944   _dwl_mean = double(MIN2(ParallelOldDeadWoodLimiterMean, max)) / 100.0;
 945   _dwl_std_dev = double(MIN2(ParallelOldDeadWoodLimiterStdDev, max)) / 100.0;
 946   _dwl_first_term = 1.0 / (sqrt(2.0 * M_PI) * _dwl_std_dev);
 947   DEBUG_ONLY(_dwl_initialized = true;)
 948   _dwl_adjustment = normal_distribution(1.0);
 949 }
 950 
 951 void
 952 PSParallelCompact::clear_data_covering_space(SpaceId id)
 953 {
 954   // At this point, top is the value before GC, new_top() is the value that will
 955   // be set at the end of GC.  The marking bitmap is cleared to top; nothing
 956   // should be marked above top.  The summary data is cleared to the larger of
 957   // top & new_top.
 958   MutableSpace* const space = _space_info[id].space();
 959   HeapWord* const bot = space->bottom();
 960   HeapWord* const top = space->top();
 961   HeapWord* const max_top = MAX2(top, _space_info[id].new_top());
 962 
 963   const idx_t beg_bit = _mark_bitmap.addr_to_bit(bot);
 964   const idx_t end_bit = BitMap::word_align_up(_mark_bitmap.addr_to_bit(top));
 965   _mark_bitmap.clear_range(beg_bit, end_bit);
 966 
 967   const size_t beg_region = _summary_data.addr_to_region_idx(bot);
 968   const size_t end_region =
 969     _summary_data.addr_to_region_idx(_summary_data.region_align_up(max_top));
 970   _summary_data.clear_range(beg_region, end_region);
 971 
 972   // Clear the data used to 'split' regions.
 973   SplitInfo& split_info = _space_info[id].split_info();
 974   if (split_info.is_valid()) {
 975     split_info.clear();
 976   }
 977   DEBUG_ONLY(split_info.verify_clear();)
 978 }
 979 
 980 void PSParallelCompact::pre_compact()
 981 {
 982   // Update the from & to space pointers in space_info, since they are swapped
 983   // at each young gen gc.  Do the update unconditionally (even though a
 984   // promotion failure does not swap spaces) because an unknown number of young

2832       }
2833       cm->update_contents(oop(addr));
2834       assert(oopDesc::is_oop_or_null(oop(addr)), "Expected an oop or NULL at " PTR_FORMAT, p2i(oop(addr)));
2835     }
2836   }
2837 }
2838 
2839 // Skip over count live words starting from beg, and return the address of the
2840 // next live word.  Unless marked, the word corresponding to beg is assumed to
2841 // be dead.  Callers must either ensure beg does not correspond to the middle of
2842 // an object, or account for those live words in some other way.  Callers must
2843 // also ensure that there are enough live words in the range [beg, end) to skip.
2844 HeapWord*
2845 PSParallelCompact::skip_live_words(HeapWord* beg, HeapWord* end, size_t count)
2846 {
2847   assert(count > 0, "sanity");
2848 
2849   ParMarkBitMap* m = mark_bitmap();
2850   idx_t bits_to_skip = m->words_to_bits(count);
2851   idx_t cur_beg = m->addr_to_bit(beg);
2852   const idx_t search_end = BitMap::word_align_up(m->addr_to_bit(end));
2853 
2854   do {
2855     cur_beg = m->find_obj_beg(cur_beg, search_end);
2856     idx_t cur_end = m->find_obj_end(cur_beg, search_end);
2857     const size_t obj_bits = cur_end - cur_beg + 1;
2858     if (obj_bits > bits_to_skip) {
2859       return m->bit_to_addr(cur_beg + bits_to_skip);
2860     }
2861     bits_to_skip -= obj_bits;
2862     cur_beg = cur_end + 1;
2863   } while (bits_to_skip > 0);
2864 
2865   // Skipping the desired number of words landed just past the end of an object.
2866   // Find the start of the next object.
2867   cur_beg = m->find_obj_beg(cur_beg, search_end);
2868   assert(cur_beg < m->addr_to_bit(end), "not enough live words to skip");
2869   return m->bit_to_addr(cur_beg);
2870 }
2871 
2872 HeapWord* PSParallelCompact::first_src_addr(HeapWord* const dest_addr,

 944   _dwl_mean = double(MIN2(ParallelOldDeadWoodLimiterMean, max)) / 100.0;
 945   _dwl_std_dev = double(MIN2(ParallelOldDeadWoodLimiterStdDev, max)) / 100.0;
 946   _dwl_first_term = 1.0 / (sqrt(2.0 * M_PI) * _dwl_std_dev);
 947   DEBUG_ONLY(_dwl_initialized = true;)
 948   _dwl_adjustment = normal_distribution(1.0);
 949 }
 950 
 951 void
 952 PSParallelCompact::clear_data_covering_space(SpaceId id)
 953 {
 954   // At this point, top is the value before GC, new_top() is the value that will
 955   // be set at the end of GC.  The marking bitmap is cleared to top; nothing
 956   // should be marked above top.  The summary data is cleared to the larger of
 957   // top & new_top.
 958   MutableSpace* const space = _space_info[id].space();
 959   HeapWord* const bot = space->bottom();
 960   HeapWord* const top = space->top();
 961   HeapWord* const max_top = MAX2(top, _space_info[id].new_top());
 962 
 963   const idx_t beg_bit = _mark_bitmap.addr_to_bit(bot);
 964   const idx_t end_bit = _mark_bitmap.align_range_end(_mark_bitmap.addr_to_bit(top));
 965   _mark_bitmap.clear_range(beg_bit, end_bit);
 966 
 967   const size_t beg_region = _summary_data.addr_to_region_idx(bot);
 968   const size_t end_region =
 969     _summary_data.addr_to_region_idx(_summary_data.region_align_up(max_top));
 970   _summary_data.clear_range(beg_region, end_region);
 971 
 972   // Clear the data used to 'split' regions.
 973   SplitInfo& split_info = _space_info[id].split_info();
 974   if (split_info.is_valid()) {
 975     split_info.clear();
 976   }
 977   DEBUG_ONLY(split_info.verify_clear();)
 978 }
 979 
 980 void PSParallelCompact::pre_compact()
 981 {
 982   // Update the from & to space pointers in space_info, since they are swapped
 983   // at each young gen gc.  Do the update unconditionally (even though a
 984   // promotion failure does not swap spaces) because an unknown number of young

2832       }
2833       cm->update_contents(oop(addr));
2834       assert(oopDesc::is_oop_or_null(oop(addr)), "Expected an oop or NULL at " PTR_FORMAT, p2i(oop(addr)));
2835     }
2836   }
2837 }
2838 
2839 // Skip over count live words starting from beg, and return the address of the
2840 // next live word.  Unless marked, the word corresponding to beg is assumed to
2841 // be dead.  Callers must either ensure beg does not correspond to the middle of
2842 // an object, or account for those live words in some other way.  Callers must
2843 // also ensure that there are enough live words in the range [beg, end) to skip.
2844 HeapWord*
2845 PSParallelCompact::skip_live_words(HeapWord* beg, HeapWord* end, size_t count)
2846 {
2847   assert(count > 0, "sanity");
2848 
2849   ParMarkBitMap* m = mark_bitmap();
2850   idx_t bits_to_skip = m->words_to_bits(count);
2851   idx_t cur_beg = m->addr_to_bit(beg);
2852   const idx_t search_end = m->align_range_end(m->addr_to_bit(end));
2853 
2854   do {
2855     cur_beg = m->find_obj_beg(cur_beg, search_end);
2856     idx_t cur_end = m->find_obj_end(cur_beg, search_end);
2857     const size_t obj_bits = cur_end - cur_beg + 1;
2858     if (obj_bits > bits_to_skip) {
2859       return m->bit_to_addr(cur_beg + bits_to_skip);
2860     }
2861     bits_to_skip -= obj_bits;
2862     cur_beg = cur_end + 1;
2863   } while (bits_to_skip > 0);
2864 
2865   // Skipping the desired number of words landed just past the end of an object.
2866   // Find the start of the next object.
2867   cur_beg = m->find_obj_beg(cur_beg, search_end);
2868   assert(cur_beg < m->addr_to_bit(end), "not enough live words to skip");
2869   return m->bit_to_addr(cur_beg);
2870 }
2871 
2872 HeapWord* PSParallelCompact::first_src_addr(HeapWord* const dest_addr,