xref: /netbsd-src/external/gpl3/gcc.old/dist/gcc/cp/cp-lang.c (revision 53b02e147d4ed531c0d2a5ca9b3e8026ba3e99b5)
1 /* Language-dependent hooks for C++.
2    Copyright (C) 2001-2019 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 
38 /* Lang hooks common to C++ and ObjC++ are declared in cp/cp-objcp-common.h;
39    consequently, there should be very few hooks below.  */
40 
41 #undef LANG_HOOKS_NAME
42 #define LANG_HOOKS_NAME "GNU C++"
43 #undef LANG_HOOKS_INIT
44 #define LANG_HOOKS_INIT cxx_init
45 #undef LANG_HOOKS_CLASSIFY_RECORD
46 #define LANG_HOOKS_CLASSIFY_RECORD cp_classify_record
47 #undef LANG_HOOKS_GENERIC_TYPE_P
48 #define LANG_HOOKS_GENERIC_TYPE_P class_tmpl_impl_spec_p
49 
50 #undef LANG_HOOKS_GET_INNERMOST_GENERIC_PARMS
51 #define LANG_HOOKS_GET_INNERMOST_GENERIC_PARMS \
52 	get_primary_template_innermost_parameters
53 #undef LANG_HOOKS_GET_INNERMOST_GENERIC_ARGS
54 #define LANG_HOOKS_GET_INNERMOST_GENERIC_ARGS \
55 	get_template_innermost_arguments_folded
56 #undef LANG_HOOKS_FUNCTION_PARAMETER_PACK_P
57 #define LANG_HOOKS_FUNCTION_PARAMETER_PACK_P \
58 	function_parameter_pack_p
59 #undef LANG_HOOKS_GET_ARGUMENT_PACK_ELEMS
60 #define LANG_HOOKS_GET_ARGUMENT_PACK_ELEMS \
61 	get_template_argument_pack_elems_folded
62 #undef LANG_HOOKS_GENERIC_GENERIC_PARAMETER_DECL_P
63 #define LANG_HOOKS_GENERIC_GENERIC_PARAMETER_DECL_P \
64 	template_template_parameter_p
65 #undef LANG_HOOKS_FUNCTION_PARM_EXPANDED_FROM_PACK_P
66 #define LANG_HOOKS_FUNCTION_PARM_EXPANDED_FROM_PACK_P \
67 	function_parameter_expanded_from_pack_p
68 #undef LANG_HOOKS_GET_GENERIC_FUNCTION_DECL
69 #define LANG_HOOKS_GET_GENERIC_FUNCTION_DECL get_function_template_decl
70 #undef LANG_HOOKS_DWARF_NAME
71 #define LANG_HOOKS_DWARF_NAME cxx_dwarf_name
72 #undef LANG_HOOKS_INIT_TS
73 #define LANG_HOOKS_INIT_TS cp_common_init_ts
74 #undef LANG_HOOKS_EH_PERSONALITY
75 #define LANG_HOOKS_EH_PERSONALITY cp_eh_personality
76 #undef LANG_HOOKS_EH_RUNTIME_TYPE
77 #define LANG_HOOKS_EH_RUNTIME_TYPE build_eh_type_type
78 #undef LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE
79 #define LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE cxx_enum_underlying_base_type
80 
81 #if CHECKING_P
82 #undef LANG_HOOKS_RUN_LANG_SELFTESTS
83 #define LANG_HOOKS_RUN_LANG_SELFTESTS selftest::run_cp_tests
84 #endif /* #if CHECKING_P */
85 
86 #undef LANG_HOOKS_GET_SUBSTRING_LOCATION
87 #define LANG_HOOKS_GET_SUBSTRING_LOCATION c_get_substring_location
88 
89 /* Each front end provides its own lang hook initializer.  */
90 struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;
91 
92 /* Lang hook routines common to C++ and ObjC++ appear in cp/cp-objcp-common.c;
93    there should be very few routines below.  */
94 
95 /* The following function does something real, but only in Objective-C++.  */
96 
97 tree
98 objcp_tsubst_copy_and_build (tree /*t*/,
99 			     tree /*args*/,
100 			     tsubst_flags_t /*complain*/,
101 			     tree /*in_decl*/,
102 			     bool /*function_p*/)
103 {
104   return NULL_TREE;
105 }
106 
107 static const char *
108 cxx_dwarf_name (tree t, int verbosity)
109 {
110   gcc_assert (DECL_P (t));
111 
112   if (DECL_NAME (t)
113       && (anon_aggrname_p (DECL_NAME (t)) || LAMBDA_TYPE_P (t)))
114     return NULL;
115   if (verbosity >= 2)
116     return decl_as_dwarf_string (t,
117                                  TFF_DECL_SPECIFIERS | TFF_UNQUALIFIED_NAME
118                                  | TFF_NO_OMIT_DEFAULT_TEMPLATE_ARGUMENTS);
119 
120   return lang_decl_dwarf_name (t, verbosity, false);
121 }
122 
123 static enum classify_record
124 cp_classify_record (tree type)
125 {
126   if (TYPE_LANG_SPECIFIC (type)
127       && CLASSTYPE_DECLARED_CLASS (type))
128     return RECORD_IS_CLASS;
129 
130   return RECORD_IS_STRUCT;
131 }
132 
133 static GTY(()) tree cp_eh_personality_decl;
134 
135 static tree
136 cp_eh_personality (void)
137 {
138   if (!cp_eh_personality_decl)
139     cp_eh_personality_decl = build_personality_function ("gxx");
140 
141   return cp_eh_personality_decl;
142 }
143 
144 /* This is a subroutine of fold_cplus_constants.  It returns TRUE if T
145    is a C++ specific constant that needs to be folded further before
146    being passed to the debug info emitter.  */
147 
148 static bool
149 template_arg_needs_folding (const_tree t)
150 {
151   /* For now only PTRMEM_CST nodes are to be folded further.  */
152   if (TREE_CODE (t) == PTRMEM_CST)
153     return true;
154   return false;
155 }
156 
157 /* Fold the elements of the TREE_VEC C which are C++ specific nodes
158    that would need folding so that they can be processed by the debug
159    info emitter. This is a subroutine of
160    get_template_innermost_arguments_folded and
161    get_template_argument_pack_elems_folded.  */
162 
163 static tree
164 fold_cplus_constants (const_tree c)
165 {
166   tree folded_elems, elems = CONST_CAST_TREE (c);
167   int vec_len, i;
168 
169   if (elems == NULL_TREE || elems == error_mark_node)
170     return elems;
171 
172   vec_len = TREE_VEC_LENGTH (elems);
173 
174   /* First check if there is at least one element that needs
175      folding. If there is none, we just return ELEMS. Otherwise create
176      and return a new tree vector that contains the folded versions of
177      ELEMS. This is to avoid allocating memory if we don't need
178      to.  */
179   for (i = 0; i < vec_len; ++i)
180     {
181       if (template_arg_needs_folding (TREE_VEC_ELT (elems, i)))
182 	break;
183     }
184   if (i == vec_len)
185     return elems;
186 
187   folded_elems = make_tree_vec (vec_len);
188   for (i = 0; i < vec_len; ++i)
189     {
190       tree elem = TREE_VEC_ELT (elems, i);
191       TREE_VEC_ELT (folded_elems, i) =
192 	(elem && !TYPE_P (elem)) ? cplus_expand_constant (elem) : elem;
193 
194     }
195   return folded_elems;
196 }
197 
198 /* The C++ implementation of the LANG_HOOKS_GET_INNERMOST_GENERIC_ARGS
199    hook. It returns the innermost template arguments of type T, and
200    makes sure those arguments are folded enough for the debug info
201    emitter.  */
202 
203 static tree
204 get_template_innermost_arguments_folded (const_tree t)
205 {
206   return fold_cplus_constants (get_template_innermost_arguments (t));
207 }
208 
209 static tree
210 get_template_argument_pack_elems_folded (const_tree t)
211 {
212   return fold_cplus_constants (get_template_argument_pack_elems (t));
213 }
214 
215 /* The C++ version of the enum_underlying_base_type langhook.
216    See also cp/semantics.c (finish_underlying_type).  */
217 
218 static
219 tree cxx_enum_underlying_base_type (const_tree type)
220 {
221   tree underlying_type = ENUM_UNDERLYING_TYPE (type);
222 
223   if (! ENUM_FIXED_UNDERLYING_TYPE_P (type))
224     underlying_type
225       = c_common_type_for_mode (TYPE_MODE (underlying_type),
226                                 TYPE_UNSIGNED (underlying_type));
227 
228   return underlying_type;
229 }
230 
231 #if CHECKING_P
232 
233 namespace selftest {
234 
235 /* Implementation of LANG_HOOKS_RUN_LANG_SELFTESTS for the C++ frontend.  */
236 
237 void
238 run_cp_tests (void)
239 {
240   /* Run selftests shared within the C family.  */
241   c_family_tests ();
242 
243   /* Additional C++-specific tests.  */
244   cp_pt_c_tests ();
245   cp_tree_c_tests ();
246 }
247 
248 } // namespace selftest
249 
250 #endif /* #if CHECKING_P */
251 
252 
253 #include "gt-cp-cp-lang.h"
254 #include "gtype-cp.h"
255