Computer Science 2500 Computer Organization Rensselaer Polytechnic Institute Spring 2009

Agenda

• Announcements
  • Office hours back to normal this week
  • Schedule changes - new exam date
• Lab 1 Recap
• Lab 2 Continues
  • ask questions!
  • there were mistakes in my solution in the shamt and immedoffset fields, fixed now
  • memory is just a bunch of bits, no matter how those bits got there or how you use them later
  • brief discussion of memory management in itemparser example
  • brief discussion about Makefiles
• MIPS Programming
  • control structures
  • byte-sized memory accesses
  • string processing example
  • subroutines and programs
  • registers and the stack
  • a recursive subroutine

Lecture Assignment

Due at the start of class, Friday, February 6.

Recall the class example "shiftyproduct" that includes the following code snip:

  product = 0;
  while (y) {
    if (y&1) product += x;
    y >>= 1;
    x <<= 1;
  }

Suppose the variables x, y, and product are stored in registers $s0, $s1, $s2, respectively. Write clear and concise MIPS assembly code for the C code above.

Turn in a hard copy (handwritten or typeset). We will go over this at the start of class, so no late submissions are accepted.