xref: /aosp_15_r20/external/eigen/Eigen/src/Core/functors/UnaryFunctors.h (revision bf2c37156dfe67e5dfebd6d394bad8b2ab5804d4)
1 // This file is part of Eigen, a lightweight C++ template library
2 // for linear algebra.
3 //
4 // Copyright (C) 2008-2016 Gael Guennebaud <[email protected]>
5 //
6 // This Source Code Form is subject to the terms of the Mozilla
7 // Public License v. 2.0. If a copy of the MPL was not distributed
8 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
9 
10 #ifndef EIGEN_UNARY_FUNCTORS_H
11 #define EIGEN_UNARY_FUNCTORS_H
12 
13 namespace Eigen {
14 
15 namespace internal {
16 
17 /** \internal
18   * \brief Template functor to compute the opposite of a scalar
19   *
20   * \sa class CwiseUnaryOp, MatrixBase::operator-
21   */
22 template<typename Scalar> struct scalar_opposite_op {
EIGEN_EMPTY_STRUCT_CTORscalar_opposite_op23   EIGEN_EMPTY_STRUCT_CTOR(scalar_opposite_op)
24   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Scalar operator() (const Scalar& a) const { return -a; }
25   template<typename Packet>
packetOpscalar_opposite_op26   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Packet packetOp(const Packet& a) const
27   { return internal::pnegate(a); }
28 };
29 template<typename Scalar>
30 struct functor_traits<scalar_opposite_op<Scalar> >
31 { enum {
32     Cost = NumTraits<Scalar>::AddCost,
33     PacketAccess = packet_traits<Scalar>::HasNegate };
34 };
35 
36 /** \internal
37   * \brief Template functor to compute the absolute value of a scalar
38   *
39   * \sa class CwiseUnaryOp, Cwise::abs
40   */
41 template<typename Scalar> struct scalar_abs_op {
42   EIGEN_EMPTY_STRUCT_CTOR(scalar_abs_op)
43   typedef typename NumTraits<Scalar>::Real result_type;
44   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const result_type operator() (const Scalar& a) const { return numext::abs(a); }
45   template<typename Packet>
46   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Packet packetOp(const Packet& a) const
47   { return internal::pabs(a); }
48 };
49 template<typename Scalar>
50 struct functor_traits<scalar_abs_op<Scalar> >
51 {
52   enum {
53     Cost = NumTraits<Scalar>::AddCost,
54     PacketAccess = packet_traits<Scalar>::HasAbs
55   };
56 };
57 
58 /** \internal
59   * \brief Template functor to compute the score of a scalar, to chose a pivot
60   *
61   * \sa class CwiseUnaryOp
62   */
63 template<typename Scalar> struct scalar_score_coeff_op : scalar_abs_op<Scalar>
64 {
65   typedef void Score_is_abs;
66 };
67 template<typename Scalar>
68 struct functor_traits<scalar_score_coeff_op<Scalar> > : functor_traits<scalar_abs_op<Scalar> > {};
69 
70 /* Avoid recomputing abs when we know the score and they are the same. Not a true Eigen functor.  */
71 template<typename Scalar, typename=void> struct abs_knowing_score
72 {
73   EIGEN_EMPTY_STRUCT_CTOR(abs_knowing_score)
74   typedef typename NumTraits<Scalar>::Real result_type;
75   template<typename Score>
76   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const result_type operator() (const Scalar& a, const Score&) const { return numext::abs(a); }
77 };
78 template<typename Scalar> struct abs_knowing_score<Scalar, typename scalar_score_coeff_op<Scalar>::Score_is_abs>
79 {
80   EIGEN_EMPTY_STRUCT_CTOR(abs_knowing_score)
81   typedef typename NumTraits<Scalar>::Real result_type;
82   template<typename Scal>
83   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const result_type operator() (const Scal&, const result_type& a) const { return a; }
84 };
85 
86 /** \internal
87   * \brief Template functor to compute the squared absolute value of a scalar
88   *
89   * \sa class CwiseUnaryOp, Cwise::abs2
90   */
91 template<typename Scalar> struct scalar_abs2_op {
92   EIGEN_EMPTY_STRUCT_CTOR(scalar_abs2_op)
93   typedef typename NumTraits<Scalar>::Real result_type;
94   EIGEN_DEVICE_FUNC
95   EIGEN_STRONG_INLINE const result_type operator() (const Scalar& a) const { return numext::abs2(a); }
96   template<typename Packet>
97   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Packet packetOp(const Packet& a) const
98   { return internal::pmul(a,a); }
99 };
100 template<typename Scalar>
101 struct functor_traits<scalar_abs2_op<Scalar> >
102 { enum { Cost = NumTraits<Scalar>::MulCost, PacketAccess = packet_traits<Scalar>::HasAbs2 }; };
103 
104 /** \internal
105   * \brief Template functor to compute the conjugate of a complex value
106   *
107   * \sa class CwiseUnaryOp, MatrixBase::conjugate()
108   */
109 template<typename Scalar> struct scalar_conjugate_op {
110   EIGEN_EMPTY_STRUCT_CTOR(scalar_conjugate_op)
111   EIGEN_DEVICE_FUNC
112   EIGEN_STRONG_INLINE const Scalar operator() (const Scalar& a) const { return numext::conj(a); }
113   template<typename Packet>
114   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Packet packetOp(const Packet& a) const { return internal::pconj(a); }
115 };
116 template<typename Scalar>
117 struct functor_traits<scalar_conjugate_op<Scalar> >
118 {
119   enum {
120     Cost = 0,
121     // Yes the cost is zero even for complexes because in most cases for which
122     // the cost is used, conjugation turns to be a no-op. Some examples:
123     //   cost(a*conj(b)) == cost(a*b)
124     //   cost(a+conj(b)) == cost(a+b)
125     //   <etc.
126     // If we don't set it to zero, then:
127     //   A.conjugate().lazyProduct(B.conjugate())
128     // will bake its operands. We definitely don't want that!
129     PacketAccess = packet_traits<Scalar>::HasConj
130   };
131 };
132 
133 /** \internal
134   * \brief Template functor to compute the phase angle of a complex
135   *
136   * \sa class CwiseUnaryOp, Cwise::arg
137   */
138 template<typename Scalar> struct scalar_arg_op {
139   EIGEN_EMPTY_STRUCT_CTOR(scalar_arg_op)
140   typedef typename NumTraits<Scalar>::Real result_type;
141   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const result_type operator() (const Scalar& a) const { return numext::arg(a); }
142   template<typename Packet>
143   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Packet packetOp(const Packet& a) const
144   { return internal::parg(a); }
145 };
146 template<typename Scalar>
147 struct functor_traits<scalar_arg_op<Scalar> >
148 {
149   enum {
150     Cost = NumTraits<Scalar>::IsComplex ? 5 * NumTraits<Scalar>::MulCost : NumTraits<Scalar>::AddCost,
151     PacketAccess = packet_traits<Scalar>::HasArg
152   };
153 };
154 /** \internal
155   * \brief Template functor to cast a scalar to another type
156   *
157   * \sa class CwiseUnaryOp, MatrixBase::cast()
158   */
159 template<typename Scalar, typename NewType>
160 struct scalar_cast_op {
161   EIGEN_EMPTY_STRUCT_CTOR(scalar_cast_op)
162   typedef NewType result_type;
163   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const NewType operator() (const Scalar& a) const { return cast<Scalar, NewType>(a); }
164 };
165 template<typename Scalar, typename NewType>
166 struct functor_traits<scalar_cast_op<Scalar,NewType> >
167 { enum { Cost = is_same<Scalar, NewType>::value ? 0 : NumTraits<NewType>::AddCost, PacketAccess = false }; };
168 
169 /** \internal
170   * \brief Template functor to arithmetically shift a scalar right by a number of bits
171   *
172   * \sa class CwiseUnaryOp, MatrixBase::shift_right()
173   */
174 template<typename Scalar, int N>
175 struct scalar_shift_right_op {
176   EIGEN_EMPTY_STRUCT_CTOR(scalar_shift_right_op)
177 
178   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Scalar operator() (const Scalar& a) const
179   { return a >> N; }
180   template<typename Packet>
181   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Packet packetOp(const Packet& a) const
182   { return internal::parithmetic_shift_right<N>(a); }
183 };
184 template<typename Scalar, int N>
185 struct functor_traits<scalar_shift_right_op<Scalar,N> >
186 { enum { Cost = NumTraits<Scalar>::AddCost, PacketAccess = packet_traits<Scalar>::HasShift }; };
187 
188 /** \internal
189   * \brief Template functor to logically shift a scalar left by a number of bits
190   *
191   * \sa class CwiseUnaryOp, MatrixBase::shift_left()
192   */
193 template<typename Scalar, int N>
194 struct scalar_shift_left_op {
195   EIGEN_EMPTY_STRUCT_CTOR(scalar_shift_left_op)
196 
197   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Scalar operator() (const Scalar& a) const
198   { return a << N; }
199   template<typename Packet>
200   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Packet packetOp(const Packet& a) const
201   { return internal::plogical_shift_left<N>(a); }
202 };
203 template<typename Scalar, int N>
204 struct functor_traits<scalar_shift_left_op<Scalar,N> >
205 { enum { Cost = NumTraits<Scalar>::AddCost, PacketAccess = packet_traits<Scalar>::HasShift }; };
206 
207 /** \internal
208   * \brief Template functor to extract the real part of a complex
209   *
210   * \sa class CwiseUnaryOp, MatrixBase::real()
211   */
212 template<typename Scalar>
213 struct scalar_real_op {
214   EIGEN_EMPTY_STRUCT_CTOR(scalar_real_op)
215   typedef typename NumTraits<Scalar>::Real result_type;
216   EIGEN_DEVICE_FUNC
217   EIGEN_STRONG_INLINE result_type operator() (const Scalar& a) const { return numext::real(a); }
218 };
219 template<typename Scalar>
220 struct functor_traits<scalar_real_op<Scalar> >
221 { enum { Cost = 0, PacketAccess = false }; };
222 
223 /** \internal
224   * \brief Template functor to extract the imaginary part of a complex
225   *
226   * \sa class CwiseUnaryOp, MatrixBase::imag()
227   */
228 template<typename Scalar>
229 struct scalar_imag_op {
230   EIGEN_EMPTY_STRUCT_CTOR(scalar_imag_op)
231   typedef typename NumTraits<Scalar>::Real result_type;
232   EIGEN_DEVICE_FUNC
233   EIGEN_STRONG_INLINE result_type operator() (const Scalar& a) const { return numext::imag(a); }
234 };
235 template<typename Scalar>
236 struct functor_traits<scalar_imag_op<Scalar> >
237 { enum { Cost = 0, PacketAccess = false }; };
238 
239 /** \internal
240   * \brief Template functor to extract the real part of a complex as a reference
241   *
242   * \sa class CwiseUnaryOp, MatrixBase::real()
243   */
244 template<typename Scalar>
245 struct scalar_real_ref_op {
246   EIGEN_EMPTY_STRUCT_CTOR(scalar_real_ref_op)
247   typedef typename NumTraits<Scalar>::Real result_type;
248   EIGEN_DEVICE_FUNC
249   EIGEN_STRONG_INLINE result_type& operator() (const Scalar& a) const { return numext::real_ref(*const_cast<Scalar*>(&a)); }
250 };
251 template<typename Scalar>
252 struct functor_traits<scalar_real_ref_op<Scalar> >
253 { enum { Cost = 0, PacketAccess = false }; };
254 
255 /** \internal
256   * \brief Template functor to extract the imaginary part of a complex as a reference
257   *
258   * \sa class CwiseUnaryOp, MatrixBase::imag()
259   */
260 template<typename Scalar>
261 struct scalar_imag_ref_op {
262   EIGEN_EMPTY_STRUCT_CTOR(scalar_imag_ref_op)
263   typedef typename NumTraits<Scalar>::Real result_type;
264   EIGEN_DEVICE_FUNC
265   EIGEN_STRONG_INLINE result_type& operator() (const Scalar& a) const { return numext::imag_ref(*const_cast<Scalar*>(&a)); }
266 };
267 template<typename Scalar>
268 struct functor_traits<scalar_imag_ref_op<Scalar> >
269 { enum { Cost = 0, PacketAccess = false }; };
270 
271 /** \internal
272   *
273   * \brief Template functor to compute the exponential of a scalar
274   *
275   * \sa class CwiseUnaryOp, Cwise::exp()
276   */
277 template<typename Scalar> struct scalar_exp_op {
278   EIGEN_EMPTY_STRUCT_CTOR(scalar_exp_op)
279   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { return numext::exp(a); }
280   template <typename Packet>
281   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::pexp(a); }
282 };
283 template <typename Scalar>
284 struct functor_traits<scalar_exp_op<Scalar> > {
285   enum {
286     PacketAccess = packet_traits<Scalar>::HasExp,
287     // The following numbers are based on the AVX implementation.
288 #ifdef EIGEN_VECTORIZE_FMA
289     // Haswell can issue 2 add/mul/madd per cycle.
290     Cost =
291     (sizeof(Scalar) == 4
292      // float: 8 pmadd, 4 pmul, 2 padd/psub, 6 other
293      ? (8 * NumTraits<Scalar>::AddCost + 6 * NumTraits<Scalar>::MulCost)
294      // double: 7 pmadd, 5 pmul, 3 padd/psub, 1 div,  13 other
295      : (14 * NumTraits<Scalar>::AddCost +
296         6 * NumTraits<Scalar>::MulCost +
297         scalar_div_cost<Scalar,packet_traits<Scalar>::HasDiv>::value))
298 #else
299     Cost =
300     (sizeof(Scalar) == 4
301      // float: 7 pmadd, 6 pmul, 4 padd/psub, 10 other
302      ? (21 * NumTraits<Scalar>::AddCost + 13 * NumTraits<Scalar>::MulCost)
303      // double: 7 pmadd, 5 pmul, 3 padd/psub, 1 div,  13 other
304      : (23 * NumTraits<Scalar>::AddCost +
305         12 * NumTraits<Scalar>::MulCost +
306         scalar_div_cost<Scalar,packet_traits<Scalar>::HasDiv>::value))
307 #endif
308   };
309 };
310 
311 /** \internal
312   *
313   * \brief Template functor to compute the exponential of a scalar - 1.
314   *
315   * \sa class CwiseUnaryOp, ArrayBase::expm1()
316   */
317 template<typename Scalar> struct scalar_expm1_op {
318   EIGEN_EMPTY_STRUCT_CTOR(scalar_expm1_op)
319   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { return numext::expm1(a); }
320   template <typename Packet>
321   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::pexpm1(a); }
322 };
323 template <typename Scalar>
324 struct functor_traits<scalar_expm1_op<Scalar> > {
325   enum {
326     PacketAccess = packet_traits<Scalar>::HasExpm1,
327     Cost = functor_traits<scalar_exp_op<Scalar> >::Cost // TODO measure cost of expm1
328   };
329 };
330 
331 /** \internal
332   *
333   * \brief Template functor to compute the logarithm of a scalar
334   *
335   * \sa class CwiseUnaryOp, ArrayBase::log()
336   */
337 template<typename Scalar> struct scalar_log_op {
338   EIGEN_EMPTY_STRUCT_CTOR(scalar_log_op)
339   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { return numext::log(a); }
340   template <typename Packet>
341   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::plog(a); }
342 };
343 template <typename Scalar>
344 struct functor_traits<scalar_log_op<Scalar> > {
345   enum {
346     PacketAccess = packet_traits<Scalar>::HasLog,
347     Cost =
348     (PacketAccess
349      // The following numbers are based on the AVX implementation.
350 #ifdef EIGEN_VECTORIZE_FMA
351      // 8 pmadd, 6 pmul, 8 padd/psub, 16 other, can issue 2 add/mul/madd per cycle.
352      ? (20 * NumTraits<Scalar>::AddCost + 7 * NumTraits<Scalar>::MulCost)
353 #else
354      // 8 pmadd, 6 pmul, 8 padd/psub, 20 other
355      ? (36 * NumTraits<Scalar>::AddCost + 14 * NumTraits<Scalar>::MulCost)
356 #endif
357      // Measured cost of std::log.
358      : sizeof(Scalar)==4 ? 40 : 85)
359   };
360 };
361 
362 /** \internal
363   *
364   * \brief Template functor to compute the logarithm of 1 plus a scalar value
365   *
366   * \sa class CwiseUnaryOp, ArrayBase::log1p()
367   */
368 template<typename Scalar> struct scalar_log1p_op {
369   EIGEN_EMPTY_STRUCT_CTOR(scalar_log1p_op)
370   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { return numext::log1p(a); }
371   template <typename Packet>
372   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::plog1p(a); }
373 };
374 template <typename Scalar>
375 struct functor_traits<scalar_log1p_op<Scalar> > {
376   enum {
377     PacketAccess = packet_traits<Scalar>::HasLog1p,
378     Cost = functor_traits<scalar_log_op<Scalar> >::Cost // TODO measure cost of log1p
379   };
380 };
381 
382 /** \internal
383   *
384   * \brief Template functor to compute the base-10 logarithm of a scalar
385   *
386   * \sa class CwiseUnaryOp, Cwise::log10()
387   */
388 template<typename Scalar> struct scalar_log10_op {
389   EIGEN_EMPTY_STRUCT_CTOR(scalar_log10_op)
390   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { EIGEN_USING_STD(log10) return log10(a); }
391   template <typename Packet>
392   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::plog10(a); }
393 };
394 template<typename Scalar>
395 struct functor_traits<scalar_log10_op<Scalar> >
396 { enum { Cost = 5 * NumTraits<Scalar>::MulCost, PacketAccess = packet_traits<Scalar>::HasLog10 }; };
397 
398 /** \internal
399   *
400   * \brief Template functor to compute the base-2 logarithm of a scalar
401   *
402   * \sa class CwiseUnaryOp, Cwise::log2()
403   */
404 template<typename Scalar> struct scalar_log2_op {
405   EIGEN_EMPTY_STRUCT_CTOR(scalar_log2_op)
406   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { return Scalar(EIGEN_LOG2E) * numext::log(a); }
407   template <typename Packet>
408   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::plog2(a); }
409 };
410 template<typename Scalar>
411 struct functor_traits<scalar_log2_op<Scalar> >
412 { enum { Cost = 5 * NumTraits<Scalar>::MulCost, PacketAccess = packet_traits<Scalar>::HasLog }; };
413 
414 /** \internal
415   * \brief Template functor to compute the square root of a scalar
416   * \sa class CwiseUnaryOp, Cwise::sqrt()
417   */
418 template<typename Scalar> struct scalar_sqrt_op {
419   EIGEN_EMPTY_STRUCT_CTOR(scalar_sqrt_op)
420   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { return numext::sqrt(a); }
421   template <typename Packet>
422   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::psqrt(a); }
423 };
424 template <typename Scalar>
425 struct functor_traits<scalar_sqrt_op<Scalar> > {
426   enum {
427 #if EIGEN_FAST_MATH
428     // The following numbers are based on the AVX implementation.
429     Cost = (sizeof(Scalar) == 8 ? 28
430                                 // 4 pmul, 1 pmadd, 3 other
431                                 : (3 * NumTraits<Scalar>::AddCost +
432                                    5 * NumTraits<Scalar>::MulCost)),
433 #else
434     // The following numbers are based on min VSQRT throughput on Haswell.
435     Cost = (sizeof(Scalar) == 8 ? 28 : 14),
436 #endif
437     PacketAccess = packet_traits<Scalar>::HasSqrt
438   };
439 };
440 
441 // Boolean specialization to eliminate -Wimplicit-conversion-floating-point-to-bool warnings.
442 template<> struct scalar_sqrt_op<bool> {
443   EIGEN_EMPTY_STRUCT_CTOR(scalar_sqrt_op)
444   EIGEN_DEPRECATED EIGEN_DEVICE_FUNC inline bool operator() (const bool& a) const { return a; }
445   template <typename Packet>
446   EIGEN_DEPRECATED EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return a; }
447 };
448 template <>
449 struct functor_traits<scalar_sqrt_op<bool> > {
450   enum { Cost = 1, PacketAccess = packet_traits<bool>::Vectorizable };
451 };
452 
453 /** \internal
454   * \brief Template functor to compute the reciprocal square root of a scalar
455   * \sa class CwiseUnaryOp, Cwise::rsqrt()
456   */
457 template<typename Scalar> struct scalar_rsqrt_op {
458   EIGEN_EMPTY_STRUCT_CTOR(scalar_rsqrt_op)
459   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { return numext::rsqrt(a); }
460   template <typename Packet>
461   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::prsqrt(a); }
462 };
463 
464 template<typename Scalar>
465 struct functor_traits<scalar_rsqrt_op<Scalar> >
466 { enum {
467     Cost = 5 * NumTraits<Scalar>::MulCost,
468     PacketAccess = packet_traits<Scalar>::HasRsqrt
469   };
470 };
471 
472 /** \internal
473   * \brief Template functor to compute the cosine of a scalar
474   * \sa class CwiseUnaryOp, ArrayBase::cos()
475   */
476 template<typename Scalar> struct scalar_cos_op {
477   EIGEN_EMPTY_STRUCT_CTOR(scalar_cos_op)
478   EIGEN_DEVICE_FUNC inline Scalar operator() (const Scalar& a) const { return numext::cos(a); }
479   template <typename Packet>
480   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::pcos(a); }
481 };
482 template<typename Scalar>
483 struct functor_traits<scalar_cos_op<Scalar> >
484 {
485   enum {
486     Cost = 5 * NumTraits<Scalar>::MulCost,
487     PacketAccess = packet_traits<Scalar>::HasCos
488   };
489 };
490 
491 /** \internal
492   * \brief Template functor to compute the sine of a scalar
493   * \sa class CwiseUnaryOp, ArrayBase::sin()
494   */
495 template<typename Scalar> struct scalar_sin_op {
496   EIGEN_EMPTY_STRUCT_CTOR(scalar_sin_op)
497   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { return numext::sin(a); }
498   template <typename Packet>
499   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::psin(a); }
500 };
501 template<typename Scalar>
502 struct functor_traits<scalar_sin_op<Scalar> >
503 {
504   enum {
505     Cost = 5 * NumTraits<Scalar>::MulCost,
506     PacketAccess = packet_traits<Scalar>::HasSin
507   };
508 };
509 
510 
511 /** \internal
512   * \brief Template functor to compute the tan of a scalar
513   * \sa class CwiseUnaryOp, ArrayBase::tan()
514   */
515 template<typename Scalar> struct scalar_tan_op {
516   EIGEN_EMPTY_STRUCT_CTOR(scalar_tan_op)
517   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { return numext::tan(a); }
518   template <typename Packet>
519   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::ptan(a); }
520 };
521 template<typename Scalar>
522 struct functor_traits<scalar_tan_op<Scalar> >
523 {
524   enum {
525     Cost = 5 * NumTraits<Scalar>::MulCost,
526     PacketAccess = packet_traits<Scalar>::HasTan
527   };
528 };
529 
530 /** \internal
531   * \brief Template functor to compute the arc cosine of a scalar
532   * \sa class CwiseUnaryOp, ArrayBase::acos()
533   */
534 template<typename Scalar> struct scalar_acos_op {
535   EIGEN_EMPTY_STRUCT_CTOR(scalar_acos_op)
536   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { return numext::acos(a); }
537   template <typename Packet>
538   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::pacos(a); }
539 };
540 template<typename Scalar>
541 struct functor_traits<scalar_acos_op<Scalar> >
542 {
543   enum {
544     Cost = 5 * NumTraits<Scalar>::MulCost,
545     PacketAccess = packet_traits<Scalar>::HasACos
546   };
547 };
548 
549 /** \internal
550   * \brief Template functor to compute the arc sine of a scalar
551   * \sa class CwiseUnaryOp, ArrayBase::asin()
552   */
553 template<typename Scalar> struct scalar_asin_op {
554   EIGEN_EMPTY_STRUCT_CTOR(scalar_asin_op)
555   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { return numext::asin(a); }
556   template <typename Packet>
557   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::pasin(a); }
558 };
559 template<typename Scalar>
560 struct functor_traits<scalar_asin_op<Scalar> >
561 {
562   enum {
563     Cost = 5 * NumTraits<Scalar>::MulCost,
564     PacketAccess = packet_traits<Scalar>::HasASin
565   };
566 };
567 
568 
569 /** \internal
570   * \brief Template functor to compute the atan of a scalar
571   * \sa class CwiseUnaryOp, ArrayBase::atan()
572   */
573 template<typename Scalar> struct scalar_atan_op {
574   EIGEN_EMPTY_STRUCT_CTOR(scalar_atan_op)
575   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { return numext::atan(a); }
576   template <typename Packet>
577   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::patan(a); }
578 };
579 template<typename Scalar>
580 struct functor_traits<scalar_atan_op<Scalar> >
581 {
582   enum {
583     Cost = 5 * NumTraits<Scalar>::MulCost,
584     PacketAccess = packet_traits<Scalar>::HasATan
585   };
586 };
587 
588 /** \internal
589   * \brief Template functor to compute the tanh of a scalar
590   * \sa class CwiseUnaryOp, ArrayBase::tanh()
591   */
592 template <typename Scalar>
593 struct scalar_tanh_op {
594   EIGEN_EMPTY_STRUCT_CTOR(scalar_tanh_op)
595   EIGEN_DEVICE_FUNC inline const Scalar operator()(const Scalar& a) const { return numext::tanh(a); }
596   template <typename Packet>
597   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& x) const { return ptanh(x); }
598 };
599 
600 template <typename Scalar>
601 struct functor_traits<scalar_tanh_op<Scalar> > {
602   enum {
603     PacketAccess = packet_traits<Scalar>::HasTanh,
604     Cost = ( (EIGEN_FAST_MATH && is_same<Scalar,float>::value)
605 // The following numbers are based on the AVX implementation,
606 #ifdef EIGEN_VECTORIZE_FMA
607                 // Haswell can issue 2 add/mul/madd per cycle.
608                 // 9 pmadd, 2 pmul, 1 div, 2 other
609                 ? (2 * NumTraits<Scalar>::AddCost +
610                    6 * NumTraits<Scalar>::MulCost +
611                    scalar_div_cost<Scalar,packet_traits<Scalar>::HasDiv>::value)
612 #else
613                 ? (11 * NumTraits<Scalar>::AddCost +
614                    11 * NumTraits<Scalar>::MulCost +
615                    scalar_div_cost<Scalar,packet_traits<Scalar>::HasDiv>::value)
616 #endif
617                 // This number assumes a naive implementation of tanh
618                 : (6 * NumTraits<Scalar>::AddCost +
619                    3 * NumTraits<Scalar>::MulCost +
620                    2 * scalar_div_cost<Scalar,packet_traits<Scalar>::HasDiv>::value +
621                    functor_traits<scalar_exp_op<Scalar> >::Cost))
622   };
623 };
624 
625 #if EIGEN_HAS_CXX11_MATH
626 /** \internal
627   * \brief Template functor to compute the atanh of a scalar
628   * \sa class CwiseUnaryOp, ArrayBase::atanh()
629   */
630 template <typename Scalar>
631 struct scalar_atanh_op {
632   EIGEN_EMPTY_STRUCT_CTOR(scalar_atanh_op)
633   EIGEN_DEVICE_FUNC inline const Scalar operator()(const Scalar& a) const { return numext::atanh(a); }
634 };
635 
636 template <typename Scalar>
637 struct functor_traits<scalar_atanh_op<Scalar> > {
638   enum { Cost = 5 * NumTraits<Scalar>::MulCost, PacketAccess = false };
639 };
640 #endif
641 
642 /** \internal
643   * \brief Template functor to compute the sinh of a scalar
644   * \sa class CwiseUnaryOp, ArrayBase::sinh()
645   */
646 template<typename Scalar> struct scalar_sinh_op {
647   EIGEN_EMPTY_STRUCT_CTOR(scalar_sinh_op)
648   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { return numext::sinh(a); }
649   template <typename Packet>
650   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::psinh(a); }
651 };
652 template<typename Scalar>
653 struct functor_traits<scalar_sinh_op<Scalar> >
654 {
655   enum {
656     Cost = 5 * NumTraits<Scalar>::MulCost,
657     PacketAccess = packet_traits<Scalar>::HasSinh
658   };
659 };
660 
661 #if EIGEN_HAS_CXX11_MATH
662 /** \internal
663   * \brief Template functor to compute the asinh of a scalar
664   * \sa class CwiseUnaryOp, ArrayBase::asinh()
665   */
666 template <typename Scalar>
667 struct scalar_asinh_op {
668   EIGEN_EMPTY_STRUCT_CTOR(scalar_asinh_op)
669   EIGEN_DEVICE_FUNC inline const Scalar operator()(const Scalar& a) const { return numext::asinh(a); }
670 };
671 
672 template <typename Scalar>
673 struct functor_traits<scalar_asinh_op<Scalar> > {
674   enum { Cost = 5 * NumTraits<Scalar>::MulCost, PacketAccess = false };
675 };
676 #endif
677 
678 /** \internal
679   * \brief Template functor to compute the cosh of a scalar
680   * \sa class CwiseUnaryOp, ArrayBase::cosh()
681   */
682 template<typename Scalar> struct scalar_cosh_op {
683   EIGEN_EMPTY_STRUCT_CTOR(scalar_cosh_op)
684   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const { return numext::cosh(a); }
685   template <typename Packet>
686   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::pcosh(a); }
687 };
688 template<typename Scalar>
689 struct functor_traits<scalar_cosh_op<Scalar> >
690 {
691   enum {
692     Cost = 5 * NumTraits<Scalar>::MulCost,
693     PacketAccess = packet_traits<Scalar>::HasCosh
694   };
695 };
696 
697 #if EIGEN_HAS_CXX11_MATH
698 /** \internal
699   * \brief Template functor to compute the acosh of a scalar
700   * \sa class CwiseUnaryOp, ArrayBase::acosh()
701   */
702 template <typename Scalar>
703 struct scalar_acosh_op {
704   EIGEN_EMPTY_STRUCT_CTOR(scalar_acosh_op)
705   EIGEN_DEVICE_FUNC inline const Scalar operator()(const Scalar& a) const { return numext::acosh(a); }
706 };
707 
708 template <typename Scalar>
709 struct functor_traits<scalar_acosh_op<Scalar> > {
710   enum { Cost = 5 * NumTraits<Scalar>::MulCost, PacketAccess = false };
711 };
712 #endif
713 
714 /** \internal
715   * \brief Template functor to compute the inverse of a scalar
716   * \sa class CwiseUnaryOp, Cwise::inverse()
717   */
718 template<typename Scalar>
719 struct scalar_inverse_op {
720   EIGEN_EMPTY_STRUCT_CTOR(scalar_inverse_op)
721   EIGEN_DEVICE_FUNC inline Scalar operator() (const Scalar& a) const { return Scalar(1)/a; }
722   template<typename Packet>
723   EIGEN_DEVICE_FUNC inline const Packet packetOp(const Packet& a) const
724   { return internal::pdiv(pset1<Packet>(Scalar(1)),a); }
725 };
726 template <typename Scalar>
727 struct functor_traits<scalar_inverse_op<Scalar> > {
728   enum {
729     PacketAccess = packet_traits<Scalar>::HasDiv,
730     Cost = scalar_div_cost<Scalar, PacketAccess>::value
731   };
732 };
733 
734 /** \internal
735   * \brief Template functor to compute the square of a scalar
736   * \sa class CwiseUnaryOp, Cwise::square()
737   */
738 template<typename Scalar>
739 struct scalar_square_op {
740   EIGEN_EMPTY_STRUCT_CTOR(scalar_square_op)
741   EIGEN_DEVICE_FUNC inline Scalar operator() (const Scalar& a) const { return a*a; }
742   template<typename Packet>
743   EIGEN_DEVICE_FUNC inline const Packet packetOp(const Packet& a) const
744   { return internal::pmul(a,a); }
745 };
746 template<typename Scalar>
747 struct functor_traits<scalar_square_op<Scalar> >
748 { enum { Cost = NumTraits<Scalar>::MulCost, PacketAccess = packet_traits<Scalar>::HasMul }; };
749 
750 // Boolean specialization to avoid -Wint-in-bool-context warnings on GCC.
751 template<>
752 struct scalar_square_op<bool> {
753   EIGEN_EMPTY_STRUCT_CTOR(scalar_square_op)
754   EIGEN_DEPRECATED EIGEN_DEVICE_FUNC inline bool operator() (const bool& a) const { return a; }
755   template<typename Packet>
756   EIGEN_DEPRECATED EIGEN_DEVICE_FUNC inline const Packet packetOp(const Packet& a) const
757   { return a; }
758 };
759 template<>
760 struct functor_traits<scalar_square_op<bool> >
761 { enum { Cost = 0, PacketAccess = packet_traits<bool>::Vectorizable }; };
762 
763 /** \internal
764   * \brief Template functor to compute the cube of a scalar
765   * \sa class CwiseUnaryOp, Cwise::cube()
766   */
767 template<typename Scalar>
768 struct scalar_cube_op {
769   EIGEN_EMPTY_STRUCT_CTOR(scalar_cube_op)
770   EIGEN_DEVICE_FUNC inline Scalar operator() (const Scalar& a) const { return a*a*a; }
771   template<typename Packet>
772   EIGEN_DEVICE_FUNC inline const Packet packetOp(const Packet& a) const
773   { return internal::pmul(a,pmul(a,a)); }
774 };
775 template<typename Scalar>
776 struct functor_traits<scalar_cube_op<Scalar> >
777 { enum { Cost = 2*NumTraits<Scalar>::MulCost, PacketAccess = packet_traits<Scalar>::HasMul }; };
778 
779 // Boolean specialization to avoid -Wint-in-bool-context warnings on GCC.
780 template<>
781 struct scalar_cube_op<bool> {
782   EIGEN_EMPTY_STRUCT_CTOR(scalar_cube_op)
783   EIGEN_DEPRECATED EIGEN_DEVICE_FUNC inline bool operator() (const bool& a) const { return a; }
784   template<typename Packet>
785   EIGEN_DEPRECATED EIGEN_DEVICE_FUNC inline const Packet packetOp(const Packet& a) const
786   { return a; }
787 };
788 template<>
789 struct functor_traits<scalar_cube_op<bool> >
790 { enum { Cost = 0, PacketAccess = packet_traits<bool>::Vectorizable }; };
791 
792 /** \internal
793   * \brief Template functor to compute the rounded value of a scalar
794   * \sa class CwiseUnaryOp, ArrayBase::round()
795   */
796 template<typename Scalar> struct scalar_round_op {
797   EIGEN_EMPTY_STRUCT_CTOR(scalar_round_op)
798   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Scalar operator() (const Scalar& a) const { return numext::round(a); }
799   template <typename Packet>
800   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::pround(a); }
801 };
802 template<typename Scalar>
803 struct functor_traits<scalar_round_op<Scalar> >
804 {
805   enum {
806     Cost = NumTraits<Scalar>::MulCost,
807     PacketAccess = packet_traits<Scalar>::HasRound
808   };
809 };
810 
811 /** \internal
812   * \brief Template functor to compute the floor of a scalar
813   * \sa class CwiseUnaryOp, ArrayBase::floor()
814   */
815 template<typename Scalar> struct scalar_floor_op {
816   EIGEN_EMPTY_STRUCT_CTOR(scalar_floor_op)
817   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Scalar operator() (const Scalar& a) const { return numext::floor(a); }
818   template <typename Packet>
819   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::pfloor(a); }
820 };
821 template<typename Scalar>
822 struct functor_traits<scalar_floor_op<Scalar> >
823 {
824   enum {
825     Cost = NumTraits<Scalar>::MulCost,
826     PacketAccess = packet_traits<Scalar>::HasFloor
827   };
828 };
829 
830 /** \internal
831   * \brief Template functor to compute the rounded (with current rounding mode)  value of a scalar
832   * \sa class CwiseUnaryOp, ArrayBase::rint()
833   */
834 template<typename Scalar> struct scalar_rint_op {
835   EIGEN_EMPTY_STRUCT_CTOR(scalar_rint_op)
836   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Scalar operator() (const Scalar& a) const { return numext::rint(a); }
837   template <typename Packet>
838   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::print(a); }
839 };
840 template<typename Scalar>
841 struct functor_traits<scalar_rint_op<Scalar> >
842 {
843   enum {
844     Cost = NumTraits<Scalar>::MulCost,
845     PacketAccess = packet_traits<Scalar>::HasRint
846   };
847 };
848 
849 /** \internal
850   * \brief Template functor to compute the ceil of a scalar
851   * \sa class CwiseUnaryOp, ArrayBase::ceil()
852   */
853 template<typename Scalar> struct scalar_ceil_op {
854   EIGEN_EMPTY_STRUCT_CTOR(scalar_ceil_op)
855   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const Scalar operator() (const Scalar& a) const { return numext::ceil(a); }
856   template <typename Packet>
857   EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::pceil(a); }
858 };
859 template<typename Scalar>
860 struct functor_traits<scalar_ceil_op<Scalar> >
861 {
862   enum {
863     Cost = NumTraits<Scalar>::MulCost,
864     PacketAccess = packet_traits<Scalar>::HasCeil
865   };
866 };
867 
868 /** \internal
869   * \brief Template functor to compute whether a scalar is NaN
870   * \sa class CwiseUnaryOp, ArrayBase::isnan()
871   */
872 template<typename Scalar> struct scalar_isnan_op {
873   EIGEN_EMPTY_STRUCT_CTOR(scalar_isnan_op)
874   typedef bool result_type;
875   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE result_type operator() (const Scalar& a) const {
876 #if defined(SYCL_DEVICE_ONLY)
877     return numext::isnan(a);
878 #else
879     return (numext::isnan)(a);
880 #endif
881   }
882 };
883 template<typename Scalar>
884 struct functor_traits<scalar_isnan_op<Scalar> >
885 {
886   enum {
887     Cost = NumTraits<Scalar>::MulCost,
888     PacketAccess = false
889   };
890 };
891 
892 /** \internal
893   * \brief Template functor to check whether a scalar is +/-inf
894   * \sa class CwiseUnaryOp, ArrayBase::isinf()
895   */
896 template<typename Scalar> struct scalar_isinf_op {
897   EIGEN_EMPTY_STRUCT_CTOR(scalar_isinf_op)
898   typedef bool result_type;
899   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE result_type operator() (const Scalar& a) const {
900 #if defined(SYCL_DEVICE_ONLY)
901     return numext::isinf(a);
902 #else
903     return (numext::isinf)(a);
904 #endif
905   }
906 };
907 template<typename Scalar>
908 struct functor_traits<scalar_isinf_op<Scalar> >
909 {
910   enum {
911     Cost = NumTraits<Scalar>::MulCost,
912     PacketAccess = false
913   };
914 };
915 
916 /** \internal
917   * \brief Template functor to check whether a scalar has a finite value
918   * \sa class CwiseUnaryOp, ArrayBase::isfinite()
919   */
920 template<typename Scalar> struct scalar_isfinite_op {
921   EIGEN_EMPTY_STRUCT_CTOR(scalar_isfinite_op)
922   typedef bool result_type;
923   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE result_type operator() (const Scalar& a) const {
924 #if defined(SYCL_DEVICE_ONLY)
925     return numext::isfinite(a);
926 #else
927     return (numext::isfinite)(a);
928 #endif
929   }
930 };
931 template<typename Scalar>
932 struct functor_traits<scalar_isfinite_op<Scalar> >
933 {
934   enum {
935     Cost = NumTraits<Scalar>::MulCost,
936     PacketAccess = false
937   };
938 };
939 
940 /** \internal
941   * \brief Template functor to compute the logical not of a boolean
942   *
943   * \sa class CwiseUnaryOp, ArrayBase::operator!
944   */
945 template<typename Scalar> struct scalar_boolean_not_op {
946   EIGEN_EMPTY_STRUCT_CTOR(scalar_boolean_not_op)
947   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE bool operator() (const bool& a) const { return !a; }
948 };
949 template<typename Scalar>
950 struct functor_traits<scalar_boolean_not_op<Scalar> > {
951   enum {
952     Cost = NumTraits<bool>::AddCost,
953     PacketAccess = false
954   };
955 };
956 
957 /** \internal
958   * \brief Template functor to compute the signum of a scalar
959   * \sa class CwiseUnaryOp, Cwise::sign()
960   */
961 template<typename Scalar,bool is_complex=(NumTraits<Scalar>::IsComplex!=0), bool is_integer=(NumTraits<Scalar>::IsInteger!=0) > struct scalar_sign_op;
962 template<typename Scalar>
963 struct scalar_sign_op<Scalar, false, true> {
964   EIGEN_EMPTY_STRUCT_CTOR(scalar_sign_op)
965   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const
966   {
967       return Scalar( (a>Scalar(0)) - (a<Scalar(0)) );
968   }
969   //TODO
970   //template <typename Packet>
971   //EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::psign(a); }
972 };
973 
974 template<typename Scalar>
975 struct scalar_sign_op<Scalar, false, false> {
976   EIGEN_EMPTY_STRUCT_CTOR(scalar_sign_op)
977   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const
978   {
979     return (numext::isnan)(a) ? a : Scalar( (a>Scalar(0)) - (a<Scalar(0)) );
980   }
981   //TODO
982   //template <typename Packet>
983   //EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::psign(a); }
984 };
985 
986 template<typename Scalar, bool is_integer>
987 struct scalar_sign_op<Scalar,true, is_integer> {
988   EIGEN_EMPTY_STRUCT_CTOR(scalar_sign_op)
989   EIGEN_DEVICE_FUNC inline const Scalar operator() (const Scalar& a) const
990   {
991     typedef typename NumTraits<Scalar>::Real real_type;
992     real_type aa = numext::abs(a);
993     if (aa==real_type(0))
994       return Scalar(0);
995     aa = real_type(1)/aa;
996     return Scalar(a.real()*aa, a.imag()*aa );
997   }
998   //TODO
999   //template <typename Packet>
1000   //EIGEN_DEVICE_FUNC inline Packet packetOp(const Packet& a) const { return internal::psign(a); }
1001 };
1002 template<typename Scalar>
1003 struct functor_traits<scalar_sign_op<Scalar> >
1004 { enum {
1005     Cost =
1006         NumTraits<Scalar>::IsComplex
1007         ? ( 8*NumTraits<Scalar>::MulCost  ) // roughly
1008         : ( 3*NumTraits<Scalar>::AddCost),
1009     PacketAccess = packet_traits<Scalar>::HasSign
1010   };
1011 };
1012 
1013 /** \internal
1014   * \brief Template functor to compute the logistic function of a scalar
1015   * \sa class CwiseUnaryOp, ArrayBase::logistic()
1016   */
1017 template <typename T>
1018 struct scalar_logistic_op {
1019   EIGEN_EMPTY_STRUCT_CTOR(scalar_logistic_op)
1020   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE T operator()(const T& x) const {
1021     return packetOp(x);
1022   }
1023 
1024   template <typename Packet> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
1025   Packet packetOp(const Packet& x) const {
1026     const Packet one = pset1<Packet>(T(1));
1027     return pdiv(one, padd(one, pexp(pnegate(x))));
1028   }
1029 };
1030 
1031 #ifndef EIGEN_GPU_COMPILE_PHASE
1032 /** \internal
1033   * \brief Template specialization of the logistic function for float.
1034   *
1035   *  Uses just a 9/10-degree rational interpolant which
1036   *  interpolates 1/(1+exp(-x)) - 0.5 up to a couple of ulps in the range
1037   *  [-9, 18]. Below -9 we use the more accurate approximation
1038   *  1/(1+exp(-x)) ~= exp(x), and above 18 the logistic function is 1 withing
1039   *  one ulp. The shifted logistic is interpolated because it was easier to
1040   *  make the fit converge.
1041   *
1042   */
1043 template <>
1044 struct scalar_logistic_op<float> {
1045   EIGEN_EMPTY_STRUCT_CTOR(scalar_logistic_op)
1046   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE float operator()(const float& x) const {
1047     return packetOp(x);
1048   }
1049 
1050   template <typename Packet> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
1051   Packet packetOp(const Packet& _x) const {
1052     const Packet cutoff_lower = pset1<Packet>(-9.f);
1053     const Packet lt_mask = pcmp_lt<Packet>(_x, cutoff_lower);
1054     const bool any_small = predux_any(lt_mask);
1055 
1056     // The upper cut-off is the smallest x for which the rational approximation evaluates to 1.
1057     // Choosing this value saves us a few instructions clamping the results at the end.
1058 #ifdef EIGEN_VECTORIZE_FMA
1059     const Packet cutoff_upper = pset1<Packet>(15.7243833541870117f);
1060 #else
1061     const Packet cutoff_upper = pset1<Packet>(15.6437711715698242f);
1062 #endif
1063     const Packet x = pmin(_x, cutoff_upper);
1064 
1065     // The monomial coefficients of the numerator polynomial (odd).
1066     const Packet alpha_1 = pset1<Packet>(2.48287947061529e-01f);
1067     const Packet alpha_3 = pset1<Packet>(8.51377133304701e-03f);
1068     const Packet alpha_5 = pset1<Packet>(6.08574864600143e-05f);
1069     const Packet alpha_7 = pset1<Packet>(1.15627324459942e-07f);
1070     const Packet alpha_9 = pset1<Packet>(4.37031012579801e-11f);
1071 
1072     // The monomial coefficients of the denominator polynomial (even).
1073     const Packet beta_0 = pset1<Packet>(9.93151921023180e-01f);
1074     const Packet beta_2 = pset1<Packet>(1.16817656904453e-01f);
1075     const Packet beta_4 = pset1<Packet>(1.70198817374094e-03f);
1076     const Packet beta_6 = pset1<Packet>(6.29106785017040e-06f);
1077     const Packet beta_8 = pset1<Packet>(5.76102136993427e-09f);
1078     const Packet beta_10 = pset1<Packet>(6.10247389755681e-13f);
1079 
1080     // Since the polynomials are odd/even, we need x^2.
1081     const Packet x2 = pmul(x, x);
1082 
1083     // Evaluate the numerator polynomial p.
1084     Packet p = pmadd(x2, alpha_9, alpha_7);
1085     p = pmadd(x2, p, alpha_5);
1086     p = pmadd(x2, p, alpha_3);
1087     p = pmadd(x2, p, alpha_1);
1088     p = pmul(x, p);
1089 
1090     // Evaluate the denominator polynomial q.
1091     Packet q = pmadd(x2, beta_10, beta_8);
1092     q = pmadd(x2, q, beta_6);
1093     q = pmadd(x2, q, beta_4);
1094     q = pmadd(x2, q, beta_2);
1095     q = pmadd(x2, q, beta_0);
1096     // Divide the numerator by the denominator and shift it up.
1097     const Packet logistic = padd(pdiv(p, q), pset1<Packet>(0.5f));
1098     if (EIGEN_PREDICT_FALSE(any_small)) {
1099       const Packet exponential = pexp(_x);
1100       return pselect(lt_mask, exponential, logistic);
1101     } else {
1102       return logistic;
1103     }
1104   }
1105 };
1106 #endif  // #ifndef EIGEN_GPU_COMPILE_PHASE
1107 
1108 template <typename T>
1109 struct functor_traits<scalar_logistic_op<T> > {
1110   enum {
1111     // The cost estimate for float here here is for the common(?) case where
1112     // all arguments are greater than -9.
1113     Cost = scalar_div_cost<T, packet_traits<T>::HasDiv>::value +
1114            (internal::is_same<T, float>::value
1115                 ? NumTraits<T>::AddCost * 15 + NumTraits<T>::MulCost * 11
1116                 : NumTraits<T>::AddCost * 2 +
1117                       functor_traits<scalar_exp_op<T> >::Cost),
1118     PacketAccess =
1119         packet_traits<T>::HasAdd && packet_traits<T>::HasDiv &&
1120         (internal::is_same<T, float>::value
1121              ? packet_traits<T>::HasMul && packet_traits<T>::HasMax &&
1122                    packet_traits<T>::HasMin
1123              : packet_traits<T>::HasNegate && packet_traits<T>::HasExp)
1124   };
1125 };
1126 
1127 } // end namespace internal
1128 
1129 } // end namespace Eigen
1130 
1131 #endif // EIGEN_FUNCTORS_H
1132