inline float XMConvertHalfToFloat()

in Inc/DirectXPackedVector.inl [20:67]

• 42 lines of code
• 13 McCabe index (conditional complexity)

inline float XMConvertHalfToFloat(HALF Value) noexcept
{
#if defined(_XM_F16C_INTRINSICS_) && !defined(_XM_NO_INTRINSICS_)
    __m128i V1 = _mm_cvtsi32_si128(static_cast<int>(Value));
    __m128 V2 = _mm_cvtph_ps(V1);
    return _mm_cvtss_f32(V2);
#elif defined(_XM_ARM_NEON_INTRINSICS_) && (defined(_M_ARM64) || defined(_M_HYBRID_X86_ARM64) || defined(_M_ARM64EC) || __aarch64__) && !defined(_XM_NO_INTRINSICS_) && (!defined(__GNUC__) || (__ARM_FP & 2))
    uint16x4_t vHalf = vdup_n_u16(Value);
    float32x4_t vFloat = vcvt_f32_f16(vreinterpret_f16_u16(vHalf));
    return vgetq_lane_f32(vFloat, 0);
#else
    auto Mantissa = static_cast<uint32_t>(Value & 0x03FF);

    uint32_t Exponent = (Value & 0x7C00);
    if (Exponent == 0x7C00) // INF/NAN
    {
        Exponent = 0x8f;
    }
    else if (Exponent != 0)  // The value is normalized
    {
        Exponent = static_cast<uint32_t>((static_cast<int>(Value) >> 10) & 0x1F);
    }
    else if (Mantissa != 0)     // The value is denormalized
    {
        // Normalize the value in the resulting float
        Exponent = 1;

        do
        {
            Exponent--;
            Mantissa <<= 1;
        } while ((Mantissa & 0x0400) == 0);

        Mantissa &= 0x03FF;
    }
    else                        // The value is zero
    {
        Exponent = static_cast<uint32_t>(-112);
    }

    uint32_t Result =
        ((static_cast<uint32_t>(Value) & 0x8000) << 16) // Sign
        | ((Exponent + 112) << 23)                      // Exponent
        | (Mantissa << 13);                             // Mantissa

    return reinterpret_cast<float*>(&Result)[0];
#endif // !_XM_F16C_INTRINSICS_
}