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Diffstat (limited to 'libm/alpha/fenv.h')
| -rw-r--r-- | libm/alpha/fenv.h | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/libm/alpha/fenv.h b/libm/alpha/fenv.h new file mode 100644 index 0000000..dc7bcb7 --- /dev/null +++ b/libm/alpha/fenv.h @@ -0,0 +1,185 @@ +/*- + * Copyright (c) 2004-2005 David Schultz <das@FreeBSD.ORG> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $FreeBSD: src/lib/msun/alpha/fenv.h,v 1.3 2005/03/16 19:03:44 das Exp $ + */ + +#ifndef _FENV_H_ +#define _FENV_H_ + +#include <sys/_types.h> + +typedef __uint64_t fenv_t; +typedef __uint16_t fexcept_t; + +/* Exception flags */ +#define FE_INVALID 0x02 +#define FE_DIVBYZERO 0x04 +#define FE_OVERFLOW 0x08 +#define FE_UNDERFLOW 0x10 +#define FE_INEXACT 0x20 +#define FE_INTOVF 0x40 /* not maskable */ +#define FE_ALL_EXCEPT (FE_DIVBYZERO | FE_INEXACT | FE_INTOVF | \ + FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW) + +/* Rounding modes */ +#define FE_TOWARDZERO 0x00 +#define FE_DOWNWARD 0x01 +#define FE_TONEAREST 0x02 +#define FE_UPWARD 0x03 +#define _ROUND_MASK (FE_TONEAREST | FE_DOWNWARD | \ + FE_UPWARD | FE_TOWARDZERO) +#define _ROUND_SHIFT 58 + +#define _FPUSW_SHIFT 51 + +#define __excb() __asm __volatile("excb") +#define __mf_fpcr(__cw) __asm __volatile("mf_fpcr %0" : "=f" (*(__cw))) +#define __mt_fpcr(__cw) __asm __volatile("mt_fpcr %0" : : "f" (__cw)) + +union __fpcr { + double __d; + fenv_t __bits; +}; + +__BEGIN_DECLS + +/* Default floating-point environment */ +extern const fenv_t __fe_dfl_env; +#define FE_DFL_ENV (&__fe_dfl_env) + +static __inline int +feclearexcept(int __excepts) +{ + union __fpcr __r; + + __excb(); + __mf_fpcr(&__r.__d); + __r.__bits &= ~((fenv_t)__excepts << _FPUSW_SHIFT); + __mt_fpcr(__r.__d); + __excb(); + return (0); +} + +static __inline int +fegetexceptflag(fexcept_t *__flagp, int __excepts) +{ + union __fpcr __r; + + __excb(); + __mf_fpcr(&__r.__d); + __excb(); + *__flagp = (__r.__bits >> _FPUSW_SHIFT) & __excepts; + return (0); +} + +static __inline int +fesetexceptflag(const fexcept_t *__flagp, int __excepts) +{ + union __fpcr __r; + fenv_t __xflag, __xexcepts; + + __xflag = (fenv_t)*__flagp << _FPUSW_SHIFT; + __xexcepts = (fenv_t)__excepts << _FPUSW_SHIFT; + __excb(); + __mf_fpcr(&__r.__d); + __r.__bits &= ~__xexcepts; + __r.__bits |= __xflag & __xexcepts; + __mt_fpcr(__r.__d); + __excb(); + return (0); +} + +static __inline int +feraiseexcept(int __excepts) +{ + + /* + * XXX Generating exceptions this way does not actually invoke + * a userland trap handler when enabled, but neither do + * arithmetic operations as far as I can tell. Perhaps there + * are more bugs in the kernel trap handler. + */ + fexcept_t __ex = __excepts; + fesetexceptflag(&__ex, __excepts); + return (0); +} + +static __inline int +fetestexcept(int __excepts) +{ + union __fpcr __r; + + __excb(); + __mf_fpcr(&__r.__d); + __excb(); + return ((__r.__bits >> _FPUSW_SHIFT) & __excepts); +} + +static __inline int +fegetround(void) +{ + union __fpcr __r; + + /* + * No exception barriers should be required here if we assume + * that only fesetround() can change the rounding mode. + */ + __mf_fpcr(&__r.__d); + return ((int)(__r.__bits >> _ROUND_SHIFT) & _ROUND_MASK); +} + +static __inline int +fesetround(int __round) +{ + union __fpcr __r; + + if (__round & ~_ROUND_MASK) + return (-1); + __excb(); + __mf_fpcr(&__r.__d); + __r.__bits &= ~((fenv_t)_ROUND_MASK << _ROUND_SHIFT); + __r.__bits |= (fenv_t)__round << _ROUND_SHIFT; + __mt_fpcr(__r.__d); + __excb(); + return (0); +} + +int fegetenv(fenv_t *__envp); +int feholdexcept(fenv_t *__envp); +int fesetenv(const fenv_t *__envp); +int feupdateenv(const fenv_t *__envp); + +#if __BSD_VISIBLE + +int feenableexcept(int __mask); +int fedisableexcept(int __mask); +int fegetexcept(void); + +#endif /* __BSD_VISIBLE */ + +__END_DECLS + +#endif /* !_FENV_H_ */ |