From a6b89b0727c1d77c4d50d0850b8f21f35966f653 Mon Sep 17 00:00:00 2001
From: ShiboSoftwareDev <shibosoftwaredev@gmail.com>
Date: Tue, 4 Aug 2026 13:30:30 +0200
Subject: [PATCH] fix: duplicate congested ports per distinct net

---
 lib/DuplicateCongestedPortSolver.ts           | 19 +++++++++++++------
 .../duplicate-congested-port-solver.test.ts   | 16 ++++++++++++++++
 2 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/lib/DuplicateCongestedPortSolver.ts b/lib/DuplicateCongestedPortSolver.ts
index e9f0f08..72cb74b 100644
--- a/lib/DuplicateCongestedPortSolver.ts
+++ b/lib/DuplicateCongestedPortSolver.ts
@@ -326,7 +326,7 @@ export class DuplicateCongestedPortSolver extends BaseSolver {
     const { topology, problem } = loadSerializedHyperGraph(
       this.serializedHyperGraph,
     )
-    const portUseCounts = new Map<string, number>()
+    const portNetIds = new Map<string, Set<number>>()
 
     for (let routeId = 0; routeId < problem.routeCount; routeId++) {
       const routeProblem = createSingleRouteProblem(problem, routeId)
@@ -347,14 +347,21 @@ export class DuplicateCongestedPortSolver extends BaseSolver {
 
       for (const portId of getUsedPortIdsForSolvedRoute(routeSolver)) {
         const serializedPortId = getSerializedPortId(topology, portId)
-        portUseCounts.set(
-          serializedPortId,
-          (portUseCounts.get(serializedPortId) ?? 0) + 1,
-        )
+        let netIds = portNetIds.get(serializedPortId)
+        if (!netIds) {
+          netIds = new Set()
+          portNetIds.set(serializedPortId, netIds)
+        }
+        netIds.add(problem.routeNet[routeId]!)
       }
     }
 
-    return portUseCounts
+    return new Map(
+      [...portNetIds].map(([serializedPortId, netIds]) => [
+        serializedPortId,
+        netIds.size,
+      ]),
+    )
   }
 
   private duplicateCongestedPorts(
diff --git a/tests/solver/duplicate-congested-port-solver.test.ts b/tests/solver/duplicate-congested-port-solver.test.ts
index ec2c1e5..4b21465 100644
--- a/tests/solver/duplicate-congested-port-solver.test.ts
+++ b/tests/solver/duplicate-congested-port-solver.test.ts
@@ -198,3 +198,19 @@ test("duplicate congested port solver duplicates independently reused ports in l
       .every((region) => region.pointIds.includes("shared-choke::dup1")),
   ).toBe(true)
 })
+
+test("duplicate congested port solver shares a port between routes on the same net", () => {
+  const fixture = createDuplicatePortFixture()
+  fixture.connections![1]!.mutuallyConnectedNetworkId = "net-a"
+  const solver = new DuplicateCongestedPortSolver(fixture)
+
+  solver.solve()
+
+  expect(solver.solved).toBe(true)
+  expect(solver.failed).toBe(false)
+  expect(solver.report.portUseCounts["shared-choke"]).toBe(1)
+  expect(solver.report.duplicatedPorts).not.toContainEqual(
+    expect.objectContaining({ sourcePortId: "shared-choke" }),
+  )
+  expect(solver.getOutput().ports).toHaveLength(fixture.ports.length)
+})