Eigen/src/Geometry/arch/Geometry_SIMD.h

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2009 Rohit Garg <rpg.314@gmail.com>
// Copyright (C) 2009-2010 Gael Guennebaud <gael.guennebaud@inria.fr>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

#ifndef EIGEN_GEOMETRY_SIMD_H
#define EIGEN_GEOMETRY_SIMD_H

// IWYU pragma: private
#include "../InternalHeaderCheck.h"

namespace Eigen {

namespace internal {

template <class Derived, class OtherDerived>
struct quat_product<Architecture::Target, Derived, OtherDerived, float> {
  enum {
    AAlignment = traits<Derived>::Alignment,
    BAlignment = traits<OtherDerived>::Alignment,
    ResAlignment = traits<Quaternion<float> >::Alignment
  };
  static inline Quaternion<float> run(const QuaternionBase<Derived>& _a, const QuaternionBase<OtherDerived>& _b) {
    evaluator<typename Derived::Coefficients> ae(_a.coeffs());
    evaluator<typename OtherDerived::Coefficients> be(_b.coeffs());
    Quaternion<float> res;
    const float neg_zero = numext::bit_cast<float>(0x80000000u);
    const float arr[4] = {0.f, 0.f, 0.f, neg_zero};
    const Packet4f mask = ploadu<Packet4f>(arr);
    Packet4f a = ae.template packet<AAlignment, Packet4f>(0);
    Packet4f b = be.template packet<BAlignment, Packet4f>(0);
    Packet4f s1 = pmul(vec4f_swizzle1(a, 1, 2, 0, 2), vec4f_swizzle1(b, 2, 0, 1, 2));
    Packet4f s2 = pmul(vec4f_swizzle1(a, 3, 3, 3, 1), vec4f_swizzle1(b, 0, 1, 2, 1));
    pstoret<float, Packet4f, ResAlignment>(
        &res.x(), padd(psub(pmul(a, vec4f_swizzle1(b, 3, 3, 3, 3)),
                            pmul(vec4f_swizzle1(a, 2, 0, 1, 0), vec4f_swizzle1(b, 1, 2, 0, 0))),
                       pxor(mask, padd(s1, s2))));

    return res;
  }
};

template <class Derived>
struct quat_conj<Architecture::Target, Derived, float> {
  enum { ResAlignment = traits<Quaternion<float> >::Alignment };
  static inline Quaternion<float> run(const QuaternionBase<Derived>& q) {
    evaluator<typename Derived::Coefficients> qe(q.coeffs());
    Quaternion<float> res;
    const float neg_zero = numext::bit_cast<float>(0x80000000u);
    const float arr[4] = {neg_zero, neg_zero, neg_zero, 0.f};
    const Packet4f mask = ploadu<Packet4f>(arr);
    pstoret<float, Packet4f, ResAlignment>(&res.x(),
                                           pxor(mask, qe.template packet<traits<Derived>::Alignment, Packet4f>(0)));
    return res;
  }
};

template <typename VectorLhs, typename VectorRhs>
struct cross3_impl<Architecture::Target, VectorLhs, VectorRhs, float, true> {
  using DstPlainType = typename plain_matrix_type<VectorLhs>::type;
  static constexpr int DstAlignment = evaluator<DstPlainType>::Alignment;
  static constexpr int LhsAlignment = evaluator<VectorLhs>::Alignment;
  static constexpr int RhsAlignment = evaluator<VectorRhs>::Alignment;
  static inline DstPlainType run(const VectorLhs& lhs, const VectorRhs& rhs) {
    evaluator<VectorLhs> lhs_eval(lhs);
    evaluator<VectorRhs> rhs_eval(rhs);
    Packet4f a = lhs_eval.template packet<LhsAlignment, Packet4f>(0);
    Packet4f b = rhs_eval.template packet<RhsAlignment, Packet4f>(0);
    Packet4f mul1 = pmul(vec4f_swizzle1(a, 1, 2, 0, 3), vec4f_swizzle1(b, 2, 0, 1, 3));
    Packet4f mul2 = pmul(vec4f_swizzle1(a, 2, 0, 1, 3), vec4f_swizzle1(b, 1, 2, 0, 3));
    DstPlainType res;
    pstoret<float, Packet4f, DstAlignment>(&res.x(), psub(mul1, mul2));
    return res;
  }
};

#if (defined EIGEN_VECTORIZE_SSE) || (EIGEN_ARCH_ARM64)

template <class Derived, class OtherDerived>
struct quat_product<Architecture::Target, Derived, OtherDerived, double> {
  enum { BAlignment = traits<OtherDerived>::Alignment, ResAlignment = traits<Quaternion<double> >::Alignment };

  static inline Quaternion<double> run(const QuaternionBase<Derived>& _a, const QuaternionBase<OtherDerived>& _b) {
    Quaternion<double> res;

    evaluator<typename Derived::Coefficients> ae(_a.coeffs());
    evaluator<typename OtherDerived::Coefficients> be(_b.coeffs());

    const double* a = _a.coeffs().data();
    Packet2d b_xy = be.template packet<BAlignment, Packet2d>(0);
    Packet2d b_zw = be.template packet<BAlignment, Packet2d>(2);
    Packet2d a_xx = pset1<Packet2d>(a[0]);
    Packet2d a_yy = pset1<Packet2d>(a[1]);
    Packet2d a_zz = pset1<Packet2d>(a[2]);
    Packet2d a_ww = pset1<Packet2d>(a[3]);

    // two temporaries:
    Packet2d t1, t2;

    /*
     * t1 = ww*xy + yy*zw
     * t2 = zz*xy - xx*zw
     * res.xy = t1 +/- swap(t2)
     */
    t1 = padd(pmul(a_ww, b_xy), pmul(a_yy, b_zw));
    t2 = psub(pmul(a_zz, b_xy), pmul(a_xx, b_zw));
    pstoret<double, Packet2d, ResAlignment>(&res.x(), paddsub(t1, preverse(t2)));

    /*
     * t1 = ww*zw - yy*xy
     * t2 = zz*zw + xx*xy
     * res.zw = t1 -/+ swap(t2) = swap( swap(t1) +/- t2)
     */
    t1 = psub(pmul(a_ww, b_zw), pmul(a_yy, b_xy));
    t2 = padd(pmul(a_zz, b_zw), pmul(a_xx, b_xy));
    pstoret<double, Packet2d, ResAlignment>(&res.z(), preverse(paddsub(preverse(t1), t2)));

    return res;
  }
};

template <class Derived>
struct quat_conj<Architecture::Target, Derived, double> {
  enum { ResAlignment = traits<Quaternion<double> >::Alignment };
  static inline Quaternion<double> run(const QuaternionBase<Derived>& q) {
    evaluator<typename Derived::Coefficients> qe(q.coeffs());
    Quaternion<double> res;
    const double neg_zero = numext::bit_cast<double>(0x8000000000000000ull);
    const double arr1[2] = {neg_zero, neg_zero};
    const double arr2[2] = {neg_zero, 0.0};
    const Packet2d mask0 = ploadu<Packet2d>(arr1);
    const Packet2d mask2 = ploadu<Packet2d>(arr2);
    pstoret<double, Packet2d, ResAlignment>(&res.x(),
                                            pxor(mask0, qe.template packet<traits<Derived>::Alignment, Packet2d>(0)));
    pstoret<double, Packet2d, ResAlignment>(&res.z(),
                                            pxor(mask2, qe.template packet<traits<Derived>::Alignment, Packet2d>(2)));
    return res;
  }
};

#endif  // end EIGEN_VECTORIZE_SSE_OR_EIGEN_ARCH_ARM64

}  // end namespace internal

}  // end namespace Eigen

#endif  // EIGEN_GEOMETRY_SIMD_H