KOS_OP_MATCH_BOUND

• Style: EXTRA (LABEL, RAW, RAW): label, cursor depth, width.

• Stack: [...] -> [..., bound]; jump to a0 with nothing pushed on a miss.

• Semantics: Push a cursor at the position of the cursor at depth a1 whose end is a2 elements before that cursor’s end. A miss when fewer than a2 elements remain.

• Compiler form: Emitted by the match compiler at the start of a repeat, with a2 the minimum width of what follows the repeat in the same sequence, so the repeat’s passes never take an element that suffix needs.