Mercurial > repos > blastem
diff m68k.cpu @ 2478:ea37200967c7
Implement lea and pea in new 68K core
| author | Michael Pavone <pavone@retrodev.com> |
|---|---|
| date | Thu, 07 Mar 2024 00:53:11 -0800 |
| parents | f171a12fc98c |
| children | 29baf8d5a579 |
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--- a/m68k.cpu Tue Mar 05 23:23:06 2024 -0800 +++ b/m68k.cpu Thu Mar 07 00:53:11 2024 -0800 @@ -1737,6 +1737,87 @@ ror dregs.R 16 dregs.R update_flags NZV0C0 m68k_prefetch + +m68k_calc_ea + arg mode 16 + arg reg 16 + + switch mode + case 2 + #address reg indirect + meta ea aregs.reg + case 5 + #displacement + m68k_prefetch + sext 32 prefetch scratch1 + scratch1 += aregs.reg + meta ea scratch1 + case 6 + #index + m68k_index_word + cycles 4 + scratch1 += aregs.reg + meta ea scratch1 + case 7 + switch reg + case 0 + #absolute short + m68k_prefetch + sext 32 prefetch scratch1 + case 1 + #absoltue long + m68k_prefetch + scratch2 = prefetch << 16 + m68k_prefetch + scratch1 = scratch2 | prefetch + case 2 + #pc displacement + m68k_prefetch + sext 32 prefetch scratch1 + scratch1 += pc + scratch1 -= 2 + case 3 + #pc indexed + m68k_index_word + cycles 4 + scratch1 += pc + scratch1 -= 2 + end + meta ea scratch1 + end + +0100100001MMMRRR pea + invalid M 0 + invalid M 1 + invalid M 3 + invalid M 4 + invalid M 7 R 4 + invalid M 7 R 5 + invalid M 7 R 6 + invalid M 7 R 7 + + m68k_calc_ea M R + scratch2 = a7 - 4 + m68k_write32_lowfirst ea + a7 -= 4 + + m68k_prefetch + +0100DDD111MMMRRR lea + invalid M 0 + invalid M 1 + invalid M 3 + invalid M 4 + invalid M 7 R 4 + invalid M 7 R 5 + invalid M 7 R 6 + invalid M 7 R 7 + + m68k_calc_ea M R + aregs.D = ea + + m68k_prefetch + 0100111001110000 reset if reset_handler