This option is not available if Quartus II Integrated Synthesis is being used. In addition, you can set the Never Allow setting in the logic option for nodes or entities so that the Quartus II software does not unmap certain logic elements in the current design.
Directs the Quartus II software to duplicate logic elements (LUTs only) and resynthesize the LUTs during fitting to increase performance. This option is often used with the Automatically duplicate logic elements option described above.
08/12/2005 · Black Box Attribute in Quartus II
The Quartus II software cannot perform these netlist optimizations on a back-annotated design. In addition, if you use one or both of these netlist optimizations on a design, and then back-annotate the design, you must generate a that indicates the duplicated LUTs that the Quartus II software generated and/or resynthesized while fitting the design.
Block Design Naming logic option - …
Directs the Quartus II software to duplicate logic elements during fitting to increase performance. Only LUTs are duplicated by this option's algorithm; however, the Quartus II software does not duplicate LUTs that are packed with virtual I/Os. This option is often used with the Perform logic element level LUT resynthesis option described below.