LEAVE sets the limit equal to the index: the rest of the body runs with
the index unchanged and the loop ends at the next LOOP or +LOOP. v3's
left the loop at once, which is FORTH-83's.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
(DO) (?DO) (LOOP) (+LOOP) (LEAVE) I J UNLOOP and (0BRANCH), laid down
in line by hand as the compiler will, executed on the golden model at
both cell widths against C on every pair of 14 loop ends and 11 steps,
and against sequences recorded from the v3 binary.
(LOOP) goes round again while index < limit, signed, as v3 does; the
document's equality test differed whenever start >= limit. (+LOOP) is
now specified. J keeps the outer index in A and needs no extra return
entry.
LEAVE discards the limit and index. v3 left them on its return stack,
which made a LEAVE in an inner loop stop the outer one.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>