xref: /dragonfly/contrib/gcc-8.0/gcc/lto/lto-symtab.h (revision ed183f8c)
1 /* LTO symbol table merging.
2    Copyright (C) 2009-2018 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 3, 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 COPYING3.  If not see
18 <http://www.gnu.org/licenses/>.  */
19 
20 extern void lto_symtab_merge_decls (void);
21 extern void lto_symtab_merge_symbols (void);
22 extern tree lto_symtab_prevailing_decl (tree decl);
23 extern tree lto_symtab_prevailing_virtual_decl (tree decl);
24 
25 /* Mark DECL to be previailed by PREVAILING.
26    Use DECL_LANG_FLAG_0 and DECL_CHAIN as special markers; those do not
27    disturb debug_tree and diagnostics.
28    We are safe to modify them as we wish, because the declarations disappear
29    from the IL after the merging.  */
30 
31 inline void
32 lto_symtab_prevail_decl (tree prevailing, tree decl)
33 {
34   gcc_checking_assert (! DECL_LANG_FLAG_0 (decl));
35   gcc_assert (TREE_PUBLIC (decl) || DECL_EXTERNAL (decl));
36   DECL_CHAIN (decl) = prevailing;
37   DECL_LANG_FLAG_0 (decl) = 1;
38 }
39 
40 /* Given the decl DECL, return the prevailing decl with the same name. */
41 
42 inline tree
43 lto_symtab_prevailing_decl (tree decl)
44 {
45   if (DECL_LANG_FLAG_0 (decl))
46     return DECL_CHAIN (decl);
47   else
48     {
49       if ((TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == FUNCTION_DECL)
50 	  && DECL_VIRTUAL_P (decl)
51 	  && (TREE_PUBLIC (decl) || DECL_EXTERNAL (decl))
52 	  && !symtab_node::get (decl))
53 	return lto_symtab_prevailing_virtual_decl (decl);
54       return decl;
55     }
56 }
57