arch/mips/math-emu/dp_simple.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  * ########################################################################
   9  *
  10  *  This program is free software; you can distribute it and/or modify it
  11  *  under the terms of the GNU General Public License (Version 2) as
  12  *  published by the Free Software Foundation.
  13  *
  14  *  This program is distributed in the hope it will be useful, but WITHOUT
  15  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  17  *  for more details.
  18  *
  19  *  You should have received a copy of the GNU General Public License along
  20  *  with this program; if not, write to the Free Software Foundation, Inc.,
  21  *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  22  *
  23  * ########################################################################
  24  */
  25
  26
  27 #include "ieee754dp.h"
  28
  29 int ieee754dp_finite(ieee754dp x)
  30 {
  31         return DPBEXP(x) != DP_EMAX + 1 + DP_EBIAS;
  32 }
  33
  34 ieee754dp ieee754dp_copysign(ieee754dp x, ieee754dp y)
  35 {
  36         CLEARCX;
  37         DPSIGN(x) = DPSIGN(y);
  38         return x;
  39 }
  40
  41
  42 ieee754dp ieee754dp_neg(ieee754dp x)
  43 {
  44         COMPXDP;
  45
  46         EXPLODEXDP;
  47         CLEARCX;
  48         FLUSHXDP;
  49
  50         /*
  51          * Invert the sign ALWAYS to prevent an endless recursion on
  52          * pow() in libc.
  53          */
  54         /* quick fix up */
  55         DPSIGN(x) ^= 1;
  56
  57         if (xc == IEEE754_CLASS_SNAN) {
  58                 ieee754dp y = ieee754dp_indef();
  59                 SETCX(IEEE754_INVALID_OPERATION);
  60                 DPSIGN(y) = DPSIGN(x);
  61                 return ieee754dp_nanxcpt(y, "neg");
  62         }
  63
  64         return x;
  65 }
  66
  67
  68 ieee754dp ieee754dp_abs(ieee754dp x)
  69 {
  70         COMPXDP;
  71
  72         EXPLODEXDP;
  73         CLEARCX;
  74         FLUSHXDP;
  75
  76         /* Clear sign ALWAYS, irrespective of NaN */
  77         DPSIGN(x) = 0;
  78
  79         if (xc == IEEE754_CLASS_SNAN) {
  80                 SETCX(IEEE754_INVALID_OPERATION);
  81                 return ieee754dp_nanxcpt(ieee754dp_indef(), "abs");
  82         }
  83
  84         return x;
  85 }