RFR: 8198528: Move GenerationSpecs from GenCollectorPolicy to GenCollectedHeap

[Kim Barrett]

> On Feb 21, 2018, at 4:27 PM, Stefan Karlsson <stefan.karlsson at oracle.com> wrote:
> 
> Hi all,
> 
> Please review this patch to move _young_gen_spec and _old_gen_spec out from GenCollectorPolicy into GenCollectedHeap.
> 
>  http://cr.openjdk.java.net/~stefank/8198528/webrev.01/
>  https://bugs.openjdk.java.net/browse/JDK-8198528
> 
> This is a step towards the removal of CollectorPolicy:
> 
>  https://bugs.openjdk.java.net/browse/JDK-8198505
> 
> Thanks,
> StefanK

Generally looks good.  Just a few minor comments.

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src/hotspot/share/gc/cms/cmsHeap.cpp
  66 CMSHeap::CMSHeap(GenCollectorPolicy *policy) :

The new formatting of the initializer list is oddly indented.  I
suppose it's to make the initializer list visually distinct from the
body code.  I prefer accomplishing that by putting the open-brace of
the body on its own line between the initializer list and the body
code, rather than unusual indentation of the initializer list.

Similarly for the SerialHeap constructor.

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src/hotspot/share/gc/shared/genCollectedHeap.cpp
123 void GenCollectedHeap::initialize_generations(Generation::Name young,

Shouldn't this function just be removed now?

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src/hotspot/share/gc/shared/genCollectedHeap.cpp
 187 GenerationSpec* GenCollectedHeap::young_gen_spec() const {
 188   assert(_young_gen_spec != NULL, "_young_gen_spec should have been initialized");
 189   return _young_gen_spec;
 190 }
 191 
 192 GenerationSpec* GenCollectedHeap::old_gen_spec() const {
 193   assert(_old_gen_spec != NULL, "_old_gen_spec should have been initialized");
 194   return _old_gen_spec;
 195 }

The assertions are no longer useful, and indeed somewhat confusing,
since those members are now initialized in the constructor's
initializer list.

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