gcc/cp/cp-lang.c

   1 /* Language-dependent hooks for C++.
   2    Copyright 2001 Free Software Foundation, Inc.
   3    Contributed by Alexandre Oliva  <aoliva@redhat.com>
   4
   5 This file is part of GNU CC.
   6
   7 GNU CC 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 2, or (at your option)
  10 any later version.
  11
  12 GNU CC 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 GNU CC; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "tree.h"
  25 #include "cp-tree.h"
  26 #include "c-common.h"
  27 #include "toplev.h"
  28 #include "langhooks.h"
  29 #include "langhooks-def.h"
  30
  31 static HOST_WIDE_INT cxx_get_alias_set PARAMS ((tree));
  32 static bool ok_to_generate_alias_set_for_type PARAMS ((tree));
  33
  34 #undef LANG_HOOKS_NAME
  35 #define LANG_HOOKS_NAME "GNU C++"
  36 #undef LANG_HOOKS_INIT
  37 #define LANG_HOOKS_INIT cxx_init
  38 #undef LANG_HOOKS_FINISH
  39 #define LANG_HOOKS_FINISH cxx_finish
  40 #undef LANG_HOOKS_CLEAR_BINDING_STACK
  41 #define LANG_HOOKS_CLEAR_BINDING_STACK pop_everything
  42 #undef LANG_HOOKS_INIT_OPTIONS
  43 #define LANG_HOOKS_INIT_OPTIONS cxx_init_options
  44 #undef LANG_HOOKS_DECODE_OPTION
  45 #define LANG_HOOKS_DECODE_OPTION cxx_decode_option
  46 #undef LANG_HOOKS_POST_OPTIONS
  47 #define LANG_HOOKS_POST_OPTIONS cxx_post_options
  48 #undef LANG_HOOKS_GET_ALIAS_SET
  49 #define LANG_HOOKS_GET_ALIAS_SET cxx_get_alias_set
  50 #undef LANG_HOOKS_EXPAND_CONSTANT
  51 #define LANG_HOOKS_EXPAND_CONSTANT cplus_expand_constant
  52 #undef LANG_HOOKS_EXPAND_EXPR
  53 #define LANG_HOOKS_EXPAND_EXPR cxx_expand_expr
  54 #undef LANG_HOOKS_SAFE_FROM_P
  55 #define LANG_HOOKS_SAFE_FROM_P c_safe_from_p
  56 #undef LANG_HOOKS_PARSE_FILE
  57 #define LANG_HOOKS_PARSE_FILE c_common_parse_file
  58 #undef LANG_HOOKS_DUP_LANG_SPECIFIC_DECL
  59 #define LANG_HOOKS_DUP_LANG_SPECIFIC_DECL cxx_dup_lang_specific_decl
  60 #undef LANG_HOOKS_UNSAVE_EXPR_NOW
  61 #define LANG_HOOKS_UNSAVE_EXPR_NOW cxx_unsave_expr_now
  62 #undef LANG_HOOKS_MAYBE_BUILD_CLEANUP
  63 #define LANG_HOOKS_MAYBE_BUILD_CLEANUP cxx_maybe_build_cleanup
  64 #undef LANG_HOOKS_INSERT_DEFAULT_ATTRIBUTES
  65 #define LANG_HOOKS_INSERT_DEFAULT_ATTRIBUTES cxx_insert_default_attributes
  66 #undef LANG_HOOKS_MARK_TREE
  67 #define LANG_HOOKS_MARK_TREE cxx_mark_tree
  68 #undef LANG_HOOKS_PRINT_STATISTICS
  69 #define LANG_HOOKS_PRINT_STATISTICS cxx_print_statistics
  70 #undef LANG_HOOKS_PRINT_XNODE
  71 #define LANG_HOOKS_PRINT_XNODE cxx_print_xnode
  72 #undef LANG_HOOKS_PRINT_DECL
  73 #define LANG_HOOKS_PRINT_DECL cxx_print_decl
  74 #undef LANG_HOOKS_PRINT_TYPE
  75 #define LANG_HOOKS_PRINT_TYPE cxx_print_type
  76 #undef LANG_HOOKS_PRINT_IDENTIFIER
  77 #define LANG_HOOKS_PRINT_IDENTIFIER cxx_print_identifier
  78 #undef LANG_HOOKS_DECL_PRINTABLE_NAME
  79 #define LANG_HOOKS_DECL_PRINTABLE_NAME  cxx_printable_name
  80 #undef LANG_HOOKS_SET_YYDEBUG
  81 #define LANG_HOOKS_SET_YYDEBUG cxx_set_yydebug
  82
  83 #undef LANG_HOOKS_TREE_INLINING_WALK_SUBTREES
  84 #define LANG_HOOKS_TREE_INLINING_WALK_SUBTREES \
  85   cp_walk_subtrees
  86 #undef LANG_HOOKS_TREE_INLINING_CANNOT_INLINE_TREE_FN
  87 #define LANG_HOOKS_TREE_INLINING_CANNOT_INLINE_TREE_FN \
  88   cp_cannot_inline_tree_fn
  89 #undef LANG_HOOKS_TREE_INLINING_ADD_PENDING_FN_DECLS
  90 #define LANG_HOOKS_TREE_INLINING_ADD_PENDING_FN_DECLS \
  91   cp_add_pending_fn_decls
  92 #undef LANG_HOOKS_TREE_INLINING_TREE_CHAIN_MATTERS_P
  93 #define LANG_HOOKS_TREE_INLINING_TREE_CHAIN_MATTERS_P \
  94   cp_is_overload_p
  95 #undef LANG_HOOKS_TREE_INLINING_AUTO_VAR_IN_FN_P
  96 #define LANG_HOOKS_TREE_INLINING_AUTO_VAR_IN_FN_P \
  97   cp_auto_var_in_fn_p
  98 #undef LANG_HOOKS_TREE_INLINING_COPY_RES_DECL_FOR_INLINING
  99 #define LANG_HOOKS_TREE_INLINING_COPY_RES_DECL_FOR_INLINING \
 100   cp_copy_res_decl_for_inlining
 101 #undef LANG_HOOKS_TREE_INLINING_ANON_AGGR_TYPE_P
 102 #define LANG_HOOKS_TREE_INLINING_ANON_AGGR_TYPE_P anon_aggr_type_p
 103 #undef LANG_HOOKS_TREE_INLINING_START_INLINING
 104 #define LANG_HOOKS_TREE_INLINING_START_INLINING cp_start_inlining
 105 #undef LANG_HOOKS_TREE_INLINING_END_INLINING
 106 #define LANG_HOOKS_TREE_INLINING_END_INLINING cp_end_inlining
 107 #undef LANG_HOOKS_TREE_DUMP_DUMP_TREE_FN
 108 #define LANG_HOOKS_TREE_DUMP_DUMP_TREE_FN cp_dump_tree
 109 #undef LANG_HOOKS_TREE_DUMP_TYPE_QUALS_FN
 110 #define LANG_HOOKS_TREE_DUMP_TYPE_QUALS_FN cp_type_quals
 111
 112 /* Each front end provides its own hooks, for toplev.c.  */
 113 const struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;
 114
 115 /* Check if a C++ type is safe for aliasing.
 116    Return TRUE if T safe for aliasing FALSE otherwise.  */
 117
 118 static bool
 119 ok_to_generate_alias_set_for_type (t)
 120      tree t;
 121 {
 122   if (TYPE_PTRMEMFUNC_P (t))
 123     return true;
 124   if (AGGREGATE_TYPE_P (t))
 125     {
 126       if ((TREE_CODE (t) == RECORD_TYPE) || (TREE_CODE (t) == UNION_TYPE))
 127         {
 128           tree fields;
 129           /* PODs are safe.  */
 130           if (! CLASSTYPE_NON_POD_P(t))
 131             return true;
 132           /* Classes with virtual baseclasses are not.  */
 133           if (TYPE_USES_VIRTUAL_BASECLASSES (t))
 134             return false;
 135           /* Recursively check the base classes.  */
 136           if (TYPE_BINFO (t) != NULL && TYPE_BINFO_BASETYPES (t) != NULL)
 137             {
 138               int i;
 139               for (i = 0; i < TREE_VEC_LENGTH (TYPE_BINFO_BASETYPES (t)); i++)
 140                 {
 141                   tree binfo = TREE_VEC_ELT (TYPE_BINFO_BASETYPES (t), i);
 142                   if (!ok_to_generate_alias_set_for_type (BINFO_TYPE (binfo)))
 143                     return false;
 144                 }
 145             }
 146           /* Check all the fields.  */
 147           for (fields = TYPE_FIELDS (t); fields; fields = TREE_CHAIN (fields))
 148             {
 149               if (TREE_CODE (fields) != FIELD_DECL)
 150                 continue;
 151               if (! ok_to_generate_alias_set_for_type (TREE_TYPE (fields)))
 152                 return false;
 153             }
 154           return true;
 155         }
 156       else if (TREE_CODE (t) == ARRAY_TYPE)
 157         return ok_to_generate_alias_set_for_type (TREE_TYPE (t));
 158       else
 159         /* This should never happen, we dealt with all the aggregate
 160            types that can appear in C++ above.  */
 161         abort ();
 162     }
 163   else
 164     return true;
 165 }
 166
 167 /* Tree code classes. */
 168
 169 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
 170
 171 const char tree_code_type[] = {
 172 #include "tree.def"
 173   'x',
 174 #include "c-common.def"
 175   'x',
 176 #include "cp-tree.def"
 177 };
 178 #undef DEFTREECODE
 179
 180 /* Table indexed by tree code giving number of expression
 181    operands beyond the fixed part of the node structure.
 182    Not used for types or decls.  */
 183
 184 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
 185
 186 const unsigned char tree_code_length[] = {
 187 #include "tree.def"
 188   0,
 189 #include "c-common.def"
 190   0,
 191 #include "cp-tree.def"
 192 };
 193 #undef DEFTREECODE
 194
 195 /* Names of tree components.
 196    Used for printing out the tree and error messages.  */
 197 #define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,
 198
 199 const char *const tree_code_name[] = {
 200 #include "tree.def"
 201   "@@dummy",
 202 #include "c-common.def"
 203   "@@dummy",
 204 #include "cp-tree.def"
 205 };
 206 #undef DEFTREECODE
 207
 208 /* Special routine to get the alias set for C++.  */
 209
 210 static HOST_WIDE_INT
 211 cxx_get_alias_set (t)
 212      tree t;
 213 {
 214   /* It's not yet safe to use alias sets for classes in C++.  */
 215   if (!ok_to_generate_alias_set_for_type(t))
 216     return 0;
 217
 218   return c_common_get_alias_set (t);
 219 }