[SOLVED] CS cache Q1 Locality 4 Points

Q1 Locality 4 Points
The following function sums up the elements in an array:
Q1.1
1 Point
What type of locality does the variable sum benefit from, assuming the code is highly optimized?
Spatial locality
Temporal locality
Both temporal and spatial locality
None, as sum will be put in register %rax instead of in memory.
Q1.2
1 Point

The loop needs to read an element of array a in each iteration. What type of locality can that array access benefit from?
Temporal locality
Spatial locality
Both temporal and spatial locality None
Q1.3
1 Point
If we change the loop body from
sum += a[i][j];
into
if(j>0) {sum += a[i][j] a[i][j-1]};
What type of locality can that array access to a[i][j-1] benefit from? Temporal locality
Spatial locality
Both temporal and spatial locality
None
Q1.4
1 Point
Program execution uses memory accesses to fetch not only data but also code from physical memory. For example, near the end of the execution of sumA , the program needs to fetch the ret instruction from memory. What type of locality can that memory access benefit from during the first execution of sumA?

Temporal locality
Spatial locality
Both temporal and spatial locality None
Q2 Caches 4 Points
You are given the a direct mapping cache (i.e., each set only contains one cache line block). Each cache line block is 64-Byte long; the whole cache capacity is 2048 Bytes; every memory address on this machine contains 32 bits.
Q2.1
1 Point
How many sets (S) does this cache have?
2 8 32 64 128
Q2.2
1 Point
While accessing the cache, how many bits in each memory address are used to locate the set?

2 3 4 5 6
Q2.3
1 Point
How many tag bits (t) does this cache use?
21 24 26 27
Q2.4
1 Point
Right after an access to memory location 0XAB3F, accessing which memory location below is guaranteed to get a cache hit?
0xAB08 0xAA3F 0xAC3F 0xAB40