Peer-review -- Sami Vuorijärvi

Lab 1a review

Your implementation of lab1a looks good overall, good work! But, there’s a couple of things to address.

General

✅ Repo structure follows the original.

✅ All required files are present.

The code

✅ Code builds without errors.

✅ Code follows lab instructions regarding fp, sp and ra.

✅ Illustration of the stack frame looks correct.

The compiled program

❌ The program produces the correct result.

❌ The resulting reversed string is placed correctly.

✅ The resulting string is zero terminated.

✅ The program reaches infinite loop when finished.

✅ The code has passed CI.

Comments:

When I compile your program and run it in SyncRim, the program doesn’t produce any output at all in outtext, except the terminating zero.

I’m not quite sure why that is since the code has passed CI. But looking at your code I believe the issue might be that you have allocated space on the stack for the local variables n, dst and src but I can’t see that you actually write anything to these.

For example:
53    lw    $t0, 4($fp)
54    beq   $t0, $zero, rev_ret
On row 53 you load the word from 4($fp) to $t0, and since you haven't written anything to 4($fp) before, $t0 is going to equal zero and on row 54 the program is going to branch to rev_ret causing the recursion to stop prematurely.

Take a look at this and leave a comment below to let me know when it’s fixed and I'll close the issue.