C++ SmallString::append方法代码示例

ErrorOr<StringRef> ELFLinkingContext::searchFile(StringRef fileName,
                                                 bool isSysRooted) const {
  SmallString<128> path;
  if (is_absolute(fileName) && isSysRooted) {
    path.assign(_sysrootPath);
    path.append(fileName);
    if (exists(path.str()))
      return path.str().copy(_allocator);
  } else if (exists(fileName)) {
    return fileName;
  }

  if (is_absolute(fileName))
    return make_error_code(llvm::errc::no_such_file_or_directory);

  for (StringRef dir : _inputSearchPaths) {
    buildSearchPath(path, dir, _sysrootPath);
    llvm::sys::path::append(path, fileName);
    if (exists(path.str()))
      return path.str().copy(_allocator);
  }
  return make_error_code(llvm::errc::no_such_file_or_directory);
}

std::string CoveragePrinter::getOutputPath(StringRef Path, StringRef Extension,
                                           bool InToplevel,
                                           bool Relative) const {
  assert(Extension.size() && "The file extension may not be empty");

  SmallString<256> FullPath;

  if (!Relative)
    FullPath.append(Opts.ShowOutputDirectory);

  if (!InToplevel)
    sys::path::append(FullPath, getCoverageDir());

  SmallString<256> ParentPath = sys::path::parent_path(Path);
  sys::path::remove_dots(ParentPath, /*remove_dot_dots=*/true);
  sys::path::append(FullPath, sys::path::relative_path(ParentPath));

  auto PathFilename = (sys::path::filename(Path) + "." + Extension).str();
  sys::path::append(FullPath, PathFilename);
  sys::path::native(FullPath);

  return FullPath.str();
}

void native(SmallVectorImpl<char> &Path, Style style) {
  if (Path.empty())
    return;
  if (real_style(style) == Style::windows) {
    std::replace(Path.begin(), Path.end(), '/', '\\');
    if (Path[0] == '~' && (Path.size() == 1 || is_separator(Path[1], style))) {
      SmallString<128> PathHome;
      home_directory(PathHome);
      PathHome.append(Path.begin() + 1, Path.end());
      Path = PathHome;
    }
  } else {
    for (auto PI = Path.begin(), PE = Path.end(); PI < PE; ++PI) {
      if (*PI == '\\') {
        auto PN = PI + 1;
        if (PN < PE && *PN == '\\')
          ++PI; // increment once, the for loop will move over the escaped slash
        else
          *PI = '/';
      }
    }
  }
}

TEST(DeclPrinter, TestCXXMethodDecl_Operator2) {
  const char *OperatorNames[] = {
    "~", "!", "++", "--", "->"
  };

  for (unsigned i = 0, e = llvm::array_lengthof(OperatorNames); i != e; ++i) {
    SmallString<128> Code;
    Code.append("struct Z { void operator");
    Code.append(OperatorNames[i]);
    Code.append("(); };");

    SmallString<128> Expected;
    Expected.append("void operator");
    Expected.append(OperatorNames[i]);
    Expected.append("()");
    // Should be: with semicolon

    ASSERT_TRUE(PrintedDeclCXX98Matches(
      Code,
      methodDecl(ofClass(hasName("Z"))).bind("id"),
      Expected));
  }
}

/// LookupFile - Given a "foo" or \<foo> reference, look up the indicated file,
/// return null on failure.  isAngled indicates whether the file reference is
/// for system \#include's or not (i.e. using <> instead of ""). Includers, if
/// non-empty, indicates where the \#including file(s) are, in case a relative
/// search is needed. Microsoft mode will pass all \#including files.
const FileEntry *HeaderSearch::LookupFile(
    StringRef Filename, SourceLocation IncludeLoc, bool isAngled,
    const DirectoryLookup *FromDir, const DirectoryLookup *&CurDir,
    ArrayRef<std::pair<const FileEntry *, const DirectoryEntry *>> Includers,
    SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath,
    ModuleMap::KnownHeader *SuggestedModule, bool SkipCache) {
  if (SuggestedModule)
    *SuggestedModule = ModuleMap::KnownHeader();

  // If 'Filename' is absolute, check to see if it exists and no searching.
  if (llvm::sys::path::is_absolute(Filename)) {
    CurDir = nullptr;

    // If this was an #include_next "/absolute/file", fail.
    if (FromDir) return nullptr;

    if (SearchPath)
      SearchPath->clear();
    if (RelativePath) {
      RelativePath->clear();
      RelativePath->append(Filename.begin(), Filename.end());
    }
    // Otherwise, just return the file.
    return FileMgr.getFile(Filename, /*openFile=*/true);
  }

  // This is the header that MSVC's header search would have found.
  const FileEntry *MSFE = nullptr;
  ModuleMap::KnownHeader MSSuggestedModule;

  // Unless disabled, check to see if the file is in the #includer's
  // directory.  This cannot be based on CurDir, because each includer could be
  // a #include of a subdirectory (#include "foo/bar.h") and a subsequent
  // include of "baz.h" should resolve to "whatever/foo/baz.h".
  // This search is not done for <> headers.
  if (!Includers.empty() && !isAngled && !NoCurDirSearch) {
    SmallString<1024> TmpDir;
    bool First = true;
    for (const auto &IncluderAndDir : Includers) {
      const FileEntry *Includer = IncluderAndDir.first;

      // Concatenate the requested file onto the directory.
      // FIXME: Portability.  Filename concatenation should be in sys::Path.
      TmpDir = IncluderAndDir.second->getName();
      TmpDir.push_back('/');
      TmpDir.append(Filename.begin(), Filename.end());

      // FIXME: We don't cache the result of getFileInfo across the call to
      // getFileAndSuggestModule, because it's a reference to an element of
      // a container that could be reallocated across this call.
      //
      // FIXME: If we have no includer, that means we're processing a #include
      // from a module build. We should treat this as a system header if we're
      // building a [system] module.
      bool IncluderIsSystemHeader =
          Includer && getFileInfo(Includer).DirInfo != SrcMgr::C_User;
      if (const FileEntry *FE = getFileAndSuggestModule(
              *this, TmpDir.str(), IncluderAndDir.second,
              IncluderIsSystemHeader, SuggestedModule)) {
        if (!Includer) {
          assert(First && "only first includer can have no file");
          return FE;
        }

        // Leave CurDir unset.
        // This file is a system header or C++ unfriendly if the old file is.
        //
        // Note that we only use one of FromHFI/ToHFI at once, due to potential
        // reallocation of the underlying vector potentially making the first
        // reference binding dangling.
        HeaderFileInfo &FromHFI = getFileInfo(Includer);
        unsigned DirInfo = FromHFI.DirInfo;
        bool IndexHeaderMapHeader = FromHFI.IndexHeaderMapHeader;
        StringRef Framework = FromHFI.Framework;

        HeaderFileInfo &ToHFI = getFileInfo(FE);
        ToHFI.DirInfo = DirInfo;
        ToHFI.IndexHeaderMapHeader = IndexHeaderMapHeader;
        ToHFI.Framework = Framework;

        if (SearchPath) {
          StringRef SearchPathRef(IncluderAndDir.second->getName());
          SearchPath->clear();
          SearchPath->append(SearchPathRef.begin(), SearchPathRef.end());
        }
        if (RelativePath) {
          RelativePath->clear();
          RelativePath->append(Filename.begin(), Filename.end());
        }
        if (First)
          return FE;

        // Otherwise, we found the path via MSVC header search rules.  If
        // -Wmsvc-include is enabled, we have to keep searching to see if we
        // would've found this header in -I or -isystem directories.
//.........这里部分代码省略.........

/// DoFrameworkLookup - Do a lookup of the specified file in the current
/// DirectoryLookup, which is a framework directory.
const FileEntry *DirectoryLookup::DoFrameworkLookup(
    StringRef Filename,
    HeaderSearch &HS,
    SmallVectorImpl<char> *SearchPath,
    SmallVectorImpl<char> *RelativePath,
    ModuleMap::KnownHeader *SuggestedModule,
    bool &InUserSpecifiedSystemFramework) const
{
  FileManager &FileMgr = HS.getFileMgr();

  // Framework names must have a '/' in the filename.
  size_t SlashPos = Filename.find('/');
  if (SlashPos == StringRef::npos) return nullptr;

  // Find out if this is the home for the specified framework, by checking
  // HeaderSearch.  Possible answers are yes/no and unknown.
  HeaderSearch::FrameworkCacheEntry &CacheEntry =
    HS.LookupFrameworkCache(Filename.substr(0, SlashPos));

  // If it is known and in some other directory, fail.
  if (CacheEntry.Directory && CacheEntry.Directory != getFrameworkDir())
    return nullptr;

  // Otherwise, construct the path to this framework dir.

  // FrameworkName = "/System/Library/Frameworks/"
  SmallString<1024> FrameworkName;
  FrameworkName += getFrameworkDir()->getName();
  if (FrameworkName.empty() || FrameworkName.back() != '/')
    FrameworkName.push_back('/');

  // FrameworkName = "/System/Library/Frameworks/Cocoa"
  StringRef ModuleName(Filename.begin(), SlashPos);
  FrameworkName += ModuleName;

  // FrameworkName = "/System/Library/Frameworks/Cocoa.framework/"
  FrameworkName += ".framework/";

  // If the cache entry was unresolved, populate it now.
  if (!CacheEntry.Directory) {
    HS.IncrementFrameworkLookupCount();

    // If the framework dir doesn't exist, we fail.
    const DirectoryEntry *Dir = FileMgr.getDirectory(FrameworkName.str());
    if (!Dir) return nullptr;

    // Otherwise, if it does, remember that this is the right direntry for this
    // framework.
    CacheEntry.Directory = getFrameworkDir();

    // If this is a user search directory, check if the framework has been
    // user-specified as a system framework.
    if (getDirCharacteristic() == SrcMgr::C_User) {
      SmallString<1024> SystemFrameworkMarker(FrameworkName);
      SystemFrameworkMarker += ".system_framework";
      if (llvm::sys::fs::exists(SystemFrameworkMarker.str())) {
        CacheEntry.IsUserSpecifiedSystemFramework = true;
      }
    }
  }

  // Set the 'user-specified system framework' flag.
  InUserSpecifiedSystemFramework = CacheEntry.IsUserSpecifiedSystemFramework;

  if (RelativePath) {
    RelativePath->clear();
    RelativePath->append(Filename.begin()+SlashPos+1, Filename.end());
  }

  // Check "/System/Library/Frameworks/Cocoa.framework/Headers/file.h"
  unsigned OrigSize = FrameworkName.size();

  FrameworkName += "Headers/";

  if (SearchPath) {
    SearchPath->clear();
    // Without trailing '/'.
    SearchPath->append(FrameworkName.begin(), FrameworkName.end()-1);
  }

  FrameworkName.append(Filename.begin()+SlashPos+1, Filename.end());
  const FileEntry *FE = FileMgr.getFile(FrameworkName.str(),
                                        /*openFile=*/!SuggestedModule);
  if (!FE) {
    // Check "/System/Library/Frameworks/Cocoa.framework/PrivateHeaders/file.h"
    const char *Private = "Private";
    FrameworkName.insert(FrameworkName.begin()+OrigSize, Private,
                         Private+strlen(Private));
    if (SearchPath)
      SearchPath->insert(SearchPath->begin()+OrigSize, Private,
                         Private+strlen(Private));

    FE = FileMgr.getFile(FrameworkName.str(), /*openFile=*/!SuggestedModule);
  }

  // If we found the header and are allowed to suggest a module, do so now.
  if (FE && SuggestedModule) {
    // Find the framework in which this header occurs.
//.........这里部分代码省略.........

/// LookupFile - Given a "foo" or \<foo> reference, look up the indicated file,
/// return null on failure.  isAngled indicates whether the file reference is
/// for system \#include's or not (i.e. using <> instead of "").  CurFileEnt, if
/// non-null, indicates where the \#including file is, in case a relative search
/// is needed.
const FileEntry *HeaderSearch::LookupFile(
    StringRef Filename,
    bool isAngled,
    const DirectoryLookup *FromDir,
    const DirectoryLookup *&CurDir,
    const FileEntry *CurFileEnt,
    SmallVectorImpl<char> *SearchPath,
    SmallVectorImpl<char> *RelativePath,
    Module **SuggestedModule,
    bool SkipCache)
{
  if (SuggestedModule)
    *SuggestedModule = 0;
    
  // If 'Filename' is absolute, check to see if it exists and no searching.
  if (llvm::sys::path::is_absolute(Filename)) {
    CurDir = 0;

    // If this was an #include_next "/absolute/file", fail.
    if (FromDir) return 0;

    if (SearchPath != NULL)
      SearchPath->clear();
    if (RelativePath != NULL) {
      RelativePath->clear();
      RelativePath->append(Filename.begin(), Filename.end());
    }
    // Otherwise, just return the file.
    return FileMgr.getFile(Filename, /*openFile=*/true);
  }

  // Unless disabled, check to see if the file is in the #includer's
  // directory.  This has to be based on CurFileEnt, not CurDir, because
  // CurFileEnt could be a #include of a subdirectory (#include "foo/bar.h") and
  // a subsequent include of "baz.h" should resolve to "whatever/foo/baz.h".
  // This search is not done for <> headers.
  if (CurFileEnt && !isAngled && !NoCurDirSearch) {
    SmallString<1024> TmpDir;
    // Concatenate the requested file onto the directory.
    // FIXME: Portability.  Filename concatenation should be in sys::Path.
    TmpDir += CurFileEnt->getDir()->getName();
    TmpDir.push_back('/');
    TmpDir.append(Filename.begin(), Filename.end());
    if (const FileEntry *FE = FileMgr.getFile(TmpDir.str(),/*openFile=*/true)) {
      // Leave CurDir unset.
      // This file is a system header or C++ unfriendly if the old file is.
      //
      // Note that the temporary 'DirInfo' is required here, as either call to
      // getFileInfo could resize the vector and we don't want to rely on order
      // of evaluation.
      unsigned DirInfo = getFileInfo(CurFileEnt).DirInfo;
      getFileInfo(FE).DirInfo = DirInfo;
      if (SearchPath != NULL) {
        StringRef SearchPathRef(CurFileEnt->getDir()->getName());
        SearchPath->clear();
        SearchPath->append(SearchPathRef.begin(), SearchPathRef.end());
      }
      if (RelativePath != NULL) {
        RelativePath->clear();
        RelativePath->append(Filename.begin(), Filename.end());
      }
      return FE;
    }
  }

  CurDir = 0;

  // If this is a system #include, ignore the user #include locs.
  unsigned i = isAngled ? AngledDirIdx : 0;

  // If this is a #include_next request, start searching after the directory the
  // file was found in.
  if (FromDir)
    i = FromDir-&SearchDirs[0];

  // Cache all of the lookups performed by this method.  Many headers are
  // multiply included, and the "pragma once" optimization prevents them from
  // being relex/pp'd, but they would still have to search through a
  // (potentially huge) series of SearchDirs to find it.
  std::pair<unsigned, unsigned> &CacheLookup =
    LookupFileCache.GetOrCreateValue(Filename).getValue();

  // If the entry has been previously looked up, the first value will be
  // non-zero.  If the value is equal to i (the start point of our search), then
  // this is a matching hit.
  if (!SkipCache && CacheLookup.first == i+1) {
    // Skip querying potentially lots of directories for this lookup.
    i = CacheLookup.second;
  } else {
    // Otherwise, this is the first query, or the previous query didn't match
    // our search start.  We will fill in our found location below, so prime the
    // start point value.
    CacheLookup.first = i+1;
  }

//.........这里部分代码省略.........

/// DoFrameworkLookup - Do a lookup of the specified file in the current
/// DirectoryLookup, which is a framework directory.
const FileEntry *DirectoryLookup::DoFrameworkLookup(
    StringRef Filename,
    HeaderSearch &HS,
    SmallVectorImpl<char> *SearchPath,
    SmallVectorImpl<char> *RelativePath,
    Module **SuggestedModule,
    bool &InUserSpecifiedSystemFramework) const
{
  FileManager &FileMgr = HS.getFileMgr();

  // Framework names must have a '/' in the filename.
  size_t SlashPos = Filename.find('/');
  if (SlashPos == StringRef::npos) return 0;

  // Find out if this is the home for the specified framework, by checking
  // HeaderSearch.  Possible answers are yes/no and unknown.
  HeaderSearch::FrameworkCacheEntry &CacheEntry =
    HS.LookupFrameworkCache(Filename.substr(0, SlashPos));

  // If it is known and in some other directory, fail.
  if (CacheEntry.Directory && CacheEntry.Directory != getFrameworkDir())
    return 0;

  // Otherwise, construct the path to this framework dir.

  // FrameworkName = "/System/Library/Frameworks/"
  SmallString<1024> FrameworkName;
  FrameworkName += getFrameworkDir()->getName();
  if (FrameworkName.empty() || FrameworkName.back() != '/')
    FrameworkName.push_back('/');

  // FrameworkName = "/System/Library/Frameworks/Cocoa"
  StringRef ModuleName(Filename.begin(), SlashPos);
  FrameworkName += ModuleName;

  // FrameworkName = "/System/Library/Frameworks/Cocoa.framework/"
  FrameworkName += ".framework/";

  // If the cache entry was unresolved, populate it now.
  if (CacheEntry.Directory == 0) {
    HS.IncrementFrameworkLookupCount();

    // If the framework dir doesn't exist, we fail.
    const DirectoryEntry *Dir = FileMgr.getDirectory(FrameworkName.str());
    if (Dir == 0) return 0;

    // Otherwise, if it does, remember that this is the right direntry for this
    // framework.
    CacheEntry.Directory = getFrameworkDir();

    // If this is a user search directory, check if the framework has been
    // user-specified as a system framework.
    if (getDirCharacteristic() == SrcMgr::C_User) {
      SmallString<1024> SystemFrameworkMarker(FrameworkName);
      SystemFrameworkMarker += ".system_framework";
      if (llvm::sys::fs::exists(SystemFrameworkMarker.str())) {
        CacheEntry.IsUserSpecifiedSystemFramework = true;
      }
    }
  }

  // Set the 'user-specified system framework' flag.
  InUserSpecifiedSystemFramework = CacheEntry.IsUserSpecifiedSystemFramework;

  if (RelativePath != NULL) {
    RelativePath->clear();
    RelativePath->append(Filename.begin()+SlashPos+1, Filename.end());
  }

  // If we're allowed to look for modules, try to load or create the module
  // corresponding to this framework.
  Module *Module = 0;
  if (SuggestedModule) {
    if (const DirectoryEntry *FrameworkDir
                                        = FileMgr.getDirectory(FrameworkName)) {
      bool IsSystem = getDirCharacteristic() != SrcMgr::C_User;
      Module = HS.loadFrameworkModule(ModuleName, FrameworkDir, IsSystem);
    }
  }
  
  // Check "/System/Library/Frameworks/Cocoa.framework/Headers/file.h"
  unsigned OrigSize = FrameworkName.size();

  FrameworkName += "Headers/";

  if (SearchPath != NULL) {
    SearchPath->clear();
    // Without trailing '/'.
    SearchPath->append(FrameworkName.begin(), FrameworkName.end()-1);
  }

  // Determine whether this is the module we're building or not.
  bool AutomaticImport = Module;  
  FrameworkName.append(Filename.begin()+SlashPos+1, Filename.end());
  if (const FileEntry *FE = FileMgr.getFile(FrameworkName.str(),
                                            /*openFile=*/!AutomaticImport)) {
    if (AutomaticImport)
      *SuggestedModule = HS.findModuleForHeader(FE);
//.........这里部分代码省略.........

/// LookupFile - Given a "foo" or \<foo> reference, look up the indicated file,
/// return null on failure.  isAngled indicates whether the file reference is
/// for system \#include's or not (i.e. using <> instead of ""). Includers, if
/// non-empty, indicates where the \#including file(s) are, in case a relative
/// search is needed. Microsoft mode will pass all \#including files.
const FileEntry *HeaderSearch::LookupFile(
    StringRef Filename, SourceLocation IncludeLoc, bool isAngled,
    const DirectoryLookup *FromDir, const DirectoryLookup *&CurDir,
    ArrayRef<const FileEntry *> Includers, SmallVectorImpl<char> *SearchPath,
    SmallVectorImpl<char> *RelativePath,
    ModuleMap::KnownHeader *SuggestedModule, bool SkipCache) {
  if (!HSOpts->ModuleMapFiles.empty()) {
    // Preload all explicitly specified module map files. This enables modules
    // map files lying in a directory structure separate from the header files
    // that they describe. These cannot be loaded lazily upon encountering a
    // header file, as there is no other known mapping from a header file to its
    // module map file.
    for (llvm::SetVector<std::string>::iterator
             I = HSOpts->ModuleMapFiles.begin(),
             E = HSOpts->ModuleMapFiles.end();
         I != E; ++I) {
      const FileEntry *File = FileMgr.getFile(*I);
      if (!File)
        continue;
      loadModuleMapFile(File, /*IsSystem=*/false);
    }
    HSOpts->ModuleMapFiles.clear();
  }

  if (SuggestedModule)
    *SuggestedModule = ModuleMap::KnownHeader();
    
  // If 'Filename' is absolute, check to see if it exists and no searching.
  if (llvm::sys::path::is_absolute(Filename)) {
    CurDir = 0;

    // If this was an #include_next "/absolute/file", fail.
    if (FromDir) return 0;

    if (SearchPath != NULL)
      SearchPath->clear();
    if (RelativePath != NULL) {
      RelativePath->clear();
      RelativePath->append(Filename.begin(), Filename.end());
    }
    // Otherwise, just return the file.
    return FileMgr.getFile(Filename, /*openFile=*/true);
  }

  // This is the header that MSVC's header search would have found.
  const FileEntry *MSFE = 0;

  // Unless disabled, check to see if the file is in the #includer's
  // directory.  This cannot be based on CurDir, because each includer could be
  // a #include of a subdirectory (#include "foo/bar.h") and a subsequent
  // include of "baz.h" should resolve to "whatever/foo/baz.h".
  // This search is not done for <> headers.
  if (!Includers.empty() && !isAngled && !NoCurDirSearch) {
    SmallString<1024> TmpDir;
    for (ArrayRef<const FileEntry *>::iterator I = Includers.begin(),
                                               E = Includers.end();
         I != E; ++I) {
      const FileEntry *Includer = *I;
      // Concatenate the requested file onto the directory.
      // FIXME: Portability.  Filename concatenation should be in sys::Path.
      TmpDir = Includer->getDir()->getName();
      TmpDir.push_back('/');
      TmpDir.append(Filename.begin(), Filename.end());
      if (const FileEntry *FE =
              FileMgr.getFile(TmpDir.str(), /*openFile=*/true)) {
        // Leave CurDir unset.
        // This file is a system header or C++ unfriendly if the old file is.
        //
        // Note that we only use one of FromHFI/ToHFI at once, due to potential
        // reallocation of the underlying vector potentially making the first
        // reference binding dangling.
        HeaderFileInfo &FromHFI = getFileInfo(Includer);
        unsigned DirInfo = FromHFI.DirInfo;
        bool IndexHeaderMapHeader = FromHFI.IndexHeaderMapHeader;
        StringRef Framework = FromHFI.Framework;

        HeaderFileInfo &ToHFI = getFileInfo(FE);
        ToHFI.DirInfo = DirInfo;
        ToHFI.IndexHeaderMapHeader = IndexHeaderMapHeader;
        ToHFI.Framework = Framework;

        if (SearchPath != NULL) {
          StringRef SearchPathRef(Includer->getDir()->getName());
          SearchPath->clear();
          SearchPath->append(SearchPathRef.begin(), SearchPathRef.end());
        }
        if (RelativePath != NULL) {
          RelativePath->clear();
          RelativePath->append(Filename.begin(), Filename.end());
        }
        if (I == Includers.begin())
          return FE;

        // Otherwise, we found the path via MSVC header search rules.  If
        // -Wmsvc-include is enabled, we have to keep searching to see if we
//.........这里部分代码省略.........

/// StringifyArgument - Implement C99 6.10.3.2p2, converting a sequence of
/// tokens into the literal string token that should be produced by the C #
/// preprocessor operator.  If Charify is true, then it should be turned into
/// a character literal for the Microsoft charize (#@) extension.
///
Token MacroArgs::StringifyArgument(const Token *ArgToks,
                                   Preprocessor &PP, bool Charify,
                                   SourceLocation ExpansionLocStart,
                                   SourceLocation ExpansionLocEnd) {
  Token Tok;
  Tok.startToken();
  Tok.setKind(Charify ? tok::char_constant : tok::string_literal);

  const Token *ArgTokStart = ArgToks;

  // Stringify all the tokens.
  SmallString<128> Result;
  Result += "\"";

  bool isFirst = true;
  for (; ArgToks->isNot(tok::eof); ++ArgToks) {
    const Token &Tok = *ArgToks;
    if (!isFirst && (Tok.hasLeadingSpace() || Tok.isAtStartOfLine()))
      Result += ' ';
    isFirst = false;

    // If this is a string or character constant, escape the token as specified
    // by 6.10.3.2p2.
    if (tok::isStringLiteral(Tok.getKind()) || // "foo", u8R"x(foo)x"_bar, etc.
        Tok.is(tok::char_constant) ||          // 'x'
        Tok.is(tok::wide_char_constant) ||     // L'x'.
        Tok.is(tok::utf8_char_constant) ||     // u8'x'.
        Tok.is(tok::utf16_char_constant) ||    // u'x'.
        Tok.is(tok::utf32_char_constant)) {    // U'x'.
      bool Invalid = false;
      std::string TokStr = PP.getSpelling(Tok, &Invalid);
      if (!Invalid) {
        std::string Str = Lexer::Stringify(TokStr);
        Result.append(Str.begin(), Str.end());
      }
    } else if (Tok.is(tok::code_completion)) {
      PP.CodeCompleteNaturalLanguage();
    } else {
      // Otherwise, just append the token.  Do some gymnastics to get the token
      // in place and avoid copies where possible.
      unsigned CurStrLen = Result.size();
      Result.resize(CurStrLen+Tok.getLength());
      const char *BufPtr = Result.data() + CurStrLen;
      bool Invalid = false;
      unsigned ActualTokLen = PP.getSpelling(Tok, BufPtr, &Invalid);

      if (!Invalid) {
        // If getSpelling returned a pointer to an already uniqued version of
        // the string instead of filling in BufPtr, memcpy it onto our string.
        if (ActualTokLen && BufPtr != &Result[CurStrLen])
          memcpy(&Result[CurStrLen], BufPtr, ActualTokLen);

        // If the token was dirty, the spelling may be shorter than the token.
        if (ActualTokLen != Tok.getLength())
          Result.resize(CurStrLen+ActualTokLen);
      }
    }
  }

  // If the last character of the string is a \, and if it isn't escaped, this
  // is an invalid string literal, diagnose it as specified in C99.
  if (Result.back() == '\\') {
    // Count the number of consecutive \ characters.  If even, then they are
    // just escaped backslashes, otherwise it's an error.
    unsigned FirstNonSlash = Result.size()-2;
    // Guaranteed to find the starting " if nothing else.
    while (Result[FirstNonSlash] == '\\')
      --FirstNonSlash;
    if ((Result.size()-1-FirstNonSlash) & 1) {
      // Diagnose errors for things like: #define F(X) #X   /   F(\)
      PP.Diag(ArgToks[-1], diag::pp_invalid_string_literal);
      Result.pop_back();  // remove one of the \'s.
    }
  }
  Result += '"';

  // If this is the charify operation and the result is not a legal character
  // constant, diagnose it.
  if (Charify) {
    // First step, turn double quotes into single quotes:
    Result[0] = '\'';
    Result[Result.size()-1] = '\'';

    // Check for bogus character.
    bool isBad = false;
    if (Result.size() == 3)
      isBad = Result[1] == '\'';   // ''' is not legal. '\' already fixed above.
    else
      isBad = (Result.size() != 4 || Result[1] != '\\');  // Not '\x'

    if (isBad) {
      PP.Diag(ArgTokStart[0], diag::err_invalid_character_to_charify);
      Result = "' '";  // Use something arbitrary, but legal.
    }
  }
//.........这里部分代码省略.........

static std::string getImplibPath(StringRef Path) {
  SmallString<128> Out = StringRef("lib");
  Out.append(Path);
  sys::path::replace_extension(Out, ".a");
  return Out.str();
}