System Software 2001

Gujarat University

MCA Semester III

System Software

Date: 17^th January, 2001                                                                                                                              Marks:50

Instructions:

1.      Answers to the two sections should be written in separate answer books.

2.      Make necessary assumptions wherever necessary.

Section I

Q-1      Given the following program:                          [9]

                                    START            300

            ID1                  DS                   5

            L1                    MOVER         AREG, D

                                    ADD               AREG, C

                                    SUB                AREG, ID2

                                    MOVEM         AREG, ID1

            D                     EQU                ID2

            L2                    PRINT                        D

                                    ORIGIN         ID1-1

            C                     DC                  ‘9’

                                    ORIGIN         L2+1

                                    STOP 

            ID2                  DC                  ‘13’

                                    END                L1

            Show the contents of symbol table and intermediate code at the end of pass-i.

Q-2 a) Give general algorithm of bottom-up parsing. Also give the trace of the algorithm giving suitable examples.

       b) Compare and contrast recursive decent parsing with LL(1) parsing. What grammar forms are acceptable to each of these?                       [8]

OR

Q-2 a) Describe the architecture of the Intel 8088.             [8]

       b) Given the following macro definition :

                        MACRO

                                    CLEARMEN              &X, &N, &REG= AREG

                                    LCL                            &M

            &M                  SET                             0

                                    MOVER                     &REG, =’0’

            .MORE           MOVEM                     &REG, &X + &M

            &M                  SET                             &M +1

                                    AIF                             (&M NE N) . MORE

                                    MEND

            Show the contents of the data structures deployed by the macro-processor for the call.

            CLEARMEN              AREA, 10

Q-3      Write short notes on the following (any two):             [8]

a)      Language processor development tools

b)      Hash table organization

c)      Debugger

d)     Grammar for language specification

Section II

Q-4 a) Describe the structure of an MS-DOS device driver.            [9]

       b) What is the difference between character-device driver and block-device driver.

Q-5 a) Describe the compilation of the expression giving suitable examples.          [8]

       b) Compare and contrast the following parameter passing mechanisms in terms of execution efficiency and power to produce side effects:                                  

i)                    call by value result

ii)                  call by reference

iii)                call by name

OR

Q-5 a) What do you understand by code optimization? How can control and data flow analysis can help in global optimization.            [8]

       b) Explain the structure of the stack structured symbol table.               

Q-6 a) What are Translated origin, linked origin and Load origin? Explain. Explain the relocation and linking

requirements in segmented addressing.          [8]

OR

Q-6 a) Give general algorithm for linking.                 [8]

       b) Compare and contrast the following:

i)                    Absolute loaders

ii)                  Relocating loaders

iii)                Direct linking loaders