forums.ps2dev.org

sakya · Joined: 28 Apr 2006 Posts: 190

Hi! :)

First: this is not my code, I simply got the code from crazyc and SamuraiX and made it easy to use (at least for me). ;)
Original thread: http://forums.ps2dev.org/viewtopic.php?t=9564
Maybe it's usefull for someone else...

What is this?
This is a prx to handle exception on PSP, when an exception is raised some usefull information are shown on the display (and can be dumped to a text file).

How to compile it
Enter the prx directory and simply type

TyRaNiD · Joined: 18 Jan 2004 Posts: 918

Why do you use your own exception code (well actually just taken from other sources anyway) when you can just call pspDebugInstallErrorHandler from the sdk, geez some people :P

sakya · Joined: 28 Apr 2006 Posts: 190

Hi! :)

crazyc · Joined: 17 Jun 2005 Posts: 410

J.F. · Joined: 22 Feb 2004 Posts: 2906

SNES9xTYL has pspDebugInstallErrorHandler in its init code, but it had to be disabled with #ifdef to get the app to work in 3.xx. You cannot successfully call that function from a user mode prx in 3.xx - at least not from what I've seen. Having this as a prx with a simple init call to set it up is better for apps in any case. That allows the exception handling to be independent of the app, and simple to use in the app. If any more changes occur with the exception handling, it also means that it can be handled merely by changing the prx and not the entire app.

I plan to start using this in all my stuff. Many thanks to crazyc and sakya for this useful tool. :)

SamuraiX · Joined: 31 Jan 2006 Posts: 76 Location: USA

If I remember correctly it wasn't the fact you couldn't use pspDebugInstallErrorHandler(). It was the fact that you couldn't use pspDebugScreenPrintf() in a kernel mode prx for the dump. There would be linker errors for missing libraries for debug printing to screen.

crazyc · Joined: 17 Jun 2005 Posts: 410

Two things. In your init code, you have

SamuraiX · Joined: 31 Jan 2006 Posts: 76 Location: USA

hlide · Joined: 10 Sep 2006 Posts: 750

TyRaNiD · Joined: 18 Jan 2004 Posts: 918

Of course in prxtool you can pass the --reloc parameter and get it to the location it really is in memory ;)

M.Jackson · Joined: 10 Sep 2007 Posts: 85

This is probably an unrelated question. But is this installable exception handler a "true" exception handler for Allegrex (which suggests it can handle all exceptions/traps like clock interrupt or data/instruction bus error), or just one of the cascaded exception handlers managed by the firmware's exception/trap subsystem?

I am asking this because I saw there were code preserving the CPU status at the beginning of the handler, and if it was a cascaded handler it probably would not need to do so as the firmware's trap subsystem would have had the status preserved instead and passed it to our installed handlers, I guess.

TyRaNiD · Joined: 18 Jan 2004 Posts: 918

No you need to handle the register saving yourself the kernel doesn't do it for you even though this uses the default exception handler.

Basically other types of exception handle register saving in the different ways, for example a syscall doesn't really need to preserve anything bar enough to get it to return.

sakya · Joined: 28 Apr 2006 Posts: 190

Hi! :)

Can someone help me with this exception infos, please?

moonlight · Joined: 26 Oct 2005 Posts: 567

a breakpoint exception? That is usually done by an application on purpose, or
generated by the compiler when there is a division by zero.

That report isn't enough. Post some fragment of asm at least from text+0x8f50 to 0x8f80

sakya · Joined: 28 Apr 2006 Posts: 190

Hi! :)

coolkehon · Joined: 20 Oct 2008 Posts: 355

got that same error above with the relocation and i cant figure out how to fix any suggestion would be appreciated

J.F. · Joined: 22 Feb 2004 Posts: 2906

Those kinds of errors tend to be from the small data segment. If you see something like -G8 in your makefile, that's telling the compiler to try to put everything <= 8 bytes in size into the small data segment. This doesn't work very well on newer versions of gcc, so you see -G0 on many projects today.

coolkehon · Joined: 20 Oct 2008 Posts: 355

still cant find but here is the makefile

J.F. · Joined: 22 Feb 2004 Posts: 2906

That's a really non-standard PSP project makefile. :)

I noticed you have both -G4 and -G0 in the CFLAGS line. Remove the -G4 and see what happens - I don't know which would have priority, the -G4 or the -G0. Just use one.

coolkehon · Joined: 20 Oct 2008 Posts: 355

tried all of that to no aval it still doesnt work even removed both

coolkehon · Joined: 20 Oct 2008 Posts: 355

so is there no solution for this and if it helps i'm using cpp for the whole project but this file is .c i externed the initExceptionHandler() function so that it would be c

J.F. · Joined: 22 Feb 2004 Posts: 2906

Well, take a look at the DaedalusX64 makefile - DX64 uses the exception handler as well.

coolkehon · Joined: 20 Oct 2008 Posts: 355

started using psplink but now how do i i calc with the calc $epc-$mod because it says mod not found

willow :--) · Joined: 13 Jan 2007 Posts: 126

Sakya, would you recommend me to use your prx for my use case?

I have lots of stupid crashes in my application. It heavily relies on external content and I cannot control everything. I want my game to smoothly handle errors, and quit, rather than crash + having to reboot the PSP.

I use JGE, which already has exception handling code, but as it's been mentioned, this works only on 1.xx in kernel mode:
http://code.google.com/p/jge/source/browse/trunk/JGE/JGE/src/main.cpp#170

I like the idea of an external prx, and just want to make sure I'm using the best || most recent || most convenient solution out there

Edit: tried it, it does exactly what I want, thanks :)
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