*** old/src/share/vm/opto/parse2.cpp	Thu Jan  7 16:01:57 2010
--- new/src/share/vm/opto/parse2.cpp	Thu Jan  7 16:01:57 2010

*** 276,285 ****
--- 276,290 ----
    int len          = hi_index - lo_index + 1;
  
    if (len < 1) {
      // If this is a backward branch, add safepoint
      maybe_add_safepoint(default_dest);
+     if(should_add_predicate(default_dest)){
+       _sp += 1; //set original stack for use by uncommon_trap
+       add_predicate();
+       _sp -= 1;
+     }
      merge(default_dest);
      return;
    }
  
    // generate decision tree, using trichotomy when possible

*** 322,331 ****
--- 327,341 ----
    int default_dest = iter().get_dest_table(0);
    int len          = iter().get_int_table(1);
  
    if (len < 1) {    // If this is a backward branch, add safepoint
      maybe_add_safepoint(default_dest);
+     if(should_add_predicate(default_dest)){
+       _sp += 1; //set original stack for use by uncommon_trap
+       add_predicate();
+       _sp -= 1;
+     }
      merge(default_dest);
      return;
    }
  
    // generate decision tree, using trichotomy when possible

*** 729,738 ****
--- 739,751 ----
  
    // Effect on jsr on stack
    push(_gvn.makecon(ret_addr));
  
    // Flow to the jsr.
+   if(should_add_predicate(jsr_bci)){
+     add_predicate();
+   }
    merge(jsr_bci);
  }
  
  // Handle ret bytecode
  void Parse::do_ret() {

*** 879,889 ****
--- 892,902 ----
    return prob < PROB_MIN;
  }
  
  //-------------------------------repush_if_args--------------------------------
  // Push arguments of an "if" bytecode back onto the stack by adjusting _sp.
! inline void Parse::repush_if_args() {
! inline int Parse::repush_if_args() {
  #ifndef PRODUCT
    if (PrintOpto && WizardMode) {
      tty->print("defending against excessive implicit null exceptions on %s @%d in ",
                 Bytecodes::name(iter().cur_bc()), iter().cur_bci());
      method()->print_name(); tty->cr();

*** 893,902 ****
--- 906,916 ----
    assert(bc_depth == 1 || bc_depth == 2, "only two kinds of branches");
    DEBUG_ONLY(sync_jvms());   // argument(n) requires a synced jvms
    assert(argument(0) != NULL, "must exist");
    assert(bc_depth == 1 || argument(1) != NULL, "two must exist");
    _sp += bc_depth;
+   return bc_depth;
  }
  
  //----------------------------------do_ifnull----------------------------------
  void Parse::do_ifnull(BoolTest::mask btest, Node *c) {
    int target_bci = iter().get_dest();

*** 952,965 ****
--- 966,985 ----
        }
      } else {                    // Path is live.
        // Update method data
        profile_taken_branch(target_bci);
        adjust_map_after_if(btest, c, prob, branch_block, next_block);
!       if (!stopped()) {
+         if(should_add_predicate(target_bci)){//add a predicate if it branches to a loop
+           int nargs = repush_if_args();//set original stack for uncommon_trap
+           add_predicate();
+           _sp -= nargs;
+         }
          merge(target_bci);
        }
      }
+   }
  
    // False branch
    Node* iffalse = _gvn.transform( new (C, 1) IfFalseNode(iff) );
    set_control(iffalse);
  

*** 1074,1087 ****
--- 1094,1113 ----
        }
      } else {
        // Update method data
        profile_taken_branch(target_bci);
        adjust_map_after_if(taken_btest, c, prob, branch_block, next_block);
!       if (!stopped()) {
+         if(should_add_predicate(target_bci)){//add a predicate if it branches to a loop
+           int nargs = repush_if_args(); //set original stack for the uncommon_trap
+           add_predicate();
+           _sp -= nargs;
+         }
          merge(target_bci);
        }
      }
+   }
  
    untaken_branch = _gvn.transform(untaken_branch);
    set_control(untaken_branch);
  
    // Branch not taken.

*** 2078,2087 ****
--- 2104,2117 ----
      maybe_add_safepoint(target_bci);
  
      // Update method data
      profile_taken_branch(target_bci);
  
+     //Add loop predicate if it goes to a loop
+     if(should_add_predicate(target_bci)){
+       add_predicate();
+     }
      // Merge the current control into the target basic block
      merge(target_bci);
  
      // See if we can get some profile data and hand it off to the next block
      Block *target_block = block()->successor_for_bci(target_bci);