symbol_table.h

/*
 * SPDX-FileCopyrightText: 2013 Barefoot Networks, Inc.
 * Copyright 2013-present Barefoot Networks, Inc.
 *
 * SPDX-License-Identifier: Apache-2.0
 */
 
/* -*-C++-*- */
 
#ifndef FRONTENDS_P4_SYMBOL_TABLE_H_
#define FRONTENDS_P4_SYMBOL_TABLE_H_
 
/* A very simple symbol table that recognizes types; necessary because
   the v1.2 grammar is ambiguous without type information */
 
#include <unordered_map>
#include <vector>
 
#include "ir/ir.h"
#include "lib/cstring.h"
#include "lib/source_file.h"
 
namespace P4::Util {
class NamedSymbol;
class Namespace;
 
// Maintains a high-level representation of the program structure
// built on the fly during parsing.  Used by the lexer to
// disambiguate identifiers.
class ProgramStructure final {
 private:
    bool debug;
    FILE *debugStream;
    Namespace *rootNamespace;
    Namespace *currentNamespace;
 
    struct PathContext {
        const NamedSymbol *previousSymbol;
        const Namespace *lookupContext;
        PathContext() : previousSymbol(nullptr), lookupContext(nullptr) {}
    } identifierContext;
 
    void push(Namespace *ns);
    NamedSymbol *lookup(const cstring identifier);
    void declare(NamedSymbol *symbol);
 
 public:
    enum class SymbolKind {
        Identifier,
        TemplateIdentifier,
        Type,
        TemplateType,
    };
 
    ProgramStructure();
 
    void setDebug(bool debug) { this->debug = debug; }
    void pushNamespace(SourceInfo info, bool allowDuplicates);
    void pushContainerType(IR::ID id, bool allowDuplicates);
    void declareType(IR::ID id);
    void declareObject(IR::ID id, cstring type);
    void markAsTemplate(IR::ID id);  // the symbol expects template args
 
    // the last namespace has been exited
    void pop();
    // Declares these types in the current scope
    void declareTypes(const IR::IndexedVector<IR::Type_Var> &typeVars);
    void declareParameters(const IR::IndexedVector<IR::Parameter> &params);
    SymbolKind lookupIdentifier(cstring identifier);
 
    void startAbsolutePath();
    void relativePathFromLastSymbol();
    void clearPath();
 
    void endParse();
 
    cstring toString() const;
    void clear();
};
 
}  // namespace P4::Util
#endif /* FRONTENDS_P4_SYMBOL_TABLE_H_ */