Using the Netlist Window - 2025.2 English - UG906

Vivado Design Suite User Guide: Design Analysis and Closure Techniques (UG906)
Document ID
UG906
Release Date
2025-12-10
Version
2025.2 English

Use the Netlist window to view the design hierarchy as it exists in the netlist, processed by the synthesis tools. This window helps you explore the logical hierarchy of the design.

Figure 1. Netlist Window

Depending on your synthesis settings, the netlist hierarchy can match the original RTL, or contain no hierarchy. When run with the default settings, synthesis preserves your RTL hierarchy while optimizing logic, resulting in an optimal netlist for implementation.

Note: This results in the netlist hierarchy remaining recognizable, but the interfaces to the hierarchies can be modified. Some pins and levels of hierarchy can be missing after optimization across hierarchical boundaries. The netlist hierarchy appears as a folder tree. At each level, you see the following:
  • A Nets folder for nets at that level
  • A Leaf Cells folder if hardware primitive instances exist at that level
  • A folder for any hierarchies instantiated at that level
When you expand a hierarchy folder, you reveal the Nets, Leaf Cells, and hierarchies at that level. The icons next to the cells show information about the state of the design.

For more information, see Using the Netlist Window in the Vivado Design Suite User Guide: Using the Vivado IDE (UG893) and KEEP_HIERARCHY property and -flatten_hierarchy command switch in the Vivado Design Suite User Guide: Synthesis (UG901).

Cell Properties

Use the Cell Properties window for the selected hierarchy to view detailed information. Filter the information using the category buttons at the bottom of the window. When you select the Statistics button, you see the following:

  • Primitive usage for the full hierarchical branch, grouped in higher-level buckets
  • Number of nets crossing the hierarchy boundary
  • Clock details, including whether the clock uses global routing and the number of its loads in the current hierarchical branch
Figure 2. Cell Properties Window

If you floorplan the design, similar properties appear for the Pblock.