gcc/gcc-rich-location.h

   1 /* Declarations relating to class gcc_rich_location
   2    Copyright (C) 2014-2020 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef GCC_RICH_LOCATION_H
  21 #define GCC_RICH_LOCATION_H
  22
  23 /* A gcc_rich_location is libcpp's rich_location with additional
  24    helper methods for working with gcc's types.  */
  25 class gcc_rich_location : public rich_location
  26 {
  27  public:
  28   /* Constructors.  */
  29
  30   /* Constructing from a location.  */
  31   gcc_rich_location (location_t loc, const range_label *label = NULL)
  32   : rich_location (line_table, loc, label)
  33   {
  34   }
  35
  36   /* Methods for adding ranges via gcc entities.  */
  37   void
  38   add_expr (tree expr, range_label *label);
  39
  40   void
  41   maybe_add_expr (tree t, range_label *label);
  42
  43   void add_fixit_misspelled_id (location_t misspelled_token_loc,
  44                                 tree hint_id);
  45
  46   /* If LOC is within the spans of lines that will already be printed for
  47      this gcc_rich_location, then add it as a secondary location
  48      and return true.
  49
  50      Otherwise return false.
  51
  52      This allows for a diagnostic to compactly print secondary locations
  53      in one diagnostic when these are near enough the primary locations for
  54      diagnostics-show-locus.c to cope with them, and to fall back to
  55      printing them via a note otherwise e.g.:
  56
  57         gcc_rich_location richloc (primary_loc);
  58         bool added secondary = richloc.add_location_if_nearby (secondary_loc);
  59         error_at (&richloc, "main message");
  60         if (!added secondary)
  61           inform (secondary_loc, "message for secondary");
  62
  63      Implemented in diagnostic-show-locus.c.  */
  64
  65   bool add_location_if_nearby (location_t loc,
  66                                bool restrict_to_current_line_spans = true,
  67                                const range_label *label = NULL);
  68
  69   /* Add a fix-it hint suggesting the insertion of CONTENT before
  70      INSERTION_POINT.
  71
  72      Attempt to handle formatting: if INSERTION_POINT is the first thing on
  73      its line, and INDENT is sufficiently sane, then add CONTENT on its own
  74      line, using the indentation of INDENT.
  75      Otherwise, add CONTENT directly before INSERTION_POINT.
  76
  77      For example, adding "CONTENT;" with the closing brace as the insertion
  78      point and using "INDENT;" for indentation:
  79
  80        if ()
  81          {
  82            INDENT;
  83          }
  84
  85      would lead to:
  86
  87        if ()
  88          {
  89            INDENT;
  90            CONTENT;
  91          }
  92
  93      but adding it to:
  94
  95        if () {INDENT;}
  96
  97      would lead to:
  98
  99        if () {INDENT;CONTENT;}
 100   */
 101   void add_fixit_insert_formatted (const char *content,
 102                                    location_t insertion_point,
 103                                    location_t indent);
 104 };
 105
 106 /* Concrete subclass of libcpp's range_label.
 107    Simple implementation using a string literal.  */
 108
 109 class text_range_label : public range_label
 110 {
 111  public:
 112   text_range_label (const char *text) : m_text (text) {}
 113
 114   label_text get_text (unsigned /*range_idx*/) const FINAL OVERRIDE
 115   {
 116     return label_text::borrow (m_text);
 117   }
 118
 119  private:
 120   const char *m_text;
 121 };
 122
 123 /* Concrete subclass of libcpp's range_label for use in
 124    diagnostics involving mismatched types.
 125
 126    Each frontend that uses this should supply its own implementation.
 127
 128    Generate a label describing LABELLED_TYPE.  The frontend may use
 129    OTHER_TYPE where appropriate for highlighting the differences between
 130    the two types (analogous to C++'s use of %H and %I with
 131    template types).
 132
 133    Either or both of LABELLED_TYPE and OTHER_TYPE may be NULL_TREE.
 134    If LABELLED_TYPE is NULL_TREE, then there is no label.
 135
 136    For example, this rich_location could use two instances of
 137    range_label_for_type_mismatch:
 138
 139       printf ("arg0: %i  arg1: %s arg2: %i",
 140                                ^~
 141                                |
 142                                const char *
 143               100, 101, 102);
 144                    ~~~
 145                    |
 146                    int
 147
 148    (a) the label for "%s" with LABELLED_TYPE for "const char*" and
 149    (b) the label for "101" with LABELLED TYPE for "int"
 150    where each one uses the other's type as OTHER_TYPE.  */
 151
 152 class range_label_for_type_mismatch : public range_label
 153 {
 154  public:
 155   range_label_for_type_mismatch (tree labelled_type, tree other_type)
 156   : m_labelled_type (labelled_type), m_other_type (other_type)
 157   {
 158   }
 159
 160   label_text get_text (unsigned range_idx) const OVERRIDE;
 161
 162  protected:
 163   tree m_labelled_type;
 164   tree m_other_type;
 165 };
 166
 167 /* Subclass of range_label for labelling the type of EXPR when reporting
 168    a type mismatch between EXPR and OTHER_EXPR.
 169    Either or both of EXPR and OTHER_EXPR could be NULL.  */
 170
 171 class maybe_range_label_for_tree_type_mismatch : public range_label
 172 {
 173  public:
 174   maybe_range_label_for_tree_type_mismatch (tree expr, tree other_expr)
 175   : m_expr (expr), m_other_expr (other_expr)
 176   {
 177   }
 178
 179   label_text get_text (unsigned range_idx) const FINAL OVERRIDE;
 180
 181  private:
 182   tree m_expr;
 183   tree m_other_expr;
 184 };
 185
 186 class op_location_t;
 187
 188 /* A subclass of rich_location for showing problems with binary operations.
 189
 190    If enough location information is available, the ctor will make a
 191    3-location rich_location of the form:
 192
 193      arg_0 op arg_1
 194      ~~~~~ ^~ ~~~~~
 195        |        |
 196        |        arg1 type
 197        arg0 type
 198
 199    labelling the types of the arguments if SHOW_TYPES is true.
 200
 201    Otherwise, it will fall back to a 1-location rich_location using the
 202    compound location within LOC:
 203
 204      arg_0 op arg_1
 205      ~~~~~~^~~~~~~~
 206
 207    for which we can't label the types.  */
 208
 209 class binary_op_rich_location : public gcc_rich_location
 210 {
 211  public:
 212   binary_op_rich_location (const op_location_t &loc,
 213                            tree arg0, tree arg1,
 214                            bool show_types);
 215
 216  private:
 217   static bool use_operator_loc_p (const op_location_t &loc,
 218                                   tree arg0, tree arg1);
 219
 220   maybe_range_label_for_tree_type_mismatch m_label_for_arg0;
 221   maybe_range_label_for_tree_type_mismatch m_label_for_arg1;
 222 };
 223
 224 #endif /* GCC_RICH_LOCATION_H */