gcc/c-objc-common.c

   1 /* Some code common to C and ObjC front ends.
   2    Copyright (C) 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 2, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING.  If not, write to the Free
  18 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  19 02111-1307, USA.  */
  20
  21 #include "config.h"
  22 #include "system.h"
  23 #include "coretypes.h"
  24 #include "tm.h"
  25 #include "tree.h"
  26 #include "rtl.h"
  27 #include "insn-config.h"
  28 #include "integrate.h"
  29 #include "expr.h"
  30 #include "c-tree.h"
  31 #include "function.h"
  32 #include "flags.h"
  33 #include "toplev.h"
  34 #include "diagnostic.h"
  35 #include "tree-inline.h"
  36 #include "varray.h"
  37 #include "ggc.h"
  38 #include "langhooks.h"
  39 #include "target.h"
  40 #include "cgraph.h"
  41
  42 static bool c_tree_printer (pretty_printer *, text_info *);
  43 static tree start_cdtor (int);
  44 static void finish_cdtor (tree);
  45
  46 int
  47 c_missing_noreturn_ok_p (tree decl)
  48 {
  49   /* A missing noreturn is not ok for freestanding implementations and
  50      ok for the `main' function in hosted implementations.  */
  51   return flag_hosted && MAIN_NAME_P (DECL_ASSEMBLER_NAME (decl));
  52 }
  53
  54 /* We want to inline `extern inline' functions even if this would
  55    violate inlining limits.  Some glibc and linux constructs depend on
  56    such functions always being inlined when optimizing.  */
  57
  58 int
  59 c_disregard_inline_limits (tree fn)
  60 {
  61   if (lookup_attribute ("always_inline", DECL_ATTRIBUTES (fn)) != NULL)
  62     return 1;
  63
  64   return (!flag_really_no_inline && DECL_DECLARED_INLINE_P (fn)
  65           && DECL_EXTERNAL (fn));
  66 }
  67
  68 int
  69 c_cannot_inline_tree_fn (tree *fnp)
  70 {
  71   tree fn = *fnp;
  72   tree t;
  73   bool do_warning = (warn_inline
  74                      && DECL_INLINE (fn)
  75                      && DECL_DECLARED_INLINE_P (fn)
  76                      && !DECL_IN_SYSTEM_HEADER (fn));
  77
  78   if (flag_really_no_inline
  79       && lookup_attribute ("always_inline", DECL_ATTRIBUTES (fn)) == NULL)
  80     {
  81       if (do_warning)
  82         warning ("%Jfunction '%F' can never be inlined because it "
  83                  "is suppressed using -fno-inline", fn, fn);
  84       goto cannot_inline;
  85     }
  86
  87   /* Don't auto-inline anything that might not be bound within
  88      this unit of translation.  */
  89   if (!DECL_DECLARED_INLINE_P (fn) && !(*targetm.binds_local_p) (fn))
  90     {
  91       if (do_warning)
  92         warning ("%Jfunction '%F' can never be inlined because it might not "
  93                  "be bound within this unit of translation", fn, fn);
  94       goto cannot_inline;
  95     }
  96
  97   if (! function_attribute_inlinable_p (fn))
  98     {
  99       if (do_warning)
 100         warning ("%Jfunction '%F' can never be inlined because it uses "
 101                  "attributes conflicting with inlining", fn, fn);
 102       goto cannot_inline;
 103     }
 104
 105   /* If a function has pending sizes, we must not defer its
 106      compilation, and we can't inline it as a tree.  */
 107   if (fn == current_function_decl)
 108     {
 109       t = get_pending_sizes ();
 110       put_pending_sizes (t);
 111
 112       if (t)
 113         {
 114           if (do_warning)
 115             warning ("%Jfunction '%F' can never be inlined because it has "
 116                      "pending sizes", fn, fn);
 117           goto cannot_inline;
 118         }
 119     }
 120
 121   if (! DECL_FILE_SCOPE_P (fn))
 122     {
 123       /* If a nested function has pending sizes, we may have already
 124          saved them.  */
 125       if (DECL_LANG_SPECIFIC (fn)->pending_sizes)
 126         {
 127           if (do_warning)
 128             warning ("%Jnested function '%F' can never be inlined because it "
 129                      "has possibly saved pending sizes", fn, fn);
 130           goto cannot_inline;
 131         }
 132     }
 133
 134   return 0;
 135
 136  cannot_inline:
 137   DECL_UNINLINABLE (fn) = 1;
 138   return 1;
 139 }
 140
 141 /* Called from check_global_declarations.  */
 142
 143 bool
 144 c_warn_unused_global_decl (tree decl)
 145 {
 146   if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl))
 147     return false;
 148   if (DECL_IN_SYSTEM_HEADER (decl))
 149     return false;
 150
 151   return true;
 152 }
 153
 154 /* Initialization common to C and Objective-C front ends.  */
 155 bool
 156 c_objc_common_init (void)
 157 {
 158   static const enum tree_code stmt_codes[] = {
 159     c_common_stmt_codes
 160   };
 161
 162   INIT_STATEMENT_CODES (stmt_codes);
 163
 164   c_init_decl_processing ();
 165
 166   if (c_common_init () == false)
 167     return false;
 168
 169   lang_expand_decl_stmt = c_expand_decl_stmt;
 170
 171   /* These were not defined in the Objective-C front end, but I'm
 172      putting them here anyway.  The diagnostic format decoder might
 173      want an enhanced ObjC implementation.  */
 174   diagnostic_format_decoder (global_dc) = &c_tree_printer;
 175   lang_missing_noreturn_ok_p = &c_missing_noreturn_ok_p;
 176
 177   /* If still unspecified, make it match -std=c99
 178      (allowing for -pedantic-errors).  */
 179   if (mesg_implicit_function_declaration < 0)
 180     {
 181       if (flag_isoc99)
 182         mesg_implicit_function_declaration = flag_pedantic_errors ? 2 : 1;
 183       else
 184         mesg_implicit_function_declaration = 0;
 185     }
 186
 187   return true;
 188 }
 189
 190 static tree
 191 start_cdtor (int method_type)
 192 {
 193   tree fnname = get_file_function_name (method_type);
 194   tree void_list_node_1 = build_tree_list (NULL_TREE, void_type_node);
 195   tree body;
 196
 197   start_function (void_list_node_1,
 198                   build_nt (CALL_EXPR, fnname,
 199                             tree_cons (NULL_TREE, NULL_TREE, void_list_node_1),
 200                             NULL_TREE),
 201                   NULL_TREE);
 202   store_parm_decls ();
 203
 204   current_function_cannot_inline
 205     = "static constructors and destructors cannot be inlined";
 206
 207   body = c_begin_compound_stmt ();
 208
 209   pushlevel (0);
 210   clear_last_expr ();
 211   add_scope_stmt (/*begin_p=*/1, /*partial_p=*/0);
 212
 213   return body;
 214 }
 215
 216 static void
 217 finish_cdtor (tree body)
 218 {
 219   tree scope;
 220   tree block;
 221
 222   scope = add_scope_stmt (/*begin_p=*/0, /*partial_p=*/0);
 223   block = poplevel (0, 0, 0);
 224   SCOPE_STMT_BLOCK (TREE_PURPOSE (scope)) = block;
 225   SCOPE_STMT_BLOCK (TREE_VALUE (scope)) = block;
 226
 227   RECHAIN_STMTS (body, COMPOUND_BODY (body));
 228
 229   finish_function ();
 230 }
 231
 232 /* Called at end of parsing, but before end-of-file processing.  */
 233
 234 void
 235 c_objc_common_finish_file (void)
 236 {
 237   if (pch_file)
 238     c_common_write_pch ();
 239
 240   /* If multiple translation units were built, copy information between
 241      them based on linkage rules.  */
 242   merge_translation_unit_decls ();
 243
 244   cgraph_finalize_compilation_unit ();
 245   cgraph_optimize ();
 246
 247   if (static_ctors)
 248     {
 249       tree body = start_cdtor ('I');
 250
 251       for (; static_ctors; static_ctors = TREE_CHAIN (static_ctors))
 252         c_expand_expr_stmt (build_function_call (TREE_VALUE (static_ctors),
 253                                                  NULL_TREE));
 254
 255       finish_cdtor (body);
 256     }
 257
 258   if (static_dtors)
 259     {
 260       tree body = start_cdtor ('D');
 261
 262       for (; static_dtors; static_dtors = TREE_CHAIN (static_dtors))
 263         c_expand_expr_stmt (build_function_call (TREE_VALUE (static_dtors),
 264                                                  NULL_TREE));
 265
 266       finish_cdtor (body);
 267     }
 268
 269   {
 270     int flags;
 271     FILE *stream = dump_begin (TDI_all, &flags);
 272
 273     if (stream)
 274       {
 275         dump_node (getdecls (), flags & ~TDF_SLIM, stream);
 276         dump_end (TDI_all, stream);
 277       }
 278   }
 279 }
 280
 281 /* Called during diagnostic message formatting process to print a
 282    source-level entity onto BUFFER.  The meaning of the format specifiers
 283    is as follows:
 284    %D: a general decl,
 285    %E: An expression,
 286    %F: a function declaration,
 287    %T: a type.
 288
 289    These format specifiers form a subset of the format specifiers set used
 290    by the C++ front-end.
 291    Please notice when called, the `%' part was already skipped by the
 292    diagnostic machinery.  */
 293 static bool
 294 c_tree_printer (pretty_printer *pp, text_info *text)
 295 {
 296   tree t = va_arg (*text->args_ptr, tree);
 297   const char *n = "({anonymous})";
 298
 299   switch (*text->format_spec)
 300     {
 301     case 'D':
 302     case 'F':
 303       if (DECL_NAME (t))
 304         n = (*lang_hooks.decl_printable_name) (t, 2);
 305       break;
 306
 307     case 'T':
 308       if (TREE_CODE (t) == TYPE_DECL)
 309         {
 310           if (DECL_NAME (t))
 311             n = (*lang_hooks.decl_printable_name) (t, 2);
 312         }
 313       else
 314         {
 315           t = TYPE_NAME (t);
 316           if (t)
 317             n = IDENTIFIER_POINTER (t);
 318         }
 319       break;
 320
 321     case 'E':
 322       if (TREE_CODE (t) == IDENTIFIER_NODE)
 323         n = IDENTIFIER_POINTER (t);
 324       else
 325         return false;
 326       break;
 327
 328     default:
 329       return false;
 330     }
 331
 332   pp_string (pp, n);
 333   return true;
 334 }