src/share/vm/opto/macro.cpp

rev 12569 : 8173147: [ctw] fails during compilation of sun.security.krb5.internal.crypto.RsaMd5DesCksumType::calculateKeyedChecksum with " graph should be schedulable"
Summary: Loads generated at uncommon trap from eliminated arraycopy have incorrect memory state
Reviewed-by: thartmann
rev 12700 : 8176506: C2: loop unswitching and unsafe accesses cause crash
Reviewed-by:

*** 2660,2670 ****
          break;
        default:
          assert(n->Opcode() == Op_LoopLimit ||
                 n->Opcode() == Op_Opaque1   ||
                 n->Opcode() == Op_Opaque2   ||
!                n->Opcode() == Op_Opaque3, "unknown node type in macro list");
        }
        assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count");
        progress = progress || success;
      }
    }
--- 2660,2671 ----
          break;
        default:
          assert(n->Opcode() == Op_LoopLimit ||
                 n->Opcode() == Op_Opaque1   ||
                 n->Opcode() == Op_Opaque2   ||
!                n->Opcode() == Op_Opaque3   ||
!                n->Opcode() == Op_Opaque4, "unknown node type in macro list");
        }
        assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count");
        progress = progress || success;
      }
    }
*** 2725,2734 ****
--- 2726,2738 ----
            repl = (cmp->in(1) == n) ? cmp->in(2) : cmp->in(1);
          }
          _igvn.replace_node(n, repl);
          success = true;
  #endif
+       } else if (n->Opcode() == Op_Opaque4) {
+         _igvn.replace_node(n, n->in(2));
+         success = true;
        }
        assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count");
        progress = progress || success;
      }
    }