diff options
| -rw-r--r-- | 68kinst.c | 51 |
1 files changed, 37 insertions, 14 deletions
@@ -274,6 +274,14 @@ uint8_t m68k_valid_immed_limited_dst(m68k_op_info *dst) return 1; } +uint8_t m68k_valid_movem_dst(m68k_op_info *dst) +{ + if (dst->addr_mode == MODE_REG || dst->addr_mode == MODE_AREG_POSTINC) { + return 0; + } + return m68k_valid_immed_limited_dst(dst); +} + uint16_t *m68k_decode_op(uint16_t *cur, uint8_t size, m68k_op_info *dst) { uint8_t mode = (*cur >> 3) & 0x7; @@ -346,7 +354,10 @@ uint16_t * m68k_decode(uint16_t * istream, m68kinst * decoded, uint32_t address) decoded->src.params.regs.pri = m68k_reg_quick_field(*istream); decoded->extra.size = OPSIZE_BYTE; istream = m68k_decode_op(istream, decoded->extra.size, &(decoded->dst)); - if (!istream) { + if ( + !istream || decoded->dst.addr_mode == MODE_AREG + || (decoded->op != M68K_BTST && !m68k_valid_immed_limited_dst(&decoded->dst)) + ) { decoded->op = M68K_INVALID; break; } @@ -376,7 +387,7 @@ uint16_t * m68k_decode(uint16_t * istream, m68kinst * decoded, uint32_t address) decoded->src.params.immed = *(++istream) & 0xFF; decoded->extra.size = OPSIZE_BYTE; istream = m68k_decode_op_ex(istream, opmode, reg, decoded->extra.size, &(decoded->dst)); - if (!istream) { + if (!istream || !m68k_valid_immed_dst(&decoded->dst)) { decoded->op = M68K_INVALID; break; } @@ -521,6 +532,9 @@ uint16_t * m68k_decode(uint16_t * istream, m68kinst * decoded, uint32_t address) break; case 4: //BTST, BCHG, BCLR, BSET + //Seems like this should be unnecessary since bit instructions are explicitly handled above + //Possible this is redundant or the case above is overly restrictive + //TODO: Investigate whether this can be removed switch ((*istream >> 6) & 0x3) { case 0: @@ -536,10 +550,13 @@ uint16_t * m68k_decode(uint16_t * istream, m68kinst * decoded, uint32_t address) decoded->op = M68K_BSET; break; } - decoded->src.addr_mode = MODE_IMMEDIATE; + decoded->src.addr_mode = MODE_IMMEDIATE_WORD; decoded->src.params.immed = *(++istream) & 0xFF; istream = m68k_decode_op(istream, OPSIZE_BYTE, &(decoded->dst)); - if (!istream) { + if ( + !istream || !m68k_valid_immed_dst(&decoded->dst) + || (decoded->op != M68K_BTST && !m68k_valid_immed_limited_dst(&decoded->dst)) + ) { decoded->op = M68K_INVALID; break; } @@ -643,7 +660,7 @@ uint16_t * m68k_decode(uint16_t * istream, m68kinst * decoded, uint32_t address) break; } istream = m68k_decode_op_ex(istream, opmode, reg, decoded->extra.size, &(decoded->dst)); - if (!istream || decoded->dst.addr_mode == MODE_IMMEDIATE) { + if (!istream || decoded->dst.addr_mode > MODE_ABSOLUTE || (decoded->dst.addr_mode == MODE_AREG && optype == MOVE_BYTE)) { decoded->op = M68K_INVALID; break; } @@ -681,7 +698,7 @@ uint16_t * m68k_decode(uint16_t * istream, m68kinst * decoded, uint32_t address) decoded->dst.addr_mode = MODE_REG; decoded->dst.params.regs.pri = m68k_reg_quick_field(*istream); istream = m68k_decode_op(istream, decoded->extra.size, &(decoded->src)); - if (!istream) { + if (!istream || decoded->src.addr_mode == MODE_AREG) { decoded->op = M68K_INVALID; break; } @@ -708,7 +725,7 @@ uint16_t * m68k_decode(uint16_t * istream, m68kinst * decoded, uint32_t address) decoded->src.addr_mode = MODE_REG; decoded->src.params.immed = *(++istream); istream = m68k_decode_op_ex(istream, opmode, reg, decoded->extra.size, &(decoded->dst)); - if (!istream) { + if (!istream || !m68k_valid_movem_dst(&decoded->dst)) { decoded->op = M68K_INVALID; break; } @@ -728,7 +745,7 @@ uint16_t * m68k_decode(uint16_t * istream, m68kinst * decoded, uint32_t address) } decoded->extra.size = size; istream= m68k_decode_op(istream, size, &(decoded->dst)); - if (!istream) { + if (!istream || !m68k_valid_immed_limited_dst(&decoded->dst)) { decoded->op = M68K_INVALID; break; } @@ -747,7 +764,7 @@ uint16_t * m68k_decode(uint16_t * istream, m68kinst * decoded, uint32_t address) } decoded->extra.size = size; istream= m68k_decode_op(istream, size, &(decoded->dst)); - if (!istream) { + if (!istream || !m68k_valid_immed_limited_dst(&decoded->dst)) { decoded->op = M68K_INVALID; break; } @@ -758,14 +775,14 @@ uint16_t * m68k_decode(uint16_t * istream, m68kinst * decoded, uint32_t address) decoded->op = M68K_MOVE_CCR; size = OPSIZE_WORD; istream= m68k_decode_op(istream, size, &(decoded->src)); - if (!istream) { + if (!istream || decoded->src.addr_mode == MODE_AREG) { decoded->op = M68K_INVALID; break; } } else { decoded->op = M68K_NEG; istream= m68k_decode_op(istream, size, &(decoded->dst)); - if (!istream) { + if (!istream || !m68k_valid_immed_limited_dst(&decoded->dst)) { decoded->op = M68K_INVALID; break; } @@ -778,14 +795,14 @@ uint16_t * m68k_decode(uint16_t * istream, m68kinst * decoded, uint32_t address) decoded->op = M68K_MOVE_SR; size = OPSIZE_WORD; istream= m68k_decode_op(istream, size, &(decoded->src)); - if (!istream) { + if (!istream || decoded->src.addr_mode == MODE_AREG) { decoded->op = M68K_INVALID; break; } } else { decoded->op = M68K_NOT; istream= m68k_decode_op(istream, size, &(decoded->dst)); - if (!istream) { + if (!istream || !m68k_valid_immed_limited_dst(&decoded->dst)) { decoded->op = M68K_INVALID; break; } @@ -840,7 +857,7 @@ uint16_t * m68k_decode(uint16_t * istream, m68kinst * decoded, uint32_t address) decoded->op = M68K_NBCD; decoded->extra.size = OPSIZE_BYTE; istream = m68k_decode_op(istream, OPSIZE_BYTE, &(decoded->dst)); - if (!istream) { + if (!istream || !m68k_valid_immed_limited_dst(&decoded->dst)) { decoded->op = M68K_INVALID; break; } @@ -884,6 +901,12 @@ uint16_t * m68k_decode(uint16_t * istream, m68kinst * decoded, uint32_t address) decoded->op = M68K_INVALID; break; } +#ifndef M68020 + if (!m68k_valid_immed_limited_dst(&decoded->src)) { + decoded->op = M68K_INVALID; + break; + } +#endif } } break; |