1 /* subsegs.h -> subsegs.c
2 Copyright (C) 1987-2022 Free Software Foundation, Inc.
4 This file is part of GAS, the GNU Assembler.
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)
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.
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
22 * For every sub-segment the user mentions in the ASsembler program,
23 * we make one struct frchain. Each sub-segment has exactly one struct frchain
26 * Struct frchain's are forward chained (in ascending order of sub-segment
27 * code number). The chain runs through frch_next of each subsegment.
28 * This makes it hard to find a subsegment's frags
29 * if programmer uses a lot of them. Most programs only use text0 and
30 * data0, so they don't suffer. At least this way:
31 * (1) There are no "arbitrary" restrictions on how many subsegments
33 * (2) Subsegments' frchain-s are (later) chained together in the order in
34 * which they are emitted for object file viz text then data.
36 * From each struct frchain dangles a chain of struct frags. The frags
37 * represent code fragments, for that sub-segment, forward chained.
44 struct frchain
/* control building of a frag chain */
45 { /* FRCH = FRagment CHain control */
46 struct frag
*frch_root
; /* 1st struct frag in chain, or NULL */
47 struct frag
*frch_last
; /* last struct frag in chain, or NULL */
48 struct frchain
*frch_next
; /* next in chain of struct frchain-s */
49 subsegT frch_subseg
; /* subsegment number of this chain */
50 fixS
*fix_root
; /* Root of fixups for this subsegment. */
51 fixS
*fix_tail
; /* Last fixup for this subsegment. */
52 struct obstack frch_obstack
; /* for objects in this frag chain */
53 fragS
*frch_frag_now
; /* frag_now for this subsegment */
54 struct frch_cfi_data
*frch_cfi_data
;
57 typedef struct frchain frchainS
;
59 /* Frchain we are assembling into now. That is, the current segment's
60 frag chain, even if it contains no (complete) frags. */
61 extern frchainS
*frchain_now
;
63 typedef struct segment_info_struct
{
65 unsigned int hadone
: 1;
67 /* This field is set if this is a .bss section which does not really
68 have any contents. Once upon a time a .bss section did not have
69 any frags, but that is no longer true. This field prevent the
70 SEC_HAS_CONTENTS flag from being set for the section even if
76 /* Fixups for this segment. This is only valid after the frchains
83 struct lineno_list
*lineno_list_head
;
84 struct lineno_list
*lineno_list_tail
;
86 /* Which BFD section does this gas segment correspond to? */
87 asection
*bfd_section
;
89 /* NULL, or pointer to the gas symbol that is the section symbol for
90 this section. sym->bsym and bfd_section->symbol should be the same. */
93 /* Used by dwarf2dbg.c for this section's line table entries. */
94 void *dwarf2_line_seg
;
97 /* Current size of section holding stabs strings. */
98 unsigned long stab_string_size
;
99 /* Initial frag for ELF. */
104 #ifdef NEED_LITERAL_POOL
105 unsigned long literal_pool_size
;
108 #ifdef TC_SEGMENT_INFO_TYPE
109 TC_SEGMENT_INFO_TYPE tc_segment_info_data
;
114 #define seg_info(sec) \
115 ((segment_info_type *) bfd_section_userdata (sec))
117 extern symbolS
*section_symbol (segT
);
119 extern void subsegs_print_statistics (FILE *);