1 /* Copyright (C) 1997 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Library General Public License as
6 published by the Free Software Foundation; either version 2 of the
7 License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Library General Public License for more details.
14 You should have received a copy of the GNU Library General Public
15 License along with the GNU C Library; see the file COPYING.LIB. If not,
16 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 Boston, MA 02111-1307, USA. */
19 #define __LIBC_INTERNAL_MATH_INLINES
21 #include "math_private.h"
27 #define float_type double
30 #define CONCATX(a,b) __CONCAT(a,b)
31 #define s(name) CONCATX(name,SUFF)
32 #define m81(func) __m81_u(s(func))
35 s(__ieee754_atan2) (float_type y, float_type x)
37 float_type pi, pi_2, z;
38 unsigned long y_cond, x_cond;
40 __asm ("fmovecr%.x %#0, %0" : "=f" (pi));
41 __asm ("fscale%.w %#-1, %0" : "=f" (pi_2) : "0" (pi));
42 y_cond = __m81_test (y);
43 x_cond = __m81_test (x);
45 if ((x_cond | y_cond) & __M81_COND_NAN)
47 else if (y_cond & __M81_COND_ZERO)
49 if (x_cond & __M81_COND_NEG)
50 z = y_cond & __M81_COND_NEG ? -pi : pi;
54 else if (x_cond & __M81_COND_INF)
56 if (y_cond & __M81_COND_INF)
59 __asm ("fscale%.w %#-2, %0" : "=f" (pi_4) : "0" (pi));
60 z = x_cond & __M81_COND_NEG ? 3 * pi_4 : pi_4;
63 z = x_cond & __M81_COND_NEG ? pi : 0;
64 if (y_cond & __M81_COND_NEG)
67 else if (y_cond & __M81_COND_INF)
68 z = y_cond & __M81_COND_NEG ? -pi_2 : pi_2;
69 else if (x_cond & __M81_COND_NEG)
71 if (y_cond & __M81_COND_NEG)
74 z = -pi + m81(__atan) (y / x);
76 z = -pi_2 - m81(__atan) (x / y);
81 z = pi + m81(__atan) (y / x);
83 z = pi_2 - m81(__atan) (x / y);
88 if (y_cond & __M81_COND_NEG)
91 z = m81(__atan) (y / x);
93 z = -pi_2 - m81(__atan) (x / y);
98 z = m81(__atan) (y / x);
100 z = pi_2 - m81(__atan) (x / y);