gcc/cp/cp-objcp-common.c

   1 /* Some code common to C++ and ObjC++ front ends.
   2    Copyright (C) 2004-2016 Free Software Foundation, Inc.
   3    Contributed by Ziemowit Laski  <zlaski@apple.com>
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 3, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 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 "cp-tree.h"
  25 #include "cp-objcp-common.h"
  26
  27 /* Special routine to get the alias set for C++.  */
  28
  29 alias_set_type
  30 cxx_get_alias_set (tree t)
  31 {
  32   if (IS_FAKE_BASE_TYPE (t))
  33     /* The base variant of a type must be in the same alias set as the
  34        complete type.  */
  35     return get_alias_set (TYPE_CONTEXT (t));
  36
  37   /* Punt on PMFs until we canonicalize functions properly.  */
  38   if (TYPE_PTRMEMFUNC_P (t)
  39       || (POINTER_TYPE_P (t)
  40           && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))))
  41     return 0;
  42
  43   return c_common_get_alias_set (t);
  44 }
  45
  46 /* Called from check_global_declaration.  */
  47
  48 bool
  49 cxx_warn_unused_global_decl (const_tree decl)
  50 {
  51   if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl))
  52     return false;
  53   if (DECL_IN_SYSTEM_HEADER (decl))
  54     return false;
  55
  56   return true;
  57 }
  58
  59 /* Langhook for tree_size: determine size of our 'x' and 'c' nodes.  */
  60 size_t
  61 cp_tree_size (enum tree_code code)
  62 {
  63   switch (code)
  64     {
  65     case PTRMEM_CST:            return sizeof (struct ptrmem_cst);
  66     case BASELINK:              return sizeof (struct tree_baselink);
  67     case TEMPLATE_PARM_INDEX:   return sizeof (template_parm_index);
  68     case DEFAULT_ARG:           return sizeof (struct tree_default_arg);
  69     case DEFERRED_NOEXCEPT:     return sizeof (struct tree_deferred_noexcept);
  70     case OVERLOAD:              return sizeof (struct tree_overload);
  71     case STATIC_ASSERT:         return sizeof (struct tree_static_assert);
  72     case TYPE_ARGUMENT_PACK:
  73     case TYPE_PACK_EXPANSION:
  74       return sizeof (struct tree_common);
  75
  76     case NONTYPE_ARGUMENT_PACK:
  77     case EXPR_PACK_EXPANSION:
  78       return sizeof (struct tree_exp);
  79
  80     case ARGUMENT_PACK_SELECT:
  81       return sizeof (struct tree_argument_pack_select);
  82
  83     case TRAIT_EXPR:
  84       return sizeof (struct tree_trait_expr);
  85
  86     case LAMBDA_EXPR:           return sizeof (struct tree_lambda_expr);
  87
  88     case TEMPLATE_INFO:         return sizeof (struct tree_template_info);
  89
  90     case CONSTRAINT_INFO:       return sizeof (struct tree_constraint_info);
  91
  92     case USERDEF_LITERAL:       return sizeof (struct tree_userdef_literal);
  93
  94     case TEMPLATE_DECL:         return sizeof (struct tree_template_decl);
  95
  96     default:
  97       if (TREE_CODE_CLASS (code) == tcc_declaration)
  98         return sizeof (struct tree_decl_non_common);
  99       gcc_unreachable ();
 100     }
 101   /* NOTREACHED */
 102 }
 103
 104 /* Returns true if T is a variably modified type, in the sense of C99.
 105    FN is as passed to variably_modified_p.
 106    This routine needs only check cases that cannot be handled by the
 107    language-independent logic in tree.c.  */
 108
 109 bool
 110 cp_var_mod_type_p (tree type, tree fn)
 111 {
 112   /* If TYPE is a pointer-to-member, it is variably modified if either
 113      the class or the member are variably modified.  */
 114   if (TYPE_PTRMEM_P (type))
 115     return (variably_modified_type_p (TYPE_PTRMEM_CLASS_TYPE (type), fn)
 116             || variably_modified_type_p (TYPE_PTRMEM_POINTED_TO_TYPE (type),
 117                                          fn));
 118
 119   /* All other types are not variably modified.  */
 120   return false;
 121 }
 122
 123 /* This compares two types for equivalence ("compatible" in C-based languages).
 124    This routine should only return 1 if it is sure.  It should not be used
 125    in contexts where erroneously returning 0 causes problems.  */
 126
 127 int
 128 cxx_types_compatible_p (tree x, tree y)
 129 {
 130   return same_type_ignoring_top_level_qualifiers_p (x, y);
 131 }
 132
 133 /* Return true if DECL is explicit member function.  */
 134
 135 bool
 136 cp_function_decl_explicit_p (const_tree decl)
 137 {
 138   return (decl
 139           && DECL_LANG_SPECIFIC (STRIP_TEMPLATE (decl))
 140           && DECL_NONCONVERTING_P (decl));
 141 }
 142
 143 /* Return true if DECL is deleted special member function.  */
 144
 145 bool
 146 cp_function_decl_deleted_p (const_tree decl)
 147 {
 148   return (decl
 149           && DECL_LANG_SPECIFIC (STRIP_TEMPLATE (decl))
 150           && DECL_DELETED_FN (decl));
 151 }
 152
 153 /* Returns 0 if DECL is NOT a C++11 defaulted special member function,
 154    1 if it is explicitly defaulted within the class body, or 2 if it
 155    is explicitly defaulted outside the class body.  */
 156
 157 int
 158 cp_function_decl_defaulted (const_tree decl)
 159 {
 160   if (decl
 161       && DECL_LANG_SPECIFIC (STRIP_TEMPLATE (decl))
 162       && DECL_DEFAULTED_FN (decl))
 163     {
 164       if (DECL_DEFAULTED_IN_CLASS_P (decl))
 165         return 1;
 166
 167       if (DECL_DEFAULTED_OUTSIDE_CLASS_P (decl))
 168         return 2;
 169     }
 170
 171   return 0;
 172 }
 173
 174 /* Stubs to keep c-opts.c happy.  */
 175 void
 176 push_file_scope (void)
 177 {
 178 }
 179
 180 void
 181 pop_file_scope (void)
 182 {
 183 }
 184
 185 /* c-pragma.c needs to query whether a decl has extern "C" linkage.  */
 186 bool
 187 has_c_linkage (const_tree decl)
 188 {
 189   return DECL_EXTERN_C_P (decl);
 190 }
 191
 192 static GTY ((cache))
 193      hash_table<tree_decl_map_cache_hasher> *shadowed_var_for_decl;
 194
 195 /* Lookup a shadowed var for FROM, and return it if we find one.  */
 196
 197 tree
 198 decl_shadowed_for_var_lookup (tree from)
 199 {
 200   struct tree_decl_map *h, in;
 201   in.base.from = from;
 202
 203   h = shadowed_var_for_decl->find_with_hash (&in, DECL_UID (from));
 204   if (h)
 205     return h->to;
 206   return NULL_TREE;
 207 }
 208
 209 /* Insert a mapping FROM->TO in the shadowed var hashtable.  */
 210
 211 void
 212 decl_shadowed_for_var_insert (tree from, tree to)
 213 {
 214   struct tree_decl_map *h;
 215
 216   h = ggc_alloc<tree_decl_map> ();
 217   h->base.from = from;
 218   h->to = to;
 219   *shadowed_var_for_decl->find_slot_with_hash (h, DECL_UID (from), INSERT) = h;
 220 }
 221
 222 void
 223 init_shadowed_var_for_decl (void)
 224 {
 225   shadowed_var_for_decl
 226     = hash_table<tree_decl_map_cache_hasher>::create_ggc (512);
 227 }
 228
 229 /* Return true if stmt can fall through.  Used by block_may_fallthru
 230    default case.  */
 231
 232 bool
 233 cxx_block_may_fallthru (const_tree stmt)
 234 {
 235   switch (TREE_CODE (stmt))
 236     {
 237     case EXPR_STMT:
 238       return block_may_fallthru (EXPR_STMT_EXPR (stmt));
 239
 240     case THROW_EXPR:
 241       return false;
 242
 243     default:
 244       return true;
 245     }
 246 }
 247
 248 void
 249 cp_common_init_ts (void)
 250 {
 251   MARK_TS_DECL_NON_COMMON (USING_DECL);
 252   MARK_TS_DECL_COMMON (TEMPLATE_DECL);
 253   MARK_TS_DECL_COMMON (WILDCARD_DECL);
 254
 255   MARK_TS_COMMON (TEMPLATE_TEMPLATE_PARM);
 256   MARK_TS_COMMON (TEMPLATE_TYPE_PARM);
 257   MARK_TS_COMMON (TEMPLATE_PARM_INDEX);
 258   MARK_TS_COMMON (OVERLOAD);
 259   MARK_TS_COMMON (TEMPLATE_INFO);
 260   MARK_TS_COMMON (TYPENAME_TYPE);
 261   MARK_TS_COMMON (TYPEOF_TYPE);
 262   MARK_TS_COMMON (UNDERLYING_TYPE);
 263   MARK_TS_COMMON (BASELINK);
 264   MARK_TS_COMMON (TYPE_PACK_EXPANSION);
 265   MARK_TS_COMMON (TYPE_ARGUMENT_PACK);
 266   MARK_TS_COMMON (DECLTYPE_TYPE);
 267   MARK_TS_COMMON (BOUND_TEMPLATE_TEMPLATE_PARM);
 268   MARK_TS_COMMON (UNBOUND_CLASS_TEMPLATE);
 269
 270   MARK_TS_TYPED (EXPR_PACK_EXPANSION);
 271   MARK_TS_TYPED (SWITCH_STMT);
 272   MARK_TS_TYPED (IF_STMT);
 273   MARK_TS_TYPED (FOR_STMT);
 274   MARK_TS_TYPED (RANGE_FOR_STMT);
 275   MARK_TS_TYPED (AGGR_INIT_EXPR);
 276   MARK_TS_TYPED (EXPR_STMT);
 277   MARK_TS_TYPED (EH_SPEC_BLOCK);
 278   MARK_TS_TYPED (CLEANUP_STMT);
 279   MARK_TS_TYPED (SCOPE_REF);
 280   MARK_TS_TYPED (CAST_EXPR);
 281   MARK_TS_TYPED (NON_DEPENDENT_EXPR);
 282   MARK_TS_TYPED (MODOP_EXPR);
 283   MARK_TS_TYPED (TRY_BLOCK);
 284   MARK_TS_TYPED (THROW_EXPR);
 285   MARK_TS_TYPED (HANDLER);
 286   MARK_TS_TYPED (REINTERPRET_CAST_EXPR);
 287   MARK_TS_TYPED (CONST_CAST_EXPR);
 288   MARK_TS_TYPED (STATIC_CAST_EXPR);
 289   MARK_TS_TYPED (DYNAMIC_CAST_EXPR);
 290   MARK_TS_TYPED (IMPLICIT_CONV_EXPR);
 291   MARK_TS_TYPED (TEMPLATE_ID_EXPR);
 292   MARK_TS_TYPED (ARROW_EXPR);
 293   MARK_TS_TYPED (SIZEOF_EXPR);
 294   MARK_TS_TYPED (ALIGNOF_EXPR);
 295   MARK_TS_TYPED (AT_ENCODE_EXPR);
 296   MARK_TS_TYPED (UNARY_PLUS_EXPR);
 297   MARK_TS_TYPED (TRAIT_EXPR);
 298   MARK_TS_TYPED (TYPE_ARGUMENT_PACK);
 299   MARK_TS_TYPED (NOEXCEPT_EXPR);
 300   MARK_TS_TYPED (NONTYPE_ARGUMENT_PACK);
 301   MARK_TS_TYPED (WHILE_STMT);
 302   MARK_TS_TYPED (NEW_EXPR);
 303   MARK_TS_TYPED (VEC_NEW_EXPR);
 304   MARK_TS_TYPED (BREAK_STMT);
 305   MARK_TS_TYPED (MEMBER_REF);
 306   MARK_TS_TYPED (DOTSTAR_EXPR);
 307   MARK_TS_TYPED (DO_STMT);
 308   MARK_TS_TYPED (DELETE_EXPR);
 309   MARK_TS_TYPED (VEC_DELETE_EXPR);
 310   MARK_TS_TYPED (CONTINUE_STMT);
 311   MARK_TS_TYPED (TAG_DEFN);
 312   MARK_TS_TYPED (PSEUDO_DTOR_EXPR);
 313   MARK_TS_TYPED (TYPEID_EXPR);
 314   MARK_TS_TYPED (MUST_NOT_THROW_EXPR);
 315   MARK_TS_TYPED (STMT_EXPR);
 316   MARK_TS_TYPED (OFFSET_REF);
 317   MARK_TS_TYPED (OFFSETOF_EXPR);
 318   MARK_TS_TYPED (ADDRESSOF_EXPR);
 319   MARK_TS_TYPED (PTRMEM_CST);
 320   MARK_TS_TYPED (EMPTY_CLASS_EXPR);
 321   MARK_TS_TYPED (VEC_INIT_EXPR);
 322   MARK_TS_TYPED (USING_STMT);
 323   MARK_TS_TYPED (LAMBDA_EXPR);
 324   MARK_TS_TYPED (CTOR_INITIALIZER);
 325   MARK_TS_TYPED (ARRAY_NOTATION_REF);
 326   MARK_TS_TYPED (REQUIRES_EXPR);
 327   MARK_TS_TYPED (UNARY_LEFT_FOLD_EXPR);
 328   MARK_TS_TYPED (UNARY_RIGHT_FOLD_EXPR);
 329   MARK_TS_TYPED (BINARY_LEFT_FOLD_EXPR);
 330   MARK_TS_TYPED (BINARY_RIGHT_FOLD_EXPR);
 331 }
 332
 333 #include "gt-cp-cp-objcp-common.h"