$1.$ Assume that a direct$-$mapped cache has:

$$ four $4-$byte cache blocks $($lines$)$;

$6-$bit memory addresses;

$$ write$-$back and write$-$allocate policy;

$$ memory$-$byte addressable; and

$$ big Endian byte$-$ordering schemes.

Assume that all accesses are to READ or WRITE a single byte. The initial conditions of the data

cache memory and a part of memory are:

i$.$ Cache memory $($initial condition$)$:

Index # Valid Dirty Tag Data $($in hex$)$

$001000$ A$1$ A$2$ A$3$ A$4$

$011001$ C$5$ C$6$ C$7$ C$8$

$101000$ B$1$ B$2$ B$3$ B$4$

$111001$ D$5$ D$6$ D$7$ D$8$

ii$.$ A part of Memory $($initial condition$)$:

Address Contents $($in hex$)$ Address Contents $($in hex$)$

$000000$ A$1$ A$2$ A$3$ A$4011000$ D$1$ D$2$ D$3$ D$4$

$000100$ A$5$ A$6$ A$7$ A$8011100$ D$5$ D$6$ D$7$ D$8$

$001000$ B$1$ B$2$ B$3$ B$4100000$ E$1$ E$2$ E$3$ E$4$

$001100$ B$5$ B$6$ B$7$ B$8100100$ E$5$ E$6$ E$7$ E$8$

$010000$ C$1$ C$2$ C$3$ C$4101000$ F$1$ F$2$ F$3$ F$4$

$010100$ C$5$ C$6$ C$7$ C$8101100$ F$5$ F$6$ F$7$ F$8$

iii. The processor of a load$/$store machine fetched and executes according to the following

sequence of memory addresses $($memory references, from $1$ to $6).$ Assume $11,22,$ and $33$

are hex values.

Order Memory reference Inst. Type Description

$1010001$ load

$2000101$ Load

$301000111$ Store Write $11$ to $010001$

$400010122$ Store Write $22$ to $000101$

$5100000$ Load

$610010033$ Store Write $33$ to $100100$

a$)$ Which of the memory references $($from $1$ to $6)$ will be misses? You can list the memory

references by using $1$ to $6.$

b$)$ After execution of memory references from $1$ to $6,$ show the updated contents of the cache

memory. You can answer the changes only but do show the entire cache line.

Index # Valid Dirty Tag Data $($in hex$)$

$00$

$01$

$10$

$11$

c$)$ Are there any updates in the contents of memory after execution of memory references from

$1$ to $6?$ If yes, show the updated memory contents. You can answer the changes only.

Address Contents $($in hex$)$ Address Contents $($in hex$)$

$000000011000$

$000100011100$

$001000100000$

$001100100100$

$010000101000$

$010100101100$