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