OPT_fsanitize_link_runtime,
840                    options::OPT_fno_sanitize_link_runtime, LinkRuntimes);
841 
842   // Parse -link-cxx-sanitizer flag.
843   LinkCXXRuntimes = Args.hasArg(options::OPT_fsanitize_link_cxx_runtime,
844                                 options::OPT_fno_sanitize_link_cxx_runtime,
845                                 LinkCXXRuntimes) ||
846                     D.CCCIsCXX();
847 
848   // Finally, initialize the set of available and recoverable sanitizers.
849   Sanitizers.Mask |= Kinds;
850   RecoverableSanitizers.Mask |= RecoverableKinds;
851   TrapSanitizers.Mask |= TrappingKinds;
852   assert(!(RecoverableKinds & TrappingKinds) &&
853          "Overlap between recoverable and trapping sanitizers");
854 }
855 
856 static std::string toString(const clang::SanitizerSet &Sanitizers) {
857   std::string Res;
858 #define SANITIZER(NAME, ID)                                                    \
859   if (Sanitizers.has(SanitizerKind::ID)) {                                     \
860     if (!Res.empty())                                                          \
861       Res += ",";                                                              \
862     Res += NAME;                                                               \
863   }
864 #include "clang/Basic/Sanitizers.def"
865   return Res;
866 }
867 
868 static void addIncludeLinkerOption(const ToolChain &TC,
869                                    const llvm::opt::ArgList &Args,
870                                    llvm::opt::ArgStringList &CmdArgs,
871                                    StringRef SymbolName) {
872   SmallString<64> LinkerOptionFlag;
873   LinkerOptionFlag = "--linker-option=/include:";
874   if (TC.getTriple().getArch() == llvm::Triple::x86) {
875     // Win32 mangles C function names with a '_' prefix.
876     LinkerOptionFlag += '_';
877   }
878   LinkerOptionFlag += SymbolName;
879   CmdArgs.push_back(Args.MakeArgString(LinkerOptionFlag));
880 }
881 
882 static bool hasTargetFeatureMTE(const llvm::opt::ArgStringList &CmdArgs) {
883   for (auto Start = CmdArgs.begin(), End = CmdArgs.end(); Start != End; ++Start) {
884     auto It = std::find(Start, End, StringRef("+mte"));
885     if (It == End)
886       break;
887     if (It > Start && *std::prev(It) == StringRef("-target-feature"))
888       return true;
889     Start = It;
890   }
891   return false;
892 }
893 
894 void SanitizerArgs::addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
895                             llvm::opt::ArgStringList &CmdArgs,
896                             types::ID InputType) const {
897   // NVPTX doesn't currently support sanitizers.  Bailing out here means that
898   // e.g. -fsanitize=address applies only to host code, which is what we want
899   // for now.
900   if (TC.getTriple().isNVPTX())
901     return;
902 
903   // Translate available CoverageFeatures to corresponding clang-cc1 flags.
904   // Do it even if Sanitizers.empty() since some forms of coverage don't require
905   // sanitizers.
906   std::pair<int, const char *> CoverageFlags[] = {
907     std::make_pair(CoverageFunc, "-fsanitize-coverage-type=1"),
908     std::make_pair(CoverageBB, "-fsanitize-coverage-type=2"),
909     std::make_pair(CoverageEdge, "-fsanitize-coverage-type=3"),
910     std::make_pair(CoverageIndirCall, "-fsanitize-coverage-indirect-calls"),
911     std::make_pair(CoverageTraceBB, "-fsanitize-coverage-trace-bb"),
912     std::make_pair(CoverageTraceCmp, "-fsanitize-coverage-trace-cmp"),
913     std::make_pair(CoverageTraceDiv, "-fsanitize-coverage-trace-div"),
914     std::make_pair(CoverageTraceGep, "-fsanitize-coverage-trace-gep"),
915     std::make_pair(Coverage8bitCounters, "-fsanitize-coverage-8bit-counters"),
916     std::make_pair(CoverageTracePC, "-fsanitize-coverage-trace-pc"),
917     std::make_pair(CoverageTracePCGuard, "-fsanitize-coverage-trace-pc-guard"),
918     std::make_pair(CoverageInline8bitCounters, "-fsanitize-coverage-inline-8bit-counters"),
919     std::make_pair(CoveragePCTable, "-fsanitize-coverage-pc-table"),
920     std::make_pair(CoverageNoPrune, "-fsanitize-coverage-no-prune"),
921     std::make_pair(CoverageStackDepth, "-fsanitize-coverage-stack-depth")};
922   for (auto F : CoverageFlags) {
923     if (CoverageFeatures & F.first)
924       CmdArgs.push_back(F.second);
925   }
926 
927   if (TC.getTriple().isOSWindows() && needsUbsanRt()) {
928     // Instruct the code generator to embed linker directives in the object file
929     // that cause the required runtime libraries to be linked.
930     CmdArgs.push_back(Args.MakeArgString(
931         "--dependent-lib=" + TC.getCompilerRT(Args, "ubsan_standalone")));
932     if (types::isCXX(InputType))
933       CmdArgs.push_back(Args.MakeArgString(
934           "--dependent-lib=" + TC.getCompilerRT(Args, "ubsan_standalone_cxx")));
935   }
936   if (TC.getTriple().isOSWindows() && needsStatsRt()) {
937     CmdArgs.push_back(Args.MakeArgString("--dependent-lib=" +
938                                          TC.getCompilerRT(Args, "stats_client")));
939 
940     // The main executable must export the stats runtime.
941     // FIXME: Only exporting from the main executable (e.g. based on whether the
942     // translation unit defines main()) would save a little space, but having
943     // multiple copies of the runtime shouldn't hurt.
944     CmdArgs.push_back(Args.MakeArgString("--dependent-lib=" +
945                                          TC.getCompilerRT(Args, "stats")));
946     addIncludeLinkerOption(TC, Args, CmdArgs, "__sanitizer_stats_register");
947   }
948 
949   if (Sanitizers.empty())
950     return;
951   CmdArgs.push_back(Args.MakeArgString("-fsanitize=" + toString(Sanitizers)));
952 
953   if (!RecoverableSanitizers.empty())
954     CmdArgs.push_back(Args.MakeArgString("-fsanitize-recover=" +
955                                          toString(RecoverableSanitizers)));
956 
957   if (!TrapSanitizers.empty())
958     CmdArgs.push_back(
959         Args.MakeArgString("-fsanitize-trap=" + toString(TrapSanitizers)));
960 
961   for (const auto &BLPath : UserBlacklistFiles) {
962     SmallString<64> BlacklistOpt("-fsanitize-blacklist=");
963     BlacklistOpt += BLPath;
964     CmdArgs.push_back(Args.MakeArgString(BlacklistOpt));
965   }
966   for (const auto &BLPath : SystemBlacklistFiles) {
967     SmallString<64> BlacklistOpt("-fsanitize-system-blacklist=");
968     BlacklistOpt += BLPath;
969     CmdArgs.push_back(Args.MakeArgString(BlacklistOpt));
970   }
971 
972   if (MsanTrackOrigins)
973     CmdArgs.push_back(Args.MakeArgString("-fsanitize-memory-track-origins=" +
974                                          Twine(MsanTrackOrigins)));
975 
976   if (MsanUseAfterDtor)
977     CmdArgs.push_back("-fsanitize-memory-use-after-dtor");
978 
979   // FIXME: Pass these parameters as function attributes, not as -llvm flags.
980   if (!TsanMemoryAccess) {
981     CmdArgs.push_back("-mllvm");
982     CmdArgs.push_back("-tsan-instrument-memory-accesses=0");
983     CmdArgs.push_back("-mllvm");
984     CmdArgs.push_back("-tsan-instrument-memintrinsics=0");
985   }
986   if (!TsanFuncEntryExit) {
987     CmdArgs.push_back("-mllvm");
988     CmdArgs.push_back("-tsan-instrument-func-entry-exit=0");
989   }
990   if (!TsanAtomics) {
991     CmdArgs.push_back("-mllvm");
992     CmdArgs.push_back("-tsan-instrument-atomics=0");
993   }
994 
995   if (CfiCrossDso)
996     CmdArgs.push_back("-fsanitize-cfi-cross-dso");
997 
998   if (CfiICallGeneralizePointers)
999     CmdArgs.push_back("-fsanitize-cfi-icall-generalize-pointers");
1000 
1001   if (CfiCanonicalJumpTables)
1002     CmdArgs.push_back("-fsanitize-cfi-canonical-jump-tables");
1003 
1004   if (Stats)
1005     CmdArgs.push_back("-fsanitize-stats");
1006 
1007   if (MinimalRuntime)
1008     CmdArgs.push_back("-fsanitize-minimal-runtime");
1009 
1010   if (AsanFieldPadding)
1011     CmdArgs.push_back(Args.MakeArgString("-fsanitize-address-field-padding=" +
1012                                          Twine(AsanFieldPadding)));
1013 
1014   if (AsanUseAfterScope)
1015     CmdArgs.push_back("-fsanitize-address-use-after-scope");
1016 
1017   if (AsanPoisonCustomArrayCookie)
1018     CmdArgs.push_back("-fsanitize-address-poison-custom-array-cookie");
1019 
1020   if (AsanGlobalsDeadStripping)
1021     CmdArgs.push_back("-fsanitize-address-globals-dead-stripping");
1022 
1023   if (AsanUseOdrIndicator)
1024     CmdArgs.push_back("-fsanitize-address-use-odr-indicator");
1025 
1026   if (AsanInvalidPointerCmp) {
1027     CmdArgs.push_back("-mllvm");
1028     CmdArgs.push_back("-asan-detect-invalid-pointer-cmp");
1029   }
1030 
1031   if (AsanInvalidPointerSub) {
1032     CmdArgs.push_back("-mllvm");
1033     CmdArgs.push_back("-asan-detect-invalid-pointer-sub");
1034   }
1035 
1036   if (!HwasanAbi.empty()) {
1037     CmdArgs.push_back("-default-function-attr");
1038     CmdArgs.push_back(Args.MakeArgString("hwasan-abi=" + HwasanAbi));
1039   }
1040 
1041   if (Sanitizers.has(SanitizerKind::HWAddress)) {
1042     CmdArgs.push_back("-target-feature");
1043     CmdArgs.push_back("+tagged-globals");
1044   }
1045 
1046   // MSan: Workaround for PR16386.
1047   // ASan: This is mainly to help LSan with cases such as
1048   // https://github.com/google/sanitizers/issues/373
1049   // We can't make this conditional on -fsanitize=leak, as that flag shouldn't
1050   // affect compilation.
1051   if (Sanitizers.has(SanitizerKind::Memory) ||
1052       Sanitizers.has(SanitizerKind::Address))
1053     CmdArgs.push_back("-fno-assume-sane-operator-new");
1054 
1055   // Require -fvisibility= flag on non-Windows when compiling if vptr CFI is
1056   // enabled.
1057   if (Sanitizers.hasOneOf(CFIClasses) && !TC.getTriple().isOSWindows() &&
1058       !Args.hasArg(options::OPT_fvisibility_EQ)) {
1059     TC.getDriver().Diag(clang::diag::err_drv_argument_only_allowed_with)
1060         << lastArgumentForMask(TC.getDriver(), Args,
1061                                Sanitizers.Mask & CFIClasses)
1062         << "-fvisibility=";
1063   }
1064 
1065   if (Sanitizers.has(SanitizerKind::MemTag) && !hasTargetFeatureMTE(CmdArgs))
1066     TC.getDriver().Diag(diag::err_stack_tagging_requires_hardware_feature);
1067 }
1068 
1069 SanitizerMask parseArgValues(const Driver &D, const llvm::opt::Arg *A,
1070                              bool DiagnoseErrors) {
1071   assert((A->getOption().matches(options::OPT_fsanitize_EQ) ||
1072           A->getOption().matches(options::OPT_fno_sanitize_EQ) ||
1073           A->getOption().matches(options::OPT_fsanitize_recover_EQ) ||
1074           A->getOption().matches(options::OPT_fno_sanitize_recover_EQ) ||
1075           A->getOption().matches(options::OPT_fsanitize_trap_EQ) ||
1076           A->getOption().matches(options::OPT_fno_sanitize_trap_EQ)) &&
1077          "Invalid argument in parseArgValues!");
1078   SanitizerMask Kinds;
1079   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
1080     const char *Value = A->getValue(i);
1081     SanitizerMask Kind;
1082     // Special case: don't accept -fsanitize=all.
1083     if (A->getOption().matches(options::OPT_fsanitize_EQ) &&
1084         0 == strcmp("all", Value))
1085       Kind = SanitizerMask();
1086     else
1087       Kind = parseSanitizerValue(Value, /*AllowGroups=*/true);
1088 
1089     if (Kind)
1090       Kinds |= Kind;
1091     else if (DiagnoseErrors)
1092       D.Diag(clang::diag::err_drv_unsupported_option_argument)
1093           << A->getOption().getName() << Value;
1094   }
1095   return Kinds;
1096 }
1097 
1098 int parseCoverageFeatures(const Driver &D, const llvm::opt::Arg *A) {
1099   assert(A->getOption().matches(options::OPT_fsanitize_coverage) ||
1100          A->getOption().matches(options::OPT_fno_sanitize_coverage));
1101   int Features = 0;
1102   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
1103     const char *Value = A->getValue(i);
1104     int F = llvm::StringSwitch<int>(Value)
1105         .Case("func", CoverageFunc)
1106         .Case("bb", CoverageBB)
1107         .Case("edge", CoverageEdge)
1108         .Case("indirect-calls", CoverageIndirCall)
1109         .Case("trace-bb", CoverageTraceBB)
1110         .Case("trace-cmp", CoverageTraceCmp)
1111         .Case("trace-div", CoverageTraceDiv)
1112         .Case("trace-gep", CoverageTraceGep)
1113         .Case("8bit-counters", Coverage8bitCounters)
1114         .Case("trace-pc", CoverageTracePC)
1115         .Case("trace-pc-guard", CoverageTracePCGuard)
1116         .Case("no-prune", CoverageNoPrune)
1117         .Case("inline-8bit-counters", CoverageInline8bitCounters)
1118         .Case("pc-table", CoveragePCTable)
1119         .Case("stack-depth", CoverageStackDepth)
1120         .Default(0);
1121     if (F == 0)
1122       D.Diag(clang::diag::err_drv_unsupported_option_argument)
1123           << A->getOption().getName() << Value;
1124     Features |= F;
1125   }
1126   return Features;
1127 }
1128 
1129 std::string lastArgumentForMask(const Driver &D, const llvm::opt::ArgList &Args,
1130                                 SanitizerMask Mask) {
1131   for (llvm::opt::ArgList::const_reverse_iterator I = Args.rbegin(),
1132                                                   E = Args.rend();
1133        I != E; ++I) {
1134     const auto *Arg = *I;
1135     if (Arg->getOption().matches(options::OPT_fsanitize_EQ)) {
1136       SanitizerMask AddKinds =
1137           expandSanitizerGroups(parseArgValues(D, Arg, false));
1138       if (AddKinds & Mask)
1139         return describeSanitizeArg(Arg, Mask);
1140     } else if (Arg->getOption().matches(options::OPT_fno_sanitize_EQ)) {
1141       SanitizerMask RemoveKinds =
1142           expandSanitizerGroups(parseArgValues(D, Arg, false));
1143       Mask &= ~RemoveKinds;
1144     }
1145   }
1146   llvm_unreachable("arg list didn't provide expected value");
1147 }
1148 
1149 std::string describeSanitizeArg(const llvm::opt::Arg *A, SanitizerMask Mask) {
1150   assert(A->getOption().matches(options::OPT_fsanitize_EQ)
1151          && "Invalid argument in describeSanitizerArg!");
1152 
1153   std::string Sanitizers;
1154   for (int i = 0, n = A->getNumValues(); i != n; ++i) {
1155     if (expandSanitizerGroups(
1156             parseSanitizerValue(A->getValue(i), /*AllowGroups=*/true)) &
1157         Mask) {
1158       if (!Sanitizers.empty())
1159         Sanitizers += ",";
1160       Sanitizers += A->getValue(i);
1161     }
1162   }
1163 
1164   assert(!Sanitizers.empty() && "arg didn't provide expected value");
1165   return "-fsanitize=" + Sanitizers;
1166 }
1167