src/share/vm/opto/cfgnode.cpp

*** 34,43 ****
--- 34,47 ----
  #include "opto/mulnode.hpp"
  #include "opto/phaseX.hpp"
  #include "opto/regmask.hpp"
  #include "opto/runtime.hpp"
  #include "opto/subnode.hpp"
+ #if INCLUDE_ALL_GCS
+ #include "gc_implementation/shenandoah/c2/shenandoahBarrierSetC2.hpp"
+ #include "gc_implementation/shenandoah/c2/shenandoahSupport.hpp"
+ #endif
  
  // Portions of code courtesy of Clifford Click
  
  // Optimization - Graph Style
  
*** 586,595 ****
--- 590,602 ----
              assert( n->req() == 2 &&  n->in(1) != NULL, "Only one data input expected" );
              in = n->in(1);               // replaced by unique input
              if( n->as_Phi()->is_unsafe_data_reference(in) )
                in = phase->C->top();      // replaced by top
            }
+           if (n->outcnt() == 0) {
+             in = phase->C->top();
+           }
            igvn->replace_node(n, in);
          }
          else if( n->is_Region() ) { // Update all incoming edges
            assert( !igvn->eqv(n, this), "Must be removed from DefUse edges");
            uint uses_found = 0;
*** 1626,1636 ****
        if (n != top) {           // Not already top?
          PhaseIterGVN *igvn = phase->is_IterGVN();
          if (can_reshape && igvn != NULL) {
            igvn->_worklist.push(r);
          }
!         set_req(j, top);        // Nuke it down
          progress = this;        // Record progress
        }
      }
    }
  
--- 1633,1648 ----
        if (n != top) {           // Not already top?
          PhaseIterGVN *igvn = phase->is_IterGVN();
          if (can_reshape && igvn != NULL) {
            igvn->_worklist.push(r);
          }
!         // Nuke it down
!         if (can_reshape) {
!           set_req_X(j, top, igvn);
!         } else {
!           set_req(j, top);
!         }
          progress = this;        // Record progress
        }
      }
    }