1/* LTO symbol table merging. 2 Copyright (C) 2009-2020 Free Software Foundation, Inc. 3 4This file is part of GCC. 5 6GCC is free software; you can redistribute it and/or modify it under 7the terms of the GNU General Public License as published by the Free 8Software Foundation; either version 3, or (at your option) any later 9version. 10 11GCC is distributed in the hope that it will be useful, but WITHOUT ANY 12WARRANTY; without even the implied warranty of MERCHANTABILITY or 13FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14for more details. 15 16You should have received a copy of the GNU General Public License 17along with GCC; see the file COPYING3. If not see 18<http://www.gnu.org/licenses/>. */ 19 20extern void lto_symtab_merge_decls (void); 21extern void lto_symtab_merge_symbols (void); 22extern tree lto_symtab_prevailing_decl (tree decl); 23extern 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 31inline void 32lto_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 42inline tree 43lto_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