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-rw-r--r--libgcc/config/rs6000/_divkc3.c89
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diff --git a/libgcc/config/rs6000/_divkc3.c b/libgcc/config/rs6000/_divkc3.c
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+/* Copyright (C) 1989-2016 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC 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 General Public License
+for more details.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+<http://www.gnu.org/licenses/>. */
+
+/* This is a temporary specialization of code from libgcc/libgcc2.c. */
+
+typedef float KFtype __attribute__ ((mode (KF)));
+typedef __complex float KCtype __attribute__ ((mode (KC)));
+
+#define COPYSIGN(x,y) __builtin_copysignq (x, y)
+#define INFINITY __builtin_infq ()
+#define FABS __builtin_fabsq
+#define isnan __builtin_isnan
+#define isinf __builtin_isinf
+#define isfinite __builtin_isfinite
+
+KCtype
+__divkc3 (KFtype a, KFtype b, KFtype c, KFtype d)
+{
+ KFtype denom, ratio, x, y;
+ KCtype res;
+
+ /* ??? 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 (FABS (c) < FABS (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 (c == 0.0 && d == 0.0 && (!isnan (a) || !isnan (b)))
+ {
+ x = COPYSIGN (INFINITY, c) * a;
+ y = COPYSIGN (INFINITY, c) * b;
+ }
+ else if ((isinf (a) || isinf (b)) && isfinite (c) && isfinite (d))
+ {
+ a = COPYSIGN (isinf (a) ? 1 : 0, a);
+ b = COPYSIGN (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 = COPYSIGN (isinf (c) ? 1 : 0, c);
+ d = COPYSIGN (isinf (d) ? 1 : 0, d);
+ x = 0.0 * (a * c + b * d);
+ y = 0.0 * (b * c - a * d);
+ }
+ }
+
+ __real__ res = x;
+ __imag__ res = y;
+ return res;
+}