llvm-project/compiler-rt/lib/builtins/divsc3.c

61 lines
2.2 KiB
C

/*===-- divsc3.c - Implement __divsc3 -------------------------------------===
*
* 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 __divsc3 for the compiler_rt library.
*
*===----------------------------------------------------------------------===
*/
#include "int_lib.h"
#include "int_math.h"
/* Returns: the quotient of (a + ib) / (c + id) */
COMPILER_RT_ABI Fcomplex
__divsc3(float __a, float __b, float __c, float __d)
{
int __ilogbw = 0;
float __logbw = crt_logbf(crt_fmaxf(crt_fabsf(__c), crt_fabsf(__d)));
if (crt_isfinite(__logbw))
{
__ilogbw = (int)__logbw;
__c = crt_scalbnf(__c, -__ilogbw);
__d = crt_scalbnf(__d, -__ilogbw);
}
float __denom = __c * __c + __d * __d;
Fcomplex z;
COMPLEX_REAL(z) = crt_scalbnf((__a * __c + __b * __d) / __denom, -__ilogbw);
COMPLEX_IMAGINARY(z) = crt_scalbnf((__b * __c - __a * __d) / __denom, -__ilogbw);
if (crt_isnan(COMPLEX_REAL(z)) && crt_isnan(COMPLEX_IMAGINARY(z)))
{
if ((__denom == 0) && (!crt_isnan(__a) || !crt_isnan(__b)))
{
COMPLEX_REAL(z) = crt_copysignf(CRT_INFINITY, __c) * __a;
COMPLEX_IMAGINARY(z) = crt_copysignf(CRT_INFINITY, __c) * __b;
}
else if ((crt_isinf(__a) || crt_isinf(__b)) &&
crt_isfinite(__c) && crt_isfinite(__d))
{
__a = crt_copysignf(crt_isinf(__a) ? 1 : 0, __a);
__b = crt_copysignf(crt_isinf(__b) ? 1 : 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 &&
crt_isfinite(__a) && crt_isfinite(__b))
{
__c = crt_copysignf(crt_isinf(__c) ? 1 : 0, __c);
__d = crt_copysignf(crt_isinf(__d) ? 1 : 0, __d);
COMPLEX_REAL(z) = 0 * (__a * __c + __b * __d);
COMPLEX_IMAGINARY(z) = 0 * (__b * __c - __a * __d);
}
}
return z;
}