From f054d9856901b12bc556f8e1918daaa34e5f1864 Mon Sep 17 00:00:00 2001
From: DreamSourceLab <support@dreamsourcelab.com>
Date: Mon, 12 Jun 2023 20:30:35 +0800
Subject: [PATCH] fix get_pre_edge error when index less than _loop_offset

---
 DSView/pv/data/logicsnapshot.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/DSView/pv/data/logicsnapshot.cpp b/DSView/pv/data/logicsnapshot.cpp
index f55fdccd..30483e42 100644
--- a/DSView/pv/data/logicsnapshot.cpp
+++ b/DSView/pv/data/logicsnapshot.cpp
@@ -834,7 +834,7 @@ bool LogicSnapshot::get_pre_edge(uint64_t &index, bool last_sample,
 
     bool flag = get_pre_edge_self(index, last_sample, min_length, sig_index);
 
-    index -= _loop_offset;
+    index = (index < _loop_offset) ? 0 : index - _loop_offset;
     _ring_sample_count -= _loop_offset;
     return flag;
 }