Re: __builtin_expect used in regex

[Paul Eggert]

On 10/1/18 11:31 AM, address@hidden wrote:
> Those changes look really excessive to me. I prefer to not have to
> keep including more and more files from gnulib just to compile regex
> or dfa.

Sorry, I didn't read your message (I had misfiled it) until just now, 
after I propagated the patch into glibc. So now I will have to go into 
repair mode....

I would rather minimize the difference from glibc. Is this the only 
place where the Gawk regex code departs from the Gnulib copy? If so, 
let's try to come up with a way to keep the source identical, if only by 
using "#ifdef _LIBC" or "#ifdef GAWK" or whatever.


> (As a side point, does all the __builtin_expect / __glibc_unlikely
> stuff *really* make that much difference?  It sure clutters up
> the code unmercifully.)

I agree. I don't think they make much performance difference nowadays. I 
plan to time them and see if we're right; if so, let's get rid of them 
(in glibc regex, Gnulib, and in Gawk).