From 55633b1e856c85b792f67b7742444e27224b3b1e Mon Sep 17 00:00:00 2001
From: "Emil J. Tywoniak" <emil@tywoniak.eu>
Date: Wed, 10 Dec 2025 21:35:03 +0100
Subject: [PATCH] proc_mux: copy switch src to _CMP wire

(cherry picked from commit 502ba3734b770b64f97af3241658a628744ef549)
---
 passes/proc/proc_mux.cc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/passes/proc/proc_mux.cc b/passes/proc/proc_mux.cc
index ee9685279..7752da6a9 100644
--- a/passes/proc/proc_mux.cc
+++ b/passes/proc/proc_mux.cc
@@ -217,6 +217,7 @@ struct MuxGenCtx {
 		sstr << "$procmux$" << (autoidx++);
 
 		RTLIL::Wire *cmp_wire = mod->addWire(mod->design->twines.add(std::string{sstr.str() + "_CMP"}), 0);
+		cmp_wire->transfer_src_attribute(sw);
 
 		for (auto comp : *compare)
 		{