Unit Wise Assignments


Unit Wise Assignments 

Unit I

1)Explain  LEX features and specification.
2)Write regular expression for comment,operators,datatype,identifier ,keywords.

Unit II

1) Expalin automatic construction of parsers using YACC. (Explain for calculator with lex and yacc specifications)
2) Explain Need of semantic analysis.

Unit III

1)Explain with exampleThree-Address codes: Quadruples, Triples and Indirect Triples
2)Explain S and L attributed grammar


Unit iv

1)Explain Activation Record,
2)Explain display mechanism

Unit V

1)Explain Issues in code generation.
2)Explain Register allocation and Assignment,


Unit VI

1) Explain common sub-expression elimination, variable propagation, code movement, strength reduction, dead code elimination.
2)Explain Data flow equations and iterative data flow analysis.


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