Main Ideas For Today

• Array/Structure/Reference Representation in Memory
• Immediate Label addressing mode
• Indirect addressing mode
• Allocating Arrays
• Creating References
• Accessing Array Elements
• Processing Arrays
• Accessing Structure Fields

Lecture Slides

• Class #10 - Arrays and References
  (Slides are only available for download from on-campus locations)

Homework Assigned Today

Due Date: 10/11/04


1. Write an assembly language equivalent for the following HLL code:
   int y[] = {7, 3, 9, 18, 4, 12, 22, 5, 1, 2, 6, 0, 14, 33, 8, 11}; int x[] = new int[15]; for (int i=0; i<15; i++) { x[i] = y[i+1]; }
   
   NOTES: Be sure to assemble and test your program using our assembler and machine emulator.
   
   
2. Consider the following class definition:
   public class Foo { public int y; public int z; }

   The figure to the right shows how an object of type Foo and several references to it might be organized in main memory. Assuming that the labels f, g, A and B exist, write assembly language instructions that perform the following operations: f.y = 17; f.z = 99; A = g.y; B = g.z; HINT:You'll need to use the immediate label and the indirect addressing modes.

   
   
   
3. Write an assembly language equivalent for the following HLL code:
   int x[] = new int[10]; int y[] = new int[10]; int a[]; int b[]; int q; q = <read from STDIN>; if (q > 0) { a = x; } else { a = y; } b = a;
   HINT: Think carefully about what this program would do in Java. You'll need to explicitly setup references for this one!