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glibc  2.9
fpu_control.h
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00001 /* FPU control word definitions.  SH version.
00002    Copyright (C) 1999, 2000 Free Software Foundation, Inc.
00003    This file is part of the GNU C Library.
00004 
00005    The GNU C Library is free software; you can redistribute it and/or
00006    modify it under the terms of the GNU Lesser General Public
00007    License as published by the Free Software Foundation; either
00008    version 2.1 of the License, or (at your option) any later version.
00009 
00010    The GNU C Library is distributed in the hope that it will be useful,
00011    but WITHOUT ANY WARRANTY; without even the implied warranty of
00012    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00013    Lesser General Public License for more details.
00014 
00015    You should have received a copy of the GNU Lesser General Public
00016    License along with the GNU C Library; if not, write to the Free
00017    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00018    02111-1307 USA.  */
00019 
00020 #ifndef _FPU_CONTROL_H
00021 #define _FPU_CONTROL_H
00022 
00023 /* masking of interrupts */
00024 #define _FPU_MASK_VM 0x0800 /* Invalid operation */
00025 #define _FPU_MASK_ZM 0x0400 /* Division by zero  */
00026 #define _FPU_MASK_OM 0x0200 /* Overflow        */
00027 #define _FPU_MASK_UM 0x0100 /* Underflow       */
00028 #define _FPU_MASK_IM 0x0080 /* Inexact operation */
00029 
00030 /* rounding control */
00031 #define _FPU_RC_NEAREST 0x0 /* RECOMMENDED */
00032 #define _FPU_RC_ZERO 0x1
00033 
00034 #define _FPU_RESERVED 0xffc00000  /* These bits are reserved.  */
00035 
00036 /* The fdlibm code requires strict IEEE double precision arithmetic,
00037    and no interrupts for exceptions, rounding to nearest.  */
00038 #define _FPU_DEFAULT 0x00080000 /* Default value.  */
00039 #define _FPU_IEEE    0x00080f80 /* Default + exceptions enabled. */
00040 
00041 /* Type of the control word.  */
00042 typedef unsigned int fpu_control_t;
00043 
00044 /* Macros for accessing the hardware control word.  */
00045 #define _FPU_GETCW(cw) __asm__ ("sts fpscr,%0" : "=r" (cw))
00046 
00047 #if defined __GNUC__
00048 #define _FPU_SETCW(cw) __set_fpscr ((cw))
00049 #else
00050 #define _FPU_SETCW(cw) __asm__ ("lds %0,fpscr" : : "r" (cw))
00051 #endif
00052 
00053 /* Default control word set at startup.    */
00054 extern fpu_control_t __fpu_control;
00055 
00056 #endif /* _FPU_CONTROL_H */