mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-02 17:50:20 +00:00
f97d5b5f4d
(rdfpcr): Use excb rather than trapb. Be more efficient about getting at the fpcr. (wrfpcr): Likewise. (__setfpucw): Reformat.
79 lines
2.3 KiB
C
79 lines
2.3 KiB
C
/* Set FP exception mask and rounding mode.
|
|
Copyright (C) 1996, 1997 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 (unsigned short 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);
|
|
}
|