RFR: 8199946: Move load/store and encode/decode out of oopDesc

[Stefan Karlsson]

Hi,

This patch needs Erik's change to the LoadProxies:
http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2018-March/021504.html

to build on fastdebug.

Here's a rebased patch:
http://cr.openjdk.java.net/~stefank/8199946/webrev.02/

Thanks,
StefanK

On 2018-03-21 18:27, Stefan Karlsson wrote:
> Hi all,
> 
> Please review this patch to get rid of the oopDesc::load/store functions 
> and to move the oopDesc::encode/decode functions to a new CompressedOops 
> subsystem.
> 
> http://cr.openjdk.java.net/~stefank/8199946/webrev.01
> https://bugs.openjdk.java.net/browse/JDK-8199946
> 
> When the Access API was introduced many of the usages of 
> oopDesc::load_decode_heap_oop, and friends, were replaced by calls to 
> the Access API. However, there are still some usages of these functions, 
> most notably in the GC code.
> 
> This patch is two-fold:
> 
> 1) It replaces the oopDesc load and store calls with RawAccess equivalents.
> 
> 2) It moves the oopDesc encode and decode functions to a new, separate, 
> subsystem called CompressedOops. A future patch could even move all the 
> Universe::_narrow_oop variables over to CompressedOops.
> 
> The second part has the nice property that it breaks up a circular 
> dependency between oop.inline.hpp and access.inline.hpp. After the 
> change we have:
> 
> oop.inline.hpp includes:
>    access.inline.hpp
>    compressedOops.inline.hpp
> 
> access.inline.hpp includes:
>    compressedOops.inline.hpp
> 
> Thanks,
> StefanK