LXR linux/arch/mips/math-emu/dp

   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 * http://www.algor.co.uk
   8 *
   9 * ########################################################################
  10 *
  11 *  This program is free software; you can distribute it and/or modify it
  12 *  under the terms of the GNU General Public License (Version 2) as
  13 *  published by the Free Software Foundation.
  14 *
  15 *  This program is distributed in the hope it will be useful, but WITHOUT
  16 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  17 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  18 *  for more details.
  19 *
  20 *  You should have received a copy of the GNU General Public License along
  21 *  with this program; if not, write to the Free Software Foundation, Inc.,
  22 *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  23 *
  24 * ########################################################################
  25 */
  26
  27
  28#include "ieee754dp.h"
  29
  30int ieee754dp_finite(ieee754dp x)
  31{
  32        return DPBEXP(x) != DP_EMAX + 1 + DP_EBIAS;
  33}
  34
  35ieee754dp ieee754dp_copysign(ieee754dp x, ieee754dp y)
  36{
  37        CLEARCX;
  38        DPSIGN(x) = DPSIGN(y);
  39        return x;
  40}
  41
  42
  43ieee754dp ieee754dp_neg(ieee754dp x)
  44{
  45        COMPXDP;
  46
  47        EXPLODEXDP;
  48        CLEARCX;
  49        FLUSHXDP;
  50
  51        /*
  52         * Invert the sign ALWAYS to prevent an endless recursion on
  53         * pow() in libc.
  54         */
  55        /* quick fix up */
  56        DPSIGN(x) ^= 1;
  57
  58        if (xc == IEEE754_CLASS_SNAN) {
  59                ieee754dp y = ieee754dp_indef();
  60                SETCX(IEEE754_INVALID_OPERATION);
  61                DPSIGN(y) = DPSIGN(x);
  62                return ieee754dp_nanxcpt(y, "neg");
  63        }
  64
  65        if (ieee754dp_isnan(x)) /* but not infinity */
  66                return ieee754dp_nanxcpt(x, "neg", x);
  67        return x;
  68}
  69
  70
  71ieee754dp ieee754dp_abs(ieee754dp x)
  72{
  73        COMPXDP;
  74
  75        EXPLODEXDP;
  76        CLEARCX;
  77        FLUSHXDP;
  78
  79        if (xc == IEEE754_CLASS_SNAN) {
  80                SETCX(IEEE754_INVALID_OPERATION);
  81                return ieee754dp_nanxcpt(ieee754dp_indef(), "neg");
  82        }
  83
  84        if (ieee754dp_isnan(x)) /* but not infinity */
  85                return ieee754dp_nanxcpt(x, "abs", x);
  86
  87        /* quick fix up */
  88        DPSIGN(x) = 0;
  89        return x;
  90}
  91