1 /*===-- divtc3.c - Implement __divtc3 -------------------------------------===
3 * The LLVM Compiler Infrastructure
5 * This file is dual licensed under the MIT and the University of Illinois Open
6 * Source Licenses. See LICENSE.TXT for details.
8 * ===----------------------------------------------------------------------===
10 * This file implements __divtc3 for the compiler_rt library.
12 *===----------------------------------------------------------------------===
18 /* Returns: the quotient of (a + ib) / (c + id) */
20 COMPILER_RT_ABI Lcomplex
21 __divtc3(long double __a, long double __b, long double __c, long double __d)
24 long double __logbw = crt_logbl(crt_fmaxl(crt_fabsl(__c), crt_fabsl(__d)));
25 if (crt_isfinite(__logbw))
27 __ilogbw = (int)__logbw;
28 __c = crt_scalbnl(__c, -__ilogbw);
29 __d = crt_scalbnl(__d, -__ilogbw);
31 long double __denom = __c * __c + __d * __d;
33 COMPLEX_REAL(z) = crt_scalbnl((__a * __c + __b * __d) / __denom, -__ilogbw);
34 COMPLEX_IMAGINARY(z) = crt_scalbnl((__b * __c - __a * __d) / __denom, -__ilogbw);
35 if (crt_isnan(COMPLEX_REAL(z)) && crt_isnan(COMPLEX_IMAGINARY(z)))
37 if ((__denom == 0.0) && (!crt_isnan(__a) || !crt_isnan(__b)))
39 COMPLEX_REAL(z) = crt_copysignl(CRT_INFINITY, __c) * __a;
40 COMPLEX_IMAGINARY(z) = crt_copysignl(CRT_INFINITY, __c) * __b;
42 else if ((crt_isinf(__a) || crt_isinf(__b)) &&
43 crt_isfinite(__c) && crt_isfinite(__d))
45 __a = crt_copysignl(crt_isinf(__a) ? 1.0 : 0.0, __a);
46 __b = crt_copysignl(crt_isinf(__b) ? 1.0 : 0.0, __b);
47 COMPLEX_REAL(z) = CRT_INFINITY * (__a * __c + __b * __d);
48 COMPLEX_IMAGINARY(z) = CRT_INFINITY * (__b * __c - __a * __d);
50 else if (crt_isinf(__logbw) && __logbw > 0.0 &&
51 crt_isfinite(__a) && crt_isfinite(__b))
53 __c = crt_copysignl(crt_isinf(__c) ? 1.0 : 0.0, __c);
54 __d = crt_copysignl(crt_isinf(__d) ? 1.0 : 0.0, __d);
55 COMPLEX_REAL(z) = 0.0 * (__a * __c + __b * __d);
56 COMPLEX_IMAGINARY(z) = 0.0 * (__b * __c - __a * __d);