992   if (ShenandoahVerifyOptoBarriers && !post_parse) {
 993     ShenandoahBarrierNode::verify(Compile::current()->root());
 994   }
 995 #endif
 996 }
 997 
 998 Node* ShenandoahBarrierSetC2::ideal_node(PhaseGVN *phase, Node* n, bool can_reshape) const {
 999   if (is_shenandoah_wb_pre_call(n)) {
1000     uint cnt = ShenandoahBarrierSetC2::write_ref_field_pre_entry_Type()->domain()->cnt();
1001     if (n->req() > cnt) {
1002       Node* addp = n->in(cnt);
1003       if (has_only_shenandoah_wb_pre_uses(addp)) {
1004         n->del_req(cnt);
1005         if (can_reshape) {
1006           phase->is_IterGVN()->_worklist.push(addp);
1007         }
1008         return n;
1009       }
1010     }
1011   }





























1012   return NULL;
1013 }
1014 
1015 bool ShenandoahBarrierSetC2::has_only_shenandoah_wb_pre_uses(Node* n) {
1016   for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1017     Node* u = n->fast_out(i);
1018     if (!is_shenandoah_wb_pre_call(u)) {
1019       return false;
1020     }
1021   }
1022   return n->outcnt() > 0;
1023 }

 992   if (ShenandoahVerifyOptoBarriers && !post_parse) {
 993     ShenandoahBarrierNode::verify(Compile::current()->root());
 994   }
 995 #endif
 996 }
 997 
 998 Node* ShenandoahBarrierSetC2::ideal_node(PhaseGVN *phase, Node* n, bool can_reshape) const {
 999   if (is_shenandoah_wb_pre_call(n)) {
1000     uint cnt = ShenandoahBarrierSetC2::write_ref_field_pre_entry_Type()->domain()->cnt();
1001     if (n->req() > cnt) {
1002       Node* addp = n->in(cnt);
1003       if (has_only_shenandoah_wb_pre_uses(addp)) {
1004         n->del_req(cnt);
1005         if (can_reshape) {
1006           phase->is_IterGVN()->_worklist.push(addp);
1007         }
1008         return n;
1009       }
1010     }
1011   }
1012   if (n->Opcode() == Op_CmpP) {
1013     Node* in1 = n->in(1);
1014     Node* in2 = n->in(2);
1015     if (in1->bottom_type() == TypePtr::NULL_PTR) {
1016       in2 = step_over_gc_barrier(in2);
1017     }
1018     if (in2->bottom_type() == TypePtr::NULL_PTR) {
1019       in1 = step_over_gc_barrier(in1);
1020     }
1021     PhaseIterGVN* igvn = phase->is_IterGVN();
1022     if (in1 != n->in(1)) {
1023       if (igvn != NULL) {
1024         n->set_req_X(1, in1, igvn);
1025       } else {
1026         n->set_req(1, in1);
1027       }
1028       assert(in2 == n->in(2), "only one change");
1029       return n;
1030     }
1031     if (in2 != n->in(2)) {
1032       if (igvn != NULL) {
1033         n->set_req_X(2, in2, igvn);
1034       } else {
1035         n->set_req(2, in2);
1036       }
1037       return n;
1038     }
1039   }
1040 
1041   return NULL;
1042 }
1043 
1044 bool ShenandoahBarrierSetC2::has_only_shenandoah_wb_pre_uses(Node* n) {
1045   for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1046     Node* u = n->fast_out(i);
1047     if (!is_shenandoah_wb_pre_call(u)) {
1048       return false;
1049     }
1050   }
1051   return n->outcnt() > 0;
1052 }