--- old/src/hotspot/cpu/aarch64/gc/z/zGlobals_aarch64.cpp	2020-08-28 12:23:55.181691169 +0200
+++ new/src/hotspot/cpu/aarch64/gc/z/zGlobals_aarch64.cpp	2020-08-28 12:23:55.049690590 +0200
@@ -136,8 +136,8 @@
 //
 
 size_t ZPlatformAddressOffsetBits() {
-  const size_t min_address_offset_bits = 42; // 4TB
-  const size_t max_address_offset_bits = 44; // 16TB
+  const size_t max_address_offset_bits = ZAddressBits - 3;
+  const size_t min_address_offset_bits = max_address_offset_bits - 2;
   const size_t address_offset = round_up_power_of_2(MaxHeapSize * ZVirtualToPhysicalRatio);
   const size_t address_offset_bits = log2_intptr(address_offset);
   return clamp(address_offset_bits, min_address_offset_bits, max_address_offset_bits);