--- old/src/share/vm/opto/phaseX.cpp	2021-04-28 19:35:16.756454730 +0800
+++ new/src/share/vm/opto/phaseX.cpp	2021-04-28 19:35:16.635449971 +0800
@@ -1774,11 +1774,6 @@
     _worklist.push(n);          // n re-enters the hash table via the worklist
   }
 
-  // Idealize graph using DU info.  Must clone() into new-space.
-  // DU info is generally used to show profitability, progress or safety
-  // (but generally not needed for correctness).
-  Node *nn = n->Ideal_DU_postCCP(this);
-
   // TEMPORARY fix to ensure that 2nd GVN pass eliminates NULL checks
   switch( n->Opcode() ) {
   case Op_FastLock:      // Revisit FastLocks for lock coarsening
@@ -1795,13 +1790,6 @@
   default:
     break;
   }
-  if( nn ) {
-    _worklist.push(n);
-    // Put users of 'n' onto worklist for second igvn transform
-    add_users_to_worklist(n);
-    return nn;
-  }
-
   return  n;
 }