reactos/lib/msvcrt/float/cntrlfp.c

   1 /* Copyright (C) 1995 DJ Delorie, see COPYING.DJ for details */
   2
   3 #include <msvcrt/float.h>
   4
   5 unsigned int _controlfp(unsigned int unNew, unsigned int unMask)
   6 {
   7   return _control87(unNew,unMask);
   8 }
   9
  10 unsigned int _control87(unsigned int unNew, unsigned int unMask)
  11 {
  12 register unsigned int __res;
  13 #ifdef __GNUC__
  14 __asm__ __volatile__ (
  15         "pushl  %%eax \n\t"             /* make room on stack */
  16         "fstcw  (%%esp) \n\t"
  17         "fwait \n\t"
  18         "popl   %%eax \n\t"
  19         "andl   $0xffff, %%eax  \n\t"   /* OK;  we have the old value ready */
  20
  21         "movl   %1, %%ecx \n\t"
  22         "notl   %%ecx \n\t"
  23         "andl   %%eax, %%ecx \n\t"      /* the bits we want to keep */
  24
  25         "movl   %2, %%edx \n\t"
  26         "andl   %1, %%edx \n\t" /* the bits we want to change */
  27
  28         "orl    %%ecx, %%edx\n\t"               /* the new value */
  29         "pushl  %%edx \n\t"
  30         "fldcw  (%%esp) \n\t"
  31         "popl   %%edx \n\t"
  32
  33         :"=r" (__res):"r" (unNew),"r" (unMask): "ax", "dx", "cx");
  34 #else
  35 #endif /*__GNUC__*/
  36         return __res;
  37 }