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/* Set FP exception mask and rounding mode.
Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <fpu_control.h>
#include <asm/fpu.h>
extern void __ieee_set_fp_control (unsigned long);
extern unsigned long __ieee_get_fp_control (void);
static inline unsigned long
rdfpcr (void)
{
unsigned long fpcr;
asm ("excb; mf_fpcr %0" : "=f"(fpcr));
return fpcr;
}
static inline void
wrfpcr (unsigned long fpcr)
{
asm volatile ("mt_fpcr %0; excb" : : "f"(fpcr));
}
void
__setfpucw (fpu_control_t fpu_control)
{
unsigned long fpcr = 0, fpcw = 0;
if (!fpu_control)
fpu_control = _FPU_DEFAULT;
/* first, set dynamic rounding mode: */
fpcr = rdfpcr();
fpcr &= ~FPCR_DYN_MASK;
switch (fpu_control & 0xc00)
{
case _FPU_RC_NEAREST: fpcr |= FPCR_DYN_NORMAL; break;
case _FPU_RC_DOWN: fpcr |= FPCR_DYN_MINUS; break;
case _FPU_RC_UP: fpcr |= FPCR_DYN_PLUS; break;
case _FPU_RC_ZERO: fpcr |= FPCR_DYN_CHOPPED; break;
}
wrfpcr(fpcr);
/* now tell kernel about traps that we like to hear about: */
fpcw = __ieee_get_fp_control();
fpcw &= ~IEEE_TRAP_ENABLE_MASK;
if (!(fpu_control & _FPU_MASK_IM)) fpcw |= IEEE_TRAP_ENABLE_INV;
if (!(fpu_control & _FPU_MASK_DM)) fpcw |= IEEE_TRAP_ENABLE_UNF;
if (!(fpu_control & _FPU_MASK_ZM)) fpcw |= IEEE_TRAP_ENABLE_DZE;
if (!(fpu_control & _FPU_MASK_OM)) fpcw |= IEEE_TRAP_ENABLE_OVF;
if (!(fpu_control & _FPU_MASK_PM)) fpcw |= IEEE_TRAP_ENABLE_INE;
__fpu_control = fpu_control; /* update global copy */
__ieee_set_fp_control(fpcw);
}
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