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CPUT4 T&M: max indirect levels is 8 then RXM fault occurs (S/R mode)

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Jim 2011-08-06 14:44:42 -04:00
parent adbf7dff22
commit 499d07d82e
1 changed files with 16 additions and 2 deletions
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18
em.c
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@ -391,6 +391,10 @@ typedef struct {
char valid; /* 1 if IOTLB entry is valid, zero otherwise */
} iotlbe_t;
/* maximum indirect levels is 8 according to T&M CPUT4 */
#define INDLEVELS 8
/* the emulator uses a special, very small address translation cache
to hold the virtual page address and corresponding MEM[] pointer
for a few special pages:
@ -2078,6 +2082,7 @@ static void fault(unsigned short fvec, unsigned short fcode, ea_t faddr) {
static ea_t ea16s (unsigned short inst) {
unsigned short rpl, amask, i, x;
int indlevel;
ea_t ea, va;
i = inst & 0100000; /* indirect */
@ -2088,11 +2093,14 @@ static ea_t ea16s (unsigned short inst) {
ea = (rpl & 037000) | (inst & 0777); /* current sector */
else
ea = (inst & 0777); /* sector 0 */
indlevel = 0;
while (1) {
if (x) /* indexed */
ea += crs[X];
if (!i) /* not indirect */
break;
if (indlevel++ == INDLEVELS)
fault(RESTRICTFAULT, 0, 0);
ea &= amask;
if (ea < gvp->livereglim) /* flag live register ea */
ea |= 0x80000000;
@ -2113,6 +2121,7 @@ static ea_t ea16s (unsigned short inst) {
static ea_t ea32s (unsigned short inst) {
unsigned short rpl, amask, i, x;
int indlevel;
ea_t ea, va;
i = inst & 0100000; /* indirect */
@ -2128,7 +2137,9 @@ static ea_t ea32s (unsigned short inst) {
x = 0;
}
}
while (i) {
for (indlevel=0; i; indlevel++) {
if (indlevel == INDLEVELS)
fault(RESTRICTFAULT, 0, 0);
ea &= amask;
if (ea < gvp->livereglim) /* flag live register ea */
ea |= 0x80000000;
@ -2151,6 +2162,7 @@ static ea_t ea32s (unsigned short inst) {
static inline ea_t ea32r64r (ea_t earp, unsigned short inst) {
unsigned short ea, m, rph, rpl, amask, class, i, x;
int indlevel;
ea_t va;
x = ((inst & 036000) != 032000) ? (inst & 040000) : 0;
@ -2181,7 +2193,9 @@ static inline ea_t ea32r64r (ea_t earp, unsigned short inst) {
}
}
ea &= amask;
while (i) {
for (indlevel=0; i; indlevel++) {
if (indlevel == INDLEVELS)
fault(RESTRICTFAULT, 0, 0);
if (ea >= gvp->livereglim)
m = get16(MAKEVA(rph,ea));
else