libgcc/__negti2.c

   1 /* Extracted from gcc-3.4.1/gcc/config/mips/_tilibi.c */
   2 /* A few TImode functions needed for TFmode emulated arithmetic.
   3    Copyright 2002, 2003 Free Software Foundation, Inc.
   4    Contributed by Alexandre Oliva <aoliva@redhat.com>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 2, or (at your option)
  11 any later version.
  12
  13 GCC is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING.  If not, write to
  20 the Free Software Foundation, 59 Temple Place - Suite 330,
  21 Boston, MA 02111-1307, USA.  */
  22
  23 #include "libgcc.h"
  24
  25 #if defined(__sparc__) || defined(__ppc__)
  26 #define LIBGCC2_WORDS_BIG_ENDIAN
  27 #endif
  28
  29 typedef union
  30 {
  31   struct TIstruct {
  32 #if defined(LIBGCC2_WORDS_BIG_ENDIAN)
  33     DItype high, low;
  34 #else
  35     DItype low, high;
  36 #endif
  37   } s;
  38   TItype ll;
  39 } TIunion;
  40
  41 TItype
  42 __negti2 (TItype u)
  43 {
  44   TIunion w;
  45   TIunion uu;
  46
  47   uu.ll = u;
  48
  49   w.s.low = -uu.s.low;
  50   w.s.high = -uu.s.high - ((UDItype) w.s.low > 0);
  51
  52   return w.ll;
  53 }