[release/8.0-staging] JIT: fix issue with out of order importer spilling around some calls

src/coreclr/jit/importer.cpp

@@ -453,6 +453,11 @@ void Compiler::impAppendStmt(Statement* stmt, unsigned chkLevel, bool checkConsu
             }
         }
 
+        // In the case of GT_RET_EXPR any subsequent spills will appear in the wrong place -- after
+        // the call. We need to move them to before the call
+        //
+        Statement* lastStmt = impLastStmt;
+
         if ((dstVarDsc != nullptr) && !dstVarDsc->IsAddressExposed() && !dstVarDsc->lvHasLdAddrOp)
         {
             impSpillLclRefs(lvaGetLclNum(dstVarDsc), chkLevel);
@@ -480,6 +485,40 @@ void Compiler::impAppendStmt(Statement* stmt, unsigned chkLevel, bool checkConsu
         {
             impSpillSpecialSideEff();
         }
+
+        if ((lastStmt != impLastStmt) && expr->OperIs(GT_RET_EXPR))
+        {
+            GenTree* const call = expr->AsRetExpr()->gtInlineCandidate;
+            JITDUMP("\nimpAppendStmt: after sinking a local struct store into inline candidate [%06u], we need to "
+                    "reorder subsequent spills.\n",
+                    dspTreeID(call));
+
+            // Move all newly appended statements to just before the call's statement.
+            // First, find the statement containing the call.
+            //
+            Statement* insertBeforeStmt = lastStmt;
+
+            while (insertBeforeStmt->GetRootNode() != call)
+            {
+                assert(insertBeforeStmt != impStmtList);
+                insertBeforeStmt = insertBeforeStmt->GetPrevStmt();
+            }
+
+            Statement* movingStmt = lastStmt->GetNextStmt();
+
+            JITDUMP("Moving " FMT_STMT " through " FMT_STMT " before " FMT_STMT "\n", movingStmt->GetID(),
+                    impLastStmt->GetID(), insertBeforeStmt->GetID());
+
+            // We move these backwards, so must keep moving the insert
+            // point to keep them in order.
+            //
+            while (impLastStmt != lastStmt)
+            {
+                Statement* movingStmt = impExtractLastStmt();
+                impInsertStmtBefore(movingStmt, insertBeforeStmt);
+                insertBeforeStmt = movingStmt;
+            }
+        }
     }
 
     impAppendStmtCheck(stmt, chkLevel);

src/tests/JIT/Regression/JitBlue/Runtime_95349/Runtime_95349.cs

@@ -0,0 +1,61 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+// Issues with stack spill ordering around some GDVs
+// Compile with <DebugType>None</DebugType>
+
+using System;
+using System.Runtime.CompilerServices;
+using System.Threading;
+using Xunit;
+
+class P
+{
+  virtual public (double x, double y) XY() => (0, 0);
+}
+
+class P1 : P
+{
+  override public (double x, double y) XY() => (1, 2);
+}
+
+public class Runtime_95349
+{
+    [MethodImpl(MethodImplOptions.NoInlining)]
+    static int Problem(P p, int n, (double x, double y) tuple)
+    {
+        int wn = 0;
+        for (int i = 0; i < n; i++)
+        {
+            (double x, double y) tupleTmp = tuple;
+            tuple = p.XY();
+            (_, double f) = tupleTmp;
+            wn = Wn(wn, f, tuple.y);
+        }
+
+        return wn;
+    }
+
+    [MethodImpl(MethodImplOptions.NoInlining)]
+    static int Wn(int wn, double f, double y)
+    {
+        wn += (f == -1) ? 1 : 0;
+        return wn;
+    }
+
+    [Fact]
+    public static void Test()
+    {
+        P p = new P1();
+        int n = 100_000;
+        for (int i = 0; i < 100; i++)
+        {
+            _ = Problem(p, n, (-1, -1));
+            Thread.Sleep(30);
+        }
+
+        int r = Problem(p, n, (-1, -1));
+        Console.WriteLine($"r = {r} (expected 1)");
+        Assert.Equal(1, r);
+    }
+}

src/tests/JIT/Regression/JitBlue/Runtime_95349/Runtime_95349.csproj

@@ -0,0 +1,9 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <Optimize>True</Optimize>
+    <DebugType>None</DebugType>
+  </PropertyGroup>
+  <ItemGroup>
+    <Compile Include="$(MSBuildProjectName).cs" />
+  </ItemGroup>
+</Project>