Laboratory: Exploring Compilation

Due: 11 p.m., Wednesday, 7 September 2011

Summary: In this lab, you will explore various issues in compilation. While you have used a compiler before (or I hope you have), I expect you haven't thought much about various options and details.

Disclaimer: You come to this lab with widely varying backgrounds. Some of you have programmed in Java, some of you haven't; some of you have written (or read) some assembly language, some of you haven't; some of you are Unix experts, some of you aren't. Don't worry if you can finish it in five minutes. Don't worry if it takes awhile to get through the steps (but don't spend more than two hours).

Collaboration: Feel free to work on this lab in pairs or trios.

Turning It In: Save your answers in a plain text file and upload it to Pioneerweb.

Grading: I expect that you will gain more from doing this lab than from me grading this lab. I will simply scan through your answers to see if you had any particularly valuable insights. I will grade this lab on a plus/check/minus scale.

Preparation:

Create a directory for this lab.

Make a copy of the files for this lab.

Questions:

• 1. GCC's Stages
• 2. A Sample C Program
• 3. C vs. Pascal
• 4. GCC's Intermediate Representations, Revisited

1. GCC's Stages

Read information on the GNU Compiler Collection (gcc) and determine which of its intermediate program representations are available to you. You might use man or info to learn more about gcc.

Summarize the intermediate representations available to you.

2. A Sample C Program

Generate intermediate representations from twos.c and scan through those that you can read.

What, if anything, did you learn about the intermediate representations?

3. C vs. Pascal

The programs hellop.p and helloc.c print the phrase Hello World. Generate assembly for both programs.

How do the results differ? How are they similar?

4. GCC's Intermediate Representations, Revisited

Look on the Web for internal documentation on GCC. Explore which, if any, internal program representations are available to those building new GCC compilers.

Describe, in as much detail as you deem appropriate, the intermediate representations available and their purpose.