Line data    Source code

       1              : // Copyright (C) 2020-2026 Free Software Foundation, Inc.
       2              : 
       3              : // This file is part of GCC.
       4              : 
       5              : // GCC is free software; you can redistribute it and/or modify it under
       6              : // the terms of the GNU General Public License as published by the Free
       7              : // Software Foundation; either version 3, or (at your option) any later
       8              : // version.
       9              : 
      10              : // GCC is distributed in the hope that it will be useful, but WITHOUT ANY
      11              : // WARRANTY; without even the implied warranty of MERCHANTABILITY or
      12              : // FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
      13              : // for more details.
      14              : 
      15              : // You should have received a copy of the GNU General Public License
      16              : // along with GCC; see the file COPYING3.  If not see
      17              : // <http://www.gnu.org/licenses/>.
      18              : 
      19              : #include "rust-ast.h"
      20              : #include "rust-macro-expand.h"
      21              : #include "rust-macro.h"
      22              : 
      23              : namespace Rust {
      24              : class SubstituteCtx
      25              : {
      26              :   std::vector<std::unique_ptr<AST::Token>> &input;
      27              :   std::vector<std::unique_ptr<AST::Token>> &macro;
      28              :   std::map<std::string, MatchedFragmentContainer *> &fragments;
      29              :   AST::MacroRulesDefinition &definition;
      30              :   // Macro invocation location
      31              :   location_t origin;
      32              : 
      33              :   /**
      34              :    * Find the repetition amount to use when expanding a repetition, and
      35              :    * check that all fragments used respect that repetition amount
      36              :    *
      37              :    * @param pattern_start Start of the repetition pattern
      38              :    * @param pattern_end End of the repetition pattern
      39              :    * @param repeat_amount Reference to fill with the matched repetition amount
      40              :    */
      41              :   bool check_repetition_amount (size_t pattern_start, size_t pattern_end,
      42              :                                 size_t &repeat_amount);
      43              : 
      44              : public:
      45         6529 :   SubstituteCtx (std::vector<std::unique_ptr<AST::Token>> &input,
      46              :                  std::vector<std::unique_ptr<AST::Token>> &macro,
      47              :                  std::map<std::string, MatchedFragmentContainer *> &fragments,
      48              :                  AST::MacroRulesDefinition &definition, location_t origin)
      49         6529 :     : input (input), macro (macro), fragments (fragments),
      50         6529 :       definition (definition), origin (origin)
      51              :   {}
      52              : 
      53              :   /**
      54              :    * Special-case the $crate metavar to expand to the name of the crate in which
      55              :    * the macro was defined.
      56              :    *
      57              :    * https://doc.rust-lang.org/reference/macros-by-example.html#r-macro.decl.hygiene.crate
      58              :    *
      59              :    *
      60              :    * @param expanded Reference to a vector upon which expanded tokens will be
      61              :    * pushed
      62              :    *
      63              :    * @return True if the substitution succeeded
      64              :    */
      65              :   bool
      66              :   substitute_dollar_crate (std::vector<std::unique_ptr<AST::Token>> &expanded);
      67              : 
      68              :   /**
      69              :    * Substitute a metavariable by its given fragment in a transcribing context,
      70              :    * i.e. replacing $var with the associated fragment.
      71              :    *
      72              :    * @param metavar Metavariable to try and replace
      73              :    * @param expanded Reference to a vector upon which expanded tokens will be
      74              :    * pushed
      75              :    *
      76              :    * @return True if the substitution succeeded
      77              :    */
      78              :   bool substitute_metavar (std::unique_ptr<AST::Token> &metavar,
      79              :                            std::vector<std::unique_ptr<AST::Token>> &expanded);
      80              : 
      81              :   /**
      82              :    * Substitute a macro repetition by its given fragments
      83              :    *
      84              :    * @param pattern_start Start index of the pattern tokens
      85              :    * @param pattern_end End index of the patterns tokens
      86              :    * @param separator Optional separator to include when expanding tokens
      87              :    *
      88              :    * @return A vector containing the repeated pattern
      89              :    */
      90              :   std::vector<std::unique_ptr<AST::Token>>
      91              :   substitute_repetition (size_t pattern_start, size_t pattern_end,
      92              :                          std::unique_ptr<AST::Token> separator);
      93              : 
      94              :   /**
      95              :    * Substitute a given token by its appropriate representation
      96              :    *
      97              :    * @param token_idx Current token to try and substitute
      98              :    *
      99              :    * @return A token containing the associated fragment expanded into tokens if
     100              :    * any, or the cloned token if no fragment was associated, as well as the
     101              :    * amount of tokens that should be skipped before the next invocation. Since
     102              :    * this function may consume more than just one token, it is important to skip
     103              :    * ahead of the input to avoid mis-substitutions
     104              :    */
     105              :   std::pair<std::vector<std::unique_ptr<AST::Token>>, size_t>
     106              :   substitute_token (size_t token_idx);
     107              : 
     108              :   /**
     109              :    * Substitute all tokens by their appropriate representation
     110              :    *
     111              :    * @return A vector containing the substituted tokens
     112              :    */
     113              :   std::vector<std::unique_ptr<AST::Token>> substitute_tokens ();
     114              : };
     115              : } // namespace Rust