src/hotspot/cpu/x86/macroAssembler_x86.hpp

   // offset. No explicit code generation is needed if the offset is within a certain
   // range (0 <= offset <= page_size).
 
   void null_check(Register reg, int offset = -1);
   static bool needs_explicit_null_check(intptr_t offset);
+  static bool uses_implicit_null_check(void* address);
 
   // Required platform-specific helpers for Label::patch_instructions.
   // They _shadow_ the declarations in AbstractAssembler, which are undefined.
   void pd_patch_instruction(address branch, address target, const char* file, int line) {
     unsigned char op = branch[0];