src/share/vm/opto/ifnode.cpp

*** 21,30 ****
--- 21,31 ----
   * questions.
   *
   */
  
  #include "precompiled.hpp"
+ #include "ci/ciTypeFlow.hpp"
  #include "memory/allocation.inline.hpp"
  #include "opto/addnode.hpp"
  #include "opto/castnode.hpp"
  #include "opto/cfgnode.hpp"
  #include "opto/connode.hpp"
*** 766,776 ****
  }
  
  // Do this If and the dominating If both branch out to an uncommon trap
  bool IfNode::has_only_uncommon_traps(ProjNode* proj, ProjNode*& success, ProjNode*& fail, PhaseIterGVN* igvn) {
    ProjNode* otherproj = proj->other_if_proj();
!   CallStaticJavaNode* dom_unc = otherproj->is_uncommon_trap_proj(Deoptimization::Reason_none);
  
    if (otherproj->outcnt() == 1 && dom_unc != NULL) {
      CallStaticJavaNode* unc = NULL;
      ProjNode* unc_proj = uncommon_trap_proj(unc);
      if (unc_proj != NULL && unc_proj->outcnt() == 1) {
--- 767,778 ----
  }
  
  // Do this If and the dominating If both branch out to an uncommon trap
  bool IfNode::has_only_uncommon_traps(ProjNode* proj, ProjNode*& success, ProjNode*& fail, PhaseIterGVN* igvn) {
    ProjNode* otherproj = proj->other_if_proj();
!   // Dominating uncommon trap must have 'Reason_unstable_if' to ensure re-execution of folded Ifs
!   CallStaticJavaNode* dom_unc = otherproj->is_uncommon_trap_proj(Deoptimization::Reason_unstable_if);
  
    if (otherproj->outcnt() == 1 && dom_unc != NULL) {
      CallStaticJavaNode* unc = NULL;
      ProjNode* unc_proj = uncommon_trap_proj(unc);
      if (unc_proj != NULL && unc_proj->outcnt() == 1) {
*** 782,797 ****
          }
          assert(r->has_phi() == NULL, "simple region shouldn't have a phi");
        } else if (dom_unc->in(0) != otherproj || unc->in(0) != unc_proj) {
          return false;
        }
        // See merge_uncommon_traps: the reason of the uncommon trap
        // will be changed and the state of the dominating If will be
        // used. Checked that we didn't apply this transformation in a
        // previous compilation and it didn't cause too many traps
!       if (!igvn->C->too_many_traps(dom_unc->jvms()->method(), dom_unc->jvms()->bci(), Deoptimization::Reason_unstable_fused_if) &&
!           !igvn->C->too_many_traps(dom_unc->jvms()->method(), dom_unc->jvms()->bci(), Deoptimization::Reason_range_check)) {
          success = unc_proj;
          fail = unc_proj->other_if_proj();
          return true;
        }
      }
--- 784,825 ----
          }
          assert(r->has_phi() == NULL, "simple region shouldn't have a phi");
        } else if (dom_unc->in(0) != otherproj || unc->in(0) != unc_proj) {
          return false;
        }
+ 
+       int dom_bci = dom_unc->jvms()->bci();
+       ciMethod* dom_method = dom_unc->jvms()->method();
+ 
+       // Get block that contains the dominating uncommon trap
+       ciTypeFlow* flow = dom_method->get_flow_analysis();
+       ciBlock* ciblk = dom_method->get_method_blocks()->block_containing(dom_bci);
+       ciTypeFlow::JsrSet* jsr = new ciTypeFlow::JsrSet(NULL);
+       ciTypeFlow::Block* block = flow->get_block_for(ciblk->index(), jsr, ciTypeFlow::no_create);
+ 
+       // Check if the bci of the dominating uncommon trap dominates the bci
+       // of the dominated uncommon trap. Otherwise we would not re-execute
+       // the dominated check after deoptimization from the merged uncommon trap.
+       int bci = unc->jvms()->bci();
+       bool dominated = false;
+       for (ciTypeFlow::SuccIter iter(block); !iter.done(); iter.next()) {
+         ciTypeFlow::Block* succ = iter.succ();
+         if (succ->start() <= bci && bci < succ->limit()) {
+           dominated = true;
+           break;
+         }
+       }
+       if (!dominated) {
+         return false;
+       }
+ 
        // See merge_uncommon_traps: the reason of the uncommon trap
        // will be changed and the state of the dominating If will be
        // used. Checked that we didn't apply this transformation in a
        // previous compilation and it didn't cause too many traps
!       if (!igvn->C->too_many_traps(dom_method, dom_bci, Deoptimization::Reason_unstable_fused_if) &&
!           !igvn->C->too_many_traps(dom_method, dom_bci, Deoptimization::Reason_range_check)) {
          success = unc_proj;
          fail = unc_proj->other_if_proj();
          return true;
        }
      }