From: whitequark <cz@m-labs.hk>
Date: Fri, 14 Dec 2018 13:25:51 +0000 (+0000)
Subject: back.pysim: skip VCD signal population if VCD is not requested.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=dc3fe7067b32685f01782c8c0770ef2fe81e8a09;p=nmigen.git

back.pysim: skip VCD signal population if VCD is not requested.
---

diff --git a/nmigen/back/pysim.py b/nmigen/back/pysim.py
index 18318b9..88cd7a3 100644
--- a/nmigen/back/pysim.py
+++ b/nmigen/back/pysim.py
@@ -281,6 +281,9 @@ class Simulator:
                     normalize(signal.reset, signal.shape())
                 self._state.curr_dirty.add(signal)
 
+                if not self._vcd_writer:
+                    continue
+
                 if signal not in self._vcd_signals:
                     self._vcd_signals[signal] = set()