src/hotspot/share/gc/z/zObjArrayAllocator.cpp

*** 41,18 ***
    ZThreadLocalData::set_invisible_root(_thread, (oop*)&mem);
  
    // A max segment size of 64K was chosen because microbenchmarking
    // suggested that it offered a good trade-off between allocation
    // time and time-to-safepoint
!   const size_t segment_max = ZUtils::bytes_to_words(64 * K);
!   const size_t skip = arrayOopDesc::header_size(ArrayKlass::cast(_klass)->element_type());
!   size_t remaining = _word_size - skip;
  
    while (remaining > 0) {
      // Clear segment
      const size_t segment = MIN2(remaining, segment_max);
!     Copy::zero_to_words(mem + (_word_size - remaining), segment);
      remaining -= segment;
  
      if (remaining > 0) {
        // Safepoint
        ThreadBlockInVM tbivm(_thread->as_Java_thread());
--- 41,20 ---
    ZThreadLocalData::set_invisible_root(_thread, (oop*)&mem);
  
    // A max segment size of 64K was chosen because microbenchmarking
    // suggested that it offered a good trade-off between allocation
    // time and time-to-safepoint
!   const size_t segment_max = 64 * K;
!   const size_t skip = arrayOopDesc::base_offset_in_bytes(ArrayKlass::cast(_klass)->element_type());
!   size_t byte_size = _word_size * BytesPerWord;
+   size_t remaining = byte_size - skip;
  
+   char* const start = reinterpret_cast<char*>(mem);
    while (remaining > 0) {
      // Clear segment
      const size_t segment = MIN2(remaining, segment_max);
!     Copy::zero_to_bytes(start + (byte_size - remaining), segment);
      remaining -= segment;
  
      if (remaining > 0) {
        // Safepoint
        ThreadBlockInVM tbivm(_thread->as_Java_thread());