pdn: ripup incomplete via stacks

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

Author: gadfort

src/pdn/src/via.cpp

@@ -3024,6 +3024,48 @@ void Via::writeToDb(odb::dbSWire* wire,
   }
   ripup_shapes.insert(ripup_vias_middle.begin(), ripup_vias_middle.end());
 
+  if (!ripup_shapes.empty()) {
+    // Check if via stack continuity will be broken
+
+    // Collect remaining shapes
+    std::set<odb::dbTechLayer*> layers;
+    for (const auto& viashapes : {shapes.bottom, shapes.middle, shapes.top}) {
+      for (const auto& [rect, box] : viashapes) {
+        if (ripup_shapes.find(box) == ripup_shapes.end()) {
+          if (box->isVia()) {
+            if (auto* via = box->getBlockVia()) {
+              for (auto* viabox : via->getBoxes()) {
+                layers.insert(viabox->getTechLayer());
+              }
+            } else if (auto* via = box->getTechVia()) {
+              for (auto* viabox : via->getBoxes()) {
+                layers.insert(viabox->getTechLayer());
+              }
+            }
+          } else {
+            layers.insert(box->getTechLayer());
+          }
+        }
+      }
+    }
+
+    bool broken = false;
+    for (auto* layer : connect_->getAllLayers()) {
+      if (layers.find(layer) == layers.end()) {
+        // stack is broken
+        broken = true;
+      }
+    }
+
+    if (broken) {
+      for (const auto& viashapes : {shapes.bottom, shapes.middle, shapes.top}) {
+        for (const auto& [rect, box] : viashapes) {
+          ripup_shapes.insert(box);
+        }
+      }
+    }
+  }
+
   if (!ripup_shapes.empty()) {
     const TechLayer tech_layer(lower_->getLayer());
     int x = 0;

src/pdn/test/core_grid_with_single_edge_pins.defok

@@ -1881,7 +1881,6 @@ SPECIALNETS 2 ;
       NEW metal3 0 + SHAPE STRIPE ( 164000 5600 ) via3_4_960_340_1_3_320_320
       NEW metal2 0 + SHAPE STRIPE ( 164000 5600 ) via2_3_960_340_1_3_320_320
       NEW metal1 0 + SHAPE STRIPE ( 164000 5600 ) via1_2_960_340_1_3_300_300
-      NEW metal3 0 + SHAPE STRIPE ( 164000 10 ) via3_4_960_340_1_3_320_320
       NEW metal3 0 + SHAPE STRIPE ( 124000 201600 ) via3_4_960_340_1_3_320_320
       NEW metal2 0 + SHAPE STRIPE ( 124000 201600 ) via2_3_960_340_1_3_320_320
       NEW metal1 0 + SHAPE STRIPE ( 124000 201600 ) via1_2_960_340_1_3_300_300
@@ -1990,7 +1989,6 @@ SPECIALNETS 2 ;
       NEW metal3 0 + SHAPE STRIPE ( 124000 5600 ) via3_4_960_340_1_3_320_320
       NEW metal2 0 + SHAPE STRIPE ( 124000 5600 ) via2_3_960_340_1_3_320_320
       NEW metal1 0 + SHAPE STRIPE ( 124000 5600 ) via1_2_960_340_1_3_300_300
-      NEW metal3 0 + SHAPE STRIPE ( 124000 10 ) via3_4_960_340_1_3_320_320
       NEW metal3 0 + SHAPE STRIPE ( 84000 201600 ) via3_4_960_340_1_3_320_320
       NEW metal2 0 + SHAPE STRIPE ( 84000 201600 ) via2_3_960_340_1_3_320_320
       NEW metal1 0 + SHAPE STRIPE ( 84000 201600 ) via1_2_960_340_1_3_300_300
@@ -2099,7 +2097,6 @@ SPECIALNETS 2 ;
       NEW metal3 0 + SHAPE STRIPE ( 84000 5600 ) via3_4_960_340_1_3_320_320
       NEW metal2 0 + SHAPE STRIPE ( 84000 5600 ) via2_3_960_340_1_3_320_320
       NEW metal1 0 + SHAPE STRIPE ( 84000 5600 ) via1_2_960_340_1_3_300_300
-      NEW metal3 0 + SHAPE STRIPE ( 84000 10 ) via3_4_960_340_1_3_320_320
       NEW metal3 0 + SHAPE STRIPE ( 44000 201600 ) via3_4_960_340_1_3_320_320
       NEW metal2 0 + SHAPE STRIPE ( 44000 201600 ) via2_3_960_340_1_3_320_320
       NEW metal1 0 + SHAPE STRIPE ( 44000 201600 ) via1_2_960_340_1_3_300_300
@@ -2312,8 +2309,7 @@ SPECIALNETS 2 ;
       NEW metal1 0 + SHAPE STRIPE ( 4000 11200 ) via1_2_960_340_1_3_300_300
       NEW metal3 0 + SHAPE STRIPE ( 4000 5600 ) via3_4_960_340_1_3_320_320
       NEW metal2 0 + SHAPE STRIPE ( 4000 5600 ) via2_3_960_340_1_3_320_320
-      NEW metal1 0 + SHAPE STRIPE ( 4000 5600 ) via1_2_960_340_1_3_300_300
-      NEW metal3 0 + SHAPE STRIPE ( 4000 10 ) via3_4_960_340_1_3_320_320 ;
+      NEW metal1 0 + SHAPE STRIPE ( 4000 5600 ) via1_2_960_340_1_3_300_300 ;
 END SPECIALNETS
 NETS 385 ;
     - _000_ ( _324_ ZN ) ( _576_ D ) + USE SIGNAL ;

src/pdn/test/core_grid_with_single_edge_pins.ok

@@ -5,8 +5,8 @@
 [INFO ODB-0133]     Created 385 nets and 1110 connections.
 [INFO IFP-0001] Added 72 rows of 527 site FreePDK45_38x28_10R_NP_162NW_34O.
 [INFO PDN-0001] Inserting grid: Core
-[WARNING PDN-0195] Removing 2 via(s) between metal1 and metal4 at (2.0000 um, 0.0050 um) for VSS
-[WARNING PDN-0195] Removing 2 via(s) between metal1 and metal4 at (42.0000 um, 0.0050 um) for VSS
-[WARNING PDN-0195] Removing 2 via(s) between metal1 and metal4 at (62.0000 um, 0.0050 um) for VSS
-[WARNING PDN-0195] Removing 2 via(s) between metal1 and metal4 at (82.0000 um, 0.0050 um) for VSS
+[WARNING PDN-0195] Removing 3 via(s) between metal1 and metal4 at (2.0000 um, 0.0050 um) for VSS
+[WARNING PDN-0195] Removing 3 via(s) between metal1 and metal4 at (42.0000 um, 0.0050 um) for VSS
+[WARNING PDN-0195] Removing 3 via(s) between metal1 and metal4 at (62.0000 um, 0.0050 um) for VSS
+[WARNING PDN-0195] Removing 3 via(s) between metal1 and metal4 at (82.0000 um, 0.0050 um) for VSS
 No differences found.