극저온 방사광 X-선 나노회절 기반 자기 스커미온(Magnetic Skyrmion) 레이스트랙 메모리 전류 유도 횡변위 홀 효과 억제 서보 아키텍처 (.NET 9 C# SIMD)

using System;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Runtime.Intrinsics;
using System.Runtime.Intrinsics.X86;

namespace ZeliDesk.Quantum.Spintronics
{
    /// <summary>
    /// 자기 스커미온(Magnetic Skyrmion) 레이스트랙 홀 효과(SkHE) 억제 서보
    /// GC 제로 할당 ref struct 및 AVX-256 SIMD 가속화
    /// </summary>
    public ref struct SkyrmionRacetrackServo
    {
        private readonly ReadOnlySpan<float> _transversePositions; // 횡방향 변위 y (nm)
        private readonly ReadOnlySpan<float> _driveCurrents;       // 구동 전류 밀도 j_e (MA/cm^2)
        private readonly Span<float> _deflectionErrors;           // 산출된 에지 이탈 오차 (nm)
        private readonly Span<float> _restoringVoltages;          // 피에조 복원 전압 지령 (V)

        private readonly float _hallCoeff;      // 스커미온 홀 편향 계수 (nm / (MA/cm^2))
        private readonly float _restoringGain;  // 복원 전압 게인 (V/nm)
        private readonly float _trackCenterY;   // 트랙 중심선 좌표 (nm)

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public SkyrmionRacetrackServo(
            ReadOnlySpan<float> transversePositions,
            ReadOnlySpan<float> driveCurrents,
            Span<float> deflectionErrors,
            Span<float> restoringVoltages,
            float hallCoeff = 0.18f,
            float restoringGain = 0.45f,
            float trackCenterY = 0.0f)
        {
            _transversePositions = transversePositions;
            _driveCurrents = driveCurrents;
            _deflectionErrors = deflectionErrors;
            _restoringVoltages = restoringVoltages;
            _hallCoeff = hallCoeff;
            _restoringGain = restoringGain;
            _trackCenterY = trackCenterY;
        }

        /// <summary>
        /// 8채널 나노트랙의 스커미온 횡변위를 SIMD 병렬 연산하여 에지 충돌 방지 전압 도출
        /// </summary>
        [MethodImpl(MethodImplOptions.AggressiveOptimization)]
        public void ExecuteSkyrmionLockLoop()
        {
            int length = _transversePositions.Length;
            int simdLength = length - (length % 8);

            Vector256<float> vCenter = Vector256.Create(_trackCenterY);
            Vector256<float> vHall = Vector256.Create(_hallCoeff);
            Vector256<float> vGain = Vector256.Create(_restoringGain);

            int i = 0;
            if (Avx2.IsSupported)
            {
                for (; i < simdLength; i += 8)
                {
                    Vector256<float> vY = Vector256.Create(MemoryMarshal.Cast<float, Vector256<float>>(_transversePositions.Slice(i, 8))[0]);
                    Vector256<float> vJ = Vector256.Create(MemoryMarshal.Cast<float, Vector256<float>>(_driveCurrents.Slice(i, 8))[0]);

                    // 중심 오차: ErrorY = y - Center
                    Vector256<float> vErrY = Avx.Subtract(vY, vCenter);

                    // 스커미온 홀 예상 편향: HallDrift = HallCoeff * J
                    Vector256<float> vHallDrift = Avx.Multiply(vHall, vJ);

                    // 총 능동 복원 전압 = -Gain * (ErrorY + HallDrift)
                    Vector256<float> vTotalOffset = Avx.Add(vErrY, vHallDrift);
                    Vector256<float> vVrest = Avx.Multiply(Avx.Subtract(Vector256<float>.Zero, vTotalOffset), vGain);

                    vErrY.CopyTo(_deflectionErrors.Slice(i, 8));
                    vVrest.CopyTo(_restoringVoltages.Slice(i, 8));
                }
            }

            for (; i < length; i++)
            {
                float errY = _transversePositions[i] - _trackCenterY;
                float hallDrift = _hallCoeff * _driveCurrents[i];
                _deflectionErrors[i] = errY;
                _restoringVoltages[i] = -_restoringGain * (errY + hallDrift);
            }
        }
    }
}