gas/struc-symbol.h

   1 /* struct_symbol.h - Internal symbol structure
   2    Copyright (C) 1987, 92, 93, 94, 95, 98, 99, 2000
   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, 59 Temple Place - Suite 330, Boston, MA
  20    02111-1307, 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 #ifdef BFD_ASSEMBLER
  32   /* BFD symbol */
  33   asymbol *bsym;
  34 #else
  35   /* The (4-origin) position of sy_name in the symbol table of the object
  36      file.  This will be 0 for (nameless) .stabd symbols.
  37
  38      Not used until write_object_file() time.  */
  39   unsigned long sy_name_offset;
  40
  41   /* What we write in .o file (if permitted).  */
  42   obj_symbol_type sy_symbol;
  43
  44   /* The 24 bit symbol number.  Symbol numbers start at 0 and are unsigned.  */
  45   long sy_number;
  46 #endif
  47
  48   /* The value of the symbol.  */
  49   expressionS sy_value;
  50
  51   /* Forwards and (optionally) backwards chain pointers.  */
  52   struct symbol *sy_next;
  53 #ifdef SYMBOLS_NEED_BACKPOINTERS
  54   struct symbol *sy_previous;
  55 #endif /* SYMBOLS_NEED_BACKPOINTERS */
  56
  57   /* Pointer to the frag this symbol is attached to, if any.
  58      Otherwise, NULL.  */
  59   struct frag *sy_frag;
  60
  61   unsigned int written : 1;
  62   /* Whether symbol value has been completely resolved (used during
  63      final pass over symbol table).  */
  64   unsigned int sy_resolved : 1;
  65   /* Whether the symbol value is currently being resolved (used to
  66      detect loops in symbol dependencies).  */
  67   unsigned int sy_resolving : 1;
  68   /* Whether the symbol value is used in a reloc.  This is used to
  69      ensure that symbols used in relocs are written out, even if they
  70      are local and would otherwise not be.  */
  71   unsigned int sy_used_in_reloc : 1;
  72
  73   /* Whether the symbol is used as an operand or in an expression.
  74      NOTE:  Not all the backends keep this information accurate;
  75      backends which use this bit are responsible for setting it when
  76      a symbol is used in backend routines.  */
  77   unsigned int sy_used : 1;
  78
  79   /* This is set if the symbol is defined in an MRI common section.
  80      We handle such sections as single common symbols, so symbols
  81      defined within them must be treated specially by the relocation
  82      routines.  */
  83   unsigned int sy_mri_common : 1;
  84
  85 #ifdef OBJ_SYMFIELD_TYPE
  86   OBJ_SYMFIELD_TYPE sy_obj;
  87 #endif
  88
  89 #ifdef TC_SYMFIELD_TYPE
  90   TC_SYMFIELD_TYPE sy_tc;
  91 #endif
  92 };
  93
  94 #ifdef BFD_ASSEMBLER
  95
  96 /* A pointer in the symbol may point to either a complete symbol
  97    (struct symbol above) or to a local symbol (struct local_symbol
  98    defined here).  The symbol code can detect the case by examining
  99    the first field.  It is always NULL for a local symbol.
 100
 101    We do this because we ordinarily only need a small amount of
 102    information for a local symbol.  The symbol table takes up a lot of
 103    space, and storing less information for a local symbol can make a
 104    big difference in assembler memory usage when assembling a large
 105    file.  */
 106
 107 struct local_symbol
 108 {
 109   /* This pointer is always NULL to indicate that this is a local
 110      symbol.  */
 111   asymbol *lsy_marker;
 112
 113   /* The symbol section.  This also serves as a flag.  If this is
 114      reg_section, then this symbol has been converted into a regular
 115      symbol, and sy_sym points to it.  */
 116   segT lsy_section;
 117
 118   /* The symbol name.  */
 119   const char *lsy_name;
 120
 121   /* The symbol frag or the real symbol, depending upon the value in
 122      sy_section.  If the symbol has been fully resolved, lsy_frag is
 123      set to NULL.  */
 124   union
 125   {
 126     fragS *lsy_frag;
 127     symbolS *lsy_sym;
 128   } u;
 129
 130   /* The offset within the frag.  */
 131   valueT lsy_offset;
 132 };
 133
 134 #define local_symbol_converted_p(l) ((l)->lsy_section == reg_section)
 135 #define local_symbol_mark_converted(l) ((l)->lsy_section = reg_section)
 136 #define local_symbol_resolved_p(l) ((l)->u.lsy_frag == NULL)
 137 #define local_symbol_mark_resolved(l) ((l)->u.lsy_frag = NULL)
 138 #define local_symbol_get_frag(l) ((l)->u.lsy_frag)
 139 #define local_symbol_set_frag(l, f) ((l)->u.lsy_frag = (f))
 140 #define local_symbol_get_real_symbol(l) ((l)->u.lsy_sym)
 141 #define local_symbol_set_real_symbol(l, s) ((l)->u.lsy_sym = (s))
 142
 143 #endif /* BFD_ASSEMBLER */
 144
 145 #endif /* __struc_symbol_h__ */