JUCE/modules/juce_dsp/containers/juce_SIMDRegister_Impl.h

/*
  ==============================================================================

   This file is part of the JUCE 6 technical preview.
   Copyright (c) 2020 - Raw Material Software Limited

   You may use this code under the terms of the GPL v3
   (see www.gnu.org/licenses).

   For this technical preview, this file is not subject to commercial licensing.

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

namespace juce
{
namespace dsp
{


//==============================================================================
template <typename Type>
struct SIMDRegister<Type>::ElementAccess
{
    operator Type() const                                { return simd.get (idx); }
    ElementAccess& operator= (Type scalar) noexcept      { simd.set (idx, scalar); return *this; }
    ElementAccess& operator= (ElementAccess& o) noexcept { return operator= ((Type) o); }

private:
    friend struct SIMDRegister;
    ElementAccess (SIMDRegister& owner, size_t index) noexcept : simd (owner), idx (index) {}
    SIMDRegister& simd;
    size_t idx;
};

#ifndef DOXYGEN
//==============================================================================
/* This class is used internally by SIMDRegister to abstract away differences
   in operations which are different for complex and pure floating point types. */

// the pure floating-point version
template <typename Scalar>
struct CmplxSIMDOps
{
    using vSIMDType = typename SIMDNativeOps<Scalar>::vSIMDType;

    static vSIMDType JUCE_VECTOR_CALLTYPE load (const Scalar* a) noexcept
    {
        return SIMDNativeOps<Scalar>::load (a);
    }

    static void JUCE_VECTOR_CALLTYPE store (vSIMDType value, Scalar* dest) noexcept
    {
        SIMDNativeOps<Scalar>::store (value, dest);
    }

    static vSIMDType JUCE_VECTOR_CALLTYPE expand (Scalar s) noexcept
    {
        return SIMDNativeOps<Scalar>::expand (s);
    }

    static Scalar JUCE_VECTOR_CALLTYPE get (vSIMDType v, std::size_t i) noexcept
    {
        return SIMDNativeOps<Scalar>::get (v, i);
    }

    static vSIMDType JUCE_VECTOR_CALLTYPE set (vSIMDType v, std::size_t i, Scalar s) noexcept
    {
        return SIMDNativeOps<Scalar>::set (v, i, s);
    }

    static Scalar JUCE_VECTOR_CALLTYPE sum (vSIMDType a)  noexcept
    {
        return SIMDNativeOps<Scalar>::sum (a);
    }

    static vSIMDType JUCE_VECTOR_CALLTYPE mul (vSIMDType a, vSIMDType b) noexcept
    {
        return SIMDNativeOps<Scalar>::mul (a, b);
    }

    static vSIMDType JUCE_VECTOR_CALLTYPE muladd (vSIMDType a, vSIMDType b, vSIMDType c) noexcept
    {
        return SIMDNativeOps<Scalar>::multiplyAdd (a, b, c);
    }
};

// The pure complex version
template <typename Scalar>
struct CmplxSIMDOps<std::complex<Scalar>>
{
    using vSIMDType = typename SIMDNativeOps<Scalar>::vSIMDType;

    static vSIMDType JUCE_VECTOR_CALLTYPE load (const std::complex<Scalar>* a) noexcept
    {
        return SIMDNativeOps<Scalar>::load (reinterpret_cast<const Scalar*> (a));
    }

    static void JUCE_VECTOR_CALLTYPE store (vSIMDType value, std::complex<Scalar>* dest) noexcept
    {
        SIMDNativeOps<Scalar>::store (value, reinterpret_cast<Scalar*> (dest));
    }

    static vSIMDType JUCE_VECTOR_CALLTYPE expand (std::complex<Scalar> s) noexcept
    {
        const int n = sizeof (vSIMDType) / sizeof (Scalar);

        union
        {
            vSIMDType v;
            Scalar floats[(size_t) n];
        } u;

        for (int i = 0; i < n; ++i)
            u.floats[i] = (i & 1) == 0 ? s.real() : s.imag();

        return u.v;
    }

    static std::complex<Scalar> JUCE_VECTOR_CALLTYPE get (vSIMDType v, std::size_t i) noexcept
    {
        auto j = i << 1;
        return std::complex<Scalar> (SIMDNativeOps<Scalar>::get (v, j), SIMDNativeOps<Scalar>::get (v, j + 1));
    }

    static vSIMDType JUCE_VECTOR_CALLTYPE set (vSIMDType v, std::size_t i, std::complex<Scalar> s) noexcept
    {
        auto j = i << 1;
        return SIMDNativeOps<Scalar>::set (SIMDNativeOps<Scalar>::set (v, j, s.real()), j + 1, s.imag());
    }

    static std::complex<Scalar> JUCE_VECTOR_CALLTYPE sum (vSIMDType a)  noexcept
    {
        vSIMDType result = SIMDNativeOps<Scalar>::oddevensum (a);
        auto* ptr = reinterpret_cast<const Scalar*> (&result);
        return std::complex<Scalar> (ptr[0], ptr[1]);
    }

    static vSIMDType JUCE_VECTOR_CALLTYPE mul (vSIMDType a, vSIMDType b)  noexcept
    {
        return SIMDNativeOps<Scalar>::cmplxmul (a, b);
    }

    static vSIMDType JUCE_VECTOR_CALLTYPE muladd (vSIMDType a, vSIMDType b, vSIMDType c) noexcept
    {
        return SIMDNativeOps<Scalar>::add (a, SIMDNativeOps<Scalar>::cmplxmul (b, c));
    }
};
#endif

//==============================================================================
 namespace util
 {
     template <typename Type>
     inline void snapToZero (SIMDRegister<Type>&) noexcept      {}
 }

} // namespace dsp

// Extend some common used global functions to SIMDRegister types
template <typename Type>
inline dsp::SIMDRegister<Type> JUCE_VECTOR_CALLTYPE jmin (dsp::SIMDRegister<Type> a, dsp::SIMDRegister<Type> b) { return dsp::SIMDRegister<Type>::min (a, b); }
template <typename Type>
inline dsp::SIMDRegister<Type> JUCE_VECTOR_CALLTYPE jmax (dsp::SIMDRegister<Type> a, dsp::SIMDRegister<Type> b) { return dsp::SIMDRegister<Type>::max (a, b); }

} // namespace juce