whirl2f.h

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/*

  Copyright (C) 2000, 2001 Silicon Graphics, Inc.  All Rights Reserved.

  This program is free software; you can redistribute it and/or modify it
  under the terms of version 2 of the GNU General Public License as
  published by the Free Software Foundation.

  This program is distributed in the hope that it would be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  

  Further, this software is distributed without any warranty that it is
  free of the rightful claim of any third person regarding infringement 
  or the like.  Any license provided herein, whether implied or 
  otherwise, applies only to this software file.  Patent licenses, if 
  any, provided herein do not apply to combinations of this program with 
  other software, or any other product whatsoever.  

  You should have received a copy of the GNU General Public License along
  with this program; if not, write the Free Software Foundation, Inc., 59
  Temple Place - Suite 330, Boston MA 02111-1307, USA.

  Contact information:  Silicon Graphics, Inc., 1600 Amphitheatre Pky,
  Mountain View, CA 94043, or:

  http://www.sgi.com

  For further information regarding this notice, see:

  http://oss.sgi.com/projects/GenInfo/NoticeExplan

*/


#ifndef __WHIRL2F_H__
#define __WHIRL2F_H__



/* Assuming two's complement representation, we do this as follows
 * for a 32 bits integral type:
 *
 *   i >> n  ==>  ((-(2**n) | (i>>n))
 */
#define I4ASHR(v1, v2) \
   IOR(ISHFT(IAND('80000000'X, v1), -31)*ISHFT(-1, 32-v2), ISHFT(v1, -v2))
#define I8ASHR(v1, v2) \
   IOR(ISHFT(IAND('8000000000000000'X, v1), -63_8)*ISHFT(-1, 64-v2), ISHFT(v1, -v2))
#define U4ASHR(v1, v2) I4ASHR(v1, v2)
#define U8ASHR(v1, v2) I8ASHR(v1, v2)


/* See whirl2c.h for comments on this implementation of DIVFLOOR and
 * DIVCEIL.
 */
#define _I4SIGN(y) (2 * I4ASHR(y, 31) + 1)
#define _I4MASK(x, y, v) IAND(I4ASHR(IEOR(x,y), 31), v)
#define _I8SIGN(y) (2_8 * I8ASHR(y, 63) + 1_8)
#define _I8MASK(x, y, v) IAND(I8ASHR(IEOR(x,y), 63), v)

#define INTRN_I4DIVFLOOR(v1, v2) \
   ((v1) + _I4MASK(v1, v2, _I4SIGN(v2) - (v2))) / (v2)
#define INTRN_I8DIVFLOOR(v1, v2) \
   ((v1) + _I8MASK(v1, v2, _I8SIGN(v2) - (v2))) / (v2)
#define INTRN_U4DIVFLOOR(v1, v2) I4DIVFLOOR(v1, v2)
#define INTRN_U8DIVFLOOR(v1, v2) I8DIVFLOOR(v1, v2)

#define INTRN_I4DIVCEIL(v1, v2) -I4DIVFLOOR(-(v1), v2)
#define INTRN_I8DIVCEIL(v1, v2) -I8DIVFLOOR(-(v1), v2)
#define INTRN_U4DIVCEIL(v1, v2) ((v1)+(v2)-1)/(v2)
#define INTRN_U8DIVCEIL(v1, v2) ((v1)+(v2)-1)/(v2)

#define INTRN_I4MODFLOOR(v1, v2) (v1 - v2*I4DIVFLOOR(v1, v2))
#define INTRN_I8MODFLOOR(v1, v2) (v1 - v2*I8DIVFLOOR(v1, v2))
#define INTRN_U4MODFLOOR(v1, v2) (v1 - v2*(v1/v2))
#define INTRN_U8MODFLOOR(v1, v2) (v1 - v2*(v1/v2))

#define INTRN_I4MODCEIL(v1, v2) (v1 - v2*I4DIVCEIL(v1, v2))
#define INTRN_I8MODCEIL(v1, v2) (v1 - v2*I8DIVCEIL(v1, v2))
#define INTRN_U4MODCEIL(v1, v2) (v1 - v2*U4DIVCEIL(v1, v2))
#define INTRN_U8MODCEIL(v1, v2) (v1 - v2*U8DIVCEIL(v1, v2))


/* How do we do this without writing a function?
*/
#define CEIL(v) '?????TODO(CEIL)?????'
#define FLOOR(v) '?????TODO(FLOOR)?????'

#endif __WHIRL2F_H__