[maemo-developers] Java acceleration/Jazelle

[From: Simon Pickering]

Not such good news.

I have learned alot about extended inline asm though.

Anyway, my final code is here: 
http://people.bath.ac.uk/enpsgp/nokia770/jazelle/jazelle1.c

It's changed a fair bit from my first untested code and should now work 
as planned. Unfortunately what happens is a segfault. So this 
immediately rules out the premise that the code pointed to by R12 is 
jumped to (I called bxj with both r12 and r14 as its argument, same 
results both times). If the bxj Rn is removed then the segfault goes 
away, so this appears to be causing it.

I suppose the next step is to check and see which register is required 
to pass the Java bytecode address, and then try all other registers 
pointing to the bytecode 'handler' arm code to see if one doesn't 
produce a segfault. I'm assuming the segfault is caused because the 
process is trying to jump to an illegal address (because the relevant 
register is not set). Any other suggestions?

Thanks,


Simon