[clang][cli] Generate and round-trip language options

[jansvoboda11]

Summary

This patch implements generation of remaining language options and tests it by performing parse-generate-parse round trip (on by default for assert builds, off otherwise).

This patch also correctly reports failures in parseSanitizerKinds, which is necessary for emitting diagnostics when an invalid sanitizer is passed to -fsanitize= during round-trip.

This patch also removes TableGen marshalling classes from two options:

• fsanitize_blacklist When parsing: it's first initialized via the generated code, but then also changed by manually written code, which is confusing.
• fopenmp When parsing: it's first initialized via generated code, but then conditionally changed by manually written code. This is also confusing. Moreover, we need to do some extra checks when generating it, which would be really cumbersome in TableGen. (Specifically, not emitting it when -fopenmp-simd was present.)

[dexonsmith]

clang/lib/Frontend/CompilerInvocation.cpp

1201

Can the caller use Diags.hasErrorOccurred() to avoid this change?

[jansvoboda11]

clang/lib/Frontend/CompilerInvocation.cpp

1201

Not really, because the caller might have Diags that already contains some errors. We could compare the number of errors in Diags before and after calling this function. DiagnosticsEngine doesn't have API for that, but that could be added without much issues.

Do you have any specific reason for avoiding this change beyond minimizing the diff?

[dexonsmith]

LGTM, since I don't think the parallel error paths are too bad in this specific patch, but see my longer comment inline.

clang/lib/Frontend/CompilerInvocation.cpp

1201

Not really, because the caller might have Diags that already contains some errors. We could compare the number of errors in Diags before and after calling this function. DiagnosticsEngine doesn't have API for that, but that could be added without much issues.

Why not just return "failure" at the top level if any error has occurred? Why do we need to know if a specific parse routine failed?

If we have top-level callers that send in a DiagnosticEngine that has already been called, maybe we can change them to call Reset before entering.

Do you have any specific reason for avoiding this change beyond minimizing the diff?

It's just fragile; it's a manual step to update Success every time an error is reported. Having two paths to give the same information is awkward and error-prone.

It'd be nice to have a hook that did both, so you could do something like:

reportError(diag::err_drv_invalid_value) << FlagName << Sanitizer;

and reportError would be something like:

auto reportError = [&Diags,&Success](OptSpecifier Opt) {
  Success = false;
  return Diags.Report(Opt);
};

or to ensure warnings in the same interface, maybe could have:

auto reportDiag = [&Diags,&Success](OptSpecifier Opt) {
  Success &= Diags.getDiagnosticLevel() >= DiagnosticsEngine::Error;
  return Diags.Report(Opt);
};

Not necessarily worth it for this patch (you can commit as-is), but if we're going to have to update swaths of code in this way it would be good to encapsulate the pattern somehow.

[jansvoboda11]

Fix failures of tests that invoke -cc1 directly

[jansvoboda11]

Revert reporting failure when parsing sanitizers

[jansvoboda11]

Add comment, remove unnecessary diff

clang/include/clang/Basic/Sanitizers.h

 //===- Sanitizers.h - C Language Family Language Options --------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
struct SanitizerSet {
   /// Bitmask of enabled sanitizers.
   SanitizerMask Mask;
 };
 
 /// Parse a single value from a -fsanitize= or -fno-sanitize= value list.
 /// Returns a non-zero SanitizerMask, or \c 0 if \p Value is not known.
 SanitizerMask parseSanitizerValue(StringRef Value, bool AllowGroups);
 
+/// Serialize a SanitizerSet into values for -fsanitize= or -fno-sanitize=.
+void serializeSanitizerSet(SanitizerSet Set,
+                           SmallVectorImpl<StringRef> &Values);
+
 /// For each sanitizer group bit set in \p Kinds, set the bits for sanitizers
 /// this group enables.
 SanitizerMask expandSanitizerGroups(SanitizerMask Kinds);
 
 /// Return the sanitizers which do not affect preprocessing.
 inline SanitizerMask getPPTransparentSanitizers() {
   return SanitizerKind::CFI | SanitizerKind::Integer |
          SanitizerKind::ImplicitConversion | SanitizerKind::Nullability |
          SanitizerKind::Undefined | SanitizerKind::FloatDivideByZero;
 }
 
 } // namespace clang
 
 #endif // LLVM_CLANG_BASIC_SANITIZERS_H

clang/include/clang/Driver/Options.td

 def fsanitize_EQ : CommaJoined<["-"], "fsanitize=">, Group<f_clang_Group>,
                    MetaVarName<"<check>">,
                    HelpText<"Turn on runtime checks for various forms of undefined "
                             "or suspicious behavior. See user manual for available checks">;
 def fno_sanitize_EQ : CommaJoined<["-"], "fno-sanitize=">, Group<f_clang_Group>,
                       Flags<[CoreOption, NoXarchOption]>;
 def fsanitize_blacklist : Joined<["-"], "fsanitize-blacklist=">,
                           Group<f_clang_Group>,
-                          HelpText<"Path to blacklist file for sanitizers">,
-                          MarshallingInfoStringVector<LangOpts<"SanitizerBlacklistFiles">>;
+                          HelpText<"Path to blacklist file for sanitizers">;
 def fsanitize_system_blacklist : Joined<["-"], "fsanitize-system-blacklist=">,
   HelpText<"Path to system blacklist file for sanitizers">,
   Flags<[CC1Option]>;
 def fno_sanitize_blacklist : Flag<["-"], "fno-sanitize-blacklist">,
                              Group<f_clang_Group>,
                              HelpText<"Don't use blacklist file for sanitizers">;
 def fsanitize_coverage
     : CommaJoined<["-"], "fsanitize-coverage=">,

 def fobjc_abi_version_EQ : Joined<["-"], "fobjc-abi-version=">, Group<f_Group>;
 def fobjc_nonfragile_abi_version_EQ : Joined<["-"], "fobjc-nonfragile-abi-version=">, Group<f_Group>;
 def fobjc_nonfragile_abi : Flag<["-"], "fobjc-nonfragile-abi">, Group<f_Group>;
 def fno_objc_nonfragile_abi : Flag<["-"], "fno-objc-nonfragile-abi">, Group<f_Group>;
 
 def fobjc_sender_dependent_dispatch : Flag<["-"], "fobjc-sender-dependent-dispatch">, Group<f_Group>;
 def fomit_frame_pointer : Flag<["-"], "fomit-frame-pointer">, Group<f_Group>;
 def fopenmp : Flag<["-"], "fopenmp">, Group<f_Group>, Flags<[CC1Option, NoArgumentUnused]>,
-  HelpText<"Parse OpenMP pragmas and generate parallel code.">,
-  MarshallingInfoFlag<LangOpts<"OpenMP">, "0u">, Normalizer<"makeFlagToValueNormalizer(50u)">;
+  HelpText<"Parse OpenMP pragmas and generate parallel code.">;
 def fno_openmp : Flag<["-"], "fno-openmp">, Group<f_Group>, Flags<[NoArgumentUnused]>;
 def fopenmp_version_EQ : Joined<["-"], "fopenmp-version=">, Group<f_Group>, Flags<[CC1Option, NoArgumentUnused]>;
 def fopenmp_EQ : Joined<["-"], "fopenmp=">, Group<f_Group>;
 def fopenmp_use_tls : Flag<["-"], "fopenmp-use-tls">, Group<f_Group>,
   Flags<[NoArgumentUnused, HelpHidden]>;
 def fnoopenmp_use_tls : Flag<["-"], "fnoopenmp-use-tls">, Group<f_Group>,
   Flags<[CC1Option, NoArgumentUnused, HelpHidden]>;
 def fopenmp_targets_EQ : CommaJoined<["-"], "fopenmp-targets=">, Flags<[NoXarchOption, CC1Option]>,

clang/include/clang/Frontend/CompilerInvocation.h

 //===- CompilerInvocation.h - Compiler Invocation Helper Data ---*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
private:
   ///
   /// \param Args - The argument list containing the arguments to parse
   /// \param Diags - The DiagnosticsEngine associated with CreateFromArgs
   /// \returns - True if parsing was successful, false otherwise
   bool parseSimpleArgs(const llvm::opt::ArgList &Args,
                        DiagnosticsEngine &Diags);
 
   /// Parse command line options that map to LangOptions.
-  static bool ParseLangArgs(LangOptions &Opts, llvm::opt::ArgList &Args,
+  static bool ParseLangArgsImpl(LangOptions &Opts, llvm::opt::ArgList &Args,
                                 InputKind IK, const llvm::Triple &T,
                                 std::vector<std::string> &Includes,
                                 DiagnosticsEngine &Diags);
 
+  static bool ParseLangArgs(CompilerInvocation &Res, LangOptions &Opts,
+                            llvm::opt::ArgList &Args, InputKind IK,
+                            const llvm::Triple &T,
+                            std::vector<std::string> &Includes,
+                            DiagnosticsEngine &Diags);
+
+  /// Generate command line options from LangOptions.
+  static void GenerateLangArgs(const LangOptions &Opts,
+                               SmallVectorImpl<const char *> &Args,
+                               StringAllocator SA, const llvm::Triple &T);
+
   /// Parse command line options that map to CodeGenOptions.
   static bool ParseCodeGenArgs(CodeGenOptions &Opts, llvm::opt::ArgList &Args,
                                InputKind IK, DiagnosticsEngine &Diags,
                                const llvm::Triple &T,
                                const std::string &OutputFile,
                                const LangOptions &LangOptsRef);
 
   /// Parse command line options that map to HeaderSearchOptions.

clang/lib/Basic/Sanitizers.cpp

 //===- Sanitizers.cpp - C Language Family Language Options ----------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 //  This file defines the classes from Sanitizers.h
 //
 //===----------------------------------------------------------------------===//
 
 #include "clang/Basic/Sanitizers.h"
 #include "llvm/ADT/Hashing.h"
+#include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringSwitch.h"
 
 using namespace clang;
 
 // Once LLVM switches to C++17, the constexpr variables can be inline and we
 // won't need this.
 #define SANITIZER(NAME, ID) constexpr SanitizerMask SanitizerKind::ID;
 #define SANITIZER_GROUP(NAME, ID, ALIAS)                                       \
   constexpr SanitizerMask SanitizerKind::ID;                                   \
   constexpr SanitizerMask SanitizerKind::ID##Group;
 #include "clang/Basic/Sanitizers.def"
 
 SanitizerMask clang::parseSanitizerValue(StringRef Value, bool AllowGroups) {
   SanitizerMask ParsedKind = llvm::StringSwitch<SanitizerMask>(Value)
 #define SANITIZER(NAME, ID) .Case(NAME, SanitizerKind::ID)
 #define SANITIZER_GROUP(NAME, ID, ALIAS)                                       \
   .Case(NAME, AllowGroups ? SanitizerKind::ID##Group : SanitizerMask())
 #include "clang/Basic/Sanitizers.def"
     .Default(SanitizerMask());
   return ParsedKind;
 }
 
+void clang::serializeSanitizerSet(SanitizerSet Set,
+                                  SmallVectorImpl<StringRef> &Values) {
+#define SANITIZER(NAME, ID)                                                    \
+  if (Set.has(SanitizerKind::ID))                                              \
+    Values.push_back(NAME);
+#include "clang/Basic/Sanitizers.def"
+}
+
 SanitizerMask clang::expandSanitizerGroups(SanitizerMask Kinds) {
 #define SANITIZER(NAME, ID)
 #define SANITIZER_GROUP(NAME, ID, ALIAS)                                       \
   if (Kinds & SanitizerKind::ID##Group)                                        \
     Kinds |= SanitizerKind::ID;
 #include "clang/Basic/Sanitizers.def"
   return Kinds;
 }

clang/lib/Frontend/CompilerInvocation.cpp

 //===- CompilerInvocation.cpp ---------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
static void denormalizeStringImpl(SmallVectorImpl<const char *> &Args,
                                   const Twine &Value) {
   switch (OptClass) {
   case Option::SeparateClass:
   case Option::JoinedOrSeparateClass:
     Args.push_back(Spelling);
     Args.push_back(SA(Value));
     break;
   case Option::JoinedClass:
+  case Option::CommaJoinedClass:
     Args.push_back(SA(Twine(Spelling) + Value));
     break;
   default:
     llvm_unreachable("Cannot denormalize an option with option class "
                      "incompatible with string denormalization.");
   }
 }
 
for (const auto &Level : Levels) {
     }
     M = M | PM;
   }
   return Success;
 }
 
 static void parseSanitizerKinds(StringRef FlagName,
                                 const std::vector<std::string> &Sanitizers,
                                 DiagnosticsEngine &Diags, SanitizerSet &S) {
   for (const auto &Sanitizer : Sanitizers) {
     SanitizerMask K = parseSanitizerValue(Sanitizer, /*AllowGroups=*/false);
     if (K == SanitizerMask())
       Diags.Report(diag::err_drv_invalid_value) << FlagName << Sanitizer;
     else
       S.set(K, true);
   }
 }
 
+static SmallVector<StringRef, 4> serializeSanitizerKinds(SanitizerSet S) {
+  SmallVector<StringRef, 4> Values;
+  serializeSanitizerSet(S, Values);
+  return Values;
+}
+
 static void parseXRayInstrumentationBundle(StringRef FlagName, StringRef Bundle,
                                            ArgList &Args, DiagnosticsEngine &D,
                                            XRayInstrSet &S) {
   llvm::SmallVector<StringRef, 2> BundleParts;
   llvm::SplitString(Bundle, BundleParts, ",");
   for (const auto &B : BundleParts) {
     auto Mask = parseXRayInstrValue(B);
     if (Mask == XRayInstrKind::None)
case Language::LLVM_IR:
     return "LLVM IR";
 
   case Language::Unknown:
     break;
   }
   llvm_unreachable("unknown input language");
 }
 
-static void GenerateLangArgs(const LangOptions &Opts,
+void CompilerInvocation::GenerateLangArgs(const LangOptions &Opts,
                                           SmallVectorImpl<const char *> &Args,
-                             CompilerInvocation::StringAllocator SA) {
+                                          StringAllocator SA,
+                                          const llvm::Triple &T) {
+  OptSpecifier StdOpt;
+  switch (Opts.LangStd) {
+  case LangStandard::lang_opencl10:
+  case LangStandard::lang_opencl11:
+  case LangStandard::lang_opencl12:
+  case LangStandard::lang_opencl20:
+  case LangStandard::lang_opencl30:
+  case LangStandard::lang_openclcpp:
+    StdOpt = OPT_cl_std_EQ;
+    break;
+  default:
+    StdOpt = OPT_std_EQ;
+    break;
+  }
+
+  auto LangStandard = LangStandard::getLangStandardForKind(Opts.LangStd);
+  GenerateArg(Args, StdOpt, LangStandard.getName(), SA);
+
   if (Opts.IncludeDefaultHeader)
     GenerateArg(Args, OPT_finclude_default_header, SA);
   if (Opts.DeclareOpenCLBuiltins)
     GenerateArg(Args, OPT_fdeclare_opencl_builtins, SA);
+
+  const LangOptions *LangOpts = &Opts;
+
+#define LANG_OPTION_WITH_MARSHALLING(                                          \
+    PREFIX_TYPE, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,        \
+    HELPTEXT, METAVAR, VALUES, SPELLING, SHOULD_PARSE, ALWAYS_EMIT, KEYPATH,   \
+    DEFAULT_VALUE, IMPLIED_CHECK, IMPLIED_VALUE, NORMALIZER, DENORMALIZER,     \
+    MERGER, EXTRACTOR, TABLE_INDEX)                                            \
+  GENERATE_OPTION_WITH_MARSHALLING(                                            \
+      Args, SA, KIND, FLAGS, SPELLING, ALWAYS_EMIT, KEYPATH, DEFAULT_VALUE,    \
+      IMPLIED_CHECK, IMPLIED_VALUE, DENORMALIZER, EXTRACTOR, TABLE_INDEX)
+#include "clang/Driver/Options.inc"
+#undef LANG_OPTION_WITH_MARSHALLING
+
+  // The '-fcf-protection=' option is generated by CodeGenOpts generator.
+
+  if (Opts.ObjC) {
+    std::string Buffer;
+    llvm::raw_string_ostream Stream(Buffer);
+    Stream << Opts.ObjCRuntime;
+    GenerateArg(Args, OPT_fobjc_runtime_EQ, Stream.str(), SA);
+
+    if (Opts.GC == LangOptions::GCOnly)
+      GenerateArg(Args, OPT_fobjc_gc_only, SA);
+    else if (Opts.GC == LangOptions::HybridGC)
+      GenerateArg(Args, OPT_fobjc_gc, SA);
+    else if (Opts.ObjCAutoRefCount == 1)
+      GenerateArg(Args, OPT_fobjc_arc, SA);
+
+    if (Opts.ObjCWeakRuntime)
+      GenerateArg(Args, OPT_fobjc_runtime_has_weak, SA);
+
+    if (Opts.ObjCWeak)
+      GenerateArg(Args, OPT_fobjc_weak, SA);
+
+    if (Opts.ObjCSubscriptingLegacyRuntime)
+      GenerateArg(Args, OPT_fobjc_subscripting_legacy_runtime, SA);
+  }
+
+  if (Opts.GNUCVersion != 0) {
+    unsigned Major = Opts.GNUCVersion / 100 / 100;
+    unsigned Minor = (Opts.GNUCVersion / 100) % 100;
+    unsigned Patch = Opts.GNUCVersion % 100;
+    GenerateArg(Args, OPT_fgnuc_version_EQ,
+                Twine(Major) + "." + Twine(Minor) + "." + Twine(Patch), SA);
+  }
+
+  if (Opts.SignedOverflowBehavior == LangOptions::SOB_Trapping) {
+    GenerateArg(Args, OPT_ftrapv, SA);
+    GenerateArg(Args, OPT_ftrapv_handler, Opts.OverflowHandler, SA);
+  } else if (Opts.SignedOverflowBehavior == LangOptions::SOB_Defined) {
+    GenerateArg(Args, OPT_fwrapv, SA);
+  }
+
+  if (Opts.MSCompatibilityVersion != 0) {
+    unsigned Major = Opts.MSCompatibilityVersion / 10000000;
+    unsigned Minor = (Opts.MSCompatibilityVersion / 100000) % 100;
+    unsigned Subminor = Opts.MSCompatibilityVersion % 100000;
+    GenerateArg(Args, OPT_fms_compatibility_version,
+                Twine(Major) + "." + Twine(Minor) + "." + Twine(Subminor), SA);
+  }
+
+  if ((!Opts.GNUMode && !Opts.MSVCCompat && !Opts.CPlusPlus17) || T.isOSzOS()) {
+    if (!Opts.Trigraphs)
+      GenerateArg(Args, OPT_fno_trigraphs, SA);
+  } else {
+    if (Opts.Trigraphs)
+      GenerateArg(Args, OPT_ftrigraphs, SA);
+  }
+
+  if (Opts.Blocks && !(Opts.OpenCL && Opts.OpenCLVersion == 200))
+    GenerateArg(Args, OPT_fblocks, SA);
+
+  if (Opts.ConvergentFunctions &&
+      !(Opts.OpenCL || (Opts.CUDA && Opts.CUDAIsDevice) || Opts.SYCLIsDevice))
+    GenerateArg(Args, OPT_fconvergent_functions, SA);
+
+  if (Opts.NoBuiltin && !Opts.Freestanding)
+    GenerateArg(Args, OPT_fno_builtin, SA);
+
+  // Not generating '-fno-builtin-xxx'. It's handled for CodeGenOptions, that
+  // also read OPT_fno_builtin_.
+
+  if (Opts.LongDoubleSize == 128)
+    GenerateArg(Args, OPT_mlong_double_128, SA);
+  else if (Opts.LongDoubleSize == 64)
+    GenerateArg(Args, OPT_mlong_double_64, SA);
+
+  // Not generating '-mrtd', it's just an alias for '-fdefault-calling-conv='.
+
+  // OpenMP was requested via '-fopenmp', not implied by '-fopenmp-simd' or
+  // '-fopenmp-targets='.
+  if (Opts.OpenMP && !Opts.OpenMPSimd) {
+    GenerateArg(Args, OPT_fopenmp, SA);
+
+    if (Opts.OpenMP != 50)
+      GenerateArg(Args, OPT_fopenmp_version_EQ, Twine(Opts.OpenMP), SA);
+
+    if (!Opts.OpenMPUseTLS)
+      GenerateArg(Args, OPT_fnoopenmp_use_tls, SA);
+
+    if (Opts.OpenMPIsDevice)
+      GenerateArg(Args, OPT_fopenmp_is_device, SA);
+
+    if (Opts.OpenMPIRBuilder)
+      GenerateArg(Args, OPT_fopenmp_enable_irbuilder, SA);
+  }
+
+  if (Opts.OpenMPSimd) {
+    GenerateArg(Args, OPT_fopenmp_simd, SA);
+
+    if (Opts.OpenMP != 50)
+      GenerateArg(Args, OPT_fopenmp_version_EQ, Twine(Opts.OpenMP), SA);
   }
 
-bool CompilerInvocation::ParseLangArgs(LangOptions &Opts, ArgList &Args,
+  if (Opts.OpenMPCUDANumSMs != 0)
+    GenerateArg(Args, OPT_fopenmp_cuda_number_of_sm_EQ,
+                Twine(Opts.OpenMPCUDANumSMs), SA);
+
+  if (Opts.OpenMPCUDABlocksPerSM != 0)
+    GenerateArg(Args, OPT_fopenmp_cuda_blocks_per_sm_EQ,
+                Twine(Opts.OpenMPCUDABlocksPerSM), SA);
+
+  if (Opts.OpenMPCUDAReductionBufNum != 1024)
+    GenerateArg(Args, OPT_fopenmp_cuda_teams_reduction_recs_num_EQ,
+                Twine(Opts.OpenMPCUDAReductionBufNum), SA);
+
+  if (!Opts.OMPTargetTriples.empty()) {
+    std::string Targets;
+    llvm::raw_string_ostream OS(Targets);
+    llvm::interleave(
+        Opts.OMPTargetTriples, OS,
+        [&OS](const llvm::Triple &T) { OS << T.str(); }, ",");
+    GenerateArg(Args, OPT_fopenmp_targets_EQ, OS.str(), SA);
+  }
+
+  if (!Opts.OMPHostIRFile.empty())
+    GenerateArg(Args, OPT_fopenmp_host_ir_file_path, Opts.OMPHostIRFile, SA);
+
+  if (Opts.OpenMPCUDAMode)
+    GenerateArg(Args, OPT_fopenmp_cuda_mode, SA);
+
+  if (Opts.OpenMPCUDATargetParallel)
+    GenerateArg(Args, OPT_fopenmp_cuda_parallel_target_regions, SA);
+
+  if (Opts.OpenMPCUDAForceFullRuntime)
+    GenerateArg(Args, OPT_fopenmp_cuda_force_full_runtime, SA);
+
+  // The arguments used to set 'Optimize' and 'OptimizeSize' will be generated
+  // by CodeGenOptions.
+
+  if (Opts.NoInlineDefine && Opts.Optimize)
+    GenerateArg(Args, OPT_fno_inline, SA);
+
+  if (Opts.DefaultFPContractMode == LangOptions::FPM_Fast)
+    GenerateArg(Args, OPT_ffp_contract, "fast", SA);
+  else if (Opts.DefaultFPContractMode == LangOptions::FPM_On)
+    GenerateArg(Args, OPT_ffp_contract, "on", SA);
+  else if (Opts.DefaultFPContractMode == LangOptions::FPM_Off)
+    GenerateArg(Args, OPT_ffp_contract, "off", SA);
+  else if (Opts.DefaultFPContractMode == LangOptions::FPM_FastHonorPragmas)
+    GenerateArg(Args, OPT_ffp_contract, "fast-honor-pragmas", SA);
+
+  for (StringRef Sanitizer : serializeSanitizerKinds(Opts.Sanitize))
+    GenerateArg(Args, OPT_fsanitize_EQ, Sanitizer, SA);
+
+  // Conflating '-fsanitize-system-blacklist' and '-fsanitize-blacklist'.
+  for (const std::string &F : Opts.SanitizerBlacklistFiles)
+    GenerateArg(Args, OPT_fsanitize_blacklist, F, SA);
+
+  if (Opts.getClangABICompat() == LangOptions::ClangABI::Ver3_8)
+    GenerateArg(Args, OPT_fclang_abi_compat_EQ, "3.8", SA);
+  else if (Opts.getClangABICompat() == LangOptions::ClangABI::Ver4)
+    GenerateArg(Args, OPT_fclang_abi_compat_EQ, "4.0", SA);
+  else if (Opts.getClangABICompat() == LangOptions::ClangABI::Ver6)
+    GenerateArg(Args, OPT_fclang_abi_compat_EQ, "6.0", SA);
+  else if (Opts.getClangABICompat() == LangOptions::ClangABI::Ver7)
+    GenerateArg(Args, OPT_fclang_abi_compat_EQ, "7.0", SA);
+  else if (Opts.getClangABICompat() == LangOptions::ClangABI::Ver9)
+    GenerateArg(Args, OPT_fclang_abi_compat_EQ, "9.0", SA);
+  else if (Opts.getClangABICompat() == LangOptions::ClangABI::Ver11)
+    GenerateArg(Args, OPT_fclang_abi_compat_EQ, "11.0", SA);
+
+  if (Opts.getSignReturnAddressScope() ==
+      LangOptions::SignReturnAddressScopeKind::All)
+    GenerateArg(Args, OPT_msign_return_address_EQ, "all", SA);
+  else if (Opts.getSignReturnAddressScope() ==
+           LangOptions::SignReturnAddressScopeKind::NonLeaf)
+    GenerateArg(Args, OPT_msign_return_address_EQ, "non-leaf", SA);
+
+  if (Opts.getSignReturnAddressKey() ==
+      LangOptions::SignReturnAddressKeyKind::BKey)
+    GenerateArg(Args, OPT_msign_return_address_key_EQ, "b_key", SA);
+}
+
+bool CompilerInvocation::ParseLangArgsImpl(LangOptions &Opts, ArgList &Args,
                                            InputKind IK, const llvm::Triple &T,
                                            std::vector<std::string> &Includes,
                                            DiagnosticsEngine &Diags) {
   unsigned NumErrorsBefore = Diags.getNumErrors();
 
   // FIXME: Cleanup per-file based stuff.
   LangStandard::Kind LangStd = LangStandard::lang_unspecified;
   if (const Arg *A = Args.getLastArg(OPT_std_EQ)) {
     LangStd = LangStandard::getLangKind(A->getValue());
     if (LangStd == LangStandard::lang_unspecified) {
       Diags.Report(diag::err_drv_invalid_value)
else {
       if (T.getArch() != llvm::Triple::x86)
         Diags.Report(diag::err_drv_argument_not_allowed_with)
             << A->getSpelling() << T.getTriple();
       else
         Opts.setDefaultCallingConv(LangOptions::DCC_StdCall);
     }
   }
 
+  // Check if -fopenmp is specified and set default version to 5.0.
+  Opts.OpenMP = Args.hasArg(OPT_fopenmp) ? 50 : 0;
   // Check if -fopenmp-simd is specified.
   bool IsSimdSpecified =
       Args.hasFlag(options::OPT_fopenmp_simd, options::OPT_fno_openmp_simd,
                    /*Default=*/false);
   Opts.OpenMPSimd = !Opts.OpenMP && IsSimdSpecified;
   Opts.OpenMPUseTLS =
       Opts.OpenMP && !Args.hasArg(options::OPT_fnoopenmp_use_tls);
   Opts.OpenMPIsDevice =
else if (Val == "fast-honor-pragmas")
       Opts.setDefaultFPContractMode(LangOptions::FPM_FastHonorPragmas);
     else
       Diags.Report(diag::err_drv_invalid_value) << A->getAsString(Args) << Val;
   }
 
   // Parse -fsanitize= arguments.
   parseSanitizerKinds("-fsanitize=", Args.getAllArgValues(OPT_fsanitize_EQ),
                       Diags, Opts.Sanitize);
+  Opts.SanitizerBlacklistFiles = Args.getAllArgValues(OPT_fsanitize_blacklist);
   std::vector<std::string> systemBlacklists =
       Args.getAllArgValues(OPT_fsanitize_system_blacklist);
   Opts.SanitizerBlacklistFiles.insert(Opts.SanitizerBlacklistFiles.end(),
                                       systemBlacklists.begin(),
                                       systemBlacklists.end());
 
   if (Arg *A = Args.getLastArg(OPT_fclang_abi_compat_EQ)) {
     Opts.setClangABICompat(LangOptions::ClangABI::Latest);
if (Arg *A = Args.getLastArg(OPT_msign_return_address_key_EQ)) {
               << A->getAsString(Args) << SignKey;
       }
     }
   }
 
   return Success && Diags.getNumErrors() == NumErrorsBefore;
 }
 
+bool CompilerInvocation::ParseLangArgs(CompilerInvocation &Res,
+                                       LangOptions &Opts,
+                                       llvm::opt::ArgList &Args, InputKind IK,
+                                       const llvm::Triple &T,
+                                       std::vector<std::string> &Includes,
+                                       DiagnosticsEngine &Diags) {
+  auto DummyOpts = std::make_shared<LangOptions>();
+
+  // We need to work around inconsistencies related to optimization flags. Their
+  // primary consumer is CodeGenOptions. However, the LangOptions parser also
+  // queries them, which means RoundTrip expects us to generate them. We don't
+  // want to do it in GenerateLangArgs, because it should eventually be the
+  // responsibility of GenerateCodeGenArgs. Until we start doing one big
+  // round-trip, let's do it here.
+  //
+  // Our parser always queries OPT_O_Group. When given -O1, -O2 or -O3, it also
+  // queries OPT_O. To ensure RoundTrip consistently considers us responsible
+  // for generating all of them, we ensure to proactively query them all.
+
+  return RoundTrip(
+      [IK, &T, &Includes](CompilerInvocation &Res, ArgList &Args,
+                          DiagnosticsEngine &Diags) {
+        // Proactively query all optimization flags.
+        Args.getLastArg(OPT_O0, OPT_O4, OPT_O, OPT_Ofast);
+        return ParseLangArgsImpl(*Res.getLangOpts(), Args, IK, T, Includes,
+                                 Diags);
+      },
+      [&T, &Args](CompilerInvocation &Res,
+                  SmallVectorImpl<const char *> &GenArgs, StringAllocator SA) {
+        GenerateLangArgs(*Res.getLangOpts(), GenArgs, SA, T);
+        // Generate all optimization flags we queried.
+        if (Arg *A = Args.getLastArg(OPT_O_Group)) {
+          OptSpecifier Opt = A->getOption().getID();
+
+          if (A->getNumValues() > 0)
+            GenerateArg(GenArgs, Opt, A->getValues().back(), SA);
+          else
+            GenerateArg(GenArgs, Opt, SA);
+        }
+
+        // We also queried -fcf-protection, but don't have enough information to
+        // generate it. Eventually, it will be generated from CodeGenOptions.
+        if (const Arg *A = Args.getLastArg(OPT_fcf_protection_EQ))
+          GenerateArg(GenArgs, OPT_fcf_protection_EQ, A->getValue(), SA);
+      },
+      [&DummyOpts](CompilerInvocation &Res) { Res.LangOpts.swap(DummyOpts); },
+      Res, Args, Diags, "LangOptions");
+}
+
 static bool isStrictlyPreprocessorAction(frontend::ActionKind Action) {
   switch (Action) {
   case frontend::ASTDeclList:
   case frontend::ASTDump:
   case frontend::ASTPrint:
   case frontend::ASTView:
   case frontend::EmitAssembly:
   case frontend::EmitBC:
if (DashX.getFormat() == InputKind::Precompiled ||
     // set regardless of the input type.
     LangOpts.PICLevel = getLastArgIntValue(Args, OPT_pic_level, 0, Diags);
     LangOpts.PIE = Args.hasArg(OPT_pic_is_pie);
     parseSanitizerKinds("-fsanitize=", Args.getAllArgValues(OPT_fsanitize_EQ),
                         Diags, LangOpts.Sanitize);
   } else {
     // Other LangOpts are only initialized when the input is not AST or LLVM IR.
     // FIXME: Should we really be calling this for an Language::Asm input?
-    Success &= ParseLangArgs(LangOpts, Args, DashX, T,
+    Success &= ParseLangArgs(Res, LangOpts, Args, DashX, T,
                              Res.getPreprocessorOpts().Includes, Diags);
     if (Res.getFrontendOpts().ProgramAction == frontend::RewriteObjC)
       LangOpts.ObjCExceptions = 1;
     if (T.isOSDarwin() && DashX.isPreprocessed()) {
       // Supress the darwin-specific 'stdlibcxx-not-found' diagnostic for
       // preprocessed input as we don't expect it to be used with -std=libc++
       // anyway.
       Res.getDiagnosticOpts().Warnings.push_back("no-stdlibcxx-not-found");
#define OPTION_WITH_MARSHALLING(                                               \
     DEFAULT_VALUE, IMPLIED_CHECK, IMPLIED_VALUE, NORMALIZER, DENORMALIZER,     \
     MERGER, EXTRACTOR, TABLE_INDEX)                                            \
   GENERATE_OPTION_WITH_MARSHALLING(Args, SA, KIND, FLAGS, SPELLING,            \
                                    ALWAYS_EMIT, this->KEYPATH, DEFAULT_VALUE,  \
                                    IMPLIED_CHECK, IMPLIED_VALUE, DENORMALIZER, \
                                    EXTRACTOR, TABLE_INDEX)
 
 #define DIAG_OPTION_WITH_MARSHALLING OPTION_WITH_MARSHALLING
-#define LANG_OPTION_WITH_MARSHALLING OPTION_WITH_MARSHALLING
 #define CODEGEN_OPTION_WITH_MARSHALLING OPTION_WITH_MARSHALLING
 
 #include "clang/Driver/Options.inc"
 
 #undef CODEGEN_OPTION_WITH_MARSHALLING
-#undef LANG_OPTION_WITH_MARSHALLING
 #undef DIAG_OPTION_WITH_MARSHALLING
 #undef OPTION_WITH_MARSHALLING
 
+  llvm::Triple T(TargetOpts->Triple);
+
   GeneratePreprocessorArgs(*PreprocessorOpts, Args, SA, *LangOpts,
                            FrontendOpts, CodeGenOpts);
   GenerateAnalyzerArgs(*AnalyzerOpts, Args, SA);
   GenerateHeaderSearchArgs(*HeaderSearchOpts, Args, SA);
-  GenerateLangArgs(*LangOpts, Args, SA);
+  GenerateLangArgs(*LangOpts, Args, SA,  T);
 }
 
 IntrusiveRefCntPtr<llvm::vfs::FileSystem>
 clang::createVFSFromCompilerInvocation(const CompilerInvocation &CI,
                                        DiagnosticsEngine &Diags) {
   return createVFSFromCompilerInvocation(CI, Diags,
                                          llvm::vfs::getRealFileSystem());
 }

clang/unittests/Basic/CMakeLists.txt

 set(LLVM_LINK_COMPONENTS
   Support
   )
 
 add_clang_unittest(BasicTests
   CharInfoTest.cpp
   DiagnosticTest.cpp
   FileEntryTest.cpp
   FileManagerTest.cpp
   LineOffsetMappingTest.cpp
+  SanitizersTest.cpp
   SourceManagerTest.cpp
   )
 
 clang_target_link_libraries(BasicTests
   PRIVATE
   clangAST
   clangBasic
   clangLex
   )

clang/unittests/Basic/SanitizersTest.cpp

+//===- unittests/Basic/SanitizersTest.cpp - Test Sanitizers ---------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Basic/Sanitizers.h"
+
+#include "gmock/gmock-matchers.h"
+#include "gtest/gtest.h"
+
+using namespace clang;
+
+using testing::Contains;
+using testing::Not;
+
+TEST(SanitizersTest, serializeSanitizers) {
+  SanitizerSet Set;
+  Set.set(parseSanitizerValue("memory", false), true);
+  Set.set(parseSanitizerValue("nullability-arg", false), true);
+
+  SmallVector<StringRef, 4> Serialized;
+  serializeSanitizerSet(Set, Serialized);
+
+  ASSERT_EQ(Serialized.size(), 2u);
+  ASSERT_THAT(Serialized, Contains("memory"));
+  ASSERT_THAT(Serialized, Contains("nullability-arg"));
+}
+
+TEST(SanitizersTest, serializeSanitizersIndividual) {
+  SanitizerSet Set;
+  Set.set(parseSanitizerValue("memory", false), true);
+  Set.set(parseSanitizerValue("nullability-arg", false), true);
+  Set.set(parseSanitizerValue("nullability-assign", false), true);
+  Set.set(parseSanitizerValue("nullability-return", false), true);
+
+  SmallVector<StringRef, 4> Serialized;
+  serializeSanitizerSet(Set, Serialized);
+
+  ASSERT_EQ(Serialized.size(), 4u);
+  ASSERT_THAT(Serialized, Contains("memory"));
+  ASSERT_THAT(Serialized, Contains("nullability-arg"));
+  ASSERT_THAT(Serialized, Contains("nullability-assign"));
+  ASSERT_THAT(Serialized, Contains("nullability-return"));
+  // Individual sanitizers don't get squashed into a single group.
+  ASSERT_THAT(Serialized, Not(Contains("nullability")));
+}