Re: Long lines and bidi

[Dmitry Antipov <dmantipov@yandex.ru>]

Yet another interesting profile (generated by scroll-both micro-benchmark with
r111730) is shown below.

Input is 4K lines, each line is ~27K bytes, Imla'ei (modern Arabic) script. IIUC
this R2L text with long lines should push bidi really hard, but ... bidi core
routines (by itself) are almost irrelevant in the profile:

     39.96%        emacs  emacs                          [.] scan_buffer
     28.72%        emacs  emacs                          [.] buf_charpos_to_bytepos
     21.82%        emacs  emacs                          [.] buf_bytepos_to_charpos
      0.59%        emacs  emacs                          [.] re_match_2_internal
      0.51%        emacs  emacs                          [.] sub_char_table_ref
      0.42%        emacs  emacs                          [.] mark_object
      0.23%        emacs  emacs                          [.] composition_gstring_width
      0.19%        emacs  libc-2.16.so                   [.] __memcpy_ssse3_back
      0.18%        emacs  emacs                          [.] x_produce_glyphs
      0.17%        emacs  emacs                          [.] move_it_in_display_line_to
      0.17%        emacs  emacs                          [.] hash_lookup
      0.17%        emacs  emacs                          [.] Fgarbage_collect
      0.17%        emacs  emacs                          [.] lface_hash
      0.16%        emacs  emacs                          [.] decode_coding_utf_8
      0.16%        emacs  emacs                          [.] face_for_font
      0.16%        emacs  emacs                          [.] composition_gstring_p
      0.15%        emacs  emacs                          [.] compile_pattern
      0.15%        emacs  emacs                          [.] get_next_display_element
      0.14%        emacs  emacs                          [.] bidi_level_of_next_char
      0.12%        emacs  emacs                          [.] font_range
      0.12%        emacs  emacs                          [.] bidi_fetch_char
      0.12%        emacs  emacs                          [.] internal_equal
      0.11%        emacs  emacs                          [.] autocmp_chars
      0.11%        emacs  emacs                          [.] char_table_ref
      0.11%        emacs  libgtk-3.so.0.600.4            [.] 0x0000000000115bf0
      0.10%        emacs  emacs                          [.] next_element_from_buffer
      0.10%        emacs  emacs                          [.] composition_update_it
      0.10%        emacs  emacs                          [.] boyer_moore

Dmitry