gas/struc-symbol.h

   1 /* struct_symbol.h - Internal symbol structure
   2    Copyright (C) 1987, 92, 93, 94, 95, 98, 1999 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 2, 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, 59 Temple Place - Suite 330, Boston, MA
  19    02111-1307, USA.  */
  20
  21 #ifndef __struc_symbol_h__
  22 #define __struc_symbol_h__
  23
  24 /* The information we keep for a symbol.  Note that the symbol table
  25    holds pointers both to this and to local_symbol structures.  See
  26    below.  */
  27
  28 struct symbol
  29 {
  30 #ifdef BFD_ASSEMBLER
  31   /* BFD symbol */
  32   asymbol *bsym;
  33 #else
  34   /* The (4-origin) position of sy_name in the symbol table of the object
  35      file.  This will be 0 for (nameless) .stabd symbols.
  36
  37      Not used until write_object_file() time. */
  38   unsigned long sy_name_offset;
  39
  40   /* What we write in .o file (if permitted).  */
  41   obj_symbol_type sy_symbol;
  42
  43   /* The 24 bit symbol number.  Symbol numbers start at 0 and are unsigned. */
  44   long sy_number;
  45 #endif
  46
  47   /* The value of the symbol.  */
  48   expressionS sy_value;
  49
  50   /* Forwards and (optionally) backwards chain pointers.  */
  51   struct symbol *sy_next;
  52 #ifdef SYMBOLS_NEED_BACKPOINTERS
  53   struct symbol *sy_previous;
  54 #endif /* SYMBOLS_NEED_BACKPOINTERS */
  55
  56   /* Pointer to the frag this symbol is attached to, if any.
  57      Otherwise, NULL.  */
  58   struct frag *sy_frag;
  59
  60   unsigned int written : 1;
  61   /* Whether symbol value has been completely resolved (used during
  62      final pass over symbol table).  */
  63   unsigned int sy_resolved : 1;
  64   /* Whether the symbol value is currently being resolved (used to
  65      detect loops in symbol dependencies).  */
  66   unsigned int sy_resolving : 1;
  67   /* Whether the symbol value is used in a reloc.  This is used to
  68      ensure that symbols used in relocs are written out, even if they
  69      are local and would otherwise not be.  */
  70   unsigned int sy_used_in_reloc : 1;
  71
  72   /* Whether the symbol is used as an operand or in an expression.
  73      NOTE:  Not all the backends keep this information accurate;
  74      backends which use this bit are responsible for setting it when
  75      a symbol is used in backend routines.  */
  76   unsigned int sy_used : 1;
  77
  78   /* This is set if the symbol is defined in an MRI common section.
  79      We handle such sections as single common symbols, so symbols
  80      defined within them must be treated specially by the relocation
  81      routines.  */
  82   unsigned int sy_mri_common : 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
  93 #ifdef BFD_ASSEMBLER
  94
  95 /* A pointer in the symbol may point to either a complete symbol
  96    (struct symbol above) or to a local symbol (struct local_symbol
  97    defined here).  The symbol code can detect the case by examining
  98    the first field.  It is always NULL for a local symbol.
  99
 100    We do this because we ordinarily only need a small amount of
 101    information for a local symbol.  The symbol table takes up a lot of
 102    space, and storing less information for a local symbol can make a
 103    big difference in assembler memory usage when assembling a large
 104    file.  */
 105
 106 struct local_symbol
 107 {
 108   /* This pointer is always NULL to indicate that this is a local
 109      symbol.  */
 110   asymbol *lsy_marker;
 111
 112   /* The symbol section.  This also serves as a flag.  If this is
 113      reg_section, then this symbol has been converted into a regular
 114      symbol, and sy_sym points to it.  */
 115   segT lsy_section;
 116
 117   /* The symbol name.  */
 118   const char *lsy_name;
 119
 120   /* The symbol frag or the real symbol, depending upon the value in
 121      sy_section.  If the symbol has been fully resolved, lsy_frag is
 122      set to NULL.  */
 123   union
 124   {
 125     fragS *lsy_frag;
 126     symbolS *lsy_sym;
 127   } u;
 128
 129   /* The offset within the frag.  */
 130   valueT lsy_offset;
 131 };
 132
 133 #define local_symbol_converted_p(l) ((l)->lsy_section == reg_section)
 134 #define local_symbol_mark_converted(l) ((l)->lsy_section = reg_section)
 135 #define local_symbol_resolved_p(l) ((l)->u.lsy_frag == NULL)
 136 #define local_symbol_mark_resolved(l) ((l)->u.lsy_frag = NULL)
 137 #define local_symbol_get_frag(l) ((l)->u.lsy_frag)
 138 #define local_symbol_set_frag(l, f) ((l)->u.lsy_frag = (f))
 139 #define local_symbol_get_real_symbol(l) ((l)->u.lsy_sym)
 140 #define local_symbol_set_real_symbol(l, s) ((l)->u.lsy_sym = (s))
 141
 142 #endif /* BFD_ASSEMBLER */
 143
 144 #endif /* __struc_symbol_h__ */
 145
 146 /* end of struc-symbol.h */