src/hotspot/share/utilities/bitMap.hpp

rev 52445 : 8211926: Catastrophic size_t underflow in BitMap::*_large methods
Reviewed-by: kbarrett

*** 70,79 ****
--- 70,83 ----
  
    // Values for get_next_bit_impl flip parameter.
    static const bm_word_t find_ones_flip = 0;
    static const bm_word_t find_zeros_flip = ~(bm_word_t)0;
  
+   // Threshold for performing small range operation, even when large range
+   // operation was requested. Measured in words.
+   static const size_t small_range_words = 32;
+ 
   protected:
    // Return the position of bit within the word that contains it (e.g., if
    // bitmap words are 32 bits, return a number 0 <= n <= 31).
    static idx_t bit_in_word(idx_t bit) { return bit & (BitsPerWord - 1); }
  
*** 115,124 ****
--- 119,130 ----
    void      set_large_range_of_words   (idx_t beg, idx_t end);
    void      clear_large_range_of_words (idx_t beg, idx_t end);
  
    static void clear_range_of_words(bm_word_t* map, idx_t beg, idx_t end);
  
+   static bool is_small_range_of_words(idx_t beg_full_word, idx_t end_full_word);
+ 
    // The index of the first full word in a range.
    idx_t word_index_round_up(idx_t bit) const;
  
    // Verification.
    void verify_index(idx_t index) const NOT_DEBUG_RETURN;