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