diff -r ff10f8f3a583 -r 96bd0f70ef99 src/hotspot/share/utilities/bitMap.hpp
--- a/src/hotspot/share/utilities/bitMap.hpp	Fri Nov 02 14:00:29 2018 -0700
+++ b/src/hotspot/share/utilities/bitMap.hpp	Fri Nov 02 17:51:21 2018 -0400
@@ -61,6 +61,17 @@
   bm_word_t* _map;     // First word in bitmap
   idx_t      _size;    // Size of bitmap (in bits)
 
+  // Helper for get_next_{zero,one}_bit variants.
+  // - flip designates whether searching for 1s or 0s.  Must be one of
+  //   find_{zeros,ones}_flip.
+  // - aligned_right is true if r_index is a priori on a bm_word_t boundary.
+  template<bm_word_t flip, bool aligned_right>
+  inline idx_t get_next_bit_impl(idx_t l_index, idx_t r_index) const;
+
+  // 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;
+
  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).