regcomp.c: Improve generated code for some [:posix:] classes

For regexes compiled not under /l, [:posix:] classes in general require
special handling, as
    1) under /d they can match two different sets of code points,
       depending on whether or not the target string is in UTF-8.
    2) under /a, the matches above the ASCII range need to be filtered
       out.
But note that nothing special is needed for /u, and under [:ascii:],
there is nothing to be filtered out, and the UTF-8ness of the target
doesn't matter either.  And since [:digit:] and [:xdigit:] don't have
matches in the upper Latin1 range, under /d the UTF-8ness doesn't matter
for them either.

This commit skips the special handling for the above conditions.  This
leads to less work during pattern compilation, and can mean faster
run-time code, as well, skipping function calls that otherwise would be
done.

0 files changed, 0 insertions, 0 deletions