1/* write.h
2   Copyright (C) 1987-2017 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 3, 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, 51 Franklin Street - Fifth Floor, Boston, MA
19   02110-1301, USA.  */
20
21#ifndef __write_h__
22#define __write_h__
23
24/* This is the name of a fake symbol which will never appear in the
25   assembler output.  S_IS_LOCAL detects it because of the \001.  */
26#ifndef FAKE_LABEL_NAME
27#define FAKE_LABEL_NAME "L0\001"
28#endif
29
30#include "bit_fix.h"
31
32/*
33 * FixSs may be built up in any order.
34 */
35
36struct fix
37{
38  /* These small fields are grouped together for compactness of
39     this structure, and efficiency of access on some architectures.  */
40
41  /* Is this a pc-relative relocation?  */
42  unsigned fx_pcrel : 1;
43
44  /* Is this value an immediate displacement?  */
45  /* Only used on ns32k; merge it into TC_FIX_TYPE sometime.  */
46  unsigned fx_im_disp : 2;
47
48  /* Some bits for the CPU specific code.  */
49  unsigned fx_tcbit : 1;
50  unsigned fx_tcbit2 : 1;
51
52  /* Has this relocation already been applied?  */
53  unsigned fx_done : 1;
54
55  /* Suppress overflow complaints on large addends.  This is used
56     in the PowerPC ELF config to allow large addends on the
57     BFD_RELOC_{LO16,HI16,HI16_S} relocations.
58
59     @@ Can this be determined from BFD?  */
60  unsigned fx_no_overflow : 1;
61
62  /* The value is signed when checking for overflow.  */
63  unsigned fx_signed : 1;
64
65  /* pc-relative offset adjust (only used by some CPU specific code) */
66  signed char fx_pcrel_adjust;
67
68  /* How many bytes are involved? */
69  unsigned char fx_size;
70
71  /* Which frag does this fix apply to?  */
72  fragS *fx_frag;
73
74  /* Where is the first byte to fix up?  */
75  long fx_where;
76
77  /* NULL or Symbol whose value we add in.  */
78  symbolS *fx_addsy;
79
80  /* NULL or Symbol whose value we subtract.  */
81  symbolS *fx_subsy;
82
83  /* Absolute number we add in.  */
84  valueT fx_offset;
85
86  /* The value of dot when the fixup expression was parsed.  */
87  addressT fx_dot_value;
88
89  /* The frag fx_dot_value is based on.  */
90  fragS *fx_dot_frag;
91
92  /* Next fixS in linked list, or NULL.  */
93  struct fix *fx_next;
94
95  /* If NULL, no bitfix's to do.  */
96  /* Only i960-coff and ns32k use this, and i960-coff stores an
97     integer.  This can probably be folded into tc_fix_data, below.
98     @@ Alpha also uses it, but only to disable certain relocation
99     processing.  */
100  bit_fixS *fx_bit_fixP;
101
102  bfd_reloc_code_real_type fx_r_type;
103
104  /* This field is sort of misnamed.  It appears to be a sort of random
105     scratch field, for use by the back ends.  The main gas code doesn't
106     do anything but initialize it to zero.  The use of it does need to
107     be coordinated between the cpu and format files, though.  E.g., some
108     coff targets pass the `addend' field from the cpu file via this
109     field.  I don't know why the `fx_offset' field above can't be used
110     for that; investigate later and document. KR  */
111  valueT fx_addnumber;
112
113  /* The location of the instruction which created the reloc, used
114     in error messages.  */
115  const char *fx_file;
116  unsigned fx_line;
117
118#ifdef USING_CGEN
119  struct {
120    /* CGEN_INSN entry for this instruction.  */
121    const struct cgen_insn *insn;
122    /* Target specific data, usually reloc number.  */
123    int opinfo;
124    /* Which ifield this fixup applies to. */
125    struct cgen_maybe_multi_ifield * field;
126    /* is this field is the MSB field in a set? */
127    int msb_field_p;
128  } fx_cgen;
129#endif
130
131#ifdef TC_FIX_TYPE
132  /* Location where a backend can attach additional data
133     needed to perform fixups.  */
134  TC_FIX_TYPE tc_fix_data;
135#endif
136};
137
138typedef struct fix fixS;
139
140struct reloc_list
141{
142  struct reloc_list *next;
143  union
144  {
145    struct
146    {
147      symbolS *offset_sym;
148      reloc_howto_type *howto;
149      symbolS *sym;
150      bfd_vma addend;
151    } a;
152    struct
153    {
154      asection *sec;
155      asymbol *s;
156      arelent r;
157    } b;
158  } u;
159  const char *file;
160  unsigned int line;
161};
162
163extern int finalize_syms;
164extern symbolS *abs_section_sym;
165extern addressT dot_value;
166extern fragS *dot_frag;
167extern struct reloc_list* reloc_list;
168
169extern void append (char **, char *, unsigned long);
170extern void record_alignment (segT, unsigned);
171extern int get_recorded_alignment (segT);
172extern void write_object_file (void);
173extern long relax_frag (segT, fragS *, long);
174extern int relax_segment (struct frag *, segT, int);
175extern void number_to_chars_littleendian (char *, valueT, int);
176extern void number_to_chars_bigendian (char *, valueT, int);
177extern fixS *fix_new
178  (fragS * frag, int where, int size, symbolS * add_symbol,
179   offsetT offset, int pcrel, bfd_reloc_code_real_type r_type);
180extern fixS *fix_at_start
181  (fragS * frag, int size, symbolS * add_symbol,
182   offsetT offset, int pcrel, bfd_reloc_code_real_type r_type);
183extern fixS *fix_new_exp
184  (fragS * frag, int where, int size, expressionS *exp, int pcrel,
185   bfd_reloc_code_real_type r_type);
186extern void write_print_statistics (FILE *);
187
188#endif /* __write_h__ */
189