1. Discuss S-attributed and L-attributed SDD.

2. (06 Marks) (Dec.2019/Jan.2020)

3. Write 3-address code syntax tree and DAG for the expression a + a * (b-c) +(b-c) *d (10 Marks) (Dec.2019/Jan.2020)

4. Obtain the SDD and construct annotated parse tree for the input string 6 * 5 + 3, for the grammar

S -> EN

E -> E+T/T

T -> T*F/F

F -> (E)digit

N ->;

(10 Marks) (Dec.2019/Jan.2020)

5. Discuss the issues in n the design of code generator. (06 Marks) (Dec.2019/Jan.2020)

6. Consider the context free grammer given below

S -> EN

E -> E+T|E-T|T

T -> T*F|T/F|F

F -> (E) | digit

N -> ;

i. Obtain the SDD for the above grammer

ii. Construct annotated parse tree for the input string 5 * 6+ 7. (08 Marks) (June/July 2019)

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7. Obtain the DAG for the expression, show the steps a+ a *(b - c) +(b - c) * d.(04 Marks) (June/July 2019)

8. Translate the assignment a-b* -c +b* -c into

i. Three address code

ii. Quadruples. (04 Marks) (June/July 2019)

9. Explain the issues in the design of a code generator. (11 Marks) (June/July 2019)

10. Write the machine instructions for the following three address instructions:

i. b=a[i]

ii. a[j]=e

iii. x =*p

iv. *p = y

v. if x <y got L. (05 Marks) (June/July 2019)

11. Define synthesized and inherited attributes with examples. (04 Marks) (Dec.2018/Jan.2019)

12. Briefly explain the main issues in code generations. (08 Marks) (Dec.2018/Jan.2019)

13. Explain in brief dead code elimination.(04 Marks) (Dec.2018/Jan.2019)

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14. Construct DAG for the expression.

a+b*(a+b)+c+d (04 Marks) (Dec.2018/Jan.2019)

15. Give SDD of a simple calculator (04 Marks) (Dec.2018/Jan.2019)

16. Write a note on common sub expression (04 Marks) (Dec.2018/Jan.2019)

17. What are the steps involved in optimization of basic blocks. Explain any 2 steps in brief (04 Marks) (Dec.2018/Jan.2019)

18. Discuss S-attributes and L-attributes with respect to SDD (Syntax Directed Definition). (04 Marks) (June/July 2018)

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19. Construct the syntax tree for the expression x * y-5 +z. (04 Marks) (June/July 2018)

20. Explain the translation of expression address code of

i) Quadruples

ii) Triples

iii) Indirect triples, with examples. (08 Marks) (June/July 2018)

21. Briefly explain the main issues in code generation. (08 Marks) (June/July 2018)

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22. Generate code for the following expression using the code generator algorithm.

X: =(a+b) * (c - d). (08 Marks) (June/July 2018)