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286: Make LOCK legal with all instructions, per the Programmers' Reference Manual.

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OBattler
2024-06-09 19:58:16 +02:00
parent fbb9c13263
commit 4b77ef6823
1 changed files with 33 additions and 31 deletions
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64
src/cpu/386_common.c
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@@ -426,42 +426,44 @@ x386_common_log(const char *fmt, ...)
int
is_lock_legal(uint32_t fetchdat)
{
int legal;
fetch_dat_t fetch_dat;
int legal = 1;
fetch_dat.fd = fetchdat;
if (is386) {
fetch_dat_t fetch_dat;
fetch_dat.fd = fetchdat;
legal = lock_legal[fetch_dat.b[0]];
if (legal == 1)
legal = 1; // ((fetch_dat.b[1] >> 6) != 0x03); /* reg is illegal */
else if (legal == 2) {
legal = lock_legal_0f[fetch_dat.b[1]];
legal = lock_legal[fetch_dat.b[0]];
if (legal == 1)
legal = ((fetch_dat.b[2] >> 6) != 0x03); /* reg,reg is illegal */
else if (legal == 3) {
legal = lock_legal_ba[(fetch_dat.b[2] >> 3) & 0x07];
legal = 1; // ((fetch_dat.b[1] >> 6) != 0x03); /* reg is illegal */
else if (legal == 2) {
legal = lock_legal_0f[fetch_dat.b[1]];
if (legal == 1)
legal = ((fetch_dat.b[2] >> 6) != 0x03); /* reg,imm is illegal */
legal = ((fetch_dat.b[2] >> 6) != 0x03); /* reg,reg is illegal */
else if (legal == 3) {
legal = lock_legal_ba[(fetch_dat.b[2] >> 3) & 0x07];
if (legal == 1)
legal = ((fetch_dat.b[2] >> 6) != 0x03); /* reg,imm is illegal */
}
} else if (legal == 3) switch(fetch_dat.b[0]) {
case 0x80 ... 0x83:
legal = lock_legal_80[(fetch_dat.b[1] >> 3) & 0x07];
if (legal == 1)
legal = ((fetch_dat.b[1] >> 6) != 0x03); /* reg is illegal */
break;
case 0xf6 ... 0xf7:
legal = lock_legal_f6[(fetch_dat.b[1] >> 3) & 0x07];
if (legal == 1)
legal = ((fetch_dat.b[1] >> 6) != 0x03); /* reg is illegal */
break;
case 0xfe ... 0xff:
legal = lock_legal_fe[(fetch_dat.b[1] >> 3) & 0x07];
if (legal == 1)
legal = ((fetch_dat.b[1] >> 6) != 0x03); /* reg is illegal */
break;
default:
legal = 0;
break;
}
} else if (legal == 3) switch(fetch_dat.b[0]) {
case 0x80 ... 0x83:
legal = lock_legal_80[(fetch_dat.b[1] >> 3) & 0x07];
if (legal == 1)
legal = ((fetch_dat.b[1] >> 6) != 0x03); /* reg is illegal */
break;
case 0xf6 ... 0xf7:
legal = lock_legal_f6[(fetch_dat.b[1] >> 3) & 0x07];
if (legal == 1)
legal = ((fetch_dat.b[1] >> 6) != 0x03); /* reg is illegal */
break;
case 0xfe ... 0xff:
legal = lock_legal_fe[(fetch_dat.b[1] >> 3) & 0x07];
if (legal == 1)
legal = ((fetch_dat.b[1] >> 6) != 0x03); /* reg is illegal */
break;
default:
legal = 0;
break;
}
return legal;