gcc/gcc-rich-location.h

/* Declarations relating to class gcc_rich_location
   Copyright (C) 2014-2019 Free Software Foundation, Inc.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.

GCC 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 GCC; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  */

#ifndef GCC_RICH_LOCATION_H
#define GCC_RICH_LOCATION_H

/* A gcc_rich_location is libcpp's rich_location with additional
   helper methods for working with gcc's types.  */
class gcc_rich_location : public rich_location
{
 public:
  /* Constructors.  */

  /* Constructing from a location.  */
  gcc_rich_location (location_t loc, const range_label *label = NULL)
  : rich_location (line_table, loc, label)
  {
  }

  /* Methods for adding ranges via gcc entities.  */
  void
  add_expr (tree expr, range_label *label);

  void
  maybe_add_expr (tree t, range_label *label);

  void add_fixit_misspelled_id (location_t misspelled_token_loc,
				tree hint_id);

  /* If LOC is within the spans of lines that will already be printed for
     this gcc_rich_location, then add it as a secondary location
     and return true.

     Otherwise return false.

     This allows for a diagnostic to compactly print secondary locations
     in one diagnostic when these are near enough the primary locations for
     diagnostics-show-locus.c to cope with them, and to fall back to
     printing them via a note otherwise e.g.:

	gcc_rich_location richloc (primary_loc);
	bool added secondary = richloc.add_location_if_nearby (secondary_loc);
	error_at (&richloc, "main message");
	if (!added secondary)
	  inform (secondary_loc, "message for secondary");

     Implemented in diagnostic-show-locus.c.  */

  bool add_location_if_nearby (location_t loc);

  /* Add a fix-it hint suggesting the insertion of CONTENT before
     INSERTION_POINT.

     Attempt to handle formatting: if INSERTION_POINT is the first thing on
     its line, and INDENT is sufficiently sane, then add CONTENT on its own
     line, using the indentation of INDENT.
     Otherwise, add CONTENT directly before INSERTION_POINT.

     For example, adding "CONTENT;" with the closing brace as the insertion
     point and using "INDENT;" for indentation:

       if ()
         {
           INDENT;
         }

     would lead to:

       if ()
         {
           INDENT;
           CONTENT;
         }

     but adding it to:

       if () {INDENT;}

     would lead to:

       if () {INDENT;CONTENT;}
  */
  void add_fixit_insert_formatted (const char *content,
				   location_t insertion_point,
				   location_t indent);
};

/* Concrete subclass of libcpp's range_label.
   Simple implementation using a string literal.  */

class text_range_label : public range_label
{
 public:
  text_range_label (const char *text) : m_text (text) {}

  label_text get_text (unsigned /*range_idx*/) const FINAL OVERRIDE
  {
    return label_text (const_cast <char *> (m_text), false);
  }

 private:
  const char *m_text;
};

/* Concrete subclass of libcpp's range_label for use in
   diagnostics involving mismatched types.

   Each frontend that uses this should supply its own implementation.

   Generate a label describing LABELLED_TYPE.  The frontend may use
   OTHER_TYPE where appropriate for highlighting the differences between
   the two types (analogous to C++'s use of %H and %I with
   template types).

   Either or both of LABELLED_TYPE and OTHER_TYPE may be NULL_TREE.
   If LABELLED_TYPE is NULL_TREE, then there is no label.

   For example, this rich_location could use two instances of
   range_label_for_type_mismatch:

      printf ("arg0: %i  arg1: %s arg2: %i",
                               ^~
                               |
                               const char *
              100, 101, 102);
                   ~~~
                   |
                   int

   (a) the label for "%s" with LABELLED_TYPE for "const char*" and
   (b) the label for "101" with LABELLED TYPE for "int"
   where each one uses the other's type as OTHER_TYPE.  */

class range_label_for_type_mismatch : public range_label
{
 public:
  range_label_for_type_mismatch (tree labelled_type, tree other_type)
  : m_labelled_type (labelled_type), m_other_type (other_type)
  {
  }

  label_text get_text (unsigned range_idx) const OVERRIDE;

 protected:
  tree m_labelled_type;
  tree m_other_type;
};

/* Subclass of range_label for labelling the type of EXPR when reporting
   a type mismatch between EXPR and OTHER_EXPR.
   Either or both of EXPR and OTHER_EXPR could be NULL.  */

class maybe_range_label_for_tree_type_mismatch : public range_label
{
 public:
  maybe_range_label_for_tree_type_mismatch (tree expr, tree other_expr)
  : m_expr (expr), m_other_expr (other_expr)
  {
  }

  label_text get_text (unsigned range_idx) const FINAL OVERRIDE;

 private:
  tree m_expr;
  tree m_other_expr;
};

struct op_location_t;

/* A subclass of rich_location for showing problems with binary operations.

   If enough location information is available, the ctor will make a
   3-location rich_location of the form:

     arg_0 op arg_1
     ~~~~~ ^~ ~~~~~
       |        |
       |        arg1 type
       arg0 type

   labelling the types of the arguments if SHOW_TYPES is true.

   Otherwise, it will fall back to a 1-location rich_location using the
   compound location within LOC:

     arg_0 op arg_1
     ~~~~~~^~~~~~~~

   for which we can't label the types.  */

class binary_op_rich_location : public gcc_rich_location
{
 public:
  binary_op_rich_location (const op_location_t &loc,
			   tree arg0, tree arg1,
			   bool show_types);

 private:
  static bool use_operator_loc_p (const op_location_t &loc,
				  tree arg0, tree arg1);

  maybe_range_label_for_tree_type_mismatch m_label_for_arg0;
  maybe_range_label_for_tree_type_mismatch m_label_for_arg1;
};

#endif /* GCC_RICH_LOCATION_H */