/*
** Write_Cache - this writes a word to the cache, and also writes
** the value out to memory.
*/
void Write_Cache(unsigned long int address, unsigned long int data){
int i;
unsigned long int word;
unsigned long int tag;
unsigned long int set;
unsigned long int cache_line;
tag = address & TAG_MASK;
word = address & WORD_MASK;
set = address & SET_MASK;
cache_line = set >> SET_SHIFT;
if( (tags[cache_line] == tag) && (IS_VALID(cache_line)) ){
cache_hits++;
LRU_Access(cache_line);
rammem[set + tag + word] = cache[cache_line][word] = data;
}
else {
cache_misses++;
for(i = 0; i < NUM_WORDS_PER_LINE; i++){
cache[cache_line][i] = rammem[tag + set + i];
}
tags[cache_line] = tag;
LRU_Access(cache_line);
rammem[set + tag + word] = cache[cache_line][word] = data;
}
}
/*
** Write_Cache - this writes a word to the cache, and also writes
** the value out to memory.
*/
void Write_Cache(unsigned long int address, unsigned long int data){
int i,j;
int invalid_line = -1;
int victim = 0;
unsigned long int word;
unsigned long int block;
block = address & TAG_MASK;
word = address & WORD_MASK;
for(i = 0; i < NUM_CACHE_LINES; i++){
if( !IS_VALID(i) ){
invalid_line = i;
}
else{
if(block == tags[i])
break;
}
}
if(i == NUM_CACHE_LINES){
/* cache miss -- find a victim */
cache_misses++;
if(invalid_line != -1){
for(j = 0; j < NUM_WORDS_PER_LINE; j++){
cache[invalid_line][j] = rammem[block + j];
}
tags[invalid_line] = block;
LRU_Access(invalid_line);
rammem[block + word] = data;
cache[invalid_line][word] = data;
}
else{
for(j = 0; j < NUM_CACHE_LINES; j++){
if(mem_count[j] > mem_count[victim]){
victim = j;
}
}
for(j = 0; j < NUM_WORDS_PER_LINE; j++){
cache[victim][j] = rammem[block + j];
}
tags[victim] = block;
LRU_Access(victim);
rammem[block + word] = data;
cache[victim][word] = data;
}
}
else{
/* cache hit - just write the puppy out */
cache_hits++;
LRU_Access(i);
rammem[block + word] = data;
cache[i][word] = data;
}
}
