1/* Language-dependent hooks for C++.
2 Copyright (C) 2001-2024 Free Software Foundation, Inc.
3 Contributed by Alexandre Oliva <aoliva@redhat.com>
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify
8it under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 3, or (at your option)
10any later version.
11
12GCC is distributed in the hope that it will be useful,
13but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15GNU General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along 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
30enum c_language_kind c_language = clk_cxx;
31static const char * cxx_dwarf_name (tree t, int verbosity);
32static enum classify_record cp_classify_record (tree type);
33static tree cp_eh_personality (void);
34static tree get_template_innermost_arguments_folded (const_tree);
35static tree get_template_argument_pack_elems_folded (const_tree);
36static tree cxx_enum_underlying_base_type (const_tree);
37static tree *cxx_omp_get_decl_init (tree);
38static void cxx_omp_finish_decl_inits (void);
39static 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. */
108struct 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
115tree
116objcp_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
125void
126c_family_register_lang_features ()
127{
128 cp_register_features ();
129}
130
131static const char *
132cxx_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
146static enum classify_record
147cp_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
156static GTY(()) tree cp_eh_personality_decl;
157
158static tree
159cp_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
171static bool
172template_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
186static tree
187fold_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
226static tree
227get_template_innermost_arguments_folded (const_tree t)
228{
229 return fold_cplus_constants (c: get_template_innermost_arguments (t));
230}
231
232static tree
233get_template_argument_pack_elems_folded (const_tree t)
234{
235 return fold_cplus_constants (c: 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
241static
242tree 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
259static tree *
260cxx_omp_get_decl_init (tree decl)
261{
262 if (DECL_INITIAL (decl))
263 return &DECL_INITIAL (decl);
264
265 return hash_map_safe_get (h: dynamic_initializers, k: 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
272static void
273cxx_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
281static const char *
282cp_get_sarif_source_language (const char *)
283{
284 return "cplusplus";
285}
286
287#if CHECKING_P
288
289namespace selftest {
290
291/* Implementation of LANG_HOOKS_RUN_LANG_SELFTESTS for the C++ frontend. */
292
293void
294run_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"
311

source code of gcc/cp/cp-lang.cc