+#ifdef RSAZ_ENABLED
+ /*
+ * If the size of the operands allow it, perform the optimized
+ * RSAZ exponentiation. For further information see
+ * crypto/bn/rsaz_exp.c and accompanying assembly modules.
+ */
+ if ((16 == a->top) && (16 == p->top) && (BN_num_bits(m) == 1024)
+ && rsaz_avx2_eligible())
+ {
+ if (NULL == bn_wexpand(rr, 16)) goto err;
+ RSAZ_1024_mod_exp_avx2(rr->d, a->d, p->d, m->d, mont->RR.d, mont->n0[0]);
+ rr->top = 16;
+ rr->neg = 0;
+ bn_correct_top(rr);
+ ret = 1;
+ goto err;
+ }
+ else if ((8 == a->top) && (8 == p->top) && (BN_num_bits(m) == 512))
+ {
+ if (NULL == bn_wexpand(rr,8)) goto err;
+ RSAZ_512_mod_exp(rr->d, a->d, p->d, m->d, mont->n0[0], mont->RR.d);
+ rr->top = 8;
+ rr->neg = 0;
+ bn_correct_top(rr);
+ ret = 1;
+ goto err;
+ }
+#endif
+