From 27d00199c8b5a2d9420a3cd2e0591f4f55743dc3 Mon Sep 17 00:00:00 2001
From: "Unknown W. Brackets" <checkins@unknownbrackets.org>
Date: Tue, 23 Aug 2022 19:50:01 -0700
Subject: [PATCH] GE Debugger: Fix bad read on step at start of VRAM.

---
 GPU/GPUCommon.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/GPU/GPUCommon.cpp b/GPU/GPUCommon.cpp
index 9358a99ed9..167f7ddbf8 100644
--- a/GPU/GPUCommon.cpp
+++ b/GPU/GPUCommon.cpp
@@ -2708,7 +2708,8 @@ void GPUCommon::ResetListState(int listID, DisplayListState state) {
 
 GPUDebugOp GPUCommon::DissassembleOp(u32 pc, u32 op) {
 	char buffer[1024];
-	GeDisassembleOp(pc, op, Memory::Read_U32(pc - 4), buffer, sizeof(buffer));
+	u32 prev = Memory::IsValidAddress(pc - 4) ? Memory::ReadUnchecked_U32(pc - 4) : 0;
+	GeDisassembleOp(pc, op, prev, buffer, sizeof(buffer));
 
 	GPUDebugOp info;
 	info.pc = pc;