Add copyright.

(rdfpcr): Use excb rather than trapb.  Be more efficient about
getting at the fpcr.
(wrfpcr): Likewise.
(__setfpucw): Reformat.
This commit is contained in:
Ulrich Drepper 1997-05-31 00:46:15 +00:00
parent 2521516d30
commit f97d5b5f4d
2 changed files with 67 additions and 54 deletions

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@ -1,23 +1,22 @@
/* FPU control word bits. Alpha version. /* FPU control word bits. Alpha-maped-to-Intel version.
Copyright (C) 1996 Free Software Foundation, Inc. Copyright (C) 1996 Free Software Foundation, Inc.
Contributed by Olaf Flebbe. This file is part of the GNU C Library.
Contributed by Olaf Flebbe.
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 free software; you can redistribute it and/or The GNU C Library is distributed in the hope that it will be useful,
modify it under the terms of the GNU Library General Public License as but WITHOUT ANY WARRANTY; without even the implied warranty of
published by the Free Software Foundation; either version 2 of the MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
License, or (at your option) any later version. Library General Public License for more details.
The GNU C Library is distributed in the hope that it will be useful, You should have received a copy of the GNU Library General Public
but WITHOUT ANY WARRANTY; without even the implied warranty of License along with the GNU C Library; see the file COPYING.LIB. If not,
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Library General Public License for more details. Boston, MA 02111-1307, USA. */
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., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#ifndef _ALPHA_FPU_CONTROL_H #ifndef _ALPHA_FPU_CONTROL_H
#define _ALPHA_FPU_CONTROL_H #define _ALPHA_FPU_CONTROL_H
@ -91,11 +90,12 @@ Cambridge, MA 02139, USA. */
qualifier. By setting the dynamic rounding mode to +infinity, qualifier. By setting the dynamic rounding mode to +infinity,
one can use /d to get round to +infinity with no extra overhead one can use /d to get round to +infinity with no extra overhead
(so long as the default isn't changed, of course...) (so long as the default isn't changed, of course...)
- exceptions on overflow, zero divide and NaN */ - no exceptions enabled. */
#define _FPU_DEFAULT 0x1f72
#define _FPU_DEFAULT 0x137f
/* IEEE: same as above, but exceptions */ /* IEEE: same as above, but exceptions */
#define _FPU_IEEE 0x1f7f #define _FPU_IEEE 0x137f
/* Type of the control word. */ /* Type of the control word. */
typedef unsigned int fpu_control_t; typedef unsigned int fpu_control_t;

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@ -1,65 +1,78 @@
#include <fpu_control.h> /* 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> #include <asm/fpu.h>
extern void __ieee_set_fp_control (unsigned long); extern void __ieee_set_fp_control (unsigned long);
extern unsigned long __ieee_get_fp_control (void); extern unsigned long __ieee_get_fp_control (void);
static inline unsigned long static inline unsigned long
rdfpcr (void) rdfpcr (void)
{ {
unsigned long fpcr; unsigned long fpcr;
asm ("excb; mf_fpcr %0" : "=f"(fpcr));
asm ("trapb; mf_fpcr $f0; trapb; stt $f0,%0" : "m="(fpcr)); return fpcr;
return fpcr;
} }
static inline void static inline void
wrfpcr (unsigned long fpcr) wrfpcr (unsigned long fpcr)
{ {
asm volatile ("ldt $f0,%0; trapb; mt_fpcr $f0; trapb" :: "m"(fpcr)); asm volatile ("mt_fpcr %0; excb" : : "f"(fpcr));
} }
void void
__setfpucw (unsigned short fpu_control) __setfpucw (unsigned short fpu_control)
{ {
unsigned long fpcr = 0, fpcw = 0; unsigned long fpcr = 0, fpcw = 0;
if (!fpu_control) if (!fpu_control)
fpu_control = _FPU_DEFAULT; fpu_control = _FPU_DEFAULT;
/* first, set dynamic rounding mode: */ /* first, set dynamic rounding mode: */
fpcr = rdfpcr(); fpcr = rdfpcr();
fpcr &= ~FPCR_DYN_MASK; fpcr &= ~FPCR_DYN_MASK;
switch (fpu_control & 0xc00) { 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_NEAREST: fpcr |= FPCR_DYN_NORMAL; break;
case _FPU_RC_UP: fpcr |= FPCR_DYN_PLUS; break; case _FPU_RC_DOWN: fpcr |= FPCR_DYN_MINUS; break;
case _FPU_RC_ZERO: fpcr |= FPCR_DYN_CHOPPED; break; case _FPU_RC_UP: fpcr |= FPCR_DYN_PLUS; break;
case _FPU_RC_ZERO: fpcr |= FPCR_DYN_CHOPPED; break;
} }
wrfpcr(fpcr); wrfpcr(fpcr);
/* now tell kernel about traps that we like to hear about: */ /* now tell kernel about traps that we like to hear about: */
fpcw = __ieee_get_fp_control(); fpcw = __ieee_get_fp_control();
fpcw &= ~IEEE_TRAP_ENABLE_MASK; fpcw &= ~IEEE_TRAP_ENABLE_MASK;
if (!(fpu_control & _FPU_MASK_IM)) if (!(fpu_control & _FPU_MASK_IM)) fpcw |= IEEE_TRAP_ENABLE_INV;
fpcw |= IEEE_TRAP_ENABLE_INV; if (!(fpu_control & _FPU_MASK_DM)) fpcw |= IEEE_TRAP_ENABLE_UNF;
if (!(fpu_control & _FPU_MASK_DM)) if (!(fpu_control & _FPU_MASK_ZM)) fpcw |= IEEE_TRAP_ENABLE_DZE;
fpcw |= IEEE_TRAP_ENABLE_UNF; if (!(fpu_control & _FPU_MASK_OM)) fpcw |= IEEE_TRAP_ENABLE_OVF;
if (!(fpu_control & _FPU_MASK_ZM)) if (!(fpu_control & _FPU_MASK_PM)) fpcw |= IEEE_TRAP_ENABLE_INE;
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;
__ieee_set_fp_control(fpcw); __fpu_control = fpu_control; /* update global copy */
__fpu_control = fpu_control; /* update global copy */ __ieee_set_fp_control(fpcw);
} }