From f077de01ff71242012de8b45a08ff504944fd460 Mon Sep 17 00:00:00 2001
From: Andy Ayers <andya@microsoft.com>
Date: Tue, 25 Apr 2023 16:50:22 -0700
Subject: [PATCH] JIT: add ssa accounting to morph's div opts (#85332)

RBO triggered a morph opt that cloned an SSA local, throwing off the SSA
accounting. Fix by invoking the accounting helper after the morph expansion.

Closes #85226.
---
 src/coreclr/jit/morph.cpp                     |  2 ++
 .../JitBlue/Runtime_85226/Runtime_85226.cs    | 36 +++++++++++++++++++
 .../Runtime_85226/Runtime_85226.csproj        |  8 +++++
 3 files changed, 46 insertions(+)
 create mode 100644 src/tests/JIT/Regression/JitBlue/Runtime_85226/Runtime_85226.cs
 create mode 100644 src/tests/JIT/Regression/JitBlue/Runtime_85226/Runtime_85226.csproj

diff --git a/src/coreclr/jit/morph.cpp b/src/coreclr/jit/morph.cpp
index ea5838af587..ffe382e1952 100644
--- a/src/coreclr/jit/morph.cpp
+++ b/src/coreclr/jit/morph.cpp
@@ -12152,6 +12152,8 @@ GenTree* Compiler::fgMorphModToSubMulDiv(GenTreeOp* tree)
     result->gtDebugFlags |= GTF_DEBUG_NODE_MORPHED;
 #endif
 
+    optRecordSsaUses(result, compCurBB);
+
     div->CheckDivideByConstOptimized(this);
 
     return result;
diff --git a/src/tests/JIT/Regression/JitBlue/Runtime_85226/Runtime_85226.cs b/src/tests/JIT/Regression/JitBlue/Runtime_85226/Runtime_85226.cs
new file mode 100644
index 00000000000..7aadc68a28d
--- /dev/null
+++ b/src/tests/JIT/Regression/JitBlue/Runtime_85226/Runtime_85226.cs
@@ -0,0 +1,36 @@
+// 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;
+
+// Generated by Fuzzlyn v1.5 on 2023-04-23 17:14:26
+// Run on X64 Windows
+// Seed: 11244895947685014560
+// Reduced from 7.8 KiB to 0.3 KiB in 00:00:41
+// Hits JIT assert in Release:
+// Assertion failed '!"SSA check failures"' in 'Program:M1()' during 'Redundant branch opts' (IL size 29; hash 0xaf510bb6; FullOpts)
+// 
+//     File: D:\a\_work\1\s\src\coreclr\jit\fgdiagnostic.cpp Line: 4392
+// 
+public class Runtime_85226
+{
+    [Fact]
+    public static int Test()
+    {
+        M1();
+        return 100;
+    }
+
+    private static void M1()
+    {
+        for (int var0 = 0; var0 < -1; var0++)
+        {
+            short var1 = 2;
+            if (((ushort)((var0 % (var1 | 1)) % 0) < 0UL))
+            {
+                return;
+            }
+        }
+    }
+}
diff --git a/src/tests/JIT/Regression/JitBlue/Runtime_85226/Runtime_85226.csproj b/src/tests/JIT/Regression/JitBlue/Runtime_85226/Runtime_85226.csproj
new file mode 100644
index 00000000000..de6d5e08882
--- /dev/null
+++ b/src/tests/JIT/Regression/JitBlue/Runtime_85226/Runtime_85226.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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