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glibc  2.9
fpu_control.h
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00001 /* FPU control word definitions.  Stub version.
00002    Copyright (C) 2000 Free Software Foundation, Inc.
00003    Contributed by Denis Joseph Barrow (djbarrow@de.ibm.com) and
00004    Martin Schwidefsky (schwidefsky@de.ibm.com).
00005    This file is part of the GNU C Library.
00006 
00007    The GNU C Library is free software; you can redistribute it and/or
00008    modify it under the terms of the GNU Lesser General Public
00009    License as published by the Free Software Foundation; either
00010    version 2.1 of the License, or (at your option) any later version.
00011 
00012    The GNU C Library is distributed in the hope that it will be useful,
00013    but WITHOUT ANY WARRANTY; without even the implied warranty of
00014    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015    Lesser General Public License for more details.
00016 
00017    You should have received a copy of the GNU Lesser General Public
00018    License along with the GNU C Library; if not, write to the Free
00019    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00020    02111-1307 USA.  */
00021 
00022 #ifndef _FPU_CONTROL_H
00023 # define _FPU_CONTROL_H
00024 
00025 # include <features.h>
00026 
00027 /* These bits are reserved are not changed.  */
00028 # define _FPU_RESERVED 0x070700FC
00029 
00030 /* The fdlibm code requires no interrupts for exceptions.  Don't
00031    change the rounding mode, it would break long double I/O!  */
00032 #define _FPU_DEFAULT  0x00000000 /* Default value.  */
00033 
00034 /* Type of the control word.  */
00035 typedef unsigned int fpu_control_t;
00036 
00037 /* Macros for accessing the hardware control word.  */
00038 #define _FPU_GETCW(cw)  __asm__ volatile ("efpc %0,0" : "=d" (cw))
00039 #define _FPU_SETCW(cw)  __asm__ volatile ("sfpc  %0,0" : : "d" (cw))
00040 
00041 /* Default control word set at startup.  */
00042 extern fpu_control_t __fpu_control;
00043 
00044 #endif /* _FPU_CONTROL_H */