src/os_cpu/aix_ppc/vm/os_aix_ppc.cpp

rev 7970 : 8074552:  SafeFetch32 and SafeFetchN do not work in error handling
Summary: handle SafeFetch faults in secondary signal handlers
Reviewed-by: dholmes
Contributed-by: Thomas Stuefe

*** 395,405 ****
          if (nm != NULL && nm->has_unsafe_access()) {
            // We don't really need a stub here! Just set the pending exeption and
            // continue at the next instruction after the faulting read. Returning
            // garbage from this read is ok.
            thread->set_pending_unsafe_access_error();
!           uc->uc_mcontext.jmp_context.iar = ((unsigned long)pc) + 4;
            return 1;
          }
        }
      }
  
--- 395,405 ----
          if (nm != NULL && nm->has_unsafe_access()) {
            // We don't really need a stub here! Just set the pending exeption and
            // continue at the next instruction after the faulting read. Returning
            // garbage from this read is ok.
            thread->set_pending_unsafe_access_error();
!           os::Aix::ucontext_set_pc(uc, pc + 4);
            return 1;
          }
        }
      }
  
*** 418,428 ****
                 sig == SIGBUS && thread->doing_unsafe_access()) {
          // We don't really need a stub here! Just set the pending exeption and
          // continue at the next instruction after the faulting read. Returning
          // garbage from this read is ok.
          thread->set_pending_unsafe_access_error();
!         uc->uc_mcontext.jmp_context.iar = ((unsigned long)pc) + 4;
          return 1;
        }
      }
  
      // Check to see if we caught the safepoint code in the
--- 418,428 ----
                 sig == SIGBUS && thread->doing_unsafe_access()) {
          // We don't really need a stub here! Just set the pending exeption and
          // continue at the next instruction after the faulting read. Returning
          // garbage from this read is ok.
          thread->set_pending_unsafe_access_error();
!         os::Aix::ucontext_set_pc(uc, pc + 4);
          return 1;
        }
      }
  
      // Check to see if we caught the safepoint code in the
*** 443,453 ****
    // One of the above code blocks ininitalized the stub, so we want to
    // delegate control to that stub.
    if (stub != NULL) {
      // Save all thread context in case we need to restore it.
      if (thread != NULL) thread->set_saved_exception_pc(pc);
!     uc->uc_mcontext.jmp_context.iar = (unsigned long)stub;
      return 1;
    }
  
  run_chained_handler:
  
--- 443,453 ----
    // One of the above code blocks ininitalized the stub, so we want to
    // delegate control to that stub.
    if (stub != NULL) {
      // Save all thread context in case we need to restore it.
      if (thread != NULL) thread->set_saved_exception_pc(pc);
!     os::Aix::ucontext_set_pc(uc, stub);
      return 1;
    }
  
  run_chained_handler: