From 234766bed904a781ba94b09a4be1165d00aeb3ae Mon Sep 17 00:00:00 2001
From: Zoltan Varga <vargaz@gmail.com>
Date: Thu, 30 Nov 2023 03:18:06 -0500
Subject: [PATCH] [mono][jit] Fix the bblock check in the box+callvirt
 optimization.

Fixes https://github.com/dotnet/runtime/issues/95347.
---
 src/mono/mono/mini/method-to-ir.c                |  5 ++---
 .../JitBlue/Runtime_95347/Runtime_95347.cs       | 16 ++++++++++++++++
 .../JitBlue/Runtime_95347/Runtime_95347.csproj   |  8 ++++++++
 3 files changed, 26 insertions(+), 3 deletions(-)
 create mode 100644 src/tests/JIT/Regression/JitBlue/Runtime_95347/Runtime_95347.cs
 create mode 100644 src/tests/JIT/Regression/JitBlue/Runtime_95347/Runtime_95347.csproj

diff --git a/src/mono/mono/mini/method-to-ir.c b/src/mono/mono/mini/method-to-ir.c
index dedc6804c3cbd..eb0ab5f4e296c 100644
--- a/src/mono/mono/mini/method-to-ir.c
+++ b/src/mono/mono/mini/method-to-ir.c
@@ -9707,12 +9707,11 @@ mono_method_to_ir (MonoCompile *cfg, MonoMethod *method, MonoBasicBlock *start_b
 			//   callvirt instance ISomeIface::Method()
 			// TO
 			//   call SomeStruct::Method()
-			guchar* callvirt_ip;
 			guint32 callvirt_proc_token;
 			if (!((cfg->compile_aot || cfg->compile_llvm) && !mono_class_is_def(klass)) && // we cannot devirtualize in AOT when using generics
 				next_ip < end &&
-				(callvirt_ip = il_read_callvirt (next_ip, end, &callvirt_proc_token)) && 
-				ip_in_bb (cfg, cfg->cbb, callvirt_ip) ) {
+				il_read_callvirt (next_ip, end, &callvirt_proc_token) &&
+				ip_in_bb (cfg, cfg->cbb, next_ip) ) {
 				MonoMethod* iface_method;
 				MonoMethodSignature* iface_method_sig;
 
diff --git a/src/tests/JIT/Regression/JitBlue/Runtime_95347/Runtime_95347.cs b/src/tests/JIT/Regression/JitBlue/Runtime_95347/Runtime_95347.cs
new file mode 100644
index 0000000000000..594d61a477362
--- /dev/null
+++ b/src/tests/JIT/Regression/JitBlue/Runtime_95347/Runtime_95347.cs
@@ -0,0 +1,16 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System;
+using Xunit;
+
+public static class Runtime_95347
+{
+    [Fact]
+    public static int Test()
+    {
+        object? n = "abcd";
+        var s = (n ?? false).ToString();
+        return (s == "abcd") ? 100 : -1;
+    }
+}
diff --git a/src/tests/JIT/Regression/JitBlue/Runtime_95347/Runtime_95347.csproj b/src/tests/JIT/Regression/JitBlue/Runtime_95347/Runtime_95347.csproj
new file mode 100644
index 0000000000000..15edd99711a1a
--- /dev/null
+++ b/src/tests/JIT/Regression/JitBlue/Runtime_95347/Runtime_95347.csproj
@@ -0,0 +1,8 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <Optimize>True</Optimize>
+  </PropertyGroup>
+  <ItemGroup>
+    <Compile Include="$(MSBuildProjectName).cs" />
+  </ItemGroup>
+</Project>
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