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Diffstat (limited to 'libm/alpha/fenv.c')
| -rw-r--r-- | libm/alpha/fenv.c | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/libm/alpha/fenv.c b/libm/alpha/fenv.c new file mode 100644 index 0000000..e8ab204 --- /dev/null +++ b/libm/alpha/fenv.c @@ -0,0 +1,144 @@ +/*- + * 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.c,v 1.2 2005/03/16 19:03:44 das Exp $ + */ + +#include <sys/cdefs.h> +#include <machine/sysarch.h> +#include <fenv.h> + +const fenv_t __fe_dfl_env = 0x680e000000000000ULL; + +struct mask_args { + fenv_t mask; +}; + +/* + * The lower 49 bits of the FPCR are unused by the hardware, so we use + * the lower order bits to store the kernel's idea of the FP mask as + * described in the Alpha Architecture Manual. + */ +int +fegetenv(fenv_t *envp) +{ + struct mask_args p; + union __fpcr r; + + /* + * The syscall acts as an implicit exception barrier, so we + * only need to issue an excb after the mf_fpcr to ensure that + * the read is executed before any subsequent FP ops. + */ + sysarch(ALPHA_GET_FPMASK, (char *)&p); + __mf_fpcr(&r.__d); + *envp = r.__bits | p.mask; + __excb(); + return (0); +} + +int +feholdexcept(fenv_t *envp) +{ + struct mask_args p; + union __fpcr r; + + sysarch(ALPHA_GET_FPMASK, (char *)&p); + __mf_fpcr(&r.__d); + *envp = r.__bits | p.mask; + r.__bits &= ~((fenv_t)FE_ALL_EXCEPT << _FPUSW_SHIFT); + __mt_fpcr(r.__d); + if (p.mask & FE_ALL_EXCEPT) { + p.mask = 0; + sysarch(ALPHA_SET_FPMASK, &p); + } + __excb(); + return (0); +} + +int +fesetenv(const fenv_t *envp) +{ + struct mask_args p; + union __fpcr r; + + p.mask = *envp & FE_ALL_EXCEPT; + sysarch(ALPHA_SET_FPMASK, &p); + r.__bits = *envp & ~FE_ALL_EXCEPT; + __mt_fpcr(r.__d); + __excb(); + return (0); +} + +int +feupdateenv(const fenv_t *envp) +{ + struct mask_args p; + union __fpcr oldr, newr; + + p.mask = *envp & FE_ALL_EXCEPT; + sysarch(ALPHA_SET_FPMASK, &p); + __mf_fpcr(&oldr.__d); + newr.__bits = *envp & ~FE_ALL_EXCEPT; + __excb(); + __mt_fpcr(newr.__d); + feraiseexcept((oldr.__bits >> _FPUSW_SHIFT) & FE_ALL_EXCEPT); + return (0); +} + +int +__feenableexcept(int mask) +{ + struct mask_args p; + + sysarch(ALPHA_GET_FPMASK, &p); + p.mask |= (mask & FE_ALL_EXCEPT); + sysarch(ALPHA_SET_FPMASK, &p); + return (p.mask); +} + +int +__fedisableexcept(int mask) +{ + struct mask_args p; + + sysarch(ALPHA_GET_FPMASK, &p); + p.mask &= ~(mask & FE_ALL_EXCEPT); + sysarch(ALPHA_SET_FPMASK, &p); + return (p.mask); +} + +int +__fegetexcept(void) +{ + struct mask_args p; + + sysarch(ALPHA_GET_FPMASK, &p); + return (p.mask); +} + +__weak_reference(__feenableexcept, feenableexcept); +__weak_reference(__fedisableexcept, fedisableexcept); +__weak_reference(__fegetexcept, fegetexcept); |