diff options
Diffstat (limited to 'math')
| -rw-r--r-- | math/divtc3.c | 75 | ||||
| -rw-r--r-- | math/multc3.c | 80 |
2 files changed, 155 insertions, 0 deletions
diff --git a/math/divtc3.c b/math/divtc3.c new file mode 100644 index 0000000..d974ae6 --- /dev/null +++ b/math/divtc3.c @@ -0,0 +1,75 @@ +/* Copyright (C) 2005, 2006 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Richard Henderson <rth@redhat.com>, 2005. + + 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 <stdbool.h> +#include <math.h> +#include <complex.h> + +attribute_hidden +long double _Complex +__divtc3 (long double a, long double b, long double c, long double d) +{ + long double denom, ratio, x, y; + + /* ??? We can get better behavior from logarithmic scaling instead of + the division. But that would mean starting to link libgcc against + libm. We could implement something akin to ldexp/frexp as gcc builtins + fairly easily... */ + if (fabsl (c) < fabsl (d)) + { + ratio = c / d; + denom = (c * ratio) + d; + x = ((a * ratio) + b) / denom; + y = ((b * ratio) - a) / denom; + } + else + { + ratio = d / c; + denom = (d * ratio) + c; + x = ((b * ratio) + a) / denom; + y = (b - (a * ratio)) / denom; + } + + /* Recover infinities and zeros that computed as NaN+iNaN; the only cases + are nonzero/zero, infinite/finite, and finite/infinite. */ + if (isnan (x) && isnan (y)) + { + if (denom == 0.0 && (!isnan (a) || !isnan (b))) + { + x = __copysignl (INFINITY, c) * a; + y = __copysignl (INFINITY, c) * b; + } + else if ((isinf (a) || isinf (b)) && isfinite (c) && isfinite (d)) + { + a = __copysignl (isinf (a) ? 1 : 0, a); + b = __copysignl (isinf (b) ? 1 : 0, b); + x = INFINITY * (a * c + b * d); + y = INFINITY * (b * c - a * d); + } + else if ((isinf (c) || isinf (d)) && isfinite (a) && isfinite (b)) + { + c = __copysignl (isinf (c) ? 1 : 0, c); + d = __copysignl (isinf (d) ? 1 : 0, d); + x = 0.0 * (a * c + b * d); + y = 0.0 * (b * c - a * d); + } + } + + return x + I * y; +} diff --git a/math/multc3.c b/math/multc3.c new file mode 100644 index 0000000..6369f48 --- /dev/null +++ b/math/multc3.c @@ -0,0 +1,80 @@ +/* Copyright (C) 2005, 2006 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Richard Henderson <rth@redhat.com>, 2005. + + 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 <stdbool.h> +#include <math.h> +#include <complex.h> + +attribute_hidden +long double _Complex +__multc3 (long double a, long double b, long double c, long double d) +{ + long double ac, bd, ad, bc, x, y; + + ac = a * c; + bd = b * d; + ad = a * d; + bc = b * c; + + x = ac - bd; + y = ad + bc; + + if (isnan (x) && isnan (y)) + { + /* Recover infinities that computed as NaN + iNaN. */ + bool recalc = 0; + if (isinf (a) || isinf (b)) + { + /* z is infinite. "Box" the infinity and change NaNs in + the other factor to 0. */ + a = __copysignl (isinf (a) ? 1 : 0, a); + b = __copysignl (isinf (b) ? 1 : 0, b); + if (isnan (c)) c = __copysignl (0, c); + if (isnan (d)) d = __copysignl (0, d); + recalc = 1; + } + if (isinf (c) || isinf (d)) + { + /* w is infinite. "Box" the infinity and change NaNs in + the other factor to 0. */ + c = __copysignl (isinf (c) ? 1 : 0, c); + d = __copysignl (isinf (d) ? 1 : 0, d); + if (isnan (a)) a = __copysignl (0, a); + if (isnan (b)) b = __copysignl (0, b); + recalc = 1; + } + if (!recalc + && (isinf (ac) || isinf (bd) || isinf (ad) || isinf (bc))) + { + /* Recover infinities from overflow by changing NaNs to 0. */ + if (isnan (a)) a = __copysignl (0, a); + if (isnan (b)) b = __copysignl (0, b); + if (isnan (c)) c = __copysignl (0, c); + if (isnan (d)) d = __copysignl (0, d); + recalc = 1; + } + if (recalc) + { + x = INFINITY * (a * c - b * d); + y = INFINITY * (a * d + b * c); + } + } + + return x + I * y; +} |