obj-aout.h revision 130561 
1/* obj-aout.h, a.out object file format for gas, the assembler.
2   Copyright 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 2000,
3   2002, 2003 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
9   published by the Free Software Foundation; either version 2,
10   or (at your option) any later version.
11
12   GAS is distributed in the hope that it will be useful, but
13   WITHOUT ANY WARRANTY; without even the implied warranty of
14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
15   the 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/* Tag to validate a.out object file format processing */
23#define OBJ_AOUT 1
24
25#include "targ-cpu.h"
26
27#ifdef BFD_ASSEMBLER
28
29#include "bfd/libaout.h"
30
31#define OUTPUT_FLAVOR bfd_target_aout_flavour
32
33#else /* ! BFD_ASSEMBLER */
34
35#ifndef VMS
36#include "aout_gnu.h"		/* Needed to define struct nlist. Sigh.  */
37#else
38#include "a_out.h"
39#endif
40
41#ifndef AOUT_MACHTYPE
42#define AOUT_MACHTYPE 0
43#endif /* AOUT_MACHTYPE */
44
45extern const short seg_N_TYPE[];
46extern const segT N_TYPE_seg[];
47
48#ifndef DEFAULT_MAGIC_NUMBER_FOR_OBJECT_FILE
49#define DEFAULT_MAGIC_NUMBER_FOR_OBJECT_FILE	(OMAGIC)
50#endif /* DEFAULT_MAGIC_NUMBER_FOR_OBJECT_FILE */
51
52#endif /* ! BFD_ASSEMBLER */
53
54extern const pseudo_typeS aout_pseudo_table[];
55
56#ifndef obj_pop_insert
57#define obj_pop_insert() pop_insert (aout_pseudo_table)
58#endif
59
60/* SYMBOL TABLE */
61/* Symbol table entry data type */
62
63typedef struct nlist obj_symbol_type;	/* Symbol table entry */
64
65/* Symbol table macros and constants */
66
67#ifdef BFD_ASSEMBLER
68
69#define S_SET_OTHER(S,V) \
70  (aout_symbol (symbol_get_bfdsym (S))->other = (V))
71#define S_SET_TYPE(S,T) \
72  (aout_symbol (symbol_get_bfdsym (S))->type = (T))
73#define S_SET_DESC(S,D)	\
74  (aout_symbol (symbol_get_bfdsym (S))->desc = (D))
75#define S_GET_OTHER(S) \
76  (aout_symbol (symbol_get_bfdsym (S))->other)
77#define S_GET_TYPE(S) \
78  (aout_symbol (symbol_get_bfdsym (S))->type)
79#define S_GET_DESC(S) \
80  (aout_symbol (symbol_get_bfdsym (S))->desc)
81
82asection *text_section, *data_section, *bss_section;
83
84#define obj_frob_symbol(S,PUNT)	obj_aout_frob_symbol (S, &PUNT)
85#define obj_frob_file_before_fix() obj_aout_frob_file_before_fix ()
86extern void obj_aout_frob_symbol PARAMS ((symbolS *, int *));
87extern void obj_aout_frob_file_before_fix PARAMS ((void));
88
89#define obj_sec_sym_ok_for_reloc(SEC)	(1)
90
91#else
92
93/* We use the sy_obj field to record whether a symbol is weak.  */
94#define OBJ_SYMFIELD_TYPE char
95
96/*
97 *  Macros to extract information from a symbol table entry.
98 *  This syntactic indirection allows independence regarding a.out or coff.
99 *  The argument (s) of all these macros is a pointer to a symbol table entry.
100 */
101
102/* True if the symbol is external */
103#define S_IS_EXTERNAL(s)	((s)->sy_symbol.n_type & N_EXT)
104
105/* True if symbol has been defined, ie is in N_{TEXT,DATA,BSS,ABS} or N_EXT */
106#define S_IS_DEFINED(s) \
107  (S_GET_TYPE (s) != N_UNDF || S_GET_DESC (s) != 0)
108
109#define S_IS_COMMON(s) \
110  (S_GET_TYPE (s) == N_UNDF && S_GET_VALUE (s) != 0)
111
112/* Return true for symbols that should not be reduced to section
113   symbols or eliminated from expressions, because they may be
114   overridden by the linker.  */
115#define S_FORCE_RELOC(s, strict) \
116  (!SEG_NORMAL (S_GET_SEGMENT (s)))
117
118#define S_IS_REGISTER(s)	((s)->sy_symbol.n_type == N_REGISTER)
119
120/* True if a debug special symbol entry */
121#define S_IS_DEBUG(s)		((s)->sy_symbol.n_type & N_STAB)
122/* True if a symbol is local symbol name */
123#define S_IS_LOCAL(s) 					\
124  ((S_GET_NAME (s) 					\
125    && !S_IS_DEBUG (s) 					\
126    && (strchr (S_GET_NAME (s), '\001') != NULL		\
127        || strchr (S_GET_NAME (s), '\002') != NULL	\
128        || (S_LOCAL_NAME(s) && !flag_keep_locals)))	\
129   || (flag_strip_local_absolute			\
130       && ! S_IS_EXTERNAL(s)				\
131       && S_GET_SEGMENT (s) == absolute_section))
132/* True if a symbol is not defined in this file */
133#define S_IS_EXTERN(s)		((s)->sy_symbol.n_type & N_EXT)
134/* True if the symbol has been generated because of a .stabd directive */
135#define S_IS_STABD(s)		(S_GET_NAME(s) == (char *)0)
136
137/* Accessors */
138/* The name of the symbol */
139#define S_GET_NAME(s)		((s)->sy_symbol.n_un.n_name)
140/* The pointer to the string table */
141#define S_GET_OFFSET(s)		((s)->sy_symbol.n_un.n_strx)
142/* The type of the symbol */
143#define S_GET_TYPE(s)		((s)->sy_symbol.n_type & N_TYPE)
144/* The numeric value of the segment */
145#define S_GET_SEGMENT(s)	(N_TYPE_seg[S_GET_TYPE(s)])
146/* The n_other expression value */
147#define S_GET_OTHER(s)		((s)->sy_symbol.n_other)
148/* The n_desc expression value */
149#define S_GET_DESC(s)		((s)->sy_symbol.n_desc)
150/* Whether the symbol is weak.  */
151#define S_GET_WEAK(s)		((s)->sy_obj)
152
153/* Modifiers */
154/* Assume that a symbol cannot be simultaneously in more than on segment */
155/* set segment */
156#define S_SET_SEGMENT(s,seg)	((s)->sy_symbol.n_type &= ~N_TYPE,(s)->sy_symbol.n_type|=SEGMENT_TO_SYMBOL_TYPE(seg))
157/* The symbol is external */
158#define S_SET_EXTERNAL(s)	((s)->sy_symbol.n_type |= N_EXT)
159/* The symbol is not external */
160#define S_CLEAR_EXTERNAL(s)	((s)->sy_symbol.n_type &= ~N_EXT)
161/* Set the name of the symbol */
162#define S_SET_NAME(s,v)		((s)->sy_symbol.n_un.n_name = (v))
163/* Set the offset in the string table */
164#define S_SET_OFFSET(s,v)	((s)->sy_symbol.n_un.n_strx = (v))
165/* Set the n_type field */
166#define S_SET_TYPE(s,t)		((s)->sy_symbol.n_type = (t))
167/* Set the n_other expression value */
168#define S_SET_OTHER(s,v)	((s)->sy_symbol.n_other = (v))
169/* Set the n_desc expression value */
170#define S_SET_DESC(s,v)		((s)->sy_symbol.n_desc = (v))
171/* Mark the symbol as weak.  This causes n_type to be adjusted when
172   the symbol is written out.  */
173#define S_SET_WEAK(s)		((s)->sy_obj = 1)
174
175/* File header macro and type definition */
176
177#define H_GET_FILE_SIZE(h)	(H_GET_HEADER_SIZE(h) \
178				 + H_GET_TEXT_SIZE(h) \
179				 + H_GET_DATA_SIZE(h) \
180				 + H_GET_SYMBOL_TABLE_SIZE(h) \
181				 + H_GET_TEXT_RELOCATION_SIZE(h) \
182				 + H_GET_DATA_RELOCATION_SIZE(h) \
183				 + H_GET_STRING_SIZE(h))
184
185#define H_GET_HEADER_SIZE(h)		(EXEC_BYTES_SIZE)
186#define H_GET_TEXT_SIZE(h)		((h)->header.a_text)
187#define H_GET_DATA_SIZE(h)		((h)->header.a_data)
188#define H_GET_BSS_SIZE(h)		((h)->header.a_bss)
189#define H_GET_TEXT_RELOCATION_SIZE(h)	((h)->header.a_trsize)
190#define H_GET_DATA_RELOCATION_SIZE(h)	((h)->header.a_drsize)
191#define H_GET_SYMBOL_TABLE_SIZE(h)	((h)->header.a_syms)
192#define H_GET_ENTRY_POINT(h)		((h)->header.a_entry)
193#define H_GET_STRING_SIZE(h)		((h)->string_table_size)
194#define H_GET_LINENO_SIZE(h)		(0)
195
196#define H_GET_DYNAMIC(h)		((h)->header.a_info >> 31)
197#define H_GET_VERSION(h)		(((h)->header.a_info >> 24) & 0x7f)
198#define H_GET_MACHTYPE(h)		(((h)->header.a_info >> 16) & 0xff)
199#define H_GET_MAGIC_NUMBER(h)		((h)->header.a_info & 0xffff)
200
201#define H_SET_DYNAMIC(h,v)		((h)->header.a_info = (((v) << 31) \
202							       | (H_GET_VERSION(h) << 24) \
203							       | (H_GET_MACHTYPE(h) << 16) \
204							       | (H_GET_MAGIC_NUMBER(h))))
205
206#define H_SET_VERSION(h,v)		((h)->header.a_info = ((H_GET_DYNAMIC(h) << 31) \
207							       | ((v) << 24) \
208							       | (H_GET_MACHTYPE(h) << 16) \
209							       | (H_GET_MAGIC_NUMBER(h))))
210
211#define H_SET_MACHTYPE(h,v)		((h)->header.a_info = ((H_GET_DYNAMIC(h) << 31) \
212							       | (H_GET_VERSION(h) << 24) \
213							       | ((v) << 16) \
214							       | (H_GET_MAGIC_NUMBER(h))))
215
216#define H_SET_MAGIC_NUMBER(h,v)		((h)->header.a_info = ((H_GET_DYNAMIC(h) << 31) \
217							       | (H_GET_VERSION(h) << 24) \
218							       | (H_GET_MACHTYPE(h) << 16) \
219							       | ((v))))
220
221#define H_SET_TEXT_SIZE(h,v)		((h)->header.a_text = md_section_align(SEG_TEXT, (v)))
222#define H_SET_DATA_SIZE(h,v)		((h)->header.a_data = md_section_align(SEG_DATA, (v)))
223#define H_SET_BSS_SIZE(h,v)		((h)->header.a_bss = md_section_align(SEG_BSS, (v)))
224
225#define H_SET_RELOCATION_SIZE(h,t,d)	(H_SET_TEXT_RELOCATION_SIZE((h),(t)),\
226					 H_SET_DATA_RELOCATION_SIZE((h),(d)))
227
228#define H_SET_TEXT_RELOCATION_SIZE(h,v)	((h)->header.a_trsize = (v))
229#define H_SET_DATA_RELOCATION_SIZE(h,v)	((h)->header.a_drsize = (v))
230#define H_SET_SYMBOL_TABLE_SIZE(h,v)	((h)->header.a_syms = (v) * 12)
231
232#define H_SET_ENTRY_POINT(h,v)		((h)->header.a_entry = (v))
233#define H_SET_STRING_SIZE(h,v)		((h)->string_table_size = (v))
234
235typedef struct
236  {
237    struct exec header;		/* a.out header */
238    long string_table_size;	/* names + '\0' + sizeof (int) */
239  }
240
241object_headers;
242
243/* line numbering stuff.  */
244#define OBJ_EMIT_LINENO(a, b, c)	{;}
245
246struct fix;
247void tc_aout_fix_to_chars PARAMS ((char *where, struct fix *fixP, relax_addressT segment_address));
248
249#endif
250
251#define obj_read_begin_hook()	{;}
252#define obj_symbol_new_hook(s)	{;}
253
254#define EMIT_SECTION_SYMBOLS		0
255
256#define AOUT_STABS
257