int32_t instr_movsb(struct emu_cpu *c, struct emu_cpu_instruction *i)
{
if (i->prefixes & PREFIX_OPSIZE ) {
UNIMPLEMENTED(c, SST);
}
if (i->prefixes & PREFIX_F3 || i->prefixes & PREFIX_F2)
{
/* Copy ECX bytes from DS:[ESI] to ES:[EDI] */
if (c->reg[ecx] > 0 )
{
uint8_t tmp;
c->reg[ecx]--;
c->repeat_current_instr = true;
MEM_BYTE_READ(c, c->reg[esi], &tmp);
MEM_BYTE_WRITE(c, c->reg[edi], tmp);
if ( !CPU_FLAG_ISSET(c,f_df) )
{ /* increment */
c->reg[edi] += 1;
c->reg[esi] += 1;
}
else
{ /* decrement */
c->reg[edi] -= 1;
c->reg[esi] -= 1;
}
}
else{
c->repeat_current_instr = false;
}
}
else
{
/* a4 move ds:esi -> es->edi */
uint8_t tmp;
MEM_BYTE_READ(c, c->reg[esi], &tmp);
MEM_BYTE_WRITE(c, c->reg[edi], tmp);
if ( !CPU_FLAG_ISSET(c,f_df) )
{ /* increment */
c->reg[edi] += 1;
c->reg[esi] += 1;
}
else
{ /* decrement */
c->reg[edi] -= 1;
c->reg[esi] -= 1;
}
}
return 0;
}
int32_t instr_group_2_c0_shr(struct emu_cpu *c, struct emu_cpu_instruction *i)
{
if ( i->modrm.mod != 3 )
{
/* C0 /5 ib
* Unsigned divide r/m8 by 2, imm8 times
* SHR r/m8,imm8
*/
uint8_t m8;
MEM_BYTE_READ(c, i->modrm.ea, &m8);
INSTR_CALC_AND_SET_FLAGS(8,
c,
m8,
*i->imm8);
MEM_BYTE_WRITE(c, i->modrm.ea, m8);
}
else
{
/* C0 /5 ib
* Unsigned divide r/m8 by 2, imm8 times
* SHR r/m8,imm8
*/
INSTR_CALC_AND_SET_FLAGS(8,
c,
*c->reg8[i->modrm.rm],
*i->imm8);
}
return 0;
}
int32_t instr_group_3_f6_not(struct emu_cpu *c, struct emu_cpu_instruction *i)
{
if (i->modrm.mod != 3)
{
/* F6 /2
* Reverse each bit of r/m8
* NOT r/m8
*/
uint8_t m8;
MEM_BYTE_READ(c, i->modrm.ea, &m8);
INSTR_CALC_AND_SET_FLAGS(8,
c,
m8)
MEM_BYTE_WRITE(c, i->modrm.ea, m8);
}
else
{
/* F6 /2
* Reverse each bit of r/m8
* NOT r/m8
*/
INSTR_CALC_AND_SET_FLAGS(8,c,*c->reg8[i->modrm.rm]);
}
return 0;
}
int32_t instr_group_2_c0_rcl(struct emu_cpu *c, struct emu_cpu_instruction *i)
{
if ( i->modrm.mod != 3 )
{
/* C0 /2 ib
* Rotate nine bits (CF,r/m8) left imm8 times
* RCL r/m8,imm8
*/
uint8_t m8;
MEM_BYTE_READ(c, i->modrm.ea, &m8);
INSTR_CALC_AND_SET_FLAGS(8,
c,
m8,
*i->imm8);
MEM_BYTE_WRITE(c, i->modrm.ea, m8);
}
else
{
/* C0 /2 ib
* Rotate nine bits (CF,r/m8) left imm8 times
* RCL r/m8,imm8
*/
INSTR_CALC_AND_SET_FLAGS(8,
c,
*c->reg8[i->modrm.rm],
*i->imm8);
}
return 0;
}
int32_t instr_group_3_f6_neg(struct emu_cpu *c, struct emu_cpu_instruction *i)
{
if ( i->modrm.mod != 3 )
{
/* F6 /3
* Two's complement negate r/m8
* NEG r/m8
*/
uint8_t m8;
MEM_BYTE_READ(c, i->modrm.ea, &m8);
INSTR_CALC_AND_SET_FLAGS(8,
c,
m8)
MEM_BYTE_WRITE(c, i->modrm.ea, m8);
}
else
{
/* F6 /3
* Two's complement negate r/m8
* NEG r/m8
*/
INSTR_CALC_AND_SET_FLAGS(8,c,*c->reg8[i->modrm.rm]);
}
return 0;
}
int32_t instr_group_2_d2_sal(struct emu_cpu *c, struct emu_cpu_instruction *i)
{
if ( i->modrm.mod != 3 )
{
/* D2 /4
* Multiply r/m8 by 2, CL times
* SAL r/m8,CL
*/
uint8_t m8;
MEM_BYTE_READ(c, i->modrm.ea, &m8);
INSTR_CALC_AND_SET_FLAGS(8,
c,
m8,
*c->reg8[cl]);
MEM_BYTE_WRITE(c, i->modrm.ea, m8);
}
else
{
/* D2 /4
* Multiply r/m8 by 2, CL times
* SAL r/m8,CL
*/
INSTR_CALC_AND_SET_FLAGS(8,
c,
*c->reg8[i->modrm.rm],
*c->reg8[cl]);
}
return 0;
}
int32_t instr_group_2_d0_sar(struct emu_cpu *c, struct emu_cpu_instruction *i)
{
if ( i->modrm.mod != 3 )
{
/* D0 /7
* Signed divide* r/m8 by 2, once
* SAR r/m8,1
*/
uint8_t m8;
MEM_BYTE_READ(c, i->modrm.ea, &m8);
INSTR_CALC_AND_SET_FLAGS(8,
c,
m8,
1);
MEM_BYTE_WRITE(c, i->modrm.ea, m8);
}
else
{
/* D0 /7
* Signed divide* r/m8 by 2, once
* SAR r/m8,1
*/
INSTR_CALC_AND_SET_FLAGS(8,
c,
*c->reg8[i->modrm.rm],
1);
}
return 0;
}
int32_t instr_group_2_d2_rcr(struct emu_cpu *c, struct emu_cpu_instruction *i)
{
if ( i->modrm.mod != 3 )
{
/* D2 /3
* Rotate nine bits (CF,r/m8) right CL times
* RCR r/m8,CL
*/
uint8_t m8;
MEM_BYTE_READ(c, i->modrm.ea, &m8);
INSTR_CALC_AND_SET_FLAGS(8,
c,
m8,
*c->reg8[cl]);
MEM_BYTE_WRITE(c, i->modrm.ea, m8);
}
else
{
/* D2 /3
* Rotate nine bits (CF,r/m8) right CL times
* RCR r/m8,CL
*/
INSTR_CALC_AND_SET_FLAGS(8,
c,
*c->reg8[i->modrm.rm],
*c->reg8[cl]);
}
return 0;
}
int32_t instr_mov_a2(struct emu_cpu *c, struct emu_cpu_instruction *i)
{
/* A2
* Move AL to (seg:offset)
* MOV moffs8*,AL
*/
MEM_BYTE_WRITE(c, i->imm, *c->reg8[al]);
return 0;
}
int32_t instr_mov_88(struct emu_cpu *c, struct emu_cpu_instruction *i)
{
/* 88 /r
* Move r8 to r/m8
* MOV r/m8,r8
*/
if( i->modrm.mod != 3 )
{
MEM_BYTE_WRITE(c, i->modrm.ea, *c->reg8[i->modrm.opc]);
}
else
{
*c->reg8[i->modrm.rm] = *c->reg8[i->modrm.opc];
}
return 0;
}
int32_t instr_mov_c6(struct emu_cpu *c, struct emu_cpu_instruction *i)
{
/* C6 /0
* Move imm8 to r/m8
* MOV r/m8,imm8
*/
if( i->modrm.mod != 3 )
{
MEM_BYTE_WRITE(c, i->modrm.ea, *i->imm8);
}
else
{
*c->reg8[i->modrm.rm] = *i->imm8;
}
return 0;
}
int32_t instr_xor_30(struct emu_cpu *c, struct emu_cpu_instruction *i)
{
////TRACK_INIT_ALL_FLAGS(c->instr);
/* 30 /r
* r/m8 XOR r8
* XOR r/m8,r8
*/
if ( i->modrm.mod != 3 )
{
uint8_t dst;
MEM_BYTE_READ(c, i->modrm.ea, &dst);
INSTR_CALC_AND_SET_FLAGS(8,
c,
dst,
*c->reg8[i->modrm.opc],
dst,
^)
MEM_BYTE_WRITE(c, i->modrm.ea, dst);
}
int32_t instr_sbb_18(struct emu_cpu *c, struct emu_cpu_instruction *i)
{
TRACK_INIT_ALL_FLAGS(c->instr);
/* 18 /r
* Subtract with borrow r8 from r/m8
* SBB r/m8,r8
*/
if ( i->modrm.mod != 3 )
{
uint8_t dst;
MEM_BYTE_READ(c, i->modrm.ea, &dst);
INSTR_CALC_AND_SET_FLAGS(8,
c,
dst,
*c->reg8[i->modrm.opc],
dst,
-)
MEM_BYTE_WRITE(c, i->modrm.ea, dst);
}
int32_t instr_group_4_fe_inc(struct emu_cpu *c, struct emu_cpu_instruction *i)
{
/* FE /0
* INC r/m8
* Increment r/m byte by 1
*/
if ( i->modrm.mod != 3 )
{
uint8_t dst;
MEM_BYTE_READ(c, i->modrm.ea, &dst);
INSTR_CALC_AND_SET_FLAGS(8, c, dst)
MEM_BYTE_WRITE(c, i->modrm.ea, dst);
}
else
{
INSTR_CALC_AND_SET_FLAGS(8, c, *c->reg8[i->modrm.rm])
}
return 0;
}
