up1
if (kl<=1 && i>0 && allh(up1(i)))
kl = c>0 ? thish(up1(i),c-1) : 0;
if (kr<=1 && i>0 && allh(up1(i)))
kr = c>0 ? thish(up1(i), c) : 0;
UpVal **up1 = getupvalref(L, fidx1, n1, &f1);
*up1 = *up2;