src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp

rev 2723 : 7005808: G1: re-enable ReduceInitialCardMarks for G1
Summary: Remove the extra guard to allow G1 to use ReduceInitialCardMarks
Reviewed-by: duke

*** 1335,1350 ****
    // of this implementation depends crucially on being able to
    // answer very efficiently in constant time whether a piece of
    // storage in the heap comes from a young region or not.
    // See ReduceInitialCardMarks.
    virtual bool can_elide_tlab_store_barriers() const {
!     // 6920090: Temporarily disabled, because of lingering
!     // instabilities related to RICM with G1. In the
!     // interim, the option ReduceInitialCardMarksForG1
!     // below is left solely as a debugging device at least
!     // until 6920109 fixes the instabilities.
!     return ReduceInitialCardMarksForG1;
    }
  
    virtual bool card_mark_must_follow_store() const {
      return true;
    }
--- 1335,1345 ----
    // of this implementation depends crucially on being able to
    // answer very efficiently in constant time whether a piece of
    // storage in the heap comes from a young region or not.
    // See ReduceInitialCardMarks.
    virtual bool can_elide_tlab_store_barriers() const {
!     return true;
    }
  
    virtual bool card_mark_must_follow_store() const {
      return true;
    }
*** 1364,1375 ****
    // in the young gen: for the SATB pre-barrier, there is no
    // pre-value that needs to be remembered; for the remembered-set
    // update logging post-barrier, we don't maintain remembered set
    // information for young gen objects.
    virtual bool can_elide_initializing_store_barrier(oop new_obj) {
-     // Re 6920090, 6920109 above.
-     assert(ReduceInitialCardMarksForG1, "Else cannot be here");
      return is_in_young(new_obj);
    }
  
    // Can a compiler elide a store barrier when it writes
    // a permanent oop into the heap?  Applies when the compiler
--- 1359,1368 ----