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#ifndef __netmisc_H
#define __netmisc_H
/*
* Copyright (c) 1999-2000 Stephen Williams (steve@icarus.com)
*
* This source code is free software; you can redistribute it
* and/or modify it in source code form under the terms of the GNU
* General Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#ifdef HAVE_CVS_IDENT
#ident "$Id: netmisc.h,v 1.26 2006/09/28 00:29:49 steve Exp $"
#endif
# include "netlist.h"
/*
* Search for a symbol using the "start" scope as the starting
* point. If the path includes a scope part, then locate the
* scope first.
*
* The return value is the scope where the symbol was found.
* If the symbol was not found, return 0. The output arguments
* get 0 except for the pointer to the object that represents
* the located symbol.
*
* The ex1 and ex2 output arguments are extended results. If the
* symbol is a parameter (par!=0) then ex1 is the msb expression and
* ex2 is the lsb expression for the range. If there is no range, then
* these values are set to 0.
*/
extern NetScope* symbol_search(const Design*des,
NetScope*start, hname_t path,
NetNet*&net, /* net/reg */
NetMemory*&mem, /* memory */
const NetExpr*&par,/* parameter */
NetEvent*&eve, /* named event */
const NetExpr*&ex1, const NetExpr*&ex2);
inline NetScope* symbol_search(const Design*des,
NetScope*start, const hname_t&path,
NetNet*&net, /* net/reg */
NetMemory*&mem, /* memory */
const NetExpr*&par,/* parameter */
NetEvent*&eve /* named event */)
{
const NetExpr*ex1, *ex2;
return symbol_search(des, start, path, net, mem, par, eve, ex1, ex2);
}
/*
* This function transforms an expression by padding the high bits
* with V0 until the expression has the desired width. This may mean
* not transforming the expression at all, if it is already wide
* enough.
*/
extern NetExpr*pad_to_width(NetExpr*expr, unsigned wid);
extern NetNet*pad_to_width(Design*des, NetNet*n, unsigned w);
extern NetNet*pad_to_width_signed(Design*des, NetNet*n, unsigned w);
/*
* This function transforms an expression by cropping the high bits
* off with a part select. The result has the width w passed in. This
* function does not pad, use pad_to_width if padding is desired.
*/
extern NetNet*crop_to_width(Design*des, NetNet*n, unsigned w);
/*
* This function takes as input a NetNet signal and adds a constant
* value to it. If the val is 0, then simply return sig. Otherwise,
* return a new NetNet value that is the output of an addition.
*/
extern NetNet*add_to_net(Design*des, NetNet*sig, long val);
/*
* These functions make various sorts of expressions, given operands
* of certain type. The order of the operands is preserved in cases
* where order matters.
*
* make_add_expr
* Make a NetEBAdd expresion with <expr> the first argument and
* <val> the second. This may get turned into a subtract if <val> is
* less then zero. If val is exactly zero, then return <expr> as is.
*
* make_sub_expr
* Make a NetEBAdd(subtract) node that subtracts the given
* expression from the integer value.
*/
extern NetExpr*make_add_expr(NetExpr*expr, long val);
extern NetExpr*make_sub_expr(long val, NetExpr*expr);
/*
* In some cases the lval is accessible as a pointer to the head of
* a list of NetAssign_ objects. This function returns the width of
* the l-value represented by this list.
*/
extern unsigned count_lval_width(const class NetAssign_*first);
/*
* This function elaborates an expression, and tries to evaluate it
* right away. If the expression can be evaluated, this returns a
* constant expression. If it cannot be evaluated, it returns whatever
* it can. If the expression cannot be elaborated, return 0.
*
* The expr_width is the width of the context where the expression is
* being elaborated, or -1 if the expression is self-determinted width.
*/
class PExpr;
extern NetExpr* elab_and_eval(Design*des, NetScope*scope,
const PExpr*pe, int expr_wid);
/*
* $Log: netmisc.h,v $
* Revision 1.26 2006/09/28 00:29:49 steve
* Allow specparams as constants in expressions.
*
* Revision 1.25 2006/06/02 04:48:50 steve
* Make elaborate_expr methods aware of the width that the context
* requires of it. In the process, fix sizing of the width of unary
* minus is context determined sizes.
*
* Revision 1.24 2005/11/27 05:56:20 steve
* Handle bit select of parameter with ranges.
*
* Revision 1.23 2005/07/11 16:56:51 steve
* Remove NetVariable and ivl_variable_t structures.
*
* Revision 1.22 2005/05/24 01:44:28 steve
* Do sign extension of structuran nets.
*
* Revision 1.21 2005/04/24 23:44:02 steve
* Update DFF support to new data flow.
*
* Revision 1.20 2005/01/24 05:28:31 steve
* Remove the NetEBitSel and combine all bit/part select
* behavior into the NetESelect node and IVL_EX_SELECT
* ivl_target expression type.
*
* Revision 1.19 2004/03/07 20:04:11 steve
* MOre thorough use of elab_and_eval function.
*
* Revision 1.18 2003/09/19 03:30:05 steve
* Fix name search in elab_lval.
*
* Revision 1.17 2003/01/30 16:23:08 steve
* Spelling fixes.
*
* Revision 1.16 2002/08/31 03:48:50 steve
* Fix reverse bit ordered bit select in continuous assignment.
*
* Revision 1.15 2002/08/12 01:35:00 steve
* conditional ident string using autoconfig.
*
* Revision 1.14 2002/06/25 01:33:22 steve
* Cache calculated driven value.
*
* Revision 1.13 2002/06/24 01:49:39 steve
* Make link_drive_constant cache its results in
* the Nexus, to improve cprop performance.
*
* Revision 1.12 2001/02/15 06:59:36 steve
* FreeBSD port has a maintainer now.
*
* Revision 1.11 2001/02/10 20:29:39 steve
* In the context of range declarations, use elab_and_eval instead
* of the less robust eval_const methods.
*
* Revision 1.10 2000/11/20 00:58:40 steve
* Add support for supply nets (PR#17)
*
* Revision 1.9 2000/09/20 02:53:15 steve
* Correctly measure comples l-values of assignments.
*
* Revision 1.8 2000/06/25 19:59:42 steve
* Redesign Links to include the Nexus class that
* carries properties of the connected set of links.
*
* Revision 1.7 2000/05/14 17:55:04 steve
* Support initialization of FF Q value.
*/
#endif
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