arch/m68k-all/mlib/fenv.c

   1 /*-
   2  * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  * $FreeBSD: src/lib/msun/arm/fenv.c,v 1.1.20.1 2009/04/15 03:14:26 kensmith Exp $
  27  */
  28
  29 #include <errno.h>
  30 #include <fenv.h>
  31
  32 /*
  33  * Hopefully the system ID byte is immutable, so it's valid to use
  34  * this as a default environment.
  35  */
  36 const fenv_t __fe_dfl_env = { };
  37 static fenv_t fe_env;
  38
  39 /* FIXME: These are just stubs for the moment for soft-float
  40  *        A new implemntation is needed for hard-float support
  41  */
  42
  43 /* Clear the supported exceptions represented by EXCEPTS.  */
  44 int feclearexcept (int __excepts)
  45 {
  46     fe_env.__status_register &= ~__excepts;
  47     return 0;
  48 }
  49
  50 /* Store implementation-defined representation of the exception flags
  51    indicated by EXCEPTS in the object pointed to by FLAGP.  */
  52 int fegetexceptflag (fexcept_t *__flagp, int __excepts)
  53 {
  54     *__flagp = __excepts;
  55     return 0;
  56 }
  57
  58 /* Raise the supported exceptions represented by EXCEPTS.  */
  59 int feraiseexcept (int __excepts)
  60 {
  61     if (__excepts & (FE_UNDERFLOW | FE_OVERFLOW)) {
  62         errno = ERANGE;
  63     } else if (__excepts) {
  64         errno = EDOM;
  65     }
  66     return 0;
  67 }
  68
  69 /* Set complete status for exceptions indicated by EXCEPTS according to
  70    the representation in the object pointed to by FLAGP.  */
  71 int fesetexceptflag(const fexcept_t *flagp, int excepts)
  72 {
  73     fe_env.__status_register &= ~excepts;
  74     return 0;
  75 }
  76
  77 /* Determine which of subset of the exceptions specified by EXCEPTS are
  78    currently set.  */
  79 int fetestexcept (int __excepts)
  80 {
  81     return (fe_env.__status_register & __excepts);
  82 }
  83
  84 /* Store the current floating-point environment in the object pointed
  85    to by ENVP.  */
  86 int fegetenv (fenv_t *envp)
  87 {
  88     *envp = fe_env;
  89     return 0;
  90 }
  91
  92 /* Save the current environment in the object pointed to by ENVP, clear
  93    exception flags and install a non-stop mode (if available) for all
  94    exceptions.  */
  95 int feholdexcept (fenv_t *envp)
  96 {
  97     *envp = fe_env;
  98     errno = 0;
  99     return 0;
 100 }
 101
 102 /* Establish the floating-point environment represented by the object
 103    pointed to by ENVP.  */
 104 int fesetenv(const fenv_t *envp)
 105 {
 106     fe_env = *envp;
 107     return 0;
 108 }
 109
 110 /* Save current exceptions in temporary storage, install environment
 111    represented by object pointed to by ENVP and raise exceptions
 112    according to saved exceptions.  */
 113 int feupdateenv(const fenv_t *envp)
 114 {
 115     int fexcept = fe_env.__status_register;
 116     fesetenv(envp);
 117     feraiseexcept(fexcept);
 118     return 0;
 119 }