Lecture 13 Slides - Suraj @ LUMS

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Java with GenericsCo-routinesimport java.util.Hashtable;class Test {public static void main(String[] args) {Hashtable h =new Hashtable();h.put(new Integer(0), "value");String s = h.get(new Integer(0));System.out.println(s);CoroutinesChapter 10 Topics• The General Semantics of Calls and Returns• Implementing “Simple” Subprograms• Implementing Subprograms with Stack-DynamicLocal Variables• Nested Subprograms• Blocks• Implementing Dynamic Scoping2
The General Semantics of Callsand Returns• Def: The subprogram call and returnoperations of a language are together calledits subprogram linkageImplementing “Simple”Subprograms• Call Semantics:1. Save the execution status of the caller2. Carry out the parameter-passing process3. Pass the return address to the callee4. Transfer control to the calleeImplementing “Simple”Subprograms• Return Semantics:1. If pass-by-value-result parameters are used,move the current values of those parameters totheir corresponding actual parameters2. If it is a function, move the functional value toa place the caller can get it3. Restore the execution status of the caller4. Transfer control back to the callerImplementing “Simple”Subprograms• Required Storage: Status information of thecaller, parameters, return address, andfunctional value (if it is a function)• The format, or layout, of the noncode partof an executing subprogram is called anactivation record• An activation record instance is a concreteexample of an activation record (thecollection of data for a particularsubprogram activation)3
Page 1: procedure C; begin end;Pascal Code
Page 5: Implementing Subprograms withStack-

Lecture 13 Slides - Suraj @ LUMS

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