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#ifndef GMX_SIMD_IMPL_X86_AVX_128_FMA_SIMD4_DOUBLE_H
#define GMX_SIMD_IMPL_X86_AVX_128_FMA_SIMD4_DOUBLE_H

#include "config.h"

#include <immintrin.h>
#include <x86intrin.h>

#include <cassert>
#include <cstddef>

namespace gmx
{

class Simd4Double
{
public:
    Simd4Double() {}

    Simd4Double(double d) : simdInternal_(_mm256_set1_pd(d)) {}

    // Internal utility constructor to simplify return statements
    Simd4Double(__m256d simd) : simdInternal_(simd) {}

    __m256d simdInternal_;
};

class Simd4DBool
{
public:
    Simd4DBool() {}

    //! \brief Construct from scalar bool
    Simd4DBool(bool b) : simdInternal_(_mm256_castsi256_pd(_mm256_set1_epi32(b ? 0xFFFFFFFF : 0)))
    {
    }

    // Internal utility constructor to simplify return statements
    Simd4DBool(__m256d simd) : simdInternal_(simd) {}

    __m256d simdInternal_;
};

static inline Simd4Double gmx_simdcall load4(const double* m)
{
    assert(size_t(m) % 32 == 0);
    return { _mm256_load_pd(m) };
}

static inline void gmx_simdcall store4(double* m, Simd4Double a)
{
    assert(size_t(m) % 32 == 0);
    _mm256_store_pd(m, a.simdInternal_);
}

static inline Simd4Double gmx_simdcall load4U(const double* m)
{
    return { _mm256_loadu_pd(m) };
}

static inline void gmx_simdcall store4U(double* m, Simd4Double a)
{
    _mm256_storeu_pd(m, a.simdInternal_);
}

static inline Simd4Double gmx_simdcall simd4SetZeroD()
{
    return { _mm256_setzero_pd() };
}

static inline Simd4Double gmx_simdcall operator&(Simd4Double a, Simd4Double b)
{
    return { _mm256_and_pd(a.simdInternal_, b.simdInternal_) };
}

static inline Simd4Double gmx_simdcall andNot(Simd4Double a, Simd4Double b)
{
    return { _mm256_andnot_pd(a.simdInternal_, b.simdInternal_) };
}

static inline Simd4Double gmx_simdcall operator|(Simd4Double a, Simd4Double b)
{
    return { _mm256_or_pd(a.simdInternal_, b.simdInternal_) };
}

static inline Simd4Double gmx_simdcall operator^(Simd4Double a, Simd4Double b)
{
    return { _mm256_xor_pd(a.simdInternal_, b.simdInternal_) };
}

static inline Simd4Double gmx_simdcall operator+(Simd4Double a, Simd4Double b)
{
    return { _mm256_add_pd(a.simdInternal_, b.simdInternal_) };
}

static inline Simd4Double gmx_simdcall operator-(Simd4Double a, Simd4Double b)
{
    return { _mm256_sub_pd(a.simdInternal_, b.simdInternal_) };
}

static inline Simd4Double gmx_simdcall operator-(Simd4Double x)
{
    return { _mm256_xor_pd(x.simdInternal_, _mm256_set1_pd(GMX_DOUBLE_NEGZERO)) };
}

static inline Simd4Double gmx_simdcall operator*(Simd4Double a, Simd4Double b)
{
    return { _mm256_mul_pd(a.simdInternal_, b.simdInternal_) };
}

static inline Simd4Double gmx_simdcall fma(Simd4Double a, Simd4Double b, Simd4Double c)
{
    return { _mm256_macc_pd(a.simdInternal_, b.simdInternal_, c.simdInternal_) };
}

static inline Simd4Double gmx_simdcall fms(Simd4Double a, Simd4Double b, Simd4Double c)
{
    return { _mm256_msub_pd(a.simdInternal_, b.simdInternal_, c.simdInternal_) };
}

static inline Simd4Double gmx_simdcall fnma(Simd4Double a, Simd4Double b, Simd4Double c)
{
    return { _mm256_nmacc_pd(a.simdInternal_, b.simdInternal_, c.simdInternal_) };
}

static inline Simd4Double gmx_simdcall fnms(Simd4Double a, Simd4Double b, Simd4Double c)
{
    return { _mm256_nmsub_pd(a.simdInternal_, b.simdInternal_, c.simdInternal_) };
}

static inline Simd4Double gmx_simdcall rsqrt(Simd4Double x)
{
    return { _mm256_cvtps_pd(_mm_rsqrt_ps(_mm256_cvtpd_ps(x.simdInternal_))) };
}

static inline Simd4Double gmx_simdcall abs(Simd4Double x)
{
    return { _mm256_andnot_pd(_mm256_set1_pd(GMX_DOUBLE_NEGZERO), x.simdInternal_) };
}

static inline Simd4Double gmx_simdcall max(Simd4Double a, Simd4Double b)
{
    return { _mm256_max_pd(a.simdInternal_, b.simdInternal_) };
}

static inline Simd4Double gmx_simdcall min(Simd4Double a, Simd4Double b)
{
    return { _mm256_min_pd(a.simdInternal_, b.simdInternal_) };
}

static inline Simd4Double gmx_simdcall round(Simd4Double x)
{
    return { _mm256_round_pd(x.simdInternal_, _MM_FROUND_NINT) };
}

static inline Simd4Double gmx_simdcall trunc(Simd4Double x)
{
    return { _mm256_round_pd(x.simdInternal_, _MM_FROUND_TRUNC) };
}

static inline double gmx_simdcall dotProduct(Simd4Double a, Simd4Double b)
{
    __m128d tmp1, tmp2;
    a.simdInternal_ = _mm256_mul_pd(a.simdInternal_, b.simdInternal_);
    tmp1            = _mm256_castpd256_pd128(a.simdInternal_);
    tmp2            = _mm256_extractf128_pd(a.simdInternal_, 0x1);

    tmp1 = _mm_add_pd(tmp1, _mm_permute_pd(tmp1, _MM_SHUFFLE2(0, 1)));
    tmp1 = _mm_add_pd(tmp1, tmp2);
    return *reinterpret_cast<double*>(&tmp1);
}

static inline void gmx_simdcall transpose(Simd4Double* v0, Simd4Double* v1, Simd4Double* v2, Simd4Double* v3)
{
    __m256d t1, t2, t3, t4;
    t1                = _mm256_unpacklo_pd(v0->simdInternal_, v1->simdInternal_);
    t2                = _mm256_unpackhi_pd(v0->simdInternal_, v1->simdInternal_);
    t3                = _mm256_unpacklo_pd(v2->simdInternal_, v3->simdInternal_);
    t4                = _mm256_unpackhi_pd(v2->simdInternal_, v3->simdInternal_);
    v0->simdInternal_ = _mm256_permute2f128_pd(t1, t3, 0x20);
    v1->simdInternal_ = _mm256_permute2f128_pd(t2, t4, 0x20);
    v2->simdInternal_ = _mm256_permute2f128_pd(t1, t3, 0x31);
    v3->simdInternal_ = _mm256_permute2f128_pd(t2, t4, 0x31);
}

static inline Simd4DBool gmx_simdcall operator==(Simd4Double a, Simd4Double b)
{
    return { _mm256_cmp_pd(a.simdInternal_, b.simdInternal_, _CMP_EQ_OQ) };
}

static inline Simd4DBool gmx_simdcall operator!=(Simd4Double a, Simd4Double b)
{
    return { _mm256_cmp_pd(a.simdInternal_, b.simdInternal_, _CMP_NEQ_OQ) };
}

static inline Simd4DBool gmx_simdcall operator<(Simd4Double a, Simd4Double b)
{
    return { _mm256_cmp_pd(a.simdInternal_, b.simdInternal_, _CMP_LT_OQ) };
}

static inline Simd4DBool gmx_simdcall operator<=(Simd4Double a, Simd4Double b)
{
    return { _mm256_cmp_pd(a.simdInternal_, b.simdInternal_, _CMP_LE_OQ) };
}

static inline Simd4DBool gmx_simdcall operator&&(Simd4DBool a, Simd4DBool b)
{
    return { _mm256_and_pd(a.simdInternal_, b.simdInternal_) };
}

static inline Simd4DBool gmx_simdcall operator||(Simd4DBool a, Simd4DBool b)
{
    return { _mm256_or_pd(a.simdInternal_, b.simdInternal_) };
}

static inline bool gmx_simdcall anyTrue(Simd4DBool a)
{
    return _mm256_movemask_pd(a.simdInternal_) != 0;
}

static inline Simd4Double gmx_simdcall selectByMask(Simd4Double a, Simd4DBool mask)
{
    return { _mm256_and_pd(a.simdInternal_, mask.simdInternal_) };
}

static inline Simd4Double gmx_simdcall selectByNotMask(Simd4Double a, Simd4DBool mask)
{
    return { _mm256_andnot_pd(mask.simdInternal_, a.simdInternal_) };
}

static inline Simd4Double gmx_simdcall blend(Simd4Double a, Simd4Double b, Simd4DBool sel)
{
    return { _mm256_blendv_pd(a.simdInternal_, b.simdInternal_, sel.simdInternal_) };
}

static inline double gmx_simdcall reduce(Simd4Double a)
{
    __m128d a0, a1;
    /* test with shuffle & add as an alternative to hadd later */
    a.simdInternal_ = _mm256_hadd_pd(a.simdInternal_, a.simdInternal_);
    a0              = _mm256_castpd256_pd128(a.simdInternal_);
    a1              = _mm256_extractf128_pd(a.simdInternal_, 0x1);
    a0              = _mm_add_sd(a0, a1);
    return *reinterpret_cast<double*>(&a0);
}

} // namespace gmx

#endif // GMX_SIMD_IMPL_X86_AVX_128_FMA_SIMD4_DOUBLE_H
