JIT: Bad result with `Sve.ShiftLeftLogical`

[jakobbotsch]

// Generated by Fuzzlyn v3.3 on 2026-01-18 15:19:35
// Run on Arm64 Linux
// Seed: 9708475157171387186-vectort,vector64,vector128,armadvsimd,armadvsimdarm64,armaes,armarmbase,armarmbasearm64,armcrc32,armcrc32arm64,armdp,armrdm,armrdmarm64,armsha1,armsha256,armsve,armsve2
// Reduced from 131.5 KiB to 0.3 KiB in 00:00:46
// Debug: Outputs <2, 2, 2, 2>
// Release: Outputs <2, 2, 1, 1>
using System.Numerics;
using System.Runtime.Intrinsics.Arm;

public class Program
{
    public static void Main()
    {
        var vr5 = Vector.Create<int>(1);
        var vr6 = Vector.Create<ulong>(1);
        var vr7 = Sve.ShiftLeftLogical(vr5, vr6);
        System.Console.WriteLine(vr7);
    }
}

cc @dotnet/arm64-contrib

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[jakobbotsch]

Similar examples for other shifts:

// Generated by Fuzzlyn v3.3 on 2026-01-18 15:17:47
// Run on Arm64 Linux
// Seed: 18332382755258128104-vectort,vector64,vector128,armadvsimd,armadvsimdarm64,armaes,armarmbase,armarmbasearm64,armcrc32,armcrc32arm64,armdp,armrdm,armrdmarm64,armsha1,armsha256,armsve,armsve2
// Reduced from 30.2 KiB to 0.4 KiB in 00:00:21
// Debug: Outputs <0, 0, 0, 0>
// Release: Outputs <0, 0, 1, 1>
using System.Numerics;
using System.Runtime.Intrinsics.Arm;

public class Program
{
    public static Vector<int> s_9;
    public static void Main()
    {
        var vr3 = Vector.Create<int>(1);
        var vr4 = Vector.Create<ulong>(1);
        var vr5 = Sve.ShiftRightArithmetic(vr3, vr4);
        s_9 = Sve.AbsoluteDifference(s_9, vr5);
        System.Console.WriteLine(s_9);
    }
}

// Generated by Fuzzlyn v3.3 on 2026-01-18 15:17:22
// Run on Arm64 Linux
// Seed: 3533807354265102197-vectort,vector64,vector128,armadvsimd,armadvsimdarm64,armaes,armarmbase,armarmbasearm64,armcrc32,armcrc32arm64,armdp,armrdm,armrdmarm64,armsha1,armsha256,armsve,armsve2
// Reduced from 63.7 KiB to 0.4 KiB in 00:00:30
// Debug: Outputs <0, 0, 0, 0, 1, 1, 1, 1>
// Release: Outputs <0, 0, 1, 1, 1, 1, 1, 1>
using System.Numerics;
using System.Runtime.Intrinsics;
using System.Runtime.Intrinsics.Arm;

public class Program
{
    public static void Main()
    {
        var vr3 = Vector.Create<ushort>(1);
        var vr4 = Vector128.CreateScalar(3551845845691399992UL).AsVector();
        var vr5 = Sve.ShiftRightLogical(vr3, vr4);
        System.Console.WriteLine(vr5);
    }
}

[EgorBo]

cc @dotnet/arm64-contrib