SpotLess debugger

@kas1e

Belated response after finding this. As a beta tester I have all sorts of OS4 volumes in various states on my system. Main, public, beta, stable, fresh in testing. So I can check software across various OS4 installs. Provided they can boot.

I'm not restricted by one old system. However, I have found the newer beta graphic modules build on the work of Update 2, and are even more buggy on my hardware. Once I was able to boot my beta volume by disabling compositing but now it acts faulty after running AmiUpdate. So nothing's changed and the old graphic bugs remain. Somehow AmuUpdate is good at reproducing graphic bugs. Be handy if AmiUpdate had a CLI mode. Be more handy if the bug was found that was introduced in Update 2 so I would have a stable system I can trust and not have a mix of testing volumes messing up the place.

is there such a thing as a fresh version of os4? seems pretty dead?

Maybe to the outside "community", although there is still plenty happening internally.

Simon

@Rigo

would there be a possibility to share some of *what* is happening "internally" exactly with mere end-users?

i mean, i don't need no nda stuff, but the "outside community" is what this is meant to be aimed for, isn't it?

being a non-betatester nowadays feels like being a windows or linux users...no news, no updates and, with every passing day, not really caring anymore either sadly...

actually, i'm reached the point of, whenever my hardware should die, I'd drop the amiga game completely...with the lack of PR and completely over the board secrecy going on regarding the os, I'd rather not spend any more hard earned money, time and nerves

thank you

As I start playing with A1222+ and SPE + AltiVec SIMD programming, I am looking for debugger. On os4coding.net I found Spotless and Debug101.
They look very nice, but worked only for small examples. My bigger project crashes.
I found in this topics, that problem is with many different os4 kernels and libraries.
So now I am using gdb... ( Big thanks @kas1e for gdb tutorial ! )

Please, are there some advice what kernel versions I should have to use Spotless? Or at least how can I use it without required libraries.

And second question: Which dissassemler do you use ( ideally I need some with AltiVec and SPE extensions)
Thaks for any advice..

@sailor

Thsnks for trying out Spotless. As you mention, it relies on modules, that might or might not get released at some point. Also, it has not been updated for a long while, and it lacks quite a lot of functionality, for instance debugging of libraries.

I think your best bet is to go with gdb atm. It is actively being worked on, and it has a more solid and all-encompasing foundation compared to Spotless. Spotless is more like a proof-of-concept, although it could potentially be worked on to create a fullblown debugger. Also it has some nice gui features like the MemorySurfer and split window mode.

@elfpipe
thank you for effort. Spotless in very nice piece of software an looks very easy to use.
I will make more Spotless testing, what works and what no so good.

In meantime i found, that most problems was with debugging my -O3 and vectorized code: for example, if I place breakpoint to some function, and in heavily optimized code exist symbol with function name, but function itself not exists, because it was unrolled directly to main() body.
So I will made more testing with -O0...

We have (me and elfpipe) added and fixed a lot of stuff in latest Spotless. It is open source so maybe if you find something to fix we can apply the patches

IMHO best debugging for "sunday sometimes" programmers is massive use of "printf" in #ifdef #endif blocks.
So you can have easily a debug or a release build modifing only a single parameter.

If you want look inside generated asm code with GCC you have to use "-S" and "-mregnames" mixed with others parameters too like "-O1" "-O2" "-O3" and others.
In this way you can appreciate also compiler's optimizing patterns and strategies, it works also for Altivec and SPE code.

Make a good debugger for AmigaOS is not trivial.

@flash
thanks, I forgot to regnames - good tip!
And printf+ifdef is really good tool - I was using it in the last millenium, and using it still

BTW, I found there is CodeWarrior Development Studio for Power
Architecture from NXP. Even is the version for QorIQ CPU (=P1022). Did somebody test it?
At least for disassembler.

Because I am not found yet SPE capable disassembler.VdaPPC has AltiVec support, but not SPE.
SPE and Altivec instruction opcodes partially overlapping, so with VdaPPC I can check if there is SPE-SIMD code, but not easilly read the code.

Now I am tried debuggging of stream SPE SIMD version.

Using of -O3 make debugging unstable.
Use of -O0 -mregnames works fine. So Spotless ( and db101 ) can be used even on A1222+, with some limitations - for example embedded GPR 64-bit extension not visible.

But it is fine, basic algorithms should be debugged with this nice easy-to-use tools ( many thanks to authors ), and final check should be done with gdb.

@sailor

I have not been too involved with the latest developments, so maybe I am not the right person to ask for those extensions to the codebase. I barely did any of the thinking with regards to those two debuggers myself, mostly just picked up on knowledge about the exec debugging interface, tutorials on creating simple debuggers etc. The issues you are seeing with optimized code is a good example of where my development skills hit the brick wall - I simply don't have a concept of how to improve on the basic algorithm.

Thanks for the test case, at least we know, that the tool is has some appeal for simple use cases.