In article <874ngjl1tw.fsf@gnu.org>, handa <handa@gnu.org> writes:

> The next tuning I am working on is for the case you don't
> specify *-unix explicitly, and also for the case of utf-8
> files (which need no decoding but need character counting).

I've just installed a decoder optimization for a file
without coding: tag and a file with dos-like EOL format.
Here the result of the benchmark test using the attached
Lisp code.  It seems that now Emacs can read ASCII only
files (with or without coding tags, unix-like or dos-like
EOL format) 1.3 to 6.4 times faster.

(benchmark-decoder)
With optimization:
~/tag-utf-8-unix.unix: (0.350511637 0 0.0)
~/tag-utf-8.unix: (0.70990067 0 0.0)
~/tag-none.unix: (0.995416864 0 0.0)
~/tag-utf-8-dos.dos: (1.0152946189999998 0 0.0)
~/tag-utf-8.dos: (1.2202745289999999 0 0.0)
~/tag-none.dos: (1.669854579 0 0.0)
Without optimization:
~/tag-utf-8-unix.unix: (2.239232573 0 0.0)
~/tag-utf-8.unix: (2.307786132 0 0.0)
~/tag-none.unix: (2.572636136 0 0.0)
~/tag-utf-8-dos.dos: (2.6095316459999998 0 0.0)
~/tag-utf-8.dos: (4.839366146000001 0 0.0)
~/tag-none.dos: (2.103833078 0 0.0)

Next work will be an optimization for UTF-8 files containing
non-ASCII characters.

---
Kenichi Handa
handa@gnu.org