JIT: Wrong result with `ConditionalExtractAfterLastActiveElement`

[jakobbotsch]

// Generated by Fuzzlyn v2.5 on 2025-03-26 17:41:37
// Run on Arm64 Windows
// Seed: 14066702134085227730-vectort,vector64,vector128,armadvsimd,armadvsimdarm64,armaes,armarmbase,armarmbasearm64,armcrc32,armcrc32arm64,armdp,armrdm,armrdmarm64,armsha1,armsha256,armsve
// Reduced from 44.1 KiB to 0.7 KiB in 00:00:48
// Debug: Outputs <0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0>
// Release: Outputs <144, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0>
using System;
using System.Numerics;
using System.Runtime.Intrinsics;
using System.Runtime.Intrinsics.Arm;

public class C4
{
    public Vector<byte> F1;
}

public class Program
{
    public static IRuntime s_rt;
    public static void Main()
    {
        s_rt = new Runtime();
        C4 vr3 = new C4();
        var vr4 = vr3.F1;
        var vr5 = vr3.F1;
        var vr6 = vr3.F1;
        Vector<byte> vr7 = Sve.ConditionalExtractAfterLastActiveElement(vr4, vr5, vr6);
        s_rt.WriteLine(vr7);
    }
}

public interface IRuntime
{
    void WriteLine<T>(T value);
}

public class Runtime : IRuntime
{
    public void WriteLine<T>(T value) => System.Console.WriteLine(value);
}

cc @dotnet/jit-contrib @dotnet/arm64-contrib

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[kunalspathak]

This could be from #113860

[kunalspathak]

This seems to be an encoding issue. We are generating something like this, but if we refer Mov documentation, it was getting decoded as orr z0, z16, z0 instead.

04603200          mov     z0.b, z16.b