Unit Test questions

Unit I

1)Explain Role of Lexical Analyzer in Compiler
2)  Explain use of yyleng, yytext, yylval, yywrap in yacc..

Unit II

1)Construct LR(0) item-set for following grammar.
E E + E | E * E | id where + , * , id are terminals.
2) Explain left factoring with example.

Unit III


1)Generate Quadruple for a = b + (c * d) / f
2) Explain  Intermediate code generation of declaration statement.

Unit IV

1)Explain Parameter passing methods along with suitable example [8]
b) Explain Function Call and Return with suitable example


Unit V

1)Explain Simple Code Generator Algorithms along with suitable
example. [8]
2) What is DAG? Explain the role of DAG in Code Generation


Unit VI

1)What is loop transformations? What are its types
2)Explain Following Data Flow Properties
Available Expressions, Reaching Definitions

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