Mercurial > repos > blastem
diff 68kinst.c @ 61:918468c623e9
Add support for BTST instruction (untested), absolute addressing mode for instructions other than move (untested) and fix decoding of MOVEM.
| author | Mike Pavone <pavone@retrodev.com> |
|---|---|
| date | Wed, 19 Dec 2012 20:23:59 -0800 |
| parents | 6ffea8607730 |
| children | b37cb596bc21 |
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--- a/68kinst.c Tue Dec 18 23:55:10 2012 -0800 +++ b/68kinst.c Wed Dec 19 20:23:59 2012 -0800 @@ -124,8 +124,11 @@ } decoded->src.addr_mode = MODE_REG; decoded->src.params.regs.pri = m68k_reg_quick_field(*istream); - decoded->extra.size = OPSIZE_LONG; - istream = m68k_decode_op(istream, OPSIZE_LONG, &(decoded->dst)); + decoded->extra.size = OPSIZE_BYTE; + istream = m68k_decode_op(istream, decoded->extra.size, &(decoded->dst)); + if (decoded->dst.addr_mode == MODE_REG) { + decoded->extra.size = OPSIZE_LONG; + } } else if ((*istream & 0xF00) == 0x800) { //BTST, BCHG, BCLR, BSET switch ((*istream >> 6) & 0x3) @@ -145,10 +148,13 @@ } opmode = (*istream >> 3) & 0x7; reg = *istream & 0x7; - decoded->src.addr_mode = MODE_IMMEDIATE; + decoded->src.addr_mode = MODE_IMMEDIATE_WORD; decoded->src.params.immed = *(++istream) & 0xFF; decoded->extra.size = OPSIZE_BYTE; - istream = m68k_decode_op_ex(istream, opmode, reg, OPSIZE_BYTE, &(decoded->dst)); + istream = m68k_decode_op_ex(istream, opmode, reg, decoded->extra.size, &(decoded->dst)); + if (decoded->dst.addr_mode == MODE_REG) { + decoded->extra.size = OPSIZE_LONG; + } } else if ((*istream & 0xC0) == 0xC0) { #ifdef M68020 //CMP2, CHK2, CAS, CAS2, RTM, CALLM @@ -407,7 +413,8 @@ decoded->dst.addr_mode = m68k_reg_quick_field(*istream); } else { opmode = (*istream >> 3) & 0x7; - if ((*istream & 0xB80) == 0x880 && opmode != MODE_REG && opmode != MODE_AREG && opmode != MODE_AREG_POSTINC) { + if ((*istream & 0xB80) == 0x880 && opmode != MODE_REG && opmode != MODE_AREG) { + //TODO: Check for invalid modes that are dependent on direction decoded->op = M68K_MOVEM; decoded->extra.size = *istream & 0x40 ? OPSIZE_LONG : OPSIZE_WORD; reg = *istream & 0x7; @@ -1143,6 +1150,7 @@ case MODE_AREG_DISPLACE: return sprintf(dst, "%s (a%d, %d)", c, decoded->params.regs.pri, decoded->params.regs.displacement); case MODE_IMMEDIATE: + case MODE_IMMEDIATE_WORD: return sprintf(dst, "%s #%d", c, decoded->params.immed); case MODE_ABSOLUTE_SHORT: return sprintf(dst, "%s $%X.w", c, decoded->params.immed);