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
< 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 return ((char *) obstack_next_free (&fr
->frch_obstack
)
534 /* Set an absolute address (may result in a relocation entry). */
537 out_set_addr (seg
, frag
, ofs
)
545 sym
= symbol_new (fake_label_name
, seg
, ofs
, frag
);
547 out_opcode (DW_LNS_extended_op
);
548 out_uleb128 (sizeof_address
+ 1);
550 out_opcode (DW_LNE_set_address
);
551 expr
.X_op
= O_symbol
;
552 expr
.X_add_symbol
= sym
;
553 expr
.X_add_number
= 0;
554 emit_expr (&expr
, sizeof_address
);
557 /* Encode a pair of line and address skips as efficiently as possible.
558 Note that the line skip is signed, whereas the address skip is unsigned.
560 The following two routines *must* be kept in sync. This is
561 enforced by making emit_inc_line_addr abort if we do not emit
562 exactly the expected number of bytes. */
565 size_inc_line_addr (line_delta
, addr_delta
)
569 unsigned int tmp
, opcode
;
572 /* Scale the address delta by the minimum instruction length. */
573 #if DWARF2_LINE_MIN_INSN_LENGTH > 1
574 assert (addr_delta
% DWARF2_LINE_MIN_INSN_LENGTH
== 0);
575 addr_delta
/= DWARF2_LINE_MIN_INSN_LENGTH
;
578 /* INT_MAX is a signal that this is actually a DW_LNE_end_sequence.
579 We cannot use special opcodes here, since we want the end_sequence
580 to emit the matrix entry. */
581 if (line_delta
== INT_MAX
)
583 if (addr_delta
== MAX_SPECIAL_ADDR_DELTA
)
586 len
= 1 + sizeof_leb128 (addr_delta
, 0);
590 /* Bias the line delta by the base. */
591 tmp
= line_delta
- DWARF2_LINE_BASE
;
593 /* If the line increment is out of range of a special opcode, we
594 must encode it with DW_LNS_advance_line. */
595 if (tmp
>= DWARF2_LINE_RANGE
)
597 len
= 1 + sizeof_leb128 (line_delta
, 1);
599 tmp
= 0 - DWARF2_LINE_BASE
;
602 /* Bias the opcode by the special opcode base. */
603 tmp
+= DWARF2_LINE_OPCODE_BASE
;
605 /* Avoid overflow when addr_delta is large. */
606 if (addr_delta
< 256 + MAX_SPECIAL_ADDR_DELTA
)
608 /* Try using a special opcode. */
609 opcode
= tmp
+ addr_delta
* DWARF2_LINE_RANGE
;
613 /* Try using DW_LNS_const_add_pc followed by special op. */
614 opcode
= tmp
+ (addr_delta
- MAX_SPECIAL_ADDR_DELTA
) * DWARF2_LINE_RANGE
;
619 /* Otherwise use DW_LNS_advance_pc. */
620 len
+= 1 + sizeof_leb128 (addr_delta
, 0);
622 /* DW_LNS_copy or special opcode. */
629 emit_inc_line_addr (line_delta
, addr_delta
, p
, len
)
635 unsigned int tmp
, opcode
;
639 #if DWARF2_LINE_MIN_INSN_LENGTH > 1
640 /* Scale the address delta by the minimum instruction length. */
641 assert (addr_delta
% DWARF2_LINE_MIN_INSN_LENGTH
== 0);
642 addr_delta
/= DWARF2_LINE_MIN_INSN_LENGTH
;
644 /* INT_MAX is a signal that this is actually a DW_LNE_end_sequence.
645 We cannot use special opcodes here, since we want the end_sequence
646 to emit the matrix entry. */
647 if (line_delta
== INT_MAX
)
649 if (addr_delta
== MAX_SPECIAL_ADDR_DELTA
)
650 *p
++ = DW_LNS_const_add_pc
;
653 *p
++ = DW_LNS_advance_pc
;
654 p
+= output_leb128 (p
, addr_delta
, 0);
657 *p
++ = DW_LNS_extended_op
;
659 *p
++ = DW_LNE_end_sequence
;
663 /* Bias the line delta by the base. */
664 tmp
= line_delta
- DWARF2_LINE_BASE
;
666 /* If the line increment is out of range of a special opcode, we
667 must encode it with DW_LNS_advance_line. */
668 if (tmp
>= DWARF2_LINE_RANGE
)
670 *p
++ = DW_LNS_advance_line
;
671 p
+= output_leb128 (p
, line_delta
, 1);
673 /* Prettier, I think, to use DW_LNS_copy instead of a
674 "line +0, addr +0" special opcode. */
682 tmp
= 0 - DWARF2_LINE_BASE
;
686 /* Bias the opcode by the special opcode base. */
687 tmp
+= DWARF2_LINE_OPCODE_BASE
;
689 /* Avoid overflow when addr_delta is large. */
690 if (addr_delta
< 256 + MAX_SPECIAL_ADDR_DELTA
)
692 /* Try using a special opcode. */
693 opcode
= tmp
+ addr_delta
* DWARF2_LINE_RANGE
;
700 /* Try using DW_LNS_const_add_pc followed by special op. */
701 opcode
= tmp
+ (addr_delta
- MAX_SPECIAL_ADDR_DELTA
) * DWARF2_LINE_RANGE
;
704 *p
++ = DW_LNS_const_add_pc
;
710 /* Otherwise use DW_LNS_advance_pc. */
711 *p
++ = DW_LNS_advance_pc
;
712 p
+= output_leb128 (p
, addr_delta
, 0);
723 /* Handy routine to combine calls to the above two routines. */
726 out_inc_line_addr (line_delta
, addr_delta
)
730 int len
= size_inc_line_addr (line_delta
, addr_delta
);
731 emit_inc_line_addr (line_delta
, addr_delta
, frag_more (len
), len
);
734 /* Generate a variant frag that we can use to relax address/line
735 increments between fragments of the target segment. */
738 relax_inc_line_addr (line_delta
, seg
, to_frag
, to_ofs
, from_frag
, from_ofs
)
741 fragS
*to_frag
, *from_frag
;
742 addressT to_ofs
, from_ofs
;
744 symbolS
*to_sym
, *from_sym
;
748 to_sym
= symbol_new (fake_label_name
, seg
, to_ofs
, to_frag
);
749 from_sym
= symbol_new (fake_label_name
, seg
, from_ofs
, from_frag
);
751 expr
.X_op
= O_subtract
;
752 expr
.X_add_symbol
= to_sym
;
753 expr
.X_op_symbol
= from_sym
;
754 expr
.X_add_number
= 0;
756 /* The maximum size of the frag is the line delta with a maximum
757 sized address delta. */
758 max_chars
= size_inc_line_addr (line_delta
, -DWARF2_LINE_MIN_INSN_LENGTH
);
760 frag_var (rs_dwarf2dbg
, max_chars
, max_chars
, 1,
761 make_expr_symbol (&expr
), line_delta
, NULL
);
764 /* The function estimates the size of a rs_dwarf2dbg variant frag
765 based on the current values of the symbols. It is called before
766 the relaxation loop. We set fr_subtype to the expected length. */
769 dwarf2dbg_estimate_size_before_relax (frag
)
775 addr_delta
= resolve_symbol_value (frag
->fr_symbol
, 0);
776 size
= size_inc_line_addr (frag
->fr_offset
, addr_delta
);
778 frag
->fr_subtype
= size
;
783 /* This function relaxes a rs_dwarf2dbg variant frag based on the
784 current values of the symbols. fr_subtype is the current length
785 of the frag. This returns the change in frag length. */
788 dwarf2dbg_relax_frag (frag
)
791 int old_size
, new_size
;
793 old_size
= frag
->fr_subtype
;
794 new_size
= dwarf2dbg_estimate_size_before_relax (frag
);
796 return new_size
- old_size
;
799 /* This function converts a rs_dwarf2dbg variant frag into a normal
800 fill frag. This is called after all relaxation has been done.
801 fr_subtype will be the desired length of the frag. */
804 dwarf2dbg_convert_frag (frag
)
809 addr_diff
= resolve_symbol_value (frag
->fr_symbol
, 1);
811 /* fr_var carries the max_chars that we created the fragment with.
812 fr_subtype carries the current expected length. We must, of
813 course, have allocated enough memory earlier. */
814 assert (frag
->fr_var
>= (int) frag
->fr_subtype
);
816 emit_inc_line_addr (frag
->fr_offset
, addr_diff
,
817 frag
->fr_literal
+ frag
->fr_fix
, frag
->fr_subtype
);
819 frag
->fr_fix
+= frag
->fr_subtype
;
820 frag
->fr_type
= rs_fill
;
825 /* Generate .debug_line content for the chain of line number entries
826 beginning at E, for segment SEG. */
829 process_entries (seg
, e
)
831 struct line_entry
*e
;
833 unsigned filenum
= 1;
836 unsigned flags
= DWARF2_LINE_DEFAULT_IS_STMT
? DWARF2_FLAG_BEGIN_STMT
: 0;
839 addressT frag_ofs
= 0;
840 addressT last_frag_ofs
;
841 struct line_entry
*next
;
847 if (filenum
!= e
->loc
.filenum
)
849 filenum
= e
->loc
.filenum
;
850 out_opcode (DW_LNS_set_file
);
851 out_uleb128 (filenum
);
855 if (column
!= e
->loc
.column
)
857 column
= e
->loc
.column
;
858 out_opcode (DW_LNS_set_column
);
859 out_uleb128 (column
);
863 if ((e
->loc
.flags
^ flags
) & DWARF2_FLAG_BEGIN_STMT
)
865 flags
= e
->loc
.flags
;
866 out_opcode (DW_LNS_negate_stmt
);
870 if (e
->loc
.flags
& DWARF2_FLAG_BEGIN_BLOCK
)
872 out_opcode (DW_LNS_set_basic_block
);
876 if (line
!= e
->loc
.line
|| changed
)
878 int line_delta
= e
->loc
.line
- line
;
881 out_set_addr (seg
, e
->frag
, e
->frag_ofs
);
882 out_inc_line_addr (line_delta
, 0);
884 else if (frag
== e
->frag
)
885 out_inc_line_addr (line_delta
, e
->frag_ofs
- frag_ofs
);
887 relax_inc_line_addr (line_delta
, seg
, e
->frag
, e
->frag_ofs
,
891 frag_ofs
= e
->frag_ofs
;
894 else if (frag
== NULL
)
896 out_set_addr (seg
, e
->frag
, e
->frag_ofs
);
898 frag_ofs
= e
->frag_ofs
;
906 /* Emit a DW_LNE_end_sequence for the end of the section. */
907 last_frag
= last_frag_for_seg (seg
);
908 last_frag_ofs
= get_frag_fix (last_frag
);
909 if (frag
== last_frag
)
910 out_inc_line_addr (INT_MAX
, last_frag_ofs
- frag_ofs
);
912 relax_inc_line_addr (INT_MAX
, seg
, last_frag
, last_frag_ofs
,
916 /* Emit the directory and file tables for .debug_line. */
925 /* Terminate directory list. */
928 for (i
= 1; i
< files_in_use
; ++i
)
930 if (files
[i
].filename
== NULL
)
932 as_bad (_("Unassigned file number %u"), i
);
936 size
= strlen (files
[i
].filename
) + 1;
937 cp
= frag_more (size
);
938 memcpy (cp
, files
[i
].filename
, size
);
940 out_uleb128 (files
[i
].dir
); /* directory number */
941 out_uleb128 (0); /* last modification timestamp */
942 out_uleb128 (0); /* filesize */
945 /* Terminate filename list. */
949 /* Emit the collected .debug_line data. */
952 out_debug_line (line_seg
)
957 symbolS
*prologue_end
;
961 subseg_set (line_seg
, 0);
963 line_start
= symbol_new_now ();
964 prologue_end
= symbol_make (fake_label_name
);
965 line_end
= symbol_make (fake_label_name
);
967 /* Total length of the information for this compilation unit. */
968 expr
.X_op
= O_subtract
;
969 expr
.X_add_symbol
= line_end
;
970 expr
.X_op_symbol
= line_start
;
971 expr
.X_add_number
= -4;
972 emit_expr (&expr
, 4);
977 /* Length of the prologue following this length. */
978 expr
.X_op
= O_subtract
;
979 expr
.X_add_symbol
= prologue_end
;
980 expr
.X_op_symbol
= line_start
;
981 expr
.X_add_number
= - (4 + 2 + 4);
982 emit_expr (&expr
, 4);
984 /* Parameters of the state machine. */
985 out_byte (DWARF2_LINE_MIN_INSN_LENGTH
);
986 out_byte (DWARF2_LINE_DEFAULT_IS_STMT
);
987 out_byte (DWARF2_LINE_BASE
);
988 out_byte (DWARF2_LINE_RANGE
);
989 out_byte (DWARF2_LINE_OPCODE_BASE
);
991 /* Standard opcode lengths. */
992 out_byte (0); /* DW_LNS_copy */
993 out_byte (1); /* DW_LNS_advance_pc */
994 out_byte (1); /* DW_LNS_advance_line */
995 out_byte (1); /* DW_LNS_set_file */
996 out_byte (1); /* DW_LNS_set_column */
997 out_byte (0); /* DW_LNS_negate_stmt */
998 out_byte (0); /* DW_LNS_set_basic_block */
999 out_byte (0); /* DW_LNS_const_add_pc */
1000 out_byte (1); /* DW_LNS_fixed_advance_pc */
1004 set_symbol_value_now (prologue_end
);
1006 /* For each section, emit a statement program. */
1007 for (s
= all_segs
; s
; s
= s
->next
)
1008 process_entries (s
->seg
, s
->head
->head
);
1010 set_symbol_value_now (line_end
);
1013 /* Emit data for .debug_aranges. */
1016 out_debug_aranges (aranges_seg
, info_seg
)
1020 unsigned int addr_size
= sizeof_address
;
1021 addressT size
, skip
;
1026 size
= 4 + 2 + 4 + 1 + 1;
1028 skip
= 2 * addr_size
- (size
& (2 * addr_size
- 1));
1029 if (skip
== 2 * addr_size
)
1033 for (s
= all_segs
; s
; s
= s
->next
)
1034 size
+= 2 * addr_size
;
1036 size
+= 2 * addr_size
;
1038 subseg_set (aranges_seg
, 0);
1040 /* Length of the compilation unit. */
1041 out_four (size
- 4);
1046 /* Offset to .debug_info. */
1047 expr
.X_op
= O_symbol
;
1048 expr
.X_add_symbol
= section_symbol (info_seg
);
1049 expr
.X_add_number
= 0;
1050 emit_expr (&expr
, 4);
1052 /* Size of an address (offset portion). */
1053 out_byte (addr_size
);
1055 /* Size of a segment descriptor. */
1058 /* Align the header. */
1060 frag_align (ffs (2 * addr_size
) - 1, 0, 0);
1062 for (s
= all_segs
; s
; s
= s
->next
)
1067 frag
= first_frag_for_seg (s
->seg
);
1068 beg
= symbol_new (fake_label_name
, s
->seg
, 0, frag
);
1069 s
->text_start
= beg
;
1071 frag
= last_frag_for_seg (s
->seg
);
1072 end
= symbol_new (fake_label_name
, s
->seg
, get_frag_fix (frag
), frag
);
1075 expr
.X_op
= O_symbol
;
1076 expr
.X_add_symbol
= beg
;
1077 expr
.X_add_number
= 0;
1078 emit_expr (&expr
, addr_size
);
1080 expr
.X_op
= O_subtract
;
1081 expr
.X_add_symbol
= end
;
1082 expr
.X_op_symbol
= beg
;
1083 expr
.X_add_number
= 0;
1084 emit_expr (&expr
, addr_size
);
1087 p
= frag_more (2 * addr_size
);
1088 md_number_to_chars (p
, 0, addr_size
);
1089 md_number_to_chars (p
+ addr_size
, 0, addr_size
);
1092 /* Emit data for .debug_abbrev. Note that this must be kept in
1093 sync with out_debug_info below. */
1096 out_debug_abbrev (abbrev_seg
)
1099 subseg_set (abbrev_seg
, 0);
1102 out_uleb128 (DW_TAG_compile_unit
);
1103 out_byte (DW_CHILDREN_no
);
1104 out_abbrev (DW_AT_stmt_list
, DW_FORM_data4
);
1105 if (all_segs
->next
== NULL
)
1107 out_abbrev (DW_AT_low_pc
, DW_FORM_addr
);
1108 out_abbrev (DW_AT_high_pc
, DW_FORM_addr
);
1110 out_abbrev (DW_AT_comp_dir
, DW_FORM_string
);
1111 out_abbrev (DW_AT_producer
, DW_FORM_string
);
1112 out_abbrev (DW_AT_language
, DW_FORM_data2
);
1115 /* Terminate the abbreviations for this compilation unit. */
1119 /* Emit a description of this compilation unit for .debug_info. */
1122 out_debug_info (info_seg
, abbrev_seg
, line_seg
)
1130 symbolS
*info_start
;
1135 subseg_set (info_seg
, 0);
1137 info_start
= symbol_new_now ();
1138 info_end
= symbol_make (fake_label_name
);
1140 /* Compilation Unit length. */
1141 expr
.X_op
= O_subtract
;
1142 expr
.X_add_symbol
= info_end
;
1143 expr
.X_op_symbol
= info_start
;
1144 expr
.X_add_number
= -4;
1145 emit_expr (&expr
, 4);
1147 /* DWARF version. */
1150 /* .debug_abbrev offset */
1151 expr
.X_op
= O_symbol
;
1152 expr
.X_add_symbol
= section_symbol (abbrev_seg
);
1153 expr
.X_add_number
= 0;
1154 emit_expr (&expr
, 4);
1156 /* Target address size. */
1157 out_byte (sizeof_address
);
1159 /* DW_TAG_compile_unit DIE abbrev */
1162 /* DW_AT_stmt_list */
1163 expr
.X_op
= O_symbol
;
1164 expr
.X_add_symbol
= section_symbol (line_seg
);
1165 expr
.X_add_number
= 0;
1166 emit_expr (&expr
, 4);
1168 /* These two attributes may only be emitted if all of the code is
1169 contiguous. Multiple sections are not that. */
1170 if (all_segs
->next
== NULL
)
1173 expr
.X_op
= O_symbol
;
1174 expr
.X_add_symbol
= all_segs
->text_start
;
1175 expr
.X_add_number
= 0;
1176 emit_expr (&expr
, sizeof_address
);
1179 expr
.X_op
= O_symbol
;
1180 expr
.X_add_symbol
= all_segs
->text_end
;
1181 expr
.X_add_number
= 0;
1182 emit_expr (&expr
, sizeof_address
);
1185 /* DW_AT_comp_dir */
1186 comp_dir
= getpwd ();
1187 len
= strlen (comp_dir
) + 1;
1188 p
= frag_more (len
);
1189 memcpy (p
, comp_dir
, len
);
1191 /* DW_AT_producer */
1192 sprintf (producer
, "GNU AS %s", VERSION
);
1193 len
= strlen (producer
) + 1;
1194 p
= frag_more (len
);
1195 memcpy (p
, producer
, len
);
1197 /* DW_AT_language. Yes, this is probably not really MIPS, but the
1198 dwarf2 draft has no standard code for assembler. */
1199 out_two (DW_LANG_Mips_Assembler
);
1201 set_symbol_value_now (info_end
);
1210 /* If no debug information was recorded, nothing to do. */
1211 if (all_segs
== NULL
)
1214 /* Calculate the size of an address for the target machine. */
1215 sizeof_address
= bfd_arch_bits_per_address (stdoutput
) / 8;
1217 /* Create and switch to the line number section. */
1218 line_seg
= subseg_new (".debug_line", 0);
1219 bfd_set_section_flags (stdoutput
, line_seg
, SEC_READONLY
);
1221 /* For each subsection, chain the debug entries together. */
1222 for (s
= all_segs
; s
; s
= s
->next
)
1224 struct line_subseg
*ss
= s
->head
;
1225 struct line_entry
**ptail
= ss
->ptail
;
1227 while ((ss
= ss
->next
) != NULL
)
1234 out_debug_line (line_seg
);
1236 /* If this is assembler generated line info, we need .debug_info
1237 and .debug_abbrev sections as well. */
1238 if (debug_type
== DEBUG_DWARF2
)
1244 info_seg
= subseg_new (".debug_info", 0);
1245 abbrev_seg
= subseg_new (".debug_abbrev", 0);
1246 aranges_seg
= subseg_new (".debug_aranges", 0);
1248 bfd_set_section_flags (stdoutput
, info_seg
, SEC_READONLY
);
1249 bfd_set_section_flags (stdoutput
, abbrev_seg
, SEC_READONLY
);
1250 bfd_set_section_flags (stdoutput
, aranges_seg
, SEC_READONLY
);
1252 record_alignment (aranges_seg
, ffs (2 * sizeof_address
) - 1);
1254 out_debug_aranges (aranges_seg
, info_seg
);
1255 out_debug_abbrev (abbrev_seg
);
1256 out_debug_info (info_seg
, abbrev_seg
, line_seg
);
1267 dwarf2dbg_estimate_size_before_relax (frag
)
1268 fragS
*frag ATTRIBUTE_UNUSED
;
1270 as_fatal (_("dwarf2 is not supported for this object file format"));
1275 dwarf2dbg_relax_frag (frag
)
1276 fragS
*frag ATTRIBUTE_UNUSED
;
1278 as_fatal (_("dwarf2 is not supported for this object file format"));
1283 dwarf2dbg_convert_frag (frag
)
1284 fragS
*frag ATTRIBUTE_UNUSED
;
1286 as_fatal (_("dwarf2 is not supported for this object file format"));
1290 dwarf2_emit_insn (size
)
1291 int size ATTRIBUTE_UNUSED
;
1296 dwarf2_directive_file (dummy
)
1297 int dummy ATTRIBUTE_UNUSED
;
1303 dwarf2_directive_loc (dummy
)
1304 int dummy ATTRIBUTE_UNUSED
;
1306 as_fatal (_("dwarf2 is not supported for this object file format"));
1308 #endif /* BFD_ASSEMBLER */