| //===-- divdc3.c - Implement __divdc3 -------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements __divdc3 for the compiler_rt library. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #define DOUBLE_PRECISION |
| #include "fp_lib.h" |
| #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 = __compiler_rt_logb(__compiler_rt_fmax(crt_fabs(__c), |
| crt_fabs(__d))); |
| if (crt_isfinite(__logbw)) { |
| __ilogbw = (int)__logbw; |
| __c = __compiler_rt_scalbn(__c, -__ilogbw); |
| __d = __compiler_rt_scalbn(__d, -__ilogbw); |
| } |
| double __denom = __c * __c + __d * __d; |
| Dcomplex z; |
| COMPLEX_REAL(z) = |
| __compiler_rt_scalbn((__a * __c + __b * __d) / __denom, -__ilogbw); |
| COMPLEX_IMAGINARY(z) = |
| __compiler_rt_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; |
| } |
