compiler-rt/lib/builtins/mulsc3.c

   1 //===-- mulsc3.c - Implement __mulsc3 -------------------------------------===//
   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 __mulsc3 for the compiler_rt library.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "int_lib.h"
  14 #include "int_math.h"
  15
  16 // Returns: the product of a + ib and c + id
  17
  18 COMPILER_RT_ABI Fcomplex __mulsc3(float __a, float __b, float __c, float __d) {
  19   float __ac = __a * __c;
  20   float __bd = __b * __d;
  21   float __ad = __a * __d;
  22   float __bc = __b * __c;
  23   Fcomplex z;
  24   COMPLEX_REAL(z) = __ac - __bd;
  25   COMPLEX_IMAGINARY(z) = __ad + __bc;
  26   if (crt_isnan(COMPLEX_REAL(z)) && crt_isnan(COMPLEX_IMAGINARY(z))) {
  27     int __recalc = 0;
  28     if (crt_isinf(__a) || crt_isinf(__b)) {
  29       __a = crt_copysignf(crt_isinf(__a) ? 1 : 0, __a);
  30       __b = crt_copysignf(crt_isinf(__b) ? 1 : 0, __b);
  31       if (crt_isnan(__c))
  32         __c = crt_copysignf(0, __c);
  33       if (crt_isnan(__d))
  34         __d = crt_copysignf(0, __d);
  35       __recalc = 1;
  36     }
  37     if (crt_isinf(__c) || crt_isinf(__d)) {
  38       __c = crt_copysignf(crt_isinf(__c) ? 1 : 0, __c);
  39       __d = crt_copysignf(crt_isinf(__d) ? 1 : 0, __d);
  40       if (crt_isnan(__a))
  41         __a = crt_copysignf(0, __a);
  42       if (crt_isnan(__b))
  43         __b = crt_copysignf(0, __b);
  44       __recalc = 1;
  45     }
  46     if (!__recalc && (crt_isinf(__ac) || crt_isinf(__bd) || crt_isinf(__ad) ||
  47                       crt_isinf(__bc))) {
  48       if (crt_isnan(__a))
  49         __a = crt_copysignf(0, __a);
  50       if (crt_isnan(__b))
  51         __b = crt_copysignf(0, __b);
  52       if (crt_isnan(__c))
  53         __c = crt_copysignf(0, __c);
  54       if (crt_isnan(__d))
  55         __d = crt_copysignf(0, __d);
  56       __recalc = 1;
  57     }
  58     if (__recalc) {
  59       COMPLEX_REAL(z) = CRT_INFINITY * (__a * __c - __b * __d);
  60       COMPLEX_IMAGINARY(z) = CRT_INFINITY * (__a * __d + __b * __c);
  61     }
  62   }
  63   return z;
  64 }