reactos/lib/sdk/crt/math/i386/floorf.S

   1 /*
   2  * Written by J.T. Conklin <jtc@netbsd.org>.
   3  * Public domain.
   4  *
   5  * Changes for long double by Ulrich Drepper <drepper@cygnus.com>
   6  *
   7  * Removed header file dependency for use in libmingwex.a by
   8  *   Danny Smith <dannysmith@users.sourceforge.net>
   9  */
  10
  11 #include <asm.inc>
  12
  13 .code
  14 .align 4
  15
  16 PUBLIC _floorf
  17 _floorf:
  18
  19         fld dword ptr [esp + 4]
  20         sub esp, 8
  21
  22         fstcw [esp + 4]         /* store fpu control word */
  23
  24         /* We use here %edx although only the low 1 bits are defined.
  25            But none of the operations should care and they are faster
  26            than the 16 bit operations.  */
  27         mov edx, [esp + 4]
  28         or edx, HEX(0400)               /* round towards -oo */
  29         and edx, HEX(0f7ff)
  30         mov [esp], edx
  31         fldcw [esp]                     /* load modified control word */
  32
  33         frndint                         /* round */
  34
  35         fldcw [esp + 4]                 /* restore original control word */
  36
  37         add esp, 8
  38         ret
  39
  40 END