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CS 315-01 Lecture/Lab — Fall 2025

Meeting Summary

  • Date: Sep 02, 2025
  • Time: 08:10 AM Pacific (US and Canada)
  • Meeting ID: 886 4953 2573

Quick Recap

The session reviewed Project 1 requirements and implementation details: Makefiles, separate compilation, and C programming concepts (structs, printf). Greg emphasized code quality, formatting, documentation, and adherence to team standards. The meeting concluded with an introduction to assembly programming, including RISC‑V (“RISC 5”) instructions, and announcements about upcoming lab activities and grading.

Next Steps

  • Complete Project 1 by tonight’s deadline.
  • Implement the num_info and num_conversion executables in the Project 1 repository.
  • Write custom conversion functions; do not use printf("%d"), printf("%x"), scanf, or atoi for required conversions. Use printf("%s") to print converted string values.
  • Always output results in fixed order from low base to high base, regardless of command-line option order.
  • Use separate compilation:
  • Factor shared helpers into num_helpers.c with a matching num_helpers.h.
  • Avoid putting logic in main; break code into smaller functions.
  • Create and update a Makefile:
  • Produce binaries for num_info and num_conversion.
  • Add targets for new object files and header dependencies.
  • Use a tab character for each rule’s action line.
  • Follow code quality standards:
  • Consistent formatting, spacing, and commenting.
  • Use spaces (not tabs) for indentation in source code.
  • Prefer snake_case over camelCase to match C library conventions.

Summary

Project 1: Compilation Guidelines

Greg outlined expectations for Project 1: - Use Makefiles and separate compilation; build num_info and num_conversion. - printf("%s") is allowed for outputting converted strings; avoid standard library conversion helpers for the assignment’s required conversions. - Output order is fixed (low base to high base), regardless of CLI option order. - Hexadecimal digits may be uppercase or lowercase. - Helper functions used in num_info may be reused in num_conversion.

C Code Refactoring and Compilation

  • Refactor common code into separate .c files with corresponding .h headers.
  • Place function prototypes in headers to provide type signatures.
  • Compile and link multiple C files with GCC; structure the Makefile to track object files and header dependencies so changes trigger correct recompilation.

Code Quality and Consistency Standards

  • Maintain consistent formatting and syntax for readability and maintainability.
  • Adhere to team standards used in open-source and professional codebases.
  • Prefer spaces for indentation to avoid tab/space alignment issues across editors and platforms.

C Code Quality and Structs

  • Prefer snake_case to align with C libraries and large codebases (e.g., the Linux kernel).
  • Break complex logic into smaller functions; keep main minimal.
  • Use structs to pass related data between functions; use pointers to structs and -> to access fields where appropriate.

C Programming Best Practices

  • It is acceptable to exit from within helper functions on fatal validation errors rather than unwinding back to main.
  • Maintain strong documentation and repository organization.
  • Follow the provided echo/config structure.
  • Office hours are available for assistance.

Git Practices and C Structs

  • Keep repositories clean: do not commit .o files or executables; use git rm to remove tracked binaries and artifacts.
  • For struct definitions:
  • Prefer explicit struct usage for clarity.
  • Use typedef judiciously (appropriate for complex types) but be aware it can obscure pointer semantics.

Project 1 Grading and Lab Updates

  • Combine C files as needed; prefer stack allocation over malloc. Dynamic allocation is discouraged to avoid memory issues in this course.
  • Grading for Project 1 will be offline (not interactive); feedback will be provided separately.
  • Tomorrow’s lab will be interactive with tasks focused on assembly; students must bring laptops and submit work by the end of the lab period.

Assembly Language Programming Basics

  • Demonstrated a simple C program alongside its assembly equivalent.
  • Covered labels, instructions, registers, and directives.
  • Showed how to compile and run assembly with GCC and explained the relationship among assembly, machine code, and the processor.
  • Introduced return values in assembly and how they differ from C.

RISC‑V Assembly Language Overview

  • Reviewed RISC‑V (“RISC 5”) instruction structure and strict formatting.
  • Explained register usage, including the zero register, and the difference between ADDI and ADD.
  • Discussed register naming conventions and 32-bit vs. 64-bit operation:
  • The machine uses 64-bit registers, but 32-bit values can be manipulated within them.
  • Students should review the RISC guide before the next lab, where they will begin writing assembly code.