Okay, so let's re-ask google about that __ashrsi3 routine ... and a different implementation arrives in search results. Let's try it

__ashrsi3
And the execution result :
Execution result with second version of __ashrsi3 function 
Yeah, it works this time !!! And don't ask me why, because I didn't took time in understanding what's different in that second version of
__ashrsi3 function

And, rather than understanding why it works ... let's close that assembly pandora box before some other mystic bugs pop from it

I will probably see about this in the future, but that was absolutely out of the scope of today's programming, and in software world, too much digression leads to freeze of projects, which I would like to avoid in order to go forward to next pending project

As a example, I started to adapt yeti3d engine to Saturn in 2010 (7 years ago !), and this ended in ... developing a SD card based memory cartridge for Saturn !

The point above is is not a joke : menus used in my yeti3d adaptation are the origin of menus used in Pseudo Saturn Kai, which shows the continuity (co-consanguinity ?

) in my projects. And after getting yeti3d working a bit, I really would like to load levels from something else than CD-ROM, which was from PC (via adequate link cable) on a first time, and which will (should ?) then evolve to SD card.
That would be cool to make a Saturn game not requiring to burn CD-ROM somedays, but before that I need to finish neighboring side quests

Evolution of my Saturn projects 
To conclude this article, let's say it was terribly fun to see some bits of the internals behind C language

By the past, I remember I did something similar with my yeti3d adaptation, but remained at "C language level" : optimization done at that time was (IIRC, ) to avoid 4 bits shifts, because theses are not available in a single SH-2 CPU instruction. Avoiding 4 bits shifts was simply done by merging two fixed point operation in a single one (or something like that : I did this 7 years ago !), and this actually gave some improvements in 3D scene rendering

Theses were the good times ... I sometimes think "
I'm Getting Too Old For This Shit", but that's only to motivate to finish my old projects

But before that, Pseudo Saturn Kai, and then Kicad and Quartus are waiting for me

BTW, in the case you wondered about what was today's programming session, you probably guessed it was about exception handler addition to Pseudo Saturn Kai. This not a new feature, since it was available in Pseudo Saturn 0.83x ... in fact, I grabbed some sources from Pseudo Saturn 0.83x in order to implement this exception handler (thank you CyberWarriorX !)

This exception handler will be available as a small add-don to cheat codes feature in Pseudo Saturn Kai next major release.