RFR: 8221260: Initialize more class members on construction, remove some unused ones

[Kim Barrett]

> On Mar 21, 2019, at 3:33 PM, Leo Korinth <leo.korinth at oracle.com> wrote:
> 
> Hi,
> 
> This is a code cleanup. This change removes some warnings when opening the files from within Eclipse.
> 
> I try to:
> - Initialize more class members as soon as possible
> - Remove some (5) unused members, and one unused faulty constructor
> - Prefer to use initializer list instead of constructor body
> 
> Enhancement:
> https://bugs.openjdk.java.net/browse/JDK-8221260
> 
> Webrev:
> http://cr.openjdk.java.net/~lkorinth/8221260/00
> 
> Testing:
> Mach5 tier1-3
> 
> Thanks,
> Leo

Having wasted way too many hours debugging unitialized data members,
I'm in favor of this sort of thing.  Looks good, other than a couple
minor things below for which I don't need a new webrev.

Nice find: PSFileBackedVirtualSpace constructor.  I was trying to
figure out how this even compiled pre-C++11 delegating constructors,
and then realized that was a curly-brace and not a colon.

------------------------------------------------------------------------------ 
src/hotspot/share/gc/parallel/psMarkSweepDecorator.hpp
59     _allowed_dead_ratio(allowed_dead_ratio){ }

Add a space before the curly-brace.

------------------------------------------------------------------------------ 
src/hotspot/share/gc/parallel/psParallelCompact.cpp
410 #ifdef  ASSERT
411   _region_end(NULL),
412 #endif  // #ifdef ASSERT

This can be done more compactly as

  DEBUG_ONLY(_region_end(NULL) COMMA)

Your choice...

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