Assignment Questions of System Software Subject (10CS52)

1.      Explain with example machine-independent assembler features.

2.      What are Literals,Symbvol-defining statements,

3.      Explain the Expressions and Program blocks.

4.      Brielfy explain One-pass Assemblers

5.      Explain  multi-pass assemblers.

6.      What is meant by machine independent assembler features?
The assembler features that does not depends upon the machine architecture are known as
machine independent assembler features.
Eg: program blocks,Literals.

7.      How the register to register instructions are translated in assembler?
In the case of register to register instructions the operand field contains the register name.During
the translation first the object code is converted into its corresponding machine language equivalent with
the help of OPTAB.Then the SYMTAB is searched for the numeric equivalent of register and that value
is inserted into the operand field.
Eg: 125 1036 RDREC CLEAR X B410
B4-macine equivalent of the opcode CLEAR
10-numeric equivalent of the register X.

1. Define macro processor.
2. What do macro expansion statements mean?
3. What are the directives used in macro definition?
4. What are the data structures used in macro processor?
5. Define conditional macro expansion.
6. What are the statements used for conditional macro expansion?
7. Consider the macro definition
   #Define DISPLAY(EXPR) Printf(“EXPR = %d\n”,EXPR)
   Expand the macro instruction DISPLAY (ANS)
8. How the macro is processed using two passes?
9. Mention the tasks involved in macro expansion.
10. How to design the pass structure of a macro assembler?