STATIC void
S_more_he(pTHX)
{
    register HE* he;
    register HE* heend;
    XPV *ptr;
    New(54, ptr, 1008/sizeof(XPV), XPV);
    ptr->xpv_pv = (char*)PL_he_arenaroot;
    PL_he_arenaroot = ptr;

    he = (HE*)ptr;
    heend = &he[1008 / sizeof(HE) - 1];
    PL_he_root = ++he;
    while (he < heend) {
        HeNEXT(he) = (HE*)(he + 1);
        he++;
    }
    HeNEXT(he) = 0;
}