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_UNSAFE_FOR_REEVAL
  69 #define LANG_HOOKS_UNSAFE_FOR_REEVAL c_common_unsafe_for_reeval
  70 #undef LANG_HOOKS_PRINT_STATISTICS
  71 #define LANG_HOOKS_PRINT_STATISTICS cxx_print_statistics
  72 #undef LANG_HOOKS_PRINT_XNODE
  73 #define LANG_HOOKS_PRINT_XNODE cxx_print_xnode
  74 #undef LANG_HOOKS_PRINT_DECL
  75 #define LANG_HOOKS_PRINT_DECL cxx_print_decl
  76 #undef LANG_HOOKS_PRINT_TYPE
  77 #define LANG_HOOKS_PRINT_TYPE cxx_print_type
  78 #undef LANG_HOOKS_PRINT_IDENTIFIER
  79 #define LANG_HOOKS_PRINT_IDENTIFIER cxx_print_identifier
  80 #undef LANG_HOOKS_DECL_PRINTABLE_NAME
  81 #define LANG_HOOKS_DECL_PRINTABLE_NAME  cxx_printable_name
  82 #undef LANG_HOOKS_PRINT_ERROR_FUNCTION
  83 #define LANG_HOOKS_PRINT_ERROR_FUNCTION cxx_print_error_function
  84 #undef LANG_HOOKS_SET_YYDEBUG
  85 #define LANG_HOOKS_SET_YYDEBUG cxx_set_yydebug
  86
  87 #undef LANG_HOOKS_TREE_INLINING_WALK_SUBTREES
  88 #define LANG_HOOKS_TREE_INLINING_WALK_SUBTREES \
  89   cp_walk_subtrees
  90 #undef LANG_HOOKS_TREE_INLINING_CANNOT_INLINE_TREE_FN
  91 #define LANG_HOOKS_TREE_INLINING_CANNOT_INLINE_TREE_FN \
  92   cp_cannot_inline_tree_fn
  93 #undef LANG_HOOKS_TREE_INLINING_ADD_PENDING_FN_DECLS
  94 #define LANG_HOOKS_TREE_INLINING_ADD_PENDING_FN_DECLS \
  95   cp_add_pending_fn_decls
  96 #undef LANG_HOOKS_TREE_INLINING_TREE_CHAIN_MATTERS_P
  97 #define LANG_HOOKS_TREE_INLINING_TREE_CHAIN_MATTERS_P \
  98   cp_is_overload_p
  99 #undef LANG_HOOKS_TREE_INLINING_AUTO_VAR_IN_FN_P
 100 #define LANG_HOOKS_TREE_INLINING_AUTO_VAR_IN_FN_P \
 101   cp_auto_var_in_fn_p
 102 #undef LANG_HOOKS_TREE_INLINING_COPY_RES_DECL_FOR_INLINING
 103 #define LANG_HOOKS_TREE_INLINING_COPY_RES_DECL_FOR_INLINING \
 104   cp_copy_res_decl_for_inlining
 105 #undef LANG_HOOKS_TREE_INLINING_ANON_AGGR_TYPE_P
 106 #define LANG_HOOKS_TREE_INLINING_ANON_AGGR_TYPE_P anon_aggr_type_p
 107 #undef LANG_HOOKS_TREE_INLINING_START_INLINING
 108 #define LANG_HOOKS_TREE_INLINING_START_INLINING cp_start_inlining
 109 #undef LANG_HOOKS_TREE_INLINING_END_INLINING
 110 #define LANG_HOOKS_TREE_INLINING_END_INLINING cp_end_inlining
 111 #undef LANG_HOOKS_TREE_DUMP_DUMP_TREE_FN
 112 #define LANG_HOOKS_TREE_DUMP_DUMP_TREE_FN cp_dump_tree
 113 #undef LANG_HOOKS_TREE_DUMP_TYPE_QUALS_FN
 114 #define LANG_HOOKS_TREE_DUMP_TYPE_QUALS_FN cp_type_quals
 115
 116 #undef LANG_HOOKS_MAKE_TYPE
 117 #define LANG_HOOKS_MAKE_TYPE cxx_make_type
 118 #undef LANG_HOOKS_TYPE_FOR_MODE
 119 #define LANG_HOOKS_TYPE_FOR_MODE c_common_type_for_mode
 120 #undef LANG_HOOKS_TYPE_FOR_SIZE
 121 #define LANG_HOOKS_TYPE_FOR_SIZE c_common_type_for_size
 122
 123 /* Each front end provides its own hooks, for toplev.c.  */
 124 const struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;
 125
 126 /* Check if a C++ type is safe for aliasing.
 127    Return TRUE if T safe for aliasing FALSE otherwise.  */
 128
 129 static bool
 130 ok_to_generate_alias_set_for_type (t)
 131      tree t;
 132 {
 133   if (TYPE_PTRMEMFUNC_P (t))
 134     return true;
 135   if (AGGREGATE_TYPE_P (t))
 136     {
 137       if ((TREE_CODE (t) == RECORD_TYPE) || (TREE_CODE (t) == UNION_TYPE))
 138         {
 139           tree fields;
 140           /* PODs are safe.  */
 141           if (! CLASSTYPE_NON_POD_P(t))
 142             return true;
 143           /* Classes with virtual baseclasses are not.  */
 144           if (TYPE_USES_VIRTUAL_BASECLASSES (t))
 145             return false;
 146           /* Recursively check the base classes.  */
 147           if (TYPE_BINFO (t) != NULL && TYPE_BINFO_BASETYPES (t) != NULL)
 148             {
 149               int i;
 150               for (i = 0; i < TREE_VEC_LENGTH (TYPE_BINFO_BASETYPES (t)); i++)
 151                 {
 152                   tree binfo = TREE_VEC_ELT (TYPE_BINFO_BASETYPES (t), i);
 153                   if (!ok_to_generate_alias_set_for_type (BINFO_TYPE (binfo)))
 154                     return false;
 155                 }
 156             }
 157           /* Check all the fields.  */
 158           for (fields = TYPE_FIELDS (t); fields; fields = TREE_CHAIN (fields))
 159             {
 160               if (TREE_CODE (fields) != FIELD_DECL)
 161                 continue;
 162               if (! ok_to_generate_alias_set_for_type (TREE_TYPE (fields)))
 163                 return false;
 164             }
 165           return true;
 166         }
 167       else if (TREE_CODE (t) == ARRAY_TYPE)
 168         return ok_to_generate_alias_set_for_type (TREE_TYPE (t));
 169       else
 170         /* This should never happen, we dealt with all the aggregate
 171            types that can appear in C++ above.  */
 172         abort ();
 173     }
 174   else
 175     return true;
 176 }
 177
 178 /* Tree code classes. */
 179
 180 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
 181
 182 const char tree_code_type[] = {
 183 #include "tree.def"
 184   'x',
 185 #include "c-common.def"
 186   'x',
 187 #include "cp-tree.def"
 188 };
 189 #undef DEFTREECODE
 190
 191 /* Table indexed by tree code giving number of expression
 192    operands beyond the fixed part of the node structure.
 193    Not used for types or decls.  */
 194
 195 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
 196
 197 const unsigned char tree_code_length[] = {
 198 #include "tree.def"
 199   0,
 200 #include "c-common.def"
 201   0,
 202 #include "cp-tree.def"
 203 };
 204 #undef DEFTREECODE
 205
 206 /* Names of tree components.
 207    Used for printing out the tree and error messages.  */
 208 #define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,
 209
 210 const char *const tree_code_name[] = {
 211 #include "tree.def"
 212   "@@dummy",
 213 #include "c-common.def"
 214   "@@dummy",
 215 #include "cp-tree.def"
 216 };
 217 #undef DEFTREECODE
 218
 219 /* Special routine to get the alias set for C++.  */
 220
 221 static HOST_WIDE_INT
 222 cxx_get_alias_set (t)
 223      tree t;
 224 {
 225   /* It's not yet safe to use alias sets for classes in C++.  */
 226   if (!ok_to_generate_alias_set_for_type(t))
 227     return 0;
 228
 229   return c_common_get_alias_set (t);
 230 }