| /*- |
| * 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); |