Re: [Emacs-diffs] comment-cache 223d16f 2/3: Apply `comment-depth' text properties when calling `back_comment'.

[martin rudalics]

> Here are my results, with today's emacs-25 and master:
>
>              emacs-25     master    emacs-25.0.92    emacs-23.3
> foo          33.375       33.89       2.859            1.375
> bar         213.250      213.578     15.547            8.625
>
> The two former versions are compiled the same as Martin's, but without
> "--enable-check-lisp-object-type=yes".  The two latter versions are
> optimized builds, and emacs-23.3 is (of course) without --wide-int.
>
> Also note that I killed the buffer visiting xdisp.c between testing
> 'foo' and 'bar'.
>
> Martin, could it be that --enable-check-lisp-object-type=yes makes
> such a big difference on your system?

I don't think so.  I currently switched all my debug builds to -O2 so
that I can at least do some practical work with the release version and
got the following results:


Emacs-25 CFLAGS='-O2 -g3 -gdwarf-2' --with-wide-int --enable-checking=yes 
--enable-check-lisp-object-type=yes

c-end-of-defun          365         5.3909999999  0.0147698630
c-beginning-of-defun    365        28.921999999   0.0792383561


Emacs-25 CFLAGS='-O2 -g3 -gdwarf-2' --with-wide-int --enable-checking=yes

c-end-of-defun          365         5.3599999999  0.0146849315
c-beginning-of-defun    365        28.906999999   0.0791972602


comment-cache CFLAGS='-O2 -g3 -gdwarf-2' --with-wide-int --enable-checking=yes 
--enable-check-lisp-object-type=yes

c-end-of-defun          365         3.8270000000  0.0104849315
c-beginning-of-defun    365        28.499999999   0.0780821917


master CFLAGS='-O2 -g3 -gdwarf-2' --with-wide-int --enable-checking=yes 
--enable-check-lisp-object-type=yes

c-end-of-defun          365         5.7809999999  0.0158383561
c-beginning-of-defun    365        29.608999999   0.0811205479


master CFLAGS='-O3'

c-end-of-defun          365         3.9530000000  0.0108301369
c-beginning-of-defun    365        20.124999999   0.0551369863


The only remarkable difference I see is that c-end-of-defun with the
comment-cache version is significantly faster.  The values for the
relatively slow c-beginning-of-defun practically don't change unless I
build without debugging information.

martin