1. What is the main goal of code optimization?
A) To make the code more readable
B) To improve the performance of the code
C) To reduce the size of the source code
D) To make the code easier to debug
Answer: B) To improve the performance of the code
2. Which of the following is a common technique used in code optimization?
A) Removing comments from the code
B) Removing redundant instructions
C) Increasing the number of variables
D) Increasing the complexity of the code
Answer: B) Removing redundant instructions
3. Which type of optimization focuses on reducing the number of instructions executed by the program?
A) Loop optimization
B) Space optimization
C) Time optimization
D) Code reorganization
Answer: C) Time optimization
4. What is loop unrolling?
A) Increasing the number of loops in the code
B) Breaking a loop into multiple smaller loops to improve efficiency
C) Rewriting loops in an unordered sequence
D) Removing loops from the code entirely
Answer: B) Breaking a loop into multiple smaller loops to improve efficiency
5. Which of the following can result in improved performance by reducing the number of conditional branches in a program?
A) Loop invariant code motion
B) Branch prediction
C) Register allocation
D) Function inlining
Answer: B) Branch prediction
6. What is dead code elimination?
A) Removing code that has no effect on the program’s output
B) Deleting unused variables
C) Reducing the program’s execution time
D) Simplifying loops
Answer: A) Removing code that has no effect on the program’s output
7. What is constant folding in code optimization?
A) Replacing variables with constant values
B) Rewriting expressions with constant values to their evaluated result
C) Using loops to evaluate constants
D) Removing all constants from the code
Answer: B) Rewriting expressions with constant values to their evaluated result
8. Which of the following is an example of space optimization?
A) Removing unused variables from the code
B) Rewriting functions for better readability
C) Merging functions to reduce code size
D) Using fewer registers in the program
Answer: A) Removing unused variables from the code
9. In code optimization, what does function inlining do?
A) It replaces a function call with the function’s actual code to save time
B) It removes function definitions to make the code shorter
C) It increases the number of function calls in the program
D) It replaces all loops with function calls
Answer: A) It replaces a function call with the function’s actual code to save time
10. What is the impact of instruction scheduling in code optimization?
A) It reduces the number of instructions in the program
B) It changes the order of instructions to minimize delays due to hazards
C) It increases the program’s space requirements
D) It automatically parallelizes the code
Answer: B) It changes the order of instructions to minimize delays due to hazards
11. What is the purpose of register allocation in code optimization?
A) To minimize the number of registers used
B) To store variables in memory instead of registers
C) To increase the number of available registers
D) To improve the speed of memory access
Answer: A) To minimize the number of registers used
12. Which of the following optimization techniques is focused on reducing the memory usage of the program?
A) Loop unrolling
B) Instruction selection
C) Space optimization
D) Constant propagation
Answer: C) Space optimization
13. Which technique eliminates unnecessary loads and stores in a program during optimization?
A) Copy propagation
B) Instruction scheduling
C) Dead code elimination
D) Constant folding
Answer: A) Copy propagation
14. What is the role of alias analysis in code optimization?
A) To predict memory addresses and optimize pointer usage
B) To detect redundant function calls
C) To remove dead variables
D) To reorder instructions
Answer: A) To predict memory addresses and optimize pointer usage
15. What is peephole optimization?
A) A low-level optimization technique that improves efficiency by examining a small window of code at a time
B) A technique that optimizes entire loops
C) A method to rewrite functions for better performance
D) A technique that rewrites high-level code into machine-level code
Answer: A) A low-level optimization technique that improves efficiency by examining a small window of code at a time
16. What is a primary disadvantage of aggressive optimization?
A) It leads to increased code size
B) It can make the code harder to debug and maintain
C) It guarantees faster execution
D) It improves readability
Answer: B) It can make the code harder to debug and maintain
17. Which of the following statements is true regarding the tradeoff in code optimization?
A) Optimizing for time always results in better space performance
B) Optimization for space may increase execution time
C) Code optimization guarantees reduced program size and improved execution time
D) Optimization always improves code readability
Answer: B) Optimization for space may increase execution time
18. Which optimization technique is primarily used to eliminate redundant calculations in loops?
A) Loop fusion
B) Loop unrolling
C) Loop invariant code motion
D) Instruction scheduling
Answer: C) Loop invariant code motion
19. What is loop fusion?
A) Combining multiple loops into a single loop for better performance
B) Unrolling loops to improve execution time
C) Removing loops to decrease program size
D) Reversing loops for better memory access
Answer: A) Combining multiple loops into a single loop for better performance
20. Which of the following is an example of compiler optimization?
A) Syntax checking
B) Generating intermediate code
C) Optimizing the generated machine code for faster execution
D) Checking for logical errors in the code
Answer: C) Optimizing the generated machine code for faster execution