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/*-
* 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/amd64/fenv.c,v 1.3 2005/03/16 19:03:45 das Exp $
*/
#include <sys/cdefs.h>
#include <sys/types.h>
#include <machine/fpu.h>
#include <fenv.h>
const fenv_t __fe_dfl_env = {
{ 0xffff0000 | __INITIAL_FPUCW__,
0xffff0000,
0xffffffff,
{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff }
},
__INITIAL_MXCSR__
};
int
fesetexceptflag(const fexcept_t *flagp, int excepts)
{
fenv_t env;
__fnstenv(&env.__x87);
env.__x87.__status &= ~excepts;
env.__x87.__status |= *flagp & excepts;
__fldenv(env.__x87);
__stmxcsr(&env.__mxcsr);
env.__mxcsr &= ~excepts;
env.__mxcsr |= *flagp & excepts;
__ldmxcsr(env.__mxcsr);
return (0);
}
int
feraiseexcept(int excepts)
{
fexcept_t ex = excepts;
fesetexceptflag(&ex, excepts);
__fwait();
return (0);
}
int
fegetenv(fenv_t *envp)
{
int control;
/*
* fnstenv masks all exceptions, so we need to save and
* restore the control word to avoid this side effect.
*/
__fnstcw(&control);
__fnstenv(&envp->__x87);
__stmxcsr(&envp->__mxcsr);
__fldcw(control);
return (0);
}
int
feholdexcept(fenv_t *envp)
{
int mxcsr;
__stmxcsr(&mxcsr);
__fnstenv(&envp->__x87);
__fnclex();
envp->__mxcsr = mxcsr;
mxcsr &= ~FE_ALL_EXCEPT;
mxcsr |= FE_ALL_EXCEPT << _SSE_EMASK_SHIFT;
__ldmxcsr(mxcsr);
return (0);
}
int
feupdateenv(const fenv_t *envp)
{
int mxcsr, status;
__fnstsw(&status);
__stmxcsr(&mxcsr);
fesetenv(envp);
feraiseexcept((mxcsr | status) & FE_ALL_EXCEPT);
return (0);
}
int
__feenableexcept(int mask)
{
int mxcsr, control, omask;
mask &= FE_ALL_EXCEPT;
__fnstcw(&control);
__stmxcsr(&mxcsr);
omask = (control | mxcsr >> _SSE_EMASK_SHIFT) & FE_ALL_EXCEPT;
control &= ~mask;
__fldcw(control);
mxcsr &= ~(mask << _SSE_EMASK_SHIFT);
__ldmxcsr(mxcsr);
return (~omask);
}
int
__fedisableexcept(int mask)
{
int mxcsr, control, omask;
mask &= FE_ALL_EXCEPT;
__fnstcw(&control);
__stmxcsr(&mxcsr);
omask = (control | mxcsr >> _SSE_EMASK_SHIFT) & FE_ALL_EXCEPT;
control |= mask;
__fldcw(control);
mxcsr |= mask << _SSE_EMASK_SHIFT;
__ldmxcsr(mxcsr);
return (~omask);
}
__weak_reference(__feenableexcept, feenableexcept);
__weak_reference(__fedisableexcept, fedisableexcept);
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