CS606 Final Term Solved MCQs by Junaid

1. convert the relocatable machine code into absolute machine code by linking library and relocatable object files.

•  Assembler

 Loader/link-editor

•  Compiler
•  Preprocessor

2. Parsers take as input from lexical analyzer.

•  Linker

 Token

•  Instruction

3. The regular expression denotes, the set of all strings of a’s and b’s of length two

•  a*
•  (a*|b*)*
•  (a*b*)*

 (a|b)(a|b)

4. is a regular expression for the set of all strings over the alphabet {a} that has an even number of a’s.

•  aa*
•  (aa)*
•  aa*a
•  a(aa)*

5. Phase supports macro substitution and conditional compilation.

•  Semantic
•  Syntax

 Preprocessing

•  None of given

6. In LL(1) parsing algorithm, contains a sequence of grammar symbols.

 Stack

PG # 62

•  Link List
•  Array

7. Consider the grammar A  B C D B  h B | € C  C g | g | C h | i D AB | £ First of A is

 h, g, i

•  g
•  h

8. parsers never shifts into an error state.

•  LS
•  LT
•  LR
•  LP

9. In parser, the two LL stand for

•  Left-to-right scan of input
•  left-most derivation

 Left-to-right scan of input and left-most derivation PG # 54

10. is elaborated to produce bindings.

 Declaration

•  Expression
•  Command

11. A lexical analyzer generated by is essentially a FSA.

•  Dex
•  Mex
•  Fex
•  Lex

12. A lexical analyzer generated by lex is essentially a PDA (Push Down Automaton).

•  True

 False

13. T he actions (shift, reduce) in a SLR(1) parser depend on a look ahead symbol (

 Current input token

•  Next Input Token
•  Previous output Token
•  Previous Input Token.

14. The following grammar contains a conflict. S → A | xb

•  First-Reduce
•  Shift-First

15. S  A | xb A  aAb | x This grammar contains a conflict.

•  First-Reduce
•  Shift-First

16. Consider the Following S → AB

•  1
•  2
•  3
•  4

17. is a register allocation technique that always finds the minimal number of registers needed for a procedure.

•  Dangling reference

 Graph coloring

•  Left Factoring
•  Right Recursion

18. Graph coloring is a register allocation technique that operates at individual basic blocks.

•  True

 False

19. Graph coloring is a register allocation heuristic that usually