diff options
| author | Mike Pavone <pavone@retrodev.com> | 2012-11-04 23:43:03 -0800 |
|---|---|---|
| committer | Mike Pavone <pavone@retrodev.com> | 2012-11-04 23:43:03 -0800 |
| commit | 0367e645f265500fc0988dfb0bc2c1141252fa71 (patch) | |
| tree | 786c90e3b497f9a9687f3b238d65c4b4021d2851 /68kinst.c | |
| parent | 89bcfa1995c34802321e19a244d9b3d025c1ad39 (diff) | |
Add support for some bit instructions and a few others in the same "category"
Diffstat (limited to '68kinst.c')
| -rw-r--r-- | 68kinst.c | 82 |
1 files changed, 81 insertions, 1 deletions
@@ -95,6 +95,8 @@ uint16_t * m68K_decode(uint16_t * istream, m68kinst * decoded) { uint8_t optype = *istream >> 12; uint8_t size; + uint8_t reg; + uint8_t opmode; uint32_t immed; decoded->op = M68K_INVALID; decoded->src.addr_mode = decoded->dst.addr_mode = MODE_UNUSED; @@ -102,7 +104,85 @@ uint16_t * m68K_decode(uint16_t * istream, m68kinst * decoded) switch(optype) { case BIT_MOVEP_IMMED: - //TODO: Implement me + if (*istream & 0x100) { + //BTST, BCHG, BCLR, BSET + switch ((*istream >> 6) & 0x3) + { + case 0: + decoded->op = M68K_BTST; + break; + case 1: + decoded->op = M68K_BCHG; + break; + case 2: + decoded->op = M68K_BCLR; + break; + case 3: + decoded->op = M68K_BSET; + break; + } + decoded->src.addr_mode = MODE_REG; + decoded->src.params.regs.pri = m68K_reg_quick_field(*istream); + istream = m68k_decode_op(istream, OPSIZE_LONG, &(decoded->dst)); + } else { + switch ((*istream >> 9) & 0x7) + { + case 0: + if ((*istream & 0xFF) == 0x3C) { + decoded->op = M68K_ORI_CCR; + decoded->extra.size = OPSIZE_BYTE; + decoded->src.addr_mode = MODE_IMMEDIATE; + decoded->src.params.u8 = *(++istream); + } else if((*istream & 0xFF) == 0x7C) { + decoded->op = M68K_ORI_SR; + decoded->extra.size = OPSIZE_WORD; + decoded->src.addr_mode = MODE_IMMEDIATE; + decoded->src.params.u16 = *(++istream); + } else { + //ORI, CMP2.b, CHK2.b + if ((*istream & 0xC0) != 0xC0) { + decoded->op = M68K_OR; + decoded->src.addr_mode = MODE_IMMEDIATE; + decoded->extra.size = size = (*istream >> 6) & 3; + reg = *istream & 0x7; + opmode = (*istream >> 3) & 0x7; + switch (size) + { + case OPSIZE_BYTE: + decoded->src.params.u8 = *(++istream); + break; + case OPSIZE_WORD: + decoded->src.params.16 = *(++istream); + break; + case OPSIZE_LONG: + immed = *(++istream); + decoded->src.params.u32 = immed << 16 | *(++istream); + break; + } + istream = m68k_decode_op_ex(istream, opmode, reg, size, &(decoded->dst)); + } else { + #ifdef M68020 + //TODO: Implement me for 68020 support + #endif + } + } + break; + case 1: + break; + case 2: + break; + case 3: + break; + case 4: + break; + case 5: + break; + case 6: + break; + case 7: + break; + } + } break; case MOVE_BYTE: case MOVE_LONG: |