gts/rounding.h

   1 /* GTS - Library for the manipulation of triangulated surfaces
   2  * Copyright (C) 1999 Stéphane Popinet
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Library General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 #include "config.h"
  21
  22 #ifdef HAVE_FPU_CONTROL_H
  23 #  include <fpu_control.h>
  24 #  ifdef _FPU_EXTENDED
  25 #   if !defined(__alpha__) || !defined(__GLIBC__)
  26 #    if defined(__arm__)
  27      static fpu_control_t fpu_round_double = _FPU_DEFAULT;
  28 #    else
  29      static fpu_control_t fpu_round_double =
  30        (_FPU_DEFAULT & ~ _FPU_EXTENDED)|_FPU_DOUBLE;
  31 #    endif
  32      static fpu_control_t fpu_init;
  33 #    define FPU_ROUND_DOUBLE  { _FPU_GETCW(fpu_init);\
  34                                 _FPU_SETCW(fpu_round_double); }
  35 #    define FPU_RESTORE       {_FPU_SETCW(fpu_init);}
  36 #   else /* __alpha__ && __GLIBC__ */
  37 #    define FPU_ROUND_DOUBLE
  38 #    define FPU_RESTORE
  39 #   endif /* __alpha__ && __GLIBC__ */
  40 #  else /* not FPU_EXTENDED */
  41 #    define FPU_ROUND_DOUBLE
  42 #    define FPU_RESTORE
  43 #  endif /* not FPU_EXTENDED */
  44 #else /* not HAVE_FPU_CONTROL_H */
  45 #  ifdef __FreeBSD__
  46 #    include <floatingpoint.h>
  47 #    define FPU_ROUND_DOUBLE  (fpsetprec(FP_PD))
  48 #    define FPU_RESTORE       (fpsetprec(FP_PE))
  49 #  else /* not __FreeBSD__ */
  50 #    ifdef WIN32
  51 #      ifdef _MSC_VER
  52 #        include <float.h>
  53          static unsigned int fpu_init;
  54 #        define FPU_ROUND_DOUBLE (fpu_init = _controlfp (0, 0),\
  55                                  _controlfp (_PC_53, MCW_PC))
  56 #        define FPU_RESTORE      (_controlfp (fpu_init, 0xfffff))
  57 #      elif __MINGW32__
  58 #        include <float.h>
  59          static unsigned int fpu_init;
  60 #        define FPU_ROUND_DOUBLE (fpu_init = _controlfp (0, 0),\
  61                                   _controlfp (_PC_53, _MCW_PC))
  62 #        define FPU_RESTORE      (_controlfp (fpu_init, 0xfffff))
  63 #      else /* not _MSC_VER or __MINGW32__ */
  64 #        error "You need MSVC or MinGW for the Win32 version"
  65 #      endif /*  not _MSC_VER or __MINGW32__ */
  66 #    else /* not WIN32 */
  67 #      ifdef __CYGWIN__
  68          typedef unsigned int fpu_control_t __attribute__ ((__mode__ (__HI__)));
  69          static fpu_control_t fpu_round_double = 0x027f;
  70          static fpu_control_t fpu_init;
  71 #        define _FPU_GETCW(cw) __asm__ ("fnstcw %0" : "=m" (*&cw))
  72 #        define _FPU_SETCW(cw) __asm__ ("fldcw %0" : : "m" (*&cw))
  73 #        define FPU_ROUND_DOUBLE  { _FPU_GETCW(fpu_init);\
  74                                     _FPU_SETCW(fpu_round_double); }
  75 #        define FPU_RESTORE       { _FPU_SETCW(fpu_init);}
  76 #      else /* not __CYGWIN__ */
  77 #        ifdef CPP_HAS_WARNING
  78 #          warning "Unknown CPU: assuming default double precision rounding"
  79 #        endif /* CPP_HAS_WARNING */
  80 #        define FPU_ROUND_DOUBLE
  81 #        define FPU_RESTORE
  82 #      endif /* not __CYGWIN__ */
  83 #    endif /* not WIN32 */
  84 #  endif /* not __FreeBSD__ */
  85 #endif /* not HAVE_FPU_CONTROL_H */