From a334319f6530564d22e775935d9c91663623a1b4 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Wed, 22 Dec 2004 20:10:10 +0000 Subject: (CFLAGS-tst-align.c): Add -mpreferred-stack-boundary=4. --- sysdeps/generic/s_csqrtf.c | 112 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 112 insertions(+) create mode 100644 sysdeps/generic/s_csqrtf.c (limited to 'sysdeps/generic/s_csqrtf.c') diff --git a/sysdeps/generic/s_csqrtf.c b/sysdeps/generic/s_csqrtf.c new file mode 100644 index 0000000000..b02c605a37 --- /dev/null +++ b/sysdeps/generic/s_csqrtf.c @@ -0,0 +1,112 @@ +/* Complex square root of float value. + Copyright (C) 1997, 1998 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Based on an algorithm by Stephen L. Moshier . + Contributed by Ulrich Drepper , 1997. + + 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 +#include + +#include "math_private.h" + + +__complex__ float +__csqrtf (__complex__ float x) +{ + __complex__ float res; + int rcls = fpclassify (__real__ x); + int icls = fpclassify (__imag__ x); + + if (rcls <= FP_INFINITE || icls <= FP_INFINITE) + { + if (icls == FP_INFINITE) + { + __real__ res = HUGE_VALF; + __imag__ res = __imag__ x; + } + else if (rcls == FP_INFINITE) + { + if (__real__ x < 0.0) + { + __real__ res = icls == FP_NAN ? __nanf ("") : 0; + __imag__ res = __copysignf (HUGE_VALF, __imag__ x); + } + else + { + __real__ res = __real__ x; + __imag__ res = (icls == FP_NAN + ? __nanf ("") : __copysignf (0.0, __imag__ x)); + } + } + else + { + __real__ res = __nanf (""); + __imag__ res = __nanf (""); + } + } + else + { + if (icls == FP_ZERO) + { + if (__real__ x < 0.0) + { + __real__ res = 0.0; + __imag__ res = __copysignf (__ieee754_sqrtf (-__real__ x), + __imag__ x); + } + else + { + __real__ res = fabsf (__ieee754_sqrtf (__real__ x)); + __imag__ res = __copysignf (0.0, __imag__ x); + } + } + else if (rcls == FP_ZERO) + { + float r = __ieee754_sqrtf (0.5 * fabsf (__imag__ x)); + + __real__ res = __copysignf (r, __imag__ x); + __imag__ res = r; + } + else + { + float d, r, s; + + d = __ieee754_hypotf (__real__ x, __imag__ x); + /* Use the identity 2 Re res Im res = Im x + to avoid cancellation error in d +/- Re x. */ + if (__real__ x > 0) + { + r = __ieee754_sqrtf (0.5f * d + 0.5f * __real__ x); + s = (0.5f * __imag__ x) / r; + } + else + { + s = __ieee754_sqrtf (0.5f * d - 0.5f * __real__ x); + r = fabsf ((0.5f * __imag__ x) / s); + } + + __real__ res = r; + __imag__ res = __copysignf (s, __imag__ x); + } + } + + return res; +} +#ifndef __csqrtf +weak_alias (__csqrtf, csqrtf) +#endif -- cgit 1.4.1