FACULTY OF INFORMATICS

Code No. 2162 / O

B.E. 3/4 (IT) II-Semester (Old) Examination, May 2013

Time : 3 Hours

Subject : Compiler Construction (Elective – I)

Max. Marks: 75

Note: Answer all questions of Part - A and answer any five questions from Part-B. PART – A (25 Marks) 1. List the major data structures used in a compiler. 2. What is the purpose of a Literal table in a compiler? 3. Define left recursion removal, remove left recursion from. exp  exp + term / exp – term / term 4. Write LR(0) items for the following grammar E E + n / n 5. Define shift – reduce conflict and Reduce – reduce conflict. 6. Writ the Attribute grammar from number  number / digit digit  O / I 7. What is a basic block? How is it recognized? 8. What is meant by dead code? 9. What is Back-patching? 10. Write the functions of bootstrap loader.

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PART – B (5x10=50 Marks) 11. Convert the following Regular expression into an NFA (10 + 11) 0*1

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12. Compute the FIRST and FOLLOW sets for the following grammar Statement  if –stmt / other if –stmt  if (exp) statement else-part else-part  else statement /  exp  O / I

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13. Construct a DFA of LR (1) items for the following grammar S  id / V : = E V  id EV/n

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14.(a) Explain various parameters passing mechanisms. (b) Explain stack based runtime environment.

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15.(a) Explain code generation for control statements and Logic Expressions. (b) Write three Address code and P-code for the following Function Definition : int f (int x, int y) { return x + y + 1} Function call : f(2 + 3, 4)

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16.(a) Discuss about code optimization techniques. (b) Explain symbol table organization.

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17. Write short notes on the following: (a) Recursive Descent Parsing (b) Error Recovery in Bottom up parsers (c) Generating codes from DAGs

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