From 802cc04458927f35d7cb18697d6f75ef6f1db205 Mon Sep 17 00:00:00 2001
From: Jan Kotas <jkotas@microsoft.com>
Date: Wed, 16 Aug 2023 15:13:09 -0700
Subject: [PATCH] Revert "[JIT] ARM64 - Temporary fix for `ldp`/`stp`
 optimizations (#90534)"

This reverts commit 99a60c6a5c6671f92c18a032c6dff033a3a2adb7.
---
 src/coreclr/jit/emitarm64.cpp                 |  9 ---
 .../JitBlue/Runtime_85765/Runtime_85765.cs    | 63 -------------------
 .../Runtime_85765/Runtime_85765.csproj        |  8 ---
 3 files changed, 80 deletions(-)
 delete mode 100644 src/tests/JIT/Regression/JitBlue/Runtime_85765/Runtime_85765.cs
 delete mode 100644 src/tests/JIT/Regression/JitBlue/Runtime_85765/Runtime_85765.csproj

diff --git a/src/coreclr/jit/emitarm64.cpp b/src/coreclr/jit/emitarm64.cpp
index f01ad548d2ee04..b4e81322e2a696 100644
--- a/src/coreclr/jit/emitarm64.cpp
+++ b/src/coreclr/jit/emitarm64.cpp
@@ -16615,15 +16615,6 @@ emitter::RegisterOrder emitter::IsOptimizableLdrStrWithPair(
     emitAttr  prevSize   = emitLastIns->idOpSize();
     ssize_t   prevImm    = emitGetInsSC(emitLastIns);
 
-    // If we have this format, the 'imm' and/or 'prevImm' are not scaled(encoded),
-    // therefore we cannot proceed.
-    // TODO: In this context, 'imm' and 'prevImm' are assumed to be scaled(encoded).
-    //       They should never be scaled(encoded) until its about to be written to the buffer.
-    if (fmt == IF_LS_2C || lastInsFmt == IF_LS_2C)
-    {
-        return eRO_none;
-    }
-
     // Signed, *raw* immediate value fits in 7 bits, so for LDP/ STP the raw value is from -64 to +63.
     // For LDR/ STR, there are 9 bits, so we need to limit the range explicitly in software.
     if ((imm < -64) || (imm > 63) || (prevImm < -64) || (prevImm > 63))
diff --git a/src/tests/JIT/Regression/JitBlue/Runtime_85765/Runtime_85765.cs b/src/tests/JIT/Regression/JitBlue/Runtime_85765/Runtime_85765.cs
deleted file mode 100644
index f04eed1b7981c8..00000000000000
--- a/src/tests/JIT/Regression/JitBlue/Runtime_85765/Runtime_85765.cs
+++ /dev/null
@@ -1,63 +0,0 @@
-// 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 Xunit;
-
-public class Runtime_85765
-{
-    public struct S0
-    {
-        public S0(bool f1): this()
-        {
-        }
-    }
-
-    public struct S1
-    {
-        public byte F0;
-        public bool F1;
-        public bool F2;
-    }
-
-    [Fact]
-    public static void Test()
-    {
-        S1 vr2 = M4();
-        vr2.F2 |= vr2.F1;
-        Assert.False(Consume(vr2.F2));
-    }
-
-    [MethodImpl(MethodImplOptions.NoInlining)]
-    public static S1 M4()
-    {
-        S1 var1 = default(S1);
-        var vr0 = new S0(false);
-        return var1;
-    }
-
-    [MethodImpl(MethodImplOptions.NoInlining)]
-    private static bool Consume(bool value)
-    {
-        return value;
-    }
-
-    // ------
-
-    [Fact]
-    public static void Test2()
-    {
-        byte* bytes = stackalloc byte[1024];
-        bytes[0x1A] = 1;
-        bytes[0x1B] = 2;
-        int sum = Foo(bytes);
-        Assert.True(sum == 515);
-    }
-
-    [MethodImpl(MethodImplOptions.NoInlining)]
-    public static int Foo(byte* b)
-    {
-        return Unsafe.ReadUnaligned<int>(ref b[0x1A]) + Unsafe.ReadUnaligned<int>(ref b[0x1B]);
-    }
-}
diff --git a/src/tests/JIT/Regression/JitBlue/Runtime_85765/Runtime_85765.csproj b/src/tests/JIT/Regression/JitBlue/Runtime_85765/Runtime_85765.csproj
deleted file mode 100644
index de6d5e08882e86..00000000000000
--- a/src/tests/JIT/Regression/JitBlue/Runtime_85765/Runtime_85765.csproj
+++ /dev/null
@@ -1,8 +0,0 @@
-<Project Sdk="Microsoft.NET.Sdk">
-  <PropertyGroup>
-    <Optimize>True</Optimize>
-  </PropertyGroup>
-  <ItemGroup>
-    <Compile Include="$(MSBuildProjectName).cs" />
-  </ItemGroup>
-</Project>