CHIP_IO_BTAG_COUNT
static struct vmem_btag __C(CHIP,_io_btag_store)[CHIP_IO_BTAG_COUNT(xxx)];
vmem_add_bts(vm, CHIP_IO_BTAG_STORE(v), CHIP_IO_BTAG_COUNT(v));
static struct vmem_btag __C(CHIP,_io_btag_store)[CHIP_IO_BTAG_COUNT(xxx)];
vmem_add_bts(vm, CHIP_IO_BTAG_STORE(v), CHIP_IO_BTAG_COUNT(v));