diff -rauN jdk10u-jdk-10.0.2+13/src/hotspot/share/c1/c1_Instruction.hpp jdk10u-jdk-10.0.2+13-c1-patch/src/hotspot/share/c1/c1_Instruction.hpp
--- jdk10u-jdk-10.0.2+13/src/hotspot/share/c1/c1_Instruction.hpp	2018-06-24 16:07:06.000000000 +0200
+++ jdk10u-jdk-10.0.2+13-c1-patch/src/hotspot/share/c1/c1_Instruction.hpp	2021-05-17 17:31:40.472148317 +0200
@@ -303,7 +303,6 @@
   XHandlers*   _exception_handlers;              // Flat list of exception handlers covering this instruction
 
   friend class UseCountComputer;
-  friend class BlockBegin;
 
   void update_exception_state(ValueStack* state);
 
@@ -349,7 +348,6 @@
   void* operator new(size_t size) throw() {
     Compilation* c = Compilation::current();
     void* res = c->arena()->Amalloc(size);
-    ((Instruction*)res)->_id = c->get_next_id();
     return res;
   }
 
@@ -410,7 +408,8 @@
 
   // creation
   Instruction(ValueType* type, ValueStack* state_before = NULL, bool type_is_constant = false)
-  : _use_count(0)
+  : _id(Compilation::current()->get_next_id())
+  , _use_count(0)
 #ifndef PRODUCT
   , _printable_bci(-99)
 #endif
@@ -1648,8 +1647,6 @@
    void* operator new(size_t size) throw() {
     Compilation* c = Compilation::current();
     void* res = c->arena()->Amalloc(size);
-    ((BlockBegin*)res)->_id = c->get_next_id();
-    ((BlockBegin*)res)->_block_id = c->get_next_block_id();
     return res;
   }
 
@@ -1661,6 +1658,7 @@
   // creation
   BlockBegin(int bci)
   : StateSplit(illegalType)
+  , _block_id(Compilation::current()->get_next_block_id())
   , _bci(bci)
   , _depth_first_number(-1)
   , _linear_scan_number(-1)
diff -rauN jdk10u-jdk-10.0.2+13/src/hotspot/share/c1/c1_ValueMap.cpp jdk10u-jdk-10.0.2+13-c1-patch/src/hotspot/share/c1/c1_ValueMap.cpp
--- jdk10u-jdk-10.0.2+13/src/hotspot/share/c1/c1_ValueMap.cpp	2018-06-24 16:07:06.000000000 +0200
+++ jdk10u-jdk-10.0.2+13-c1-patch/src/hotspot/share/c1/c1_ValueMap.cpp	2021-05-17 17:32:03.702163251 +0200
@@ -488,6 +488,7 @@
   : _current_map(NULL)
   , _value_maps(ir->linear_scan_order()->length(), ir->linear_scan_order()->length(), NULL)
   , _compilation(ir->compilation())
+  , _has_substitutions(false)
 {
   TRACE_VALUE_NUMBERING(tty->print_cr("****** start of global value numbering"));