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[official-gcc.git] / libgfortran / intrinsics / c99_functions.c
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1 /* Implementation of various C99 functions
2 Copyright (C) 2004-2016 Free Software Foundation, Inc.
4 This file is part of the GNU Fortran 95 runtime library (libgfortran).
6 Libgfortran is free software; you can redistribute it and/or
7 modify it under the terms of the GNU General Public
8 License as published by the Free Software Foundation; either
9 version 3 of the License, or (at your option) any later version.
11 Libgfortran 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.
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.
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/>. */
25 #include "config.h"
27 #define C99_PROTOS_H WE_DONT_WANT_PROTOS_NOW
28 #include "libgfortran.h"
30 /* On a C99 system "I" (with I*I = -1) should be defined in complex.h;
31 if not, we define a fallback version here. */
32 #ifndef I
33 # if defined(_Imaginary_I)
34 # define I _Imaginary_I
35 # elif defined(_Complex_I)
36 # define I _Complex_I
37 # else
38 # define I (1.0fi)
39 # endif
40 #endif
42 /* Macros to get real and imaginary parts of a complex, and set
43 a complex value. */
44 #define REALPART(z) (__real__(z))
45 #define IMAGPART(z) (__imag__(z))
46 #define COMPLEX_ASSIGN(z_, r_, i_) {__real__(z_) = (r_); __imag__(z_) = (i_);}
49 /* Prototypes are included to silence -Wstrict-prototypes
50 -Wmissing-prototypes. */
53 /* Wrappers for systems without the various C99 single precision Bessel
54 functions. */
56 #if defined(HAVE_J0) && ! defined(HAVE_J0F)
57 #define HAVE_J0F 1
58 float j0f (float);
60 float
61 j0f (float x)
63 return (float) j0 ((double) x);
65 #endif
67 #if defined(HAVE_J1) && !defined(HAVE_J1F)
68 #define HAVE_J1F 1
69 float j1f (float);
71 float j1f (float x)
73 return (float) j1 ((double) x);
75 #endif
77 #if defined(HAVE_JN) && !defined(HAVE_JNF)
78 #define HAVE_JNF 1
79 float jnf (int, float);
81 float
82 jnf (int n, float x)
84 return (float) jn (n, (double) x);
86 #endif
88 #if defined(HAVE_Y0) && !defined(HAVE_Y0F)
89 #define HAVE_Y0F 1
90 float y0f (float);
92 float
93 y0f (float x)
95 return (float) y0 ((double) x);
97 #endif
99 #if defined(HAVE_Y1) && !defined(HAVE_Y1F)
100 #define HAVE_Y1F 1
101 float y1f (float);
103 float
104 y1f (float x)
106 return (float) y1 ((double) x);
108 #endif
110 #if defined(HAVE_YN) && !defined(HAVE_YNF)
111 #define HAVE_YNF 1
112 float ynf (int, float);
114 float
115 ynf (int n, float x)
117 return (float) yn (n, (double) x);
119 #endif
122 /* Wrappers for systems without the C99 erff() and erfcf() functions. */
124 #if defined(HAVE_ERF) && !defined(HAVE_ERFF)
125 #define HAVE_ERFF 1
126 float erff (float);
128 float
129 erff (float x)
131 return (float) erf ((double) x);
133 #endif
135 #if defined(HAVE_ERFC) && !defined(HAVE_ERFCF)
136 #define HAVE_ERFCF 1
137 float erfcf (float);
139 float
140 erfcf (float x)
142 return (float) erfc ((double) x);
144 #endif
147 #ifndef HAVE_ACOSF
148 #define HAVE_ACOSF 1
149 float acosf (float x);
151 float
152 acosf (float x)
154 return (float) acos (x);
156 #endif
158 #if HAVE_ACOSH && !HAVE_ACOSHF
159 float acoshf (float x);
161 float
162 acoshf (float x)
164 return (float) acosh ((double) x);
166 #endif
168 #ifndef HAVE_ASINF
169 #define HAVE_ASINF 1
170 float asinf (float x);
172 float
173 asinf (float x)
175 return (float) asin (x);
177 #endif
179 #if HAVE_ASINH && !HAVE_ASINHF
180 float asinhf (float x);
182 float
183 asinhf (float x)
185 return (float) asinh ((double) x);
187 #endif
189 #ifndef HAVE_ATAN2F
190 #define HAVE_ATAN2F 1
191 float atan2f (float y, float x);
193 float
194 atan2f (float y, float x)
196 return (float) atan2 (y, x);
198 #endif
200 #ifndef HAVE_ATANF
201 #define HAVE_ATANF 1
202 float atanf (float x);
204 float
205 atanf (float x)
207 return (float) atan (x);
209 #endif
211 #if HAVE_ATANH && !HAVE_ATANHF
212 float atanhf (float x);
214 float
215 atanhf (float x)
217 return (float) atanh ((double) x);
219 #endif
221 #ifndef HAVE_CEILF
222 #define HAVE_CEILF 1
223 float ceilf (float x);
225 float
226 ceilf (float x)
228 return (float) ceil (x);
230 #endif
232 #ifndef HAVE_COPYSIGNF
233 #define HAVE_COPYSIGNF 1
234 float copysignf (float x, float y);
236 float
237 copysignf (float x, float y)
239 return (float) copysign (x, y);
241 #endif
243 #ifndef HAVE_COSF
244 #define HAVE_COSF 1
245 float cosf (float x);
247 float
248 cosf (float x)
250 return (float) cos (x);
252 #endif
254 #ifndef HAVE_COSHF
255 #define HAVE_COSHF 1
256 float coshf (float x);
258 float
259 coshf (float x)
261 return (float) cosh (x);
263 #endif
265 #ifndef HAVE_EXPF
266 #define HAVE_EXPF 1
267 float expf (float x);
269 float
270 expf (float x)
272 return (float) exp (x);
274 #endif
276 #ifndef HAVE_FABSF
277 #define HAVE_FABSF 1
278 float fabsf (float x);
280 float
281 fabsf (float x)
283 return (float) fabs (x);
285 #endif
287 #ifndef HAVE_FLOORF
288 #define HAVE_FLOORF 1
289 float floorf (float x);
291 float
292 floorf (float x)
294 return (float) floor (x);
296 #endif
298 #ifndef HAVE_FMODF
299 #define HAVE_FMODF 1
300 float fmodf (float x, float y);
302 float
303 fmodf (float x, float y)
305 return (float) fmod (x, y);
307 #endif
309 #ifndef HAVE_FREXPF
310 #define HAVE_FREXPF 1
311 float frexpf (float x, int *exp);
313 float
314 frexpf (float x, int *exp)
316 return (float) frexp (x, exp);
318 #endif
320 #ifndef HAVE_HYPOTF
321 #define HAVE_HYPOTF 1
322 float hypotf (float x, float y);
324 float
325 hypotf (float x, float y)
327 return (float) hypot (x, y);
329 #endif
331 #ifndef HAVE_LOGF
332 #define HAVE_LOGF 1
333 float logf (float x);
335 float
336 logf (float x)
338 return (float) log (x);
340 #endif
342 #ifndef HAVE_LOG10F
343 #define HAVE_LOG10F 1
344 float log10f (float x);
346 float
347 log10f (float x)
349 return (float) log10 (x);
351 #endif
353 #ifndef HAVE_SCALBN
354 #define HAVE_SCALBN 1
355 double scalbn (double x, int y);
357 double
358 scalbn (double x, int y)
360 #if (FLT_RADIX == 2) && defined(HAVE_LDEXP)
361 return ldexp (x, y);
362 #else
363 return x * pow (FLT_RADIX, y);
364 #endif
366 #endif
368 #ifndef HAVE_SCALBNF
369 #define HAVE_SCALBNF 1
370 float scalbnf (float x, int y);
372 float
373 scalbnf (float x, int y)
375 return (float) scalbn (x, y);
377 #endif
379 #ifndef HAVE_SINF
380 #define HAVE_SINF 1
381 float sinf (float x);
383 float
384 sinf (float x)
386 return (float) sin (x);
388 #endif
390 #ifndef HAVE_SINHF
391 #define HAVE_SINHF 1
392 float sinhf (float x);
394 float
395 sinhf (float x)
397 return (float) sinh (x);
399 #endif
401 #ifndef HAVE_SQRTF
402 #define HAVE_SQRTF 1
403 float sqrtf (float x);
405 float
406 sqrtf (float x)
408 return (float) sqrt (x);
410 #endif
412 #ifndef HAVE_TANF
413 #define HAVE_TANF 1
414 float tanf (float x);
416 float
417 tanf (float x)
419 return (float) tan (x);
421 #endif
423 #ifndef HAVE_TANHF
424 #define HAVE_TANHF 1
425 float tanhf (float x);
427 float
428 tanhf (float x)
430 return (float) tanh (x);
432 #endif
434 #ifndef HAVE_TRUNC
435 #define HAVE_TRUNC 1
436 double trunc (double x);
438 double
439 trunc (double x)
441 if (!isfinite (x))
442 return x;
444 if (x < 0.0)
445 return - floor (-x);
446 else
447 return floor (x);
449 #endif
451 #ifndef HAVE_TRUNCF
452 #define HAVE_TRUNCF 1
453 float truncf (float x);
455 float
456 truncf (float x)
458 return (float) trunc (x);
460 #endif
462 #ifndef HAVE_NEXTAFTERF
463 #define HAVE_NEXTAFTERF 1
464 /* This is a portable implementation of nextafterf that is intended to be
465 independent of the floating point format or its in memory representation.
466 This implementation works correctly with denormalized values. */
467 float nextafterf (float x, float y);
469 float
470 nextafterf (float x, float y)
472 /* This variable is marked volatile to avoid excess precision problems
473 on some platforms, including IA-32. */
474 volatile float delta;
475 float absx, denorm_min;
477 if (isnan (x) || isnan (y))
478 return x + y;
479 if (x == y)
480 return x;
481 if (!isfinite (x))
482 return x > 0 ? __FLT_MAX__ : - __FLT_MAX__;
484 /* absx = fabsf (x); */
485 absx = (x < 0.0) ? -x : x;
487 /* __FLT_DENORM_MIN__ is non-zero iff the target supports denormals. */
488 if (__FLT_DENORM_MIN__ == 0.0f)
489 denorm_min = __FLT_MIN__;
490 else
491 denorm_min = __FLT_DENORM_MIN__;
493 if (absx < __FLT_MIN__)
494 delta = denorm_min;
495 else
497 float frac;
498 int exp;
500 /* Discard the fraction from x. */
501 frac = frexpf (absx, &exp);
502 delta = scalbnf (0.5f, exp);
504 /* Scale x by the epsilon of the representation. By rights we should
505 have been able to combine this with scalbnf, but some targets don't
506 get that correct with denormals. */
507 delta *= __FLT_EPSILON__;
509 /* If we're going to be reducing the absolute value of X, and doing so
510 would reduce the exponent of X, then the delta to be applied is
511 one exponent smaller. */
512 if (frac == 0.5f && (y < x) == (x > 0))
513 delta *= 0.5f;
515 /* If that underflows to zero, then we're back to the minimum. */
516 if (delta == 0.0f)
517 delta = denorm_min;
520 if (y < x)
521 delta = -delta;
523 return x + delta;
525 #endif
528 #ifndef HAVE_POWF
529 #define HAVE_POWF 1
530 float powf (float x, float y);
532 float
533 powf (float x, float y)
535 return (float) pow (x, y);
537 #endif
540 #ifndef HAVE_ROUND
541 #define HAVE_ROUND 1
542 /* Round to nearest integral value. If the argument is halfway between two
543 integral values then round away from zero. */
544 double round (double x);
546 double
547 round (double x)
549 double t;
550 if (!isfinite (x))
551 return (x);
553 if (x >= 0.0)
555 t = floor (x);
556 if (t - x <= -0.5)
557 t += 1.0;
558 return (t);
560 else
562 t = floor (-x);
563 if (t + x <= -0.5)
564 t += 1.0;
565 return (-t);
568 #endif
571 /* Algorithm by Steven G. Kargl. */
573 #if !defined(HAVE_ROUNDL)
574 #define HAVE_ROUNDL 1
575 long double roundl (long double x);
577 #if defined(HAVE_CEILL)
578 /* Round to nearest integral value. If the argument is halfway between two
579 integral values then round away from zero. */
581 long double
582 roundl (long double x)
584 long double t;
585 if (!isfinite (x))
586 return (x);
588 if (x >= 0.0)
590 t = ceill (x);
591 if (t - x > 0.5)
592 t -= 1.0;
593 return (t);
595 else
597 t = ceill (-x);
598 if (t + x > 0.5)
599 t -= 1.0;
600 return (-t);
603 #else
605 /* Poor version of roundl for system that don't have ceill. */
606 long double
607 roundl (long double x)
609 if (x > DBL_MAX || x < -DBL_MAX)
611 #ifdef HAVE_NEXTAFTERL
612 long double prechalf = nextafterl (0.5L, LDBL_MAX);
613 #else
614 static long double prechalf = 0.5L;
615 #endif
616 return (GFC_INTEGER_LARGEST) (x + (x > 0 ? prechalf : -prechalf));
618 else
619 /* Use round(). */
620 return round ((double) x);
623 #endif
624 #endif
626 #ifndef HAVE_ROUNDF
627 #define HAVE_ROUNDF 1
628 /* Round to nearest integral value. If the argument is halfway between two
629 integral values then round away from zero. */
630 float roundf (float x);
632 float
633 roundf (float x)
635 float t;
636 if (!isfinite (x))
637 return (x);
639 if (x >= 0.0)
641 t = floorf (x);
642 if (t - x <= -0.5)
643 t += 1.0;
644 return (t);
646 else
648 t = floorf (-x);
649 if (t + x <= -0.5)
650 t += 1.0;
651 return (-t);
654 #endif
657 /* lround{f,,l} and llround{f,,l} functions. */
659 #if !defined(HAVE_LROUNDF) && defined(HAVE_ROUNDF)
660 #define HAVE_LROUNDF 1
661 long int lroundf (float x);
663 long int
664 lroundf (float x)
666 return (long int) roundf (x);
668 #endif
670 #if !defined(HAVE_LROUND) && defined(HAVE_ROUND)
671 #define HAVE_LROUND 1
672 long int lround (double x);
674 long int
675 lround (double x)
677 return (long int) round (x);
679 #endif
681 #if !defined(HAVE_LROUNDL) && defined(HAVE_ROUNDL)
682 #define HAVE_LROUNDL 1
683 long int lroundl (long double x);
685 long int
686 lroundl (long double x)
688 return (long long int) roundl (x);
690 #endif
692 #if !defined(HAVE_LLROUNDF) && defined(HAVE_ROUNDF)
693 #define HAVE_LLROUNDF 1
694 long long int llroundf (float x);
696 long long int
697 llroundf (float x)
699 return (long long int) roundf (x);
701 #endif
703 #if !defined(HAVE_LLROUND) && defined(HAVE_ROUND)
704 #define HAVE_LLROUND 1
705 long long int llround (double x);
707 long long int
708 llround (double x)
710 return (long long int) round (x);
712 #endif
714 #if !defined(HAVE_LLROUNDL) && defined(HAVE_ROUNDL)
715 #define HAVE_LLROUNDL 1
716 long long int llroundl (long double x);
718 long long int
719 llroundl (long double x)
721 return (long long int) roundl (x);
723 #endif
726 #ifndef HAVE_LOG10L
727 #define HAVE_LOG10L 1
728 /* log10 function for long double variables. The version provided here
729 reduces the argument until it fits into a double, then use log10. */
730 long double log10l (long double x);
732 long double
733 log10l (long double x)
735 #if LDBL_MAX_EXP > DBL_MAX_EXP
736 if (x > DBL_MAX)
738 double val;
739 int p2_result = 0;
740 if (x > 0x1p16383L) { p2_result += 16383; x /= 0x1p16383L; }
741 if (x > 0x1p8191L) { p2_result += 8191; x /= 0x1p8191L; }
742 if (x > 0x1p4095L) { p2_result += 4095; x /= 0x1p4095L; }
743 if (x > 0x1p2047L) { p2_result += 2047; x /= 0x1p2047L; }
744 if (x > 0x1p1023L) { p2_result += 1023; x /= 0x1p1023L; }
745 val = log10 ((double) x);
746 return (val + p2_result * .30102999566398119521373889472449302L);
748 #endif
749 #if LDBL_MIN_EXP < DBL_MIN_EXP
750 if (x < DBL_MIN)
752 double val;
753 int p2_result = 0;
754 if (x < 0x1p-16380L) { p2_result += 16380; x /= 0x1p-16380L; }
755 if (x < 0x1p-8189L) { p2_result += 8189; x /= 0x1p-8189L; }
756 if (x < 0x1p-4093L) { p2_result += 4093; x /= 0x1p-4093L; }
757 if (x < 0x1p-2045L) { p2_result += 2045; x /= 0x1p-2045L; }
758 if (x < 0x1p-1021L) { p2_result += 1021; x /= 0x1p-1021L; }
759 val = fabs (log10 ((double) x));
760 return (- val - p2_result * .30102999566398119521373889472449302L);
762 #endif
763 return log10 (x);
765 #endif
768 #ifndef HAVE_FLOORL
769 #define HAVE_FLOORL 1
770 long double floorl (long double x);
772 long double
773 floorl (long double x)
775 /* Zero, possibly signed. */
776 if (x == 0)
777 return x;
779 /* Large magnitude. */
780 if (x > DBL_MAX || x < (-DBL_MAX))
781 return x;
783 /* Small positive values. */
784 if (x >= 0 && x < DBL_MIN)
785 return 0;
787 /* Small negative values. */
788 if (x < 0 && x > (-DBL_MIN))
789 return -1;
791 return floor (x);
793 #endif
796 #ifndef HAVE_FMODL
797 #define HAVE_FMODL 1
798 long double fmodl (long double x, long double y);
800 long double
801 fmodl (long double x, long double y)
803 if (y == 0.0L)
804 return 0.0L;
806 /* Need to check that the result has the same sign as x and magnitude
807 less than the magnitude of y. */
808 return x - floorl (x / y) * y;
810 #endif
813 #if !defined(HAVE_CABSF)
814 #define HAVE_CABSF 1
815 float cabsf (float complex z);
817 float
818 cabsf (float complex z)
820 return hypotf (REALPART (z), IMAGPART (z));
822 #endif
824 #if !defined(HAVE_CABS)
825 #define HAVE_CABS 1
826 double cabs (double complex z);
828 double
829 cabs (double complex z)
831 return hypot (REALPART (z), IMAGPART (z));
833 #endif
835 #if !defined(HAVE_CABSL) && defined(HAVE_HYPOTL)
836 #define HAVE_CABSL 1
837 long double cabsl (long double complex z);
839 long double
840 cabsl (long double complex z)
842 return hypotl (REALPART (z), IMAGPART (z));
844 #endif
847 #if !defined(HAVE_CARGF)
848 #define HAVE_CARGF 1
849 float cargf (float complex z);
851 float
852 cargf (float complex z)
854 return atan2f (IMAGPART (z), REALPART (z));
856 #endif
858 #if !defined(HAVE_CARG)
859 #define HAVE_CARG 1
860 double carg (double complex z);
862 double
863 carg (double complex z)
865 return atan2 (IMAGPART (z), REALPART (z));
867 #endif
869 #if !defined(HAVE_CARGL) && defined(HAVE_ATAN2L)
870 #define HAVE_CARGL 1
871 long double cargl (long double complex z);
873 long double
874 cargl (long double complex z)
876 return atan2l (IMAGPART (z), REALPART (z));
878 #endif
881 /* exp(z) = exp(a)*(cos(b) + i sin(b)) */
882 #if !defined(HAVE_CEXPF)
883 #define HAVE_CEXPF 1
884 float complex cexpf (float complex z);
886 float complex
887 cexpf (float complex z)
889 float a, b;
890 float complex v;
892 a = REALPART (z);
893 b = IMAGPART (z);
894 COMPLEX_ASSIGN (v, cosf (b), sinf (b));
895 return expf (a) * v;
897 #endif
899 #if !defined(HAVE_CEXP)
900 #define HAVE_CEXP 1
901 double complex cexp (double complex z);
903 double complex
904 cexp (double complex z)
906 double a, b;
907 double complex v;
909 a = REALPART (z);
910 b = IMAGPART (z);
911 COMPLEX_ASSIGN (v, cos (b), sin (b));
912 return exp (a) * v;
914 #endif
916 #if !defined(HAVE_CEXPL) && defined(HAVE_COSL) && defined(HAVE_SINL) && defined(EXPL)
917 #define HAVE_CEXPL 1
918 long double complex cexpl (long double complex z);
920 long double complex
921 cexpl (long double complex z)
923 long double a, b;
924 long double complex v;
926 a = REALPART (z);
927 b = IMAGPART (z);
928 COMPLEX_ASSIGN (v, cosl (b), sinl (b));
929 return expl (a) * v;
931 #endif
934 /* log(z) = log (cabs(z)) + i*carg(z) */
935 #if !defined(HAVE_CLOGF)
936 #define HAVE_CLOGF 1
937 float complex clogf (float complex z);
939 float complex
940 clogf (float complex z)
942 float complex v;
944 COMPLEX_ASSIGN (v, logf (cabsf (z)), cargf (z));
945 return v;
947 #endif
949 #if !defined(HAVE_CLOG)
950 #define HAVE_CLOG 1
951 double complex clog (double complex z);
953 double complex
954 clog (double complex z)
956 double complex v;
958 COMPLEX_ASSIGN (v, log (cabs (z)), carg (z));
959 return v;
961 #endif
963 #if !defined(HAVE_CLOGL) && defined(HAVE_LOGL) && defined(HAVE_CABSL) && defined(HAVE_CARGL)
964 #define HAVE_CLOGL 1
965 long double complex clogl (long double complex z);
967 long double complex
968 clogl (long double complex z)
970 long double complex v;
972 COMPLEX_ASSIGN (v, logl (cabsl (z)), cargl (z));
973 return v;
975 #endif
978 /* log10(z) = log10 (cabs(z)) + i*carg(z) */
979 #if !defined(HAVE_CLOG10F)
980 #define HAVE_CLOG10F 1
981 float complex clog10f (float complex z);
983 float complex
984 clog10f (float complex z)
986 float complex v;
988 COMPLEX_ASSIGN (v, log10f (cabsf (z)), cargf (z));
989 return v;
991 #endif
993 #if !defined(HAVE_CLOG10)
994 #define HAVE_CLOG10 1
995 double complex clog10 (double complex z);
997 double complex
998 clog10 (double complex z)
1000 double complex v;
1002 COMPLEX_ASSIGN (v, log10 (cabs (z)), carg (z));
1003 return v;
1005 #endif
1007 #if !defined(HAVE_CLOG10L) && defined(HAVE_LOG10L) && defined(HAVE_CABSL) && defined(HAVE_CARGL)
1008 #define HAVE_CLOG10L 1
1009 long double complex clog10l (long double complex z);
1011 long double complex
1012 clog10l (long double complex z)
1014 long double complex v;
1016 COMPLEX_ASSIGN (v, log10l (cabsl (z)), cargl (z));
1017 return v;
1019 #endif
1022 /* pow(base, power) = cexp (power * clog (base)) */
1023 #if !defined(HAVE_CPOWF)
1024 #define HAVE_CPOWF 1
1025 float complex cpowf (float complex base, float complex power);
1027 float complex
1028 cpowf (float complex base, float complex power)
1030 return cexpf (power * clogf (base));
1032 #endif
1034 #if !defined(HAVE_CPOW)
1035 #define HAVE_CPOW 1
1036 double complex cpow (double complex base, double complex power);
1038 double complex
1039 cpow (double complex base, double complex power)
1041 return cexp (power * clog (base));
1043 #endif
1045 #if !defined(HAVE_CPOWL) && defined(HAVE_CEXPL) && defined(HAVE_CLOGL)
1046 #define HAVE_CPOWL 1
1047 long double complex cpowl (long double complex base, long double complex power);
1049 long double complex
1050 cpowl (long double complex base, long double complex power)
1052 return cexpl (power * clogl (base));
1054 #endif
1057 /* sqrt(z). Algorithm pulled from glibc. */
1058 #if !defined(HAVE_CSQRTF)
1059 #define HAVE_CSQRTF 1
1060 float complex csqrtf (float complex z);
1062 float complex
1063 csqrtf (float complex z)
1065 float re, im;
1066 float complex v;
1068 re = REALPART (z);
1069 im = IMAGPART (z);
1070 if (im == 0)
1072 if (re < 0)
1074 COMPLEX_ASSIGN (v, 0, copysignf (sqrtf (-re), im));
1076 else
1078 COMPLEX_ASSIGN (v, fabsf (sqrtf (re)), copysignf (0, im));
1081 else if (re == 0)
1083 float r;
1085 r = sqrtf (0.5 * fabsf (im));
1087 COMPLEX_ASSIGN (v, r, copysignf (r, im));
1089 else
1091 float d, r, s;
1093 d = hypotf (re, im);
1094 /* Use the identity 2 Re res Im res = Im x
1095 to avoid cancellation error in d +/- Re x. */
1096 if (re > 0)
1098 r = sqrtf (0.5 * d + 0.5 * re);
1099 s = (0.5 * im) / r;
1101 else
1103 s = sqrtf (0.5 * d - 0.5 * re);
1104 r = fabsf ((0.5 * im) / s);
1107 COMPLEX_ASSIGN (v, r, copysignf (s, im));
1109 return v;
1111 #endif
1113 #if !defined(HAVE_CSQRT)
1114 #define HAVE_CSQRT 1
1115 double complex csqrt (double complex z);
1117 double complex
1118 csqrt (double complex z)
1120 double re, im;
1121 double complex v;
1123 re = REALPART (z);
1124 im = IMAGPART (z);
1125 if (im == 0)
1127 if (re < 0)
1129 COMPLEX_ASSIGN (v, 0, copysign (sqrt (-re), im));
1131 else
1133 COMPLEX_ASSIGN (v, fabs (sqrt (re)), copysign (0, im));
1136 else if (re == 0)
1138 double r;
1140 r = sqrt (0.5 * fabs (im));
1142 COMPLEX_ASSIGN (v, r, copysign (r, im));
1144 else
1146 double d, r, s;
1148 d = hypot (re, im);
1149 /* Use the identity 2 Re res Im res = Im x
1150 to avoid cancellation error in d +/- Re x. */
1151 if (re > 0)
1153 r = sqrt (0.5 * d + 0.5 * re);
1154 s = (0.5 * im) / r;
1156 else
1158 s = sqrt (0.5 * d - 0.5 * re);
1159 r = fabs ((0.5 * im) / s);
1162 COMPLEX_ASSIGN (v, r, copysign (s, im));
1164 return v;
1166 #endif
1168 #if !defined(HAVE_CSQRTL) && defined(HAVE_COPYSIGNL) && defined(HAVE_SQRTL) && defined(HAVE_FABSL) && defined(HAVE_HYPOTL)
1169 #define HAVE_CSQRTL 1
1170 long double complex csqrtl (long double complex z);
1172 long double complex
1173 csqrtl (long double complex z)
1175 long double re, im;
1176 long double complex v;
1178 re = REALPART (z);
1179 im = IMAGPART (z);
1180 if (im == 0)
1182 if (re < 0)
1184 COMPLEX_ASSIGN (v, 0, copysignl (sqrtl (-re), im));
1186 else
1188 COMPLEX_ASSIGN (v, fabsl (sqrtl (re)), copysignl (0, im));
1191 else if (re == 0)
1193 long double r;
1195 r = sqrtl (0.5 * fabsl (im));
1197 COMPLEX_ASSIGN (v, copysignl (r, im), r);
1199 else
1201 long double d, r, s;
1203 d = hypotl (re, im);
1204 /* Use the identity 2 Re res Im res = Im x
1205 to avoid cancellation error in d +/- Re x. */
1206 if (re > 0)
1208 r = sqrtl (0.5 * d + 0.5 * re);
1209 s = (0.5 * im) / r;
1211 else
1213 s = sqrtl (0.5 * d - 0.5 * re);
1214 r = fabsl ((0.5 * im) / s);
1217 COMPLEX_ASSIGN (v, r, copysignl (s, im));
1219 return v;
1221 #endif
1224 /* sinh(a + i b) = sinh(a) cos(b) + i cosh(a) sin(b) */
1225 #if !defined(HAVE_CSINHF)
1226 #define HAVE_CSINHF 1
1227 float complex csinhf (float complex a);
1229 float complex
1230 csinhf (float complex a)
1232 float r, i;
1233 float complex v;
1235 r = REALPART (a);
1236 i = IMAGPART (a);
1237 COMPLEX_ASSIGN (v, sinhf (r) * cosf (i), coshf (r) * sinf (i));
1238 return v;
1240 #endif
1242 #if !defined(HAVE_CSINH)
1243 #define HAVE_CSINH 1
1244 double complex csinh (double complex a);
1246 double complex
1247 csinh (double complex a)
1249 double r, i;
1250 double complex v;
1252 r = REALPART (a);
1253 i = IMAGPART (a);
1254 COMPLEX_ASSIGN (v, sinh (r) * cos (i), cosh (r) * sin (i));
1255 return v;
1257 #endif
1259 #if !defined(HAVE_CSINHL) && defined(HAVE_COSL) && defined(HAVE_COSHL) && defined(HAVE_SINL) && defined(HAVE_SINHL)
1260 #define HAVE_CSINHL 1
1261 long double complex csinhl (long double complex a);
1263 long double complex
1264 csinhl (long double complex a)
1266 long double r, i;
1267 long double complex v;
1269 r = REALPART (a);
1270 i = IMAGPART (a);
1271 COMPLEX_ASSIGN (v, sinhl (r) * cosl (i), coshl (r) * sinl (i));
1272 return v;
1274 #endif
1277 /* cosh(a + i b) = cosh(a) cos(b) + i sinh(a) sin(b) */
1278 #if !defined(HAVE_CCOSHF)
1279 #define HAVE_CCOSHF 1
1280 float complex ccoshf (float complex a);
1282 float complex
1283 ccoshf (float complex a)
1285 float r, i;
1286 float complex v;
1288 r = REALPART (a);
1289 i = IMAGPART (a);
1290 COMPLEX_ASSIGN (v, coshf (r) * cosf (i), sinhf (r) * sinf (i));
1291 return v;
1293 #endif
1295 #if !defined(HAVE_CCOSH)
1296 #define HAVE_CCOSH 1
1297 double complex ccosh (double complex a);
1299 double complex
1300 ccosh (double complex a)
1302 double r, i;
1303 double complex v;
1305 r = REALPART (a);
1306 i = IMAGPART (a);
1307 COMPLEX_ASSIGN (v, cosh (r) * cos (i), sinh (r) * sin (i));
1308 return v;
1310 #endif
1312 #if !defined(HAVE_CCOSHL) && defined(HAVE_COSL) && defined(HAVE_COSHL) && defined(HAVE_SINL) && defined(HAVE_SINHL)
1313 #define HAVE_CCOSHL 1
1314 long double complex ccoshl (long double complex a);
1316 long double complex
1317 ccoshl (long double complex a)
1319 long double r, i;
1320 long double complex v;
1322 r = REALPART (a);
1323 i = IMAGPART (a);
1324 COMPLEX_ASSIGN (v, coshl (r) * cosl (i), sinhl (r) * sinl (i));
1325 return v;
1327 #endif
1330 /* tanh(a + i b) = (tanh(a) + i tan(b)) / (1 + i tanh(a) tan(b)) */
1331 #if !defined(HAVE_CTANHF)
1332 #define HAVE_CTANHF 1
1333 float complex ctanhf (float complex a);
1335 float complex
1336 ctanhf (float complex a)
1338 float rt, it;
1339 float complex n, d;
1341 rt = tanhf (REALPART (a));
1342 it = tanf (IMAGPART (a));
1343 COMPLEX_ASSIGN (n, rt, it);
1344 COMPLEX_ASSIGN (d, 1, rt * it);
1346 return n / d;
1348 #endif
1350 #if !defined(HAVE_CTANH)
1351 #define HAVE_CTANH 1
1352 double complex ctanh (double complex a);
1353 double complex
1354 ctanh (double complex a)
1356 double rt, it;
1357 double complex n, d;
1359 rt = tanh (REALPART (a));
1360 it = tan (IMAGPART (a));
1361 COMPLEX_ASSIGN (n, rt, it);
1362 COMPLEX_ASSIGN (d, 1, rt * it);
1364 return n / d;
1366 #endif
1368 #if !defined(HAVE_CTANHL) && defined(HAVE_TANL) && defined(HAVE_TANHL)
1369 #define HAVE_CTANHL 1
1370 long double complex ctanhl (long double complex a);
1372 long double complex
1373 ctanhl (long double complex a)
1375 long double rt, it;
1376 long double complex n, d;
1378 rt = tanhl (REALPART (a));
1379 it = tanl (IMAGPART (a));
1380 COMPLEX_ASSIGN (n, rt, it);
1381 COMPLEX_ASSIGN (d, 1, rt * it);
1383 return n / d;
1385 #endif
1388 /* sin(a + i b) = sin(a) cosh(b) + i cos(a) sinh(b) */
1389 #if !defined(HAVE_CSINF)
1390 #define HAVE_CSINF 1
1391 float complex csinf (float complex a);
1393 float complex
1394 csinf (float complex a)
1396 float r, i;
1397 float complex v;
1399 r = REALPART (a);
1400 i = IMAGPART (a);
1401 COMPLEX_ASSIGN (v, sinf (r) * coshf (i), cosf (r) * sinhf (i));
1402 return v;
1404 #endif
1406 #if !defined(HAVE_CSIN)
1407 #define HAVE_CSIN 1
1408 double complex csin (double complex a);
1410 double complex
1411 csin (double complex a)
1413 double r, i;
1414 double complex v;
1416 r = REALPART (a);
1417 i = IMAGPART (a);
1418 COMPLEX_ASSIGN (v, sin (r) * cosh (i), cos (r) * sinh (i));
1419 return v;
1421 #endif
1423 #if !defined(HAVE_CSINL) && defined(HAVE_COSL) && defined(HAVE_COSHL) && defined(HAVE_SINL) && defined(HAVE_SINHL)
1424 #define HAVE_CSINL 1
1425 long double complex csinl (long double complex a);
1427 long double complex
1428 csinl (long double complex a)
1430 long double r, i;
1431 long double complex v;
1433 r = REALPART (a);
1434 i = IMAGPART (a);
1435 COMPLEX_ASSIGN (v, sinl (r) * coshl (i), cosl (r) * sinhl (i));
1436 return v;
1438 #endif
1441 /* cos(a + i b) = cos(a) cosh(b) - i sin(a) sinh(b) */
1442 #if !defined(HAVE_CCOSF)
1443 #define HAVE_CCOSF 1
1444 float complex ccosf (float complex a);
1446 float complex
1447 ccosf (float complex a)
1449 float r, i;
1450 float complex v;
1452 r = REALPART (a);
1453 i = IMAGPART (a);
1454 COMPLEX_ASSIGN (v, cosf (r) * coshf (i), - (sinf (r) * sinhf (i)));
1455 return v;
1457 #endif
1459 #if !defined(HAVE_CCOS)
1460 #define HAVE_CCOS 1
1461 double complex ccos (double complex a);
1463 double complex
1464 ccos (double complex a)
1466 double r, i;
1467 double complex v;
1469 r = REALPART (a);
1470 i = IMAGPART (a);
1471 COMPLEX_ASSIGN (v, cos (r) * cosh (i), - (sin (r) * sinh (i)));
1472 return v;
1474 #endif
1476 #if !defined(HAVE_CCOSL) && defined(HAVE_COSL) && defined(HAVE_COSHL) && defined(HAVE_SINL) && defined(HAVE_SINHL)
1477 #define HAVE_CCOSL 1
1478 long double complex ccosl (long double complex a);
1480 long double complex
1481 ccosl (long double complex a)
1483 long double r, i;
1484 long double complex v;
1486 r = REALPART (a);
1487 i = IMAGPART (a);
1488 COMPLEX_ASSIGN (v, cosl (r) * coshl (i), - (sinl (r) * sinhl (i)));
1489 return v;
1491 #endif
1494 /* tan(a + i b) = (tan(a) + i tanh(b)) / (1 - i tan(a) tanh(b)) */
1495 #if !defined(HAVE_CTANF)
1496 #define HAVE_CTANF 1
1497 float complex ctanf (float complex a);
1499 float complex
1500 ctanf (float complex a)
1502 float rt, it;
1503 float complex n, d;
1505 rt = tanf (REALPART (a));
1506 it = tanhf (IMAGPART (a));
1507 COMPLEX_ASSIGN (n, rt, it);
1508 COMPLEX_ASSIGN (d, 1, - (rt * it));
1510 return n / d;
1512 #endif
1514 #if !defined(HAVE_CTAN)
1515 #define HAVE_CTAN 1
1516 double complex ctan (double complex a);
1518 double complex
1519 ctan (double complex a)
1521 double rt, it;
1522 double complex n, d;
1524 rt = tan (REALPART (a));
1525 it = tanh (IMAGPART (a));
1526 COMPLEX_ASSIGN (n, rt, it);
1527 COMPLEX_ASSIGN (d, 1, - (rt * it));
1529 return n / d;
1531 #endif
1533 #if !defined(HAVE_CTANL) && defined(HAVE_TANL) && defined(HAVE_TANHL)
1534 #define HAVE_CTANL 1
1535 long double complex ctanl (long double complex a);
1537 long double complex
1538 ctanl (long double complex a)
1540 long double rt, it;
1541 long double complex n, d;
1543 rt = tanl (REALPART (a));
1544 it = tanhl (IMAGPART (a));
1545 COMPLEX_ASSIGN (n, rt, it);
1546 COMPLEX_ASSIGN (d, 1, - (rt * it));
1548 return n / d;
1550 #endif
1553 /* Complex ASIN. Returns wrongly NaN for infinite arguments.
1554 Algorithm taken from Abramowitz & Stegun. */
1556 #if !defined(HAVE_CASINF) && defined(HAVE_CLOGF) && defined(HAVE_CSQRTF)
1557 #define HAVE_CASINF 1
1558 complex float casinf (complex float z);
1560 complex float
1561 casinf (complex float z)
1563 return -I*clogf (I*z + csqrtf (1.0f-z*z));
1565 #endif
1568 #if !defined(HAVE_CASIN) && defined(HAVE_CLOG) && defined(HAVE_CSQRT)
1569 #define HAVE_CASIN 1
1570 complex double casin (complex double z);
1572 complex double
1573 casin (complex double z)
1575 return -I*clog (I*z + csqrt (1.0-z*z));
1577 #endif
1580 #if !defined(HAVE_CASINL) && defined(HAVE_CLOGL) && defined(HAVE_CSQRTL)
1581 #define HAVE_CASINL 1
1582 complex long double casinl (complex long double z);
1584 complex long double
1585 casinl (complex long double z)
1587 return -I*clogl (I*z + csqrtl (1.0L-z*z));
1589 #endif
1592 /* Complex ACOS. Returns wrongly NaN for infinite arguments.
1593 Algorithm taken from Abramowitz & Stegun. */
1595 #if !defined(HAVE_CACOSF) && defined(HAVE_CLOGF) && defined(HAVE_CSQRTF)
1596 #define HAVE_CACOSF 1
1597 complex float cacosf (complex float z);
1599 complex float
1600 cacosf (complex float z)
1602 return -I*clogf (z + I*csqrtf (1.0f-z*z));
1604 #endif
1607 #if !defined(HAVE_CACOS) && defined(HAVE_CLOG) && defined(HAVE_CSQRT)
1608 #define HAVE_CACOS 1
1609 complex double cacos (complex double z);
1611 complex double
1612 cacos (complex double z)
1614 return -I*clog (z + I*csqrt (1.0-z*z));
1616 #endif
1619 #if !defined(HAVE_CACOSL) && defined(HAVE_CLOGL) && defined(HAVE_CSQRTL)
1620 #define HAVE_CACOSL 1
1621 complex long double cacosl (complex long double z);
1623 complex long double
1624 cacosl (complex long double z)
1626 return -I*clogl (z + I*csqrtl (1.0L-z*z));
1628 #endif
1631 /* Complex ATAN. Returns wrongly NaN for infinite arguments.
1632 Algorithm taken from Abramowitz & Stegun. */
1634 #if !defined(HAVE_CATANF) && defined(HAVE_CLOGF)
1635 #define HAVE_CACOSF 1
1636 complex float catanf (complex float z);
1638 complex float
1639 catanf (complex float z)
1641 return I*clogf ((I+z)/(I-z))/2.0f;
1643 #endif
1646 #if !defined(HAVE_CATAN) && defined(HAVE_CLOG)
1647 #define HAVE_CACOS 1
1648 complex double catan (complex double z);
1650 complex double
1651 catan (complex double z)
1653 return I*clog ((I+z)/(I-z))/2.0;
1655 #endif
1658 #if !defined(HAVE_CATANL) && defined(HAVE_CLOGL)
1659 #define HAVE_CACOSL 1
1660 complex long double catanl (complex long double z);
1662 complex long double
1663 catanl (complex long double z)
1665 return I*clogl ((I+z)/(I-z))/2.0L;
1667 #endif
1670 /* Complex ASINH. Returns wrongly NaN for infinite arguments.
1671 Algorithm taken from Abramowitz & Stegun. */
1673 #if !defined(HAVE_CASINHF) && defined(HAVE_CLOGF) && defined(HAVE_CSQRTF)
1674 #define HAVE_CASINHF 1
1675 complex float casinhf (complex float z);
1677 complex float
1678 casinhf (complex float z)
1680 return clogf (z + csqrtf (z*z+1.0f));
1682 #endif
1685 #if !defined(HAVE_CASINH) && defined(HAVE_CLOG) && defined(HAVE_CSQRT)
1686 #define HAVE_CASINH 1
1687 complex double casinh (complex double z);
1689 complex double
1690 casinh (complex double z)
1692 return clog (z + csqrt (z*z+1.0));
1694 #endif
1697 #if !defined(HAVE_CASINHL) && defined(HAVE_CLOGL) && defined(HAVE_CSQRTL)
1698 #define HAVE_CASINHL 1
1699 complex long double casinhl (complex long double z);
1701 complex long double
1702 casinhl (complex long double z)
1704 return clogl (z + csqrtl (z*z+1.0L));
1706 #endif
1709 /* Complex ACOSH. Returns wrongly NaN for infinite arguments.
1710 Algorithm taken from Abramowitz & Stegun. */
1712 #if !defined(HAVE_CACOSHF) && defined(HAVE_CLOGF) && defined(HAVE_CSQRTF)
1713 #define HAVE_CACOSHF 1
1714 complex float cacoshf (complex float z);
1716 complex float
1717 cacoshf (complex float z)
1719 return clogf (z + csqrtf (z-1.0f) * csqrtf (z+1.0f));
1721 #endif
1724 #if !defined(HAVE_CACOSH) && defined(HAVE_CLOG) && defined(HAVE_CSQRT)
1725 #define HAVE_CACOSH 1
1726 complex double cacosh (complex double z);
1728 complex double
1729 cacosh (complex double z)
1731 return clog (z + csqrt (z-1.0) * csqrt (z+1.0));
1733 #endif
1736 #if !defined(HAVE_CACOSHL) && defined(HAVE_CLOGL) && defined(HAVE_CSQRTL)
1737 #define HAVE_CACOSHL 1
1738 complex long double cacoshl (complex long double z);
1740 complex long double
1741 cacoshl (complex long double z)
1743 return clogl (z + csqrtl (z-1.0L) * csqrtl (z+1.0L));
1745 #endif
1748 /* Complex ATANH. Returns wrongly NaN for infinite arguments.
1749 Algorithm taken from Abramowitz & Stegun. */
1751 #if !defined(HAVE_CATANHF) && defined(HAVE_CLOGF)
1752 #define HAVE_CATANHF 1
1753 complex float catanhf (complex float z);
1755 complex float
1756 catanhf (complex float z)
1758 return clogf ((1.0f+z)/(1.0f-z))/2.0f;
1760 #endif
1763 #if !defined(HAVE_CATANH) && defined(HAVE_CLOG)
1764 #define HAVE_CATANH 1
1765 complex double catanh (complex double z);
1767 complex double
1768 catanh (complex double z)
1770 return clog ((1.0+z)/(1.0-z))/2.0;
1772 #endif
1774 #if !defined(HAVE_CATANHL) && defined(HAVE_CLOGL)
1775 #define HAVE_CATANHL 1
1776 complex long double catanhl (complex long double z);
1778 complex long double
1779 catanhl (complex long double z)
1781 return clogl ((1.0L+z)/(1.0L-z))/2.0L;
1783 #endif
1786 #if !defined(HAVE_TGAMMA)
1787 #define HAVE_TGAMMA 1
1788 double tgamma (double);
1790 /* Fallback tgamma() function. Uses the algorithm from
1791 http://www.netlib.org/specfun/gamma and references therein. */
1793 #undef SQRTPI
1794 #define SQRTPI 0.9189385332046727417803297
1796 #undef PI
1797 #define PI 3.1415926535897932384626434
1799 double
1800 tgamma (double x)
1802 int i, n, parity;
1803 double fact, res, sum, xden, xnum, y, y1, ysq, z;
1805 static double p[8] = {
1806 -1.71618513886549492533811e0, 2.47656508055759199108314e1,
1807 -3.79804256470945635097577e2, 6.29331155312818442661052e2,
1808 8.66966202790413211295064e2, -3.14512729688483675254357e4,
1809 -3.61444134186911729807069e4, 6.64561438202405440627855e4 };
1811 static double q[8] = {
1812 -3.08402300119738975254353e1, 3.15350626979604161529144e2,
1813 -1.01515636749021914166146e3, -3.10777167157231109440444e3,
1814 2.25381184209801510330112e4, 4.75584627752788110767815e3,
1815 -1.34659959864969306392456e5, -1.15132259675553483497211e5 };
1817 static double c[7] = { -1.910444077728e-03,
1818 8.4171387781295e-04, -5.952379913043012e-04,
1819 7.93650793500350248e-04, -2.777777777777681622553e-03,
1820 8.333333333333333331554247e-02, 5.7083835261e-03 };
1822 static const double xminin = 2.23e-308;
1823 static const double xbig = 171.624;
1824 static const double xnan = __builtin_nan ("0x0"), xinf = __builtin_inf ();
1825 static double eps = 0;
1827 if (eps == 0)
1828 eps = nextafter (1., 2.) - 1.;
1830 parity = 0;
1831 fact = 1;
1832 n = 0;
1833 y = x;
1835 if (isnan (x))
1836 return x;
1838 if (y <= 0)
1840 y = -x;
1841 y1 = trunc (y);
1842 res = y - y1;
1844 if (res != 0)
1846 if (y1 != trunc (y1*0.5l)*2)
1847 parity = 1;
1848 fact = -PI / sin (PI*res);
1849 y = y + 1;
1851 else
1852 return x == 0 ? copysign (xinf, x) : xnan;
1855 if (y < eps)
1857 if (y >= xminin)
1858 res = 1 / y;
1859 else
1860 return xinf;
1862 else if (y < 13)
1864 y1 = y;
1865 if (y < 1)
1867 z = y;
1868 y = y + 1;
1870 else
1872 n = (int)y - 1;
1873 y = y - n;
1874 z = y - 1;
1877 xnum = 0;
1878 xden = 1;
1879 for (i = 0; i < 8; i++)
1881 xnum = (xnum + p[i]) * z;
1882 xden = xden * z + q[i];
1885 res = xnum / xden + 1;
1887 if (y1 < y)
1888 res = res / y1;
1889 else if (y1 > y)
1890 for (i = 1; i <= n; i++)
1892 res = res * y;
1893 y = y + 1;
1896 else
1898 if (y < xbig)
1900 ysq = y * y;
1901 sum = c[6];
1902 for (i = 0; i < 6; i++)
1903 sum = sum / ysq + c[i];
1905 sum = sum/y - y + SQRTPI;
1906 sum = sum + (y - 0.5) * log (y);
1907 res = exp (sum);
1909 else
1910 return x < 0 ? xnan : xinf;
1913 if (parity)
1914 res = -res;
1915 if (fact != 1)
1916 res = fact / res;
1918 return res;
1920 #endif
1924 #if !defined(HAVE_LGAMMA)
1925 #define HAVE_LGAMMA 1
1926 double lgamma (double);
1928 /* Fallback lgamma() function. Uses the algorithm from
1929 http://www.netlib.org/specfun/algama and references therein,
1930 except for negative arguments (where netlib would return +Inf)
1931 where we use the following identity:
1932 lgamma(y) = log(pi/(|y*sin(pi*y)|)) - lgamma(-y)
1935 double
1936 lgamma (double y)
1939 #undef SQRTPI
1940 #define SQRTPI 0.9189385332046727417803297
1942 #undef PI
1943 #define PI 3.1415926535897932384626434
1945 #define PNT68 0.6796875
1946 #define D1 -0.5772156649015328605195174
1947 #define D2 0.4227843350984671393993777
1948 #define D4 1.791759469228055000094023
1950 static double p1[8] = {
1951 4.945235359296727046734888e0, 2.018112620856775083915565e2,
1952 2.290838373831346393026739e3, 1.131967205903380828685045e4,
1953 2.855724635671635335736389e4, 3.848496228443793359990269e4,
1954 2.637748787624195437963534e4, 7.225813979700288197698961e3 };
1955 static double q1[8] = {
1956 6.748212550303777196073036e1, 1.113332393857199323513008e3,
1957 7.738757056935398733233834e3, 2.763987074403340708898585e4,
1958 5.499310206226157329794414e4, 6.161122180066002127833352e4,
1959 3.635127591501940507276287e4, 8.785536302431013170870835e3 };
1960 static double p2[8] = {
1961 4.974607845568932035012064e0, 5.424138599891070494101986e2,
1962 1.550693864978364947665077e4, 1.847932904445632425417223e5,
1963 1.088204769468828767498470e6, 3.338152967987029735917223e6,
1964 5.106661678927352456275255e6, 3.074109054850539556250927e6 };
1965 static double q2[8] = {
1966 1.830328399370592604055942e2, 7.765049321445005871323047e3,
1967 1.331903827966074194402448e5, 1.136705821321969608938755e6,
1968 5.267964117437946917577538e6, 1.346701454311101692290052e7,
1969 1.782736530353274213975932e7, 9.533095591844353613395747e6 };
1970 static double p4[8] = {
1971 1.474502166059939948905062e4, 2.426813369486704502836312e6,
1972 1.214755574045093227939592e8, 2.663432449630976949898078e9,
1973 2.940378956634553899906876e10, 1.702665737765398868392998e11,
1974 4.926125793377430887588120e11, 5.606251856223951465078242e11 };
1975 static double q4[8] = {
1976 2.690530175870899333379843e3, 6.393885654300092398984238e5,
1977 4.135599930241388052042842e7, 1.120872109616147941376570e9,
1978 1.488613728678813811542398e10, 1.016803586272438228077304e11,
1979 3.417476345507377132798597e11, 4.463158187419713286462081e11 };
1980 static double c[7] = {
1981 -1.910444077728e-03, 8.4171387781295e-04,
1982 -5.952379913043012e-04, 7.93650793500350248e-04,
1983 -2.777777777777681622553e-03, 8.333333333333333331554247e-02,
1984 5.7083835261e-03 };
1986 static double xbig = 2.55e305, xinf = __builtin_inf (), eps = 0,
1987 frtbig = 2.25e76;
1989 int i;
1990 double corr, res, xden, xm1, xm2, xm4, xnum, ysq;
1992 if (eps == 0)
1993 eps = __builtin_nextafter (1., 2.) - 1.;
1995 if ((y > 0) && (y <= xbig))
1997 if (y <= eps)
1998 res = -log (y);
1999 else if (y <= 1.5)
2001 if (y < PNT68)
2003 corr = -log (y);
2004 xm1 = y;
2006 else
2008 corr = 0;
2009 xm1 = (y - 0.5) - 0.5;
2012 if ((y <= 0.5) || (y >= PNT68))
2014 xden = 1;
2015 xnum = 0;
2016 for (i = 0; i < 8; i++)
2018 xnum = xnum*xm1 + p1[i];
2019 xden = xden*xm1 + q1[i];
2021 res = corr + (xm1 * (D1 + xm1*(xnum/xden)));
2023 else
2025 xm2 = (y - 0.5) - 0.5;
2026 xden = 1;
2027 xnum = 0;
2028 for (i = 0; i < 8; i++)
2030 xnum = xnum*xm2 + p2[i];
2031 xden = xden*xm2 + q2[i];
2033 res = corr + xm2 * (D2 + xm2*(xnum/xden));
2036 else if (y <= 4)
2038 xm2 = y - 2;
2039 xden = 1;
2040 xnum = 0;
2041 for (i = 0; i < 8; i++)
2043 xnum = xnum*xm2 + p2[i];
2044 xden = xden*xm2 + q2[i];
2046 res = xm2 * (D2 + xm2*(xnum/xden));
2048 else if (y <= 12)
2050 xm4 = y - 4;
2051 xden = -1;
2052 xnum = 0;
2053 for (i = 0; i < 8; i++)
2055 xnum = xnum*xm4 + p4[i];
2056 xden = xden*xm4 + q4[i];
2058 res = D4 + xm4*(xnum/xden);
2060 else
2062 res = 0;
2063 if (y <= frtbig)
2065 res = c[6];
2066 ysq = y * y;
2067 for (i = 0; i < 6; i++)
2068 res = res / ysq + c[i];
2070 res = res/y;
2071 corr = log (y);
2072 res = res + SQRTPI - 0.5*corr;
2073 res = res + y*(corr-1);
2076 else if (y < 0 && __builtin_floor (y) != y)
2078 /* lgamma(y) = log(pi/(|y*sin(pi*y)|)) - lgamma(-y)
2079 For abs(y) very close to zero, we use a series expansion to
2080 the first order in y to avoid overflow. */
2081 if (y > -1.e-100)
2082 res = -2 * log (fabs (y)) - lgamma (-y);
2083 else
2084 res = log (PI / fabs (y * sin (PI * y))) - lgamma (-y);
2086 else
2087 res = xinf;
2089 return res;
2091 #endif
2094 #if defined(HAVE_TGAMMA) && !defined(HAVE_TGAMMAF)
2095 #define HAVE_TGAMMAF 1
2096 float tgammaf (float);
2098 float
2099 tgammaf (float x)
2101 return (float) tgamma ((double) x);
2103 #endif
2105 #if defined(HAVE_LGAMMA) && !defined(HAVE_LGAMMAF)
2106 #define HAVE_LGAMMAF 1
2107 float lgammaf (float);
2109 float
2110 lgammaf (float x)
2112 return (float) lgamma ((double) x);
2114 #endif