Commit af6b8d51 authored by peter klausler's avatar peter klausler
Browse files

[flang] Refine CR handling 

We need to retain carriage return characters in source files
that are not parts of multi-byte line endings; they are
significant in CHARACTER literal constants.

Reviewed By: tskeith

Differential Revision: https://reviews.llvm.org/D83808
parent c1e2f73c

flang/include/flang/Parser/char-buffer.h

+0 −3
Original line number Diff line number Diff line
@@ -58,9 +58,6 @@ public: 


  std::string Marshal() const;



  // Removes carriage returns ('\r') and ensures a final line feed ('\n').

  std::string MarshalNormalized() const;



private:

  struct Block {

    static constexpr std::size_t capacity{1 << 20};

flang/lib/Parser/char-buffer.cpp

+0 −22
Original line number Diff line number Diff line
@@ -65,26 +65,4 @@ std::string CharBuffer::Marshal() const { 
  CHECK(result.size() == bytes_);

  return result;

}



std::string CharBuffer::MarshalNormalized() const {

  std::string result;

  std::size_t bytes{bytes_};

  result.reserve(bytes + 1 /* for terminal line feed */);

  char ch{'\0'};

  for (const Block &block : blocks_) {

    std::size_t chunk{std::min(bytes, Block::capacity)};

    for (std::size_t j{0}; j < chunk; ++j) {

      ch = block.data[j];

      if (ch != '\r') {

        result += ch;

      }

    }

    bytes -= chunk;

  }

  if (ch != '\n') {

    result += '\n';

  }

  result.shrink_to_fit();

  return result;

}

} // namespace Fortran::parser

flang/lib/Parser/source.cpp

+11 −2
Original line number Diff line number Diff line
@@ -85,10 +85,19 @@ std::size_t RemoveCarriageReturns(llvm::MutableArrayRef<char> buf) { 
      break;

    }

    std::size_t chunk = crcp - p;

    auto advance{chunk + 1};

    if (chunk + 1 >= bytes || crcp[1] == '\n') {

      // CR followed by LF or EOF: omit

    } else if ((chunk == 0 && p == buf.data()) || crcp[-1] == '\n') {

      // CR preceded by LF or BOF: omit

    } else {

      // CR in line: retain

      ++chunk;

    }

    std::memmove(buffer + wrote, p, chunk);

    wrote += chunk;

    p += chunk + 1;

    bytes -= chunk + 1;

    p += advance;

    bytes -= advance;

  }

  return wrote;

}