+ /* --- If this is not the low-order word then note final-pass start --- *
+ *
+ * Once we've eliminated the whole high-degree words, there will possibly
+ * remain a few high-degree bits. We can further reduce the subject
+ * polynomial by subtracting an appropriate multiple of %$p'$%, but if we
+ * do this naively we'll end up addressing `low-order' words beyond the
+ * bottom of our input. We solve this problem by storing an alternative
+ * start position for this final pass (which works because we scan bits
+ * right-to-left).
+ */
+
+ if (!(g->f & f_fip) && w < g->r->lim) {
+ g->fip = DA_LEN(&g->iv);
+ g->f |= f_fip;
+ }
+
+ /* --- Actually emit the instruction --- */
+