be64enc_vect
be64enc_vect(&ctx->buf[112], ctx->count, 16);
be64enc_vect(digest, ctx->state, SHA512_DIGEST_LENGTH);
be64enc_vect(digest, ctx->state, SHA512_224_DIGEST_LENGTH);
be64enc_vect(digest, ctx->state, SHA512_256_DIGEST_LENGTH);
be64enc_vect(digest, ctx->state, SHA384_DIGEST_LENGTH);