ARMv8-A Architecture

Question 1

is ARM a RISC or CISC machine

Answer 1

Advanced RISC Machine

Question 2

Does ARM use a von Neumann or Harvard architecture?

Answer 2

Von Neumann.(RAM contains both data and programs)

Question 3

What is the use of registers x0-x7?

Answer 3

Used to pass arguments into a procedure and return results

Question 4

Callee-saved registers

Answer 4

Registers where the value is preserved by any function call

Question 5

Purpose of the Stack Pointer

Answer 5

Used to point to the top of the runtime stack

Question 6

Purpose of the Program Counter

Answer 6

Holds the address of the currently executing instruction

Question 7

mov x29, sp is an alias for…

Answer 7

add x29, sp, 0

Question 8

mov Wd, Wn is an alias for…

Answer 8

orr Wd, wzr, Wn

Question 9

stp x29, x30

Answer 9

Stores the contents of the pair of registers to the stack

Question 10

mov x29, sp

Answer 10

Updates the FP to the current SP

Question 11

ldp x29, x30

Answer 11

Restores the state of the FP and LR registers

Question 12

Calculation of
madd x19, x20, x21, x22

Answer 12

x19 = x22+(x20 X x21)

Question 13

Z flag returns true when…

Answer 13

result is zero

Question 14

N flag returns true when…

Answer 14

result is negative

Question 15

V flag returns true when…

Answer 15

result overflows

Question 16

C flag returns true when…

Answer 16

Result generates a carry out

Question 17

What is EL0?

Answer 17

Exception level for normal user applications with limited priveleges

Question 18

What is EL1?

Answer 18

Exception level for the OS kernel. Accessed indirectly using system calls.

Question 19

What is EL2?

Answer 19

Exception level for a hypervisor. Supports virtualization.

Question 20

What is EL3?

Answer 20

Exception level for low level firmware. Includes the Secure Monitor