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/* Copyright (C) 1989-2017 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 isnan __builtin_isnan
#define isinf __builtin_isinf
KCtype
__mulkc3 (KFtype a, KFtype b, KFtype c, KFtype d)
{
KFtype ac, bd, ad, bc, x, y;
KCtype res;
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 = COPYSIGN (isinf (a) ? 1 : 0, a);
b = COPYSIGN (isinf (b) ? 1 : 0, b);
if (isnan (c)) c = COPYSIGN (0, c);
if (isnan (d)) d = COPYSIGN (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 = COPYSIGN (isinf (c) ? 1 : 0, c);
d = COPYSIGN (isinf (d) ? 1 : 0, d);
if (isnan (a)) a = COPYSIGN (0, a);
if (isnan (b)) b = COPYSIGN (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 = COPYSIGN (0, a);
if (isnan (b)) b = COPYSIGN (0, b);
if (isnan (c)) c = COPYSIGN (0, c);
if (isnan (d)) d = COPYSIGN (0, d);
recalc = 1;
}
if (recalc)
{
x = INFINITY * (a * c - b * d);
y = INFINITY * (a * d + b * c);
}
}
__real__ res = x;
__imag__ res = y;
return res;
}
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