RFR(S): 8247516: DSO.closestSymbolToPC() should use dbg.lookup() rather than rely on java ELF file support

[Chris Plummer]

I should have mentioned that currently there is no testing of this code. 
There will with the changes for [1] JDK-8247514, which will add the lost 
clhsdb "whatis" functionality, which was lost when JavaScript support 
went away. "whatis" used DSO.closestSymbolToPC(), so as part of 
JDK-8247514 I'm adding this support to the PointerFinder class so the 
"findpc" will also be able to do address to native symbol lookups, and 
the ClhsdbFindPC will check that it is working.

[1] https://bugs.openjdk.java.net/browse/JDK-8247514

thanks,

Chris

On 7/27/20 9:32 PM, Chris Plummer wrote:
> Hello,
>
> Please review the following:
>
> https://bugs.openjdk.java.net/browse/JDK-8247516
> http://cr.openjdk.java.net/~cjplummer/8247516/webrev.00/index.html
>
> I put all the details in the description of the CR, including some 
> background on how symbol lookups are done, including what LoadObjects 
> are and their class hierarchy, and also info on JVMDebugger subclasses.
>
> One thing not covered in the bug description is the additional gutting 
> of DSO.java that comes with these changes. Many APIs were not used so 
> I removed them, such as setBase(), lookupSymbol(), and isDSO(). Doing 
> so allowed completely severing any need for java ELF file support. 
> Note I plan on removing the java ELF file support itself with another 
> CR after pushing these changes.
>
> thanks,
>
> Chris