Description
Purpose: Become familiar with the tool chain → the assembler, linker, and debugger. Also become
familiar with the operating system and a text editor (of your choice).
Points: 15
Assignment:
Learn to assemble, link, and utilize the debugger with a provided program.
● Create a working directory where the working files will be placed (Home Folder → right click
and select Create Folder). Note, you may opt to choose a cloud storage option, which will
mean using a different directory.
● Download the assignment #1 assembly language program from the class web site into the
working directory.
● Edit the provided file to include your name, assignment number, and section number. This
information should be included on all assignments. Note, if you wish to use emacs, you will
need to install it first (from the Ubuntu Software Center).
● Start the terminal (Dashboard→ Terminal) and inside the terminal, navigate to the directory
when the asst01 file was placed. The ls (list files) and cd (change directory)
commands will be useful. Refer to the UNIX Terminal Command Line Summary Sheet (on the
class web page) for information on additional terminal commands.
● Assemble the program using the provided makefile. Use the following command:
make ast01
The make file will assemble and then link the program
● Execute the program in the debugger. Use the following debugger command
ddd ast01
You will probably want to display the line numbers (Source → Display Line Numbers)
● Start the DDD debugger
○ Execute the program in the debugger.
■ Set a break point at the end of the program.
■ Page down the line number of first instruction after the label last (~ line 188), right
click, and select set breakpoint option. You will see a “Stop” sign (on the right) when
the breakpoint is set. Alternately, you can type “break last” in the bottom window at the
(gdb) prompt.
○ Run the program.
■ Click on the Run option of the pop-up DDD menu. Alternately, you can type “run” in
the bottom window at the (gdb) prompt.
■ Note, you must set a breakpoint or the program will run and terminate (so you will not
be able to check the results).
○ Display the variables:
■ Become familiar with to to set breakpoints, the run and cont commands and the examine
memory command (x/ &varName).
■ Refer to the debugger information for additional explanation.
○ Create a Debugger output file
■ Download the assignment #1 debugger input file.
■ In the debugger, at the (gdb) prompt, read the commands (from the file) via:
source
■ Where is the name of the assignment #1 debugger input file previously
downloaded (a1in.txt by default). If the default file name is used, the command would
be:
source a1in.txt
■ Note, the debugger may prompt for Restart or Exit. If everything worked, you may
choose Exit to terminate the debugger session.
■ The a1in.txt debugger input file creates and output file named a1out.txt where
the results are placed.
○ Refer to the text, x86-64 Assembly Language Programming with Ubuntu, Chapter 6 for
detailed information and complete examples for using the DDD debugger.
Submission:
• All source files must assemble and execute on Ubuntu with yasm.
• Submit source file
◦ Submit a copy of the program source file via the on-line submission
• Once you submit, the system will score the project and provide feedback.
◦ If you do not get full score, you can (and should) correct and resubmit.
◦ You can re-submit an unlimited number of times before the due date/time.
• Late submissions will be accepted for a period of 24 hours after the due date/time for any given
assignment. Late submissions will be subject to a ~2% reduction in points per an hour late. If
you submit 1 minute – 1 hour late -2%, 1-2 hours late -4%, … , 23-24 hours late -50%. This
means after 24 hours late submissions will receive an automatic 0.
Program Header Block
All source files must include your name, section number, assignment, NSHE number, and program
description. The required format is as follows:
; Name:
; NSHE ID:
; Section:
; Description:
Failure to include your name in this format will result in a loss of up to 20%.
Scoring Rubric
Scoring will include functionality, code quality, and documentation. Below is a summary of the
scoring rubric for this assignment.
Criteria Weight Summary
Assemble – Failure to assemble will result in a score
of 0.
Program Header 30% Must include header block in the
required format (see above).
General Comments 30% Must include an appropriate level of
program documentation.
Program Functionality
(and on-time)
40% Program must meet the functional
requirements as outlined in the
assignment. Must be submitted on time
for full score.
