Reg. No.
B.E. B.Tech. DEGREE EXAMINATION, MAY 2017
Sixth Semester
Computer Science and Engineering
01UCS601 PRINCIPLES OF COMPILER DESIGN
(Regulation 2013)
Duration: Three hours Maximum: 100 Marks
Answer ALL Questions
PART A (10 x 2 20 Marks)
1. Define Lexemes, Tokens, and Patterns.
2. Distinguish between compiler and interpreter.
3. Differentiate between final states in a NFA and a DFA.
4. What is the use of an error handler?
5. Write a brief note on YACC.
6. Write the drawbacks of shift-reduce parser.
7. Illustrate why every S-attributed definition is L-attributed.
8. What is annotated parse tree?
9. List the applications of DAG.
10. What is peephole optimization?
PART B x 16 80 Marks)
11. With a neat sketch, discuss the phases of a compiler.
Or
Question Paper Code: 31261
2
31261
What are the phases of compiler? Explain with a neat diagram. Also write down the output for the following expression after each phase c*d/e.
12. Construct an NFA to recognize the regular expression b a Obtain its equivalent DFA and minimize the number of states in DFA.
How is finite automata useful for lexical analysis?
Or
Design a Lexical analyzer generator. Also write the sample code which includes declaration, translation rules and auxiliary procedures.
13. Consider the following context free grammar G where P is
S Aa/ bAc/ dc/ bda
A d.
Show that this grammar is LALR but not SLR
Or
Consider the following grammar and construct a SLR parsing table for the same
E+T




14. Write the syntax directed definition for generating 3-address code for an assignment statement.
Or
With supporting examples, describe the run time storage management.
15. Elaborate the issues involved in design of a code generator.
Explain looping and flow graphs.
Or
Explain the code optimization techniques using examples.