SRM INSTITUTE OF SCIENCE AND TECHNOLOGY

Ramapuram Campus, Bharathi Salai, Ramapuram, Chennai - 600089

FACULTY OF ENGINEERING AND TECHNOLOGY

DEPARTMENT OF COMPUTER SCIENCE

AND ENGINEERING

QUESTION BANK

DEGREE / BRANCH: B.TECH-CSE & CSE WITH SPECIALIZATION

VI SEMESTER

18CSC304JT – COMPILER DESIGN

2018 Regulation

Academic Year 2022-2023 EVEN SEMESTER

 SRM INSTITUTE OF SCIENCE AND TECHNOLOGY
Ramapuram Campus, Bharathi Salai, Ramapuram, Chennai-600089

DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING

QUESTION BANK

SUBJECT : 18CSC304J – COMPILER DESIGN

SEM/ YEAR: III/V

Course Outcomes

CO-1 : Acquire the knowledge of mathematics and engineering principles for the Design of Compilers
CO-2 : Acquire the ability to identify specification of a language's lexical rules of Lexical Analyzer
CO-3 : Apply the knowledge of Syntax Analyzer for parsing the sentences in a compiler grammar
CO-4 : Understand the concepts of translation of various intermediate codes .
CO-5 : Apply the knowledge to implement Code Generator for compilers
CO-6 : Analyze and Design the methods of developing a Code Optimizer

UNIT I
Compilers – Analysis of the source program-Phases of a compiler – Cousins of the Compiler-Grouping of Phases –
Compiler construction tools- Lexical Analysis – Role of Lexical Analyzer-Input Buffering- Specification of
Tokens--Finite automation – deterministic Finite automation - non deterministic-Transition Tables- Acceptance of
Input Strings by Automata-State Diagrams and Regular Expressions- Conversion of regular expression to NFA -
Thompson’s method-Conversion of NFA to DFA- Simulation of an NFA-Converting Regular expression directly to
DFA- Minimization of DFA-Minimization of NFA- Design of lexical analysis (LEX)
PART-A (Multiple Choice Questions)
Q. Questions Course Competence
Outcome BT Level
No
1 A Compiler is
a)A program that place program into memory and prepares them for execution
b)A program that automates the translation of assembly language into machine
language
c)A program that accepts program written in high level language and CO1 BT 1
produces an object program
d)A program that appears to execute a source program as if it were machine
language

2 Compiler can check ________ error.

a) Logical
b) Syntax CO1 BT 1
c) Content
d) Both A and B

3 Grammar is checked by which component of compiler

a) Scanner
b) Parser CO1 BT 1
c) Semantic Analyzer
d) None of the mentioned
 4 In a compiler, the data structure responsible for the management of
information about variables and their attributes is

a) Semantic stack
CO1 BT 1
b) Parser table
c) Symbol table
d)Syntax tree

5 How many tokens are there in following statement

?Printf(“j=%d,&j=%x”,j&j)
a)4
b) 5 CO2 BT 1
c) 9
d) 10

6 When is the type checking usually done?

a)Syntax directed translation
b)lexical analysis CO1 BT 1
c)code optimization
d) syntax analysis

7 How many DFA’s exits with two states over input alphabet {0,1} ?
a) 16
b) 26
CO2 BT 2
c) 32
d) 64

8 Regular expression for all strings starts with ab and ends with bba is.
a) aba*b*bba
b) ab(ab)*bba
CO2 BT 1
c) ab(a+b)*bba
d) All of the mentioned

9 Transition function maps.

a) Σ * Q -> Σ
b) Q * Q -> Σ CO1 BT 2
c) Σ * Σ -> Q
d) Q * Σ -> Q

10 Given an arbitrary non-deterministic finite automaton (NFA) with N states,

the maximum number of states in an equivalent minimized DFA is at least.

a) N^2
CO2 BT 2
b) 2^N
c) 2N
d) N!

11 In a compiler, keywords of a language are recognized during

a)parsing of the program
b)the code generation
CO1 BT 2
c)the lexical analysis of the program
d)dataflow analysis

12 Compiler should report the presence of __________ in the source program, in

translation process.
a) Classes
CO2 BT 1
b) Objects
c) Errors
d) Text
13 What is the output of lexical analyzer?
a) A parse tree
b) A list of tokens
CO2 BT 1
c) Intermediate code
d) Machine code

14 An NFA’s transition function returns

a) A Boolean value
b) A state
CO2 BT 2
c) A set of states
d) An edge

15 Which of the following is used for grouping of characters into tokens (in a
computer)
a)A parser
b) Code optimizer CO2 BT 1
c) Code generator
d)Scanner

16 Evaluate the number of states require to accept string ends with 10.
a) 3
b) 2 CO1 BT 2
c) 1
d) can’t be represented.
17 Which of the following is application of finite automata?
a)Compiler design
b)Grammar Parsers
CO2 BT 1
c)Text Search
d) All the above

18 Which of the following are language processor?

a) Assembler
b) Compiler CO1 BT 1
c) Interpreter
d) All the above

19 In regular expressions, the operator ‘*’ stands for?

a) Concatenation
b) Selection’ CO2 BT 1
c) Iteration
d) Addition

20 What is the relation between NFA accepted languages and DFA accepted
languages?

a) >
CO2 BT 1
b) <
c) =
d) <=

PART B (4 Marks)
1 Interpret the functions of lexical analyzer? CO2 BT 2
2 List the phases that constitute the front end of a compiler CO1 BT 1
3 What is a symbol table? CO1 BT 1
4 Justify, how will you group the phases of compiler? CO1 BT 1
5 Compare and Contrast between compiler and interpreter? CO1 BT 2
6 Manipulate the transition diagram for an identifier. CO1 BT 1
7 Summarize the algebraic properties of regular expressions? CO1 BT 1
8 Compare the features of DFA and NFA. CO2 BT 2
9 What is a finite automaton? CO2 BT 2
10 Classify the possible error recovery actions in lexical analyzer? CO2 BT 2
11 What are the issues of the lexical analyzer? CO2 BT 2
12 Indicate the role of lexical analyzer? CO2 BT 2
13 Write short notes on input buffering. CO1 BT 2
14 Mention the back-end phases of a compiler CO1 BT 2
15 Order the functions performed in analysis phase? CO1 BT 2
16 Order the functions performed in synthesis phase? CO1 BT 2
17 What are the factors affecting number of passes in compiler? CO1 BT 2
18 What are compiler construction tools? CO1 BT 2
19 Mention few cousins of compiler CO1 BT 2
20 Define token, pattern and lexeme. CO2 BT 1

PART C (12 Marks)

1 Define Compiler & List out its Phases. CO 1 BT 1
2 i) Discuss the role of lexical analyzer in detail.
CO 1 BT 1
ii) Explain briefly the design of lexical analyzer
3 Give the minimized DFA for the following expression. (a/b)*abb using direct
CO 2 BT 3
method
4 i) Explain the compiler construction tools
CO 1 BT 2
ii) Explain specification and recognition of tokens
5 Give the minimized DFA for the following expression

CO 2 BT 3

6 Explain input buffering in detail and Write briefly on the issues in input buffering
CO 2 BT 2
and how they are handled
7 Give the minimized DFA for the following expression. (a/b)*abb using tabulation
CO 2 BT 3
method
8 Prove the following two regular expressions are equivalent by showing the
minimum state DFA’s are same. CO 2 BT 3
i) (a/b)* ii) (a*/b*)
9 Explain the design of lexical analyzer using LEX CO 2 BT 2
Note:

1. BT Level – Blooms Taxonomy Level

2. CO – Course Outcomes

BT1 – Remember BT2 – Understand BT3 – Apply BT4 – Analyze BT5 – Evaluate BT6 – Create