gdtoa/FreeBSD/gdtoa-hexnan.c

   1 /****************************************************************
   2
   3 The author of this software is David M. Gay.
   4
   5 Copyright (C) 2000 by Lucent Technologies
   6 All Rights Reserved
   7
   8 Permission to use, copy, modify, and distribute this software and
   9 its documentation for any purpose and without fee is hereby
  10 granted, provided that the above copyright notice appear in all
  11 copies and that both that the copyright notice and this
  12 permission notice and warranty disclaimer appear in supporting
  13 documentation, and that the name of Lucent or any of its entities
  14 not be used in advertising or publicity pertaining to
  15 distribution of the software without specific, written prior
  16 permission.
  17
  18 LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  19 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
  20 IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
  21 SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  22 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
  23 IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
  24 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
  25 THIS SOFTWARE.
  26
  27 ****************************************************************/
  28
  29 /* Please send bug reports to David M. Gay (dmg at acm dot org,
  30  * with " at " changed at "@" and " dot " changed to ".").      */
  31
  32 #include "gdtoaimp.h"
  33 #include <fpmath.h>
  34
  35 #ifndef __APPLE__
  36  static void
  37 #ifdef KR_headers
  38 L_shift(x, x1, i) ULong *x; ULong *x1; int i;
  39 #else
  40 L_shift(ULong *x, ULong *x1, int i)
  41 #endif
  42 {
  43         int j;
  44
  45         i = 8 - i;
  46         i <<= 2;
  47         j = ULbits - i;
  48         do {
  49                 *x |= x[1] << j;
  50                 x[1] >>= i;
  51                 } while(++x < x1);
  52         }
  53 #endif /* !__APPLE__ */
  54
  55  int
  56 #ifdef KR_headers
  57 hexnan(sp, fpi, x0)
  58         CONST char **sp; CONST FPI *fpi; ULong *x0;
  59 #else
  60 hexnan( CONST char **sp, CONST FPI *fpi, ULong *x0)
  61 #endif
  62 {
  63 #ifdef __APPLE__
  64         int nbits, len;
  65         char *cp;
  66 #else /* !__APPLE__ */
  67         ULong c, h, *x, *x1, *xe;
  68 #endif /* __APPLE__ */
  69         CONST char *s;
  70 #ifndef __APPLE__
  71         int havedig, hd0, i, nbits;
  72 #endif /* !__APPLE__ */
  73
  74 #ifdef __APPLE__
  75         if (sp == NULL || *sp == NULL || **sp != '(')
  76                 return STRTOG_NaN;
  77 #else /* !__APPLE__ */
  78         if (!hexdig['0'])
  79                 hexdig_init_D2A();
  80         nbits = fpi->nbits;
  81         x = x0 + (nbits >> kshift);
  82         if (nbits & kmask)
  83                 x++;
  84         *--x = 0;
  85         x1 = xe = x;
  86         havedig = hd0 = i = 0;
  87 #endif /* __APPLE__ */
  88         s = *sp;
  89 #ifdef __APPLE__
  90         if ((cp = strchr(s + 1, ')')) == NULL) {
  91                 return STRTOG_NaN;
  92                 }
  93         else {
  94                 len = cp - (s + 1);
  95                 cp = alloca(len + 1);
  96                 if (!cp)
  97 #else /* !__APPLE__ */
  98         /* allow optional initial 0x or 0X */
  99         while((c = *(CONST unsigned char*)(s+1)) && c <= ' ')
 100                 ++s;
 101         if (s[1] == '0' && (s[2] == 'x' || s[2] == 'X')
 102          && *(CONST unsigned char*)(s+3) > ' ')
 103                 s += 2;
 104         while((c = *(CONST unsigned char*)++s)) {
 105                 if (!(h = hexdig[c])) {
 106                         if (c <= ' ') {
 107                                 if (hd0 < havedig) {
 108                                         if (x < x1 && i < 8)
 109                                                 L_shift(x, x1, i);
 110                                         if (x <= x0) {
 111                                                 i = 8;
 112                                                 continue;
 113                                                 }
 114                                         hd0 = havedig;
 115                                         *--x = 0;
 116                                         x1 = x;
 117                                         i = 0;
 118                                         }
 119                                 while(*(CONST unsigned char*)(s+1) <= ' ')
 120                                         ++s;
 121                                 if (s[1] == '0' && (s[2] == 'x' || s[2] == 'X')
 122                                  && *(CONST unsigned char*)(s+3) > ' ')
 123                                         s += 2;
 124                                 continue;
 125                                 }
 126                         if (/*(*/ c == ')' && havedig) {
 127                                 *sp = s + 1;
 128                                 break;
 129                                 }
 130 #ifndef GDTOA_NON_PEDANTIC_NANCHECK
 131                         do {
 132                                 if (/*(*/ c == ')') {
 133                                         *sp = s + 1;
 134                                         break;
 135                                         }
 136                                 } while((c = *++s));
 137 #endif
 138 #endif /* __APPLE__ */
 139                         return STRTOG_NaN;
 140 #ifdef __APPLE__
 141                 strlcpy(cp, s + 1, len + 1);
 142                 *sp += len + 2;
 143 #else /* !__APPLE__ */
 144                         }
 145                 havedig++;
 146                 if (++i > 8) {
 147                         if (x <= x0)
 148                                 continue;
 149                         i = 1;
 150                         *--x = 0;
 151                         }
 152                 *x = (*x << 4) | (h & 0xf);
 153 #endif /* __APPLE__ */
 154                 }
 155 #ifdef __APPLE__
 156         nbits = fpi->nbits;
 157         /* a hack */
 158         if (nbits == 52) {      /* double */
 159                 union IEEEd2bits u;
 160                 u.d = nan(cp);
 161                 x0[1] = u.bits.manh;
 162                 x0[0] = u.bits.manl;
 163 #else /* !__APPLE__ */
 164         if (!havedig)
 165                 return STRTOG_NaN;
 166         if (x < x1 && i < 8)
 167                 L_shift(x, x1, i);
 168         if (x > x0) {
 169                 x1 = x0;
 170                 do *x1++ = *x++;
 171                         while(x <= xe);
 172                 do *x1++ = 0;
 173                         while(x1 <= xe);
 174 #endif /* __APPLE__ */
 175                 }
 176 #ifdef __APPLE__
 177         else if (nbits < 52) {  /* float */
 178                 union IEEEf2bits u;
 179                 u.f = nanf(cp);
 180                 x0[0] = u.bits.man;
 181 #else /* !__APPLE__ */
 182         else {
 183                 /* truncate high-order word if necessary */
 184                 if ( (i = nbits & (ULbits-1)) !=0)
 185                         *xe &= ((ULong)0xffffffff) >> (ULbits - i);
 186 #endif /* __APPLE__ */
 187                 }
 188 #ifdef __APPLE__
 189         else {                  /* long double */
 190                 union IEEEl2bits u;
 191                 u.e = nanl(cp);
 192 #if defined(__i386__) || defined(__x86_64__) || defined(__arm__) || defined(__arm64__)
 193                 x0[1] = (ULong)u.bits.manh;
 194                 x0[0] = (ULong)u.bits.manl;
 195 #else
 196 #error unsupported architecture
 197 #endif
 198 #else /* !__APPLE__ */
 199         for(x1 = xe;; --x1) {
 200                 if (*x1 != 0)
 201                         break;
 202                 if (x1 == x0) {
 203                         *x1 = 1;
 204                         break;
 205                         }
 206 #endif /* __APPLE__ */
 207                 }
 208         return STRTOG_NaNbits;
 209         }