The MMA produces 128 rows × 128 cols = 4 row-groups × 128 TMEM cols = 512 total. Even though we only read rows 0-63, the MMA writes all 128 rows. TMEM_COLS must match the MMA output size, not just the read size.
The MMA produces 128 rows × 128 cols = 4 row-groups × 128 TMEM cols = 512 total. Even though we only read rows 0-63, the MMA writes all 128 rows. TMEM_COLS must match the MMA output size, not just the read size.