riscv64/itx: Special case 16x16 8bpc dct_dct eob=0
Current performance comparison:
| SpacemiT K1: | Master branch: | itx_16x16: |
|---|---|---|
| inv_txfm_add_16x16_dct_dct_0_8bpc_c: | 1534.1 ( 1.00x) | 1534.7 ( 1.00x) |
| inv_txfm_add_16x16_dct_dct_0_8bpc_rvv: | 1173.6 ( 1.31x) | 168.0 ( 9.14x) |
| Kendryte K230: | Master branch: | itx_16x16: |
|---|---|---|
| inv_txfm_add_16x16_dct_dct_0_8bpc_c: | 1576.0 ( 1.00x) | 1579.1 ( 1.00x) |
| inv_txfm_add_16x16_dct_dct_0_8bpc_rvv: | 1095.5 ( 1.44x) | 146.8 (10.75x) |
Edited by Bogdan Gligorijević