#ifndef __PExpr_H #define __PExpr_H /* * Copyright (c) 1998-1999 Stephen Williams * * 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 */ #if !defined(WINNT) #ident "$Id: PExpr.h,v 1.9 1999/05/16 05:08:42 steve Exp $" #endif # include # include "netlist.h" # include "verinum.h" # include "LineInfo.h" class Design; class Module; class NetNet; class NetExpr; /* * The PExpr class hierarchy supports the description of * expressions. The parser can generate expression objects from the * source, possibly reducing things that it knows how to reduce. * * The elaborate_net method is used by structural elaboration to build * up a netlist interpretation of the expression. */ class PExpr : public LineInfo { public: virtual ~PExpr(); virtual void dump(ostream&) const; virtual NetNet* elaborate_net(Design*des, const string&path) const; virtual NetExpr*elaborate_expr(Design*des, const string&path) const; // This attempts to evaluate a constant expression, and return // a verinum as a result. If the expression cannot be // evaluated, return 0. virtual verinum* eval_const(const Design*des, const string&path) const; // This method returns true if that expression is the same as // this expression. This method is used for comparing // expressions that must be structurally "identical". virtual bool is_the_same(const PExpr*that) const; // Return true if this expression is a valid constant // expression. the Module pointer is needed to find parameter // identifiers and any other module specific interpretations // of expresions. virtual bool is_constant(Module*) const; }; ostream& operator << (ostream&, const PExpr&); class PEConcat : public PExpr { public: PEConcat(const svector&p) : parms_(p) { } virtual void dump(ostream&) const; virtual NetNet* elaborate_net(Design*des, const string&path) const; private: svectorparms_; }; class PEEvent : public PExpr { public: PEEvent(NetNEvent::Type t, PExpr*e) : type_(t), expr_(e) { } NetNEvent::Type type() const { return type_; } PExpr* expr() const { return expr_; } virtual void dump(ostream&) const; private: NetNEvent::Type type_; PExpr*expr_; }; class PEIdent : public PExpr { public: explicit PEIdent(const string&s) : text_(s), msb_(0), lsb_(0), idx_(0) { } virtual void dump(ostream&) const; virtual NetNet* elaborate_net(Design*des, const string&path) const; virtual NetExpr*elaborate_expr(Design*des, const string&path) const; virtual bool is_constant(Module*) const; verinum* eval_const(const Design*des, const string&path) const; // XXXX string name() const { return text_; } private: string text_; public: // Use these to support bit- and part-select operators. PExpr*msb_; PExpr*lsb_; // If this is a reference to a memory, this is the index // expression. PExpr*idx_; }; class PENumber : public PExpr { public: explicit PENumber(verinum*vp) : value_(vp) { assert(vp); } ~PENumber() { delete value_; } const verinum& value() const { return *value_; } virtual void dump(ostream&) const; virtual NetNet* elaborate_net(Design*des, const string&path) const; virtual NetExpr*elaborate_expr(Design*des, const string&path) const; virtual verinum* eval_const(const Design*des, const string&path) const; virtual bool is_the_same(const PExpr*that) const; virtual bool is_constant(Module*) const; private: verinum*const value_; }; class PEString : public PExpr { public: explicit PEString(const string&s) : text_(s) { } string value() const { return text_; } virtual void dump(ostream&) const; virtual NetExpr*elaborate_expr(Design*des, const string&path) const; virtual bool is_constant(Module*) const; private: const string text_; }; class PEUnary : public PExpr { public: explicit PEUnary(char op, PExpr*ex) : op_(op), expr_(ex) { } virtual void dump(ostream&out) const; virtual NetNet* elaborate_net(Design*des, const string&path) const; virtual NetExpr*elaborate_expr(Design*des, const string&path) const; private: char op_; PExpr*expr_; }; class PEBinary : public PExpr { public: explicit PEBinary(char op, PExpr*l, PExpr*r) : op_(op), left_(l), right_(r) { } virtual void dump(ostream&out) const; virtual NetNet* elaborate_net(Design*des, const string&path) const; virtual NetExpr*elaborate_expr(Design*des, const string&path) const; virtual verinum* eval_const(const Design*des, const string&path) const; private: char op_; PExpr*left_; PExpr*right_; }; /* * $Log: PExpr.h,v $ * Revision 1.9 1999/05/16 05:08:42 steve * Redo constant expression detection to happen * after parsing. * * Parse more operators and expressions. * * Revision 1.8 1999/05/10 00:16:57 steve * Parse and elaborate the concatenate operator * in structural contexts, Replace vector * and list with svector, evaluate * constant expressions with parameters, handle * memories as lvalues. * * Parse task declarations, integer types. * * Revision 1.7 1999/05/01 02:57:52 steve * Handle much more complex event expressions. * * Revision 1.6 1999/04/29 02:16:26 steve * Parse OR of event expressions. * * Revision 1.5 1999/04/19 01:59:36 steve * Add memories to the parse and elaboration phases. * * Revision 1.4 1998/11/11 00:01:51 steve * Check net ranges in declarations. * * Revision 1.3 1998/11/09 18:55:33 steve * Add procedural while loops, * Parse procedural for loops, * Add procedural wait statements, * Add constant nodes, * Add XNOR logic gate, * Make vvm output look a bit prettier. * * Revision 1.2 1998/11/07 17:05:05 steve * Handle procedural conditional, and some * of the conditional expressions. * * Elaborate signals and identifiers differently, * allowing the netlist to hold signal information. * * Revision 1.1 1998/11/03 23:28:54 steve * Introduce verilog to CVS. * */ #endif