1 /* dwarf2dbg.c - DWARF2 debug support
2 Copyright 1999, 2000, 2001 Free Software Foundation, Inc.
3 Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
5 This file is part of GAS, the GNU Assembler.
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)
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.
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
22 /* Logical line numbers can be controlled by the compiler via the
23 following two directives:
26 .loc FILENO LINENO [COLUMN]
28 FILENO is the filenumber. */
36 #ifdef HAVE_SYS_PARAM_H
37 #include <sys/param.h>
40 #define INT_MAX (int) (((unsigned) (-1)) >> 1)
46 #include "dwarf2dbg.h"
49 #include "elf/dwarf2.h"
51 /* Since we can't generate the prolog until the body is complete, we
52 use three different subsegments for .debug_line: one holding the
53 prolog, one for the directory and filename info, and one for the
54 body ("statement program"). */
59 /* First special line opcde - leave room for the standard opcodes.
60 Note: If you want to change this, you'll have to update the
61 "standard_opcode_lengths" table that is emitted below in
63 #define DWARF2_LINE_OPCODE_BASE 10
65 #ifndef DWARF2_LINE_BASE
66 /* Minimum line offset in a special line info. opcode. This value
67 was chosen to give a reasonable range of values. */
68 # define DWARF2_LINE_BASE -5
71 /* Range of line offsets in a special line info. opcode. */
72 #ifndef DWARF2_LINE_RANGE
73 # define DWARF2_LINE_RANGE 14
76 #ifndef DWARF2_LINE_MIN_INSN_LENGTH
77 /* Define the architecture-dependent minimum instruction length (in
78 bytes). This value should be rather too small than too big. */
79 # define DWARF2_LINE_MIN_INSN_LENGTH 1
82 /* Flag that indicates the initial value of the is_stmt_start flag.
83 In the present implementation, we do not mark any lines as
84 the beginning of a source statement, because that information
85 is not made available by the GCC front-end. */
86 #define DWARF2_LINE_DEFAULT_IS_STMT 1
88 /* Given a special op, return the line skip amount. */
89 #define SPECIAL_LINE(op) \
90 (((op) - DWARF2_LINE_OPCODE_BASE)%DWARF2_LINE_RANGE + DWARF2_LINE_BASE)
92 /* Given a special op, return the address skip amount (in units of
93 DWARF2_LINE_MIN_INSN_LENGTH. */
94 #define SPECIAL_ADDR(op) (((op) - DWARF2_LINE_OPCODE_BASE)/DWARF2_LINE_RANGE)
96 /* The maximum address skip amount that can be encoded with a special op. */
97 #define MAX_SPECIAL_ADDR_DELTA SPECIAL_ADDR(255)
100 struct line_entry
*next
;
103 struct dwarf2_line_info loc
;
107 struct line_subseg
*next
;
109 struct line_entry
*head
;
110 struct line_entry
**ptail
;
114 struct line_seg
*next
;
116 struct line_subseg
*head
;
121 /* Collects data for all line table entries during assembly. */
122 static struct line_seg
*all_segs
;
129 /* Table of files used by .debug_line. */
130 static struct file_entry
*files
;
131 static unsigned int files_in_use
;
132 static unsigned int files_allocated
;
134 /* True when we've seen a .loc directive recently. Used to avoid
135 doing work when there's nothing to do. */
136 static boolean loc_directive_seen
;
138 /* Current location as indicated by the most recent .loc directive. */
139 static struct dwarf2_line_info current
;
141 /* Fake label name. */
142 static char const fake_label_name
[] = ".L0\001";
144 /* The size of an address on the target. */
145 static unsigned int sizeof_address
;
147 static struct line_subseg
*get_line_subseg
PARAMS ((segT
, subsegT
));
148 static unsigned int get_filenum
PARAMS ((const char *));
149 static struct frag
*first_frag_for_seg
PARAMS ((segT
));
150 static struct frag
*last_frag_for_seg
PARAMS ((segT
));
151 static void out_byte
PARAMS ((int));
152 static void out_opcode
PARAMS ((int));
153 static void out_two
PARAMS ((int));
154 static void out_four
PARAMS ((int));
155 static void out_abbrev
PARAMS ((int, int));
156 static void out_uleb128
PARAMS ((addressT
));
157 static symbolS
*symbol_new_now
PARAMS ((void));
158 static void set_symbol_value_now
PARAMS ((symbolS
*));
159 static offsetT get_frag_fix
PARAMS ((fragS
*));
160 static void out_set_addr
PARAMS ((segT
, fragS
*, addressT
));
161 static int size_inc_line_addr
PARAMS ((int, addressT
));
162 static void emit_inc_line_addr
PARAMS ((int, addressT
, char *, int));
163 static void out_inc_line_addr
PARAMS ((int, addressT
));
164 static void relax_inc_line_addr
PARAMS ((int, segT
, fragS
*, addressT
,
166 static void process_entries
PARAMS ((segT
, struct line_entry
*));
167 static void out_file_list
PARAMS ((void));
168 static void out_debug_line
PARAMS ((segT
));
169 static void out_debug_aranges
PARAMS ((segT
, segT
));
170 static void out_debug_abbrev
PARAMS ((segT
));
171 static void out_debug_info
PARAMS ((segT
, segT
, segT
));
173 /* Find or create an entry for SEG+SUBSEG in ALL_SEGS. */
175 static struct line_subseg
*
176 get_line_subseg (seg
, subseg
)
180 static segT last_seg
;
181 static subsegT last_subseg
;
182 static struct line_subseg
*last_line_subseg
;
185 struct line_subseg
**pss
, *ss
;
187 if (seg
== last_seg
&& subseg
== last_subseg
)
188 return last_line_subseg
;
190 for (s
= all_segs
; s
; s
= s
->next
)
194 s
= (struct line_seg
*) xmalloc (sizeof (*s
));
201 for (pss
= &s
->head
; (ss
= *pss
) != NULL
; pss
= &ss
->next
)
203 if (ss
->subseg
== subseg
)
205 if (ss
->subseg
> subseg
)
209 ss
= (struct line_subseg
*) xmalloc (sizeof (*ss
));
213 ss
->ptail
= &ss
->head
;
218 last_subseg
= subseg
;
219 last_line_subseg
= ss
;
224 /* Record an entry for LOC ocurring at OFS within the current fragment. */
227 dwarf2_gen_line_info (ofs
, loc
)
229 struct dwarf2_line_info
*loc
;
231 struct line_subseg
*ss
;
232 struct line_entry
*e
;
234 /* Early out for as-yet incomplete location information. */
235 if (loc
->filenum
== 0 || loc
->line
== 0)
238 e
= (struct line_entry
*) xmalloc (sizeof (*e
));
244 ss
= get_line_subseg (now_seg
, now_subseg
);
246 ss
->ptail
= &e
->next
;
251 struct dwarf2_line_info
*line
;
253 if (debug_type
== DEBUG_DWARF2
)
256 as_where (&filename
, &line
->line
);
257 line
->filenum
= get_filenum (filename
);
259 line
->flags
= DWARF2_FLAG_BEGIN_STMT
;
265 /* Called for each machine instruction, or relatively atomic group of
266 machine instructions (ie built-in macro). The instruction or group
267 is SIZE bytes in length. If dwarf2 line number generation is called
268 for, emit a line statement appropriately. */
271 dwarf2_emit_insn (size
)
274 struct dwarf2_line_info loc
;
276 if (debug_type
!= DEBUG_DWARF2
&& ! loc_directive_seen
)
278 loc_directive_seen
= false;
281 dwarf2_gen_line_info (frag_now_fix () - size
, &loc
);
284 /* Get a .debug_line file number for FILENAME. */
287 get_filenum (filename
)
288 const char *filename
;
290 static unsigned int last_used
;
294 if (strcmp (filename
, files
[last_used
].filename
) == 0)
297 for (i
= 1; i
< files_in_use
; ++i
)
298 if (strcmp (filename
, files
[i
].filename
) == 0)
301 if (i
>= files_allocated
)
303 unsigned int old
= files_allocated
;
305 files_allocated
= i
+ 32;
306 files
= (struct file_entry
*)
307 xrealloc (files
, (i
+ 32) * sizeof (struct file_entry
));
309 memset (files
+ old
, 0, (i
+ 32 - old
) * sizeof (struct file_entry
));
312 files
[i
].filename
= xstrdup (filename
);
314 files_in_use
= i
+ 1;
320 /* Handle the .file directive. */
323 dwarf2_directive_file (dummy
)
324 int dummy ATTRIBUTE_UNUSED
;
330 /* Continue to accept a bare string and pass it off. */
332 if (*input_line_pointer
== '"')
338 num
= get_absolute_expression ();
339 filename
= demand_copy_C_string (&filename_len
);
340 demand_empty_rest_of_line ();
344 as_bad (_("file number less than one"));
348 if (num
< (int) files_in_use
&& files
[num
].filename
!= 0)
350 as_bad (_("file number %ld already allocated"), (long) num
);
354 if (num
>= (int) files_allocated
)
356 unsigned int old
= files_allocated
;
358 files_allocated
= num
+ 16;
359 files
= (struct file_entry
*)
360 xrealloc (files
, (num
+ 16) * sizeof (struct file_entry
));
362 /* Zero the new memory. */
363 memset (files
+ old
, 0, (num
+ 16 - old
) * sizeof (struct file_entry
));
366 files
[num
].filename
= filename
;
368 files_in_use
= num
+ 1;
372 dwarf2_directive_loc (dummy
)
373 int dummy ATTRIBUTE_UNUSED
;
375 offsetT filenum
, line
, column
;
377 filenum
= get_absolute_expression ();
379 line
= get_absolute_expression ();
381 column
= get_absolute_expression ();
382 demand_empty_rest_of_line ();
386 as_bad (_("file number less than one"));
389 if (filenum
>= (int) files_in_use
|| files
[filenum
].filename
== 0)
391 as_bad (_("unassigned file number %ld"), (long) filenum
);
395 current
.filenum
= filenum
;
397 current
.column
= column
;
398 current
.flags
= DWARF2_FLAG_BEGIN_STMT
;
400 loc_directive_seen
= true;
404 listing_source_line (line
);
409 first_frag_for_seg (seg
)
412 frchainS
*f
, *first
= NULL
;
414 for (f
= frchain_root
; f
; f
= f
->frch_next
)
415 if (f
->frch_seg
== seg
416 && (! first
|| first
->frch_subseg
> f
->frch_subseg
))
419 return first
? first
->frch_root
: NULL
;
423 last_frag_for_seg (seg
)
426 frchainS
*f
, *last
= NULL
;
428 for (f
= frchain_root
; f
; f
= f
->frch_next
)
429 if (f
->frch_seg
== seg
430 && (! last
|| last
->frch_subseg
< f
->frch_subseg
))
433 return last
? last
->frch_last
: NULL
;
436 /* Emit a single byte into the current segment. */
442 FRAG_APPEND_1_CHAR (byte
);
445 /* Emit a statement program opcode into the current segment. */
454 /* Emit a two-byte word into the current segment. */
460 md_number_to_chars (frag_more (2), data
, 2);
463 /* Emit a four byte word into the current segment. */
469 md_number_to_chars (frag_more (4), data
, 4);
472 /* Emit an unsigned "little-endian base 128" number. */
478 output_leb128 (frag_more (sizeof_leb128 (value
, 0)), value
, 0);
481 /* Emit a tuple for .debug_abbrev. */
484 out_abbrev (name
, form
)
491 /* Create a new fake symbol whose value is the current position. */
496 return symbol_new (fake_label_name
, now_seg
, frag_now_fix (), frag_now
);
499 /* Set the value of SYM to the current position in the current segment. */
502 set_symbol_value_now (sym
)
505 S_SET_SEGMENT (sym
, now_seg
);
506 S_SET_VALUE (sym
, frag_now_fix ());
507 symbol_set_frag (sym
, frag_now
);
510 /* Get the size of a fragment. */
521 /* If a fragment is the last in the chain, special measures must be
522 taken to find its size before relaxation, since it may be pending
523 on some subsegment chain. */
524 for (fr
= frchain_root
; fr
; fr
= fr
->frch_next
)
525 if (fr
->frch_last
== frag
)
527 long align_mask
= -1 << get_recorded_alignment (fr
->frch_seg
);
528 return (((char *) obstack_next_free (&fr
->frch_obstack
)
529 - frag
->fr_literal
) + ~align_mask
) & align_mask
;
535 /* Set an absolute address (may result in a relocation entry). */
538 out_set_addr (seg
, frag
, ofs
)
546 sym
= symbol_new (fake_label_name
, seg
, ofs
, frag
);
548 out_opcode (DW_LNS_extended_op
);
549 out_uleb128 (sizeof_address
+ 1);
551 out_opcode (DW_LNE_set_address
);
552 expr
.X_op
= O_symbol
;
553 expr
.X_add_symbol
= sym
;
554 expr
.X_add_number
= 0;
555 emit_expr (&expr
, sizeof_address
);
558 /* Encode a pair of line and address skips as efficiently as possible.
559 Note that the line skip is signed, whereas the address skip is unsigned.
561 The following two routines *must* be kept in sync. This is
562 enforced by making emit_inc_line_addr abort if we do not emit
563 exactly the expected number of bytes. */
566 size_inc_line_addr (line_delta
, addr_delta
)
570 unsigned int tmp
, opcode
;
573 /* Scale the address delta by the minimum instruction length. */
574 #if DWARF2_LINE_MIN_INSN_LENGTH > 1
575 assert (addr_delta
% DWARF2_LINE_MIN_INSN_LENGTH
== 0);
576 addr_delta
/= DWARF2_LINE_MIN_INSN_LENGTH
;
579 /* INT_MAX is a signal that this is actually a DW_LNE_end_sequence.
580 We cannot use special opcodes here, since we want the end_sequence
581 to emit the matrix entry. */
582 if (line_delta
== INT_MAX
)
584 if (addr_delta
== MAX_SPECIAL_ADDR_DELTA
)
587 len
= 1 + sizeof_leb128 (addr_delta
, 0);
591 /* Bias the line delta by the base. */
592 tmp
= line_delta
- DWARF2_LINE_BASE
;
594 /* If the line increment is out of range of a special opcode, we
595 must encode it with DW_LNS_advance_line. */
596 if (tmp
>= DWARF2_LINE_RANGE
)
598 len
= 1 + sizeof_leb128 (line_delta
, 1);
600 tmp
= 0 - DWARF2_LINE_BASE
;
603 /* Bias the opcode by the special opcode base. */
604 tmp
+= DWARF2_LINE_OPCODE_BASE
;
606 /* Avoid overflow when addr_delta is large. */
607 if (addr_delta
< 256 + MAX_SPECIAL_ADDR_DELTA
)
609 /* Try using a special opcode. */
610 opcode
= tmp
+ addr_delta
* DWARF2_LINE_RANGE
;
614 /* Try using DW_LNS_const_add_pc followed by special op. */
615 opcode
= tmp
+ (addr_delta
- MAX_SPECIAL_ADDR_DELTA
) * DWARF2_LINE_RANGE
;
620 /* Otherwise use DW_LNS_advance_pc. */
621 len
+= 1 + sizeof_leb128 (addr_delta
, 0);
623 /* DW_LNS_copy or special opcode. */
630 emit_inc_line_addr (line_delta
, addr_delta
, p
, len
)
636 unsigned int tmp
, opcode
;
640 #if DWARF2_LINE_MIN_INSN_LENGTH > 1
641 /* Scale the address delta by the minimum instruction length. */
642 assert (addr_delta
% DWARF2_LINE_MIN_INSN_LENGTH
== 0);
643 addr_delta
/= DWARF2_LINE_MIN_INSN_LENGTH
;
645 /* INT_MAX is a signal that this is actually a DW_LNE_end_sequence.
646 We cannot use special opcodes here, since we want the end_sequence
647 to emit the matrix entry. */
648 if (line_delta
== INT_MAX
)
650 if (addr_delta
== MAX_SPECIAL_ADDR_DELTA
)
651 *p
++ = DW_LNS_const_add_pc
;
654 *p
++ = DW_LNS_advance_pc
;
655 p
+= output_leb128 (p
, addr_delta
, 0);
658 *p
++ = DW_LNS_extended_op
;
660 *p
++ = DW_LNE_end_sequence
;
664 /* Bias the line delta by the base. */
665 tmp
= line_delta
- DWARF2_LINE_BASE
;
667 /* If the line increment is out of range of a special opcode, we
668 must encode it with DW_LNS_advance_line. */
669 if (tmp
>= DWARF2_LINE_RANGE
)
671 *p
++ = DW_LNS_advance_line
;
672 p
+= output_leb128 (p
, line_delta
, 1);
674 /* Prettier, I think, to use DW_LNS_copy instead of a
675 "line +0, addr +0" special opcode. */
683 tmp
= 0 - DWARF2_LINE_BASE
;
687 /* Bias the opcode by the special opcode base. */
688 tmp
+= DWARF2_LINE_OPCODE_BASE
;
690 /* Avoid overflow when addr_delta is large. */
691 if (addr_delta
< 256 + MAX_SPECIAL_ADDR_DELTA
)
693 /* Try using a special opcode. */
694 opcode
= tmp
+ addr_delta
* DWARF2_LINE_RANGE
;
701 /* Try using DW_LNS_const_add_pc followed by special op. */
702 opcode
= tmp
+ (addr_delta
- MAX_SPECIAL_ADDR_DELTA
) * DWARF2_LINE_RANGE
;
705 *p
++ = DW_LNS_const_add_pc
;
711 /* Otherwise use DW_LNS_advance_pc. */
712 *p
++ = DW_LNS_advance_pc
;
713 p
+= output_leb128 (p
, addr_delta
, 0);
724 /* Handy routine to combine calls to the above two routines. */
727 out_inc_line_addr (line_delta
, addr_delta
)
731 int len
= size_inc_line_addr (line_delta
, addr_delta
);
732 emit_inc_line_addr (line_delta
, addr_delta
, frag_more (len
), len
);
735 /* Generate a variant frag that we can use to relax address/line
736 increments between fragments of the target segment. */
739 relax_inc_line_addr (line_delta
, seg
, to_frag
, to_ofs
, from_frag
, from_ofs
)
742 fragS
*to_frag
, *from_frag
;
743 addressT to_ofs
, from_ofs
;
745 symbolS
*to_sym
, *from_sym
;
749 to_sym
= symbol_new (fake_label_name
, seg
, to_ofs
, to_frag
);
750 from_sym
= symbol_new (fake_label_name
, seg
, from_ofs
, from_frag
);
752 expr
.X_op
= O_subtract
;
753 expr
.X_add_symbol
= to_sym
;
754 expr
.X_op_symbol
= from_sym
;
755 expr
.X_add_number
= 0;
757 /* The maximum size of the frag is the line delta with a maximum
758 sized address delta. */
759 max_chars
= size_inc_line_addr (line_delta
, -DWARF2_LINE_MIN_INSN_LENGTH
);
761 frag_var (rs_dwarf2dbg
, max_chars
, max_chars
, 1,
762 make_expr_symbol (&expr
), line_delta
, NULL
);
765 /* The function estimates the size of a rs_dwarf2dbg variant frag
766 based on the current values of the symbols. It is called before
767 the relaxation loop. We set fr_subtype to the expected length. */
770 dwarf2dbg_estimate_size_before_relax (frag
)
776 addr_delta
= resolve_symbol_value (frag
->fr_symbol
);
777 size
= size_inc_line_addr (frag
->fr_offset
, addr_delta
);
779 frag
->fr_subtype
= size
;
784 /* This function relaxes a rs_dwarf2dbg variant frag based on the
785 current values of the symbols. fr_subtype is the current length
786 of the frag. This returns the change in frag length. */
789 dwarf2dbg_relax_frag (frag
)
792 int old_size
, new_size
;
794 old_size
= frag
->fr_subtype
;
795 new_size
= dwarf2dbg_estimate_size_before_relax (frag
);
797 return new_size
- old_size
;
800 /* This function converts a rs_dwarf2dbg variant frag into a normal
801 fill frag. This is called after all relaxation has been done.
802 fr_subtype will be the desired length of the frag. */
805 dwarf2dbg_convert_frag (frag
)
810 addr_diff
= resolve_symbol_value (frag
->fr_symbol
);
812 /* fr_var carries the max_chars that we created the fragment with.
813 fr_subtype carries the current expected length. We must, of
814 course, have allocated enough memory earlier. */
815 assert (frag
->fr_var
>= (int) frag
->fr_subtype
);
817 emit_inc_line_addr (frag
->fr_offset
, addr_diff
,
818 frag
->fr_literal
+ frag
->fr_fix
, frag
->fr_subtype
);
820 frag
->fr_fix
+= frag
->fr_subtype
;
821 frag
->fr_type
= rs_fill
;
826 /* Generate .debug_line content for the chain of line number entries
827 beginning at E, for segment SEG. */
830 process_entries (seg
, e
)
832 struct line_entry
*e
;
834 unsigned filenum
= 1;
837 unsigned flags
= DWARF2_LINE_DEFAULT_IS_STMT
? DWARF2_FLAG_BEGIN_STMT
: 0;
840 addressT frag_ofs
= 0;
841 addressT last_frag_ofs
;
842 struct line_entry
*next
;
848 if (filenum
!= e
->loc
.filenum
)
850 filenum
= e
->loc
.filenum
;
851 out_opcode (DW_LNS_set_file
);
852 out_uleb128 (filenum
);
856 if (column
!= e
->loc
.column
)
858 column
= e
->loc
.column
;
859 out_opcode (DW_LNS_set_column
);
860 out_uleb128 (column
);
864 if ((e
->loc
.flags
^ flags
) & DWARF2_FLAG_BEGIN_STMT
)
866 flags
= e
->loc
.flags
;
867 out_opcode (DW_LNS_negate_stmt
);
871 if (e
->loc
.flags
& DWARF2_FLAG_BEGIN_BLOCK
)
873 out_opcode (DW_LNS_set_basic_block
);
877 /* Don't try to optimize away redundant entries; gdb wants two
878 entries for a function where the code starts on the same line as
879 the {, and there's no way to identify that case here. Trust gcc
880 to optimize appropriately. */
881 if (1 /* line != e->loc.line || changed */)
883 int line_delta
= e
->loc
.line
- line
;
886 out_set_addr (seg
, e
->frag
, e
->frag_ofs
);
887 out_inc_line_addr (line_delta
, 0);
889 else if (frag
== e
->frag
)
890 out_inc_line_addr (line_delta
, e
->frag_ofs
- frag_ofs
);
892 relax_inc_line_addr (line_delta
, seg
, e
->frag
, e
->frag_ofs
,
896 frag_ofs
= e
->frag_ofs
;
899 else if (frag
== NULL
)
901 out_set_addr (seg
, e
->frag
, e
->frag_ofs
);
903 frag_ofs
= e
->frag_ofs
;
911 /* Emit a DW_LNE_end_sequence for the end of the section. */
912 last_frag
= last_frag_for_seg (seg
);
913 last_frag_ofs
= get_frag_fix (last_frag
);
914 if (frag
== last_frag
)
915 out_inc_line_addr (INT_MAX
, last_frag_ofs
- frag_ofs
);
917 relax_inc_line_addr (INT_MAX
, seg
, last_frag
, last_frag_ofs
,
921 /* Emit the directory and file tables for .debug_line. */
930 /* Terminate directory list. */
933 for (i
= 1; i
< files_in_use
; ++i
)
935 if (files
[i
].filename
== NULL
)
937 as_bad (_("unassigned file number %ld"), (long) i
);
941 size
= strlen (files
[i
].filename
) + 1;
942 cp
= frag_more (size
);
943 memcpy (cp
, files
[i
].filename
, size
);
945 out_uleb128 (files
[i
].dir
); /* directory number */
946 out_uleb128 (0); /* last modification timestamp */
947 out_uleb128 (0); /* filesize */
950 /* Terminate filename list. */
954 /* Emit the collected .debug_line data. */
957 out_debug_line (line_seg
)
962 symbolS
*prologue_end
;
966 subseg_set (line_seg
, 0);
968 line_start
= symbol_new_now ();
969 prologue_end
= symbol_make (fake_label_name
);
970 line_end
= symbol_make (fake_label_name
);
972 /* Total length of the information for this compilation unit. */
973 expr
.X_op
= O_subtract
;
974 expr
.X_add_symbol
= line_end
;
975 expr
.X_op_symbol
= line_start
;
976 expr
.X_add_number
= -4;
977 emit_expr (&expr
, 4);
982 /* Length of the prologue following this length. */
983 expr
.X_op
= O_subtract
;
984 expr
.X_add_symbol
= prologue_end
;
985 expr
.X_op_symbol
= line_start
;
986 expr
.X_add_number
= - (4 + 2 + 4);
987 emit_expr (&expr
, 4);
989 /* Parameters of the state machine. */
990 out_byte (DWARF2_LINE_MIN_INSN_LENGTH
);
991 out_byte (DWARF2_LINE_DEFAULT_IS_STMT
);
992 out_byte (DWARF2_LINE_BASE
);
993 out_byte (DWARF2_LINE_RANGE
);
994 out_byte (DWARF2_LINE_OPCODE_BASE
);
996 /* Standard opcode lengths. */
997 out_byte (0); /* DW_LNS_copy */
998 out_byte (1); /* DW_LNS_advance_pc */
999 out_byte (1); /* DW_LNS_advance_line */
1000 out_byte (1); /* DW_LNS_set_file */
1001 out_byte (1); /* DW_LNS_set_column */
1002 out_byte (0); /* DW_LNS_negate_stmt */
1003 out_byte (0); /* DW_LNS_set_basic_block */
1004 out_byte (0); /* DW_LNS_const_add_pc */
1005 out_byte (1); /* DW_LNS_fixed_advance_pc */
1009 set_symbol_value_now (prologue_end
);
1011 /* For each section, emit a statement program. */
1012 for (s
= all_segs
; s
; s
= s
->next
)
1013 process_entries (s
->seg
, s
->head
->head
);
1015 set_symbol_value_now (line_end
);
1018 /* Emit data for .debug_aranges. */
1021 out_debug_aranges (aranges_seg
, info_seg
)
1025 unsigned int addr_size
= sizeof_address
;
1026 addressT size
, skip
;
1031 size
= 4 + 2 + 4 + 1 + 1;
1033 skip
= 2 * addr_size
- (size
& (2 * addr_size
- 1));
1034 if (skip
== 2 * addr_size
)
1038 for (s
= all_segs
; s
; s
= s
->next
)
1039 size
+= 2 * addr_size
;
1041 size
+= 2 * addr_size
;
1043 subseg_set (aranges_seg
, 0);
1045 /* Length of the compilation unit. */
1046 out_four (size
- 4);
1051 /* Offset to .debug_info. */
1052 expr
.X_op
= O_symbol
;
1053 expr
.X_add_symbol
= section_symbol (info_seg
);
1054 expr
.X_add_number
= 0;
1055 emit_expr (&expr
, 4);
1057 /* Size of an address (offset portion). */
1058 out_byte (addr_size
);
1060 /* Size of a segment descriptor. */
1063 /* Align the header. */
1065 frag_align (ffs (2 * addr_size
) - 1, 0, 0);
1067 for (s
= all_segs
; s
; s
= s
->next
)
1072 frag
= first_frag_for_seg (s
->seg
);
1073 beg
= symbol_new (fake_label_name
, s
->seg
, 0, frag
);
1074 s
->text_start
= beg
;
1076 frag
= last_frag_for_seg (s
->seg
);
1077 end
= symbol_new (fake_label_name
, s
->seg
, get_frag_fix (frag
), frag
);
1080 expr
.X_op
= O_symbol
;
1081 expr
.X_add_symbol
= beg
;
1082 expr
.X_add_number
= 0;
1083 emit_expr (&expr
, addr_size
);
1085 expr
.X_op
= O_subtract
;
1086 expr
.X_add_symbol
= end
;
1087 expr
.X_op_symbol
= beg
;
1088 expr
.X_add_number
= 0;
1089 emit_expr (&expr
, addr_size
);
1092 p
= frag_more (2 * addr_size
);
1093 md_number_to_chars (p
, 0, addr_size
);
1094 md_number_to_chars (p
+ addr_size
, 0, addr_size
);
1097 /* Emit data for .debug_abbrev. Note that this must be kept in
1098 sync with out_debug_info below. */
1101 out_debug_abbrev (abbrev_seg
)
1104 subseg_set (abbrev_seg
, 0);
1107 out_uleb128 (DW_TAG_compile_unit
);
1108 out_byte (DW_CHILDREN_no
);
1109 out_abbrev (DW_AT_stmt_list
, DW_FORM_data4
);
1110 if (all_segs
->next
== NULL
)
1112 out_abbrev (DW_AT_low_pc
, DW_FORM_addr
);
1113 out_abbrev (DW_AT_high_pc
, DW_FORM_addr
);
1115 out_abbrev (DW_AT_comp_dir
, DW_FORM_string
);
1116 out_abbrev (DW_AT_producer
, DW_FORM_string
);
1117 out_abbrev (DW_AT_language
, DW_FORM_data2
);
1120 /* Terminate the abbreviations for this compilation unit. */
1124 /* Emit a description of this compilation unit for .debug_info. */
1127 out_debug_info (info_seg
, abbrev_seg
, line_seg
)
1135 symbolS
*info_start
;
1140 subseg_set (info_seg
, 0);
1142 info_start
= symbol_new_now ();
1143 info_end
= symbol_make (fake_label_name
);
1145 /* Compilation Unit length. */
1146 expr
.X_op
= O_subtract
;
1147 expr
.X_add_symbol
= info_end
;
1148 expr
.X_op_symbol
= info_start
;
1149 expr
.X_add_number
= -4;
1150 emit_expr (&expr
, 4);
1152 /* DWARF version. */
1155 /* .debug_abbrev offset */
1156 expr
.X_op
= O_symbol
;
1157 expr
.X_add_symbol
= section_symbol (abbrev_seg
);
1158 expr
.X_add_number
= 0;
1159 emit_expr (&expr
, 4);
1161 /* Target address size. */
1162 out_byte (sizeof_address
);
1164 /* DW_TAG_compile_unit DIE abbrev */
1167 /* DW_AT_stmt_list */
1168 expr
.X_op
= O_symbol
;
1169 expr
.X_add_symbol
= section_symbol (line_seg
);
1170 expr
.X_add_number
= 0;
1171 emit_expr (&expr
, 4);
1173 /* These two attributes may only be emitted if all of the code is
1174 contiguous. Multiple sections are not that. */
1175 if (all_segs
->next
== NULL
)
1178 expr
.X_op
= O_symbol
;
1179 expr
.X_add_symbol
= all_segs
->text_start
;
1180 expr
.X_add_number
= 0;
1181 emit_expr (&expr
, sizeof_address
);
1184 expr
.X_op
= O_symbol
;
1185 expr
.X_add_symbol
= all_segs
->text_end
;
1186 expr
.X_add_number
= 0;
1187 emit_expr (&expr
, sizeof_address
);
1190 /* DW_AT_comp_dir */
1191 comp_dir
= getpwd ();
1192 len
= strlen (comp_dir
) + 1;
1193 p
= frag_more (len
);
1194 memcpy (p
, comp_dir
, len
);
1196 /* DW_AT_producer */
1197 sprintf (producer
, "GNU AS %s", VERSION
);
1198 len
= strlen (producer
) + 1;
1199 p
= frag_more (len
);
1200 memcpy (p
, producer
, len
);
1202 /* DW_AT_language. Yes, this is probably not really MIPS, but the
1203 dwarf2 draft has no standard code for assembler. */
1204 out_two (DW_LANG_Mips_Assembler
);
1206 set_symbol_value_now (info_end
);
1215 /* If no debug information was recorded, nothing to do. */
1216 if (all_segs
== NULL
&& files_in_use
<= 1)
1219 /* Calculate the size of an address for the target machine. */
1220 sizeof_address
= bfd_arch_bits_per_address (stdoutput
) / 8;
1222 /* Create and switch to the line number section. */
1223 line_seg
= subseg_new (".debug_line", 0);
1224 bfd_set_section_flags (stdoutput
, line_seg
, SEC_READONLY
);
1226 /* For each subsection, chain the debug entries together. */
1227 for (s
= all_segs
; s
; s
= s
->next
)
1229 struct line_subseg
*ss
= s
->head
;
1230 struct line_entry
**ptail
= ss
->ptail
;
1232 while ((ss
= ss
->next
) != NULL
)
1239 out_debug_line (line_seg
);
1241 /* If this is assembler generated line info, we need .debug_info
1242 and .debug_abbrev sections as well. */
1243 if (all_segs
!= NULL
&& debug_type
== DEBUG_DWARF2
)
1249 info_seg
= subseg_new (".debug_info", 0);
1250 abbrev_seg
= subseg_new (".debug_abbrev", 0);
1251 aranges_seg
= subseg_new (".debug_aranges", 0);
1253 bfd_set_section_flags (stdoutput
, info_seg
, SEC_READONLY
);
1254 bfd_set_section_flags (stdoutput
, abbrev_seg
, SEC_READONLY
);
1255 bfd_set_section_flags (stdoutput
, aranges_seg
, SEC_READONLY
);
1257 record_alignment (aranges_seg
, ffs (2 * sizeof_address
) - 1);
1259 out_debug_aranges (aranges_seg
, info_seg
);
1260 out_debug_abbrev (abbrev_seg
);
1261 out_debug_info (info_seg
, abbrev_seg
, line_seg
);
1272 dwarf2dbg_estimate_size_before_relax (frag
)
1273 fragS
*frag ATTRIBUTE_UNUSED
;
1275 as_fatal (_("dwarf2 is not supported for this object file format"));
1280 dwarf2dbg_relax_frag (frag
)
1281 fragS
*frag ATTRIBUTE_UNUSED
;
1283 as_fatal (_("dwarf2 is not supported for this object file format"));
1288 dwarf2dbg_convert_frag (frag
)
1289 fragS
*frag ATTRIBUTE_UNUSED
;
1291 as_fatal (_("dwarf2 is not supported for this object file format"));
1295 dwarf2_emit_insn (size
)
1296 int size ATTRIBUTE_UNUSED
;
1301 dwarf2_directive_file (dummy
)
1302 int dummy ATTRIBUTE_UNUSED
;
1308 dwarf2_directive_loc (dummy
)
1309 int dummy ATTRIBUTE_UNUSED
;
1311 as_fatal (_("dwarf2 is not supported for this object file format"));
1313 #endif /* BFD_ASSEMBLER */