Summary: Replace G1CodeRootSet with a Hashtable based implementation, merge Code Root Migration phase into Code Root Scanning
Reviewed-by: jmasa, brutisso, tschatzl

Reviewed-by: brutisso, tschatzl

Summary: Splitting out a g1 allocator class to simply specialized allocators which can associate each allocation with a given context.
Reviewed-by: mgerdin, brutisso

Summary: Allow G1 to decommit memory of arbitrary regions within the heap and their associated auxiliary data structures card table, BOT, hot card cache, and mark bitmaps.
Reviewed-by: mgerdin, brutisso, jwilhelm

Summary: Let HeapRegionSeq manage the heap region and auxiliary data to decrease the amount of responsibilities of G1CollectedHeap, and encapsulate this work from other code.
Reviewed-by: jwilhelm, jmasa, mgerdin, brutisso

Reviewed-by: tschatzl, jmasa

Reviewed-by: jwilhelm, jmasa

Reviewed-by: pliden, jmasa

Summary: Extend the WhiteBox API to provide information about the size and age of objects. Further add a mechanism to trigger a young GC.
Reviewed-by: tschatzl, sjohanss
Contributed-by: NLeonid Mesnik <leonid.mesnik@oracle.com>

Summary: Remove dead code.
Reviewed-by: stefank, brutisso

Summary: Remove dead code.
Reviewed-by: stefank, brutisso

Summary: Eager reclaim also needs to clear marks of eagerly reclaimed regions if they have already been marked during concurrent mark.
Reviewed-by: jmasa

Summary: Eager reclaim also needs to clear marks of eagerly reclaimed regions if they have already been marked during concurrent mark.
Reviewed-by: jmasa

Summary: Try to reclaim humongous objects at every young collection after doing a conservative estimate of its liveness.
Reviewed-by: brutisso, mgerdin

Summary: Try to reclaim humongous objects at every young collection after doing a conservative estimate of its liveness.
Reviewed-by: brutisso, mgerdin

Summary: Refactor preparation for compaction during Full GC so that it lazily initializes the first compaction point. This also avoids problems later when the first region may not be committed. Also reviewed by K. Barrett.
Reviewed-by: brutisso

Summary: Refactor preparation for compaction during Full GC so that it lazily initializes the first compaction point. This also avoids problems later when the first region may not be committed. Also reviewed by K. Barrett.
Reviewed-by: brutisso

Reviewed-by: brutisso, sjohanss

Summary: Removed all write barriers during reference processing and added explicit write barriers when iterating through the discovered list.
Reviewed-by: pliden, jmasa, tschatzl

Summary: Added -XX:+/-ClassUnloadingWithConcurrentMark
Reviewed-by: jmasa, brutisso, mgerdin

Reviewed-by: stefank, brutisso

Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov
Contributed-by: stefan.karlsson@oracle.com, mikael.gerdin@oracle.com

Summary: Rename save_marks to record_top_and_timestamp and remove som unused but related methods
Reviewed-by: stefank, ehelin

Reviewed-by: mgerdin, tschatzl

8043029: Change 8037816 breaks HS build with older GCC versions which don't support diagnostic pragmas
8043164: Format warning in traceStream.hpp
Summary: Backport of main fix + two corrections, enables clang compilation, turns on format attributes, corrects/mutes warnings
Reviewed-by: kvn, coleenp, iveresov, twisti

Summary: Only prune metaspace virtual spaces at safepoint so walking them is safe outside a safepoint.
Reviewed-by: mgerdin, mgronlun, hseigel, stefank

Reviewed-by: jmasa, tschatzl, ehelin
Contributed-by: tony.printezis@oracle.com, bengt.rutisson@oracle.com

Summary: temporarily disable the shutdown of the concurrent GC threads introduced in JDK-8037112
Reviewed-by: brutisso, tschatzl, jmasa

Reviewed-by: brutisso, mgerdin

Reviewed-by: sjohanss, jmasa

Summary: Fill the last card that has been allocated into with a dummy object
Reviewed-by: tschatzl, mgerdin

Reviewed-by: tschatzl, pliden

Reviewed-by: mikael, jmasa

Reviewed-by: tschatzl, jwilhelm

Reviewed-by: tschatzl, mgerdin, jmasa

Reviewed-by: jmasa, coleenp

Summary: Move G1ParCopyClosure::copy_to_survivor_space to decrease code size.
Reviewed-by: stefank, jmasa

Summary: Remove the assumption that G1CollectedHeap::in_cset_fast_test needs to check for NULL references. Most of the time this is not required, making the code doing this check multiple times.
Reviewed-by: stefank, mgerdin, jmasa

Summary: Move methods that are not dependent on any of G1ParCopyClosure's template parameters into G1ParCopyHelper. Further remove unused methods and members of the class hierarchy.
Reviewed-by: mgerdin, stefank

Reviewed-by: mgerdin, brutisso