lib/mulxc3.c

   1 /* ===-- mulxc3.c - Implement __mulxc3 -------------------------------------===
   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 __mulxc3 for the compiler_rt library.
  11  *
  12  * ===----------------------------------------------------------------------===
  13  */
  14
  15 #if !_ARCH_PPC
  16
  17 #include "int_lib.h"
  18 #include "int_math.h"
  19
  20 /* Returns: the product of a + ib and c + id */
  21
  22 long double _Complex
  23 __mulxc3(long double __a, long double __b, long double __c, long double __d)
  24 {
  25     long double __ac = __a * __c;
  26     long double __bd = __b * __d;
  27     long double __ad = __a * __d;
  28     long double __bc = __b * __c;
  29     long double _Complex z;
  30     __real__ z = __ac - __bd;
  31     __imag__ z = __ad + __bc;
  32     if (crt_isnan(__real__ z) && crt_isnan(__imag__ z))
  33     {
  34         int __recalc = 0;
  35         if (crt_isinf(__a) || crt_isinf(__b))
  36         {
  37             __a = crt_copysignl(crt_isinf(__a) ? 1 : 0, __a);
  38             __b = crt_copysignl(crt_isinf(__b) ? 1 : 0, __b);
  39             if (crt_isnan(__c))
  40                 __c = crt_copysignl(0, __c);
  41             if (crt_isnan(__d))
  42                 __d = crt_copysignl(0, __d);
  43             __recalc = 1;
  44         }
  45         if (crt_isinf(__c) || crt_isinf(__d))
  46         {
  47             __c = crt_copysignl(crt_isinf(__c) ? 1 : 0, __c);
  48             __d = crt_copysignl(crt_isinf(__d) ? 1 : 0, __d);
  49             if (crt_isnan(__a))
  50                 __a = crt_copysignl(0, __a);
  51             if (crt_isnan(__b))
  52                 __b = crt_copysignl(0, __b);
  53             __recalc = 1;
  54         }
  55         if (!__recalc && (crt_isinf(__ac) || crt_isinf(__bd) ||
  56                           crt_isinf(__ad) || crt_isinf(__bc)))
  57         {
  58             if (crt_isnan(__a))
  59                 __a = crt_copysignl(0, __a);
  60             if (crt_isnan(__b))
  61                 __b = crt_copysignl(0, __b);
  62             if (crt_isnan(__c))
  63                 __c = crt_copysignl(0, __c);
  64             if (crt_isnan(__d))
  65                 __d = crt_copysignl(0, __d);
  66             __recalc = 1;
  67         }
  68         if (__recalc)
  69         {
  70             __real__ z = CRT_INFINITY * (__a * __c - __b * __d);
  71             __imag__ z = CRT_INFINITY * (__a * __d + __b * __c);
  72         }
  73     }
  74     return z;
  75 }
  76
  77 #endif