KUDOS: How do I halt the simulator?

[oleks]

I thought syscall was the way?

This seems to run forever: DIKU-EDU/kudos@cb64335

[JanmanX]

Right now, the simulator is hardcoded to exit on syscall, when $v0 = 10. The value in $v1 is returned as a result.

[oleks]

You mean like this? KUDOS still runs forever..

DIKU-EDU/kudos@8f8c781

[JanmanX]

The code at DIKU-EDU/kudos@8f8c781 should work (unless $v0 is not 10 after the ORI).

I've found some issues with address translation, getting the simulator stuck in certain conditions. I suspect the simulator does not even reach the exit code. I will investigate further.

[JanmanX]

Commit b05e449 seems to be able to successfully run the minimal version of KUDOS, with this code in kudos/init/mips32/_boot.S

  #  ori v0, 10                                                                 
  jal init                                                                      

  addi v0, $0, 10                                                                                                     
  syscall 

(I am not quite sure why $v0 is set prior jumping to init, nor why it is set using ORI?)

[oleks]

Right, I made a typeo!

[oleks]

A typeo wrt. to putting ori before jumping to init, and not giving it an two arguments. I don't understand why that even compiles.. I used ori out of habit as it can be used as you use addiu, but doesn't require the support of signed/unsigned operations in a simulator.

[JanmanX]

A shutdown device has been implemented in the simulator, but the "$v0 = 10, syscall" method will still remain in the simulator for now, as a fail-safe shutdown method.