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Implement more NEC V20/V30 and 8018x instructions (#3)

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* Implement more NEC V20/V30 and 8018x instructions

* PUSHA/PUSH R
* POPA/POP R
* RO(L/R)4 r/m (NEC only)

* Fix critical mistake
This commit is contained in:
Cacodemon345
2022-09-04 22:30:21 +06:00
committed by GitHub
parent 18d15758f5
commit 71dde8658b
1 changed files with 74 additions and 0 deletions
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74
src/cpu/808x.c
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@@ -1680,6 +1680,7 @@ execx86(int cycs)
{
uint8_t temp = 0, temp2;
uint8_t old_af;
uint8_t handled = 0;
uint16_t addr, tempw;
uint16_t new_cs, new_ip;
int bits;
@@ -1708,6 +1709,52 @@ execx86(int cycs)
push(&(_opseg[(opcode >> 3) & 0x03]->seg));
break;
case 0x07: case 0x0F: case 0x17: case 0x1F: /* POP seg */
if (is_nec && opcode == 0x0F) {
uint8_t orig_opcode = opcode;
opcode = pfq_fetchb();
switch (opcode) {
case 0x28: /* ROL4 r/m */
{
do_mod_rm();
wait(22, 0);
{
uint8_t temp_val = geteab();
uint8_t temp_al = AL;
temp_al &= 0xF;
temp_al |= (temp_val & 0xF0);
temp_val = (temp_al & 0xF) | ((temp_val & 0xF) << 4);
temp_al >>= 4;
temp_al &= 0xF;
seteab(temp_val);
AL = temp_al;
}
handled = 1;
break;
}
case 0x2a: /* ROR4 r/m */
{
do_mod_rm();
wait(22, 0);
{
uint8_t temp_val = geteab();
uint8_t temp_al = AL;
AL = temp_val & 0xF;
temp_val = (temp_val >> 4) | ((temp_al & 0xF) << 4);
seteab(temp_val);
}
handled = 1;
break;
}
default: {
opcode = orig_opcode;
break;
}
}
} else handled = 0;
if (handled) break;
access(22, 16);
if (opcode == 0x0F) {
load_cs(pop());
@@ -1895,8 +1942,35 @@ execx86(int cycs)
break;
case 0x60: /*JO alias*/
if (is186) { /* PUSHA/PUSH R*/
uint16_t orig_sp = SP;
wait(1, 0);
push(&AX);
push(&CX);
push(&DX);
push(&BX);
push(&orig_sp);
push(&BP);
push(&SI);
push(&DI);
}
else jcc(opcode, cpu_state.flags & V_FLAG);
break;
case 0x70: /*JO*/
case 0x61: /*JNO alias*/
if (is186) { /* POPA/POP R*/
uint16_t orig_sp = 0; /* deliberately unused. */
wait(9, 0);
DI = pop();
SI = pop();
BP = pop();
orig_sp = pop();
BX = pop();
DX = pop();
CX = pop();
AX = pop();
break;
}
case 0x71: /*JNO*/
jcc(opcode, cpu_state.flags & V_FLAG);
break;