usr/src/lib/libm/common/m9x/fminl.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   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 /*
  23  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  24  */
  25 /*
  26  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  27  * Use is subject to license terms.
  28  */
  29
  30 #pragma weak fminl = __fminl
  31
  32 #include "libm.h"       /* for islessequal macro */
  33
  34 long double
  35 __fminl(long double x, long double y) {
  36         union {
  37 #if defined(__sparc)
  38                 unsigned i[4];
  39 #elif defined(__x86)
  40                 unsigned i[3];
  41 #else
  42 #error Unknown architecture
  43 #endif
  44                 long double ld;
  45         } xx, yy;
  46         unsigned s;
  47
  48         /* if y is nan, replace it by x */
  49         if (y != y)
  50                 y = x;
  51
  52         /* if x is nan, replace it by y */
  53         if (x != x)
  54                 x = y;
  55
  56         /* At this point, x and y are either both numeric, or both NaN */
  57         if (!isnan(x) && !islessequal(x, y))
  58                 x = y;
  59
  60         /*
  61          * set the sign of the result if either x or y has its sign set
  62          */
  63         xx.ld = x;
  64         yy.ld = y;
  65 #if defined(__sparc)
  66         s = (xx.i[0] | yy.i[0]) & 0x80000000;
  67         xx.i[0] |= s;
  68 #elif defined(__x86)
  69         s = (xx.i[2] | yy.i[2]) & 0x8000;
  70         xx.i[2] |= s;
  71 #else
  72 #error Unknown architecture
  73 #endif
  74
  75         return (xx.ld);
  76 }