Fix bug #9771 with slow redisplay in long lines full of control characters.
src/bidi.c (bidi_line_init): Initialize next_en_pos to zero, not -1. (bidi_resolve_neutral): Don't enter the expensive loop looking for non-neutral characters if the current character is a paragraph separator (a.k.a. Newline). This avoids running the same expensive loop twice, once when we consume the preceding newline and the other time when the line actually needs to be displayed. Avoid the loop when we see neutrals on the base embedding level following a character whose directionality is the same as the paragraph's. This avoids running the expensive loop when a line ends in a long sequence of neutrals, like control characters. Add assertion against STRONG_AL type. Slightly rearrange code that determines the type of a neutral given the first non-neutral that follows it. (bidi_level_of_next_char): Set next_en_pos to zero when invalidating its info.
Showing with 68 additions and 10 deletions