StdLib/LibC/gdtoa/smisc.c

   1 /* $NetBSD: smisc.c,v 1.2.14.1 2008/04/08 21:10:55 jdc Exp $ */
   2
   3 /****************************************************************
   4
   5 The author of this software is David M. Gay.
   6
   7 Copyright (C) 1998, 1999 by Lucent Technologies
   8 All Rights Reserved
   9
  10 Permission to use, copy, modify, and distribute this software and
  11 its documentation for any purpose and without fee is hereby
  12 granted, provided that the above copyright notice appear in all
  13 copies and that both that the copyright notice and this
  14 permission notice and warranty disclaimer appear in supporting
  15 documentation, and that the name of Lucent or any of its entities
  16 not be used in advertising or publicity pertaining to
  17 distribution of the software without specific, written prior
  18 permission.
  19
  20 LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  21 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
  22 IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
  23 SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  24 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
  25 IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
  26 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
  27 THIS SOFTWARE.
  28
  29 ****************************************************************/
  30
  31 /* Please send bug reports to David M. Gay (dmg at acm dot org,
  32  * with " at " changed at "@" and " dot " changed to ".").  */
  33 #include  <LibConfig.h>
  34
  35 #include "gdtoaimp.h"
  36
  37 #if defined(_MSC_VER)           /* Handle Microsoft VC++ compiler specifics. */
  38 // Disable: warning C4700: uninitialized local variable 'xx' used
  39 #pragma warning ( disable : 4700 )
  40 #endif  /* defined(_MSC_VER) */
  41
  42 Bigint *
  43 s2b
  44 #ifdef KR_headers
  45   (s, nd0, nd, y9) CONST char *s; int nd0, nd; ULong y9;
  46 #else
  47   (CONST char *s, int nd0, int nd, ULong y9)
  48 #endif
  49 {
  50   Bigint *b;
  51   int i, k;
  52   Long x, y;
  53
  54   x = (nd + 8) / 9;
  55   for(k = 0, y = 1; x > y; y <<= 1, k++) ;
  56 #ifdef Pack_32
  57   b = Balloc(k);
  58   if (b == NULL)
  59     return NULL;
  60   b->x[0] = y9;
  61   b->wds = 1;
  62 #else
  63   b = Balloc(k+1);
  64   if (b == NULL)
  65     return NULL;
  66   b->x[0] = y9 & 0xffff;
  67   b->wds = (b->x[1] = y9 >> 16) ? 2 : 1;
  68 #endif
  69
  70   i = 9;
  71   if (9 < nd0) {
  72     s += 9;
  73     do  {
  74       b = multadd(b, 10, *s++ - '0');
  75       if (b == NULL)
  76         return NULL;
  77       } while(++i < nd0);
  78     s++;
  79     }
  80   else
  81     s += 10;
  82   for(; i < nd; i++) {
  83     b = multadd(b, 10, *s++ - '0');
  84     if (b == NULL)
  85       return NULL;
  86     }
  87   return b;
  88   }
  89
  90  double
  91 ratio
  92 #ifdef KR_headers
  93   (a, b) Bigint *a, *b;
  94 #else
  95   (Bigint *a, Bigint *b)
  96 #endif
  97 {
  98   double da, db;
  99   int k, ka, kb;
 100
 101   dval(da) = b2d(a, &ka);
 102   dval(db) = b2d(b, &kb);
 103   k = ka - kb + ULbits*(a->wds - b->wds);
 104 #ifdef IBM
 105   if (k > 0) {
 106     word0(da) += (k >> 2)*Exp_msk1;
 107     if (k &= 3)
 108       dval(da) *= 1 << k;
 109     }
 110   else {
 111     k = -k;
 112     word0(db) += (k >> 2)*Exp_msk1;
 113     if (k &= 3)
 114       dval(db) *= 1 << k;
 115     }
 116 #else
 117   if (k > 0)
 118     word0(da) += k*Exp_msk1;
 119   else {
 120     k = -k;
 121     word0(db) += k*Exp_msk1;
 122     }
 123 #endif
 124   return dval(da) / dval(db);
 125   }
 126
 127 #ifdef INFNAN_CHECK
 128
 129  int
 130 match
 131 #ifdef KR_headers
 132   (sp, t) CONST char **sp, *t;
 133 #else
 134   (CONST char **sp, CONST char *t)
 135 #endif
 136 {
 137   int c, d;
 138   CONST char *s = *sp;
 139
 140   while( (d = *t++) !=0) {
 141     if ((c = *++s) >= 'A' && c <= 'Z')
 142       c += 'a' - 'A';
 143     if (c != d)
 144       return 0;
 145     }
 146   *sp = s + 1;
 147   return 1;
 148   }
 149 #endif /* INFNAN_CHECK */
 150
 151  void
 152 #ifdef KR_headers
 153 copybits(c, n, b) ULong *c; int n; Bigint *b;
 154 #else
 155 copybits(ULong *c, int n, Bigint *b)
 156 #endif
 157 {
 158   ULong *ce, *x, *xe;
 159 #ifdef Pack_16
 160   int nw, nw1;
 161 #endif
 162
 163   ce = c + ((unsigned int)(n-1) >> kshift) + 1;
 164   x = b->x;
 165 #ifdef Pack_32
 166   xe = x + b->wds;
 167   while(x < xe)
 168     *c++ = *x++;
 169 #else
 170   nw = b->wds;
 171   nw1 = nw & 1;
 172   for(xe = x + (nw - nw1); x < xe; x += 2)
 173     Storeinc(c, x[1], x[0]);
 174   if (nw1)
 175     *c++ = *x;
 176 #endif
 177   while(c < ce)
 178     *c++ = 0;
 179   }
 180
 181  ULong
 182 #ifdef KR_headers
 183 any_on(b, k) Bigint *b; int k;
 184 #else
 185 any_on(Bigint *b, int k)
 186 #endif
 187 {
 188   int n, nwds;
 189   ULong *x, *x0, x1, x2;
 190
 191   x = b->x;
 192   nwds = b->wds;
 193   n = (unsigned int)k >> kshift;
 194   if (n > nwds)
 195     n = nwds;
 196   else if (n < nwds && (k &= kmask)) {
 197     x1 = x2 = x[n];
 198     x1 >>= k;
 199     x1 <<= k;
 200     if (x1 != x2)
 201       return 1;
 202     }
 203   x0 = x;
 204   x += n;
 205   while(x > x0)
 206     if (*--x)
 207       return 1;
 208   return 0;
 209   }