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/* ===-- divdc3.c - Implement __divdc3 -------------------------------------===
*
* 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 __divdc3 for the compiler_rt library.
*
* ===----------------------------------------------------------------------===
*/
#include "int_lib.h"
#include "int_math.h"
/* Returns: the quotient of (a + ib) / (c + id) */
COMPILER_RT_ABI Dcomplex
__divdc3(double __a, double __b, double __c, double __d)
{
int __ilogbw = 0;
double __logbw = crt_logb(crt_fmax(crt_fabs(__c), crt_fabs(__d)));
if (crt_isfinite(__logbw))
{
__ilogbw = (int)__logbw;
__c = crt_scalbn(__c, -__ilogbw);
__d = crt_scalbn(__d, -__ilogbw);
}
double __denom = __c * __c + __d * __d;
Dcomplex z;
COMPLEX_REAL(z) = crt_scalbn((__a * __c + __b * __d) / __denom, -__ilogbw);
COMPLEX_IMAGINARY(z) = crt_scalbn((__b * __c - __a * __d) / __denom, -__ilogbw);
if (crt_isnan(COMPLEX_REAL(z)) && crt_isnan(COMPLEX_IMAGINARY(z)))
{
if ((__denom == 0.0) && (!crt_isnan(__a) || !crt_isnan(__b)))
{
COMPLEX_REAL(z) = crt_copysign(CRT_INFINITY, __c) * __a;
COMPLEX_IMAGINARY(z) = crt_copysign(CRT_INFINITY, __c) * __b;
}
else if ((crt_isinf(__a) || crt_isinf(__b)) &&
crt_isfinite(__c) && crt_isfinite(__d))
{
__a = crt_copysign(crt_isinf(__a) ? 1.0 : 0.0, __a);
__b = crt_copysign(crt_isinf(__b) ? 1.0 : 0.0, __b);
COMPLEX_REAL(z) = CRT_INFINITY * (__a * __c + __b * __d);
COMPLEX_IMAGINARY(z) = CRT_INFINITY * (__b * __c - __a * __d);
}
else if (crt_isinf(__logbw) && __logbw > 0.0 &&
crt_isfinite(__a) && crt_isfinite(__b))
{
__c = crt_copysign(crt_isinf(__c) ? 1.0 : 0.0, __c);
__d = crt_copysign(crt_isinf(__d) ? 1.0 : 0.0, __d);
COMPLEX_REAL(z) = 0.0 * (__a * __c + __b * __d);
COMPLEX_IMAGINARY(z) = 0.0 * (__b * __c - __a * __d);
}
}
return z;
}
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