gcc/c-objc-common.c

   1 /* Some code common to C and ObjC front ends.
   2    Copyright (C) 2001, 2002, 2003 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 DECL_DECLARED_INLINE_P (fn) && DECL_EXTERNAL (fn);
  65 }
  66
  67 int
  68 c_cannot_inline_tree_fn (tree *fnp)
  69 {
  70   tree fn = *fnp;
  71   tree t;
  72   bool do_warning = (warn_inline
  73                      && DECL_INLINE (fn)
  74                      && DECL_DECLARED_INLINE_P (fn)
  75                      && !DECL_IN_SYSTEM_HEADER (fn));
  76
  77   if (flag_really_no_inline
  78       && lookup_attribute ("always_inline", DECL_ATTRIBUTES (fn)) == NULL)
  79     {
  80       if (do_warning)
  81         warning ("%Jfunction '%F' can never be inlined because it "
  82                  "is supressed using -fno-inline", fn, fn);
  83       goto cannot_inline;
  84     }
  85
  86   /* Don't auto-inline anything that might not be bound within
  87      this unit of translation.  */
  88   if (!DECL_DECLARED_INLINE_P (fn) && !(*targetm.binds_local_p) (fn))
  89     {
  90       if (do_warning)
  91         warning ("%Jfunction '%F' can never be inlined because it might not "
  92                  "be bound within this unit of translation", fn, fn);
  93       goto cannot_inline;
  94     }
  95
  96   if (! function_attribute_inlinable_p (fn))
  97     {
  98       if (do_warning)
  99         warning ("%Jfunction '%F' can never be inlined because it uses "
 100                  "attributes conflicting with inlining", fn, fn);
 101       goto cannot_inline;
 102     }
 103
 104   /* If a function has pending sizes, we must not defer its
 105      compilation, and we can't inline it as a tree.  */
 106   if (fn == current_function_decl)
 107     {
 108       t = get_pending_sizes ();
 109       put_pending_sizes (t);
 110
 111       if (t)
 112         {
 113           if (do_warning)
 114             warning ("%Jfunction '%F' can never be inlined because it has "
 115                      "pending sizes", fn, fn);
 116           goto cannot_inline;
 117         }
 118     }
 119
 120   if (! DECL_FILE_SCOPE_P (fn))
 121     {
 122       /* If a nested function has pending sizes, we may have already
 123          saved them.  */
 124       if (DECL_LANG_SPECIFIC (fn)->pending_sizes)
 125         {
 126           if (do_warning)
 127             warning ("%Jnested function '%F' can never be inlined because it "
 128                      "has possibly saved pending sizes", fn, fn);
 129           goto cannot_inline;
 130         }
 131     }
 132
 133   return 0;
 134
 135  cannot_inline:
 136   DECL_UNINLINABLE (fn) = 1;
 137   return 1;
 138 }
 139
 140 /* Called from check_global_declarations.  */
 141
 142 bool
 143 c_warn_unused_global_decl (tree decl)
 144 {
 145   if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl))
 146     return false;
 147   if (DECL_IN_SYSTEM_HEADER (decl))
 148     return false;
 149
 150   return true;
 151 }
 152
 153 /* Initialization common to C and Objective-C front ends.  */
 154 bool
 155 c_objc_common_init (void)
 156 {
 157   static const enum tree_code stmt_codes[] = {
 158     c_common_stmt_codes
 159   };
 160
 161   INIT_STATEMENT_CODES (stmt_codes);
 162
 163   c_init_decl_processing ();
 164
 165   if (c_common_init () == false)
 166     return false;
 167
 168   lang_expand_decl_stmt = c_expand_decl_stmt;
 169
 170   /* These were not defined in the Objective-C front end, but I'm
 171      putting them here anyway.  The diagnostic format decoder might
 172      want an enhanced ObjC implementation.  */
 173   diagnostic_format_decoder (global_dc) = &c_tree_printer;
 174   lang_missing_noreturn_ok_p = &c_missing_noreturn_ok_p;
 175
 176   /* If still unspecified, make it match -std=c99
 177      (allowing for -pedantic-errors).  */
 178   if (mesg_implicit_function_declaration < 0)
 179     {
 180       if (flag_isoc99)
 181         mesg_implicit_function_declaration = flag_pedantic_errors ? 2 : 1;
 182       else
 183         mesg_implicit_function_declaration = 0;
 184     }
 185
 186   return true;
 187 }
 188
 189 static tree
 190 start_cdtor (int method_type)
 191 {
 192   tree fnname = get_file_function_name (method_type);
 193   tree void_list_node_1 = build_tree_list (NULL_TREE, void_type_node);
 194   tree body;
 195
 196   start_function (void_list_node_1,
 197                   build_nt (CALL_EXPR, fnname,
 198                             tree_cons (NULL_TREE, NULL_TREE, void_list_node_1),
 199                             NULL_TREE),
 200                   NULL_TREE);
 201   store_parm_decls ();
 202
 203   current_function_cannot_inline
 204     = "static constructors and destructors cannot be inlined";
 205
 206   body = c_begin_compound_stmt ();
 207
 208   pushlevel (0);
 209   clear_last_expr ();
 210   add_scope_stmt (/*begin_p=*/1, /*partial_p=*/0);
 211
 212   return body;
 213 }
 214
 215 static void
 216 finish_cdtor (tree body)
 217 {
 218   tree scope;
 219   tree block;
 220
 221   scope = add_scope_stmt (/*begin_p=*/0, /*partial_p=*/0);
 222   block = poplevel (0, 0, 0);
 223   SCOPE_STMT_BLOCK (TREE_PURPOSE (scope)) = block;
 224   SCOPE_STMT_BLOCK (TREE_VALUE (scope)) = block;
 225
 226   RECHAIN_STMTS (body, COMPOUND_BODY (body));
 227
 228   finish_function ();
 229 }
 230
 231 /* Called at end of parsing, but before end-of-file processing.  */
 232
 233 void
 234 c_objc_common_finish_file (void)
 235 {
 236   if (pch_file)
 237     c_common_write_pch ();
 238
 239   /* If multiple translation units were built, copy information between
 240      them based on linkage rules.  */
 241   merge_translation_unit_decls ();
 242
 243   cgraph_finalize_compilation_unit ();
 244   cgraph_optimize ();
 245
 246   if (static_ctors)
 247     {
 248       tree body = start_cdtor ('I');
 249
 250       for (; static_ctors; static_ctors = TREE_CHAIN (static_ctors))
 251         c_expand_expr_stmt (build_function_call (TREE_VALUE (static_ctors),
 252                                                  NULL_TREE));
 253
 254       finish_cdtor (body);
 255     }
 256
 257   if (static_dtors)
 258     {
 259       tree body = start_cdtor ('D');
 260
 261       for (; static_dtors; static_dtors = TREE_CHAIN (static_dtors))
 262         c_expand_expr_stmt (build_function_call (TREE_VALUE (static_dtors),
 263                                                  NULL_TREE));
 264
 265       finish_cdtor (body);
 266     }
 267
 268   {
 269     int flags;
 270     FILE *stream = dump_begin (TDI_all, &flags);
 271
 272     if (stream)
 273       {
 274         dump_node (getdecls (), flags & ~TDF_SLIM, stream);
 275         dump_end (TDI_all, stream);
 276       }
 277   }
 278 }
 279
 280 /* Called during diagnostic message formatting process to print a
 281    source-level entity onto BUFFER.  The meaning of the format specifiers
 282    is as follows:
 283    %D: a general decl,
 284    %E: An expression,
 285    %F: a function declaration,
 286    %T: a type.
 287
 288    These format specifiers form a subset of the format specifiers set used
 289    by the C++ front-end.
 290    Please notice when called, the `%' part was already skipped by the
 291    diagnostic machinery.  */
 292 static bool
 293 c_tree_printer (pretty_printer *pp, text_info *text)
 294 {
 295   tree t = va_arg (*text->args_ptr, tree);
 296
 297   switch (*text->format_spec)
 298     {
 299     case 'D':
 300     case 'F':
 301     case 'T':
 302       {
 303         const char *n = DECL_NAME (t)
 304           ? (*lang_hooks.decl_printable_name) (t, 2)
 305           : "({anonymous})";
 306         pp_string (pp, n);
 307       }
 308       return true;
 309
 310     case 'E':
 311        if (TREE_CODE (t) == IDENTIFIER_NODE)
 312          {
 313            pp_string (pp, IDENTIFIER_POINTER (t));
 314            return true;
 315          }
 316        return false;
 317
 318     default:
 319       return false;
 320     }
 321 }