1 /*===-- divsc3.c - Implement __divsc3 -------------------------------------===
2  *
3  *                     The LLVM Compiler Infrastructure
4  *
5  * This file is dual licensed under the MIT and the University of Illinois Open
6  * Source Licenses. See LICENSE.TXT for details.
7  *
8  * ===----------------------------------------------------------------------===
9  *
10  * This file implements __divsc3 for the compiler_rt library.
11  *
12  *===----------------------------------------------------------------------===
13  */
14 
15 #include "int_lib.h"
16 #include "int_math.h"
17 
18 /* Returns: the quotient of (a + ib) / (c + id) */
19 
20 COMPILER_RT_ABI float _Complex
__divsc3(float __a,float __b,float __c,float __d)21 __divsc3(float __a, float __b, float __c, float __d)
22 {
23     int __ilogbw = 0;
24     float __logbw = crt_logbf(crt_fmaxf(crt_fabsf(__c), crt_fabsf(__d)));
25     if (crt_isfinite(__logbw))
26     {
27         __ilogbw = (int)__logbw;
28         __c = crt_scalbnf(__c, -__ilogbw);
29         __d = crt_scalbnf(__d, -__ilogbw);
30     }
31     float __denom = __c * __c + __d * __d;
32     float _Complex z;
33     __real__ z = crt_scalbnf((__a * __c + __b * __d) / __denom, -__ilogbw);
34     __imag__ z = crt_scalbnf((__b * __c - __a * __d) / __denom, -__ilogbw);
35     if (crt_isnan(__real__ z) && crt_isnan(__imag__ z))
36     {
37         if ((__denom == 0) && (!crt_isnan(__a) || !crt_isnan(__b)))
38         {
39             __real__ z = crt_copysignf(CRT_INFINITY, __c) * __a;
40             __imag__ z = crt_copysignf(CRT_INFINITY, __c) * __b;
41         }
42         else if ((crt_isinf(__a) || crt_isinf(__b)) &&
43                  crt_isfinite(__c) && crt_isfinite(__d))
44         {
45             __a = crt_copysignf(crt_isinf(__a) ? 1 : 0, __a);
46             __b = crt_copysignf(crt_isinf(__b) ? 1 : 0, __b);
47             __real__ z = CRT_INFINITY * (__a * __c + __b * __d);
48             __imag__ z = CRT_INFINITY * (__b * __c - __a * __d);
49         }
50         else if (crt_isinf(__logbw) && __logbw > 0 &&
51                  crt_isfinite(__a) && crt_isfinite(__b))
52         {
53             __c = crt_copysignf(crt_isinf(__c) ? 1 : 0, __c);
54             __d = crt_copysignf(crt_isinf(__d) ? 1 : 0, __d);
55             __real__ z = 0 * (__a * __c + __b * __d);
56             __imag__ z = 0 * (__b * __c - __a * __d);
57         }
58     }
59     return z;
60 }
61