In my experience, some signals disappear from SignalTap possible nodes because of optimization.
I wanted to make aliases to several signals and tried using noprune so they will be available at SignalTap, but I didn't see them in any category (not in the Design List category nor in the pre-synthesis category). I am using Quartus 15.1
Is there any way to make alias for signal names so they will appear for sure in the Nodes list of SignalTap?
Best Answer
I post this self-answer here since it may help others.
My brute force method was to simply SAMPLE on a clocked process ALL the signals I wanted for SignalTap (since I sample them all, they will appear with one clock delay, but all of them with the same delay).
Then I applied to all of them the noprune attribute. It is rather cumbersome and ugly, but it worked.