295   }
 296   return NULL;
 297 }
 298 
 299 bool MacroAssembler::needs_explicit_null_check(intptr_t offset) {
 300   // Exception handler checks the nmethod's implicit null checks table
 301   // only when this method returns false.
 302 #ifdef _LP64
 303   if (UseCompressedOops && Universe::narrow_oop_base() != NULL) {
 304     assert (Universe::heap() != NULL, "java heap should be initialized");
 305     // The first page after heap_base is unmapped and
 306     // the 'offset' is equal to [heap_base + offset] for
 307     // narrow oop implicit null checks.
 308     uintptr_t base = (uintptr_t)Universe::narrow_oop_base();
 309     if ((uintptr_t)offset >= base) {
 310       // Normalize offset for the next check.
 311       offset = (intptr_t)(pointer_delta((void*)offset, (void*)base, 1));
 312     }
 313   }
 314 #endif
 315   return offset < 0 || os::vm_page_size() <= offset;
 316 }

 295   }
 296   return NULL;
 297 }
 298 
 299 bool MacroAssembler::needs_explicit_null_check(intptr_t offset) {
 300   // Exception handler checks the nmethod's implicit null checks table
 301   // only when this method returns false.
 302 #ifdef _LP64
 303   if (UseCompressedOops && Universe::narrow_oop_base() != NULL) {
 304     assert (Universe::heap() != NULL, "java heap should be initialized");
 305     // The first page after heap_base is unmapped and
 306     // the 'offset' is equal to [heap_base + offset] for
 307     // narrow oop implicit null checks.
 308     uintptr_t base = (uintptr_t)Universe::narrow_oop_base();
 309     if ((uintptr_t)offset >= base) {
 310       // Normalize offset for the next check.
 311       offset = (intptr_t)(pointer_delta((void*)offset, (void*)base, 1));
 312     }
 313   }
 314 #endif
 315   return (offset < 0 && ((!UseShenandoahGC) || offset != -8)) || os::vm_page_size() <= offset;
 316 }