llvm-project/compiler-rt/lib/builtins/multc3.c

69 lines
2.2 KiB
C

/* ===-- multc3.c - Implement __multc3 -------------------------------------===
*
* The LLVM Compiler Infrastructure
*
* This file is dual licensed under the MIT and the University of Illinois Open
* Source Licenses. See LICENSE.TXT for details.
*
* ===----------------------------------------------------------------------===
*
* This file implements __multc3 for the compiler_rt library.
*
* ===----------------------------------------------------------------------===
*/
#include "int_lib.h"
#include "int_math.h"
/* Returns: the product of a + ib and c + id */
COMPILER_RT_ABI long double _Complex
__multc3(long double a, long double b, long double c, long double d)
{
long double ac = a * c;
long double bd = b * d;
long double ad = a * d;
long double bc = b * c;
long double _Complex z;
__real__ z = ac - bd;
__imag__ z = ad + bc;
if (crt_isnan(__real__ z) && crt_isnan(__imag__ z)) {
int recalc = 0;
if (crt_isinf(a) || crt_isinf(b)) {
a = crt_copysignl(crt_isinf(a) ? 1 : 0, a);
b = crt_copysignl(crt_isinf(b) ? 1 : 0, b);
if (crt_isnan(c))
c = crt_copysignl(0, c);
if (crt_isnan(d))
d = crt_copysignl(0, d);
recalc = 1;
}
if (crt_isinf(c) || crt_isinf(d)) {
c = crt_copysignl(crt_isinf(c) ? 1 : 0, c);
d = crt_copysignl(crt_isinf(d) ? 1 : 0, d);
if (crt_isnan(a))
a = crt_copysignl(0, a);
if (crt_isnan(b))
b = crt_copysignl(0, b);
recalc = 1;
}
if (!recalc && (crt_isinf(ac) || crt_isinf(bd) ||
crt_isinf(ad) || crt_isinf(bc))) {
if (crt_isnan(a))
a = crt_copysignl(0, a);
if (crt_isnan(b))
b = crt_copysignl(0, b);
if (crt_isnan(c))
c = crt_copysignl(0, c);
if (crt_isnan(d))
d = crt_copysignl(0, d);
recalc = 1;
}
if (recalc) {
__real__ z = CRT_INFINITY * (a * c - b * d);
__imag__ z = CRT_INFINITY * (a * d + b * c);
}
}
return z;
}