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complex_cmath.h (12559B) - Raw


      1 //===------------------------- __complex_cmath.h --------------------------===//
      2 //
      3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
      4 // See https://llvm.org/LICENSE.txt for license information.
      5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
      6 //
      7 //===----------------------------------------------------------------------===//
      8 //
      9 // std::complex header copied from the libcxx source and simplified for use in
     10 // OpenMP target offload regions.
     11 //
     12 //===----------------------------------------------------------------------===//
     13 
     14 #ifndef _OPENMP
     15 #error "This file is for OpenMP compilation only."
     16 #endif
     17 
     18 #ifndef __cplusplus
     19 #error "This file is for C++ compilation only."
     20 #endif
     21 
     22 #ifndef _LIBCPP_COMPLEX
     23 #define _LIBCPP_COMPLEX
     24 
     25 #include <cmath>
     26 #include <type_traits>
     27 
     28 #define __DEVICE__ static constexpr __attribute__((nothrow))
     29 
     30 namespace std {
     31 
     32 // abs
     33 
     34 template <class _Tp> __DEVICE__ _Tp abs(const std::complex<_Tp> &__c) {
     35   return hypot(__c.real(), __c.imag());
     36 }
     37 
     38 // arg
     39 
     40 template <class _Tp> __DEVICE__ _Tp arg(const std::complex<_Tp> &__c) {
     41   return atan2(__c.imag(), __c.real());
     42 }
     43 
     44 template <class _Tp>
     45 typename enable_if<is_integral<_Tp>::value || is_same<_Tp, double>::value,
     46                    double>::type
     47 arg(_Tp __re) {
     48   return atan2(0., __re);
     49 }
     50 
     51 template <class _Tp>
     52 typename enable_if<is_same<_Tp, float>::value, float>::type arg(_Tp __re) {
     53   return atan2f(0.F, __re);
     54 }
     55 
     56 // norm
     57 
     58 template <class _Tp> __DEVICE__ _Tp norm(const std::complex<_Tp> &__c) {
     59   if (std::isinf(__c.real()))
     60     return abs(__c.real());
     61   if (std::isinf(__c.imag()))
     62     return abs(__c.imag());
     63   return __c.real() * __c.real() + __c.imag() * __c.imag();
     64 }
     65 
     66 // conj
     67 #ifdef _GLIBCXX20_CONSTEXPR
     68 #define CXX20_CONSTEXPR_DEVICE __DEVICE__
     69 #else
     70 #define CXX20_CONSTEXPR_DEVICE
     71 #endif
     72 template <class _Tp>
     73 CXX20_CONSTEXPR_DEVICE std::complex<_Tp> conj(const std::complex<_Tp> &__c) {
     74   return std::complex<_Tp>(__c.real(), -__c.imag());
     75 }
     76 
     77 // proj
     78 
     79 template <class _Tp> std::complex<_Tp> proj(const std::complex<_Tp> &__c) {
     80   std::complex<_Tp> __r = __c;
     81   if (std::isinf(__c.real()) || std::isinf(__c.imag()))
     82     __r = std::complex<_Tp>(INFINITY, copysign(_Tp(0), __c.imag()));
     83   return __r;
     84 }
     85 
     86 // polar
     87 
     88 template <class _Tp>
     89 complex<_Tp> polar(const _Tp &__rho, const _Tp &__theta = _Tp()) {
     90   if (std::isnan(__rho) || signbit(__rho))
     91     return std::complex<_Tp>(_Tp(NAN), _Tp(NAN));
     92   if (std::isnan(__theta)) {
     93     if (std::isinf(__rho))
     94       return std::complex<_Tp>(__rho, __theta);
     95     return std::complex<_Tp>(__theta, __theta);
     96   }
     97   if (std::isinf(__theta)) {
     98     if (std::isinf(__rho))
     99       return std::complex<_Tp>(__rho, _Tp(NAN));
    100     return std::complex<_Tp>(_Tp(NAN), _Tp(NAN));
    101   }
    102   _Tp __x = __rho * cos(__theta);
    103   if (std::isnan(__x))
    104     __x = 0;
    105   _Tp __y = __rho * sin(__theta);
    106   if (std::isnan(__y))
    107     __y = 0;
    108   return std::complex<_Tp>(__x, __y);
    109 }
    110 
    111 // log
    112 
    113 template <class _Tp> std::complex<_Tp> log(const std::complex<_Tp> &__x) {
    114   return std::complex<_Tp>(log(abs(__x)), arg(__x));
    115 }
    116 
    117 // log10
    118 
    119 template <class _Tp> std::complex<_Tp> log10(const std::complex<_Tp> &__x) {
    120   return log(__x) / log(_Tp(10));
    121 }
    122 
    123 // sqrt
    124 
    125 template <class _Tp>
    126 __DEVICE__ std::complex<_Tp> sqrt(const std::complex<_Tp> &__x) {
    127   if (std::isinf(__x.imag()))
    128     return std::complex<_Tp>(_Tp(INFINITY), __x.imag());
    129   if (std::isinf(__x.real())) {
    130     if (__x.real() > _Tp(0))
    131       return std::complex<_Tp>(__x.real(), std::isnan(__x.imag())
    132                                                ? __x.imag()
    133                                                : copysign(_Tp(0), __x.imag()));
    134     return std::complex<_Tp>(std::isnan(__x.imag()) ? __x.imag() : _Tp(0),
    135                              copysign(__x.real(), __x.imag()));
    136   }
    137   return polar(sqrt(abs(__x)), arg(__x) / _Tp(2));
    138 }
    139 
    140 // exp
    141 
    142 template <class _Tp>
    143 __DEVICE__ std::complex<_Tp> exp(const std::complex<_Tp> &__x) {
    144   _Tp __i = __x.imag();
    145   if (std::isinf(__x.real())) {
    146     if (__x.real() < _Tp(0)) {
    147       if (!std::isfinite(__i))
    148         __i = _Tp(1);
    149     } else if (__i == 0 || !std::isfinite(__i)) {
    150       if (std::isinf(__i))
    151         __i = _Tp(NAN);
    152       return std::complex<_Tp>(__x.real(), __i);
    153     }
    154   } else if (std::isnan(__x.real()) && __x.imag() == 0)
    155     return __x;
    156   _Tp __e = exp(__x.real());
    157   return std::complex<_Tp>(__e * cos(__i), __e * sin(__i));
    158 }
    159 
    160 // pow
    161 
    162 template <class _Tp>
    163 std::complex<_Tp> pow(const std::complex<_Tp> &__x,
    164                       const std::complex<_Tp> &__y) {
    165   return exp(__y * log(__x));
    166 }
    167 
    168 // __sqr, computes pow(x, 2)
    169 
    170 template <class _Tp> std::complex<_Tp> __sqr(const std::complex<_Tp> &__x) {
    171   return std::complex<_Tp>((__x.real() - __x.imag()) *
    172                                (__x.real() + __x.imag()),
    173                            _Tp(2) * __x.real() * __x.imag());
    174 }
    175 
    176 // asinh
    177 
    178 template <class _Tp>
    179 __DEVICE__ std::complex<_Tp> asinh(const std::complex<_Tp> &__x) {
    180   const _Tp __pi(atan2(+0., -0.));
    181   if (std::isinf(__x.real())) {
    182     if (std::isnan(__x.imag()))
    183       return __x;
    184     if (std::isinf(__x.imag()))
    185       return std::complex<_Tp>(__x.real(),
    186                                copysign(__pi * _Tp(0.25), __x.imag()));
    187     return std::complex<_Tp>(__x.real(), copysign(_Tp(0), __x.imag()));
    188   }
    189   if (std::isnan(__x.real())) {
    190     if (std::isinf(__x.imag()))
    191       return std::complex<_Tp>(__x.imag(), __x.real());
    192     if (__x.imag() == 0)
    193       return __x;
    194     return std::complex<_Tp>(__x.real(), __x.real());
    195   }
    196   if (std::isinf(__x.imag()))
    197     return std::complex<_Tp>(copysign(__x.imag(), __x.real()),
    198                              copysign(__pi / _Tp(2), __x.imag()));
    199   std::complex<_Tp> __z = log(__x + sqrt(__sqr(__x) + _Tp(1)));
    200   return std::complex<_Tp>(copysign(__z.real(), __x.real()),
    201                            copysign(__z.imag(), __x.imag()));
    202 }
    203 
    204 // acosh
    205 
    206 template <class _Tp>
    207 __DEVICE__ std::complex<_Tp> acosh(const std::complex<_Tp> &__x) {
    208   const _Tp __pi(atan2(+0., -0.));
    209   if (std::isinf(__x.real())) {
    210     if (std::isnan(__x.imag()))
    211       return std::complex<_Tp>(abs(__x.real()), __x.imag());
    212     if (std::isinf(__x.imag())) {
    213       if (__x.real() > 0)
    214         return std::complex<_Tp>(__x.real(),
    215                                  copysign(__pi * _Tp(0.25), __x.imag()));
    216       else
    217         return std::complex<_Tp>(-__x.real(),
    218                                  copysign(__pi * _Tp(0.75), __x.imag()));
    219     }
    220     if (__x.real() < 0)
    221       return std::complex<_Tp>(-__x.real(), copysign(__pi, __x.imag()));
    222     return std::complex<_Tp>(__x.real(), copysign(_Tp(0), __x.imag()));
    223   }
    224   if (std::isnan(__x.real())) {
    225     if (std::isinf(__x.imag()))
    226       return std::complex<_Tp>(abs(__x.imag()), __x.real());
    227     return std::complex<_Tp>(__x.real(), __x.real());
    228   }
    229   if (std::isinf(__x.imag()))
    230     return std::complex<_Tp>(abs(__x.imag()),
    231                              copysign(__pi / _Tp(2), __x.imag()));
    232   std::complex<_Tp> __z = log(__x + sqrt(__sqr(__x) - _Tp(1)));
    233   return std::complex<_Tp>(copysign(__z.real(), _Tp(0)),
    234                            copysign(__z.imag(), __x.imag()));
    235 }
    236 
    237 // atanh
    238 
    239 template <class _Tp>
    240 __DEVICE__ std::complex<_Tp> atanh(const std::complex<_Tp> &__x) {
    241   const _Tp __pi(atan2(+0., -0.));
    242   if (std::isinf(__x.imag())) {
    243     return std::complex<_Tp>(copysign(_Tp(0), __x.real()),
    244                              copysign(__pi / _Tp(2), __x.imag()));
    245   }
    246   if (std::isnan(__x.imag())) {
    247     if (std::isinf(__x.real()) || __x.real() == 0)
    248       return std::complex<_Tp>(copysign(_Tp(0), __x.real()), __x.imag());
    249     return std::complex<_Tp>(__x.imag(), __x.imag());
    250   }
    251   if (std::isnan(__x.real())) {
    252     return std::complex<_Tp>(__x.real(), __x.real());
    253   }
    254   if (std::isinf(__x.real())) {
    255     return std::complex<_Tp>(copysign(_Tp(0), __x.real()),
    256                              copysign(__pi / _Tp(2), __x.imag()));
    257   }
    258   if (abs(__x.real()) == _Tp(1) && __x.imag() == _Tp(0)) {
    259     return std::complex<_Tp>(copysign(_Tp(INFINITY), __x.real()),
    260                              copysign(_Tp(0), __x.imag()));
    261   }
    262   std::complex<_Tp> __z = log((_Tp(1) + __x) / (_Tp(1) - __x)) / _Tp(2);
    263   return std::complex<_Tp>(copysign(__z.real(), __x.real()),
    264                            copysign(__z.imag(), __x.imag()));
    265 }
    266 
    267 // sinh
    268 
    269 template <class _Tp>
    270 __DEVICE__ std::complex<_Tp> sinh(const std::complex<_Tp> &__x) {
    271   if (std::isinf(__x.real()) && !std::isfinite(__x.imag()))
    272     return std::complex<_Tp>(__x.real(), _Tp(NAN));
    273   if (__x.real() == 0 && !std::isfinite(__x.imag()))
    274     return std::complex<_Tp>(__x.real(), _Tp(NAN));
    275   if (__x.imag() == 0 && !std::isfinite(__x.real()))
    276     return __x;
    277   return std::complex<_Tp>(sinh(__x.real()) * cos(__x.imag()),
    278                            cosh(__x.real()) * sin(__x.imag()));
    279 }
    280 
    281 // cosh
    282 
    283 template <class _Tp>
    284 __DEVICE__ std::complex<_Tp> cosh(const std::complex<_Tp> &__x) {
    285   if (std::isinf(__x.real()) && !std::isfinite(__x.imag()))
    286     return std::complex<_Tp>(abs(__x.real()), _Tp(NAN));
    287   if (__x.real() == 0 && !std::isfinite(__x.imag()))
    288     return std::complex<_Tp>(_Tp(NAN), __x.real());
    289   if (__x.real() == 0 && __x.imag() == 0)
    290     return std::complex<_Tp>(_Tp(1), __x.imag());
    291   if (__x.imag() == 0 && !std::isfinite(__x.real()))
    292     return std::complex<_Tp>(abs(__x.real()), __x.imag());
    293   return std::complex<_Tp>(cosh(__x.real()) * cos(__x.imag()),
    294                            sinh(__x.real()) * sin(__x.imag()));
    295 }
    296 
    297 // tanh
    298 
    299 template <class _Tp>
    300 __DEVICE__ std::complex<_Tp> tanh(const std::complex<_Tp> &__x) {
    301   if (std::isinf(__x.real())) {
    302     if (!std::isfinite(__x.imag()))
    303       return std::complex<_Tp>(_Tp(1), _Tp(0));
    304     return std::complex<_Tp>(_Tp(1),
    305                              copysign(_Tp(0), sin(_Tp(2) * __x.imag())));
    306   }
    307   if (std::isnan(__x.real()) && __x.imag() == 0)
    308     return __x;
    309   _Tp __2r(_Tp(2) * __x.real());
    310   _Tp __2i(_Tp(2) * __x.imag());
    311   _Tp __d(cosh(__2r) + cos(__2i));
    312   _Tp __2rsh(sinh(__2r));
    313   if (std::isinf(__2rsh) && std::isinf(__d))
    314     return std::complex<_Tp>(__2rsh > _Tp(0) ? _Tp(1) : _Tp(-1),
    315                              __2i > _Tp(0) ? _Tp(0) : _Tp(-0.));
    316   return std::complex<_Tp>(__2rsh / __d, sin(__2i) / __d);
    317 }
    318 
    319 // asin
    320 
    321 template <class _Tp>
    322 __DEVICE__ std::complex<_Tp> asin(const std::complex<_Tp> &__x) {
    323   std::complex<_Tp> __z = asinh(complex<_Tp>(-__x.imag(), __x.real()));
    324   return std::complex<_Tp>(__z.imag(), -__z.real());
    325 }
    326 
    327 // acos
    328 
    329 template <class _Tp>
    330 __DEVICE__ std::complex<_Tp> acos(const std::complex<_Tp> &__x) {
    331   const _Tp __pi(atan2(+0., -0.));
    332   if (std::isinf(__x.real())) {
    333     if (std::isnan(__x.imag()))
    334       return std::complex<_Tp>(__x.imag(), __x.real());
    335     if (std::isinf(__x.imag())) {
    336       if (__x.real() < _Tp(0))
    337         return std::complex<_Tp>(_Tp(0.75) * __pi, -__x.imag());
    338       return std::complex<_Tp>(_Tp(0.25) * __pi, -__x.imag());
    339     }
    340     if (__x.real() < _Tp(0))
    341       return std::complex<_Tp>(__pi,
    342                                signbit(__x.imag()) ? -__x.real() : __x.real());
    343     return std::complex<_Tp>(_Tp(0),
    344                              signbit(__x.imag()) ? __x.real() : -__x.real());
    345   }
    346   if (std::isnan(__x.real())) {
    347     if (std::isinf(__x.imag()))
    348       return std::complex<_Tp>(__x.real(), -__x.imag());
    349     return std::complex<_Tp>(__x.real(), __x.real());
    350   }
    351   if (std::isinf(__x.imag()))
    352     return std::complex<_Tp>(__pi / _Tp(2), -__x.imag());
    353   if (__x.real() == 0 && (__x.imag() == 0 || isnan(__x.imag())))
    354     return std::complex<_Tp>(__pi / _Tp(2), -__x.imag());
    355   std::complex<_Tp> __z = log(__x + sqrt(__sqr(__x) - _Tp(1)));
    356   if (signbit(__x.imag()))
    357     return std::complex<_Tp>(abs(__z.imag()), abs(__z.real()));
    358   return std::complex<_Tp>(abs(__z.imag()), -abs(__z.real()));
    359 }
    360 
    361 // atan
    362 
    363 template <class _Tp>
    364 __DEVICE__ std::complex<_Tp> atan(const std::complex<_Tp> &__x) {
    365   std::complex<_Tp> __z = atanh(complex<_Tp>(-__x.imag(), __x.real()));
    366   return std::complex<_Tp>(__z.imag(), -__z.real());
    367 }
    368 
    369 // sin
    370 
    371 template <class _Tp>
    372 __DEVICE__ std::complex<_Tp> sin(const std::complex<_Tp> &__x) {
    373   std::complex<_Tp> __z = sinh(complex<_Tp>(-__x.imag(), __x.real()));
    374   return std::complex<_Tp>(__z.imag(), -__z.real());
    375 }
    376 
    377 // cos
    378 
    379 template <class _Tp> std::complex<_Tp> cos(const std::complex<_Tp> &__x) {
    380   return cosh(complex<_Tp>(-__x.imag(), __x.real()));
    381 }
    382 
    383 // tan
    384 
    385 template <class _Tp>
    386 __DEVICE__ std::complex<_Tp> tan(const std::complex<_Tp> &__x) {
    387   std::complex<_Tp> __z = tanh(complex<_Tp>(-__x.imag(), __x.real()));
    388   return std::complex<_Tp>(__z.imag(), -__z.real());
    389 }
    390 
    391 } // namespace std
    392 
    393 #endif