src/hotspot/share/opto/buildOopMap.cpp

@@ -239,11 +239,12 @@
      Node *def = _defs[reg];     // Get reaching def
      assert( def, "since live better have reaching def" );
  
      // Classify the reaching def as oop, derived, callee-save, dead, or other
      const Type *t = def->bottom_type();
-     if( t->isa_oop_ptr() ) {    // Oop or derived?
+     if( t->isa_oop_ptr() || // Oop or derived?
+        (C->do_stack_allocation() && t->isa_rawptr() && def->is_BoxLock())) {  // consider stack oops too
        assert( !OptoReg::is_valid(_callees[reg]), "oop can't be callee save" );
  #ifdef _LP64
        // 64-bit pointers record oop-ishness on 2 aligned adjacent registers.
        // Make sure both are record from the same reaching def, but do not
        // put both into the oopmap.