test/packetmath_test_shared.h

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2008-2009 Gael Guennebaud <gael.guennebaud@inria.fr>
// Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1@gmail.com>
//
// 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/.
// SPDX-License-Identifier: MPL-2.0

#ifndef EIGEN_TEST_PACKETMATH_TEST_SHARED_H
#define EIGEN_TEST_PACKETMATH_TEST_SHARED_H

#include "main.h"
#include <typeinfo>

#if defined __GNUC__ && __GNUC__ >= 6
#pragma GCC diagnostic ignored "-Wignored-attributes"
#endif
// using namespace Eigen;

bool g_first_pass = true;

namespace Eigen {

namespace test {

template <typename T, std::enable_if_t<NumTraits<T>::IsSigned && NumTraits<T>::IsInteger, bool> = true>
T negate(const T& x) {
  // `-x` is UB at the minimum representable value; go through the unsigned type instead, the
  // same way the unsigned overload below does. This wraps to match what the vectorized
  // `pnegate` actually computes there.
  using UnsignedT = typename std::make_unsigned<T>::type;
  return static_cast<T>(UnsignedT(0) - static_cast<UnsignedT>(x));
}

template <typename T, std::enable_if_t<NumTraits<T>::IsSigned && !NumTraits<T>::IsInteger, bool> = true>
T negate(const T& x) {
  return -x;
}

template <typename T, std::enable_if_t<!NumTraits<T>::IsSigned, bool> = true>
T negate(const T& x) {
  return T(0) - x;
}

template <typename T>
Map<const Array<unsigned char, sizeof(T), 1> > bits(const T& x) {
  return Map<const Array<unsigned char, sizeof(T), 1> >(reinterpret_cast<const unsigned char*>(&x));
}

template <typename T>
bool biteq(T a, T b) {
  return (bits(a) == bits(b)).all();
}

// NOTE: we disable inlining for this function to workaround a GCC issue when using -O3 and the i387 FPU.
template <typename Scalar>
EIGEN_DONT_INLINE bool isApproxAbs(const Scalar& a, const Scalar& b, const typename NumTraits<Scalar>::Real& refvalue) {
  return internal::isMuchSmallerThan(a - b, refvalue);
}

template <typename Scalar>
inline void print_mismatch(const Scalar* ref, const Scalar* vec, int size) {
  std::cout << "ref: [" << Map<const Matrix<Scalar, 1, Dynamic> >(ref, size) << "]"
            << " != vec: [" << Map<const Matrix<Scalar, 1, Dynamic> >(vec, size) << "]\n";
}

template <typename Scalar>
bool areApproxAbs(const Scalar* a, const Scalar* b, int size, const typename NumTraits<Scalar>::Real& refvalue) {
  for (int i = 0; i < size; ++i) {
    if (!isApproxAbs(a[i], b[i], refvalue)) {
      print_mismatch(a, b, size);
      std::cout << std::setprecision(16) << "Values differ in position " << i << ": " << a[i] << " vs " << b[i]
                << std::endl;
      return false;
    }
  }
  return true;
}

template <typename Scalar>
bool areApprox(const Scalar* a, const Scalar* b, int size) {
  for (int i = 0; i < size; ++i) {
    if (numext::not_equal_strict(a[i], b[i]) && !internal::isApprox(a[i], b[i]) &&
        !((numext::isnan)(a[i]) && (numext::isnan)(b[i]))) {
      print_mismatch(a, b, size);
      std::cout << std::setprecision(16) << "Values differ in position " << i << ": " << a[i] << " vs " << b[i]
                << std::endl;
      return false;
    }
  }
  return true;
}

template <typename Scalar>
bool areEqual(const Scalar* a, const Scalar* b, int size) {
  for (int i = 0; i < size; ++i) {
    if (numext::not_equal_strict(a[i], b[i]) && !((numext::isnan)(a[i]) && (numext::isnan)(b[i]))) {
      print_mismatch(a, b, size);
      std::cout << std::setprecision(16) << "Values differ in position " << i << ": " << a[i] << " vs " << b[i]
                << std::endl;
      return false;
    }
  }
  return true;
}

// Checks that each lane of `data` is a full bit mask: all bits set when `zero_mask[i]` is false, all
// bits cleared when it is true. Packet comparisons must return all-ones masks on true lanes so that
// the result can be consumed bitwise (pselect, pand, pandnot, ...); a lane that is merely nonzero
// (e.g. a NaN produced by an arithmetic float-to-half conversion of the mask) is not enough.
template <typename Scalar>
bool areFullBitMasks(const Scalar* data, const bool* zero_mask, int size) {
  for (int i = 0; i < size; ++i) {
    const unsigned char expected = zero_mask[i] ? 0x00 : 0xff;
    if (!(bits(data[i]) == expected).all()) {
      std::cout << "Mask lane " << i << " should be all-" << (zero_mask[i] ? "zero" : "one")
                << " bits, got bytes:" << std::hex;
      for (std::size_t k = 0; k < sizeof(Scalar); ++k) std::cout << " 0x" << static_cast<int>(bits(data[i])[k]);
      std::cout << std::dec << std::endl;
      return false;
    }
  }
  return true;
}

// print_mismatch for a buffer of any length: the eight lanes around position `at`.
template <typename Scalar>
inline void print_mismatch_window(const Scalar* ref, const Scalar* vec, int size, int at) {
  const int window = 8;
  const int begin = (std::max)(0, at - window / 2);
  const int end = (std::min)(size, begin + window);
  std::cout << "lanes [" << begin << ", " << end << ") ";
  print_mismatch(ref + begin, vec + begin, end - begin);
}

// Bitwise equality lane by lane; with `nan_is_nan`, two NaNs match whatever their payloads. Use it where a
// contract fixes the result bit for bit (loads and stores, bit operations, correctly rounded arithmetic, the sign of
// a zero) and areEqual's value comparison would pass +0 for -0.
template <typename Scalar>
bool areEqualBits(const Scalar* a, const Scalar* b, int size, bool nan_is_nan = true) {
  for (int i = 0; i < size; ++i) {
    const bool both_nan = nan_is_nan && (numext::isnan)(a[i]) && (numext::isnan)(b[i]);
    if (!both_nan && !biteq(a[i], b[i])) {
      print_mismatch_window(a, b, size, i);
      std::cout << std::setprecision(16) << "Bits differ in position " << i << ": " << a[i] << " vs " << b[i]
                << std::endl;
      return false;
    }
  }
  return true;
}

// The position of x among the values of its type: the sign-magnitude bit pattern folded onto a monotone integer
// line, so that adjacent representable values are one apart, +0 and -0 coincide, and the infinities sit at the ends.
template <typename Scalar>
typename numext::get_integer_by_size<sizeof(Scalar)>::signed_type ordered_position(Scalar x) {
  using Bits = typename numext::get_integer_by_size<sizeof(Scalar)>::signed_type;
  const Bits bits = numext::bit_cast<Bits>(x);
  return bits < 0 ? Bits((std::numeric_limits<Bits>::min)() - bits) : bits;
}

// Distance in units in the last place between two values of the same floating-point type. Two NaNs are zero apart,
// a NaN and a number as far apart as possible. (test/ulp_accuracy measures signed errors with its own fold, which
// maps -0 below +0 and treats infinities as incomparable; the budgets it reports are not this distance.)
template <typename Scalar>
uint64_t ulp_distance(Scalar a, Scalar b) {
  const bool a_nan = (numext::isnan)(a);
  const bool b_nan = (numext::isnan)(b);
  if (a_nan || b_nan) return (a_nan && b_nan) ? 0 : (std::numeric_limits<uint64_t>::max)();
  const int64_t pa = static_cast<int64_t>(ordered_position(a));
  const int64_t pb = static_cast<int64_t>(ordered_position(b));
  return pa > pb ? uint64_t(pa) - uint64_t(pb) : uint64_t(pb) - uint64_t(pa);
}

template <typename Scalar>
bool areWithinUlps(const Scalar* ref, const Scalar* vec, int size, uint64_t max_ulps) {
  for (int i = 0; i < size; ++i) {
    const uint64_t distance = ulp_distance(ref[i], vec[i]);
    if (distance > max_ulps) {
      print_mismatch_window(ref, vec, size, i);
      std::cout << std::setprecision(16) << "Values differ in position " << i << " by " << distance << " ulps (budget "
                << max_ulps << "): " << ref[i] << " vs " << vec[i] << std::endl;
      return false;
    }
  }
  return true;
}

template <typename Scalar>
bool areApprox(const Scalar* a, const Scalar* b, int size, const typename NumTraits<Scalar>::Real& precision) {
  for (int i = 0; i < size; ++i) {
    if (numext::not_equal_strict(a[i], b[i]) && !internal::isApprox(a[i], b[i], precision) &&
        !((numext::isnan)(a[i]) && (numext::isnan)(b[i]))) {
      print_mismatch(a, b, size);
      std::cout << std::setprecision(16) << "Values differ in position " << i << ": " << a[i] << " vs " << b[i]
                << std::endl;
      return false;
    }
  }
  return true;
}

#define CHECK_CWISE1(REFOP, POP)                                   \
  {                                                                \
    for (int i = 0; i < PacketSize; ++i) ref[i] = REFOP(data1[i]); \
    internal::pstore(data2, POP(internal::pload<Packet>(data1)));  \
    VERIFY(test::areApprox(ref, data2, PacketSize) && #POP);       \
  }

#define CHECK_CWISE1_MASK(REFOP, POP)                                \
  {                                                                  \
    bool ref_mask[PacketSize] = {};                                  \
    bool data_mask[PacketSize] = {};                                 \
    internal::pstore(data2, POP(internal::pload<Packet>(data1)));    \
    for (int i = 0; i < PacketSize; ++i) {                           \
      ref_mask[i] = numext::is_exactly_zero(REFOP(data1[i]));        \
      data_mask[i] = numext::is_exactly_zero(data2[i]);              \
    }                                                                \
    VERIFY(test::areEqual(ref_mask, data_mask, PacketSize) && #POP); \
  }

#define CHECK_CWISE2_MASK(REFOP, POP)                                                                          \
  {                                                                                                            \
    bool ref_mask[PacketSize] = {};                                                                            \
    bool data_mask[PacketSize] = {};                                                                           \
    internal::pstore(data2, POP(internal::pload<Packet>(data1), internal::pload<Packet>(data1 + PacketSize))); \
    for (int i = 0; i < PacketSize; ++i) {                                                                     \
      ref_mask[i] = numext::is_exactly_zero(REFOP(data1[i], data1[i + PacketSize]));                           \
      data_mask[i] = numext::is_exactly_zero(data2[i]);                                                        \
    }                                                                                                          \
    VERIFY(test::areEqual(ref_mask, data_mask, PacketSize) && #POP);                                           \
    /* Vectorized comparisons must produce all-ones bit masks on true lanes. Scalar fallbacks return */        \
    /* Scalar(1) and bool packets store `true` (loading 0xff into a bool is UB), so those are exempt. */       \
    if (internal::unpacket_traits<Packet>::vectorizable && !std::is_same<Scalar, bool>::value) {               \
      VERIFY(test::areFullBitMasks(data2, ref_mask, PacketSize) && #POP);                                      \
    }                                                                                                          \
  }

// Checks component-wise for input of size N. All of data1, data2, and ref
// should have size at least ceil(N/PacketSize)*PacketSize to avoid memory
// access errors.
#define CHECK_CWISE1_N(REFOP, POP, N)                                                                             \
  {                                                                                                               \
    for (int i = 0; i < N; ++i) ref[i] = REFOP(data1[i]);                                                         \
    for (int j = 0; j < N; j += PacketSize) internal::pstore(data2 + j, POP(internal::pload<Packet>(data1 + j))); \
    VERIFY(test::areApprox(ref, data2, N) && #POP);                                                               \
  }

// Checks component-wise for input of complex type of size N. The real and
// the imaginary part are compared separately, with 1ULP relaxed condition
// for the imaginary part. All of data1 data2, ref, realdata1 and realref
// should have size at least ceil(N/PacketSize)*PacketSize to avoid
// memory access errors.
#define CHECK_CWISE1_IM1ULP_N(REFOP, POP, N)                                            \
  {                                                                                     \
    RealScalar eps_1ulp = RealScalar(1e1) * std::numeric_limits<RealScalar>::epsilon(); \
    for (int j = 0; j < N; j += PacketSize)                                             \
      internal::pstore(data2 + j, internal::plog(internal::pload<Packet>(data1 + j)));  \
    for (int i = 0; i < N; ++i) {                                                       \
      ref[i] = REFOP(data1[i]);                                                         \
      realref[i] = ref[i].imag();                                                       \
      realdata[i] = data2[i].imag();                                                    \
    }                                                                                   \
    VERIFY(test::areApprox(realdata, realref, N, eps_1ulp));                            \
    for (int i = 0; i < N; ++i) {                                                       \
      realdata[i] = data2[i].real();                                                    \
      realref[i] = ref[i].real();                                                       \
    }                                                                                   \
    VERIFY(test::areApprox(realdata, realref, N));                                      \
  }

template <bool Cond, typename Packet>
struct packet_helper {
  template <typename T>
  inline Packet load(const T* from) const {
    return internal::pload<Packet>(from);
  }

  template <typename T>
  inline Packet loadu(const T* from) const {
    return internal::ploadu<Packet>(from);
  }

  template <typename T>
  inline Packet load(const T* from, unsigned long long umask) const {
    using UMaskType = typename numext::get_integer_by_size<internal::plain_enum_max(
        internal::unpacket_traits<Packet>::size / CHAR_BIT, 1)>::unsigned_type;
    return internal::ploadu<Packet>(from, static_cast<UMaskType>(umask));
  }

  template <typename T>
  inline void store(T* to, const Packet& x) const {
    internal::pstore(to, x);
  }

  template <typename T>
  inline void store(T* to, const Packet& x, unsigned long long umask) const {
    using UMaskType = typename numext::get_integer_by_size<internal::plain_enum_max(
        internal::unpacket_traits<Packet>::size / CHAR_BIT, 1)>::unsigned_type;
    internal::pstoreu(to, x, static_cast<UMaskType>(umask));
  }

  template <typename T>
  inline Packet& forward_reference(Packet& packet, T& /*scalar*/) const {
    return packet;
  }
};

template <typename Packet>
struct packet_helper<false, Packet> {
  template <typename T>
  inline T load(const T* from) const {
    return *from;
  }

  template <typename T>
  inline T loadu(const T* from) const {
    return *from;
  }

  template <typename T>
  inline T load(const T* from, unsigned long long) const {
    return *from;
  }

  template <typename T>
  inline void store(T* to, const T& x) const {
    *to = x;
  }

  template <typename T>
  inline void store(T* to, const T& x, unsigned long long) const {
    *to = x;
  }

  template <typename T>
  inline T& forward_reference(Packet& /*packet*/, T& scalar) const {
    return scalar;
  }
};

#define CHECK_CWISE1_IF(COND, REFOP, POP)                                  \
  if (COND) {                                                              \
    test::packet_helper<COND, Packet> h;                                   \
    for (int i = 0; i < PacketSize; ++i) ref[i] = Scalar(REFOP(data1[i])); \
    h.store(data2, POP(h.load(data1)));                                    \
    VERIFY(test::areApprox(ref, data2, PacketSize) && #POP);               \
  }

#define CHECK_CWISE1_EXACT_IF(COND, REFOP, POP)                            \
  if (COND) {                                                              \
    test::packet_helper<COND, Packet> h;                                   \
    for (int i = 0; i < PacketSize; ++i) ref[i] = Scalar(REFOP(data1[i])); \
    h.store(data2, POP(h.load(data1)));                                    \
    VERIFY(test::areEqual(ref, data2, PacketSize) && #POP);                \
  }

#define CHECK_CWISE2_IF(COND, REFOP, POP)                                                         \
  if (COND) {                                                                                     \
    test::packet_helper<COND, Packet> h;                                                          \
    for (int i = 0; i < PacketSize; ++i) ref[i] = Scalar(REFOP(data1[i], data1[i + PacketSize])); \
    h.store(data2, POP(h.load(data1), h.load(data1 + PacketSize)));                               \
    VERIFY(test::areApprox(ref, data2, PacketSize) && #POP);                                      \
  }

// One input, one output by reference.
#define CHECK_CWISE1_BYREF1_IF(COND, REFOP, POP)                                                \
  if (COND) {                                                                                   \
    test::packet_helper<COND, Packet> h;                                                        \
    for (int i = 0; i < PacketSize; ++i) ref[i] = Scalar(REFOP(data1[i], ref[i + PacketSize])); \
    Packet pout;                                                                                \
    Scalar sout;                                                                                \
    h.store(data2, POP(h.load(data1), h.forward_reference(pout, sout)));                        \
    h.store(data2 + PacketSize, h.forward_reference(pout, sout));                               \
    VERIFY(test::areApprox(ref, data2, 2 * PacketSize) && #POP);                                \
  }

#define CHECK_CWISE3_IF(COND, REFOP, POP)                                                           \
  if (COND) {                                                                                       \
    test::packet_helper<COND, Packet> h;                                                            \
    for (int i = 0; i < PacketSize; ++i)                                                            \
      ref[i] = Scalar(REFOP(data1[i], data1[i + PacketSize], data1[i + 2 * PacketSize]));           \
    h.store(data2, POP(h.load(data1), h.load(data1 + PacketSize), h.load(data1 + 2 * PacketSize))); \
    VERIFY(test::areApprox(ref, data2, PacketSize) && #POP);                                        \
  }

// Specialize the runall struct in your test file by defining run().
template <typename Scalar, typename PacketType, bool IsComplex = NumTraits<Scalar>::IsComplex,
          bool IsInteger = NumTraits<Scalar>::IsInteger>
struct runall;

template <typename Scalar, typename PacketType = typename internal::packet_traits<Scalar>::type,
          bool Vectorized = internal::packet_traits<Scalar>::Vectorizable,
          bool HasHalf = !std::is_same<typename internal::unpacket_traits<PacketType>::half, PacketType>::value>
struct runner;

template <typename Scalar, typename PacketType>
struct runner<Scalar, PacketType, true, true> {
  static void run() {
    runall<Scalar, PacketType>::run();
    runner<Scalar, typename internal::unpacket_traits<PacketType>::half>::run();
  }
};

template <typename Scalar, typename PacketType>
struct runner<Scalar, PacketType, true, false> {
  static void run() { runall<Scalar, PacketType>::run(); }
};

template <typename Scalar, typename PacketType>
struct runner<Scalar, PacketType, false, false> {
  static void run() { runall<Scalar, PacketType>::run(); }
};

}  // namespace test
}  // namespace Eigen

#endif  // EIGEN_TEST_PACKETMATH_TEST_SHARED_H