1/* write.h
2   Copyright 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1999, 2000, 2001,
3   2002, 2003, 2005, 2006, 2007
4   Free Software Foundation, Inc.
5
6   This file is part of GAS, the GNU Assembler.
7
8   GAS is free software; you can redistribute it and/or modify
9   it under the terms of the GNU General Public License as published by
10   the Free Software Foundation; either version 2, or (at your option)
11   any later version.
12
13   GAS is distributed in the hope that it will be useful,
14   but WITHOUT ANY WARRANTY; without even the implied warranty of
15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16   GNU General Public License for more details.
17
18   You should have received a copy of the GNU General Public License
19   along with GAS; see the file COPYING.  If not, write to the Free
20   Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
21   02110-1301, USA.  */
22
23#ifndef __write_h__
24#define __write_h__
25
26/* This is the name of a fake symbol which will never appear in the
27   assembler output.  S_IS_LOCAL detects it because of the \001.  */
28#ifndef FAKE_LABEL_NAME
29#define FAKE_LABEL_NAME "L0\001"
30#endif
31
32#include "bit_fix.h"
33
34/*
35 * FixSs may be built up in any order.
36 */
37
38struct fix
39{
40  /* These small fields are grouped together for compactness of
41     this structure, and efficiency of access on some architectures.  */
42
43  /* Is this a pc-relative relocation?  */
44  unsigned fx_pcrel : 1;
45
46  /* Is this value an immediate displacement?  */
47  /* Only used on ns32k; merge it into TC_FIX_TYPE sometime.  */
48  unsigned fx_im_disp : 2;
49
50  /* Some bits for the CPU specific code.  */
51  unsigned fx_tcbit : 1;
52  unsigned fx_tcbit2 : 1;
53
54  /* Has this relocation already been applied?  */
55  unsigned fx_done : 1;
56
57  /* Suppress overflow complaints on large addends.  This is used
58     in the PowerPC ELF config to allow large addends on the
59     BFD_RELOC_{LO16,HI16,HI16_S} relocations.
60
61     @@ Can this be determined from BFD?  */
62  unsigned fx_no_overflow : 1;
63
64  /* The value is signed when checking for overflow.  */
65  unsigned fx_signed : 1;
66
67  /* pc-relative offset adjust (only used by m68k and m68hc11) */
68  char fx_pcrel_adjust;
69
70  /* How many bytes are involved? */
71  unsigned char fx_size;
72
73  /* Which frag does this fix apply to?  */
74  fragS *fx_frag;
75
76  /* Where is the first byte to fix up?  */
77  long fx_where;
78
79  /* NULL or Symbol whose value we add in.  */
80  symbolS *fx_addsy;
81
82  /* NULL or Symbol whose value we subtract.  */
83  symbolS *fx_subsy;
84
85  /* Absolute number we add in.  */
86  valueT fx_offset;
87
88  /* The value of dot when the fixup expression was parsed.  */
89  addressT fx_dot_value;
90
91  /* Next fixS in linked list, or NULL.  */
92  struct fix *fx_next;
93
94  /* If NULL, no bitfix's to do.  */
95  /* Only i960-coff and ns32k use this, and i960-coff stores an
96     integer.  This can probably be folded into tc_fix_data, below.
97     @@ Alpha also uses it, but only to disable certain relocation
98     processing.  */
99  bit_fixS *fx_bit_fixP;
100
101  bfd_reloc_code_real_type fx_r_type;
102
103  /* This field is sort of misnamed.  It appears to be a sort of random
104     scratch field, for use by the back ends.  The main gas code doesn't
105     do anything but initialize it to zero.  The use of it does need to
106     be coordinated between the cpu and format files, though.  E.g., some
107     coff targets pass the `addend' field from the cpu file via this
108     field.  I don't know why the `fx_offset' field above can't be used
109     for that; investigate later and document. KR  */
110  valueT fx_addnumber;
111
112  /* The location of the instruction which created the reloc, used
113     in error messages.  */
114  char *fx_file;
115  unsigned fx_line;
116
117#ifdef USING_CGEN
118  struct {
119    /* CGEN_INSN entry for this instruction.  */
120    const struct cgen_insn *insn;
121    /* Target specific data, usually reloc number.  */
122    int opinfo;
123    /* Which ifield this fixup applies to. */
124    struct cgen_maybe_multi_ifield * field;
125    /* is this field is the MSB field in a set? */
126    int msb_field_p;
127  } fx_cgen;
128#endif
129
130#ifdef TC_FIX_TYPE
131  /* Location where a backend can attach additional data
132     needed to perform fixups.  */
133  TC_FIX_TYPE tc_fix_data;
134#endif
135};
136
137typedef struct fix fixS;
138
139struct reloc_list
140{
141  struct reloc_list *next;
142  union
143  {
144    struct
145    {
146      symbolS *offset_sym;
147      reloc_howto_type *howto;
148      symbolS *sym;
149      bfd_vma addend;
150    } a;
151    struct
152    {
153      asection *sec;
154      asymbol *s;
155      arelent r;
156    } b;
157  } u;
158  char *file;
159  unsigned int line;
160};
161
162extern int finalize_syms;
163extern symbolS *abs_section_sym;
164extern addressT dot_value;
165extern struct reloc_list* reloc_list;
166
167extern void append (char **charPP, char *fromP, unsigned long length);
168extern void record_alignment (segT seg, int align);
169extern int get_recorded_alignment (segT seg);
170extern void subsegs_finish (void);
171extern void write_object_file (void);
172extern long relax_frag (segT, fragS *, long);
173extern int relax_segment (struct frag *, segT, int);
174extern void number_to_chars_littleendian (char *, valueT, int);
175extern void number_to_chars_bigendian (char *, valueT, int);
176extern fixS *fix_new
177  (fragS * frag, int where, int size, symbolS * add_symbol,
178   offsetT offset, int pcrel, bfd_reloc_code_real_type r_type);
179extern fixS *fix_new_exp
180  (fragS * frag, int where, int size, expressionS *exp, int pcrel,
181   bfd_reloc_code_real_type r_type);
182extern void write_print_statistics (FILE *);
183
184#endif /* __write_h__ */
185