Syllabus🔗

Introduction to Compilers, CMSC 430

Term: Fall, 2024

Professor: David Van Horn (he/him)

Email: dvanhorn@cs.umd.edu

Office Hours: By appointment. Send email or ELMS message to set up.

Prerequisite: a grade of C or better in CMSC330; and permission of department; or CMSC graduate student.

Credits: 3.

Lectures: TTh, 2:00-3:15pm, LEF 2205 (DVH)

Course Description: CMSC 430 is an introduction to compilers. Its major goal is to arm students with the ability to design, implement, and extend a programming language. Throughout the course, students will design and implement several related high-level programming languages, building compilers that target the x86 CPU architecture.

The course assumes familiarity with a functional programming such as OCaml from CMSC 330, and, to a lesser extent, imperative programming in C and Assembly as covered in CMSC 216.

Course Structure: The course will consist of in-person lectures, which will be recorded and available on ELMS immediately after each lecture. There are two midterms, a final project, which counts as the final assessment for the class, several assignments, and several quizes and surveys. Midterms are take-home exams and completed online over a 24 period.

Contents:

1 Policies and Resources for Undergraduate Courses🔗

It is our shared responsibility to know and abide by the University of Maryland’s policies that relate to all courses, which include topics like:

• Academic integrity

• Student and instructor conduct

• Accessibility and accommodations

• Attendance and excused absences

• Grades and appeals

• Copyright and intellectual property

Please visit https://www.ugst.umd.edu/courserelatedpolicies.html for the Office of Undergraduate Studies’ full list of campus-wide policies and follow up with the instructor if you have questions.

2 Course Guidelines🔗

Names/Pronouns and Self-Identifications: The University of Maryland recognizes the importance of a diverse student body, and we are committed to fostering inclusive and equitable classroom environments. We invite you, if you wish, to tell us how you want to be referred to in this class, both in terms of your name and your pronouns (he/him, she/her, they/them, etc.). Keep in mind that the pronouns someone uses are not necessarily indicative of their gender identity. Visit https://trans.umd.edu to learn more.

Additionally, it is your choice whether to disclose how you identify in terms of your gender, race, class, sexuality, religion, and dis/ability, among all aspects of your identity (e.g., should it come up in classroom conversation about our experiences and perspectives) and should be self-identified, not presumed or imposed. Course staff will do their best to address and refer to all students accordingly, and we ask you to do the same for all of your fellow Terps.

Communication with Instructor:

Email: If you need to reach out and communicate with David Van Horn, please email at dvanhorn@cs.umd.edu. Please DO NOT email questions that are easily found in the syllabus or on ELMS (i.e. When is this assignment due? How much is it worth? etc.) but please DO reach out about personal, academic, and intellectual concerns/questions.

ELMS: IMPORTANT announcements will be sent via ELMS messaging. You must make sure that your email & announcement notifications (including changes in assignments and/or due dates) are enabled in ELMS so you do not miss any messages. You are responsible for checking your email and Canvas/ELMS inbox with regular frequency.

Communication with Peers:

With a diversity of perspectives and experience, we may find ourselves in disagreement and/or debate with one another. As such, it is important that we agree to conduct ourselves in a professional manner and that we work together to foster and preserve a virtual classroom environment in which we can respectfully discuss and deliberate controversial questions. We encourage you to confidently exercise your right to free speech—bearing in mind, of course, that you will be expected to craft and defend arguments that support your position. Keep in mind, that free speech has its limit and this course is NOT the space for hate speech, harassment, and derogatory language. We will make every reasonable attempt to create an atmosphere in which each student feels comfortable voicing their argument without fear of being personally attacked, mocked, demeaned, or devalued.

Any behavior (including harassment, sexual harassment, and racially and/or culturally derogatory language) that threatens this atmosphere will not be tolerated. Please alert the instructor immediately if you feel threatened, dismissed, or silenced at any point during the semester and/or if your engagement in discussion has been in some way hindered by the learning environment.

3 Office Hours🔗

Office hours will be held online and in-person. Details TBD.

4 Topics🔗

The following list of lecture topics will vary according to the pace of the course:

• Overview of compilation

• Operational semantics

• Interpreters

• Intermediate representations and bytecode

• Code generation

• Run-time systems

• Garbage collection

• Type systems, type soundness, type inference

• Register allocation and optimization

• Language design

• Advanced topics in compilation

5 Grades🔗

All assessment scores will be posted on the course ELMS page.

Late work will not be accepted for course credit so please plan to have it submitted well before the scheduled deadline.

Any formal grade disputes must be submitted in writing and within one week of receiving the grade. Final letter grades are assigned based on the percentage of total assessment points earned. To be fair to everyone I have to establish clear standards and apply them consistently, so please understand that being close to a cutoff is not the same as making the cut (89.99 ≠ 90.00). It would be unethical to make exceptions for some and not others.

Your final course grade will be determined according to the following percentages:

Final letter grades will be assigned based on the following cutoff table:

6 Videos🔗

Lectures will be recorded and posted to ELMS shortly after every class. There are also prepared videos available covering the material.

These videos will be made available as the course progresses. If there is ever any issue with accessing these videos, let the instructor know as soon as possible.

7 Assignments🔗

There will be several programming Assignments, often with a full week given for completion and submission (e.g. if it assigned on a Tuesday it will be due the following Tuesday at 11:59pm EST unless otherwise noted).

Assignments will be submitted through Gradescope.

On the weeks were there are no programming assignments, there will be assigned reading.

8 Quizzes & surveys🔗

There will be many quizzes and surveys. These will be administered through ELMS. Completed surveys receive full credit. Instructors reserve the right to reject survey responses that are not considered thoughtful.

9 Midterms🔗

There will be two Midterms, which will be take-home exams. Exams will be distributed at least 48 hours before the due date of the midterm.

• Midterm 1: October 10

• Midterm 2: November 7

10 Project🔗

There will be a course Project that will be assessed during the final exam period for the course:

• Final Project Assessment: TBD

The project description will be distributed approximately 3 weeks before the due date.

11 Computing Resources🔗

Programming projects can be developed on your own system and subitted via Gradescope, which will provide virtual machines suitably configured for running your code. All project submissions must work correctly on the Gradescope VMs, and your projects will be graded solely based on their results on those machines. Because language and library versions may vary with the installation, in unfortunate circumstances a program might work perfectly on your system but not work at all on the VMs. Thus we strongly recommend that as you develop any project, you should run it several days early on Gradescope to have time to address any compatibility problems.

12 Outside-of-class communication with course staff🔗

Course staff will interact with students outside of class in primarily two ways: office hours, and electronically via e-mail. The use of Piazza and/or other classroom forums is allowed, and discussion amongst the students is encouraged, as long as the discuss is about the concepts and not the solutions. The majority of communication should be via office hours.

Personalized assistance, e.g., with assignments or exam preparation, will be provided during office hours. Office hours for the instructional staff will be posted on the course web page.

Additional assistance will provided via discussion on Piazza. You may use this forum to ask general questions of interest to the class as a whole, e.g., administrative issues or problem set clarification questions. The course staff will monitor it on a daily basis, but do not expect immediate answers to questions. Please do not post publicly any information that would violate the university academic integrity policy (e.g., problem set code).

Personal e-mail to TAs should be reserved for issues that cannot be handled by the above methods.

Important announcements will be made in class or on the class web page, and via Piazza.

13 Excused Absences🔗

Any student who needs to be excused for an absence from a single lecture or lab due to illness shall:

• Make a reasonable attempt to inform the instructor of his/her illness prior to the class.

• Upon returning to the class, present their instructor with a self-signed note attesting to the date of their illness. Each note must contain an acknowledgment by the student that the information provided is true and correct. Providing false information to University officials is prohibited under Part 9(h) of the Code of Student Conduct (V-1.00(B) University of Maryland Code of Student Conduct) and may result in disciplinary action.

Missing an exam for reasons such as illness, religious observance, participation in required university activities, or family or personal emergency (such as a serious automobile accident or close relative’s funeral) will be excused so long as the absence is requested in writing at least 2 days in advance and the student includes documentation that shows the absence qualifies as excused; a self-signed note is not sufficient as exams are Major Scheduled Grading Events. For this class, such events are the final project assessment and midterms, which will be due on the following dates:

• Midterm 1: October 10

• Midterm 2: November 7

• Final Project Assessment: TBD

The final exam is scheduled according to the University Registrar.

For medical absences, you must furnish documentation from the health care professional who treated you. This documentation must verify dates of treatment and indicate the timeframe that the student was unable to meet academic responsibilities. In addition, it must contain the name and phone number of the medical service provider to be used if verification is needed. No diagnostic information will ever be requested. Note that simply being seen by a health care professional does not constitute an excused absence; it must be clear that you were unable to perform your academic duties.

It is the University’s policy to provide accommodations for students with religious observances conflicting with exams, but it is the your responsibility to inform the instructor in advance of intended religious observances. If you have a conflict with one of the planned exams, you must inform the instructor prior to the end of the first two weeks of the class.

For missed exams due to excused absences, the instructor will arrange a makeup exam. If you might miss an exam for any other reason other than those above, you must contact the instructor in advance to discuss the circumstances. We are not obligated to offer a substitute assignment or to provide a makeup exam unless the failure to perform was due to an excused absence.

The policies for excused absences do not apply to project assignments. Projects will be assigned with sufficient time to be completed by students who have a reasonable understanding of the necessary material and begin promptly. In cases of extremely serious documented illness of lengthy duration or other protracted, severe emergency situations, the instructor may consider extensions on project assignments, depending upon the specific circumstances.

Besides the policies in this syllabus, the University’s policies apply during the semester. Various policies that may be relevant appear in the Undergraduate Catalog.

If you experience difficulty during the semester keeping up with the academic demands of your courses, you may consider contacting the Learning Assistance Service in 2201 Shoemaker Building at (301) 314-7693. Their educational counselors can help with time management issues, reading, note-taking, and exam preparation skills.

14 Students with Disabilities🔗

Students with disabilities who have been certified by Disability Support Services as needing any type of special accommodations should see the instructor as soon as possible during the schedule adjustment period (the first two weeks of class). Please provide DSS’s letter of accommodation to the instructor at that time.

All arrangements for exam accommodations as a result of disability must be made and arranged with the instructor at least three business days prior to the exam date; later requests (including retroactive ones) will be refused.

15 Academic Integrity🔗

The Campus Senate has adopted a policy asking students to include the following statement on each examination or assignment in every course: "I pledge on my honor that I have not given or received any unauthorized assistance on this examination (or assignment)." Consequently, you will be requested to include this pledge on each exam and assignment. Please also carefully read the Office of Information Technology’s policy regarding acceptable use of computer accounts.

Assignments and projects are to be completed individually, therefore cooperation with others or use of unauthorized materials on assignment or projects is a violation of the University’s Code of Academic Integrity. Both the person receiving assistance and the person providing assistance are in violation of the honor code. Any evidence of this, or of unacceptable use of computer accounts, use of unauthorized materials or cooperation on exams or quizzes, or other possible violations of the Honor Code, will be submitted to the Student Honor Council, which could result in an XF for the course, suspension, or expulsion.

• For learning the course concepts, students are welcome to study together or to receive help from anyone else. You may discuss with others the assignment or project requirements, the features of the programming languages used, what was discussed in class and in the class web forum, and general syntax errors. Examples of questions that would be allowed are "Does a cond expression always end with an else-clause?" or "What does a ’mismatched parenthesis’ error indicate?", because they convey no information about the contents of an assignment.

• When it comes to actually writing an assignment, other than help from the instructional staff, assignments must solely and entirely be your own work. Working with another student or individual, or using anyone else’s work in any way except as noted in this paragraph, is a violation of the code of academic integrity and will be reported to the Honor Council. You may not discuss design of any part of an assignment with anyone except the instructor and teaching assistants. Examples of questions you may not ask others might be "How did you implement this part of the assignment?" or "Please look at my code and help me find my stupid syntax error!". You may not use any disallowed source of information in creating either the design or code. When writing assignment you are free to use ideas or short fragments of code from published textbooks or publicly available information, but the specific source must be cited in a comment in the relevant section of the program.

Violations of the Code of Academic Integrity may include, but are not limited to:

• Failing to do all or any of the work on a project by yourself, other than assistance from the instructional staff.

• Using any ideas or any part of another person’s project, or copying any other individual’s work in any way.

• Giving any parts or ideas from your project, including test data, to another student.

• Allowing any other students access to your program on any computer system.

• Posting solutions to your projects to publicly-accessible sites, e.g., on github.

• Transferring any part of an assignment or project to or from another student or individual by any means, electronic or otherwise.

If you have any question about a particular situation or source then consult with the instructors in advance. Should you have difficulty with a programming assignment you should see the instructional staff in office hours, and not solicit help from anyone else in violation of these rules.

It is the responsibility, under the honor policy, of anyone who suspects an incident of academic dishonesty has occurred to report it to their instructor, or directly to the Honor Council.

Every semester the department has discovered a number of students attempting to cheat on assignments, in violation of academic integrity requirements. Students’ academic careers have been significantly affected by a decision to cheat. Think about whether you want to join them before contemplating cheating, or before helping a friend to cheat.

You may not share, discuss, or compare assignment solutions even after they have been graded since later assignments may build upon earlier solutions.

16 Course Evaluations🔗

If you have a suggestion for improving this class, don’t hesitate to tell the instructor or TAs during the semester. At the end of the semester, please don’t forget to provide your feedback using the campus-wide CourseEvalUM system. Your comments will help make this class better.

17 Right to Change Information🔗

Although every effort has been made to be complete and accurate, unforeseen circumstances arising during the semester could require the adjustment of any material given here. Consequently, given due notice to students, the instructors reserve the right to change any information on this syllabus or in other course materials. Such changes will be announced and prominently displayed at the top of the syllabus.

18 Course Materials🔗

Portions of the course materials are based on material developed by Ranjit Jhala and Joe Gibbs Politz.

We gratefully acknowledge the work of past CMSC 430 TAs William Chung, Pierce Darragh, Justin Frank, Vyas Gupta, Sankha Narayan Guria, Tasnim Kabir, John Kastner, Yiyun Liu, Dhruv Maniktala, Christopher Maxey, Deena Postol, Ivan Quiles-Rodriguez, Benjamin Quiring, Temur Saidkhodjaev, Matvey Stepanov, Alex Taber.