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5261 libm should stop using synonyms.h
5298 fabs is 0-sized, confuses dis(1) and others
Reviewed by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
Approved by: Gordon Ross <gwr@nexenta.com>
5262 libm needs to be carefully unifdef'd
5268 libm doesn't need to hide symbols which are already local
Reviewed by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
Reviewed by: Igor Kozhukhov <ikozhukhov@gmail.com>
Reviewed by: Gordon Ross <gwr@nexenta.com>
Approved by: Gordon Ross <gwr@nexenta.com>


   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  23  */
  24 /*
  25  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  26  * Use is subject to license terms.
  27  */
  28 
  29 #pragma weak scalbn = __scalbn
  30 
  31 #include "libm.h"
  32 
  33 static const double
  34         one     = 1.0,
  35         huge    = 1.0e300,
  36         tiny    = 1.0e-300,
  37         twom54  = 5.5511151231257827021181583404541015625e-17;
  38 
  39 #if defined(USE_FPSCALE) || defined(__x86)
  40 static const double two52 = 4503599627370496.0;
  41 #else
  42 /*
  43  * Normalize non-zero subnormal x and return biased exponent of x in [-51,0]
  44  */
  45 static int
  46 ilogb_biased(unsigned *px) {
  47         int s = 52;
  48         unsigned v = px[HIWORD] & ~0x80000000, w = px[LOWORD], t = v;
  49 
  50         if (t)
  51                 s -= 32;
  52         else
  53                 t = w;
  54         if (t & 0xffff0000)
  55                 s -= 16, t >>= 16;
  56         if (t & 0xff00)
  57                 s -= 8, t >>= 8;
  58         if (t & 0xf0)
  59                 s -= 4, t >>= 4;
  60         t <<= 1;
  61         s -= (0xffffaa50 >> t) & 0x3;
  62         if (s < 32) {
  63                 v = (v << s) | w >> (32 - s);
  64                 w <<= s;
  65         } else {
  66                 v = w << (s - 32);
  67                 w = 0;
  68         }
  69         px[HIWORD] = (px[HIWORD] & 0x80000000) | v;
  70         px[LOWORD] = w;
  71         return (1 - s);
  72 }
  73 #endif  /* defined(USE_FPSCALE) */
  74 
  75 double
  76 scalbn(double x, int n) {
  77         int     *px, ix, hx, k;
  78 
  79         px = (int *)&x;
  80         ix = px[HIWORD];
  81         hx = ix & ~0x80000000;
  82         k = hx >> 20;
  83 
  84         if (k == 0x7ff) /* x is inf or NaN */
  85                 return (x * one);
  86 
  87         if (k == 0) {
  88                 if ((hx | px[LOWORD]) == 0 || n == 0)
  89                         return (x);
  90 #if defined(USE_FPSCALE) || defined(__x86)
  91                 x *= two52;
  92                 ix = px[HIWORD];
  93                 k = ((ix & ~0x80000000) >> 20) - 52;
  94 #else
  95                 k = ilogb_biased((unsigned *)px);
  96                 ix = px[HIWORD];
  97 #endif
  98                 /* now k is in the range -51..0 */
  99                 k += n;
 100                 if (k > n)   /* integer overflow occurred */
 101                         k = -100;
 102         } else {
 103                 /* k is in the range 1..1023 */
 104                 k += n;
 105                 if (k < n)   /* integer overflow occurred */
 106                         k = 0x7ff;
 107         }
 108 
 109         if (k > 0x7fe)
 110                 return (huge * ((ix < 0)? -huge : huge));


   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  23  */
  24 /*
  25  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  26  * Use is subject to license terms.
  27  */
  28 
  29 #pragma weak __scalbn = scalbn
  30 
  31 #include "libm.h"
  32 
  33 static const double
  34         one     = 1.0,
  35         huge    = 1.0e300,
  36         tiny    = 1.0e-300,
  37         twom54  = 5.5511151231257827021181583404541015625e-17;
  38 
  39 #if defined(__x86)
  40 static const double two52 = 4503599627370496.0;
  41 #else
  42 /*
  43  * Normalize non-zero subnormal x and return biased exponent of x in [-51,0]
  44  */
  45 static int
  46 ilogb_biased(unsigned *px) {
  47         int s = 52;
  48         unsigned v = px[HIWORD] & ~0x80000000, w = px[LOWORD], t = v;
  49 
  50         if (t)
  51                 s -= 32;
  52         else
  53                 t = w;
  54         if (t & 0xffff0000)
  55                 s -= 16, t >>= 16;
  56         if (t & 0xff00)
  57                 s -= 8, t >>= 8;
  58         if (t & 0xf0)
  59                 s -= 4, t >>= 4;
  60         t <<= 1;
  61         s -= (0xffffaa50 >> t) & 0x3;
  62         if (s < 32) {
  63                 v = (v << s) | w >> (32 - s);
  64                 w <<= s;
  65         } else {
  66                 v = w << (s - 32);
  67                 w = 0;
  68         }
  69         px[HIWORD] = (px[HIWORD] & 0x80000000) | v;
  70         px[LOWORD] = w;
  71         return (1 - s);
  72 }
  73 #endif  /* defined(__x86) */
  74 
  75 double
  76 scalbn(double x, int n) {
  77         int     *px, ix, hx, k;
  78 
  79         px = (int *)&x;
  80         ix = px[HIWORD];
  81         hx = ix & ~0x80000000;
  82         k = hx >> 20;
  83 
  84         if (k == 0x7ff) /* x is inf or NaN */
  85                 return (x * one);
  86 
  87         if (k == 0) {
  88                 if ((hx | px[LOWORD]) == 0 || n == 0)
  89                         return (x);
  90 #if defined(__x86)
  91                 x *= two52;
  92                 ix = px[HIWORD];
  93                 k = ((ix & ~0x80000000) >> 20) - 52;
  94 #else
  95                 k = ilogb_biased((unsigned *)px);
  96                 ix = px[HIWORD];
  97 #endif
  98                 /* now k is in the range -51..0 */
  99                 k += n;
 100                 if (k > n)   /* integer overflow occurred */
 101                         k = -100;
 102         } else {
 103                 /* k is in the range 1..1023 */
 104                 k += n;
 105                 if (k < n)   /* integer overflow occurred */
 106                         k = 0x7ff;
 107         }
 108 
 109         if (k > 0x7fe)
 110                 return (huge * ((ix < 0)? -huge : huge));