PSU TEE and/or HW 4?

Tom Kelliher, CS 220

Oct. 24, 1997

Announcements

1. Due to popular request, the deadline for homework 4 has been extended to Wednesday, Oct. 29.

2. I will be out of town Oct. 29--31.

Assignment

Nothing new.

Today's Material

1. First, I will handle questions on the assignment. Perhaps, it would be best to use the class time for lab time.

   This is how I solve these sorts of low-level programming problems. I find this methodology very useful:

   1. Solve the problem at a high level.

   2. Determine the key code fragments. In this case they were:
      1. Masking and testing an msb or lsb.

      2. 64-bit shift.

      3. 64-bit add.

      4. Binary input.

      5. Binary output.

   3. For each of the key fragments, I write individual SAL programs to try-out and debug my SAL code.

   4. Assemble and combine the pieces into the final program.

   This is much more time effective than writing a big, monolithic program and trying to debug it as a whole. It's much easier to debug it in these small pieces.

2. As time permits, we will continue with the PSU Trace Execution Engine (TEE).