/*
 * Copyright (c) 2002, The Tendra Project <http://www.ten15.org/>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice unmodified, this list of conditions, and the following
 *    disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *
 *    		 Crown Copyright (c) 1997
 *
 *    This TenDRA(r) Computer Program is subject to Copyright
 *    owned by the United Kingdom Secretary of State for Defence
 *    acting through the Defence Evaluation and Research Agency
 *    (DERA).  It is made available to Recipients with a
 *    royalty-free licence for its use, reproduction, transfer
 *    to other parties and amendment for any purpose not excluding
 *    product development provided that any such use et cetera
 *    shall be deemed to be acceptance of the following conditions:-
 *
 *        (1) Its Recipients shall ensure that this Notice is
 *        reproduced upon any copies or amended versions of it;
 *
 *        (2) Any amended version of it shall be clearly marked to
 *        show both the nature of and the organisation responsible
 *        for the relevant amendment or amendments;
 *
 *        (3) Its onward transfer from a recipient to another
 *        party shall be deemed to be that party's acceptance of
 *        these conditions;
 *
 *        (4) DERA gives no warranty or assurance as to its
 *        quality or suitability for any purpose and DERA accepts
 *        no liability whatsoever in relation to any use to which
 *        it may be put.
 *
 * $TenDRA: tendra/src/installers/mips/common/regable.c,v 1.6 2004/06/28 03:31:05 bp Exp $
 */


/******************************************************************
 *		regable.c

******************************************************************/


#include "config.h"
#include "expmacs.h"
#include "common_types.h"
#include "shapemacs.h"
#include "tags.h"
#include "regable.h"

/***************************************************************
 *	fixregable
 *
 *determines whether the exp e can fit in a single fixed point register. Uses
 *macros isvis, isglob, iscaonly from expmacs.h which examine the props
 *field. The iscaonly bit is set by proc independent if the tag is only used
 *by the contents operator or as the left hand side of an assignment. The
 *procedure also uses the macro is_floating from shapemacs.h which checks
 *the shape number is in the range for floating point shapes.
 ****************************************************************/


bool
valregable(shape s)
{
	int n = name(s);
	if (is_floating (n)) {	/* check shape to see if floating point */
		return 0;
	}
	else {
		ash a;
		a = ashof (s);		/* get ash corresponding to shape of e */
		
/* ALTERATION #1 */
		return (a.ashsize <=32  && n!=cpdhd && n!= nofhd && n!=tophd);
		
	}
}

bool
fixregable(exp e)
{
	if (!isvis (e) && !isoutpar(e) && !isglob (e)
		&& name(son(e)) != caller_name_tag) {
		shape s = sh (son (e));	/* son of ident exp is def */
		return valregable (s);
	}
	else {
		return 0;
	}
}

/***************************************************************
 *	floatregable
 *
 *determines whether the exp e can fit in a floating point register, single
 *or double.
 ***************************************************************/

bool
floatregable(exp e)
{
	if (!isvis (e) && !isoutpar(e) && !isglob (e)
		&& name(son(e)) != caller_name_tag) {
		shape s = sh (son (e));
		if is_floating
			(name (s)) {
			return 1;
		}
		else {
			return 0;
		}
	}
	else {
		return 0;
	}
}
