xref: /freebsd/contrib/llvm-project/compiler-rt/lib/builtins/divtc3.c (revision b64c5a0ace59af62eff52bfe110a521dc73c937b)
1 //===-- divtc3.c - Implement __divtc3 -------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements __divtc3 for the compiler_rt library.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #define QUAD_PRECISION
14 #include "fp_lib.h"
15 
16 #if defined(CRT_HAS_128BIT) && defined(CRT_HAS_F128)
17 
18 // Returns: the quotient of (a + ib) / (c + id)
19 
20 COMPILER_RT_ABI Qcomplex __divtc3(fp_t __a, fp_t __b, fp_t __c, fp_t __d) {
21   int __ilogbw = 0;
22   fp_t __logbw = __compiler_rt_logbtf(
23       __compiler_rt_fmaxtf(crt_fabstf(__c), crt_fabstf(__d)));
24   if (crt_isfinite(__logbw)) {
25     __ilogbw = (int)__logbw;
26     __c = __compiler_rt_scalbntf(__c, -__ilogbw);
27     __d = __compiler_rt_scalbntf(__d, -__ilogbw);
28   }
29   fp_t __denom = __c * __c + __d * __d;
30   Qcomplex z;
31   COMPLEXTF_REAL(z) =
32       __compiler_rt_scalbntf((__a * __c + __b * __d) / __denom, -__ilogbw);
33   COMPLEXTF_IMAGINARY(z) =
34       __compiler_rt_scalbntf((__b * __c - __a * __d) / __denom, -__ilogbw);
35   if (crt_isnan(COMPLEXTF_REAL(z)) && crt_isnan(COMPLEXTF_IMAGINARY(z))) {
36     if ((__denom == 0.0) && (!crt_isnan(__a) || !crt_isnan(__b))) {
37       COMPLEXTF_REAL(z) = crt_copysigntf(CRT_INFINITY, __c) * __a;
38       COMPLEXTF_IMAGINARY(z) = crt_copysigntf(CRT_INFINITY, __c) * __b;
39     } else if ((crt_isinf(__a) || crt_isinf(__b)) && crt_isfinite(__c) &&
40                crt_isfinite(__d)) {
41       __a = crt_copysigntf(crt_isinf(__a) ? (fp_t)1.0 : (fp_t)0.0, __a);
42       __b = crt_copysigntf(crt_isinf(__b) ? (fp_t)1.0 : (fp_t)0.0, __b);
43       COMPLEXTF_REAL(z) = CRT_INFINITY * (__a * __c + __b * __d);
44       COMPLEXTF_IMAGINARY(z) = CRT_INFINITY * (__b * __c - __a * __d);
45     } else if (crt_isinf(__logbw) && __logbw > 0.0 && crt_isfinite(__a) &&
46                crt_isfinite(__b)) {
47       __c = crt_copysigntf(crt_isinf(__c) ? (fp_t)1.0 : (fp_t)0.0, __c);
48       __d = crt_copysigntf(crt_isinf(__d) ? (fp_t)1.0 : (fp_t)0.0, __d);
49       COMPLEXTF_REAL(z) = 0.0 * (__a * __c + __b * __d);
50       COMPLEXTF_IMAGINARY(z) = 0.0 * (__b * __c - __a * __d);
51     }
52   }
53   return z;
54 }
55 
56 #endif
57