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Fixed V20 / V30 MUL flags - OpenXT now correctly detects the V20.

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OBattler
2022-10-26 17:02:52 +02:00
parent 3f34ced764
commit 605929fcba
1 changed files with 7 additions and 5 deletions
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12
src/cpu/808x.c
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@@ -1405,8 +1405,7 @@ set_co_mul(int bits, int carry)
{
set_cf(carry);
set_of(carry);
if (!is_nec)
set_zf_ex(!carry);
set_zf_ex(!carry);
if (!carry)
wait(1, 0);
}
@@ -1654,7 +1653,7 @@ execx86(int cycs)
uint16_t addr, tempw, new_cs, new_ip;
uint16_t tempw_int, size, tempbp, lowbound;
uint16_t highbound, regval, orig_sp, wordtopush;
uint16_t immediate;
uint16_t immediate, old_flags;
int bits;
uint32_t dest_seg, i, carry, nibble;
uint32_t srcseg, byteaddr;
@@ -3359,6 +3358,7 @@ execx86(int cycs)
break;
case 0x20: /* MUL */
case 0x28: /* IMUL */
old_flags = cpu_state.flags;
wait(1, 0);
mul(get_accum(bits), cpu_data);
if (opcode & 1) {
@@ -3373,12 +3373,14 @@ execx86(int cycs)
if (!is_nec)
cpu_data = AH;
}
/* NOTE: When implementing the V20, care should be taken to not change
the zero flag. */
set_sf(bits);
set_pf();
if (cpu_mod != 3)
wait(1, 0);
/* NOTE: When implementing the V20, care should be taken to not change
the zero flag. */
if (is_nec)
cpu_state.flags = (cpu_state.flags & ~Z_FLAG) | (old_flags & Z_FLAG);
break;
case 0x30: /* DIV */
case 0x38: /* IDIV */