1 // The template and inlines for the -*- C++ -*- internal _Meta class.
2
3 // Copyright (C) 1997-2021 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24
25 /** @file bits/valarray_before.h
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{valarray}
28 */
29
30 // Written by Gabriel Dos Reis <Gabriel.Dos-Reis@cmla.ens-cachan.fr>
31
32 #ifndef _VALARRAY_BEFORE_H
33 #define _VALARRAY_BEFORE_H 1
34
35 #pragma GCC system_header
36
37 #include <bits/slice_array.h>
38
_GLIBCXX_VISIBILITY(default)39 namespace std _GLIBCXX_VISIBILITY(default)
40 {
41 _GLIBCXX_BEGIN_NAMESPACE_VERSION
42
43 //
44 // Implementing a loosened valarray return value is tricky.
45 // First we need to meet 26.3.1/3: we should not add more than
46 // two levels of template nesting. Therefore we resort to template
47 // template to "flatten" loosened return value types.
48 // At some point we use partial specialization to remove one level
49 // template nesting due to _Expr<>
50 //
51
52 // This class is NOT defined. It doesn't need to.
53 template<typename _Tp1, typename _Tp2> class _Constant;
54
55 // Implementations of unary functions applied to valarray<>s.
56 // I use hard-coded object functions here instead of a generic
57 // approach like pointers to function:
58 // 1) correctness: some functions take references, others values.
59 // we can't deduce the correct type afterwards.
60 // 2) efficiency -- object functions can be easily inlined
61 // 3) be Koenig-lookup-friendly
62
63 struct _Abs
64 {
65 template<typename _Tp>
66 _Tp operator()(const _Tp& __t) const
67 { return abs(__t); }
68 };
69
70 struct _Cos
71 {
72 template<typename _Tp>
73 _Tp operator()(const _Tp& __t) const
74 { return cos(__t); }
75 };
76
77 struct _Acos
78 {
79 template<typename _Tp>
80 _Tp operator()(const _Tp& __t) const
81 { return acos(__t); }
82 };
83
84 struct _Cosh
85 {
86 template<typename _Tp>
87 _Tp operator()(const _Tp& __t) const
88 { return cosh(__t); }
89 };
90
91 struct _Sin
92 {
93 template<typename _Tp>
94 _Tp operator()(const _Tp& __t) const
95 { return sin(__t); }
96 };
97
98 struct _Asin
99 {
100 template<typename _Tp>
101 _Tp operator()(const _Tp& __t) const
102 { return asin(__t); }
103 };
104
105 struct _Sinh
106 {
107 template<typename _Tp>
108 _Tp operator()(const _Tp& __t) const
109 { return sinh(__t); }
110 };
111
112 struct _Tan
113 {
114 template<typename _Tp>
115 _Tp operator()(const _Tp& __t) const
116 { return tan(__t); }
117 };
118
119 struct _Atan
120 {
121 template<typename _Tp>
122 _Tp operator()(const _Tp& __t) const
123 { return atan(__t); }
124 };
125
126 struct _Tanh
127 {
128 template<typename _Tp>
129 _Tp operator()(const _Tp& __t) const
130 { return tanh(__t); }
131 };
132
133 struct _Exp
134 {
135 template<typename _Tp>
136 _Tp operator()(const _Tp& __t) const
137 { return exp(__t); }
138 };
139
140 struct _Log
141 {
142 template<typename _Tp>
143 _Tp operator()(const _Tp& __t) const
144 { return log(__t); }
145 };
146
147 struct _Log10
148 {
149 template<typename _Tp>
150 _Tp operator()(const _Tp& __t) const
151 { return log10(__t); }
152 };
153
154 struct _Sqrt
155 {
156 template<typename _Tp>
157 _Tp operator()(const _Tp& __t) const
158 { return sqrt(__t); }
159 };
160
161 // In the past, we used to tailor operator applications semantics
162 // to the specialization of standard function objects (i.e. plus<>, etc.)
163 // That is incorrect. Therefore we provide our own surrogates.
164
165 struct __unary_plus
166 {
167 template<typename _Tp>
168 _Tp operator()(const _Tp& __t) const
169 { return +__t; }
170 };
171
172 struct __negate
173 {
174 template<typename _Tp>
175 _Tp operator()(const _Tp& __t) const
176 { return -__t; }
177 };
178
179 struct __bitwise_not
180 {
181 template<typename _Tp>
182 _Tp operator()(const _Tp& __t) const
183 { return ~__t; }
184 };
185
186 struct __plus
187 {
188 template<typename _Tp>
189 _Tp operator()(const _Tp& __x, const _Tp& __y) const
190 { return __x + __y; }
191 };
192
193 struct __minus
194 {
195 template<typename _Tp>
196 _Tp operator()(const _Tp& __x, const _Tp& __y) const
197 { return __x - __y; }
198 };
199
200 struct __multiplies
201 {
202 template<typename _Tp>
203 _Tp operator()(const _Tp& __x, const _Tp& __y) const
204 { return __x * __y; }
205 };
206
207 struct __divides
208 {
209 template<typename _Tp>
210 _Tp operator()(const _Tp& __x, const _Tp& __y) const
211 { return __x / __y; }
212 };
213
214 struct __modulus
215 {
216 template<typename _Tp>
217 _Tp operator()(const _Tp& __x, const _Tp& __y) const
218 { return __x % __y; }
219 };
220
221 struct __bitwise_xor
222 {
223 template<typename _Tp>
224 _Tp operator()(const _Tp& __x, const _Tp& __y) const
225 { return __x ^ __y; }
226 };
227
228 struct __bitwise_and
229 {
230 template<typename _Tp>
231 _Tp operator()(const _Tp& __x, const _Tp& __y) const
232 { return __x & __y; }
233 };
234
235 struct __bitwise_or
236 {
237 template<typename _Tp>
238 _Tp operator()(const _Tp& __x, const _Tp& __y) const
239 { return __x | __y; }
240 };
241
242 struct __shift_left
243 {
244 template<typename _Tp>
245 _Tp operator()(const _Tp& __x, const _Tp& __y) const
246 { return __x << __y; }
247 };
248
249 struct __shift_right
250 {
251 template<typename _Tp>
252 _Tp operator()(const _Tp& __x, const _Tp& __y) const
253 { return __x >> __y; }
254 };
255
256 struct __logical_and
257 {
258 template<typename _Tp>
259 bool operator()(const _Tp& __x, const _Tp& __y) const
260 { return __x && __y; }
261 };
262
263 struct __logical_or
264 {
265 template<typename _Tp>
266 bool operator()(const _Tp& __x, const _Tp& __y) const
267 { return __x || __y; }
268 };
269
270 struct __logical_not
271 {
272 template<typename _Tp>
273 bool operator()(const _Tp& __x) const
274 { return !__x; }
275 };
276
277 struct __equal_to
278 {
279 template<typename _Tp>
280 bool operator()(const _Tp& __x, const _Tp& __y) const
281 { return __x == __y; }
282 };
283
284 struct __not_equal_to
285 {
286 template<typename _Tp>
287 bool operator()(const _Tp& __x, const _Tp& __y) const
288 { return __x != __y; }
289 };
290
291 struct __less
292 {
293 template<typename _Tp>
294 bool operator()(const _Tp& __x, const _Tp& __y) const
295 { return __x < __y; }
296 };
297
298 struct __greater
299 {
300 template<typename _Tp>
301 bool operator()(const _Tp& __x, const _Tp& __y) const
302 { return __x > __y; }
303 };
304
305 struct __less_equal
306 {
307 template<typename _Tp>
308 bool operator()(const _Tp& __x, const _Tp& __y) const
309 { return __x <= __y; }
310 };
311
312 struct __greater_equal
313 {
314 template<typename _Tp>
315 bool operator()(const _Tp& __x, const _Tp& __y) const
316 { return __x >= __y; }
317 };
318
319 // The few binary functions we miss.
320 struct _Atan2
321 {
322 template<typename _Tp>
323 _Tp operator()(const _Tp& __x, const _Tp& __y) const
324 { return atan2(__x, __y); }
325 };
326
327 struct _Pow
328 {
329 template<typename _Tp>
330 _Tp operator()(const _Tp& __x, const _Tp& __y) const
331 { return pow(__x, __y); }
332 };
333
334 template<typename _Tp, bool _IsValidValarrayValue = !__is_abstract(_Tp)>
335 struct __fun_with_valarray
336 {
337 typedef _Tp result_type;
338 };
339
340 template<typename _Tp>
341 struct __fun_with_valarray<_Tp, false>
342 {
343 // No result type defined for invalid value types.
344 };
345
346 // We need these bits in order to recover the return type of
347 // some functions/operators now that we're no longer using
348 // function templates.
349 template<typename, typename _Tp>
350 struct __fun : __fun_with_valarray<_Tp>
351 {
352 };
353
354 // several specializations for relational operators.
355 template<typename _Tp>
356 struct __fun<__logical_not, _Tp>
357 {
358 typedef bool result_type;
359 };
360
361 template<typename _Tp>
362 struct __fun<__logical_and, _Tp>
363 {
364 typedef bool result_type;
365 };
366
367 template<typename _Tp>
368 struct __fun<__logical_or, _Tp>
369 {
370 typedef bool result_type;
371 };
372
373 template<typename _Tp>
374 struct __fun<__less, _Tp>
375 {
376 typedef bool result_type;
377 };
378
379 template<typename _Tp>
380 struct __fun<__greater, _Tp>
381 {
382 typedef bool result_type;
383 };
384
385 template<typename _Tp>
386 struct __fun<__less_equal, _Tp>
387 {
388 typedef bool result_type;
389 };
390
391 template<typename _Tp>
392 struct __fun<__greater_equal, _Tp>
393 {
394 typedef bool result_type;
395 };
396
397 template<typename _Tp>
398 struct __fun<__equal_to, _Tp>
399 {
400 typedef bool result_type;
401 };
402
403 template<typename _Tp>
404 struct __fun<__not_equal_to, _Tp>
405 {
406 typedef bool result_type;
407 };
408
409 namespace __detail
410 {
411 // Closure types already have reference semantics and are often short-lived,
412 // so store them by value to avoid (some cases of) dangling references to
413 // out-of-scope temporaries.
414 template<typename _Tp>
415 struct _ValArrayRef
416 { typedef const _Tp __type; };
417
418 // Use real references for std::valarray objects.
419 template<typename _Tp>
420 struct _ValArrayRef< valarray<_Tp> >
421 { typedef const valarray<_Tp>& __type; };
422
423 //
424 // Apply function taking a value/const reference closure
425 //
426
427 template<typename _Dom, typename _Arg>
428 class _FunBase
429 {
430 public:
431 typedef typename _Dom::value_type value_type;
432
433 _FunBase(const _Dom& __e, value_type __f(_Arg))
434 : _M_expr(__e), _M_func(__f) {}
435
436 value_type operator[](size_t __i) const
437 { return _M_func (_M_expr[__i]); }
438
439 size_t size() const { return _M_expr.size ();}
440
441 private:
442 typename _ValArrayRef<_Dom>::__type _M_expr;
443 value_type (*_M_func)(_Arg);
444 };
445
446 template<class _Dom>
447 struct _ValFunClos<_Expr,_Dom> : _FunBase<_Dom, typename _Dom::value_type>
448 {
449 typedef _FunBase<_Dom, typename _Dom::value_type> _Base;
450 typedef typename _Base::value_type value_type;
451 typedef value_type _Tp;
452
453 _ValFunClos(const _Dom& __e, _Tp __f(_Tp)) : _Base(__e, __f) {}
454 };
455
456 template<typename _Tp>
457 struct _ValFunClos<_ValArray,_Tp> : _FunBase<valarray<_Tp>, _Tp>
458 {
459 typedef _FunBase<valarray<_Tp>, _Tp> _Base;
460 typedef _Tp value_type;
461
462 _ValFunClos(const valarray<_Tp>& __v, _Tp __f(_Tp)) : _Base(__v, __f) {}
463 };
464
465 template<class _Dom>
466 struct _RefFunClos<_Expr, _Dom>
467 : _FunBase<_Dom, const typename _Dom::value_type&>
468 {
469 typedef _FunBase<_Dom, const typename _Dom::value_type&> _Base;
470 typedef typename _Base::value_type value_type;
471 typedef value_type _Tp;
472
473 _RefFunClos(const _Dom& __e, _Tp __f(const _Tp&))
474 : _Base(__e, __f) {}
475 };
476
477 template<typename _Tp>
478 struct _RefFunClos<_ValArray, _Tp>
479 : _FunBase<valarray<_Tp>, const _Tp&>
480 {
481 typedef _FunBase<valarray<_Tp>, const _Tp&> _Base;
482 typedef _Tp value_type;
483
484 _RefFunClos(const valarray<_Tp>& __v, _Tp __f(const _Tp&))
485 : _Base(__v, __f) {}
486 };
487
488 //
489 // Unary expression closure.
490 //
491
492 template<class _Oper, class _Arg>
493 class _UnBase
494 {
495 public:
496 typedef typename _Arg::value_type _Vt;
497 typedef typename __fun<_Oper, _Vt>::result_type value_type;
498
499 _UnBase(const _Arg& __e) : _M_expr(__e) {}
500
501 value_type operator[](size_t __i) const
502 { return _Oper()(_M_expr[__i]); }
503
504 size_t size() const { return _M_expr.size(); }
505
506 private:
507 typename _ValArrayRef<_Arg>::__type _M_expr;
508 };
509
510 template<class _Oper, class _Dom>
511 struct _UnClos<_Oper, _Expr, _Dom>
512 : _UnBase<_Oper, _Dom>
513 {
514 typedef _Dom _Arg;
515 typedef _UnBase<_Oper, _Dom> _Base;
516 typedef typename _Base::value_type value_type;
517
518 _UnClos(const _Arg& __e) : _Base(__e) {}
519 };
520
521 template<class _Oper, typename _Tp>
522 struct _UnClos<_Oper, _ValArray, _Tp>
523 : _UnBase<_Oper, valarray<_Tp> >
524 {
525 typedef valarray<_Tp> _Arg;
526 typedef _UnBase<_Oper, valarray<_Tp> > _Base;
527 typedef typename _Base::value_type value_type;
528
529 _UnClos(const _Arg& __e) : _Base(__e) {}
530 };
531
532
533 //
534 // Binary expression closure.
535 //
536
537 template<class _Oper, class _FirstArg, class _SecondArg>
538 class _BinBase
539 {
540 public:
541 typedef typename _FirstArg::value_type _Vt;
542 typedef typename __fun<_Oper, _Vt>::result_type value_type;
543
544 _BinBase(const _FirstArg& __e1, const _SecondArg& __e2)
545 : _M_expr1(__e1), _M_expr2(__e2) {}
546
547 value_type operator[](size_t __i) const
548 { return _Oper()(_M_expr1[__i], _M_expr2[__i]); }
549
550 size_t size() const { return _M_expr1.size(); }
551
552 private:
553 typename _ValArrayRef<_FirstArg>::__type _M_expr1;
554 typename _ValArrayRef<_SecondArg>::__type _M_expr2;
555 };
556
557
558 template<class _Oper, class _Clos>
559 class _BinBase2
560 {
561 public:
562 typedef typename _Clos::value_type _Vt;
563 typedef typename __fun<_Oper, _Vt>::result_type value_type;
564
565 _BinBase2(const _Clos& __e, const _Vt& __t)
566 : _M_expr1(__e), _M_expr2(__t) {}
567
568 value_type operator[](size_t __i) const
569 { return _Oper()(_M_expr1[__i], _M_expr2); }
570
571 size_t size() const { return _M_expr1.size(); }
572
573 private:
574 typename _ValArrayRef<_Clos>::__type _M_expr1;
575 _Vt _M_expr2;
576 };
577
578 template<class _Oper, class _Clos>
579 class _BinBase1
580 {
581 public:
582 typedef typename _Clos::value_type _Vt;
583 typedef typename __fun<_Oper, _Vt>::result_type value_type;
584
585 _BinBase1(const _Vt& __t, const _Clos& __e)
586 : _M_expr1(__t), _M_expr2(__e) {}
587
588 value_type operator[](size_t __i) const
589 { return _Oper()(_M_expr1, _M_expr2[__i]); }
590
591 size_t size() const { return _M_expr2.size(); }
592
593 private:
594 _Vt _M_expr1;
595 typename _ValArrayRef<_Clos>::__type _M_expr2;
596 };
597
598 template<class _Oper, class _Dom1, class _Dom2>
599 struct _BinClos<_Oper, _Expr, _Expr, _Dom1, _Dom2>
600 : _BinBase<_Oper, _Dom1, _Dom2>
601 {
602 typedef _BinBase<_Oper, _Dom1, _Dom2> _Base;
603 typedef typename _Base::value_type value_type;
604
605 _BinClos(const _Dom1& __e1, const _Dom2& __e2) : _Base(__e1, __e2) {}
606 };
607
608 template<class _Oper, typename _Tp>
609 struct _BinClos<_Oper, _ValArray, _ValArray, _Tp, _Tp>
610 : _BinBase<_Oper, valarray<_Tp>, valarray<_Tp> >
611 {
612 typedef _BinBase<_Oper, valarray<_Tp>, valarray<_Tp> > _Base;
613 typedef typename _Base::value_type value_type;
614
615 _BinClos(const valarray<_Tp>& __v, const valarray<_Tp>& __w)
616 : _Base(__v, __w) {}
617 };
618
619 template<class _Oper, class _Dom>
620 struct _BinClos<_Oper, _Expr, _ValArray, _Dom, typename _Dom::value_type>
621 : _BinBase<_Oper, _Dom, valarray<typename _Dom::value_type> >
622 {
623 typedef typename _Dom::value_type _Tp;
624 typedef _BinBase<_Oper,_Dom,valarray<_Tp> > _Base;
625 typedef typename _Base::value_type value_type;
626
627 _BinClos(const _Dom& __e1, const valarray<_Tp>& __e2)
628 : _Base(__e1, __e2) {}
629 };
630
631 template<class _Oper, class _Dom>
632 struct _BinClos<_Oper, _ValArray, _Expr, typename _Dom::value_type, _Dom>
633 : _BinBase<_Oper, valarray<typename _Dom::value_type>,_Dom>
634 {
635 typedef typename _Dom::value_type _Tp;
636 typedef _BinBase<_Oper, valarray<_Tp>, _Dom> _Base;
637 typedef typename _Base::value_type value_type;
638
639 _BinClos(const valarray<_Tp>& __e1, const _Dom& __e2)
640 : _Base(__e1, __e2) {}
641 };
642
643 template<class _Oper, class _Dom>
644 struct _BinClos<_Oper, _Expr, _Constant, _Dom, typename _Dom::value_type>
645 : _BinBase2<_Oper, _Dom>
646 {
647 typedef typename _Dom::value_type _Tp;
648 typedef _BinBase2<_Oper,_Dom> _Base;
649 typedef typename _Base::value_type value_type;
650
651 _BinClos(const _Dom& __e1, const _Tp& __e2) : _Base(__e1, __e2) {}
652 };
653
654 template<class _Oper, class _Dom>
655 struct _BinClos<_Oper, _Constant, _Expr, typename _Dom::value_type, _Dom>
656 : _BinBase1<_Oper, _Dom>
657 {
658 typedef typename _Dom::value_type _Tp;
659 typedef _BinBase1<_Oper, _Dom> _Base;
660 typedef typename _Base::value_type value_type;
661
662 _BinClos(const _Tp& __e1, const _Dom& __e2) : _Base(__e1, __e2) {}
663 };
664
665 template<class _Oper, typename _Tp>
666 struct _BinClos<_Oper, _ValArray, _Constant, _Tp, _Tp>
667 : _BinBase2<_Oper, valarray<_Tp> >
668 {
669 typedef _BinBase2<_Oper,valarray<_Tp> > _Base;
670 typedef typename _Base::value_type value_type;
671
672 _BinClos(const valarray<_Tp>& __v, const _Tp& __t) : _Base(__v, __t) {}
673 };
674
675 template<class _Oper, typename _Tp>
676 struct _BinClos<_Oper, _Constant, _ValArray, _Tp, _Tp>
677 : _BinBase1<_Oper, valarray<_Tp> >
678 {
679 typedef _BinBase1<_Oper, valarray<_Tp> > _Base;
680 typedef typename _Base::value_type value_type;
681
682 _BinClos(const _Tp& __t, const valarray<_Tp>& __v) : _Base(__t, __v) {}
683 };
684
685 //
686 // slice_array closure.
687 //
688 template<typename _Dom>
689 class _SBase
690 {
691 public:
692 typedef typename _Dom::value_type value_type;
693
694 _SBase (const _Dom& __e, const slice& __s)
695 : _M_expr (__e), _M_slice (__s) {}
696
697 value_type
698 operator[] (size_t __i) const
699 { return _M_expr[_M_slice.start () + __i * _M_slice.stride ()]; }
700
701 size_t
702 size() const
703 { return _M_slice.size (); }
704
705 private:
706 typename _ValArrayRef<_Dom>::__type _M_expr;
707 const slice& _M_slice;
708 };
709
710 template<typename _Tp>
711 class _SBase<_Array<_Tp> >
712 {
713 public:
714 typedef _Tp value_type;
715
716 _SBase (_Array<_Tp> __a, const slice& __s)
717 : _M_array (__a._M_data+__s.start()), _M_size (__s.size()),
718 _M_stride (__s.stride()) {}
719
720 value_type
721 operator[] (size_t __i) const
722 { return _M_array._M_data[__i * _M_stride]; }
723
724 size_t
725 size() const
726 { return _M_size; }
727
728 private:
729 const _Array<_Tp> _M_array;
730 const size_t _M_size;
731 const size_t _M_stride;
732 };
733
734 template<class _Dom>
735 struct _SClos<_Expr, _Dom>
736 : _SBase<_Dom>
737 {
738 typedef _SBase<_Dom> _Base;
739 typedef typename _Base::value_type value_type;
740
741 _SClos (const _Dom& __e, const slice& __s) : _Base (__e, __s) {}
742 };
743
744 template<typename _Tp>
745 struct _SClos<_ValArray, _Tp>
746 : _SBase<_Array<_Tp> >
747 {
748 typedef _SBase<_Array<_Tp> > _Base;
749 typedef _Tp value_type;
750
751 _SClos (_Array<_Tp> __a, const slice& __s) : _Base (__a, __s) {}
752 };
753 } // namespace __detail
754
755 _GLIBCXX_END_NAMESPACE_VERSION
756 } // namespace
757
758 #endif /* _CPP_VALARRAY_BEFORE_H */
759