Complex.h

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// copyright (c) 2023 zang ruochen <zangruochen@loongson.cn>
// copyright (c) 2024 XiWei Gu <guxiwei-hf@loongson.cn>
//
// 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_COMPLEX_LSX_H
#define EIGEN_COMPLEX_LSX_H

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

namespace Eigen {

namespace internal {

//---------- float ----------
struct Packet2cf {
  EIGEN_STRONG_INLINE Packet2cf() {}
  EIGEN_STRONG_INLINE explicit Packet2cf(const __m128& a) : v(a) {}
  Packet4f v;
};

template <>
struct packet_traits<std::complex<float> > : default_packet_traits {
  typedef Packet2cf type;
  typedef Packet2cf half;
  enum {
    Vectorizable = 1,
    AlignedOnScalar = 1,
    size = 2,

    HasAdd = 1,
    HasSub = 1,
    HasMul = 1,
    HasDiv = 1,
    HasNegate = 1,
    HasSqrt = 1,
    HasExp = 1,
    HasAbs = 0,
    HasLog = 1,
    HasAbs2 = 0,
    HasMin = 0,
    HasMax = 0,
    HasSetLinear = 0
  };
};

template <>
struct unpacket_traits<Packet2cf> {
  typedef std::complex<float> type;
  typedef Packet2cf half;
  typedef Packet4f as_real;
  enum {
    size = 2,
    alignment = Aligned16,
    vectorizable = true,
    masked_load_available = false,
    masked_store_available = false
  };
};

template <>
EIGEN_STRONG_INLINE Packet2cf padd<Packet2cf>(const Packet2cf& a, const Packet2cf& b) {
  return Packet2cf(__lsx_vfadd_s(a.v, b.v));
}
template <>
EIGEN_STRONG_INLINE Packet2cf psub<Packet2cf>(const Packet2cf& a, const Packet2cf& b) {
  return Packet2cf(__lsx_vfsub_s(a.v, b.v));
}

template <>
EIGEN_STRONG_INLINE Packet2cf pnegate(const Packet2cf& a) {
  const uint32_t b[4] = {0x80000000u, 0x80000000u, 0x80000000u, 0x80000000u};
  Packet4i mask = (Packet4i)__lsx_vld(b, 0);
  Packet2cf res;
  res.v = (Packet4f)__lsx_vxor_v((__m128i)a.v, mask);
  return res;
}

template <>
EIGEN_STRONG_INLINE Packet2cf pconj(const Packet2cf& a) {
  const uint32_t b[4] = {0x00000000u, 0x80000000u, 0x00000000u, 0x80000000u};
  Packet4i mask = (__m128i)__lsx_vld(b, 0);
  Packet2cf res;
  res.v = (Packet4f)__lsx_vxor_v((__m128i)a.v, mask);
  return res;
}

template <>
EIGEN_STRONG_INLINE Packet2cf pmul<Packet2cf>(const Packet2cf& a, const Packet2cf& b) {
  Packet4f part0_tmp = (Packet4f)__lsx_vfmul_s(a.v, b.v);
  Packet4f part0 = __lsx_vfsub_s(part0_tmp, (__m128)__lsx_vshuf4i_w(part0_tmp, 0x31));
  Packet4f part1_tmp = __lsx_vfmul_s((__m128)__lsx_vshuf4i_w(a.v, 0xb1), b.v);
  Packet4f part1 = __lsx_vfadd_s(part1_tmp, (__m128)__lsx_vshuf4i_w(part1_tmp, 0x31));
  Packet2cf res;
  res.v = (Packet4f)__lsx_vpackev_w((__m128i)part1, (__m128i)part0);
  return res;
}

template <>
EIGEN_STRONG_INLINE Packet2cf ptrue<Packet2cf>(const Packet2cf& a) {
  return Packet2cf(ptrue(Packet4f(a.v)));
}

template <>
EIGEN_STRONG_INLINE Packet2cf pand<Packet2cf>(const Packet2cf& a, const Packet2cf& b) {
  Packet2cf res;
  res.v = (Packet4f)__lsx_vand_v((__m128i)a.v, (__m128i)b.v);
  return res;
}

template <>
EIGEN_STRONG_INLINE Packet2cf por<Packet2cf>(const Packet2cf& a, const Packet2cf& b) {
  Packet2cf res;
  res.v = (Packet4f)__lsx_vor_v((__m128i)a.v, (__m128i)b.v);
  return res;
}

template <>
EIGEN_STRONG_INLINE Packet2cf pxor<Packet2cf>(const Packet2cf& a, const Packet2cf& b) {
  Packet2cf res;
  res.v = (Packet4f)__lsx_vxor_v((__m128i)a.v, (__m128i)b.v);
  return res;
}

template <>
EIGEN_STRONG_INLINE Packet2cf pandnot<Packet2cf>(const Packet2cf& a, const Packet2cf& b) {
  Packet2cf res;
  res.v = (Packet4f)__lsx_vandn_v((__m128i)b.v, (__m128i)a.v);
  return res;
}

template <>
EIGEN_STRONG_INLINE Packet2cf pload<Packet2cf>(const std::complex<float>* from) {
  EIGEN_DEBUG_ALIGNED_LOAD return Packet2cf(pload<Packet4f>(&numext::real_ref(*from)));
}

template <>
EIGEN_STRONG_INLINE Packet2cf ploadu<Packet2cf>(const std::complex<float>* from) {
  EIGEN_DEBUG_UNALIGNED_LOAD return Packet2cf(ploadu<Packet4f>(&numext::real_ref(*from)));
}

template <>
EIGEN_STRONG_INLINE Packet2cf pset1<Packet2cf>(const std::complex<float>& from) {
  float f0 = from.real(), f1 = from.imag();
  Packet4f re = {f0, f0, f0, f0};
  Packet4f im = {f1, f1, f1, f1};
  return Packet2cf((Packet4f)__lsx_vilvl_w((__m128i)im, (__m128i)re));
}

template <>
EIGEN_STRONG_INLINE Packet2cf ploaddup<Packet2cf>(const std::complex<float>* from) {
  return pset1<Packet2cf>(*from);
}

template <>
EIGEN_STRONG_INLINE void pstore<std::complex<float> >(std::complex<float>* to, const Packet2cf& from) {
  EIGEN_DEBUG_ALIGNED_STORE pstore(&numext::real_ref(*to), Packet4f(from.v));
}

template <>
EIGEN_STRONG_INLINE void pstoreu<std::complex<float> >(std::complex<float>* to, const Packet2cf& from) {
  EIGEN_DEBUG_UNALIGNED_STORE pstoreu(&numext::real_ref(*to), Packet4f(from.v));
}

template <>
EIGEN_DEVICE_FUNC inline Packet2cf pgather<std::complex<float>, Packet2cf>(const std::complex<float>* from,
                                                                           Index stride) {
  Packet2cf res;
  __m128i tmp = __lsx_vldrepl_d(from, 0);
  __m128i tmp1 = __lsx_vldrepl_d(from + stride, 0);
  tmp = __lsx_vilvl_d(tmp1, tmp);
  res.v = (__m128)tmp;
  return res;
}

template <>
EIGEN_DEVICE_FUNC inline void pscatter<std::complex<float>, Packet2cf>(std::complex<float>* to, const Packet2cf& from,
                                                                       Index stride) {
  __lsx_vstelm_d((__m128i)from.v, to, 0, 0);
  __lsx_vstelm_d((__m128i)from.v, to + stride, 0, 1);
}

template <>
EIGEN_STRONG_INLINE void prefetch<std::complex<float> >(const std::complex<float>* addr) {
  __builtin_prefetch(addr);
}

template <>
EIGEN_STRONG_INLINE std::complex<float> pfirst<Packet2cf>(const Packet2cf& a) {
  EIGEN_ALIGN16 std::complex<float> res[2];
  __lsx_vst(a.v, res, 0);
  return res[0];
}

template <>
EIGEN_STRONG_INLINE Packet2cf preverse(const Packet2cf& a) {
  Packet2cf res;
  res.v = (Packet4f)__lsx_vshuf4i_w(a.v, 0x4e);
  return res;
}

template <>
EIGEN_STRONG_INLINE std::complex<float> predux<Packet2cf>(const Packet2cf& a) {
  return pfirst(Packet2cf(__lsx_vfadd_s(a.v, vec4f_movehl(a.v, a.v))));
}

template <>
EIGEN_STRONG_INLINE std::complex<float> predux_mul<Packet2cf>(const Packet2cf& a) {
  return pfirst(pmul(a, Packet2cf(vec4f_movehl(a.v, a.v))));
}

EIGEN_STRONG_INLINE Packet2cf pcplxflip /* <Packet2cf> */ (const Packet2cf& x) {
  return Packet2cf(vec4f_swizzle1(x.v, 1, 0, 3, 2));
}

EIGEN_MAKE_CONJ_HELPER_CPLX_REAL(Packet2cf, Packet4f)

template <>
EIGEN_STRONG_INLINE Packet2cf pdiv<Packet2cf>(const Packet2cf& a, const Packet2cf& b) {
  return pdiv_complex(a, b);
}

template <>
EIGEN_STRONG_INLINE Packet2cf plog<Packet2cf>(const Packet2cf& a) {
  return plog_complex(a);
}

template <>
EIGEN_STRONG_INLINE Packet2cf pzero(const Packet2cf& /* a */) {
  __m128 v = {0.0f, 0.0f, 0.0f, 0.0f};
  return (Packet2cf)v;
}

template <>
EIGEN_STRONG_INLINE Packet2cf pmadd<Packet2cf>(const Packet2cf& a, const Packet2cf& b, const Packet2cf& c) {
  Packet2cf result, t0, t1, t2;
  t1 = pzero(t1);
  t0.v = (__m128)__lsx_vpackev_w((__m128i)a.v, (__m128i)a.v);
  t2.v = __lsx_vfmadd_s(t0.v, b.v, c.v);
  result.v = __lsx_vfadd_s(t2.v, t1.v);
  t1.v = __lsx_vfsub_s(t1.v, a.v);
  t1.v = (__m128)__lsx_vpackod_w((__m128i)a.v, (__m128i)t1.v);
  t2.v = (__m128)__lsx_vshuf4i_w((__m128i)b.v, 0xb1);
  result.v = __lsx_vfmadd_s(t1.v, t2.v, result.v);
  return result;
}

template <>
EIGEN_STRONG_INLINE Packet2cf pexp<Packet2cf>(const Packet2cf& a) {
  return pexp_complex(a);
}

//---------- double ----------
struct Packet1cd {
  EIGEN_STRONG_INLINE Packet1cd() {}
  EIGEN_STRONG_INLINE explicit Packet1cd(const __m128d& a) : v(a) {}
  Packet2d v;
};

template <>
struct packet_traits<std::complex<double> > : default_packet_traits {
  typedef Packet1cd type;
  typedef Packet1cd half;
  enum {
    Vectorizable = 1,
    AlignedOnScalar = 0,
    size = 1,

    HasAdd = 1,
    HasSub = 1,
    HasMul = 1,
    HasDiv = 1,
    HasNegate = 1,
    HasSqrt = 1,
    HasAbs = 0,
    HasLog = 1,
    HasAbs2 = 0,
    HasMin = 0,
    HasMax = 0,
    HasSetLinear = 0
  };
};

template <>
struct unpacket_traits<Packet1cd> {
  typedef std::complex<double> type;
  typedef Packet1cd half;
  typedef Packet2d as_real;
  enum {
    size = 1,
    alignment = Aligned16,
    vectorizable = true,
    masked_load_available = false,
    masked_store_available = false
  };
};

template <>
EIGEN_STRONG_INLINE Packet1cd padd<Packet1cd>(const Packet1cd& a, const Packet1cd& b) {
  return Packet1cd(__lsx_vfadd_d(a.v, b.v));
}
template <>
EIGEN_STRONG_INLINE Packet1cd psub<Packet1cd>(const Packet1cd& a, const Packet1cd& b) {
  return Packet1cd(__lsx_vfsub_d(a.v, b.v));
}
template <>
EIGEN_STRONG_INLINE Packet1cd pnegate(const Packet1cd& a) {
  return Packet1cd(pnegate(Packet2d(a.v)));
}

template <>
EIGEN_STRONG_INLINE Packet1cd pconj(const Packet1cd& a) {
  const uint64_t tmp[2] = {0x0000000000000000u, 0x8000000000000000u};
  __m128i mask = __lsx_vld(tmp, 0);
  Packet1cd res;
  res.v = (Packet2d)__lsx_vxor_v((__m128i)a.v, mask);
  return res;
}

template <>
EIGEN_STRONG_INLINE Packet1cd pmul<Packet1cd>(const Packet1cd& a, const Packet1cd& b) {
  Packet2d tmp_real = __lsx_vfmul_d(a.v, b.v);
  Packet2d real = __lsx_vfsub_d(tmp_real, preverse(tmp_real));

  Packet2d tmp_imag = __lsx_vfmul_d(preverse(a.v), b.v);
  Packet2d imag = (__m128d)__lsx_vfadd_d((__m128d)tmp_imag, preverse(tmp_imag));
  Packet1cd res;
  res.v = (__m128d)__lsx_vilvl_d((__m128i)imag, (__m128i)real);
  return res;
}

template <>
EIGEN_STRONG_INLINE Packet1cd ptrue<Packet1cd>(const Packet1cd& a) {
  return Packet1cd(ptrue(Packet2d(a.v)));
}
template <>
EIGEN_STRONG_INLINE Packet1cd pand<Packet1cd>(const Packet1cd& a, const Packet1cd& b) {
  Packet1cd res;
  res.v = (Packet2d)__lsx_vand_v((__m128i)a.v, (__m128i)b.v);
  return res;
}
template <>
EIGEN_STRONG_INLINE Packet1cd por<Packet1cd>(const Packet1cd& a, const Packet1cd& b) {
  Packet1cd res;
  res.v = (Packet2d)__lsx_vor_v((__m128i)a.v, (__m128i)b.v);
  return res;
}
template <>
EIGEN_STRONG_INLINE Packet1cd pxor<Packet1cd>(const Packet1cd& a, const Packet1cd& b) {
  Packet1cd res;
  res.v = (Packet2d)__lsx_vxor_v((__m128i)a.v, (__m128i)b.v);
  return res;
}
template <>
EIGEN_STRONG_INLINE Packet1cd pandnot<Packet1cd>(const Packet1cd& a, const Packet1cd& b) {
  Packet1cd res;
  res.v = (Packet2d)__lsx_vandn_v((__m128i)b.v, (__m128i)a.v);
  return res;
}

// FIXME force unaligned load, this is a temporary fix
template <>
EIGEN_STRONG_INLINE Packet1cd pload<Packet1cd>(const std::complex<double>* from) {
  EIGEN_DEBUG_ALIGNED_LOAD return Packet1cd(pload<Packet2d>((const double*)from));
}
template <>
EIGEN_STRONG_INLINE Packet1cd ploadu<Packet1cd>(const std::complex<double>* from) {
  EIGEN_DEBUG_UNALIGNED_LOAD return Packet1cd(ploadu<Packet2d>((const double*)from));
}
template <>
EIGEN_STRONG_INLINE Packet1cd
pset1<Packet1cd>(const std::complex<double>& from) { /* here we really have to use unaligned loads :( */
  return ploadu<Packet1cd>(&from);
}

template <>
EIGEN_STRONG_INLINE Packet1cd ploaddup<Packet1cd>(const std::complex<double>* from) {
  return pset1<Packet1cd>(*from);
}

// FIXME force unaligned store, this is a temporary fix
template <>
EIGEN_STRONG_INLINE void pstore<std::complex<double> >(std::complex<double>* to, const Packet1cd& from) {
  EIGEN_DEBUG_ALIGNED_STORE pstore((double*)to, Packet2d(from.v));
}
template <>
EIGEN_STRONG_INLINE void pstoreu<std::complex<double> >(std::complex<double>* to, const Packet1cd& from) {
  EIGEN_DEBUG_UNALIGNED_STORE pstoreu((double*)to, Packet2d(from.v));
}

template <>
EIGEN_STRONG_INLINE void prefetch<std::complex<double> >(const std::complex<double>* addr) {
  __builtin_prefetch(addr);
}

template <>
EIGEN_STRONG_INLINE std::complex<double> pfirst<Packet1cd>(const Packet1cd& a) {
  EIGEN_ALIGN16 double res[2];
  __lsx_vst(a.v, res, 0);
  return std::complex<double>(res[0], res[1]);
}

template <>
EIGEN_STRONG_INLINE Packet1cd preverse(const Packet1cd& a) {
  return a;
}

template <>
EIGEN_STRONG_INLINE std::complex<double> predux<Packet1cd>(const Packet1cd& a) {
  return pfirst(a);
}

template <>
EIGEN_STRONG_INLINE std::complex<double> predux_mul<Packet1cd>(const Packet1cd& a) {
  return pfirst(a);
}

EIGEN_MAKE_CONJ_HELPER_CPLX_REAL(Packet1cd, Packet2d)

template <>
EIGEN_STRONG_INLINE Packet1cd pdiv<Packet1cd>(const Packet1cd& a, const Packet1cd& b) {
  return pdiv_complex(a, b);
}

EIGEN_STRONG_INLINE Packet1cd pcplxflip /* <Packet1cd> */ (const Packet1cd& x) {
  return Packet1cd(preverse(Packet2d(x.v)));
}

EIGEN_DEVICE_FUNC inline void ptranspose(PacketBlock<Packet2cf, 2>& kernel) {
  Packet4f tmp1 = (Packet4f)__lsx_vilvl_w((__m128i)kernel.packet[1].v, (__m128i)kernel.packet[0].v);
  Packet4f tmp2 = (Packet4f)__lsx_vilvh_w((__m128i)kernel.packet[1].v, (__m128i)kernel.packet[0].v);
  kernel.packet[0].v = (Packet4f)__lsx_vshuf4i_w(tmp1, 0xd8);
  kernel.packet[1].v = (Packet4f)__lsx_vshuf4i_w(tmp2, 0xd8);
}

template <>
EIGEN_STRONG_INLINE Packet2cf pcmp_eq(const Packet2cf& a, const Packet2cf& b) {
  Packet4f eq = (Packet4f)__lsx_vfcmp_ceq_s(a.v, b.v);
  return Packet2cf(pand<Packet4f>(eq, vec4f_swizzle1(eq, 1, 0, 3, 2)));
}

template <>
EIGEN_STRONG_INLINE Packet1cd pcmp_eq(const Packet1cd& a, const Packet1cd& b) {
  Packet2d eq = (Packet2d)__lsx_vfcmp_ceq_d(a.v, b.v);
  return Packet1cd(pand<Packet2d>(eq, preverse(eq)));
}

template <>
EIGEN_DEVICE_FUNC inline Packet2cf pselect(const Packet2cf& mask, const Packet2cf& a, const Packet2cf& b) {
  Packet2cf res;
  res.v = (Packet4f)__lsx_vbitsel_v((__m128i)b.v, (__m128i)a.v, (__m128i)mask.v);
  return res;
}

template <>
EIGEN_STRONG_INLINE Packet1cd psqrt<Packet1cd>(const Packet1cd& a) {
  return psqrt_complex<Packet1cd>(a);
}

template <>
EIGEN_STRONG_INLINE Packet2cf psqrt<Packet2cf>(const Packet2cf& a) {
  return psqrt_complex<Packet2cf>(a);
}

template <>
EIGEN_STRONG_INLINE Packet1cd plog<Packet1cd>(const Packet1cd& a) {
  return plog_complex(a);
}

template <>
EIGEN_STRONG_INLINE Packet1cd pzero<Packet1cd>(const Packet1cd& /* a */) {
  __m128d v = {0.0, 0.0};
  return (Packet1cd)v;
}

template <>
EIGEN_STRONG_INLINE Packet1cd pmadd<Packet1cd>(const Packet1cd& a, const Packet1cd& b, const Packet1cd& c) {
  Packet1cd result, t0, t1, t2;
  t1 = pzero(t1);
  t0.v = (__m128d)__lsx_vpackev_d((__m128i)a.v, (__m128i)a.v);
  t2.v = __lsx_vfmadd_d(t0.v, b.v, c.v);
  result.v = __lsx_vfadd_d(t2.v, t1.v);
  t1.v = __lsx_vfsub_d(t1.v, a.v);
  t1.v = (__m128d)__lsx_vpackod_d((__m128i)a.v, (__m128i)t1.v);
  t2.v = (__m128d)__lsx_vshuf4i_d((__m128i)t2.v, (__m128i)b.v, 0xb);
  result.v = __lsx_vfmadd_d(t1.v, t2.v, result.v);
  return result;
}

template <>
EIGEN_DEVICE_FUNC inline Packet1cd pgather<std::complex<double>, Packet1cd>(const std::complex<double>* from,
                                                                            Index /* stride */) {
  Packet1cd res;
  __m128i tmp = __lsx_vld((void*)from, 0);
  res.v = (__m128d)tmp;
  return res;
}

template <>
EIGEN_DEVICE_FUNC inline void pscatter<std::complex<double>, Packet1cd>(std::complex<double>* to, const Packet1cd& from,
                                                                        Index /* stride */) {
  __lsx_vst((__m128i)from.v, (void*)to, 0);
}

EIGEN_STRONG_INLINE void ptranspose(PacketBlock<Packet1cd, 2>& kernel) {
  Packet2d tmp = (__m128d)__lsx_vilvl_d((__m128i)kernel.packet[1].v, (__m128i)kernel.packet[0].v);
  kernel.packet[1].v = (__m128d)__lsx_vilvh_d((__m128i)kernel.packet[1].v, (__m128i)kernel.packet[0].v);
  kernel.packet[0].v = tmp;
}

}  // end namespace internal
}  // end namespace Eigen

#endif  // EIGEN_COMPLEX_LSX_H