From 2b863217d84e6e0b02d60bc50e6624fd1d0f25ae Mon Sep 17 00:00:00 2001
From: Andy Ayers <andya@microsoft.com>
Date: Fri, 27 May 2022 14:55:50 -0700
Subject: [PATCH] JIT: allow pinvoke calli helper in TreatAsShouldHaveRetBufArg

If we have multiple cold pinvokes in return positions that return
structs by value and we are merging returns, we will end up querying
these calls post-morph, and may see them using CORINFO_HELP_PINVOKE_CALLI.

Fixes #69612.
---
 src/coreclr/jit/gentree.cpp                   | 12 ++--
 .../JitBlue/Runtime_69612/Runtime_69612.cs    | 64 +++++++++++++++++++
 .../Runtime_69612/Runtime_69612.csproj        | 26 ++++++++
 3 files changed, 98 insertions(+), 4 deletions(-)
 create mode 100644 src/tests/JIT/Regression/JitBlue/Runtime_69612/Runtime_69612.cs
 create mode 100644 src/tests/JIT/Regression/JitBlue/Runtime_69612/Runtime_69612.csproj

diff --git a/src/coreclr/jit/gentree.cpp b/src/coreclr/jit/gentree.cpp
index 526e1da038475a..ea690b31eef2ce 100644
--- a/src/coreclr/jit/gentree.cpp
+++ b/src/coreclr/jit/gentree.cpp
@@ -2097,14 +2097,14 @@ bool GenTreeCall::TreatAsShouldHaveRetBufArg(Compiler* compiler) const
         return true;
     }
 
-    // If we see a Jit helper call that returns a TYP_STRUCT we will
+    // If we see a Jit helper call that returns a TYP_STRUCT we may
     // transform it as if it has a Return Buffer Argument
     //
     if (IsHelperCall() && (gtReturnType == TYP_STRUCT))
     {
-        // There are two possible helper calls that use this path:
-        //  CORINFO_HELP_GETFIELDSTRUCT and CORINFO_HELP_UNBOX_NULLABLE
-        //
+        // There are three possible helper calls that use this path:
+        //  CORINFO_HELP_GETFIELDSTRUCT,  CORINFO_HELP_UNBOX_NULLABLE
+        //  CORINFO_HELP_PINVOKE_CALLI
         CorInfoHelpFunc helpFunc = compiler->eeGetHelperNum(gtCallMethHnd);
 
         if (helpFunc == CORINFO_HELP_GETFIELDSTRUCT)
@@ -2115,6 +2115,10 @@ bool GenTreeCall::TreatAsShouldHaveRetBufArg(Compiler* compiler) const
         {
             return true;
         }
+        else if (helpFunc == CORINFO_HELP_PINVOKE_CALLI)
+        {
+            return false;
+        }
         else
         {
             assert(!"Unexpected JIT helper in TreatAsShouldHaveRetBufArg");
diff --git a/src/tests/JIT/Regression/JitBlue/Runtime_69612/Runtime_69612.cs b/src/tests/JIT/Regression/JitBlue/Runtime_69612/Runtime_69612.cs
new file mode 100644
index 00000000000000..a8859d53963e1b
--- /dev/null
+++ b/src/tests/JIT/Regression/JitBlue/Runtime_69612/Runtime_69612.cs
@@ -0,0 +1,64 @@
+// 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 System.Runtime.CompilerServices;
+using System.Threading;
+
+ref struct NewReference
+{
+    public IntPtr pointer;
+}
+
+static unsafe class Delegates
+{
+    static Delegates()
+    {
+        PyLong_FromLongLong = (delegate* unmanaged[Cdecl]<long, NewReference>)0xbadcab;
+        z = 100;
+    }
+
+    public static delegate* unmanaged[Cdecl]<long, NewReference> PyLong_FromLongLong { get; }
+    public static long z;
+}
+
+class Runtime_69612
+{
+    static NewReference ToPython(object value, Type type)
+    {
+        TypeCode tc = Type.GetTypeCode(type);
+        
+        switch (tc)
+        {
+            case TypeCode.Byte:
+                return PyInt_FromInt32((byte)value);
+            case TypeCode.Int16:
+                return PyInt_FromInt32((short)value);
+            case TypeCode.UInt16:
+                return PyInt_FromInt32((ushort)value);
+            case TypeCode.Int32:
+                return PyInt_FromInt32((int)value);
+            default:
+                return new NewReference();
+        }
+    }
+
+    static NewReference PyInt_FromInt32(int value) => PyLong_FromLongLong(value);
+
+    unsafe static NewReference PyLong_FromLongLong(long value) => Delegates.PyLong_FromLongLong(value);
+
+    [MethodImpl(MethodImplOptions.NoOptimization)]
+    static int Main()
+    {
+        for (int i = 0; i < 100; i++)
+        {
+            _ =  ToPython(Delegates.z, typeof(long));
+            Thread.Sleep(15);
+        }
+
+        Thread.Sleep(50);
+        _ = ToPython(Delegates.z, typeof(long));
+        return 100;
+
+    }
+}
diff --git a/src/tests/JIT/Regression/JitBlue/Runtime_69612/Runtime_69612.csproj b/src/tests/JIT/Regression/JitBlue/Runtime_69612/Runtime_69612.csproj
new file mode 100644
index 00000000000000..8015778d2fc9b3
--- /dev/null
+++ b/src/tests/JIT/Regression/JitBlue/Runtime_69612/Runtime_69612.csproj
@@ -0,0 +1,26 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <Optimize>True</Optimize>
+    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
+  </PropertyGroup>
+  <ItemGroup>
+    <Compile Include="$(MSBuildProjectName).cs" />
+  </ItemGroup>
+  <PropertyGroup>
+    <CLRTestBatchPreCommands><![CDATA[
+$(CLRTestBatchPreCommands)
+set COMPlus_TieredCompilation=1
+set COMPlus_TieredPGO=1
+set COMPlus_TC_QuickJitForLoops=1
+set COMPlus_TC_OnStackReplacement=1
+]]></CLRTestBatchPreCommands>
+    <BashCLRTestPreCommands><![CDATA[
+$(BashCLRTestPreCommands)
+export COMPlus_TieredCompilation=1
+export COMPlus_TieredPGO=1
+export COMPlus_TC_QuickJitForLoops=1
+export COMPlus_TC_OnStackReplacement=1
+]]></BashCLRTestPreCommands>
+  </PropertyGroup>
+</Project>
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