Update prebuilt Clang to r416183b from Android.

https://android.googlesource.com/platform/prebuilts/clang/host/
linux-x86/+/06a71ddac05c22edb2d10b590e1769b3f8619bef

clang 12.0.5 (based on r416183b) from build 7284624.

Change-Id: I277a316abcf47307562d8b748b84870f31a72866
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/linux-x64/clang/include/clang-tidy/ClangTidyCheck.h b/linux-x64/clang/include/clang-tidy/ClangTidyCheck.h
new file mode 100644
index 0000000..9fa0d63
--- /dev/null
+++ b/linux-x64/clang/include/clang-tidy/ClangTidyCheck.h
@@ -0,0 +1,580 @@
+//===--- ClangTidyCheck.h - clang-tidy --------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYCHECK_H
+
+#include "ClangTidyDiagnosticConsumer.h"
+#include "ClangTidyOptions.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/Basic/Diagnostic.h"
+#include "llvm/ADT/Optional.h"
+#include "llvm/Support/Error.h"
+#include <type_traits>
+#include <utility>
+#include <vector>
+
+namespace clang {
+
+class CompilerInstance;
+class SourceManager;
+
+namespace tidy {
+
+/// This class should be specialized by any enum type that needs to be converted
+/// to and from an \ref llvm::StringRef.
+template <class T> struct OptionEnumMapping {
+  // Specializations of this struct must implement this function.
+  static ArrayRef<std::pair<T, StringRef>> getEnumMapping() = delete;
+};
+
+template <typename T> class OptionError : public llvm::ErrorInfo<T> {
+  std::error_code convertToErrorCode() const override {
+    return llvm::inconvertibleErrorCode();
+  }
+
+public:
+  void log(raw_ostream &OS) const override { OS << this->message(); }
+};
+
+class MissingOptionError : public OptionError<MissingOptionError> {
+public:
+  explicit MissingOptionError(std::string OptionName)
+      : OptionName(OptionName) {}
+
+  std::string message() const override;
+  static char ID;
+private:
+  const std::string OptionName;
+};
+
+class UnparseableEnumOptionError
+    : public OptionError<UnparseableEnumOptionError> {
+public:
+  explicit UnparseableEnumOptionError(std::string LookupName,
+                                      std::string LookupValue)
+      : LookupName(LookupName), LookupValue(LookupValue) {}
+  explicit UnparseableEnumOptionError(std::string LookupName,
+                                      std::string LookupValue,
+                                      std::string SuggestedValue)
+      : LookupName(LookupName), LookupValue(LookupValue),
+        SuggestedValue(SuggestedValue) {}
+
+  std::string message() const override;
+  static char ID;
+
+private:
+  const std::string LookupName;
+  const std::string LookupValue;
+  const llvm::Optional<std::string> SuggestedValue;
+};
+
+class UnparseableIntegerOptionError
+    : public OptionError<UnparseableIntegerOptionError> {
+public:
+  explicit UnparseableIntegerOptionError(std::string LookupName,
+                                         std::string LookupValue,
+                                         bool IsBoolean = false)
+      : LookupName(LookupName), LookupValue(LookupValue), IsBoolean(IsBoolean) {
+  }
+
+  std::string message() const override;
+  static char ID;
+
+private:
+  const std::string LookupName;
+  const std::string LookupValue;
+  const bool IsBoolean;
+};
+
+/// Base class for all clang-tidy checks.
+///
+/// To implement a ``ClangTidyCheck``, write a subclass and override some of the
+/// base class's methods. E.g. to implement a check that validates namespace
+/// declarations, override ``registerMatchers``:
+///
+/// ~~~{.cpp}
+/// void registerMatchers(ast_matchers::MatchFinder *Finder) override {
+///   Finder->addMatcher(namespaceDecl().bind("namespace"), this);
+/// }
+/// ~~~
+///
+/// and then override ``check(const MatchResult &Result)`` to do the actual
+/// check for each match.
+///
+/// A new ``ClangTidyCheck`` instance is created per translation unit.
+///
+/// FIXME: Figure out whether carrying information from one TU to another is
+/// useful/necessary.
+class ClangTidyCheck : public ast_matchers::MatchFinder::MatchCallback {
+public:
+  /// Initializes the check with \p CheckName and \p Context.
+  ///
+  /// Derived classes must implement the constructor with this signature or
+  /// delegate it. If a check needs to read options, it can do this in the
+  /// constructor using the Options.get() methods below.
+  ClangTidyCheck(StringRef CheckName, ClangTidyContext *Context);
+
+  /// Override this to disable registering matchers and PP callbacks if an
+  /// invalid language version is being used.
+  ///
+  /// For example if a check is examining overloaded functions then this should
+  /// be overridden to return false when the CPlusPlus flag is not set in
+  /// \p LangOpts.
+  virtual bool isLanguageVersionSupported(const LangOptions &LangOpts) const {
+    return true;
+  }
+
+  /// Override this to register ``PPCallbacks`` in the preprocessor.
+  ///
+  /// This should be used for clang-tidy checks that analyze preprocessor-
+  /// dependent properties, e.g. include directives and macro definitions.
+  ///
+  /// This will only be executed if the function isLanguageVersionSupported
+  /// returns true.
+  ///
+  /// There are two Preprocessors to choose from that differ in how they handle
+  /// modular #includes:
+  ///  - PP is the real Preprocessor. It doesn't walk into modular #includes and
+  ///    thus doesn't generate PPCallbacks for their contents.
+  ///  - ModuleExpanderPP preprocesses the whole translation unit in the
+  ///    non-modular mode, which allows it to generate PPCallbacks not only for
+  ///    the main file and textual headers, but also for all transitively
+  ///    included modular headers when the analysis runs with modules enabled.
+  ///    When modules are not enabled ModuleExpanderPP just points to the real
+  ///    preprocessor.
+  virtual void registerPPCallbacks(const SourceManager &SM, Preprocessor *PP,
+                                   Preprocessor *ModuleExpanderPP) {}
+
+  /// Override this to register AST matchers with \p Finder.
+  ///
+  /// This should be used by clang-tidy checks that analyze code properties that
+  /// dependent on AST knowledge.
+  ///
+  /// You can register as many matchers as necessary with \p Finder. Usually,
+  /// "this" will be used as callback, but you can also specify other callback
+  /// classes. Thereby, different matchers can trigger different callbacks.
+  ///
+  /// This will only be executed if the function isLanguageVersionSupported
+  /// returns true.
+  ///
+  /// If you need to merge information between the different matchers, you can
+  /// store these as members of the derived class. However, note that all
+  /// matches occur in the order of the AST traversal.
+  virtual void registerMatchers(ast_matchers::MatchFinder *Finder) {}
+
+  /// ``ClangTidyChecks`` that register ASTMatchers should do the actual
+  /// work in here.
+  virtual void check(const ast_matchers::MatchFinder::MatchResult &Result) {}
+
+  /// Add a diagnostic with the check's name.
+  DiagnosticBuilder diag(SourceLocation Loc, StringRef Description,
+                         DiagnosticIDs::Level Level = DiagnosticIDs::Warning);
+
+  /// Add a diagnostic with the check's name.
+  DiagnosticBuilder diag(StringRef Description,
+                         DiagnosticIDs::Level Level = DiagnosticIDs::Warning);
+
+  /// Adds a diagnostic to report errors in the check's configuration.
+  DiagnosticBuilder
+  configurationDiag(StringRef Description,
+                    DiagnosticIDs::Level Level = DiagnosticIDs::Warning);
+
+  /// Should store all options supported by this check with their
+  /// current values or default values for options that haven't been overridden.
+  ///
+  /// The check should use ``Options.store()`` to store each option it supports
+  /// whether it has the default value or it has been overridden.
+  virtual void storeOptions(ClangTidyOptions::OptionMap &Options) {}
+
+  /// Provides access to the ``ClangTidyCheck`` options via check-local
+  /// names.
+  ///
+  /// Methods of this class prepend ``CheckName + "."`` to translate check-local
+  /// option names to global option names.
+  class OptionsView {
+  public:
+    /// Initializes the instance using \p CheckName + "." as a prefix.
+    OptionsView(StringRef CheckName,
+                const ClangTidyOptions::OptionMap &CheckOptions,
+                ClangTidyContext *Context);
+
+    /// Read a named option from the ``Context``.
+    ///
+    /// Reads the option with the check-local name \p LocalName from the
+    /// ``CheckOptions``. If the corresponding key is not present, returns
+    /// a ``MissingOptionError``.
+    llvm::Expected<std::string> get(StringRef LocalName) const;
+
+    /// Read a named option from the ``Context``.
+    ///
+    /// Reads the option with the check-local name \p LocalName from the
+    /// ``CheckOptions``. If the corresponding key is not present, returns
+    /// \p Default.
+    std::string get(StringRef LocalName, StringRef Default) const {
+      if (llvm::Expected<std::string> Val = get(LocalName))
+        return *Val;
+      else
+        llvm::consumeError(Val.takeError());
+      return Default.str();
+    }
+
+    /// Read a named option from the ``Context``.
+    ///
+    /// Reads the option with the check-local name \p LocalName from local or
+    /// global ``CheckOptions``. Gets local option first. If local is not
+    /// present, falls back to get global option. If global option is not
+    /// present either, returns a ``MissingOptionError``.
+    llvm::Expected<std::string> getLocalOrGlobal(StringRef LocalName) const;
+
+    /// Read a named option from the ``Context``.
+    ///
+    /// Reads the option with the check-local name \p LocalName from local or
+    /// global ``CheckOptions``. Gets local option first. If local is not
+    /// present, falls back to get global option. If global option is not
+    /// present either, returns \p Default.
+    std::string getLocalOrGlobal(StringRef LocalName, StringRef Default) const {
+      if (llvm::Expected<std::string> Val = getLocalOrGlobal(LocalName))
+        return *Val;
+      else
+        llvm::consumeError(Val.takeError());
+      return Default.str();
+    }
+
+    /// Read a named option from the ``Context`` and parse it as an
+    /// integral type ``T``.
+    ///
+    /// Reads the option with the check-local name \p LocalName from the
+    /// ``CheckOptions``. If the corresponding key is not present, returns
+    /// a ``MissingOptionError``. If the corresponding key can't be parsed as
+    /// a ``T``, return an ``UnparseableIntegerOptionError``.
+    template <typename T>
+    std::enable_if_t<std::is_integral<T>::value, llvm::Expected<T>>
+    get(StringRef LocalName) const {
+      if (llvm::Expected<std::string> Value = get(LocalName)) {
+        T Result{};
+        if (!StringRef(*Value).getAsInteger(10, Result))
+          return Result;
+        return llvm::make_error<UnparseableIntegerOptionError>(
+            (NamePrefix + LocalName).str(), *Value);
+      } else
+        return std::move(Value.takeError());
+    }
+
+    /// Read a named option from the ``Context`` and parse it as an
+    /// integral type ``T``.
+    ///
+    /// Reads the option with the check-local name \p LocalName from the
+    /// ``CheckOptions``. If the corresponding key is not present or it can't be
+    /// parsed as a ``T``, returns \p Default.
+    template <typename T>
+    std::enable_if_t<std::is_integral<T>::value, T> get(StringRef LocalName,
+                                                        T Default) const {
+      if (llvm::Expected<T> ValueOr = get<T>(LocalName))
+        return *ValueOr;
+      else
+        reportOptionParsingError(ValueOr.takeError());
+      return Default;
+    }
+
+    /// Read a named option from the ``Context`` and parse it as an
+    /// integral type ``T``.
+    ///
+    /// Reads the option with the check-local name \p LocalName from local or
+    /// global ``CheckOptions``. Gets local option first. If local is not
+    /// present, falls back to get global option. If global option is not
+    /// present either, returns a ``MissingOptionError``. If the corresponding
+    /// key can't be parsed as a ``T``, return an
+    /// ``UnparseableIntegerOptionError``.
+    template <typename T>
+    std::enable_if_t<std::is_integral<T>::value, llvm::Expected<T>>
+    getLocalOrGlobal(StringRef LocalName) const {
+      llvm::Expected<std::string> ValueOr = get(LocalName);
+      bool IsGlobal = false;
+      if (!ValueOr) {
+        IsGlobal = true;
+        llvm::consumeError(ValueOr.takeError());
+        ValueOr = getLocalOrGlobal(LocalName);
+        if (!ValueOr)
+          return std::move(ValueOr.takeError());
+      }
+      T Result{};
+      if (!StringRef(*ValueOr).getAsInteger(10, Result))
+        return Result;
+      return llvm::make_error<UnparseableIntegerOptionError>(
+          (IsGlobal ? LocalName.str() : (NamePrefix + LocalName).str()),
+          *ValueOr);
+    }
+
+    /// Read a named option from the ``Context`` and parse it as an
+    /// integral type ``T``.
+    ///
+    /// Reads the option with the check-local name \p LocalName from local or
+    /// global ``CheckOptions``. Gets local option first. If local is not
+    /// present, falls back to get global option. If global option is not
+    /// present either or it can't be parsed as a ``T``, returns \p Default.
+    template <typename T>
+    std::enable_if_t<std::is_integral<T>::value, T>
+    getLocalOrGlobal(StringRef LocalName, T Default) const {
+      if (llvm::Expected<T> ValueOr = getLocalOrGlobal<T>(LocalName))
+        return *ValueOr;
+      else
+        reportOptionParsingError(ValueOr.takeError());
+      return Default;
+    }
+
+    /// Read a named option from the ``Context`` and parse it as an
+    /// enum type ``T``.
+    ///
+    /// Reads the option with the check-local name \p LocalName from the
+    /// ``CheckOptions``. If the corresponding key is not present, returns a
+    /// ``MissingOptionError``. If the key can't be parsed as a ``T`` returns a
+    /// ``UnparseableEnumOptionError``.
+    ///
+    /// \ref clang::tidy::OptionEnumMapping must be specialized for ``T`` to
+    /// supply the mapping required to convert between ``T`` and a string.
+    template <typename T>
+    std::enable_if_t<std::is_enum<T>::value, llvm::Expected<T>>
+    get(StringRef LocalName, bool IgnoreCase = false) const {
+      if (llvm::Expected<int64_t> ValueOr =
+              getEnumInt(LocalName, typeEraseMapping<T>(), false, IgnoreCase))
+        return static_cast<T>(*ValueOr);
+      else
+        return std::move(ValueOr.takeError());
+    }
+
+    /// Read a named option from the ``Context`` and parse it as an
+    /// enum type ``T``.
+    ///
+    /// Reads the option with the check-local name \p LocalName from the
+    /// ``CheckOptions``. If the corresponding key is not present or it can't be
+    /// parsed as a ``T``, returns \p Default.
+    ///
+    /// \ref clang::tidy::OptionEnumMapping must be specialized for ``T`` to
+    /// supply the mapping required to convert between ``T`` and a string.
+    template <typename T>
+    std::enable_if_t<std::is_enum<T>::value, T>
+    get(StringRef LocalName, T Default, bool IgnoreCase = false) const {
+      if (auto ValueOr = get<T>(LocalName, IgnoreCase))
+        return *ValueOr;
+      else
+        reportOptionParsingError(ValueOr.takeError());
+      return Default;
+    }
+
+    /// Read a named option from the ``Context`` and parse it as an
+    /// enum type ``T``.
+    ///
+    /// Reads the option with the check-local name \p LocalName from local or
+    /// global ``CheckOptions``. Gets local option first. If local is not
+    /// present, falls back to get global option. If global option is not
+    /// present either, returns a ``MissingOptionError``. If the key can't be
+    /// parsed as a ``T`` returns a ``UnparseableEnumOptionError``.
+    ///
+    /// \ref clang::tidy::OptionEnumMapping must be specialized for ``T`` to
+    /// supply the mapping required to convert between ``T`` and a string.
+    template <typename T>
+    std::enable_if_t<std::is_enum<T>::value, llvm::Expected<T>>
+    getLocalOrGlobal(StringRef LocalName, bool IgnoreCase = false) const {
+      if (llvm::Expected<int64_t> ValueOr =
+              getEnumInt(LocalName, typeEraseMapping<T>(), true, IgnoreCase))
+        return static_cast<T>(*ValueOr);
+      else
+        return std::move(ValueOr.takeError());
+    }
+
+    /// Read a named option from the ``Context`` and parse it as an
+    /// enum type ``T``.
+    ///
+    /// Reads the option with the check-local name \p LocalName from local or
+    /// global ``CheckOptions``. Gets local option first. If local is not
+    /// present, falls back to get global option. If global option is not
+    /// present either or it can't be parsed as a ``T``, returns \p Default.
+    ///
+    /// \ref clang::tidy::OptionEnumMapping must be specialized for ``T`` to
+    /// supply the mapping required to convert between ``T`` and a string.
+    template <typename T>
+    std::enable_if_t<std::is_enum<T>::value, T>
+    getLocalOrGlobal(StringRef LocalName, T Default,
+                     bool IgnoreCase = false) const {
+      if (auto ValueOr = getLocalOrGlobal<T>(LocalName, IgnoreCase))
+        return *ValueOr;
+      else
+        reportOptionParsingError(ValueOr.takeError());
+      return Default;
+    }
+
+    /// Returns the value for the option \p LocalName represented as a ``T``.
+    /// If the option is missing returns None, if the option can't be parsed
+    /// as a ``T``, log that to stderr and return None.
+    template <typename T = std::string>
+    llvm::Optional<T> getOptional(StringRef LocalName) const {
+      if (auto ValueOr = get<T>(LocalName))
+        return *ValueOr;
+      else
+        reportOptionParsingError(ValueOr.takeError());
+      return llvm::None;
+    }
+
+    /// Returns the value for the local or global option \p LocalName
+    /// represented as a ``T``.
+    /// If the option is missing returns None, if the
+    /// option can't be parsed as a ``T``, log that to stderr and return None.
+    template <typename T = std::string>
+    llvm::Optional<T> getOptionalLocalOrGlobal(StringRef LocalName) const {
+      if (auto ValueOr = getLocalOrGlobal<T>(LocalName))
+        return *ValueOr;
+      else
+        reportOptionParsingError(ValueOr.takeError());
+      return llvm::None;
+    }
+
+    /// Stores an option with the check-local name \p LocalName with
+    /// string value \p Value to \p Options.
+    void store(ClangTidyOptions::OptionMap &Options, StringRef LocalName,
+               StringRef Value) const;
+
+    /// Stores an option with the check-local name \p LocalName with
+    /// integer value \p Value to \p Options.
+    template <typename T>
+    std::enable_if_t<std::is_integral<T>::value>
+    store(ClangTidyOptions::OptionMap &Options, StringRef LocalName,
+          T Value) const {
+      storeInt(Options, LocalName, Value);
+    }
+
+    /// Stores an option with the check-local name \p LocalName as the string
+    /// representation of the Enum \p Value to \p Options.
+    ///
+    /// \ref clang::tidy::OptionEnumMapping must be specialized for ``T`` to
+    /// supply the mapping required to convert between ``T`` and a string.
+    template <typename T>
+    std::enable_if_t<std::is_enum<T>::value>
+    store(ClangTidyOptions::OptionMap &Options, StringRef LocalName,
+          T Value) const {
+      ArrayRef<std::pair<T, StringRef>> Mapping =
+          OptionEnumMapping<T>::getEnumMapping();
+      auto Iter = llvm::find_if(
+          Mapping, [&](const std::pair<T, StringRef> &NameAndEnum) {
+            return NameAndEnum.first == Value;
+          });
+      assert(Iter != Mapping.end() && "Unknown Case Value");
+      store(Options, LocalName, Iter->second);
+    }
+
+  private:
+    using NameAndValue = std::pair<int64_t, StringRef>;
+
+    llvm::Expected<int64_t> getEnumInt(StringRef LocalName,
+                                       ArrayRef<NameAndValue> Mapping,
+                                       bool CheckGlobal, bool IgnoreCase) const;
+
+    template <typename T>
+    std::enable_if_t<std::is_enum<T>::value, std::vector<NameAndValue>>
+    typeEraseMapping() const {
+      ArrayRef<std::pair<T, StringRef>> Mapping =
+          OptionEnumMapping<T>::getEnumMapping();
+      std::vector<NameAndValue> Result;
+      Result.reserve(Mapping.size());
+      for (auto &MappedItem : Mapping) {
+        Result.emplace_back(static_cast<int64_t>(MappedItem.first),
+                            MappedItem.second);
+      }
+      return Result;
+    }
+
+    void storeInt(ClangTidyOptions::OptionMap &Options, StringRef LocalName,
+                  int64_t Value) const;
+
+    /// Emits a diagnostic if \p Err is not a MissingOptionError.
+    void reportOptionParsingError(llvm::Error &&Err) const;
+
+    std::string NamePrefix;
+    const ClangTidyOptions::OptionMap &CheckOptions;
+    ClangTidyContext *Context;
+  };
+
+private:
+  void run(const ast_matchers::MatchFinder::MatchResult &Result) override;
+  StringRef getID() const override { return CheckName; }
+  std::string CheckName;
+  ClangTidyContext *Context;
+
+protected:
+  OptionsView Options;
+  /// Returns the main file name of the current translation unit.
+  StringRef getCurrentMainFile() const { return Context->getCurrentFile(); }
+  /// Returns the language options from the context.
+  const LangOptions &getLangOpts() const { return Context->getLangOpts(); }
+};
+
+/// Read a named option from the ``Context`` and parse it as a bool.
+///
+/// Reads the option with the check-local name \p LocalName from the
+/// ``CheckOptions``. If the corresponding key is not present, returns
+/// a ``MissingOptionError``. If the corresponding key can't be parsed as
+/// a bool, return an ``UnparseableIntegerOptionError``.
+template <>
+llvm::Expected<bool>
+ClangTidyCheck::OptionsView::get<bool>(StringRef LocalName) const;
+
+/// Read a named option from the ``Context`` and parse it as a bool.
+///
+/// Reads the option with the check-local name \p LocalName from the
+/// ``CheckOptions``. If the corresponding key is not present or it can't be
+/// parsed as a bool, returns \p Default.
+template <>
+bool ClangTidyCheck::OptionsView::get<bool>(StringRef LocalName,
+                                            bool Default) const;
+
+/// Read a named option from the ``Context`` and parse it as a bool.
+///
+/// Reads the option with the check-local name \p LocalName from local or
+/// global ``CheckOptions``. Gets local option first. If local is not
+/// present, falls back to get global option. If global option is not
+/// present either, returns a ``MissingOptionError``. If the corresponding
+/// key can't be parsed as a bool, return an
+/// ``UnparseableIntegerOptionError``.
+template <>
+llvm::Expected<bool>
+ClangTidyCheck::OptionsView::getLocalOrGlobal<bool>(StringRef LocalName) const;
+
+/// Read a named option from the ``Context`` and parse it as a bool.
+///
+/// Reads the option with the check-local name \p LocalName from local or
+/// global ``CheckOptions``. Gets local option first. If local is not
+/// present, falls back to get global option. If global option is not
+/// present either or it can't be parsed as a bool, returns \p Default.
+template <>
+bool ClangTidyCheck::OptionsView::getLocalOrGlobal<bool>(StringRef LocalName,
+                                                         bool Default) const;
+
+/// Stores an option with the check-local name \p LocalName with
+/// bool value \p Value to \p Options.
+template <>
+void ClangTidyCheck::OptionsView::store<bool>(
+    ClangTidyOptions::OptionMap &Options, StringRef LocalName,
+    bool Value) const;
+
+/// Returns the value for the option \p LocalName.
+/// If the option is missing returns None.
+template <>
+Optional<std::string> ClangTidyCheck::OptionsView::getOptional<std::string>(
+    StringRef LocalName) const;
+
+/// Returns the value for the local or global option \p LocalName.
+/// If the option is missing returns None.
+template <>
+Optional<std::string>
+ClangTidyCheck::OptionsView::getOptionalLocalOrGlobal<std::string>(
+    StringRef LocalName) const;
+
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYCHECK_H