Function fxBigInt_add

xs/sources/xsBigInt.c:1357–1372

 */

txBigInt *fxBigInt_add(txMachine* the, txBigInt *rr, txBigInt *aa, txBigInt *bb)
{
	if ((aa->sign ^ bb->sign) == 0) {
		rr = fxBigInt_uadd(the, rr, aa, bb);
		if (aa->sign)
			rr->sign = 1;
	}
	else {
		if (!aa->sign)
			rr = fxBigInt_usub(the, rr, aa, bb);
		else
			rr = fxBigInt_usub(the, rr, bb, aa);
	}
	mxBigInt_meter(rr->size);
	return(rr);
}

txBigInt *fxBigInt_dec(txMachine* the, txBigInt *r, txBigInt *a)
{