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Lab02 - Introduction to RISC-V Assembly Programming

Code due Wed Sep 3rd by 11:59pm in your Lab02 GitHub repo

Tests: https://github.com/USF-CS315-F25/tests

Autograder: https://github.com/phpeterson-usf/autograder

GDB Setup for Assembly Debugging

On the BeagleV machines, you can a gdbinit file to get a nice UI for assembly language debugging. The file should be in ~/.config/gdb/gdbinit. If you don't have a ~/.config you will have to create it. If you don't have ~/.config/gdb you will have to create it. You can use mkdir -p to create everything at once:

$ cd
$ mkdir -p ~/.config/gdb
$ cd .config/gdb
$ cat > gdbinit
set auto-load safe-path /
set debuginfod enabled off
tui new-layout asm {-horizontal src 1 regs 1} 2 status 0 cmd 1
tui enable
layout asm
^d
Note ^d means type CTRL-d to close the file.

See GDB Usage for links to GDB tutorials.

Given

You will be given a Makefile, C files, and Assembly files (.s). We will use this given structure for most of our Assembly Language programming. For example, you are given:

add2.c  add2_c.c  add2_s.s

The add2.c file is the main program for the add2 functions. The add2_c.c file is the C implementation and the add2_s.s is the Assembly implementation. These are all linked together with the Makefile. And when we run it, we get:

benson@beagle4:lab02-starter$ ./add2 3 4
C: 7
Asm: 7

That is the add2 program calls the C version and the Assembly version with the same arguments and the goal is to get the same results.

You are also given a full implementation of mul2.

Requirements

  1. You will develop RISC-V assembly language implementations of the following arithmetic problems. You will be given the C implementations, you need to write the RISC-V implementations.
  2. Your executable must be compiled with a Makefile
  3. Before you add files to your repo, do a $ make clean so you don't add/commit build products like executables or .o files
  4. We will test the labs using autograder

add4: Adds four 32-bit integers together and returns the result. Example:

$ ./add4 1 2 3 4
C: 10
Asm: 10

mul4: Multiplies four 32-bit integers together and returns the result. Example:

$ ./mul 1 2 3 4
C: 24
Asm: 24

Rubric

  1. Your lab will receive the score indicated by the autograder
  2. To get the test cases, git pull in the tests repo