src/hotspot/os_cpu/linux_aarch64/os_linux_aarch64.cpp

rev 52430 : 8213199: GC abstraction for Assembler::needs_explicit_null_check()

*** 355,368 ****
        os::Linux::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc));
        return 1;
      }
  #endif
  
-     // Handle ALL stack overflow variations here
-     if (sig == SIGSEGV) {
        address addr = (address) info->si_addr;
  
        // check if fault address is within thread stack
        if (thread->on_local_stack(addr)) {
          // stack overflow
          if (thread->in_stack_yellow_reserved_zone(addr)) {
            thread->disable_stack_yellow_reserved_zone();
--- 355,373 ----
        os::Linux::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc));
        return 1;
      }
  #endif
  
      address addr = (address) info->si_addr;
  
+     // Make sure the high order byte is sign extended, as it may be masked away by the hardware.
+     if ((uintptr_t(addr) & (uintptr_t(1) << 55)) != 0) {
+       addr = address(uintptr_t(addr) | (uintptr_t(0xFF) << 56));
+     }
+ 
+     // Handle ALL stack overflow variations here
+     if (sig == SIGSEGV) {
        // check if fault address is within thread stack
        if (thread->on_local_stack(addr)) {
          // stack overflow
          if (thread->in_stack_yellow_reserved_zone(addr)) {
            thread->disable_stack_yellow_reserved_zone();
*** 454,464 ****
            continuation_for_implicit_exception(thread,
                                                pc,
                                                SharedRuntime::
                                                IMPLICIT_DIVIDE_BY_ZERO);
        } else if (sig == SIGSEGV &&
!                !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
            // Determination of interpreter/vtable stub/compiled code null exception
            stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
        }
      } else if (thread->thread_state() == _thread_in_vm &&
                 sig == SIGBUS && /* info->si_code == BUS_OBJERR && */
--- 459,469 ----
            continuation_for_implicit_exception(thread,
                                                pc,
                                                SharedRuntime::
                                                IMPLICIT_DIVIDE_BY_ZERO);
        } else if (sig == SIGSEGV &&
!                  MacroAssembler::uses_implicit_null_check((void*)addr)) {
            // Determination of interpreter/vtable stub/compiled code null exception
            stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
        }
      } else if (thread->thread_state() == _thread_in_vm &&
                 sig == SIGBUS && /* info->si_code == BUS_OBJERR && */