gcc/cp/cp-lang.c

   1 /* Language-dependent hooks for C++.
   2    Copyright (C) 2001-2015 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 "tm.h"
  25 #include "hash-set.h"
  26 #include "vec.h"
  27 #include "input.h"
  28 #include "alias.h"
  29 #include "symtab.h"
  30 #include "inchash.h"
  31 #include "tree.h"
  32 #include "stor-layout.h"
  33 #include "cp-tree.h"
  34 #include "c-family/c-common.h"
  35 #include "langhooks.h"
  36 #include "langhooks-def.h"
  37 #include "debug.h"
  38 #include "cp-objcp-common.h"
  39 #include "hashtab.h"
  40 #include "target.h"
  41 #include "parser.h"
  42
  43 enum c_language_kind c_language = clk_cxx;
  44 static void cp_init_ts (void);
  45 static const char * cxx_dwarf_name (tree t, int verbosity);
  46 static enum classify_record cp_classify_record (tree type);
  47 static tree cp_eh_personality (void);
  48 static tree get_template_innermost_arguments_folded (const_tree);
  49 static tree get_template_argument_pack_elems_folded (const_tree);
  50 static tree cxx_enum_underlying_base_type (const_tree);
  51
  52 /* Lang hooks common to C++ and ObjC++ are declared in cp/cp-objcp-common.h;
  53    consequently, there should be very few hooks below.  */
  54
  55 #undef LANG_HOOKS_NAME
  56 #define LANG_HOOKS_NAME "GNU C++"
  57 #undef LANG_HOOKS_INIT
  58 #define LANG_HOOKS_INIT cxx_init
  59 #undef LANG_HOOKS_CLASSIFY_RECORD
  60 #define LANG_HOOKS_CLASSIFY_RECORD cp_classify_record
  61 #undef LANG_HOOKS_GENERIC_TYPE_P
  62 #define LANG_HOOKS_GENERIC_TYPE_P class_tmpl_impl_spec_p
  63
  64 #undef LANG_HOOKS_GET_INNERMOST_GENERIC_PARMS
  65 #define LANG_HOOKS_GET_INNERMOST_GENERIC_PARMS \
  66         get_primary_template_innermost_parameters
  67 #undef LANG_HOOKS_GET_INNERMOST_GENERIC_ARGS
  68 #define LANG_HOOKS_GET_INNERMOST_GENERIC_ARGS \
  69         get_template_innermost_arguments_folded
  70 #undef LANG_HOOKS_FUNCTION_PARAMETER_PACK_P
  71 #define LANG_HOOKS_FUNCTION_PARAMETER_PACK_P \
  72         function_parameter_pack_p
  73 #undef LANG_HOOKS_GET_ARGUMENT_PACK_ELEMS
  74 #define LANG_HOOKS_GET_ARGUMENT_PACK_ELEMS \
  75         get_template_argument_pack_elems_folded
  76 #undef LANG_HOOKS_GENERIC_GENERIC_PARAMETER_DECL_P
  77 #define LANG_HOOKS_GENERIC_GENERIC_PARAMETER_DECL_P \
  78         template_template_parameter_p
  79 #undef LANG_HOOKS_FUNCTION_PARM_EXPANDED_FROM_PACK_P
  80 #define LANG_HOOKS_FUNCTION_PARM_EXPANDED_FROM_PACK_P \
  81         function_parameter_expanded_from_pack_p
  82 #undef LANG_HOOKS_GET_GENERIC_FUNCTION_DECL
  83 #define LANG_HOOKS_GET_GENERIC_FUNCTION_DECL get_function_template_decl
  84 #undef LANG_HOOKS_DWARF_NAME
  85 #define LANG_HOOKS_DWARF_NAME cxx_dwarf_name
  86 #undef LANG_HOOKS_INIT_TS
  87 #define LANG_HOOKS_INIT_TS cp_init_ts
  88 #undef LANG_HOOKS_EH_PERSONALITY
  89 #define LANG_HOOKS_EH_PERSONALITY cp_eh_personality
  90 #undef LANG_HOOKS_EH_RUNTIME_TYPE
  91 #define LANG_HOOKS_EH_RUNTIME_TYPE build_eh_type_type
  92 #undef LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE
  93 #define LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE cxx_enum_underlying_base_type
  94
  95 /* Each front end provides its own lang hook initializer.  */
  96 struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;
  97
  98 /* Lang hook routines common to C++ and ObjC++ appear in cp/cp-objcp-common.c;
  99    there should be very few routines below.  */
 100
 101 /* The following function does something real, but only in Objective-C++.  */
 102
 103 tree
 104 objcp_tsubst_copy_and_build (tree /*t*/,
 105                              tree /*args*/,
 106                              tsubst_flags_t /*complain*/,
 107                              tree /*in_decl*/,
 108                              bool /*function_p*/)
 109 {
 110   return NULL_TREE;
 111 }
 112
 113 static void
 114 cp_init_ts (void)
 115 {
 116   cp_common_init_ts ();
 117
 118   init_shadowed_var_for_decl ();
 119 }
 120
 121 static const char *
 122 cxx_dwarf_name (tree t, int verbosity)
 123 {
 124   gcc_assert (DECL_P (t));
 125
 126   if (DECL_NAME (t)
 127       && (ANON_AGGRNAME_P (DECL_NAME (t)) || LAMBDA_TYPE_P (t)))
 128     return NULL;
 129   if (verbosity >= 2)
 130     return decl_as_dwarf_string (t,
 131                                  TFF_DECL_SPECIFIERS | TFF_UNQUALIFIED_NAME
 132                                  | TFF_NO_OMIT_DEFAULT_TEMPLATE_ARGUMENTS);
 133
 134   return lang_decl_dwarf_name (t, verbosity, false);
 135 }
 136
 137 static enum classify_record
 138 cp_classify_record (tree type)
 139 {
 140   if (TYPE_LANG_SPECIFIC (type)
 141       && CLASSTYPE_DECLARED_CLASS (type))
 142     return RECORD_IS_CLASS;
 143
 144   return RECORD_IS_STRUCT;
 145 }
 146
 147 static GTY(()) tree cp_eh_personality_decl;
 148
 149 static tree
 150 cp_eh_personality (void)
 151 {
 152   if (!cp_eh_personality_decl)
 153     {
 154       const char *lang = (pragma_java_exceptions ? "gcj" : "gxx");
 155       cp_eh_personality_decl = build_personality_function (lang);
 156     }
 157
 158   return cp_eh_personality_decl;
 159 }
 160
 161 /* This is a subroutine of fold_cplus_constants.  It returns TRUE if T
 162    is a C++ specific constant that needs to be folded further before
 163    being passed to the debug info emitter.  */
 164
 165 static bool
 166 template_arg_needs_folding (const_tree t)
 167 {
 168   /* For now only PTRMEM_CST nodes are to be folded further.  */
 169   if (TREE_CODE (t) == PTRMEM_CST)
 170     return true;
 171   return false;
 172 }
 173
 174 /* Fold the elements of the TREE_VEC C which are C++ specific nodes
 175    that would need folding so that they can be processed by the debug
 176    info emitter. This is a subroutine of
 177    get_template_innermost_arguments_folded and
 178    get_template_argument_pack_elems_folded.  */
 179
 180 static tree
 181 fold_cplus_constants (const_tree c)
 182 {
 183   tree folded_elems, elems = CONST_CAST_TREE (c);
 184   int vec_len, i;
 185
 186   if (elems == NULL_TREE || elems == error_mark_node)
 187     return elems;
 188
 189   vec_len = TREE_VEC_LENGTH (elems);
 190
 191   /* First check if there is at least one element that needs
 192      folding. If there is none, we just return ELEMS. Otherwise create
 193      and return a new tree vector that contains the folded versions of
 194      ELEMS. This is to avoid allocating memory if we don't need
 195      to.  */
 196   for (i = 0; i < vec_len; ++i)
 197     {
 198       if (template_arg_needs_folding (TREE_VEC_ELT (elems, i)))
 199         break;
 200     }
 201   if (i == vec_len)
 202     return elems;
 203
 204   folded_elems = make_tree_vec (vec_len);
 205   for (i = 0; i < vec_len; ++i)
 206     {
 207       tree elem = TREE_VEC_ELT (elems, i);
 208       TREE_VEC_ELT (folded_elems, i) =
 209         (elem && !TYPE_P (elem)) ? cplus_expand_constant (elem) : elem;
 210
 211     }
 212   return folded_elems;
 213 }
 214
 215 /* The C++ implementation of the LANG_HOOKS_GET_INNERMOST_GENERIC_ARGS
 216    hook. It returns the innermost template arguments of type T, and
 217    makes sure those arguments are folded enough for the debug info
 218    emitter.  */
 219
 220 static tree
 221 get_template_innermost_arguments_folded (const_tree t)
 222 {
 223   return fold_cplus_constants (get_template_innermost_arguments (t));
 224 }
 225
 226 static tree
 227 get_template_argument_pack_elems_folded (const_tree t)
 228 {
 229   return fold_cplus_constants (get_template_argument_pack_elems (t));
 230 }
 231
 232 /* The C++ version of the enum_underlying_base_type langhook.
 233    See also cp/semantics.c (finish_underlying_type).  */
 234
 235 static
 236 tree cxx_enum_underlying_base_type (const_tree type)
 237 {
 238   tree underlying_type = ENUM_UNDERLYING_TYPE (type);
 239
 240   if (! ENUM_FIXED_UNDERLYING_TYPE_P (type))
 241     underlying_type
 242       = c_common_type_for_mode (TYPE_MODE (underlying_type),
 243                                 TYPE_UNSIGNED (underlying_type));
 244
 245   return underlying_type;
 246 }
 247
 248 #include "gt-cp-cp-lang.h"
 249 #include "gtype-cp.h"