src/hotspot/share/gc/g1/g1CardTable.inline.hpp

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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#ifndef SHARE_GC_G1_G1CARDTABLE_INLINE_HPP
#define SHARE_GC_G1_G1CARDTABLE_INLINE_HPP

#include "gc/g1/g1CardTable.hpp"
#include "gc/g1/heapRegion.hpp"

inline uint G1CardTable::region_idx_for(CardValue* p) {
  size_t const card_idx = pointer_delta(p, _byte_map, sizeof(CardValue));
  return (uint)(card_idx >> (HeapRegion::LogOfHRGrainBytes - card_shift));
}

inline void G1CardTable::mark_clean_as_dirty(size_t card_index) {
  CardValue value = _byte_map[card_index];
  if (value == clean_card_val()) {
    _byte_map[card_index] = dirty_card_val();
  }
}

inline void G1CardTable::mark_region_dirty(size_t start_card_index, size_t num_cards) {
  assert(is_aligned(start_card_index, sizeof(size_t)), "Start card index must be aligned.");
  assert(is_aligned(num_cards, sizeof(size_t)), "Number of cards to change must be evenly divisible.");

  size_t const num_chunks = num_cards / sizeof(size_t);

  size_t* cur_word = (size_t*)&_byte_map[start_card_index];
  size_t* const end_word_map = cur_word + num_chunks;
  while (cur_word < end_word_map) {
    size_t value = *cur_word;
    if (value == WordAllClean) {
      *cur_word = WordAllDirty;
    } else if (value == WordAllDirty) {
      // do nothing.
    } else {
      // There is a mix of cards in there. Tread slowly.
      CardValue* cur = (CardValue*)cur_word;
      for (size_t i = 0; i < sizeof(size_t); i++) {
        CardValue value = *cur;
        if (value == clean_card_val()) {
          *cur = dirty_card_val();
        }
        cur++;
      }
    }
    cur_word++;
  }
}

inline void G1CardTable::mark_as_scanned(size_t start_card_index, size_t num_cards) {
  CardValue* start = &_byte_map[start_card_index];
  CardValue* const end = start + num_cards;
  while (start < end) {
    CardValue value = *start;
    assert(value == dirty_card_val(),
           "Must have been dirty %d start " PTR_FORMAT " " PTR_FORMAT, value, p2i(start), p2i(end));
    *start++ = g1_card_already_scanned;
  }
}

#endif /* SHARE_GC_G1_G1CARDTABLE_INLINE_HPP */