/* FPU control word bits.  Alpha-mapped-to-Intel version.

   Copyright (C) 1996-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   Contributed by Olaf Flebbe.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 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

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library.  If not, see

   <http://www.gnu.org/licenses/>.  */

#ifndef _ALPHA_FPU_CONTROL_H

#define _ALPHA_FPU_CONTROL_H

/*

 * Since many programs seem to hardcode the values passed to __setfpucw()

 * (rather than using the manifest constants) we emulate the x87 interface

 * here (at least where this makes sense).

 *

 *     15-13    12  11-10  9-8     7-6     5    4    3    2    1    0

 * | reserved | IC | RC  | PC | reserved | PM | UM | OM | ZM | DM | IM

 *

 * IM: Invalid operation mask

 * DM: Denormalized operand mask

 * ZM: Zero-divide mask

 * OM: Overflow mask

 * UM: Underflow mask

 * PM: Precision (inexact result) mask

 *

 * Mask bit is 1 means no interrupt.

 *

 * PC: Precision control

 * 11 - round to extended precision

 * 10 - round to double precision

 * 00 - round to single precision

 *

 * RC: Rounding control

 * 00 - rounding to nearest

 * 01 - rounding down (toward - infinity)

 * 10 - rounding up (toward + infinity)

 * 11 - rounding toward zero

 *

 * IC: Infinity control

 * That is for 8087 and 80287 only.

 *

 * The hardware default is 0x037f. I choose 0x1372.

 */

#include <features.h>

/* masking of interrupts */

#define _FPU_MASK_IM  0x01

#define _FPU_MASK_DM  0x02

#define _FPU_MASK_ZM  0x04

#define _FPU_MASK_OM  0x08

#define _FPU_MASK_UM  0x10

#define _FPU_MASK_PM  0x20

/* precision control -- without effect on Alpha */

#define _FPU_EXTENDED 0x300   /* RECOMMENDED */

#define _FPU_DOUBLE   0x200

#define _FPU_SINGLE   0x0     /* DO NOT USE */

/*

 * rounding control---notice that on the Alpha this affects only

 * instructions with the dynamic rounding mode qualifier (/d).

 */

#define _FPU_RC_NEAREST 0x000 /* RECOMMENDED */

#define _FPU_RC_DOWN    0x400

#define _FPU_RC_UP      0x800

#define _FPU_RC_ZERO    0xC00

#define _FPU_RESERVED 0xF0C0  /* Reserved bits in cw */

/* Now two recommended cw */

/* Linux default:

     - extended precision

     - rounding to positive infinity.  There is no /p instruction

       qualifier.  By setting the dynamic rounding mode to +infinity,

       one can use /d to get round to +infinity with no extra overhead

       (so long as the default isn't changed, of course...)

     - no exceptions enabled.  */

#define _FPU_DEFAULT  0x137f

/* IEEE:  same as above. */

#define _FPU_IEEE     0x137f

/* Type of the control word.  */

typedef unsigned int fpu_control_t;

/* Default control word set at startup.  */

extern fpu_control_t __fpu_control;

#endif	/* _ALPHA_FPU_CONTROL */