Re: emacs-26 eec71eb: Speed up replace-buffer-contents

[Paul Eggert <eggert@cs.ucla.edu>]

Eli Zaretskii wrote:

> If you mean you have an idea for calling rarely_quit or its equivalent
> in a more elegant way (e.g., without a static counter), then it would
> be good, of course.

Yes, that's the idea.

> Which particular problem were did you allude to?

Sorry, I've lost context and don't know what this question refers to.

> It could be that the optimized build will show a different
> picture, although I doubt that.  I might try an optimized build in a
> couple of days (but I never use -O3 in Emacs, only -O2).

Yes, -O2 is what I usually use for benchmarks too, since it's what is normally 
used in production. Its execution profile can differ quite a bit from -O0, due 
to inlining and other things. For rarely_quit, with -O2 typically the overhead 
of the rarely_quit call (including computing its argument) is typically just two 
CPU instructions (a test and a conditional branch that is predicted correctly, 
so both instructions are cheap). This is way better than -O0.