C++ StringRef::find方法代码示例

std::string getClangRepositoryPath() {
#ifdef SVN_REPOSITORY
  llvm::StringRef URL(SVN_REPOSITORY);
#else
  llvm::StringRef URL("");
#endif

  // If the SVN_REPOSITORY is empty, try to use the SVN keyword. This helps us
  // pick up a tag in an SVN export, for example.
  static llvm::StringRef SVNRepository("$URL$");
  if (URL.empty()) {
    URL = SVNRepository.slice(SVNRepository.find(':'),
                              SVNRepository.find("/lib/Basic"));
  }

  // Strip off version from a build from an integration branch.
  URL = URL.slice(0, URL.find("/src/tools/clang"));

  // Trim path prefix off, assuming path came from standard cfe path.
  size_t Start = URL.find("cfe/");
  if (Start != llvm::StringRef::npos)
    URL = URL.substr(Start + 4);

  return URL;
}

PythonObject PythonObject::ResolveName(llvm::StringRef name) const {
  // Resolve the name in the context of the specified object.  If, for example,
  // `this` refers to a PyModule, then this will look for `name` in this
  // module.  If `this` refers to a PyType, then it will resolve `name` as an
  // attribute of that type.  If `this` refers to an instance of an object,
  // then it will resolve `name` as the value of the specified field.
  //
  // This function handles dotted names so that, for example, if `m_py_obj`
  // refers to the `sys` module, and `name` == "path.append", then it will find
  // the function `sys.path.append`.

  size_t dot_pos = name.find('.');
  if (dot_pos == llvm::StringRef::npos) {
    // No dots in the name, we should be able to find the value immediately as
    // an attribute of `m_py_obj`.
    return GetAttributeValue(name);
  }

  // Look up the first piece of the name, and resolve the rest as a child of
  // that.
  PythonObject parent = ResolveName(name.substr(0, dot_pos));
  if (!parent.IsAllocated())
    return PythonObject();

  // Tail recursion.. should be optimized by the compiler
  return parent.ResolveName(name.substr(dot_pos + 1));
}

/// HandleComment - Hook into the preprocessor and extract comments containing
///  expected errors and warnings.
bool VerifyDiagnosticConsumer::HandleComment(Lexer &PP, const SourceLocation& CommentBegin, const llvm::StringRef &C) {
  const llvm::SourceMgr &SM = PP.getSourceManager();

  // If this comment is for a different source manager, ignore it.
  if (SrcManager && &SM != SrcManager)
    return false;

  if (C.empty())
    return false;

  // Fold any "\<EOL>" sequences
  size_t loc = C.find('\\');
  if (loc == StringRef::npos) {
    ParseDirective(C, &ED, SM, &PP, CommentBegin, Status);
    return false;
  }

  std::string C2;
  C2.reserve(C.size());

  for (size_t last = 0;; loc = C.find('\\', last)) {
    if (loc == StringRef::npos || loc == C.size()) {
      C2 += C.substr(last);
      break;
    }
    C2 += C.substr(last, loc-last);
    last = loc + 1;

    if (C[last] == '\n' || C[last] == '\r') {
      ++last;

      // Escape \r\n  or \n\r, but not \n\n.
      if (last < C.size())
        if (C[last] == '\n' || C[last] == '\r')
          if (C[last] != C[last-1])
            ++last;
    } else {
      // This was just a normal backslash.
      C2 += '\\';
    }
  }

  if (!C2.empty())
    ParseDirective(C2, &ED, SM, &PP, CommentBegin, Status);
  return false;
}

// Return the index to RSA if found; otherwise -1 is returned.
static int32_t
WithRSAIndex(llvm::StringRef &Arg)
{
    
    uint32_t i;
    for (i = 0; i < 4; ++i)
        if (Arg.find(RSA[i]) != llvm::StringRef::npos)
            return i;
    return -1;
}

bool GetSystemLibraryPaths(llvm::SmallVectorImpl<std::string>& Paths) {
#if defined(__APPLE__) || defined(__CYGWIN__)
  Paths.push_back("/usr/local/lib/");
  Paths.push_back("/usr/X11R6/lib/");
  Paths.push_back("/usr/lib/");
  Paths.push_back("/lib/");

 #ifndef __APPLE__
  Paths.push_back("/lib/x86_64-linux-gnu/");
  Paths.push_back("/usr/local/lib64/");
  Paths.push_back("/usr/lib64/");
  Paths.push_back("/lib64/");
 #endif
#else
  llvm::SmallString<1024> Buf;
  platform::Popen("LD_DEBUG=libs LD_PRELOAD=DOESNOTEXIST ls", Buf, true);
  const llvm::StringRef Result = Buf.str();

  const std::size_t NPos = std::string::npos;
  const std::size_t LD = Result.find("(LD_LIBRARY_PATH)");
  std::size_t From = Result.find("search path=", LD == NPos ? 0 : LD);
  if (From != NPos) {
    const std::size_t To = Result.find("(system search path)", From);
    if (To != NPos) {
      From += 12;
      std::string SysPath = Result.substr(From, To-From);
      SysPath.erase(std::remove_if(SysPath.begin(), SysPath.end(), isspace),
                    SysPath.end());

      llvm::SmallVector<llvm::StringRef, 10> CurPaths;
      SplitPaths(SysPath, CurPaths);
      for (const auto& Path : CurPaths)
        Paths.push_back(Path.str());
    }
  }
#endif
  return true;
}

PythonObject
PythonObject::ResolveNameWithDictionary(llvm::StringRef name,
                                        const PythonDictionary &dict) {
  size_t dot_pos = name.find('.');
  llvm::StringRef piece = name.substr(0, dot_pos);
  PythonObject result = dict.GetItemForKey(PythonString(piece));
  if (dot_pos == llvm::StringRef::npos) {
    // There was no dot, we're done.
    return result;
  }

  // There was a dot.  The remaining portion of the name should be looked up in
  // the context of the object that was found in the dictionary.
  return result.ResolveName(name.substr(dot_pos + 1));
}

static bool opstring(llvm::SmallString<16> &x) {
    const char *p = save();
    const char *q = p;
    char y;
    while (next(y)) {
        if (opchars.find(y) != llvm::StringRef::npos)
            q = save();
        else
            break;
    }
    restore(q);
    if (p == q) return false;
    x = llvm::StringRef(p,q-p);
    return true;
}

void InitHeaderSearch::AddDelimitedPaths(llvm::StringRef at) {
  if (at.empty()) // Empty string should not add '.' path.
    return;

  llvm::StringRef::size_type delim;
  while ((delim = at.find(llvm::sys::PathSeparator)) != llvm::StringRef::npos) {
    if (delim == 0)
      AddPath(".", Angled, false, true, false);
    else
      AddPath(at.substr(0, delim), Angled, false, true, false);
    at = at.substr(delim + 1);
  }

  if (at.empty())
    AddPath(".", Angled, false, true, false);
  else
    AddPath(at, Angled, false, true, false);
}

bool IncrementalExecutor::diagnoseUnresolvedSymbols(llvm::StringRef trigger,
                                                    llvm::StringRef title) {
  if (m_unresolvedSymbols.empty())
    return false;

  llvm::SmallVector<llvm::Function*, 128> funcsToFree;
  for (std::set<std::string>::const_iterator i = m_unresolvedSymbols.begin(),
         e = m_unresolvedSymbols.end(); i != e; ++i) {
#if 0
    // FIXME: This causes a lot of test failures, for some reason it causes
    // the call to HandleMissingFunction to be elided.
    unsigned diagID = m_Diags.getCustomDiagID(clang::DiagnosticsEngine::Error,
                                              "%0 unresolved while jitting %1");
    (void)diagID;
    //m_Diags.Report(diagID) << *i << funcname; // TODO: demangle the names.
#endif

    llvm::errs() << "IncrementalExecutor::executeFunction: symbol '" << *i
                 << "' unresolved while linking ";
    if (trigger.find(utils::Synthesize::UniquePrefix) != llvm::StringRef::npos)
      llvm::errs() << "[cling interface function]";
    else {
      if (!title.empty())
        llvm::errs() << title << " '";
      llvm::errs() << trigger;
      if (!title.empty())
        llvm::errs() << "'";
    }
    llvm::errs() << "!\n";

    // Be helpful, demangle!
    std::string demangledName;
    {
#ifndef LLVM_ON_WIN32
      int status = 0;
      char *demang = abi::__cxa_demangle(i->c_str(), 0, 0, &status);
      if (status == 0)
        demangledName = demang;
      free(demang);
#else
      if (char* demang = __unDName(0, i->c_str(), 0, malloc, free, 0)) {
        demangledName = demang;
        free(demang);
      }
#endif
    }
    if (!demangledName.empty()) {
       llvm::errs()
          << "You are probably missing the definition of "
          << demangledName << "\n"
          << "Maybe you need to load the corresponding shared library?\n";
    }

    //llvm::Function *ff = m_engine->FindFunctionNamed(i->c_str());
    // i could also reference a global variable, in which case ff == 0.
    //if (ff)
    //  funcsToFree.push_back(ff);
  }
  //freeCallersOfUnresolvedSymbols(funcsToFree, m_engine.get());
  m_unresolvedSymbols.clear();
  return true;
}

bool needsQuotes(const llvm::StringRef &arg) {
  return // not already quoted
      !(arg.size() > 1 && arg[0] == '"' &&
        arg.back() == '"') && // empty or min 1 space or min 1 double quote
      (arg.empty() || arg.find(' ') != arg.npos || arg.find('"') != arg.npos);
}

void InefficientAlgorithmCheck::check(const MatchFinder::MatchResult &Result) {
  const auto *AlgCall = Result.Nodes.getNodeAs<CallExpr>("IneffAlg");
  const auto *IneffCont =
      Result.Nodes.getNodeAs<ClassTemplateSpecializationDecl>("IneffCont");
  bool PtrToContainer = false;
  if (!IneffCont) {
    IneffCont =
        Result.Nodes.getNodeAs<ClassTemplateSpecializationDecl>("IneffContPtr");
    PtrToContainer = true;
  }
  const llvm::StringRef IneffContName = IneffCont->getName();
  const bool Unordered =
      IneffContName.find("unordered") != llvm::StringRef::npos;
  const bool Maplike = IneffContName.find("map") != llvm::StringRef::npos;

  // Store if the key type of the container is compatible with the value
  // that is searched for.
  QualType ValueType = AlgCall->getArg(2)->getType();
  QualType KeyType =
      IneffCont->getTemplateArgs()[0].getAsType().getCanonicalType();
  const bool CompatibleTypes = areTypesCompatible(KeyType, ValueType);

  // Check if the comparison type for the algorithm and the container matches.
  if (AlgCall->getNumArgs() == 4 && !Unordered) {
    const Expr *Arg = AlgCall->getArg(3);
    const QualType AlgCmp =
        Arg->getType().getUnqualifiedType().getCanonicalType();
    const unsigned CmpPosition =
        (IneffContName.find("map") == llvm::StringRef::npos) ? 1 : 2;
    const QualType ContainerCmp = IneffCont->getTemplateArgs()[CmpPosition]
                                      .getAsType()
                                      .getUnqualifiedType()
                                      .getCanonicalType();
    if (AlgCmp != ContainerCmp) {
      diag(Arg->getLocStart(),
           "different comparers used in the algorithm and the container");
      return;
    }
  }

  const auto *AlgDecl = AlgCall->getDirectCallee();
  if (!AlgDecl)
    return;

  if (Unordered && AlgDecl->getName().find("bound") != llvm::StringRef::npos)
    return;

  const auto *AlgParam = Result.Nodes.getNodeAs<Expr>("AlgParam");
  const auto *IneffContExpr = Result.Nodes.getNodeAs<Expr>("IneffContExpr");
  FixItHint Hint;

  SourceManager &SM = *Result.SourceManager;
  LangOptions LangOpts = Result.Context->getLangOpts();

  CharSourceRange CallRange =
      CharSourceRange::getTokenRange(AlgCall->getSourceRange());

  // FIXME: Create a common utility to extract a file range that the given token
  // sequence is exactly spelled at (without macro argument expansions etc.).
  // We can't use Lexer::makeFileCharRange here, because for
  //
  //   #define F(x) x
  //   x(a b c);
  //
  // it will return "x(a b c)", when given the range "a"-"c". It makes sense for
  // removals, but not for replacements.
  //
  // This code is over-simplified, but works for many real cases.
  if (SM.isMacroArgExpansion(CallRange.getBegin()) &&
      SM.isMacroArgExpansion(CallRange.getEnd())) {
    CallRange.setBegin(SM.getSpellingLoc(CallRange.getBegin()));
    CallRange.setEnd(SM.getSpellingLoc(CallRange.getEnd()));
  }

  if (!CallRange.getBegin().isMacroID() && !Maplike && CompatibleTypes) {
    StringRef ContainerText = Lexer::getSourceText(
        CharSourceRange::getTokenRange(IneffContExpr->getSourceRange()), SM,
        LangOpts);
    StringRef ParamText = Lexer::getSourceText(
        CharSourceRange::getTokenRange(AlgParam->getSourceRange()), SM,
        LangOpts);
    std::string ReplacementText =
        (llvm::Twine(ContainerText) + (PtrToContainer ? "->" : ".") +
         AlgDecl->getName() + "(" + ParamText + ")")
            .str();
    Hint = FixItHint::CreateReplacement(CallRange, ReplacementText);
  }

  diag(AlgCall->getLocStart(),
       "this STL algorithm call should be replaced with a container method")
      << Hint;
}