diff options
Diffstat (limited to 'sysdeps/m68k/fpu/e_atan2.c')
-rw-r--r-- | sysdeps/m68k/fpu/e_atan2.c | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/sysdeps/m68k/fpu/e_atan2.c b/sysdeps/m68k/fpu/e_atan2.c new file mode 100644 index 0000000..551b14d --- /dev/null +++ b/sysdeps/m68k/fpu/e_atan2.c @@ -0,0 +1,104 @@ +/* Copyright (C) 1997, 1999 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <math.h> +#include "math_private.h" +#include "mathimpl.h" + +#ifndef SUFF +#define SUFF +#endif +#ifndef float_type +#define float_type double +#endif + +#define CONCATX(a,b) __CONCAT(a,b) +#define s(name) CONCATX(name,SUFF) +#define m81(func) __m81_u(s(func)) + +float_type +s(__ieee754_atan2) (float_type y, float_type x) +{ + float_type pi, pi_2, z; + unsigned long y_cond, x_cond; + + __asm ("fmovecr%.x %#0, %0" : "=f" (pi)); + __asm ("fscale%.w %#-1, %0" : "=f" (pi_2) : "0" (pi)); + y_cond = __m81_test (y); + x_cond = __m81_test (x); + + if ((x_cond | y_cond) & __M81_COND_NAN) + z = x + y; + else if (y_cond & __M81_COND_ZERO) + { + if (x_cond & __M81_COND_NEG) + z = y_cond & __M81_COND_NEG ? -pi : pi; + else + z = y; + } + else if (x_cond & __M81_COND_INF) + { + if (y_cond & __M81_COND_INF) + { + float_type pi_4; + __asm ("fscale%.w %#-2, %0" : "=f" (pi_4) : "0" (pi)); + z = x_cond & __M81_COND_NEG ? 3 * pi_4 : pi_4; + } + else + z = x_cond & __M81_COND_NEG ? pi : 0; + if (y_cond & __M81_COND_NEG) + z = -z; + } + else if (y_cond & __M81_COND_INF) + z = y_cond & __M81_COND_NEG ? -pi_2 : pi_2; + else if (x_cond & __M81_COND_NEG) + { + if (y_cond & __M81_COND_NEG) + { + if (-x > -y) + z = -pi + m81(__atan) (y / x); + else + z = -pi_2 - m81(__atan) (x / y); + } + else + { + if (-x > y) + z = pi + m81(__atan) (y / x); + else + z = pi_2 - m81(__atan) (x / y); + } + } + else + { + if (y_cond & __M81_COND_NEG) + { + if (x > -y) + z = m81(__atan) (y / x); + else + z = -pi_2 - m81(__atan) (x / y); + } + else + { + if (x > y) + z = m81(__atan) (y / x); + else + z = pi_2 - m81(__atan) (x / y); + } + } + return z; +} |