usr/src/lib/libc/port/fp/__flt_rounds.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 2008 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 /*
  30  * These functions return the prevailing rounding mode per ANSI C spec:
  31  *       0:     toward zero
  32  *       1:     to nearest                      <<< default
  33  *       2:     toward positive infinity
  34  *       3:     toward negative infinity
  35  *      -1:     indeterminable                  <<< never returned
  36  */
  37
  38 #include "lint.h"
  39 #include <sys/types.h>
  40 #include <floatingpoint.h>
  41 #include "libc.h"
  42
  43 #if defined(__sparc)
  44
  45 int
  46 __flt_rounds(void)
  47 {
  48         switch (_QgetRD()) {
  49         case fp_tozero:
  50                 return (0);
  51
  52         case fp_positive:
  53                 return (2);
  54
  55         case fp_negative:
  56                 return (3);
  57         }
  58         return (1);
  59 }
  60
  61 #elif defined(__i386) || defined(__amd64)
  62
  63 int
  64 __fltrounds(void)
  65 {
  66         switch (__xgetRD()) {
  67         case fp_tozero:
  68                 return (0);
  69
  70         case fp_positive:
  71                 return (2);
  72
  73         case fp_negative:
  74                 return (3);
  75         }
  76         return (1);
  77 }
  78
  79 #else
  80 #error Unknown architecture
  81 #endif