8269771: assert(tmp == _callprojs.fallthrough_catchproj) failed: allocation control projection

Reviewed-by: rbackman, kvn

Author: Nils Eliasson

src/hotspot/share/opto/macro.cpp

@@ -965,8 +965,9 @@ void PhaseMacroExpand::process_users_of_allocation(CallNode *alloc) {
         if (ctrl_proj != NULL) {
           _igvn.replace_node(ctrl_proj, init->in(TypeFunc::Control));
 #ifdef ASSERT
+          // If the InitializeNode has no memory out, it will die, and tmp will become NULL
           Node* tmp = init->in(TypeFunc::Control);
-          assert(tmp == _callprojs.fallthrough_catchproj, "allocation control projection");
+          assert(tmp == NULL || tmp == _callprojs.fallthrough_catchproj, "allocation control projection");
 #endif
         }
         Node *mem_proj = init->proj_out_or_null(TypeFunc::Memory);

src/hotspot/share/opto/memnode.cpp

@@ -3313,7 +3313,8 @@ MemBarNode* MemBarNode::make(Compile* C, int opcode, int atp, Node* pn) {
 
 void MemBarNode::remove(PhaseIterGVN *igvn) {
   if (outcnt() != 2) {
-    return;
+    assert(Opcode() == Op_Initialize, "Only seen when there are no use of init memory");
+    assert(outcnt() == 1, "Only control then");
   }
   if (trailing_store() || trailing_load_store()) {
     MemBarNode* leading = leading_membar();
@@ -3322,8 +3323,12 @@ void MemBarNode::remove(PhaseIterGVN *igvn) {
       leading->remove(igvn);
     }
   }
-  igvn->replace_node(proj_out(TypeFunc::Memory), in(TypeFunc::Memory));
-  igvn->replace_node(proj_out(TypeFunc::Control), in(TypeFunc::Control));
+  if (proj_out_or_null(TypeFunc::Memory) != NULL) {
+    igvn->replace_node(proj_out(TypeFunc::Memory), in(TypeFunc::Memory));
+  }
+  if (proj_out_or_null(TypeFunc::Control) != NULL) {
+    igvn->replace_node(proj_out(TypeFunc::Control), in(TypeFunc::Control));
+  }
 }
 
 //------------------------------Ideal------------------------------------------