BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SETNLE_EbR(bxInstruction_c *i)
{
Bit8u result_8 = !(getB_ZF() | (getB_SF() ^ getB_OF()));
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), result_8);
BX_NEXT_INSTR(i);
}
void BX_CPU_C::XCHG_EbGb(bxInstruction_c *i)
{
Bit8u op2, op1;
op2 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
/* op1 is a register or memory reference */
if (i->modC0()) {
op1 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), op2);
}
else {
/* pointer, segment address pair */
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1);
write_RMW_virtual_byte(op2);
}
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), op1);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::DEC_EbR(bxInstruction_c *i)
{
Bit32u op1_8 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
op1_8--;
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), op1_8);
SET_FLAGS_OSZAP_SUB_8(op1_8 + 1, 0, op1_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EbR(bxInstruction_c *i)
{
Bit32u op1_8 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
op1_8 = - (Bit8s)(op1_8);
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), op1_8);
SET_FLAGS_OSZAPC_SUB_8(0, 0 - op1_8, op1_8);
BX_NEXT_INSTR(i);
}
void BX_CPU_C::MOV_EbIb(bxInstruction_c *i)
{
Bit8u op2 = i->Ib();
if (i->modC0()) {
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), op2);
}
else {
write_virtual_byte(i->seg(), RMAddr(i), &op2);
}
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SBB_EbIbR(bxInstruction_c *i)
{
Bit32u op1_8 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u op2_8 = i->Ib();
Bit32u diff_8 = op1_8 - (op2_8 + getB_CF());
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), diff_8);
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ADC_GbEbR(bxInstruction_c *i)
{
Bit32u op1 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u op2 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u sum = op1 + op2 + getB_CF();
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), sum);
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::XADD_EbGbR(bxInstruction_c *i)
{
/* XADD dst(r/m8), src(r8)
* temp <-- src + dst | sum = op2 + op1
* src <-- dst | op2 = op1
* dst <-- tmp | op1 = sum
*/
Bit32u op1 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u op2 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u sum = op1 + op2;
// and write destination into source
// Note: if both op1 & op2 are registers, the last one written
// should be the sum, as op1 & op2 may be the same register.
// For example: XADD AL, AL
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), op1);
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), sum);
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
void BX_CPU_C::SETNB_Eb(bxInstruction_c *i)
{
Bit8u result_8;
if (get_CF()==0)
result_8 = 1;
else
result_8 = 0;
/* now write result back to destination */
if (i->modC0()) {
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), result_8);
}
else {
write_virtual_byte(i->seg(), RMAddr(i), &result_8);
}
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::CMPXCHG_EbGbR(bxInstruction_c *i)
{
Bit32u op1_8 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u diff_8 = AL - op1_8;
SET_FLAGS_OSZAPC_SUB_8(AL, op1_8, diff_8);
if (diff_8 == 0) { // if accumulator == dest
// dest <-- src
Bit32u op2_8 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), op2_8);
}
else {
// accumulator <-- dest
AL = op1_8;
}
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::XADD_EbGbM(bxInstruction_c *i)
{
/* XADD dst(r/m8), src(r8)
* temp <-- src + dst | sum = op2 + op1
* src <-- dst | op2 = op1
* dst <-- tmp | op1 = sum
*/
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1 = read_RMW_virtual_byte(i->seg(), eaddr);
Bit32u op2 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u sum = op1 + op2;
write_RMW_virtual_byte(sum);
/* and write destination into source */
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), op1);
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SETNB_EbR(bxInstruction_c *i)
{
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), !getB_CF());
BX_NEXT_INSTR(i);
}
void BX_CPU_C::MOV_GbEGb(bxInstruction_c *i)
{
Bit8u op2 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), op2);
}