| 1 | /* struct_symbol.h - Internal symbol structure |
| 2 | Copyright (C) 1987-2017 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 | /* Whether the symbol is a local_symbol. */ |
| 27 | unsigned int sy_local_symbol : 1; |
| 28 | |
| 29 | /* Weather 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__ */ |