Compiler Design-Unit V MCQ

1. Peep-hole optimization is a form of

• loop optimization

• local optimization

• constant folding

• data flow analysis

An optimizing compiler

• is optimized to occupy less space

• is optimized to take less time for execution

• optimizes the code

• all the above

Substitution of values for names whose values are constant, is done in

• local optimization

• loop optimization

• constant folding

• none of these

Local and loop optimization in turn provide motivation for

• data flow analysis

• constant folding

• peep hole optimization

• DFA and constant folding

Some code optimizations are carried out on the intermediate code because

• they enhance the portability of the compiler to other target processors

• program analysis is more accurate on intermediate code than on machine code

• the information from dataflow analysis cannot otherwise be used for optimization

• the information from the front end cannot otherwise be used for optimization

The optimization which avoids test at every iteration is

• Loop unrolling

• Loop jamming

• Constant folding

• None of the mentioned

The graph that shows basic blocks and their successor relationship is called

• DAG

• Flow graph

• Control graph

• Hamilton graph

Which of the following is not a regular expression?

• [(a+b)*-(aa+bb)]*

• [(0+1)-(0b+a1)*(a+b)]*

• (01+11+10)*

• (1+2+0)*(1+2)*

With V (greater than 1) vertices, how many edges at most can a Directed Acyclic Graph possess?

• (V*(V-1))/2

• (V*(V+1))/2

• (V+1)C2

• (V-1)C2

The topological sorting of any DAG can be done in ________ time.

• cubic

• quadratic

• linear

• logarithmic