gcc/cp/cp-lang.cc

   1 /* Language-dependent hooks for C++.
   2    Copyright (C) 2001-2024 Free Software Foundation, Inc.
   3    Contributed by Alexandre Oliva  <aoliva@redhat.com>
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #include "config.h"
  22 #include "system.h"
  23 #include "coretypes.h"
  24 #include "cp-tree.h"
  25 #include "stor-layout.h"
  26 #include "langhooks.h"
  27 #include "langhooks-def.h"
  28 #include "cp-objcp-common.h"
  29
  30 enum c_language_kind c_language = clk_cxx;
  31 static const char * cxx_dwarf_name (tree t, int verbosity);
  32 static enum classify_record cp_classify_record (tree type);
  33 static tree cp_eh_personality (void);
  34 static tree get_template_innermost_arguments_folded (const_tree);
  35 static tree get_template_argument_pack_elems_folded (const_tree);
  36 static tree cxx_enum_underlying_base_type (const_tree);
  37 static tree *cxx_omp_get_decl_init (tree);
  38 static void cxx_omp_finish_decl_inits (void);
  39 static const char *cp_get_sarif_source_language (const char *);
  40
  41 /* Lang hooks common to C++ and ObjC++ are declared in cp/cp-objcp-common.h;
  42    consequently, there should be very few hooks below.  */
  43
  44 #undef LANG_HOOKS_NAME
  45 #define LANG_HOOKS_NAME "GNU C++"
  46 #undef LANG_HOOKS_INIT
  47 #define LANG_HOOKS_INIT cxx_init
  48 #undef LANG_HOOKS_CLASSIFY_RECORD
  49 #define LANG_HOOKS_CLASSIFY_RECORD cp_classify_record
  50 #undef LANG_HOOKS_GENERIC_TYPE_P
  51 #define LANG_HOOKS_GENERIC_TYPE_P class_tmpl_impl_spec_p
  52
  53 #undef LANG_HOOKS_GET_INNERMOST_GENERIC_PARMS
  54 #define LANG_HOOKS_GET_INNERMOST_GENERIC_PARMS \
  55         get_primary_template_innermost_parameters
  56 #undef LANG_HOOKS_GET_INNERMOST_GENERIC_ARGS
  57 #define LANG_HOOKS_GET_INNERMOST_GENERIC_ARGS \
  58         get_template_innermost_arguments_folded
  59 #undef LANG_HOOKS_FUNCTION_PARAMETER_PACK_P
  60 #define LANG_HOOKS_FUNCTION_PARAMETER_PACK_P \
  61         function_parameter_pack_p
  62 #undef LANG_HOOKS_GET_ARGUMENT_PACK_ELEMS
  63 #define LANG_HOOKS_GET_ARGUMENT_PACK_ELEMS \
  64         get_template_argument_pack_elems_folded
  65 #undef LANG_HOOKS_GENERIC_GENERIC_PARAMETER_DECL_P
  66 #define LANG_HOOKS_GENERIC_GENERIC_PARAMETER_DECL_P \
  67         template_template_parameter_p
  68 #undef LANG_HOOKS_FUNCTION_PARM_EXPANDED_FROM_PACK_P
  69 #define LANG_HOOKS_FUNCTION_PARM_EXPANDED_FROM_PACK_P \
  70         function_parameter_expanded_from_pack_p
  71 #undef LANG_HOOKS_GET_GENERIC_FUNCTION_DECL
  72 #define LANG_HOOKS_GET_GENERIC_FUNCTION_DECL get_function_template_decl
  73 #undef LANG_HOOKS_DWARF_NAME
  74 #define LANG_HOOKS_DWARF_NAME cxx_dwarf_name
  75 #undef LANG_HOOKS_INIT_TS
  76 #define LANG_HOOKS_INIT_TS cp_common_init_ts
  77 #undef LANG_HOOKS_EH_PERSONALITY
  78 #define LANG_HOOKS_EH_PERSONALITY cp_eh_personality
  79 #undef LANG_HOOKS_EH_RUNTIME_TYPE
  80 #define LANG_HOOKS_EH_RUNTIME_TYPE build_eh_type_type
  81 #undef LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE
  82 #define LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE cxx_enum_underlying_base_type
  83 #undef LANG_HOOKS_PREPROCESS_MAIN_FILE
  84 #define LANG_HOOKS_PREPROCESS_MAIN_FILE module_begin_main_file
  85 #undef LANG_HOOKS_PREPROCESS_OPTIONS
  86 #define LANG_HOOKS_PREPROCESS_OPTIONS module_preprocess_options
  87 #undef LANG_HOOKS_PREPROCESS_TOKEN
  88 #define LANG_HOOKS_PREPROCESS_TOKEN module_token_pre
  89
  90 #if CHECKING_P
  91 #undef LANG_HOOKS_RUN_LANG_SELFTESTS
  92 #define LANG_HOOKS_RUN_LANG_SELFTESTS selftest::run_cp_tests
  93 #endif /* #if CHECKING_P */
  94
  95 #undef LANG_HOOKS_GET_SUBSTRING_LOCATION
  96 #define LANG_HOOKS_GET_SUBSTRING_LOCATION c_get_substring_location
  97
  98 #undef LANG_HOOKS_OMP_GET_DECL_INIT
  99 #define LANG_HOOKS_OMP_GET_DECL_INIT cxx_omp_get_decl_init
 100
 101 #undef LANG_HOOKS_OMP_FINISH_DECL_INITS
 102 #define LANG_HOOKS_OMP_FINISH_DECL_INITS cxx_omp_finish_decl_inits
 103
 104 #undef LANG_HOOKS_GET_SARIF_SOURCE_LANGUAGE
 105 #define LANG_HOOKS_GET_SARIF_SOURCE_LANGUAGE cp_get_sarif_source_language
 106
 107 /* Each front end provides its own lang hook initializer.  */
 108 struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;
 109
 110 /* Lang hook routines common to C++ and ObjC++ appear in cp/cp-objcp-common.cc;
 111    there should be very few routines below.  */
 112
 113 /* The following function does something real, but only in Objective-C++.  */
 114
 115 tree
 116 objcp_tsubst_expr (tree /*t*/, tree /*args*/, tsubst_flags_t /*complain*/,
 117                    tree /*in_decl*/)
 118 {
 119   return NULL_TREE;
 120 }
 121
 122 /* Implement c-family hook to add language-specific features
 123    for __has_{feature,extension}.  */
 124
 125 void
 126 c_family_register_lang_features ()
 127 {
 128   cp_register_features ();
 129 }
 130
 131 static const char *
 132 cxx_dwarf_name (tree t, int verbosity)
 133 {
 134   gcc_assert (DECL_P (t));
 135
 136   if (DECL_NAME (t) && IDENTIFIER_ANON_P (DECL_NAME (t)))
 137     return NULL;
 138   if (verbosity >= 2)
 139     return decl_as_dwarf_string (t,
 140                                  TFF_DECL_SPECIFIERS | TFF_UNQUALIFIED_NAME
 141                                  | TFF_NO_OMIT_DEFAULT_TEMPLATE_ARGUMENTS);
 142
 143   return lang_decl_dwarf_name (t, verbosity, false);
 144 }
 145
 146 static enum classify_record
 147 cp_classify_record (tree type)
 148 {
 149   if (TYPE_LANG_SPECIFIC (type)
 150       && CLASSTYPE_DECLARED_CLASS (type))
 151     return RECORD_IS_CLASS;
 152
 153   return RECORD_IS_STRUCT;
 154 }
 155
 156 static GTY(()) tree cp_eh_personality_decl;
 157
 158 static tree
 159 cp_eh_personality (void)
 160 {
 161   if (!cp_eh_personality_decl)
 162     cp_eh_personality_decl = build_personality_function ("gxx");
 163
 164   return cp_eh_personality_decl;
 165 }
 166
 167 /* This is a subroutine of fold_cplus_constants.  It returns TRUE if T
 168    is a C++ specific constant that needs to be folded further before
 169    being passed to the debug info emitter.  */
 170
 171 static bool
 172 template_arg_needs_folding (const_tree t)
 173 {
 174   /* For now only PTRMEM_CST nodes are to be folded further.  */
 175   if (TREE_CODE (t) == PTRMEM_CST)
 176     return true;
 177   return false;
 178 }
 179
 180 /* Fold the elements of the TREE_VEC C which are C++ specific nodes
 181    that would need folding so that they can be processed by the debug
 182    info emitter. This is a subroutine of
 183    get_template_innermost_arguments_folded and
 184    get_template_argument_pack_elems_folded.  */
 185
 186 static tree
 187 fold_cplus_constants (const_tree c)
 188 {
 189   tree folded_elems, elems = CONST_CAST_TREE (c);
 190   int vec_len, i;
 191
 192   if (elems == NULL_TREE || elems == error_mark_node)
 193     return elems;
 194
 195   vec_len = TREE_VEC_LENGTH (elems);
 196
 197   /* First check if there is at least one element that needs
 198      folding. If there is none, we just return ELEMS. Otherwise create
 199      and return a new tree vector that contains the folded versions of
 200      ELEMS. This is to avoid allocating memory if we don't need
 201      to.  */
 202   for (i = 0; i < vec_len; ++i)
 203     {
 204       if (template_arg_needs_folding (TREE_VEC_ELT (elems, i)))
 205         break;
 206     }
 207   if (i == vec_len)
 208     return elems;
 209
 210   folded_elems = make_tree_vec (vec_len);
 211   for (i = 0; i < vec_len; ++i)
 212     {
 213       tree elem = TREE_VEC_ELT (elems, i);
 214       TREE_VEC_ELT (folded_elems, i) =
 215         (elem && !TYPE_P (elem)) ? cplus_expand_constant (elem) : elem;
 216
 217     }
 218   return folded_elems;
 219 }
 220
 221 /* The C++ implementation of the LANG_HOOKS_GET_INNERMOST_GENERIC_ARGS
 222    hook. It returns the innermost template arguments of type T, and
 223    makes sure those arguments are folded enough for the debug info
 224    emitter.  */
 225
 226 static tree
 227 get_template_innermost_arguments_folded (const_tree t)
 228 {
 229   return fold_cplus_constants (get_template_innermost_arguments (t));
 230 }
 231
 232 static tree
 233 get_template_argument_pack_elems_folded (const_tree t)
 234 {
 235   return fold_cplus_constants (get_template_argument_pack_elems (t));
 236 }
 237
 238 /* The C++ version of the enum_underlying_base_type langhook.
 239    See also cp/semantics.cc (finish_underlying_type).  */
 240
 241 static
 242 tree cxx_enum_underlying_base_type (const_tree type)
 243 {
 244   tree underlying_type = ENUM_UNDERLYING_TYPE (type);
 245
 246   if (! ENUM_FIXED_UNDERLYING_TYPE_P (type))
 247     underlying_type
 248       = c_common_type_for_mode (TYPE_MODE (underlying_type),
 249                                 TYPE_UNSIGNED (underlying_type));
 250
 251   return underlying_type;
 252 }
 253
 254 /* The C++ version of the omp_get_decl_init langhook returns the static
 255    initializer for a variable declaration if present, otherwise it
 256    tries to find and return the dynamic initializer.  If not present,
 257    it returns NULL.  */
 258
 259 static tree *
 260 cxx_omp_get_decl_init (tree decl)
 261 {
 262   if (DECL_INITIAL (decl))
 263     return &DECL_INITIAL (decl);
 264
 265   return hash_map_safe_get (dynamic_initializers, decl);
 266 }
 267
 268 /* The C++ version of the omp_finish_decl_inits langhook allows GC to
 269    reclaim the memory used by the hash-map used to hold dynamic initializer
 270    information.  */
 271
 272 static void
 273 cxx_omp_finish_decl_inits (void)
 274 {
 275   dynamic_initializers = NULL;
 276 }
 277
 278 /* Get a value for the SARIF v2.1.0 "artifact.sourceLanguage" property,
 279    based on the list in SARIF v2.1.0 Appendix J.  */
 280
 281 static const char *
 282 cp_get_sarif_source_language (const char *)
 283 {
 284   return "cplusplus";
 285 }
 286
 287 #if CHECKING_P
 288
 289 namespace selftest {
 290
 291 /* Implementation of LANG_HOOKS_RUN_LANG_SELFTESTS for the C++ frontend.  */
 292
 293 void
 294 run_cp_tests (void)
 295 {
 296   /* Run selftests shared within the C family.  */
 297   c_family_tests ();
 298
 299   /* Additional C++-specific tests.  */
 300   cp_pt_cc_tests ();
 301   cp_tree_cc_tests ();
 302 }
 303
 304 } // namespace selftest
 305
 306 #endif /* #if CHECKING_P */
 307
 308
 309 #include "gt-cp-cp-lang.h"
 310 #include "gtype-cp.h"