C++ StringRef::rtrim方法代码示例

// Convert a path into the canonical form.
// Canonical form is either "/", or "/segment" * N:
//   C:\foo\bar --> /c:/foo/bar
//   /foo/      --> /foo
//   a/b/c      --> /a/b/c
static SmallString<128> canonicalize(StringRef Path) {
  SmallString<128> Result = Path.rtrim('/');
  native(Result, sys::path::Style::posix);
  if (Result.empty() || Result.front() != '/')
    Result.insert(Result.begin(), '/');
  return Result;
}

static void ParseProgName(SmallVectorImpl<const char *> &ArgVector,
                          std::set<std::string> &SavedStrings) {
  // Try to infer frontend type and default target from the program name by
  // comparing it against DriverSuffixes in order.

  // If there is a match, the function tries to identify a target as prefix.
  // E.g. "x86_64-linux-clang" as interpreted as suffix "clang" with target
  // prefix "x86_64-linux". If such a target prefix is found, is gets added via
  // -target as implicit first argument.

  std::string ProgName =llvm::sys::path::stem(ArgVector[0]);
#ifdef LLVM_ON_WIN32
  // Transform to lowercase for case insensitive file systems.
  ProgName = StringRef(ProgName).lower();
#endif

  StringRef ProgNameRef = ProgName;
  const DriverSuffix *DS = FindDriverSuffix(ProgNameRef);

  if (!DS) {
    // Try again after stripping any trailing version number:
    // clang++3.5 -> clang++
    ProgNameRef = ProgNameRef.rtrim("0123456789.");
    DS = FindDriverSuffix(ProgNameRef);
  }

  if (!DS) {
    // Try again after stripping trailing -component.
    // clang++-tot -> clang++
    ProgNameRef = ProgNameRef.slice(0, ProgNameRef.rfind('-'));
    DS = FindDriverSuffix(ProgNameRef);
  }

  if (DS) {
    if (const char *Flag = DS->ModeFlag) {
      // Add Flag to the arguments.
      auto it = ArgVector.begin();
      if (it != ArgVector.end())
        ++it;
      ArgVector.insert(it, Flag);
    }

    StringRef::size_type LastComponent = ProgNameRef.rfind(
        '-', ProgNameRef.size() - strlen(DS->Suffix));
    if (LastComponent == StringRef::npos)
      return;

    // Infer target from the prefix.
    StringRef Prefix = ProgNameRef.slice(0, LastComponent);
    std::string IgnoredError;
    if (llvm::TargetRegistry::lookupTarget(Prefix, IgnoredError)) {
      auto it = ArgVector.begin();
      if (it != ArgVector.end())
        ++it;
      const char *arr[] = { "-target", GetStableCStr(SavedStrings, Prefix) };
      ArgVector.insert(it, std::begin(arr), std::end(arr));
    }
  }
}

NameStyle::NameStyle(StringRef name)
    : leadingUnderscores(0), trailingUnderscores(0) {
  // Trim leading and trailing underscores.
  StringRef center = name.ltrim("_");
  if (center == "")
    return;
  leadingUnderscores = name.size() - center.size();
  center = center.rtrim("_");
  assert(!center.empty());
  trailingUnderscores = name.size() - center.size() - leadingUnderscores;

  unsigned pos = 0;

  enum Case {
    None = 0,
    Lower,
    Upper,
  };

  auto caseOf = [](char c) {
    if (clang::isLowercase(c))
      return Lower;
    if (clang::isUppercase(c))
      return Upper;
    return None;
  };

  unsigned underscores = 0;
  unsigned caseCount[3] = {0, 0, 0};
  Case leadingCase = None;
  for (; pos < center.size(); ++pos) {
    char c = center[pos];
    Case curCase = caseOf(c);
    if (!leadingCase)
      leadingCase = curCase;

    underscores += (c == '_');
    caseCount[curCase] += 1;
  }

  assert(caseCount[leadingCase] > 0);

  if (caseCount[Lower] && !caseCount[Upper]) {
    wordDelimiter = underscores ? LowercaseWithUnderscores : Lowercase;
    return;
  }
  if (caseCount[Upper] && !caseCount[Lower]) {
    wordDelimiter = underscores ? UppercaseWithUnderscores : Uppercase;
    return;
  }
  if (leadingCase && !underscores) {
    wordDelimiter = leadingCase == Lower ? LowerCamelCase : UpperCamelCase;
    return;
  }

  // FIXME: should we try to choose a delimiter if there is more than one?
  wordDelimiter = Unknown;
}

void llvm::printCOFFSymbolTable(const COFFObjectFile *coff) {
  for (unsigned SI = 0, SE = coff->getNumberOfSymbols(); SI != SE; ++SI) {
    ErrorOr<COFFSymbolRef> Symbol = coff->getSymbol(SI);
    StringRef Name;
    error(Symbol.getError());
    error(coff->getSymbolName(*Symbol, Name));

    outs() << "[" << format("%2d", SI) << "]"
           << "(sec " << format("%2d", int(Symbol->getSectionNumber())) << ")"
           << "(fl 0x00)" // Flag bits, which COFF doesn't have.
           << "(ty " << format("%3x", unsigned(Symbol->getType())) << ")"
           << "(scl " << format("%3x", unsigned(Symbol->getStorageClass())) << ") "
           << "(nx " << unsigned(Symbol->getNumberOfAuxSymbols()) << ") "
           << "0x" << format("%08x", unsigned(Symbol->getValue())) << " "
           << Name << "\n";

    for (unsigned AI = 0, AE = Symbol->getNumberOfAuxSymbols(); AI < AE; ++AI, ++SI) {
      if (Symbol->isSectionDefinition()) {
        const coff_aux_section_definition *asd;
        error(coff->getAuxSymbol<coff_aux_section_definition>(SI + 1, asd));

        int32_t AuxNumber = asd->getNumber(Symbol->isBigObj());

        outs() << "AUX "
               << format("scnlen 0x%x nreloc %d nlnno %d checksum 0x%x "
                         , unsigned(asd->Length)
                         , unsigned(asd->NumberOfRelocations)
                         , unsigned(asd->NumberOfLinenumbers)
                         , unsigned(asd->CheckSum))
               << format("assoc %d comdat %d\n"
                         , unsigned(AuxNumber)
                         , unsigned(asd->Selection));
      } else if (Symbol->isFileRecord()) {
        const char *FileName;
        error(coff->getAuxSymbol<char>(SI + 1, FileName));

        StringRef Name(FileName, Symbol->getNumberOfAuxSymbols() *
                                     coff->getSymbolTableEntrySize());
        outs() << "AUX " << Name.rtrim(StringRef("\0", 1))  << '\n';

        SI = SI + Symbol->getNumberOfAuxSymbols();
        break;
      } else if (Symbol->isWeakExternal()) {
        const coff_aux_weak_external *awe;
        error(coff->getAuxSymbol<coff_aux_weak_external>(SI + 1, awe));

        outs() << "AUX " << format("indx %d srch %d\n",
                                   static_cast<uint32_t>(awe->TagIndex),
                                   static_cast<uint32_t>(awe->Characteristics));
      } else {
        outs() << "AUX Unknown\n";
      }
    }
  }
}

ErrorOr<StringRef> Archive::Child::getName() const {
  StringRef name = getRawName();
  // Check if it's a special name.
  if (name[0] == '/') {
    if (name.size() == 1) // Linker member.
      return name;
    if (name.size() == 2 && name[1] == '/') // String table.
      return name;
    // It's a long name.
    // Get the offset.
    std::size_t offset;
    if (name.substr(1).rtrim(' ').getAsInteger(10, offset))
      llvm_unreachable("Long name offset is not an integer");

    // Verify it.
    if (offset >= Parent->StringTable.size())
      return object_error::parse_failed;
    const char *addr = Parent->StringTable.begin() + offset;

    // GNU long file names end with a "/\n".
    if (Parent->kind() == K_GNU || Parent->kind() == K_MIPS64) {
      StringRef::size_type End = StringRef(addr).find('\n');
      return StringRef(addr, End - 1);
    }
    return StringRef(addr);
  } else if (name.startswith("#1/")) {
    uint64_t name_size;
    if (name.substr(3).rtrim(' ').getAsInteger(10, name_size))
      llvm_unreachable("Long name length is not an ingeter");
    return Data.substr(Header.getSizeOf(), name_size).rtrim('\0');
  } else {
    // It is not a long name so trim the blanks at the end of the name.
    if (name[name.size() - 1] != '/') {
      return name.rtrim(' ');
    }
  }
  // It's a simple name.
  if (name[name.size() - 1] == '/')
    return name.substr(0, name.size() - 1);
  return name;
}

Optional<llvm::markup::ParamField *> extractParamOutlineItem(
    llvm::markup::MarkupContext &MC,
    llvm::markup::MarkupASTNode *Node) {

  auto Item = dyn_cast<llvm::markup::Item>(Node);
  if (!Item)
    return None;

  auto Children = Item->getChildren();
  if (Children.empty())
    return None;

  auto FirstChild = Children.front();
  auto FirstParagraph = dyn_cast<llvm::markup::Paragraph>(FirstChild);
  if (!FirstParagraph)
    return None;

  auto FirstParagraphChildren = FirstParagraph->getChildren();
  if (FirstParagraphChildren.empty())
    return None;

  auto ParagraphText =
      dyn_cast<llvm::markup::Text>(FirstParagraphChildren.front());
  if (!ParagraphText)
    return None;

  StringRef Name;
  StringRef Remainder;
  std::tie(Name, Remainder) = ParagraphText->getLiteralContent().split(':');
  Name = Name.rtrim();

  if (Name.empty())
    return None;

  ParagraphText->setLiteralContent(Remainder.ltrim());

  return llvm::markup::ParamField::create(MC, Name, Children);
}

BreakableToken::Split
BreakableComment::getReflowSplit(StringRef Text, StringRef ReflowPrefix,
                                 unsigned PreviousEndColumn,
                                 unsigned ColumnLimit) const {
  unsigned ReflowStartColumn = PreviousEndColumn + ReflowPrefix.size();
  StringRef TrimmedText = Text.rtrim(Blanks);
  // This is the width of the resulting line in case the full line of Text gets
  // reflown up starting at ReflowStartColumn.
  unsigned FullWidth = ReflowStartColumn + encoding::columnWidthWithTabs(
                                               TrimmedText, ReflowStartColumn,
                                               Style.TabWidth, Encoding);
  // If the full line fits up, we return a reflow split after it,
  // otherwise we compute the largest piece of text that fits after
  // ReflowStartColumn.
  Split ReflowSplit =
      FullWidth <= ColumnLimit
          ? Split(TrimmedText.size(), Text.size() - TrimmedText.size())
          : getCommentSplit(Text, ReflowStartColumn, ColumnLimit,
                            Style.TabWidth, Encoding);

  // We need to be extra careful here, because while it's OK to keep a long line
  // if it can't be broken into smaller pieces (like when the first word of a
  // long line is longer than the column limit), it's not OK to reflow that long
  // word up. So we recompute the size of the previous line after reflowing and
  // only return the reflow split if that's under the line limit.
  if (ReflowSplit.first != StringRef::npos &&
      // Check if the width of the newly reflown line is under the limit.
      PreviousEndColumn + ReflowPrefix.size() +
              encoding::columnWidthWithTabs(Text.substr(0, ReflowSplit.first),
                                            PreviousEndColumn +
                                                ReflowPrefix.size(),
                                            Style.TabWidth, Encoding) <=
          ColumnLimit) {
    return ReflowSplit;
  }
  return Split(StringRef::npos, 0);
}

/// emitBuiltinCall - Emit a call to a builtin function.
void irgen::emitBuiltinCall(IRGenFunction &IGF, Identifier FnId,
                            SILType resultType,
                            Explosion &args, Explosion &out,
                            SubstitutionList substitutions) {
  // Decompose the function's name into a builtin name and type list.
  const BuiltinInfo &Builtin = IGF.getSILModule().getBuiltinInfo(FnId);

  if (Builtin.ID == BuiltinValueKind::UnsafeGuaranteedEnd) {
    // Just consume the incoming argument.
    assert(args.size() == 1 && "Expecting one incoming argument");
    (void)args.claimAll();
    return;
  }

  if (Builtin.ID == BuiltinValueKind::UnsafeGuaranteed) {
    // Just forward the incoming argument.
    assert(args.size() == 1 && "Expecting one incoming argument");
    out = std::move(args);
    // This is a token.
    out.add(llvm::ConstantInt::get(IGF.IGM.Int8Ty, 0));
    return;
  }

  if (Builtin.ID == BuiltinValueKind::OnFastPath) {
    // The onFastPath builtin has only an effect on SIL level, so we lower it
    // to a no-op.
    return;
  }

  // These builtins don't care about their argument:
  if (Builtin.ID == BuiltinValueKind::Sizeof) {
    (void)args.claimAll();
    auto valueTy = getLoweredTypeAndTypeInfo(IGF.IGM,
                                             substitutions[0].getReplacement());
    out.add(valueTy.second.getSize(IGF, valueTy.first));
    return;
  }

  if (Builtin.ID == BuiltinValueKind::Strideof) {
    (void)args.claimAll();
    auto valueTy = getLoweredTypeAndTypeInfo(IGF.IGM,
                                             substitutions[0].getReplacement());
    out.add(valueTy.second.getStride(IGF, valueTy.first));
    return;
  }

  if (Builtin.ID == BuiltinValueKind::Alignof) {
    (void)args.claimAll();
    auto valueTy = getLoweredTypeAndTypeInfo(IGF.IGM,
                                             substitutions[0].getReplacement());
    // The alignof value is one greater than the alignment mask.
    out.add(IGF.Builder.CreateAdd(
                           valueTy.second.getAlignmentMask(IGF, valueTy.first),
                           IGF.IGM.getSize(Size(1))));
    return;
  }

  if (Builtin.ID == BuiltinValueKind::IsPOD) {
    (void)args.claimAll();
    auto valueTy = getLoweredTypeAndTypeInfo(IGF.IGM,
                                             substitutions[0].getReplacement());
    out.add(valueTy.second.getIsPOD(IGF, valueTy.first));
    return;
  }


  // addressof expects an lvalue argument.
  if (Builtin.ID == BuiltinValueKind::AddressOf) {
    llvm::Value *address = args.claimNext();
    llvm::Value *value = IGF.Builder.CreateBitCast(address,
                                                   IGF.IGM.Int8PtrTy);
    out.add(value);
    return;
  }

  // Everything else cares about the (rvalue) argument.

  // If this is an LLVM IR intrinsic, lower it to an intrinsic call.
  const IntrinsicInfo &IInfo = IGF.getSILModule().getIntrinsicInfo(FnId);
  llvm::Intrinsic::ID IID = IInfo.ID;

  // Calls to the int_instrprof_increment intrinsic are emitted during SILGen.
  // At that stage, the function name GV used by the profiling pass is hidden.
  // Fix the intrinsic call here by pointing it to the correct GV.
  if (IID == llvm::Intrinsic::instrprof_increment) {
    // Extract the PGO function name.
    auto *NameGEP = cast<llvm::User>(args.claimNext());
    auto *NameGV = dyn_cast<llvm::GlobalVariable>(NameGEP->stripPointerCasts());
    if (NameGV) {
      auto *NameC = NameGV->getInitializer();
      StringRef Name = cast<llvm::ConstantDataArray>(NameC)->getRawDataValues();
      StringRef PGOFuncName = Name.rtrim(StringRef("\0", 1));

      // Point the increment call to the right function name variable.
      std::string PGOFuncNameVar = llvm::getPGOFuncNameVarName(
          PGOFuncName, llvm::GlobalValue::LinkOnceAnyLinkage);
      auto *FuncNamePtr = IGF.IGM.Module.getNamedGlobal(PGOFuncNameVar);

      if (FuncNamePtr) {
//.........这里部分代码省略.........

LineList MarkupContext::getLineList(swift::RawComment RC) {
  LineListBuilder Builder(*this);

  for (const auto &C : RC.Comments) {
    if (C.isLine()) {
      // Skip comment marker.
      unsigned CommentMarkerBytes = 2 + (C.isOrdinary() ? 0 : 1);
      StringRef Cleaned = C.RawText.drop_front(CommentMarkerBytes);

      // Drop trailing newline.
      Cleaned = Cleaned.rtrim("\n\r");
      auto CleanedStartLoc =
          C.Range.getStart().getAdvancedLocOrInvalid(CommentMarkerBytes);
      auto CleanedEndLoc =
          C.Range.getStart().getAdvancedLocOrInvalid(Cleaned.size());
      Builder.addLine(Cleaned, { CleanedStartLoc, CleanedEndLoc });
    } else {
      // Skip comment markers at the beginning and at the end.
      unsigned CommentMarkerBytes = 2 + (C.isOrdinary() ? 0 : 1);
      StringRef Cleaned = C.RawText.drop_front(CommentMarkerBytes);

      if (Cleaned.endswith("*/"))
        Cleaned = Cleaned.drop_back(2);
      else if (Cleaned.endswith("/"))
        Cleaned = Cleaned.drop_back(1);

      swift::SourceLoc CleanedStartLoc =
          C.Range.getStart().getAdvancedLocOrInvalid(CommentMarkerBytes);

      // Determine if we have leading decorations in this block comment.
      bool HasASCIIArt = false;
      if (swift::startsWithNewline(Cleaned)) {
        Builder.addLine(Cleaned.substr(0, 0), { C.Range.getStart(),
                                                C.Range.getStart() });
        unsigned NewlineBytes = swift::measureNewline(Cleaned);
        Cleaned = Cleaned.drop_front(NewlineBytes);
        CleanedStartLoc = CleanedStartLoc.getAdvancedLocOrInvalid(NewlineBytes);
        HasASCIIArt = measureASCIIArt(Cleaned, C.StartColumn - 1) != 0;
      }

      while (!Cleaned.empty()) {
        size_t Pos = Cleaned.find_first_of("\n\r");
        if (Pos == StringRef::npos)
          Pos = Cleaned.size();

        // Skip over ASCII art, if present.
        if (HasASCIIArt)
          if (unsigned ASCIIArtBytes =
              measureASCIIArt(Cleaned, C.StartColumn - 1)) {
            Cleaned = Cleaned.drop_front(ASCIIArtBytes);
            CleanedStartLoc =
            CleanedStartLoc.getAdvancedLocOrInvalid(ASCIIArtBytes);
            Pos -= ASCIIArtBytes;
          }

        StringRef Line = Cleaned.substr(0, Pos);
        auto CleanedEndLoc = CleanedStartLoc.getAdvancedLocOrInvalid(Pos);

        Cleaned = Cleaned.drop_front(Pos);
        unsigned NewlineBytes = swift::measureNewline(Cleaned);
        Cleaned = Cleaned.drop_front(NewlineBytes);
        Pos += NewlineBytes;
        CleanedStartLoc = CleanedStartLoc.getAdvancedLocOrInvalid(Pos);

        Builder.addLine(Line, { CleanedStartLoc, CleanedEndLoc });
      }
    }
  }
  return Builder.takeLineList();
}