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5261 libm should stop using synonyms.h
    
      
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          --- old/usr/src/lib/libm/common/m9x/scalbln.c
          +++ new/usr/src/lib/libm/common/m9x/scalbln.c
   1    1  /*
   2    2   * CDDL HEADER START
   3    3   *
   4    4   * The contents of this file are subject to the terms of the
   5    5   * Common Development and Distribution License (the "License").
   6    6   * You may not use this file except in compliance with the License.
   7    7   *
   8    8   * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9    9   * or http://www.opensolaris.org/os/licensing.
  10   10   * See the License for the specific language governing permissions
  11   11   * and limitations under the License.
  12   12   *
  13   13   * When distributing Covered Code, include this CDDL HEADER in each
  14   14   * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15   15   * If applicable, add the following below this CDDL HEADER, with the
  16   16   * fields enclosed by brackets "[]" replaced with your own identifying
  17   17   * information: Portions Copyright [yyyy] [name of copyright owner]
  18   18   *
  19   19   * CDDL HEADER END
  
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  20   20   */
  21   21  
  22   22  /*
  23   23   * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  24   24   */
  25   25  /*
  26   26   * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  27   27   * Use is subject to license terms.
  28   28   */
  29   29  
  30      -#pragma weak scalbln = __scalbln
       30 +#pragma weak __scalbln = scalbln
  31   31  
  32   32  #include "libm.h"
  33   33  #include <float.h>              /* DBL_MAX, DBL_MIN */
  34   34  
  35   35  static const double twom54 = 5.5511151231257827021181583404541015625e-17;
  36   36  #if defined(__x86)
  37   37  static const double two52 = 4503599627370496.0;
  38   38  #else
  39   39  /*
  40   40   * Normalize non-zero subnormal x and return biased exponent of x in [-51,0]
  41   41   */
  42   42  static int
  43   43  ilogb_biased(unsigned *px) {
  44   44          int s = 52;
  45   45          unsigned v = px[HIWORD] & ~0x80000000, w = px[LOWORD], t = v;
  46   46  
  47   47          if (t)
  48   48                  s -= 32;
  49   49          else
  50   50                  t = w;
  51   51          if (t & 0xffff0000)
  52   52                  s -= 16, t >>= 16;
  53   53          if (t & 0xff00)
  54   54                  s -= 8, t >>= 8;
  55   55          if (t & 0xf0)
  56   56                  s -= 4, t >>= 4;
  57   57          t <<= 1;
  58   58          s -= (0xffffaa50 >> t) & 0x3;
  59   59          if (s < 32) {
  60   60                  v = (v << s) | w >> (32 - s);
  61   61                  w <<= s;
  62   62          } else {
  63   63                  v = w << (s - 32);
  64   64                  w = 0;
  65   65          }
  66   66          px[HIWORD] = (px[HIWORD] & 0x80000000) | v;
  67   67          px[LOWORD] = w;
  68   68          return (1 - s);
  69   69  }
  70   70  #endif  /* defined(__x86) */
  71   71  
  72   72  double
  73   73  scalbln(double x, long n) {
  74   74          int *px = (int *) &x, ix, k;
  75   75  
  76   76          ix = px[HIWORD] & ~0x80000000;
  77   77          k = ix >> 20;
  78   78          if (k == 0x7ff)
  79   79  #if defined(FPADD_TRAPS_INCOMPLETE_ON_NAN)
  80   80                  return ((px[HIWORD] & 0x80000) != 0 ? x : x + x);
  81   81                  /* assumes sparc-like QNaN */
  82   82  #else
  83   83                  return (x + x);
  84   84  #endif
  85   85          if ((px[LOWORD] | ix) == 0 || n == 0)
  86   86                  return (x);
  87   87          if (k == 0) {
  88   88  #if defined(__x86)
  89   89                  x *= two52;
  90   90                  k = ((px[HIWORD] & ~0x80000000) >> 20) - 52;
  91   91  #else
  92   92                  k = ilogb_biased((unsigned *) px);
  93   93  #endif
  94   94          }
  95   95          k += (int) n;
  96   96          if (n > 5000 || k > 0x7fe)
  97   97                  return (DBL_MAX * copysign(DBL_MAX, x));
  98   98          if (n < -5000 || k <= -54)
  99   99                  return (DBL_MIN * copysign(DBL_MIN, x));
 100  100          if (k > 0) {
 101  101                  px[HIWORD] = (px[HIWORD] & ~0x7ff00000) | (k << 20);
 102  102                  return (x);
 103  103          }
 104  104          k += 54;
 105  105          px[HIWORD] = (px[HIWORD] & ~0x7ff00000) | (k << 20);
 106  106          return (x * twom54);
 107  107  }
  
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