int getFrame(int notme)
{
int UPTClock; // clock for UPT
int frame;
frame = getAvailableFrame();
if (frame >=0) return frame;
if(RPTClock == 0){
RPTClock = LC3_RPT;
}
int RPTBegin = RPTClock;
int first = 1;
int rptCount = 0;
//iterate the first time through the tables
while(first || RPTClock != RPTBegin){
rptCount++;
first = 0;
//Check and make sure the notme condition holds
if(DEFINED(memory[RPTClock])){
UPTClock = (FRAME(memory[RPTClock])<<6);
int UPTBegin = UPTClock;
int uFirst = 1;
int hadDefined = 0;
int uptcount = 0;
while(uFirst || UPTClock != UPTBegin){
uptcount++;
uFirst = 0;
if(DEFINED(memory[UPTClock])){
hadDefined = 1;
}
if(notme != UPTClock && DEFINED(memory[UPTClock])){
//swap out if not referenced
if(!REFERENCED(memory[UPTClock])){
//if it's dirty, write it to memory
int swapPage = 0;
if (DIRTY(memory[UPTClock])){
if(PAGED(memory[UPTClock + 1])) swapPage = accessPage(SWAPPAGE(memory[UPTClock + 1]), FRAME(memory[UPTClock]), PAGE_OLD_WRITE);
else swapPage = accessPage(0, FRAME(memory[UPTClock]), PAGE_NEW_WRITE);
memory[UPTClock] = CLEAR_DIRTY(memory[UPTClock]);
memory[UPTClock+1] = SET_PAGED(swapPage);
pageWrites++;
}
//no longer in main memory--it's swapped!
memory[UPTClock] = CLEAR_DEFINED(memory[UPTClock]);
//increment the clock
if(RPTClock + 2 < LC3_RPT_END)
RPTClock += 2;
else
RPTClock = LC3_RPT;
return FRAME(memory[UPTClock]);
}
memory[UPTClock] = CLEAR_REF(memory[UPTClock]);
}
//sanity check
assert(UPTClock >= 0x3000);
if(UPTClock + 2 < UPTBegin + LC3_FRAME_SIZE)
UPTClock += 2;
else
UPTClock = UPTBegin;
}
if(!REFERENCED(memory[RPTClock]) && !hadDefined && notme != RPTClock){
int swapPage;
if(PAGED(memory[RPTClock + 1])) swapPage = accessPage(SWAPPAGE(memory[RPTClock + 1]), FRAME(memory[RPTClock]), PAGE_OLD_WRITE);
else swapPage = accessPage(0, FRAME(memory[RPTClock]), PAGE_NEW_WRITE);
memory[RPTClock] = CLEAR_DIRTY(memory[RPTClock]);
memory[RPTClock+1] = SET_PAGED(swapPage);
pageWrites++;
memory[RPTClock] = CLEAR_DEFINED(memory[RPTClock]);
int rE1 = memory[RPTClock];
if(RPTClock + 2 < LC3_RPT_END)
RPTClock += 2;
else
RPTClock = LC3_RPT;
return FRAME(rE1);
}
//clear the reference bit
memory[RPTClock] = CLEAR_REF(memory[RPTClock]);
}
if(RPTClock + 2 < LC3_RPT_END){
RPTClock += 2;
}
else{
RPTClock = LC3_RPT;
}
}
RPTBegin = RPTClock;
first = 1;
while(first || RPTClock != RPTBegin){
rptCount++;
first = 0;
//Check and make sure the notme condition holds
if(DEFINED(memory[RPTClock])){
UPTClock = (FRAME(memory[RPTClock])<<6);
int UPTBegin = UPTClock;
int uFirst = 1;
int hadDefined = 0;
int uptcount = 0;
while(uFirst || UPTClock != UPTBegin){
uptcount++;
uFirst = 0;
if(DEFINED(memory[UPTClock])){
hadDefined = 1;
}
if(notme != UPTClock && DEFINED(memory[UPTClock])){
//swap out if not referenced
if(!REFERENCED(memory[UPTClock])){
//if it's dirty, write it to memory
int swapPage = 0;
if (DIRTY(memory[UPTClock])){
if(PAGED(memory[UPTClock + 1])) swapPage = accessPage(SWAPPAGE(memory[UPTClock + 1]), FRAME(memory[UPTClock]), PAGE_OLD_WRITE);
else swapPage = accessPage(0, FRAME(memory[UPTClock]), PAGE_NEW_WRITE);
memory[UPTClock] = CLEAR_DIRTY(memory[UPTClock]);
memory[UPTClock+1] = SET_PAGED(swapPage);
pageWrites++;
}
//no longer in main memory--it's swapped!
memory[UPTClock] = CLEAR_DEFINED(memory[UPTClock]);
//increment the clock
if(RPTClock + 2 < LC3_RPT_END)
RPTClock += 2;
else
RPTClock = LC3_RPT;
return FRAME(memory[UPTClock]);
}
memory[UPTClock] = CLEAR_REF(memory[UPTClock]);
}
//sanity check
assert(UPTClock >= 0x3000);
if(UPTClock + 2 < UPTBegin + LC3_FRAME_SIZE)
UPTClock += 2;
else
UPTClock = UPTBegin;
}
if(!REFERENCED(memory[RPTClock]) && !hadDefined && notme != RPTClock){
int swapPage;
if(PAGED(memory[RPTClock + 1])) swapPage = accessPage(SWAPPAGE(memory[RPTClock + 1]), FRAME(memory[RPTClock]), PAGE_OLD_WRITE);
else swapPage = accessPage(0, FRAME(memory[RPTClock]), PAGE_NEW_WRITE);
memory[RPTClock] = CLEAR_DIRTY(memory[RPTClock]);
memory[RPTClock+1] = SET_PAGED(swapPage);
pageWrites++;
memory[RPTClock] = CLEAR_DEFINED(memory[RPTClock]);
int rE1 = memory[RPTClock];
if(RPTClock + 2 < LC3_RPT_END)
RPTClock += 2;
else
RPTClock = LC3_RPT;
return FRAME(rE1);
}
//clear the reference bit
memory[RPTClock] = CLEAR_REF(memory[RPTClock]);
}
if(RPTClock + 2 < LC3_RPT_END){
RPTClock += 2;
}
else{
RPTClock = LC3_RPT;
}
}
//we should never ever be here
assert(0);
return -1;
}
unsigned short int *getMemAdr(int va, int rwFlg)
{
unsigned short int pa;
int rpta, rpte1, rpte2;
int upta, upte1, upte2;
int rptFrame, uptFrame;
extern TCB tcb[MAX_TASKS];
extern int curTask;
//stat
memAccess++;
rpta = tcb[curTask].RPT + RPTI(va); // 0x2400 + RPTI(va);
rpte1 = memory[rpta];
rpte2 = memory[rpta+1];
// turn off virtual addressing for system RAM
if (va < 0x3000) return &memory[va];
#if MMU_ENABLE
if (DEFINED(rpte1))
{
// defined
//stat
memHits++;
if (rwFlg)
rpte1 = SET_DIRTY(rpte1);
}
else
{
// fault
//stat
memPageFaults++;
rptFrame = getFrame(-1);
rpte1 = SET_DEFINED(rptFrame);
if (PAGED(rpte2))
{
accessPage(SWAPPAGE(rpte2), rptFrame, PAGE_READ);
//stat
pageReads++;
//clean
if (rwFlg)
rpte1 = SET_DIRTY(rpte1);
else
rpte1 = CLEAR_DIRTY(rpte1);
}
else
{
memset(&memory[(rptFrame<<6)], 0, 128);
//dirty
rpte1 = SET_DIRTY(rpte1);
}
}
rpte1 = SET_PINNED(rpte1);
memory[rpta] = rpte1 = SET_REF(rpte1);
memory[rpta+1] = rpte2;
upta = (FRAME(rpte1)<<6) + UPTI(va);
upte1 = memory[upta];
upte2 = memory[upta+1];
//stat
memAccess++;
if (DEFINED(upte1))
{
// defined
//stat
memHits++;
if (rwFlg)
upte1 = SET_DIRTY(upte1);
}
else
{
// fault
//stat
memPageFaults++;
uptFrame = getFrame(FRAME(memory[rpta]));
upte1 = SET_DEFINED(uptFrame);
if (PAGED(upte2))
{
accessPage(SWAPPAGE(upte2), uptFrame, PAGE_READ);
//stat
pageReads++;
//clean unless being written to
if (rwFlg)
upte1 = SET_DIRTY(upte1);
else
upte1 = CLEAR_DIRTY(upte1);
}
else
{
//dirty
upte1 = SET_DIRTY(upte1);
}
}
rpte1 = SET_PINNED(rpte1);
memory[rpta] = rpte1;
memory[upta] = upte1 = SET_REF(upte1);
memory[upta+1] = upte2;
return &memory[(FRAME(upte1)<<6) + FRAMEOFFSET(va)];
#else
return &memory[va];
#endif
} // end getMemAdr
