src/hotspot/share/c1/c1_LIRGenerator.cpp

*** 1985,1995 ****
      length.set_instruction(x->length());
      length.load_item();
    }
  
    array.load_item();
!   if (index.is_constant() && can_inline_as_constant(x->index())) {
      // let it be a constant
      index.dont_load_item();
    } else {
      index.load_item();
    }
--- 1985,1996 ----
      length.set_instruction(x->length());
      length.load_item();
    }
  
    array.load_item();
!   if (index.is_constant() && can_inline_as_constant(x->index())
!       && !x->array()->maybe_flattened_array()) {
      // let it be a constant
      index.dont_load_item();
    } else {
      index.load_item();
    }
*** 2023,2052 ****
        // The range check performs the null check, so clear it out for the load
        null_check_info = NULL;
      }
    }
  
!   if (x->array()->is_flattened_array()) {
!     if (x->array()->declared_type()->is_loaded()) {
        // Find the destination address (of the NewValueTypeInstance)
        LIR_Opr obj = x->vt()->operand();
        LIRItem obj_item(x->vt(), this);
  
        access_flattened_array(true, array, index, obj_item);
        set_no_result(x);
-       return;
      } else {
!       // If the array is indeed flattened, deopt. Otherwise access it as a normal object array.
!       CodeEmitInfo* deopt_info = state_for(x, x->state_before());
!       maybe_deopt_value_array_access(array, null_check_info, deopt_info);
!     }
    }
    DecoratorSet decorators = IN_HEAP | IS_ARRAY;
-   LIR_Opr result = rlock_result(x, x->elt_type());
    access_load_at(decorators, x->elt_type(),
                   array, index.result(), result,
                   NULL, null_check_info);
  }
  
  
  void LIRGenerator::do_NullCheck(NullCheck* x) {
    if (x->can_trap()) {
--- 2024,2066 ----
        // The range check performs the null check, so clear it out for the load
        null_check_info = NULL;
      }
    }
  
!   if (x->array()->is_loaded_flattened_array()) {
      // Find the destination address (of the NewValueTypeInstance)
      LIR_Opr obj = x->vt()->operand();
      LIRItem obj_item(x->vt(), this);
  
      access_flattened_array(true, array, index, obj_item);
      set_no_result(x);
    } else {
!     LIR_Opr result = rlock_result(x, x->elt_type());
!     LoadFlattenedArrayStub* slow_path = NULL;
!     
!     if (x->array()->maybe_flattened_array()) {
!       // Check if we indeed have a flattened array
!       slow_path = new LoadFlattenedArrayStub(array.result(), index.result(), result, state_for(x));
!       LIR_Opr array_klass_reg = new_register(T_METADATA);
! 
!       __ move(new LIR_Address(array.result(), oopDesc::klass_offset_in_bytes(), T_ADDRESS), array_klass_reg);
!       LIR_Opr layout = new_register(T_INT);
!       __ move(new LIR_Address(array_klass_reg, in_bytes(Klass::layout_helper_offset()), T_INT), layout);
!       __ shift_right(layout, Klass::_lh_array_tag_shift, layout);
!       __ cmp(lir_cond_equal, layout, LIR_OprFact::intConst(Klass::_lh_array_tag_vt_value));
!       __ branch(lir_cond_equal, T_ILLEGAL, slow_path);
      }
+ 
      DecoratorSet decorators = IN_HEAP | IS_ARRAY;
      access_load_at(decorators, x->elt_type(),
                     array, index.result(), result,
                     NULL, null_check_info);
+ 
+     if (slow_path != NULL) {
+       __ branch_destination(slow_path->continuation());
+     }
+   }
  }
  
  
  void LIRGenerator::do_NullCheck(NullCheck* x) {
    if (x->can_trap()) {