The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/i386/include/ieeefp.h

Version: -  FREEBSD  -  FREEBSD-13-STABLE  -  FREEBSD-13-0  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  l41  -  OPENBSD  -  linux-2.6  -  MK84  -  PLAN9  -  xnu-8792 
SearchContext: -  none  -  3  -  10 

    1 /*-
    2  * Copyright (c) 1990 Andrew Moore, Talke Studio
    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  * 3. All advertising materials mentioning features or use of this software
   14  *    must display the following acknowledgement:
   15  *      This product includes software developed by the University of
   16  *      California, Berkeley and its contributors.
   17  * 4. Neither the name of the University nor the names of its contributors
   18  *    may be used to endorse or promote products derived from this software
   19  *    without specific prior written permission.
   20  *
   21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   31  * SUCH DAMAGE.
   32  *
   33  *      from: @(#) ieeefp.h     1.0 (Berkeley) 9/23/93
   34  * $FreeBSD: releng/5.2/sys/i386/include/ieeefp.h 109520 2003-01-19 06:01:33Z marcel $
   35  */
   36 
   37 /*
   38  *      IEEE floating point type and constant definitions.
   39  */
   40 
   41 #ifndef _MACHINE_IEEEFP_H_
   42 #define _MACHINE_IEEEFP_H_
   43 
   44 /*
   45  * FP rounding modes
   46  */
   47 typedef enum {
   48         FP_RN=0,        /* round to nearest */
   49         FP_RM,          /* round down to minus infinity */
   50         FP_RP,          /* round up to plus infinity */
   51         FP_RZ           /* truncate */
   52 } fp_rnd_t;
   53 
   54 /*
   55  * FP precision modes
   56  */
   57 typedef enum {
   58         FP_PS=0,        /* 24 bit (single-precision) */
   59         FP_PRS,         /* reserved */
   60         FP_PD,          /* 53 bit (double-precision) */
   61         FP_PE           /* 64 bit (extended-precision) */
   62 } fp_prec_t;
   63 
   64 #define fp_except_t     int
   65 
   66 /*
   67  * FP exception masks
   68  */
   69 #define FP_X_INV        0x01    /* invalid operation */
   70 #define FP_X_DNML       0x02    /* denormal */
   71 #define FP_X_DZ         0x04    /* zero divide */
   72 #define FP_X_OFL        0x08    /* overflow */
   73 #define FP_X_UFL        0x10    /* underflow */
   74 #define FP_X_IMP        0x20    /* (im)precision */
   75 #define FP_X_STK        0x40    /* stack fault */
   76 
   77 /*
   78  * FP registers
   79  */
   80 #define FP_MSKS_REG     0       /* exception masks */
   81 #define FP_PRC_REG      0       /* precision */
   82 #define FP_RND_REG      0       /* direction */
   83 #define FP_STKY_REG     1       /* sticky flags */
   84 
   85 /*
   86  * FP register bit field masks
   87  */
   88 #define FP_MSKS_FLD     0x3f    /* exception masks field */
   89 #define FP_PRC_FLD      0x300   /* precision control field */
   90 #define FP_RND_FLD      0xc00   /* round control field */
   91 #define FP_STKY_FLD     0x3f    /* sticky flags field */
   92 
   93 /*
   94  * FP register bit field offsets
   95  */
   96 #define FP_MSKS_OFF     0       /* exception masks offset */
   97 #define FP_PRC_OFF      8       /* precision control offset */
   98 #define FP_RND_OFF      10      /* round control offset */
   99 #define FP_STKY_OFF     0       /* sticky flags offset */
  100 
  101 #ifdef __GNUC__
  102 
  103 #define __fldenv(addr)  __asm __volatile("fldenv %0" : : "m" (*(addr)))
  104 #define __fnstenv(addr) __asm __volatile("fnstenv %0" : "=m" (*(addr)))
  105 #define __fnstcw(addr)  __asm __volatile("fnstcw %0" : "=m" (*(addr)))
  106 #define __fnstsw(addr)  __asm __volatile("fnstsw %0" : "=m" (*(addr)))
  107 
  108 /*
  109  * return the contents of a FP register
  110  */
  111 static __inline__ int
  112 __fpgetreg(int _reg)
  113 {
  114         unsigned short _mem;
  115 
  116         /*-
  117          * This is more efficient than it looks.  The switch gets optimized
  118          * away if _reg is constant.
  119          *
  120          * The default case only supports _reg == 0.  We could handle more
  121          * registers (e.g., tags) using fnstenv, but the interface doesn't
  122          * support more.
  123          */
  124         switch(_reg) {
  125         default:
  126                 __fnstcw(&_mem);
  127                 break;
  128         case FP_STKY_REG:
  129                 __fnstsw(&_mem);
  130                 break;
  131         }
  132         return _mem;
  133 }
  134 
  135 /*
  136  * set a FP mode; return previous mode
  137  */
  138 static __inline__ int
  139 __fpsetreg(int _m, int _reg, int _fld, int _off)
  140 {
  141         unsigned _env[7];
  142         unsigned _p;
  143 
  144         /*
  145          * _reg == 0 could be handled better using fnstcw/fldcw.
  146          */
  147         __fnstenv(_env);
  148         _p =  (_env[_reg] & _fld) >> _off;
  149         _env[_reg] = (_env[_reg] & ~_fld) | (_m << _off & _fld);
  150         __fldenv(_env);
  151         return _p;
  152 }
  153 
  154 #endif /* __GNUC__ */
  155 
  156 /*
  157  * SysV/386 FP control interface
  158  */
  159 #define fpgetround()    ((fp_rnd_t)                                     \
  160         ((__fpgetreg(FP_RND_REG) & FP_RND_FLD) >> FP_RND_OFF))
  161 #define fpsetround(m)   ((fp_rnd_t)                                     \
  162         __fpsetreg((m), FP_RND_REG, FP_RND_FLD, FP_RND_OFF))
  163 #define fpgetprec()     ((fp_prec_t)                                    \
  164         ((__fpgetreg(FP_PRC_REG) & FP_PRC_FLD) >> FP_PRC_OFF))
  165 #define fpsetprec(m)    ((fp_prec_t)                                    \
  166         __fpsetreg((m), FP_PRC_REG, FP_PRC_FLD, FP_PRC_OFF))
  167 #define fpgetmask()     ((fp_except_t)                                  \
  168         ((~__fpgetreg(FP_MSKS_REG) & FP_MSKS_FLD) >> FP_MSKS_OFF))
  169 #define fpsetmask(m)    ((fp_except_t)                                  \
  170         (~__fpsetreg(~(m), FP_MSKS_REG, FP_MSKS_FLD, FP_MSKS_OFF)) &    \
  171             (FP_MSKS_FLD >> FP_MSKS_OFF))
  172 #define fpgetsticky()   ((fp_except_t)                                  \
  173         ((__fpgetreg(FP_STKY_REG) & FP_STKY_FLD) >> FP_STKY_OFF))
  174 #define fpresetsticky(m) ((fp_except_t)                                 \
  175         __fpsetreg(0, FP_STKY_REG, (m), FP_STKY_OFF))
  176 #define fpsetsticky(m)  fpresetsticky(m)
  177 
  178 /* Suppress prototypes in the MI header. */
  179 #define _IEEEFP_INLINED_        1
  180 
  181 #endif /* !_MACHINE_IEEEFP_H_ */

Cache object: 1444cb861739efce3854a5a6cfc6b9a1


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.