9.2 Structured Programming

Question 1

When running a program what items are stored in memory (segments of memory)

Answer 1

Question 2

What is the purpose of the stack

Answer 2

• Subroutine state and local variables

Question 3

What is a stack overflow and its implications

Answer 3

Stack expands and can overwrite program etc.

Note: Stack grows downwards

Question 4

What steps are required to implement subroutine calls using the stack

Answer 4

Question 5

In HEX-8, what instructions are used to implement subroutine calls using the stack

Answer 5

Question 6

What is the stack frame (subroutine)

Answer 6

Current ‘state’ frame of the subroutine. Params, return address, local variables etc.

Question 7

Do real computers use the stack for program counter and return addresses

Answer 7

Not usually. Most have special Stack Pointer and link registers.

Question 8

What is an exception

Answer 8

Question 9

How can the logic regarding subroutines on the stack be translated to dealing with exceptions

Answer 9

Branches to exception handlers similar to subroutine branches with return addresses.