[clang] Move `ApplyHeaderSearchOptions` from Frontend to Lex

In D116750, the `clangFrontend` library was added as a dependency of `LexTests` in order to make `clang::ApplyHeaderSearchOptions()` available. This increased the number of TUs the test depends on.

This patch moves the function into `clangLex` and removes dependency of `LexTests` on `clangFrontend`.

Reviewed By: thakis

Differential Revision: https://reviews.llvm.org/D117024

1 files changed, 0 insertions, 687 deletions

diff --git a/clang/lib/Frontend/InitHeaderSearch.cpp b/clang/lib/Frontend/InitHeaderSearch.cpp
deleted file mode 100644
index 94ea7ba..0000000
--- a/clang/lib/Frontend/InitHeaderSearch.cpp
+++ /dev/null
@@ -1,687 +0,0 @@
-//===--- InitHeaderSearch.cpp - Initialize header search paths ------------===//
-//
-// 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 implements the InitHeaderSearch class.
-//
-//===----------------------------------------------------------------------===//
-
-#include "clang/Basic/FileManager.h"
-#include "clang/Basic/LangOptions.h"
-#include "clang/Config/config.h" // C_INCLUDE_DIRS
-#include "clang/Frontend/FrontendDiagnostic.h"
-#include "clang/Frontend/Utils.h"
-#include "clang/Lex/HeaderMap.h"
-#include "clang/Lex/HeaderSearch.h"
-#include "clang/Lex/HeaderSearchOptions.h"
-#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/SmallString.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/ADT/StringExtras.h"
-#include "llvm/ADT/Triple.h"
-#include "llvm/ADT/Twine.h"
-#include "llvm/Support/ErrorHandling.h"
-#include "llvm/Support/Path.h"
-#include "llvm/Support/raw_ostream.h"
-
-using namespace clang;
-using namespace clang::frontend;
-
-namespace {
-/// Holds information about a single DirectoryLookup object.
-struct DirectoryLookupInfo {
-  IncludeDirGroup Group;
-  DirectoryLookup Lookup;
-  Optional<unsigned> UserEntryIdx;
-
-  DirectoryLookupInfo(IncludeDirGroup Group, DirectoryLookup Lookup,
-                      Optional<unsigned> UserEntryIdx)
-      : Group(Group), Lookup(Lookup), UserEntryIdx(UserEntryIdx) {}
-};
-
-/// InitHeaderSearch - This class makes it easier to set the search paths of
-///  a HeaderSearch object. InitHeaderSearch stores several search path lists
-///  internally, which can be sent to a HeaderSearch object in one swoop.
-class InitHeaderSearch {
-  std::vector<DirectoryLookupInfo> IncludePath;
-  std::vector<std::pair<std::string, bool> > SystemHeaderPrefixes;
-  HeaderSearch &Headers;
-  bool Verbose;
-  std::string IncludeSysroot;
-  bool HasSysroot;
-
-public:
-  InitHeaderSearch(HeaderSearch &HS, bool verbose, StringRef sysroot)
-      : Headers(HS), Verbose(verbose), IncludeSysroot(std::string(sysroot)),
-        HasSysroot(!(sysroot.empty() || sysroot == "/")) {}
-
-  /// AddPath - Add the specified path to the specified group list, prefixing
-  /// the sysroot if used.
-  /// Returns true if the path exists, false if it was ignored.
-  bool AddPath(const Twine &Path, IncludeDirGroup Group, bool isFramework,
-               Optional<unsigned> UserEntryIdx = None);
-
-  /// AddUnmappedPath - Add the specified path to the specified group list,
-  /// without performing any sysroot remapping.
-  /// Returns true if the path exists, false if it was ignored.
-  bool AddUnmappedPath(const Twine &Path, IncludeDirGroup Group,
-                       bool isFramework,
-                       Optional<unsigned> UserEntryIdx = None);
-
-  /// AddSystemHeaderPrefix - Add the specified prefix to the system header
-  /// prefix list.
-  void AddSystemHeaderPrefix(StringRef Prefix, bool IsSystemHeader) {
-    SystemHeaderPrefixes.emplace_back(std::string(Prefix), IsSystemHeader);
-  }
-
-  /// AddGnuCPlusPlusIncludePaths - Add the necessary paths to support a gnu
-  ///  libstdc++.
-  /// Returns true if the \p Base path was found, false if it does not exist.
-  bool AddGnuCPlusPlusIncludePaths(StringRef Base, StringRef ArchDir,
-                                   StringRef Dir32, StringRef Dir64,
-                                   const llvm::Triple &triple);
-
-  /// AddMinGWCPlusPlusIncludePaths - Add the necessary paths to support a MinGW
-  ///  libstdc++.
-  void AddMinGWCPlusPlusIncludePaths(StringRef Base,
-                                     StringRef Arch,
-                                     StringRef Version);
-
-  // AddDefaultCIncludePaths - Add paths that should always be searched.
-  void AddDefaultCIncludePaths(const llvm::Triple &triple,
-                               const HeaderSearchOptions &HSOpts);
-
-  // AddDefaultCPlusPlusIncludePaths -  Add paths that should be searched when
-  //  compiling c++.
-  void AddDefaultCPlusPlusIncludePaths(const LangOptions &LangOpts,
-                                       const llvm::Triple &triple,
-                                       const HeaderSearchOptions &HSOpts);
-
-  /// AddDefaultSystemIncludePaths - Adds the default system include paths so
-  ///  that e.g. stdio.h is found.
-  void AddDefaultIncludePaths(const LangOptions &Lang,
-                              const llvm::Triple &triple,
-                              const HeaderSearchOptions &HSOpts);
-
-  /// Realize - Merges all search path lists into one list and send it to
-  /// HeaderSearch.
-  void Realize(const LangOptions &Lang);
-};
-
-}  // end anonymous namespace.
-
-static bool CanPrefixSysroot(StringRef Path) {
-#if defined(_WIN32)
-  return !Path.empty() && llvm::sys::path::is_separator(Path[0]);
-#else
-  return llvm::sys::path::is_absolute(Path);
-#endif
-}
-
-bool InitHeaderSearch::AddPath(const Twine &Path, IncludeDirGroup Group,
-                               bool isFramework,
-                               Optional<unsigned> UserEntryIdx) {
-  // Add the path with sysroot prepended, if desired and this is a system header
-  // group.
-  if (HasSysroot) {
-    SmallString<256> MappedPathStorage;
-    StringRef MappedPathStr = Path.toStringRef(MappedPathStorage);
-    if (CanPrefixSysroot(MappedPathStr)) {
-      return AddUnmappedPath(IncludeSysroot + Path, Group, isFramework,
-                             UserEntryIdx);
-    }
-  }
-
-  return AddUnmappedPath(Path, Group, isFramework, UserEntryIdx);
-}
-
-bool InitHeaderSearch::AddUnmappedPath(const Twine &Path, IncludeDirGroup Group,
-                                       bool isFramework,
-                                       Optional<unsigned> UserEntryIdx) {
-  assert(!Path.isTriviallyEmpty() && "can't handle empty path here");
-
-  FileManager &FM = Headers.getFileMgr();
-  SmallString<256> MappedPathStorage;
-  StringRef MappedPathStr = Path.toStringRef(MappedPathStorage);
-
-  // If use system headers while cross-compiling, emit the warning.
-  if (HasSysroot && (MappedPathStr.startswith("/usr/include") ||
-                     MappedPathStr.startswith("/usr/local/include"))) {
-    Headers.getDiags().Report(diag::warn_poison_system_directories)
-        << MappedPathStr;
-  }
-
-  // Compute the DirectoryLookup type.
-  SrcMgr::CharacteristicKind Type;
-  if (Group == Quoted || Group == Angled || Group == IndexHeaderMap) {
-    Type = SrcMgr::C_User;
-  } else if (Group == ExternCSystem) {
-    Type = SrcMgr::C_ExternCSystem;
-  } else {
-    Type = SrcMgr::C_System;
-  }
-
-  // If the directory exists, add it.
-  if (auto DE = FM.getOptionalDirectoryRef(MappedPathStr)) {
-    IncludePath.emplace_back(Group, DirectoryLookup(*DE, Type, isFramework),
-                             UserEntryIdx);
-    return true;
-  }
-
-  // Check to see if this is an apple-style headermap (which are not allowed to
-  // be frameworks).
-  if (!isFramework) {
-    if (auto FE = FM.getFile(MappedPathStr)) {
-      if (const HeaderMap *HM = Headers.CreateHeaderMap(*FE)) {
-        // It is a headermap, add it to the search path.
-        IncludePath.emplace_back(
-            Group, DirectoryLookup(HM, Type, Group == IndexHeaderMap),
-            UserEntryIdx);
-        return true;
-      }
-    }
-  }
-
-  if (Verbose)
-    llvm::errs() << "ignoring nonexistent directory \""
-                 << MappedPathStr << "\"\n";
-  return false;
-}
-
-bool InitHeaderSearch::AddGnuCPlusPlusIncludePaths(StringRef Base,
-                                                   StringRef ArchDir,
-                                                   StringRef Dir32,
-                                                   StringRef Dir64,
-                                                   const llvm::Triple &triple) {
-  // Add the base dir
-  bool IsBaseFound = AddPath(Base, CXXSystem, false);
-
-  // Add the multilib dirs
-  llvm::Triple::ArchType arch = triple.getArch();
-  bool is64bit = arch == llvm::Triple::ppc64 || arch == llvm::Triple::x86_64;
-  if (is64bit)
-    AddPath(Base + "/" + ArchDir + "/" + Dir64, CXXSystem, false);
-  else
-    AddPath(Base + "/" + ArchDir + "/" + Dir32, CXXSystem, false);
-
-  // Add the backward dir
-  AddPath(Base + "/backward", CXXSystem, false);
-  return IsBaseFound;
-}
-
-void InitHeaderSearch::AddMinGWCPlusPlusIncludePaths(StringRef Base,
-                                                     StringRef Arch,
-                                                     StringRef Version) {
-  AddPath(Base + "/" + Arch + "/" + Version + "/include/c++",
-          CXXSystem, false);
-  AddPath(Base + "/" + Arch + "/" + Version + "/include/c++/" + Arch,
-          CXXSystem, false);
-  AddPath(Base + "/" + Arch + "/" + Version + "/include/c++/backward",
-          CXXSystem, false);
-}
-
-void InitHeaderSearch::AddDefaultCIncludePaths(const llvm::Triple &triple,
-                                            const HeaderSearchOptions &HSOpts) {
-  llvm::Triple::OSType os = triple.getOS();
-
-  if (triple.isOSDarwin()) {
-    llvm_unreachable("Include management is handled in the driver.");
-  }
-
-  if (HSOpts.UseStandardSystemIncludes) {
-    switch (os) {
-    case llvm::Triple::CloudABI:
-    case llvm::Triple::FreeBSD:
-    case llvm::Triple::NetBSD:
-    case llvm::Triple::OpenBSD:
-    case llvm::Triple::NaCl:
-    case llvm::Triple::PS4:
-    case llvm::Triple::ELFIAMCU:
-    case llvm::Triple::Fuchsia:
-      break;
-    case llvm::Triple::Win32:
-      if (triple.getEnvironment() != llvm::Triple::Cygnus)
-        break;
-      LLVM_FALLTHROUGH;
-    default:
-      // FIXME: temporary hack: hard-coded paths.
-      AddPath("/usr/local/include", System, false);
-      break;
-    }
-  }
-
-  // Builtin includes use #include_next directives and should be positioned
-  // just prior C include dirs.
-  if (HSOpts.UseBuiltinIncludes) {
-    // Ignore the sys root, we *always* look for clang headers relative to
-    // supplied path.
-    SmallString<128> P = StringRef(HSOpts.ResourceDir);
-    llvm::sys::path::append(P, "include");
-    AddUnmappedPath(P, ExternCSystem, false);
-  }
-
-  // All remaining additions are for system include directories, early exit if
-  // we aren't using them.
-  if (!HSOpts.UseStandardSystemIncludes)
-    return;
-
-  // Add dirs specified via 'configure --with-c-include-dirs'.
-  StringRef CIncludeDirs(C_INCLUDE_DIRS);
-  if (CIncludeDirs != "") {
-    SmallVector<StringRef, 5> dirs;
-    CIncludeDirs.split(dirs, ":");
-    for (StringRef dir : dirs)
-      AddPath(dir, ExternCSystem, false);
-    return;
-  }
-
-  switch (os) {
-  case llvm::Triple::Linux:
-  case llvm::Triple::Hurd:
-  case llvm::Triple::Solaris:
-  case llvm::Triple::OpenBSD:
-    llvm_unreachable("Include management is handled in the driver.");
-
-  case llvm::Triple::CloudABI: {
-    // <sysroot>/<triple>/include
-    SmallString<128> P = StringRef(HSOpts.ResourceDir);
-    llvm::sys::path::append(P, "../../..", triple.str(), "include");
-    AddPath(P, System, false);
-    break;
-  }
-
-  case llvm::Triple::Haiku:
-    AddPath("/boot/system/non-packaged/develop/headers", System, false);
-    AddPath("/boot/system/develop/headers/os", System, false);
-    AddPath("/boot/system/develop/headers/os/app", System, false);
-    AddPath("/boot/system/develop/headers/os/arch", System, false);
-    AddPath("/boot/system/develop/headers/os/device", System, false);
-    AddPath("/boot/system/develop/headers/os/drivers", System, false);
-    AddPath("/boot/system/develop/headers/os/game", System, false);
-    AddPath("/boot/system/develop/headers/os/interface", System, false);
-    AddPath("/boot/system/develop/headers/os/kernel", System, false);
-    AddPath("/boot/system/develop/headers/os/locale", System, false);
-    AddPath("/boot/system/develop/headers/os/mail", System, false);
-    AddPath("/boot/system/develop/headers/os/media", System, false);
-    AddPath("/boot/system/develop/headers/os/midi", System, false);
-    AddPath("/boot/system/develop/headers/os/midi2", System, false);
-    AddPath("/boot/system/develop/headers/os/net", System, false);
-    AddPath("/boot/system/develop/headers/os/opengl", System, false);
-    AddPath("/boot/system/develop/headers/os/storage", System, false);
-    AddPath("/boot/system/develop/headers/os/support", System, false);
-    AddPath("/boot/system/develop/headers/os/translation", System, false);
-    AddPath("/boot/system/develop/headers/os/add-ons/graphics", System, false);
-    AddPath("/boot/system/develop/headers/os/add-ons/input_server", System, false);
-    AddPath("/boot/system/develop/headers/os/add-ons/mail_daemon", System, false);
-    AddPath("/boot/system/develop/headers/os/add-ons/registrar", System, false);
-    AddPath("/boot/system/develop/headers/os/add-ons/screen_saver", System, false);
-    AddPath("/boot/system/develop/headers/os/add-ons/tracker", System, false);
-    AddPath("/boot/system/develop/headers/os/be_apps/Deskbar", System, false);
-    AddPath("/boot/system/develop/headers/os/be_apps/NetPositive", System, false);
-    AddPath("/boot/system/develop/headers/os/be_apps/Tracker", System, false);
-    AddPath("/boot/system/develop/headers/3rdparty", System, false);
-    AddPath("/boot/system/develop/headers/bsd", System, false);
-    AddPath("/boot/system/develop/headers/glibc", System, false);
-    AddPath("/boot/system/develop/headers/posix", System, false);
-    AddPath("/boot/system/develop/headers",  System, false);
-    break;
-  case llvm::Triple::RTEMS:
-    break;
-  case llvm::Triple::Win32:
-    switch (triple.getEnvironment()) {
-    default: llvm_unreachable("Include management is handled in the driver.");
-    case llvm::Triple::Cygnus:
-      AddPath("/usr/include/w32api", System, false);
-      break;
-    case llvm::Triple::GNU:
-      break;
-    }
-    break;
-  default:
-    break;
-  }
-
-  switch (os) {
-  case llvm::Triple::CloudABI:
-  case llvm::Triple::RTEMS:
-  case llvm::Triple::NaCl:
-  case llvm::Triple::ELFIAMCU:
-  case llvm::Triple::Fuchsia:
-    break;
-  case llvm::Triple::PS4: {
-    // <isysroot> gets prepended later in AddPath().
-    std::string BaseSDKPath;
-    if (!HasSysroot) {
-      const char *envValue = getenv("SCE_ORBIS_SDK_DIR");
-      if (envValue)
-        BaseSDKPath = envValue;
-      else {
-        // HSOpts.ResourceDir variable contains the location of Clang's
-        // resource files.
-        // Assuming that Clang is configured for PS4 without
-        // --with-clang-resource-dir option, the location of Clang's resource
-        // files is <SDK_DIR>/host_tools/lib/clang
-        SmallString<128> P = StringRef(HSOpts.ResourceDir);
-        llvm::sys::path::append(P, "../../..");
-        BaseSDKPath = std::string(P.str());
-      }
-    }
-    AddPath(BaseSDKPath + "/target/include", System, false);
-    if (triple.isPS4CPU())
-      AddPath(BaseSDKPath + "/target/include_common", System, false);
-    LLVM_FALLTHROUGH;
-  }
-  default:
-    AddPath("/usr/include", ExternCSystem, false);
-    break;
-  }
-}
-
-void InitHeaderSearch::AddDefaultCPlusPlusIncludePaths(
-    const LangOptions &LangOpts, const llvm::Triple &triple,
-    const HeaderSearchOptions &HSOpts) {
-  llvm::Triple::OSType os = triple.getOS();
-  // FIXME: temporary hack: hard-coded paths.
-
-  if (triple.isOSDarwin()) {
-    llvm_unreachable("Include management is handled in the driver.");
-  }
-
-  switch (os) {
-  case llvm::Triple::Linux:
-  case llvm::Triple::Hurd:
-  case llvm::Triple::Solaris:
-  case llvm::Triple::AIX:
-    llvm_unreachable("Include management is handled in the driver.");
-    break;
-  case llvm::Triple::Win32:
-    switch (triple.getEnvironment()) {
-    default: llvm_unreachable("Include management is handled in the driver.");
-    case llvm::Triple::Cygnus:
-      // Cygwin-1.7
-      AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.7.3");
-      AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.5.3");
-      AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.3.4");
-      // g++-4 / Cygwin-1.5
-      AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.3.2");
-      break;
-    }
-    break;
-  case llvm::Triple::DragonFly:
-    AddPath("/usr/include/c++/5.0", CXXSystem, false);
-    break;
-  case llvm::Triple::Minix:
-    AddGnuCPlusPlusIncludePaths("/usr/gnu/include/c++/4.4.3",
-                                "", "", "", triple);
-    break;
-  default:
-    break;
-  }
-}
-
-void InitHeaderSearch::AddDefaultIncludePaths(const LangOptions &Lang,
-                                              const llvm::Triple &triple,
-                                            const HeaderSearchOptions &HSOpts) {
-  // NB: This code path is going away. All of the logic is moving into the
-  // driver which has the information necessary to do target-specific
-  // selections of default include paths. Each target which moves there will be
-  // exempted from this logic here until we can delete the entire pile of code.
-  switch (triple.getOS()) {
-  default:
-    break; // Everything else continues to use this routine's logic.
-
-  case llvm::Triple::Emscripten:
-  case llvm::Triple::Linux:
-  case llvm::Triple::Hurd:
-  case llvm::Triple::OpenBSD:
-  case llvm::Triple::Solaris:
-  case llvm::Triple::WASI:
-  case llvm::Triple::AIX:
-    return;
-
-  case llvm::Triple::Win32:
-    if (triple.getEnvironment() != llvm::Triple::Cygnus ||
-        triple.isOSBinFormatMachO())
-      return;
-    break;
-
-  case llvm::Triple::UnknownOS:
-    if (triple.isWasm())
-      return;
-    break;
-  }
-
-  // All header search logic is handled in the Driver for Darwin.
-  if (triple.isOSDarwin()) {
-    if (HSOpts.UseStandardSystemIncludes) {
-      // Add the default framework include paths on Darwin.
-      AddPath("/System/Library/Frameworks", System, true);
-      AddPath("/Library/Frameworks", System, true);
-    }
-    return;
-  }
-
-  if (Lang.CPlusPlus && !Lang.AsmPreprocessor &&
-      HSOpts.UseStandardCXXIncludes && HSOpts.UseStandardSystemIncludes) {
-    if (HSOpts.UseLibcxx) {
-      AddPath("/usr/include/c++/v1", CXXSystem, false);
-    } else {
-      AddDefaultCPlusPlusIncludePaths(Lang, triple, HSOpts);
-    }
-  }
-
-  AddDefaultCIncludePaths(triple, HSOpts);
-}
-
-/// RemoveDuplicates - If there are duplicate directory entries in the specified
-/// search list, remove the later (dead) ones.  Returns the number of non-system
-/// headers removed, which is used to update NumAngled.
-static unsigned RemoveDuplicates(std::vector<DirectoryLookupInfo> &SearchList,
-                                 unsigned First, bool Verbose) {
-  llvm::SmallPtrSet<const DirectoryEntry *, 8> SeenDirs;
-  llvm::SmallPtrSet<const DirectoryEntry *, 8> SeenFrameworkDirs;
-  llvm::SmallPtrSet<const HeaderMap *, 8> SeenHeaderMaps;
-  unsigned NonSystemRemoved = 0;
-  for (unsigned i = First; i != SearchList.size(); ++i) {
-    unsigned DirToRemove = i;
-
-    const DirectoryLookup &CurEntry = SearchList[i].Lookup;
-
-    if (CurEntry.isNormalDir()) {
-      // If this isn't the first time we've seen this dir, remove it.
-      if (SeenDirs.insert(CurEntry.getDir()).second)
-        continue;
-    } else if (CurEntry.isFramework()) {
-      // If this isn't the first time we've seen this framework dir, remove it.
-      if (SeenFrameworkDirs.insert(CurEntry.getFrameworkDir()).second)
-        continue;
-    } else {
-      assert(CurEntry.isHeaderMap() && "Not a headermap or normal dir?");
-      // If this isn't the first time we've seen this headermap, remove it.
-      if (SeenHeaderMaps.insert(CurEntry.getHeaderMap()).second)
-        continue;
-    }
-
-    // If we have a normal #include dir/framework/headermap that is shadowed
-    // later in the chain by a system include location, we actually want to
-    // ignore the user's request and drop the user dir... keeping the system
-    // dir.  This is weird, but required to emulate GCC's search path correctly.
-    //
-    // Since dupes of system dirs are rare, just rescan to find the original
-    // that we're nuking instead of using a DenseMap.
-    if (CurEntry.getDirCharacteristic() != SrcMgr::C_User) {
-      // Find the dir that this is the same of.
-      unsigned FirstDir;
-      for (FirstDir = First;; ++FirstDir) {
-        assert(FirstDir != i && "Didn't find dupe?");
-
-        const DirectoryLookup &SearchEntry = SearchList[FirstDir].Lookup;
-
-        // If these are different lookup types, then they can't be the dupe.
-        if (SearchEntry.getLookupType() != CurEntry.getLookupType())
-          continue;
-
-        bool isSame;
-        if (CurEntry.isNormalDir())
-          isSame = SearchEntry.getDir() == CurEntry.getDir();
-        else if (CurEntry.isFramework())
-          isSame = SearchEntry.getFrameworkDir() == CurEntry.getFrameworkDir();
-        else {
-          assert(CurEntry.isHeaderMap() && "Not a headermap or normal dir?");
-          isSame = SearchEntry.getHeaderMap() == CurEntry.getHeaderMap();
-        }
-
-        if (isSame)
-          break;
-      }
-
-      // If the first dir in the search path is a non-system dir, zap it
-      // instead of the system one.
-      if (SearchList[FirstDir].Lookup.getDirCharacteristic() == SrcMgr::C_User)
-        DirToRemove = FirstDir;
-    }
-
-    if (Verbose) {
-      llvm::errs() << "ignoring duplicate directory \""
-                   << CurEntry.getName() << "\"\n";
-      if (DirToRemove != i)
-        llvm::errs() << "  as it is a non-system directory that duplicates "
-                     << "a system directory\n";
-    }
-    if (DirToRemove != i)
-      ++NonSystemRemoved;
-
-    // This is reached if the current entry is a duplicate.  Remove the
-    // DirToRemove (usually the current dir).
-    SearchList.erase(SearchList.begin()+DirToRemove);
-    --i;
-  }
-  return NonSystemRemoved;
-}
-
-/// Extract DirectoryLookups from DirectoryLookupInfos.
-static std::vector<DirectoryLookup>
-extractLookups(const std::vector<DirectoryLookupInfo> &Infos) {
-  std::vector<DirectoryLookup> Lookups;
-  Lookups.reserve(Infos.size());
-  llvm::transform(Infos, std::back_inserter(Lookups),
-                  [](const DirectoryLookupInfo &Info) { return Info.Lookup; });
-  return Lookups;
-}
-
-/// Collect the mapping between indices of DirectoryLookups and UserEntries.
-static llvm::DenseMap<unsigned, unsigned>
-mapToUserEntries(const std::vector<DirectoryLookupInfo> &Infos) {
-  llvm::DenseMap<unsigned, unsigned> LookupsToUserEntries;
-  for (unsigned I = 0, E = Infos.size(); I < E; ++I) {
-    // Check whether this DirectoryLookup maps to a HeaderSearch::UserEntry.
-    if (Infos[I].UserEntryIdx)
-      LookupsToUserEntries.insert({I, *Infos[I].UserEntryIdx});
-  }
-  return LookupsToUserEntries;
-}
-
-void InitHeaderSearch::Realize(const LangOptions &Lang) {
-  // Concatenate ANGLE+SYSTEM+AFTER chains together into SearchList.
-  std::vector<DirectoryLookupInfo> SearchList;
-  SearchList.reserve(IncludePath.size());
-
-  // Quoted arguments go first.
-  for (auto &Include : IncludePath)
-    if (Include.Group == Quoted)
-      SearchList.push_back(Include);
-
-  // Deduplicate and remember index.
-  RemoveDuplicates(SearchList, 0, Verbose);
-  unsigned NumQuoted = SearchList.size();
-
-  for (auto &Include : IncludePath)
-    if (Include.Group == Angled || Include.Group == IndexHeaderMap)
-      SearchList.push_back(Include);
-
-  RemoveDuplicates(SearchList, NumQuoted, Verbose);
-  unsigned NumAngled = SearchList.size();
-
-  for (auto &Include : IncludePath)
-    if (Include.Group == System || Include.Group == ExternCSystem ||
-        (!Lang.ObjC && !Lang.CPlusPlus && Include.Group == CSystem) ||
-        (/*FIXME !Lang.ObjC && */ Lang.CPlusPlus &&
-         Include.Group == CXXSystem) ||
-        (Lang.ObjC && !Lang.CPlusPlus && Include.Group == ObjCSystem) ||
-        (Lang.ObjC && Lang.CPlusPlus && Include.Group == ObjCXXSystem))
-      SearchList.push_back(Include);
-
-  for (auto &Include : IncludePath)
-    if (Include.Group == After)
-      SearchList.push_back(Include);
-
-  // Remove duplicates across both the Angled and System directories.  GCC does
-  // this and failing to remove duplicates across these two groups breaks
-  // #include_next.
-  unsigned NonSystemRemoved = RemoveDuplicates(SearchList, NumQuoted, Verbose);
-  NumAngled -= NonSystemRemoved;
-
-  bool DontSearchCurDir = false;  // TODO: set to true if -I- is set?
-  Headers.SetSearchPaths(extractLookups(SearchList), NumQuoted, NumAngled,
-                         DontSearchCurDir, mapToUserEntries(SearchList));
-
-  Headers.SetSystemHeaderPrefixes(SystemHeaderPrefixes);
-
-  // If verbose, print the list of directories that will be searched.
-  if (Verbose) {
-    llvm::errs() << "#include \"...\" search starts here:\n";
-    for (unsigned i = 0, e = SearchList.size(); i != e; ++i) {
-      if (i == NumQuoted)
-        llvm::errs() << "#include <...> search starts here:\n";
-      StringRef Name = SearchList[i].Lookup.getName();
-      const char *Suffix;
-      if (SearchList[i].Lookup.isNormalDir())
-        Suffix = "";
-      else if (SearchList[i].Lookup.isFramework())
-        Suffix = " (framework directory)";
-      else {
-        assert(SearchList[i].Lookup.isHeaderMap() && "Unknown DirectoryLookup");
-        Suffix = " (headermap)";
-      }
-      llvm::errs() << " " << Name << Suffix << "\n";
-    }
-    llvm::errs() << "End of search list.\n";
-  }
-}
-
-void clang::ApplyHeaderSearchOptions(HeaderSearch &HS,
-                                     const HeaderSearchOptions &HSOpts,
-                                     const LangOptions &Lang,
-                                     const llvm::Triple &Triple) {
-  InitHeaderSearch Init(HS, HSOpts.Verbose, HSOpts.Sysroot);
-
-  // Add the user defined entries.
-  for (unsigned i = 0, e = HSOpts.UserEntries.size(); i != e; ++i) {
-    const HeaderSearchOptions::Entry &E = HSOpts.UserEntries[i];
-    if (E.IgnoreSysRoot) {
-      Init.AddUnmappedPath(E.Path, E.Group, E.IsFramework, i);
-    } else {
-      Init.AddPath(E.Path, E.Group, E.IsFramework, i);
-    }
-  }
-
-  Init.AddDefaultIncludePaths(Lang, Triple, HSOpts);
-
-  for (unsigned i = 0, e = HSOpts.SystemHeaderPrefixes.size(); i != e; ++i)
-    Init.AddSystemHeaderPrefix(HSOpts.SystemHeaderPrefixes[i].Prefix,
-                               HSOpts.SystemHeaderPrefixes[i].IsSystemHeader);
-
-  if (HSOpts.UseBuiltinIncludes) {
-    // Set up the builtin include directory in the module map.
-    SmallString<128> P = StringRef(HSOpts.ResourceDir);
-    llvm::sys::path::append(P, "include");
-    if (auto Dir = HS.getFileMgr().getDirectory(P))
-      HS.getModuleMap().setBuiltinIncludeDir(*Dir);
-  }
-
-  Init.Realize(Lang);
-}