arch/mips/math-emu/dp_cmp.c

   1 /* IEEE754 floating point arithmetic
   2  * double precision: common utilities
   3  */
   4 /*
   5  * MIPS floating point support
   6  * Copyright (C) 1994-2000 Algorithmics Ltd.
   7  *
   8  *  This program is free software; you can distribute it and/or modify it
   9  *  under the terms of the GNU General Public License (Version 2) as
  10  *  published by the Free Software Foundation.
  11  *
  12  *  This program is distributed in the hope it will be useful, but WITHOUT
  13  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15  *  for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License along
  18  *  with this program; if not, write to the Free Software Foundation, Inc.,
  19  *  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA.
  20  */
  21
  22 #include "ieee754dp.h"
  23
  24 int ieee754dp_cmp(union ieee754dp x, union ieee754dp y, int cmp, int sig)
  25 {
  26         s64 vx;
  27         s64 vy;
  28
  29         COMPXDP;
  30         COMPYDP;
  31
  32         EXPLODEXDP;
  33         EXPLODEYDP;
  34         FLUSHXDP;
  35         FLUSHYDP;
  36         ieee754_clearcx();      /* Even clear inexact flag here */
  37
  38         if (ieee754dp_isnan(x) || ieee754dp_isnan(y)) {
  39                 if (sig || xc == IEEE754_CLASS_SNAN || yc == IEEE754_CLASS_SNAN)
  40                         ieee754_setcx(IEEE754_INVALID_OPERATION);
  41                 if (cmp & IEEE754_CUN)
  42                         return 1;
  43                 if (cmp & (IEEE754_CLT | IEEE754_CGT)) {
  44                         if (sig && ieee754_setandtestcx(IEEE754_INVALID_OPERATION))
  45                                 return 0;
  46                 }
  47                 return 0;
  48         } else {
  49                 vx = x.bits;
  50                 vy = y.bits;
  51
  52                 if (vx < 0)
  53                         vx = -vx ^ DP_SIGN_BIT;
  54                 if (vy < 0)
  55                         vy = -vy ^ DP_SIGN_BIT;
  56
  57                 if (vx < vy)
  58                         return (cmp & IEEE754_CLT) != 0;
  59                 else if (vx == vy)
  60                         return (cmp & IEEE754_CEQ) != 0;
  61                 else
  62                         return (cmp & IEEE754_CGT) != 0;
  63         }
  64 }