lib/libm/i386/s_trunc.S

   1 /*
   2  * Based on code written by J.T. Conklin <jtc@NetBSD.org>.
   3  * Public domain.
   4  *
   5  * $FreeBSD: head/lib/msun/i387/s_trunc.S 217108 2011-01-07 16:13:12Z kib $
   6  */
   7
   8 #include <machine/asm.h>
   9
  10 ENTRY(trunc)
  11         pushl   %ebp
  12         movl    %esp,%ebp
  13         subl    $8,%esp
  14
  15         fstcw   -4(%ebp)                /* store fpu control word */
  16         movw    -4(%ebp),%dx
  17         orw     $0x0c00,%dx             /* round towards -oo */
  18         movw    %dx,-8(%ebp)
  19         fldcw   -8(%ebp)                /* load modfied control word */
  20
  21         fldl    8(%ebp)                 /* round */
  22         frndint
  23
  24         fldcw   -4(%ebp)                /* restore original control word */
  25
  26         leave
  27         ret
  28 END(trunc)
  29
  30         .section .note.GNU-stack,"",%progbits