tap: fix missing endcaps on rows with corners

Signed-off-by: Peter Gadfort <[email protected]>

Author: gadfort

src/tap/src/tapcell.cpp

@@ -1256,8 +1256,43 @@ int Tapcell::placeEndcapEdgeVertical(const Tapcell::Edge& edge,
   for (auto* row : rows) {
     auto check_row = corners.find(row);
     if (check_row != corners.end()) {
-      // corner is already placed in this row
-      continue;
+      bool skip = false;
+      for (odb::dbInst* inst : check_row->second) {
+        switch (edge.type) {
+          case EdgeType::Right: {
+            if (inst->getBBox()->xMax() == row->getBBox().xMax()) {
+              // this edge is already placed
+              skip = true;
+            }
+            break;
+          }
+          case EdgeType::Left: {
+            if (inst->getBBox()->xMin() == row->getBBox().xMin()) {
+              // this edge is already placed
+              skip = true;
+            }
+            break;
+          }
+          case EdgeType::Top:
+          case EdgeType::Bottom:
+          case EdgeType::Unknown:
+            break;
+        }
+        if (skip) {
+          break;
+        }
+      }
+
+      if (skip) {
+        debugPrint(logger_,
+                   utl::TAP,
+                   "Endcap",
+                   2,
+                   "Skipping {} due to corners in {}",
+                   row->getName(),
+                   toString(edge.type));
+        continue;
+      }
     }
 
     const int width = edge_master->getWidth();

src/tap/test/BUILD

@@ -24,6 +24,7 @@ COMPULSORY_TESTS = [
     "endcap_autoselection_error2",
     "endcap_autoselection_error3",
     "endcap_autoselection_error4",
+    "endcap_corners",
     "gcd_asap7",
     "gcd_fakeram",
     "gcd_nangate45",

src/tap/test/CMakeLists.txt

@@ -19,6 +19,7 @@ or_integration_tests(
     endcap_autoselection_error2
     endcap_autoselection_error3
     endcap_autoselection_error4
+    endcap_corners
     gcd_asap7
     gcd_fakeram
     gcd_nangate45

src/tap/test/endcap_corners.defok

@@ -0,0 +1,9 @@
+[INFO ODB-0227] LEF file: Nangate45/Nangate45_tech.lef, created 22 layers, 27 vias
+[INFO ODB-0227] LEF file: Nangate45/Nangate45_stdcell.lef, created 135 library cells
+[INFO IFP-0005] Added 4 die polygon vertices to the list.
+[WARNING IFP-1003] Core polygon bounding box lower left (10.000, 10.000) snapped to (10.070, 11.200).
+[INFO IFP-1002] Added 63 polygon-aware rows for site FreePDK45_38x28_10R_NP_162NW_34O.
+[INFO IFP-0997] Completed polygon-aware row generation using 10 vertices
+[INFO TAP-0003] Inserted 10 endcap corners.
+[INFO TAP-0004] Inserted 952 endcaps.
+No differences found.

src/tap/test/endcap_corners.ok

@@ -0,0 +1,24 @@
+source "helpers.tcl"
+read_lef Nangate45/Nangate45_tech.lef
+read_lef Nangate45/Nangate45_stdcell.lef
+
+read_verilog endcap_corners.v
+link_design empty
+
+initialize_floorplan \
+  -die_area "0 0 0 100 100 100 100 0" \
+  -core_area "10 10 10 80 80 80 80 90 90 90 90 10 50 10 50 20 40 20 40 10 10 10" \
+  -site FreePDK45_38x28_10R_NP_162NW_34O
+
+set def_file [make_result_file endcap_corners.def]
+
+place_endcaps \
+  -corner TAPCELL_X1 \
+  -edge_corner TAPCELL_X1 \
+  -endcap TAPCELL_X1
+
+check_placement -verbose
+
+write_def $def_file
+
+diff_file endcap_corners.defok $def_file

src/tap/test/endcap_corners.tcl

@@ -0,0 +1,2 @@
+module empty ();
+endmodule