_REG_A0
gr[_REG_A0] = (unsigned long) arg;
gr[_REG_A0 + i] = va_arg(ap, unsigned long);
gr[_REG_A0] = (unsigned long) arg;
gr[_REG_A0] = (uintptr_t) arg;
gr[_REG_A0 + i] = va_arg(ap, __greg_t);
gr[_REG_A0 + i] = va_arg(ap, __greg_t);
gr[_REG_A0 + i] = va_arg(ap, __greg_t);
gr[_REG_A0] = frame->f_regs[A0];
frame->f_regs[A0] = gr[_REG_A0];