bug#15555: Re: bug#15555: 24.3; Bidirectional display very slow with long lines

[Eli Zaretskii <eliz@gnu.org>]

> Date: Tue, 18 Feb 2014 21:34:46 +0400
> From: Dmitry Antipov <dmantipov@yandex.ru>
> CC: 15555@debbugs.gnu.org
> 
> On 02/18/2014 08:24 PM, Eli Zaretskii wrote:
> 
> > If you show me where these calls are made, I might be able to say
> > something intelligent about that.  And maybe we could even discuss the
> > issue and find some clever solution, if it exists.
> 
> (gdb) b bidi.c:669 ;;; at xmalloc
> Breakpoint 1 at 0x500890: file ../../trunk/src/bidi.c, line 669.
> (gdb) b bidi.c:756 ;;; at xfree
> Breakpoint 2 at 0x500b55: file ../../trunk/src/bidi.c, line 756.
> (gdb) r -Q /tmp/4000.txt
> 
> In 4000.txt, eval (goto-char 2769), then press up arrow ==>
> 
> Breakpoint 1, bidi_shelve_cache () at ../../trunk/src/bidi.c:669
> 669	  databuf = xmalloc (alloc);
> (gdb) p alloc
> $1 = 292820 ;;; ~290K
> (gdb) bt 8
> #0  bidi_shelve_cache () at ../../trunk/src/bidi.c:669
> #1  0x00000000004518d2 in move_it_in_display_line_to (it=0x7fffffff9b60, to_charpos=2769, to_x=0, op=(MOVE_TO_X | MOVE_TO_POS))
>      at ../../trunk/src/xdisp.c:8339
> #2  0x00000000004542d7 in move_it_to (it=0x7fffffff9b60, to_charpos=2769, to_x=-1, to_y=593, to_vpos=-1, op=10)
>      at ../../trunk/src/xdisp.c:8941
> #3  0x000000000043a193 in pos_visible_p (w=0x10e6518, charpos=2769, x=0x7fffffffa93c, y=0x7fffffffa938, rtop=0x7fffffffa94c,
>      rbot=0x7fffffffa948, rowh=0x7fffffffa944, vpos=0x7fffffffa940) at ../../trunk/src/xdisp.c:1409
> #4  0x00000000004aba8c in Fpos_visible_in_window_p (pos=..., window=..., partially=...) at ../../trunk/src/window.c:1812
> #5  0x000000000057f82b in Fposn_at_point (pos=..., window=...) at ../../trunk/src/keyboard.c:10730
> #6  0x000000000060cf02 in Ffuncall (nargs=1, args=0x7fffffffab10) at ../../trunk/src/eval.c:2818
> #7  0x000000000065681f in exec_byte_code (bytestr=..., vector=..., maxdepth=..., args_template=..., nargs=2, args=0x7fffffffb3b0)
>      at ../../trunk/src/bytecode.c:919
> (More stack frames follow...)
> (gdb) c
> Continuing.
> 
> Breakpoint 4, bidi_unshelve_cache (databuf=0x7fffe1a16010, just_free=true) at ../../trunk/src/bidi.c:756
> 756	      xfree (p);
> 
> etc. I can even do:
> 
> (gdb) c 1000
> Will ignore next 999 crossings of breakpoint 1.  Continuing.
> 
> Breakpoint 4, bidi_unshelve_cache (databuf=0x7fffe19ce010, just_free=true) at ../../trunk/src/bidi.c:756
> 756	      xfree (p);
> 
> and the cursor is not moved yet.

Thanks.  That's the "infloop" I described in my other message.  It
should disappear if you try one of the "remedies" I described there.