verilator/src/V3ParseSym.h

// -*- mode: C++; c-file-style: "cc-mode" -*-
//*************************************************************************
// DESCRIPTION: Verilator: Common header between parser and lex
//
// Code available from: http://www.veripool.org/verilator
//
//*************************************************************************
//
// Copyright 2009-2016 by Wilson Snyder.  This program is free software; you can
// redistribute it and/or modify it under the terms of either the GNU
// Lesser General Public License Version 3 or the Perl Artistic License
// Version 2.0.
//
// Verilator 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.
//
//*************************************************************************

#ifndef _V3PARSESYM_H_
#define _V3PARSESYM_H_ 1
#include "config_build.h"
#include "verilatedos.h"
#include "V3Error.h"
#include "V3FileLine.h"
#include "V3Global.h"
#include "V3SymTable.h"
#include <deque>

//######################################################################
// Symbol table for parsing

class V3ParseSym {
    // TYPES
    typedef vector<VSymEnt*>	SymStack;

private:
    // MEMBERS
    static int	s_anonNum;		// Number of next anonymous object (parser use only)
    VSymGraph	m_syms;			// Graph of symbol tree
    VSymEnt*	m_symTableNextId;	// Symbol table for next lexer lookup (parser use only)
    VSymEnt*	m_symCurrentp;		// Active symbol table for additions/lookups
    SymStack	m_sympStack;		// Stack of upper nodes with pending symbol tables

private:
    // METHODS
    static VSymEnt* getTable(AstNode* nodep) {
	if (!nodep->user4p()) nodep->v3fatalSrc("Current symtable not found");
	return nodep->user4p()->castSymEnt();
    }

public:
    VSymEnt* nextId() const { return m_symTableNextId; }
    VSymEnt* symCurrentp() const { return m_symCurrentp; }
    VSymEnt* symRootp() const { return m_syms.rootp(); }

    VSymEnt* findNewTable(AstNode* nodep) {
	if (!nodep->user4p()) {
	    VSymEnt* symsp = new VSymEnt(&m_syms, nodep);
	    nodep->user4p(symsp);
	}
	return getTable(nodep);
    }
    void nextId(AstNode* entp) {
	if (entp) {
	    UINFO(9,"symTableNextId under "<<entp<<"-"<<entp->type().ascii()<<endl);
	    m_symTableNextId = getTable(entp);
	}
	else {
	    UINFO(9,"symTableNextId under NULL"<<endl);
	    m_symTableNextId = NULL;
	}
    }
    void reinsert(AstNode* nodep, VSymEnt* parentp=NULL) {
	reinsert(nodep, parentp, nodep->name());
    }
    void reinsert(AstNode* nodep, VSymEnt* parentp, string name) {
	if (!parentp) parentp = symCurrentp();
	if (name == "") {  // New name with space in name so can't collide with users
	    name = string(" anon") + nodep->type().ascii() + cvtToStr(++s_anonNum);
	}
	parentp->reinsert(name, findNewTable(nodep));
    }
    void pushNew(AstNode* nodep) { pushNewUnder(nodep, NULL); }
    void pushNewUnder(AstNode* nodep, VSymEnt* parentp) {
	if (!parentp) parentp = symCurrentp();
	VSymEnt* symp = findNewTable(nodep);  // Will set user4p, which is how we connect table to node
	symp->fallbackp(parentp);
	reinsert(nodep, parentp);
	pushScope(symp);
    }
    void pushScope(VSymEnt* symp) {
	m_sympStack.push_back(symp);
	m_symCurrentp = symp;
    }
    void popScope(AstNode* nodep) {
	if (symCurrentp()->nodep() != nodep) {
	    if (debug()) { showUpward(); dump(cout,"-mism: "); }
	    nodep->v3fatalSrc("Symbols suggest ending "<<symCurrentp()->nodep()->prettyTypeName()
			      <<" but parser thinks ending "<<nodep->prettyTypeName());
	    return;
	}
	m_sympStack.pop_back();
	if (m_sympStack.empty()) { nodep->v3fatalSrc("symbol stack underflow"); return; }
	m_symCurrentp = m_sympStack.back();
    }
    void showUpward () {
	UINFO(1,"ParseSym Stack:\n");
	for (SymStack::reverse_iterator it=m_sympStack.rbegin(); it!=m_sympStack.rend(); ++it) {
	    VSymEnt* symp = *it;
	    UINFO(1,"\t"<<symp->nodep()<<endl);
	}
	UINFO(1,"ParseSym Current: "<<symCurrentp()->nodep()<<endl);
    }
    void dump(ostream& os, const string& indent="") {
	m_syms.dump(os,indent);
    }
    AstNode* findEntUpward (const string& name) {
	// Lookup the given string as an identifier, return type of the id, scanning upward
	return symCurrentp()->findIdFallback(name)->nodep();
    }
    void import(AstNode* packagep, const string& id_or_star) {
	// Import from package::id_or_star to this
	VSymEnt* symp = getTable(packagep);
	if (!symp) {  // Internal problem, because we earlier found pkg to label it an ID__aPACKAGE
	    packagep->v3fatalSrc("Import package not found");
	    return;
	}
	// Walk old sym table and reinsert into current table
	// We let V3LinkDot report the error instead of us
	symCurrentp()->importFromPackage(&m_syms, symp, id_or_star);
    }
public:
    // CREATORS
    explicit V3ParseSym(AstNetlist* rootp)
	: m_syms(rootp) {
	s_anonNum = 0;		// Number of next anonymous object
	pushScope(findNewTable(rootp));
	m_symTableNextId = NULL;
	m_symCurrentp = symCurrentp();
    }
    ~V3ParseSym() {}
};

#endif // Guard