The-OpenROAD-Project
diff --git a/‎src/rsz/README.md‎
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diff --git a/‎src/rsz/include/rsz/Resizer.hh‎
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@@ -589,6 +589,23 @@ report_equiv_cells
 | `-match_cell_footprint` | Limit equivalent cell list to include only cells that match library cell_footprint attribute. |
 | `-all` | List all equivalent cells, ignoring sizing restrictions and cell_footprint.  Cells excluded due to these restrictions are marked with an asterisk. |
 
+### Reporting Buffers
+
+The `report_buffers` command reports all usable buffers to include for optimization.
+Usable buffers are standard cell buffers that are not clock buffers, always on buffers,
+level shifters, or buffers marked as dont-use.  VT type, cell site,
+cell footprint and leakage are also reported.
+
+```tcl
+report_buffers
+    [-filtered]
+```
+#### Options
+
+| Switch Name | Description |
+| ----- | ----- |
+| `-filtered` | Report buffers after filtering based on threshold voltage, cell footprint, drive strength and cell site.  Subset of filtered buffers are used for rebuffering. |
+
 ### Optimizing Arithmetic Modules
 
 The `replace_arith_modules` command optimizes design performance by intelligently swapping hierarchical arithmetic modules based on realistic timing models.
 
@@ -163,6 +163,73 @@ enum class MoveType
   SPLIT
 };
 
+// Voltage Threshold (VT) category identifier
+struct VTCategory
+{
+  int vt_index;
+  std::string vt_name;
+
+  // Enable use as map key
+  bool operator<(const VTCategory& other) const
+  {
+    if (vt_index != other.vt_index) {
+      return vt_index < other.vt_index;
+    }
+    return vt_name < other.vt_name;
+  }
+};
+
+// Leakage statistics for cells in a single VT category
+struct VTLeakageStats
+{
+  int cell_count = 0;
+  float total_leakage = 0.0f;
+
+  float get_average_leakage() const
+  {
+    return cell_count > 0 ? total_leakage / cell_count : 0.0f;
+  }
+
+  void add_cell_leakage(std::optional<float> cell_leak)
+  {
+    cell_count++;
+    if (cell_leak.has_value()) {
+      total_leakage += *cell_leak;
+    }
+  }
+};
+
+// Complete analysis data for a library
+struct LibraryAnalysisData
+{
+  // VT category leakage analysis
+  std::map<VTCategory, VTLeakageStats> vt_leakage_by_category;
+  // Cell footprint distribution (footprint_name -> count)
+  std::map<std::string, int> cells_by_footprint;
+  // LEF site usage distribution (site -> count)
+  std::map<odb::dbSite*, int> cells_by_site;
+  // VT categories sorted by VT type for HVT/RVT/LVT/uLVT ordering
+  std::vector<std::pair<VTCategory, VTLeakageStats>> sorted_vt_categories;
+
+  // Helper methods for common operations
+  void sort_vt_categories()
+  {
+    sorted_vt_categories.clear();
+    sorted_vt_categories.reserve(vt_leakage_by_category.size());
+    for (const auto& vt_pair : vt_leakage_by_category) {
+      sorted_vt_categories.push_back(vt_pair);
+    }
+
+    // Sort by average leakage (ascending order - least leaky to most leaky)
+    std::sort(sorted_vt_categories.begin(),
+              sorted_vt_categories.end(),
+              [](const auto& a, const auto& b) {
+                return a.second.get_average_leakage()
+                       < b.second.get_average_leakage();
+              });
+  }
+};
+
 class OdbCallBack;
 
 class Resizer : public dbStaState, public dbNetworkObserver
@@ -435,6 +502,9 @@ class Resizer : public dbStaState, public dbNetworkObserver
   void reportEquivalentCells(LibertyCell* base_cell,
                              bool match_cell_footprint,
                              bool report_all_cells);
+  void reportBuffers(bool filtered);
+  void getBufferList(LibertyCellSeq& buffer_list,
+                     LibraryAnalysisData& lib_data);
   void setDebugGraphics(std::shared_ptr<ResizerObserver> graphics);
 
   static MoveType parseMove(const std::string& s);