1 /* struct_symbol.h - Internal symbol structure 2 Copyright (C) 1987-2016 Free Software Foundation, Inc. 3 4 This file is part of GAS, the GNU Assembler. 5 6 GAS is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 3, or (at your option) 9 any later version. 10 11 GAS is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GAS; see the file COPYING. If not, write to the Free 18 Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA 19 02110-1301, USA. */ 20 21 #ifndef __struc_symbol_h__ 22 #define __struc_symbol_h__ 23 24 struct symbol_flags 25 { 26 /* Wether the symbol is a local_symbol. */ 27 unsigned int sy_local_symbol : 1; 28 29 /* Wether symbol has been written. */ 30 unsigned int sy_written : 1; 31 32 /* Whether symbol value has been completely resolved (used during 33 final pass over symbol table). */ 34 unsigned int sy_resolved : 1; 35 36 /* Whether the symbol value is currently being resolved (used to 37 detect loops in symbol dependencies). */ 38 unsigned int sy_resolving : 1; 39 40 /* Whether the symbol value is used in a reloc. This is used to 41 ensure that symbols used in relocs are written out, even if they 42 are local and would otherwise not be. */ 43 unsigned int sy_used_in_reloc : 1; 44 45 /* Whether the symbol is used as an operand or in an expression. 46 NOTE: Not all the backends keep this information accurate; 47 backends which use this bit are responsible for setting it when 48 a symbol is used in backend routines. */ 49 unsigned int sy_used : 1; 50 51 /* Whether the symbol can be re-defined. */ 52 unsigned int sy_volatile : 1; 53 54 /* Whether the symbol is a forward reference. */ 55 unsigned int sy_forward_ref : 1; 56 57 /* This is set if the symbol is defined in an MRI common section. 58 We handle such sections as single common symbols, so symbols 59 defined within them must be treated specially by the relocation 60 routines. */ 61 unsigned int sy_mri_common : 1; 62 63 /* This is set if the symbol is set with a .weakref directive. */ 64 unsigned int sy_weakrefr : 1; 65 66 /* This is set when the symbol is referenced as part of a .weakref 67 directive, but only if the symbol was not in the symbol table 68 before. It is cleared as soon as any direct reference to the 69 symbol is present. */ 70 unsigned int sy_weakrefd : 1; 71 }; 72 73 /* The information we keep for a symbol. Note that the symbol table 74 holds pointers both to this and to local_symbol structures. See 75 below. */ 76 77 struct symbol 78 { 79 /* Symbol flags. */ 80 struct symbol_flags sy_flags; 81 82 /* BFD symbol */ 83 asymbol *bsym; 84 85 /* The value of the symbol. */ 86 expressionS sy_value; 87 88 /* Forwards and (optionally) backwards chain pointers. */ 89 struct symbol *sy_next; 90 struct symbol *sy_previous; 91 92 /* Pointer to the frag this symbol is attached to, if any. 93 Otherwise, NULL. */ 94 struct frag *sy_frag; 95 96 #ifdef OBJ_SYMFIELD_TYPE 97 OBJ_SYMFIELD_TYPE sy_obj; 98 #endif 99 100 #ifdef TC_SYMFIELD_TYPE 101 TC_SYMFIELD_TYPE sy_tc; 102 #endif 103 104 #ifdef TARGET_SYMBOL_FIELDS 105 TARGET_SYMBOL_FIELDS 106 #endif 107 }; 108 109 /* A pointer in the symbol may point to either a complete symbol 110 (struct symbol above) or to a local symbol (struct local_symbol 111 defined here). The symbol code can detect the case by examining 112 the first field. It is always NULL for a local symbol. 113 114 We do this because we ordinarily only need a small amount of 115 information for a local symbol. The symbol table takes up a lot of 116 space, and storing less information for a local symbol can make a 117 big difference in assembler memory usage when assembling a large 118 file. */ 119 120 struct local_symbol 121 { 122 /* Symbol flags. Only sy_local_symbol and sy_resolved are relevant. */ 123 struct symbol_flags lsy_flags; 124 125 /* The symbol section. This also serves as a flag. If this is 126 reg_section, then this symbol has been converted into a regular 127 symbol, and lsy_sym points to it. */ 128 segT lsy_section; 129 130 /* The symbol name. */ 131 const char *lsy_name; 132 133 /* The symbol frag or the real symbol, depending upon the value in 134 lsy_section. */ 135 union 136 { 137 fragS *lsy_frag; 138 symbolS *lsy_sym; 139 } u; 140 141 /* The value of the symbol. */ 142 valueT lsy_value; 143 144 #ifdef TC_LOCAL_SYMFIELD_TYPE 145 TC_LOCAL_SYMFIELD_TYPE lsy_tc; 146 #endif 147 }; 148 149 #define local_symbol_converted_p(l) ((l)->lsy_section == reg_section) 150 #define local_symbol_mark_converted(l) ((l)->lsy_section = reg_section) 151 #define local_symbol_resolved_p(l) ((l)->lsy_flags.sy_resolved) 152 #define local_symbol_mark_resolved(l) ((l)->lsy_flags.sy_resolved = 1) 153 #define local_symbol_get_frag(l) ((l)->u.lsy_frag) 154 #define local_symbol_set_frag(l, f) ((l)->u.lsy_frag = (f)) 155 #define local_symbol_get_real_symbol(l) ((l)->u.lsy_sym) 156 #define local_symbol_set_real_symbol(l, s) ((l)->u.lsy_sym = (s)) 157 158 #endif /* __struc_symbol_h__ */ 159
