public static bool Equal(Vector128 <float> vector1, Vector128 <float> vector2)
{
// This implementation is based on the DirectX Math Library XMVector4Equal method
// https://github.com/microsoft/DirectXMath/blob/master/Inc/DirectXMathVector.inl
if (AdvSimd.Arm64.IsSupported)
{
Vector128 <uint> vResult = AdvSimd.CompareEqual(vector1, vector2).AsUInt32();
Vector64 <byte> vResult0 = vResult.GetLower().AsByte();
Vector64 <byte> vResult1 = vResult.GetUpper().AsByte();
Vector64 <byte> vTemp10 = AdvSimd.Arm64.ZipLow(vResult0, vResult1);
Vector64 <byte> vTemp11 = AdvSimd.Arm64.ZipHigh(vResult0, vResult1);
Vector64 <ushort> vTemp21 = AdvSimd.Arm64.ZipHigh(vTemp10.AsUInt16(), vTemp11.AsUInt16());
return(vTemp21.AsUInt32().GetElement(1) == 0xFFFFFFFF);
}
else if (Sse.IsSupported)
{
return(Sse.MoveMask(Sse.CompareNotEqual(vector1, vector2)) == 0);
}
else
{
// Redundant test so we won't prejit remainder of this method on platforms without AdvSimd.
throw new PlatformNotSupportedException();
}
}
private static void NarrowFourUtf16CharsToAsciiAndWriteToBuffer(ref byte outputBuffer, ulong value)
{
Debug.Assert(AllCharsInUInt64AreAscii(value));
#if NETCOREAPP3_1
if (Bmi2.X64.IsSupported)
{
// BMI2 will work regardless of the processor's endianness.
Unsafe.WriteUnaligned(ref outputBuffer, (uint)Bmi2.X64.ParallelBitExtract(value, 0x00FF00FF_00FF00FFul));
}
#else
if (Sse2.X64.IsSupported)
{
// Narrows a vector of words [ w0 w1 w2 w3 ] to a vector of bytes
// [ b0 b1 b2 b3 b0 b1 b2 b3 ], then writes 4 bytes (32 bits) to the destination.
Vector128 <short> vecWide = Sse2.X64.ConvertScalarToVector128UInt64(value).AsInt16();
Vector128 <uint> vecNarrow = Sse2.PackUnsignedSaturate(vecWide, vecWide).AsUInt32();
Unsafe.WriteUnaligned <uint>(ref outputBuffer, Sse2.ConvertToUInt32(vecNarrow));
}
else if (AdvSimd.IsSupported)
{
// Narrows a vector of words [ w0 w1 w2 w3 ] to a vector of bytes
// [ b0 b1 b2 b3 * * * * ], then writes 4 bytes (32 bits) to the destination.
Vector128 <short> vecWide = Vector128.CreateScalarUnsafe(value).AsInt16();
Vector64 <byte> lower = AdvSimd.ExtractNarrowingSaturateUnsignedLower(vecWide);
Unsafe.WriteUnaligned <uint>(ref outputBuffer, lower.AsUInt32().ToScalar());
}
#endif
else
{
if (BitConverter.IsLittleEndian)
{
outputBuffer = (byte)value;
value >>= 16;
Unsafe.Add(ref outputBuffer, 1) = (byte)value;
value >>= 16;
Unsafe.Add(ref outputBuffer, 2) = (byte)value;
value >>= 16;
Unsafe.Add(ref outputBuffer, 3) = (byte)value;
}
else
{
Unsafe.Add(ref outputBuffer, 3) = (byte)value;
value >>= 16;
Unsafe.Add(ref outputBuffer, 2) = (byte)value;
value >>= 16;
Unsafe.Add(ref outputBuffer, 1) = (byte)value;
value >>= 16;
outputBuffer = (byte)value;
}
}
}
