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
29struct 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
108struct 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