dpl: fix non-deterministic sort in compareNodesX with cell ID tie-breaker

Divinesoumyadip · Divinesoumyadip · commit 7b5d315aef29 · 2026-04-15T21:09:30.000Z
Signed-off-by: Divinesoumyadip &lt;soumyacode7@gmail.com&gt;
diff --git a/src/dpl/src/optimization/detailed_manager.h b/src/dpl/src/optimization/detailed_manager.h
@@ -265,7 +265,9 @@ class DetailedMgr
     // Needs cell centers.
     bool operator()(Node* p, Node* q) const
     {
-      return p->getCenterX() < q->getCenterX();
+      if (p->getCenterX() != q->getCenterX())
+        return p->getCenterX() < q->getCenterX();
+      return p->getId() < q->getId();
     }
     bool operator()(Node*& s, DbuX i) const { return s->getCenterX() < i; }
     bool operator()(DbuX i, Node*& s) const { return i < s->getCenterX(); }

Original file line number	Diff line number	Diff line change
`@@ -265,7 +265,9 @@ class DetailedMgr`
`265`	`265`	`// Needs cell centers.`
`266`	`266`	`bool operator()(Node* p, Node* q) const`
`267`	`267`	`{`
`268`		`- return p->getCenterX() < q->getCenterX();`
	`268`	`+ if (p->getCenterX() != q->getCenterX())`
	`269`	`+ return p->getCenterX() < q->getCenterX();`
	`270`	`+ return p->getId() < q->getId();`
`269`	`271`	`}`
`270`	`272`	`bool operator()(Node*& s, DbuX i) const { return s->getCenterX() < i; }`
`271`	`273`	`bool operator()(DbuX i, Node*& s) const { return i < s->getCenterX(); }`