1 /* struct_symbol.h - Internal symbol structure 2 Copyright 1987, 1992, 1993, 1994, 1995, 1998, 1999, 2000, 2001, 2005 3 Free Software Foundation, Inc. 4 5 This file is part of GAS, the GNU Assembler. 6 7 GAS is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 2, or (at your option) 10 any later version. 11 12 GAS is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with GAS; see the file COPYING. If not, write to the Free 19 Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA 20 02110-1301, USA. */ 21 22 #ifndef __struc_symbol_h__ 23 #define __struc_symbol_h__ 24 25 /* The information we keep for a symbol. Note that the symbol table 26 holds pointers both to this and to local_symbol structures. See 27 below. */ 28 29 struct symbol 30 { 31 /* BFD symbol */ 32 asymbol *bsym; 33 34 /* The value of the symbol. */ 35 expressionS sy_value; 36 37 /* Forwards and (optionally) backwards chain pointers. */ 38 struct symbol *sy_next; 39 struct symbol *sy_previous; 40 41 /* Pointer to the frag this symbol is attached to, if any. 42 Otherwise, NULL. */ 43 struct frag *sy_frag; 44 45 unsigned int written : 1; 46 /* Whether symbol value has been completely resolved (used during 47 final pass over symbol table). */ 48 unsigned int sy_resolved : 1; 49 /* Whether the symbol value is currently being resolved (used to 50 detect loops in symbol dependencies). */ 51 unsigned int sy_resolving : 1; 52 /* Whether the symbol value is used in a reloc. This is used to 53 ensure that symbols used in relocs are written out, even if they 54 are local and would otherwise not be. */ 55 unsigned int sy_used_in_reloc : 1; 56 57 /* Whether the symbol is used as an operand or in an expression. 58 NOTE: Not all the backends keep this information accurate; 59 backends which use this bit are responsible for setting it when 60 a symbol is used in backend routines. */ 61 unsigned int sy_used : 1; 62 63 /* Whether the symbol can be re-defined. */ 64 unsigned int sy_volatile : 1; 65 66 /* Whether the symbol is a forward reference. */ 67 unsigned int sy_forward_ref : 1; 68 69 /* This is set if the symbol is defined in an MRI common section. 70 We handle such sections as single common symbols, so symbols 71 defined within them must be treated specially by the relocation 72 routines. */ 73 unsigned int sy_mri_common : 1; 74 75 /* This is set if the symbol is set with a .weakref directive. */ 76 unsigned int sy_weakrefr : 1; 77 78 /* This is set when the symbol is referenced as part of a .weakref 79 directive, but only if the symbol was not in the symbol table 80 before. It is cleared as soon as any direct reference to the 81 symbol is present. */ 82 unsigned int sy_weakrefd : 1; 83 84 #ifdef OBJ_SYMFIELD_TYPE 85 OBJ_SYMFIELD_TYPE sy_obj; 86 #endif 87 88 #ifdef TC_SYMFIELD_TYPE 89 TC_SYMFIELD_TYPE sy_tc; 90 #endif 91 92 #ifdef TARGET_SYMBOL_FIELDS 93 TARGET_SYMBOL_FIELDS 94 #endif 95 }; 96 97 /* A pointer in the symbol may point to either a complete symbol 98 (struct symbol above) or to a local symbol (struct local_symbol 99 defined here). The symbol code can detect the case by examining 100 the first field. It is always NULL for a local symbol. 101 102 We do this because we ordinarily only need a small amount of 103 information for a local symbol. The symbol table takes up a lot of 104 space, and storing less information for a local symbol can make a 105 big difference in assembler memory usage when assembling a large 106 file. */ 107 108 struct local_symbol 109 { 110 /* This pointer is always NULL to indicate that this is a local 111 symbol. */ 112 asymbol *lsy_marker; 113 114 /* The symbol section. This also serves as a flag. If this is 115 reg_section, then this symbol has been converted into a regular 116 symbol, and lsy_sym points to it. */ 117 segT lsy_section; 118 119 /* The symbol name. */ 120 const char *lsy_name; 121 122 /* The symbol frag or the real symbol, depending upon the value in 123 lsy_section. If the symbol has been fully resolved, lsy_frag is 124 set to NULL. */ 125 union 126 { 127 fragS *lsy_frag; 128 symbolS *lsy_sym; 129 } u; 130 131 /* The value of the symbol. */ 132 valueT lsy_value; 133 134 #ifdef TC_LOCAL_SYMFIELD_TYPE 135 TC_LOCAL_SYMFIELD_TYPE lsy_tc; 136 #endif 137 }; 138 139 #define local_symbol_converted_p(l) ((l)->lsy_section == reg_section) 140 #define local_symbol_mark_converted(l) ((l)->lsy_section = reg_section) 141 #define local_symbol_resolved_p(l) ((l)->u.lsy_frag == NULL) 142 #define local_symbol_mark_resolved(l) ((l)->u.lsy_frag = NULL) 143 #define local_symbol_get_frag(l) ((l)->u.lsy_frag) 144 #define local_symbol_set_frag(l, f) ((l)->u.lsy_frag = (f)) 145 #define local_symbol_get_real_symbol(l) ((l)->u.lsy_sym) 146 #define local_symbol_set_real_symbol(l, s) ((l)->u.lsy_sym = (s)) 147 148 #endif /* __struc_symbol_h__ */ 149