StudyNp | CSIT Sixth Semester – 2078 Question for Compiler Design and Construction

Tribhuwan University

2078

Bachelor Level / Third Year / Sixth Semester / Science

(Compiler Design and Construction)

Full Marks: 60

Pass Marks: 24

Time: 3 Hours

Candidates are required to give their answers in their own words as for as practicable.

The figures in the margin indicate full marks.

Long Answers Questions

List out the tasks performed by Lexical Analyser. Define DFA. Convert the Regular Expression $(a+b)^*a(a+b)$ to DFA directly.[10]

Differentiate between LR(0) and LR(1) algorithm. Construct LR(1) parse table of the following grammar.

$S \rightarrow AA$

$A \rightarrow aA | b$

[10]

Define type checking. Differentiate between type casting and coercion? Write SDT to carry out type checking for the following expression.

$E \rightarrow n \mid E * E \mid E == E \mid E[E] \mid E \uparrow$

[10]

Short Answers Questions

Define compiler and differentiate it with an interpreter. [5]

What are the typical entries made in symbol table? Explain. [5]

Define Left recursive grammar. Remove left recursion from the following grammar.

$S \rightarrow SB | Ca$

$B \rightarrow Bb | c$

$C \rightarrow aB | a$

[5]

What are the disadvantages of shift reduce parsing. Perform shift reduce parsing of string w = (x-x). (x/x) for given grammar.

$E \rightarrow E-E | E/E | (E) | x$

[5]

Define attribute grammar with example of inherited and synthesized attributes. [5]

Define three address codes. Write down Quadruples for:

$a = -b*(c+d)/e$

[5]

10.

List out different types of run time storage management techniques. Explain any one of them. [5]

11.

What is the advantages of code optimization? Explain about dead-code elimination. [5]

12.

Explain about the factors affecting target code generation. [5]