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