StudyNp | CSIT Sixth Semester – 2081.1 Question for Compiler Design and Construction

Tribhuwan University

2081.1

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

Discuss about Directed Acyclic Graph with an example. Represent the expression A = (B + C) - (D - E) using 3AC, Quadruple and Triple. [10]

Create the LR(1) parsing table for following grammar.

S \rightarrow AA

A \rightarrow 0A

A \rightarrow \varepsilon

[10]

Explain the optimization techniques for code optimization. Convert the following program to basic block and control flow.

M = A + B

N = C + D

\text{IF } (M > N) \rightarrow X = M - N;

\text{ELSE } E = M + N + X

[10]

Short Answers Questions

Compute the FIRST and FOLLOW of all the non-terminals in following grammar.

S \rightarrow AB

A \rightarrow 0A' \mid 1A' \mid \varepsilon

A' \rightarrow SSA' \mid \varepsilon

B \rightarrow AS \mid 1

[5]

What are the operations performed in symbol table? Discuss about activation tree. [5]

What are the roles of macros and preprocessor? Discuss about one pass and multi pass compiler. [5]

Define explicit and implicit type conversion. Why do we need to check type of the system? Justify with an example. [5]

Differentiate between synthesized and inherited attributes with example. [5]

Construct the LL(1) parsing table for the following grammar.

S \rightarrow AS1 \mid C

A \rightarrow 0

C \rightarrow 2C \mid \varepsilon

[5]

10.

What are the advantages of intermediate code? How do you convert procedure call to 3AC? [5]

11.

What is a symbol table? Discuss the general structure of an LR parser. [5]

12.

Generate the LR(0) item sets for the following grammar.

A \rightarrow BB

B \rightarrow bB \mid a

[5]