Simulation halted by internal error when generating timing diagram

[krisjdev]

I'm trying to create a timing diagram of a CPU whilst its executing a program, however it fails with the following error:

java.lang.ArrayIndexOutOfBoundsException: Index 2 out of bounds for length 2
        at com.cburch.logisim.gui.log.Signal.extend(Signal.java:95)
        at com.cburch.logisim.gui.log.Model.extendWithNewValues(Model.java:570)
        at com.cburch.logisim.gui.log.Model.updateSignalsClockMode(Model.java:671)
        at com.cburch.logisim.gui.log.Model.propagationCompleted(Model.java:598)
        at com.cburch.logisim.gui.log.LogFrame$MyListener.propagationCompleted(LogFrame.java:86)
        at com.cburch.logisim.circuit.Simulator.firePropagationCompleted(Simulator.java:482)
        at com.cburch.logisim.circuit.Simulator$SimThread.loop(Simulator.java:373)
        at com.cburch.logisim.circuit.Simulator$SimThread.run(Simulator.java:383)

And it also produces a pop-up window that tells me to save my work and reload Logisim. I'm not able to restart the simulation using CTRL+E

I am using v3.8.0 installed using the .deb package.

To reproduce:

1. Download BABY.circ and TuringLongDivision.logisimRAMImage from https://gitlab.com/charles.fox/comparch/-/tree/main/chapter07
2. Open BABY.circ and load the TuringLongDivision.logisimRAMImage into the RAM block
3. Change the frequency: Simulate -> Auto-Tick Frequency -> 16.0 Hz
4. Open the timing diagram utility: Simulate -> Timing diagram
   1. Enable Store unlimited history
   2. Set timescale to 5.0us
   3. Do not add/remove any signals
5. Click into the Timing diagram tab in the utility
6. Start the simulation: Simulate -> Auto-Tick Enabled
7. Wait for it to crash, happens when the chronogram hits 2ms

I suspect that turning on Store unlimited history might be the cause of the issue, as the simulation runs as intended with it disabled, but I was hoping to export the waveforms generated during the entire duration of the program execution.

[maehne]

Thanks for the report! Could you please first test with the latest nightly build whether the issue persists? There have been quite some bug fixes since the last official release.

[krisjdev]

Hey, thanks for getting back to me. Just tried it with logisim-evolution_main_20240516_amd64.deb and ran into the same crash with the same error message:

java.lang.ArrayIndexOutOfBoundsException: Index 2 out of bounds for length 2
        at com.cburch.logisim.gui.log.Signal.extend(Signal.java:95)
        at com.cburch.logisim.gui.log.Model.extendWithNewValues(Model.java:569)
        at com.cburch.logisim.gui.log.Model.updateSignalsClockMode(Model.java:670)
        at com.cburch.logisim.gui.log.Model.propagationCompleted(Model.java:597)
        at com.cburch.logisim.gui.log.LogFrame$MyListener.propagationCompleted(LogFrame.java:86)
        at com.cburch.logisim.circuit.Simulator.firePropagationCompleted(Simulator.java:700)
        at com.cburch.logisim.circuit.Simulator$SimThread.loop(Simulator.java:526)
        at com.cburch.logisim.circuit.Simulator$SimThread.run(Simulator.java:538)

[maehne]

@arkis-s: Thanks for your testing with the latest nightly! I am not sure how fast we'll be able to fix the root cause, as the chronogram code was not developed by the current main developers. Maybe, @kevinawalsh already bumped on this bug in his Holy Cross fork of Logisim-evolution, as issue kevinawalsh#7 sounds similar.

[krisjdev]

Fair enough, thanks for letting me know :) In the meantime I'll just export the HDL and use it in some other simulator.