1 /* dwarf2dbg.c - DWARF2 debug support
2 Copyright (C) 1999, 2000 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. */
34 #include "dwarf2dbg.h"
37 #include "elf/dwarf2.h"
39 /* Since we can't generate the prolog until the body is complete, we
40 use three different subsegments for .debug_line: one holding the
41 prolog, one for the directory and filename info, and one for the
42 body ("statement program"). */
47 /* First special line opcde - leave room for the standard opcodes.
48 Note: If you want to change this, you'll have to update the
49 "standard_opcode_lengths" table that is emitted below in
51 #define DWARF2_LINE_OPCODE_BASE 10
53 #ifndef DWARF2_LINE_BASE
54 /* Minimum line offset in a special line info. opcode. This value
55 was chosen to give a reasonable range of values. */
56 # define DWARF2_LINE_BASE -5
59 /* Range of line offsets in a special line info. opcode. */
60 #ifndef DWARF2_LINE_RANGE
61 # define DWARF2_LINE_RANGE 14
64 #ifndef DWARF2_LINE_MIN_INSN_LENGTH
65 /* Define the architecture-dependent minimum instruction length (in
66 bytes). This value should be rather too small than too big. */
67 # define DWARF2_LINE_MIN_INSN_LENGTH 1
70 /* Flag that indicates the initial value of the is_stmt_start flag.
71 In the present implementation, we do not mark any lines as
72 the beginning of a source statement, because that information
73 is not made available by the GCC front-end. */
74 #define DWARF2_LINE_DEFAULT_IS_STMT 1
76 /* Given a special op, return the line skip amount. */
77 #define SPECIAL_LINE(op) \
78 (((op) - DWARF2_LINE_OPCODE_BASE)%DWARF2_LINE_RANGE + DWARF2_LINE_BASE)
80 /* Given a special op, return the address skip amount (in units of
81 DWARF2_LINE_MIN_INSN_LENGTH. */
82 #define SPECIAL_ADDR(op) (((op) - DWARF2_LINE_OPCODE_BASE)/DWARF2_LINE_RANGE)
84 /* The maximum address skip amount that can be encoded with a special op. */
85 #define MAX_SPECIAL_ADDR_DELTA SPECIAL_ADDR(255)
90 struct line_entry
*next
;
93 struct dwarf2_line_info loc
;
98 struct line_subseg
*next
;
100 struct line_entry
*head
;
101 struct line_entry
**ptail
;
106 struct line_seg
*next
;
108 struct line_subseg
*head
;
113 /* Collects data for all line table entries during assembly. */
114 static struct line_seg
*all_segs
;
122 /* Table of files used by .debug_line. */
123 static struct file_entry
*files
;
124 static unsigned int files_in_use
;
125 static unsigned int files_allocated
;
127 /* Correlate file numbers as given by the user in .file/.loc directives
128 with the file numbers used in the output debug info. */
129 static unsigned int *user_filenum
;
130 static unsigned int user_filenum_allocated
;
132 /* True when we've seen a .loc directive recently. Used to avoid
133 doing work when there's nothing to do. */
134 static boolean loc_directive_seen
;
136 /* Current location as indicated by the most recent .loc directive. */
137 static struct dwarf2_line_info current
;
139 /* Fake label name. */
140 static char const fake_label_name
[] = ".L0\001";
142 /* The size of an address on the target. */
143 static unsigned int sizeof_address
;
145 static struct line_subseg
*get_line_subseg
PARAMS ((segT
, subsegT
));
146 static unsigned int get_filenum
PARAMS ((const char *));
147 static struct frag
*first_frag_for_seg
PARAMS ((segT
));
148 static struct frag
*last_frag_for_seg
PARAMS ((segT
));
149 static void out_byte
PARAMS ((int));
150 static void out_opcode
PARAMS ((int));
151 static void out_two
PARAMS ((int));
152 static void out_four
PARAMS ((int));
153 static void out_abbrev
PARAMS ((int, int));
154 static void out_uleb128
PARAMS ((addressT
));
155 static symbolS
*symbol_new_now
PARAMS ((void));
156 static void set_symbol_value_now
PARAMS ((symbolS
*));
157 static offsetT get_frag_fix
PARAMS ((fragS
*));
158 static void out_set_addr
PARAMS ((segT
, fragS
*, addressT
));
159 static int size_inc_line_addr
PARAMS ((int, addressT
));
160 static void emit_inc_line_addr
PARAMS ((int, addressT
, char *, int));
161 static void out_inc_line_addr
PARAMS ((int, addressT
));
162 static void relax_inc_line_addr
PARAMS ((int, segT
, fragS
*, addressT
,
164 static void process_entries
PARAMS ((segT
, struct line_entry
*));
165 static void out_file_list
PARAMS ((void));
166 static void out_debug_line
PARAMS ((segT
));
167 static void out_debug_aranges
PARAMS ((segT
, segT
));
168 static void out_debug_abbrev
PARAMS ((segT
));
169 static void out_debug_info
PARAMS ((segT
, segT
, segT
));
171 /* Find or create an entry for SEG+SUBSEG in ALL_SEGS. */
173 static struct line_subseg
*
174 get_line_subseg (seg
, subseg
)
178 static segT last_seg
;
179 static subsegT last_subseg
;
180 static struct line_subseg
*last_line_subseg
;
183 struct line_subseg
**pss
, *ss
;
185 if (seg
== last_seg
&& subseg
== last_subseg
)
186 return last_line_subseg
;
188 for (s
= all_segs
; s
; s
= s
->next
)
192 s
= (struct line_seg
*) xmalloc (sizeof (*s
));
199 for (pss
= &s
->head
; (ss
= *pss
) != NULL
; pss
= &ss
->next
)
201 if (ss
->subseg
== subseg
)
203 if (ss
->subseg
> subseg
)
207 ss
= (struct line_subseg
*) xmalloc (sizeof (*ss
));
211 ss
->ptail
= &ss
->head
;
216 last_subseg
= subseg
;
217 last_line_subseg
= ss
;
222 /* Record an entry for LOC ocurring at OFS within the current fragment. */
225 dwarf2_gen_line_info (ofs
, loc
)
227 struct dwarf2_line_info
*loc
;
229 struct line_subseg
*ss
;
230 struct line_entry
*e
;
232 /* Early out for as-yet incomplete location information. */
233 if (loc
->filenum
== 0 || loc
->line
== 0)
236 e
= (struct line_entry
*) xmalloc (sizeof (*e
));
242 ss
= get_line_subseg (now_seg
, now_subseg
);
244 ss
->ptail
= &e
->next
;
249 struct dwarf2_line_info
*line
;
251 if (debug_type
== DEBUG_DWARF2
)
254 as_where (&filename
, &line
->line
);
255 line
->filenum
= get_filenum (filename
);
257 line
->flags
= DWARF2_FLAG_BEGIN_STMT
;
263 /* Called for each machine instruction, or relatively atomic group of
264 machine instructions (ie built-in macro). The instruction or group
265 is SIZE bytes in length. If dwarf2 line number generation is called
266 for, emit a line statement appropriately. */
269 dwarf2_emit_insn (size
)
272 struct dwarf2_line_info loc
;
274 if (debug_type
!= DEBUG_DWARF2
&& ! loc_directive_seen
)
276 loc_directive_seen
= false;
279 dwarf2_gen_line_info (frag_now_fix () - size
, &loc
);
282 /* Get a .debug_line file number for FILENAME. */
285 get_filenum (filename
)
286 const char *filename
;
288 static unsigned int last_used
;
292 if (strcmp (filename
, files
[last_used
].filename
) == 0)
295 for (i
= 1; i
< files_in_use
; ++i
)
296 if (strcmp (filename
, files
[i
].filename
) == 0)
299 if (i
>= files_allocated
)
301 files_allocated
= i
+ 32;
302 files
= (struct file_entry
*)
303 xrealloc (files
, (i
+ 32) * sizeof(struct file_entry
));
306 files
[i
].filename
= xstrdup(filename
);
308 files_in_use
= i
+ 1;
314 /* Handle the .file directive. */
317 dwarf2_directive_file (dummy
)
318 int dummy ATTRIBUTE_UNUSED
;
321 const char *filename
;
324 /* Continue to accept a bare string and pass it off. */
326 if (*input_line_pointer
== '"')
332 num
= get_absolute_expression ();
333 filename
= demand_copy_C_string (&filename_len
);
334 demand_empty_rest_of_line ();
338 as_bad (_("File number less than zero"));
342 if (num
>= (int) user_filenum_allocated
)
344 unsigned int old
= user_filenum_allocated
;
346 user_filenum_allocated
= num
+ 16;
347 user_filenum
= (unsigned int *)
348 xrealloc (user_filenum
, (num
+ 16) * sizeof (unsigned int));
350 /* Zero the new memory. */
351 memset (user_filenum
+ old
, 0, (num
+ 16 - old
) * sizeof(unsigned int));
354 user_filenum
[num
] = get_filenum (filename
);
358 dwarf2_directive_loc (dummy
)
359 int dummy ATTRIBUTE_UNUSED
;
361 offsetT filenum
, line
, column
;
363 filenum
= get_absolute_expression ();
365 line
= get_absolute_expression ();
367 column
= get_absolute_expression ();
368 demand_empty_rest_of_line ();
372 as_bad (_("File number less than zero"));
375 if (filenum
>= (int) user_filenum_allocated
376 || user_filenum
[filenum
] == 0)
378 as_bad (_("Unassigned file number %ld"), (long) filenum
);
382 current
.filenum
= user_filenum
[filenum
];
384 current
.column
= column
;
385 current
.flags
= DWARF2_FLAG_BEGIN_STMT
;
387 loc_directive_seen
= true;
391 listing_source_line (line
);
397 first_frag_for_seg (seg
)
400 frchainS
*f
, *first
= NULL
;
402 for (f
= frchain_root
; f
; f
= f
->frch_next
)
403 if (f
->frch_seg
== seg
404 && (! first
|| first
->frch_subseg
> f
->frch_subseg
))
407 return first
? first
->frch_root
: NULL
;
411 last_frag_for_seg (seg
)
414 frchainS
*f
, *last
= NULL
;
416 for (f
= frchain_root
; f
; f
= f
->frch_next
)
417 if (f
->frch_seg
== seg
418 && (! last
|| last
->frch_subseg
< f
->frch_subseg
))
421 return last
? last
->frch_last
: NULL
;
424 /* Emit a single byte into the current segment. */
430 FRAG_APPEND_1_CHAR (byte
);
433 /* Emit a statement program opcode into the current segment. */
442 /* Emit a two-byte word into the current segment. */
448 md_number_to_chars (frag_more (2), data
, 2);
451 /* Emit a four byte word into the current segment. */
457 md_number_to_chars (frag_more (4), data
, 4);
460 /* Emit an unsigned "little-endian base 128" number. */
466 output_leb128 (frag_more (sizeof_leb128 (value
, 0)), value
, 0);
469 /* Emit a tuple for .debug_abbrev. */
472 out_abbrev (name
, form
)
479 /* Create a new fake symbol whose value is the current position. */
484 return symbol_new (fake_label_name
, now_seg
, frag_now_fix (), frag_now
);
487 /* Set the value of SYM to the current position in the current segment. */
490 set_symbol_value_now (sym
)
493 S_SET_SEGMENT (sym
, now_seg
);
494 S_SET_VALUE (sym
, frag_now_fix ());
495 symbol_set_frag (sym
, frag_now
);
498 /* Get the size of a fragment. */
509 /* If a fragment is the last in the chain, special measures must be
510 taken to find its size before relaxation, since it may be pending
511 on some subsegment chain. */
512 for (fr
= frchain_root
; fr
; fr
= fr
->frch_next
)
513 if (fr
->frch_last
== frag
)
515 return ((char *) obstack_next_free (&fr
->frch_obstack
)
522 /* Set an absolute address (may result in a relocation entry). */
525 out_set_addr (seg
, frag
, ofs
)
533 sym
= symbol_new (fake_label_name
, seg
, ofs
, frag
);
535 out_opcode (DW_LNS_extended_op
);
536 out_uleb128 (sizeof_address
+ 1);
538 out_opcode (DW_LNE_set_address
);
539 expr
.X_op
= O_symbol
;
540 expr
.X_add_symbol
= sym
;
541 expr
.X_add_number
= 0;
542 emit_expr (&expr
, sizeof_address
);
545 /* Encode a pair of line and address skips as efficiently as possible.
546 Note that the line skip is signed, whereas the address skip is unsigned.
548 The following two routines *must* be kept in sync. This is
549 enforced by making emit_inc_line_addr abort if we do not emit
550 exactly the expected number of bytes. */
553 size_inc_line_addr (line_delta
, addr_delta
)
557 unsigned int tmp
, opcode
;
560 /* Scale the address delta by the minimum instruction length. */
561 #if DWARF2_LINE_MIN_INSN_LENGTH > 1
562 assert (addr_delta
% DWARF2_LINE_MIN_INSN_LENGTH
== 0);
563 addr_delta
/= DWARF2_LINE_MIN_INSN_LENGTH
;
566 /* INT_MAX is a signal that this is actually a DW_LNE_end_sequence.
567 We cannot use special opcodes here, since we want the end_sequence
568 to emit the matrix entry. */
569 if (line_delta
== INT_MAX
)
571 if (addr_delta
== MAX_SPECIAL_ADDR_DELTA
)
574 len
= 1 + sizeof_leb128 (addr_delta
, 0);
578 /* Bias the line delta by the base. */
579 tmp
= line_delta
- DWARF2_LINE_BASE
;
581 /* If the line increment is out of range of a special opcode, we
582 must encode it with DW_LNS_advance_line. */
583 if (tmp
>= DWARF2_LINE_RANGE
)
585 len
= 1 + sizeof_leb128 (line_delta
, 1);
587 tmp
= 0 - DWARF2_LINE_BASE
;
590 /* Bias the opcode by the special opcode base. */
591 tmp
+= DWARF2_LINE_OPCODE_BASE
;
593 /* Avoid overflow when addr_delta is large. */
594 if (addr_delta
< 256 + MAX_SPECIAL_ADDR_DELTA
)
596 /* Try using a special opcode. */
597 opcode
= tmp
+ addr_delta
* DWARF2_LINE_RANGE
;
601 /* Try using DW_LNS_const_add_pc followed by special op. */
602 opcode
= tmp
+ (addr_delta
- MAX_SPECIAL_ADDR_DELTA
) * DWARF2_LINE_RANGE
;
607 /* Otherwise use DW_LNS_advance_pc. */
608 len
+= 1 + sizeof_leb128 (addr_delta
, 0);
610 /* DW_LNS_copy or special opcode. */
617 emit_inc_line_addr (line_delta
, addr_delta
, p
, len
)
623 unsigned int tmp
, opcode
;
627 #if DWARF2_LINE_MIN_INSN_LENGTH > 1
628 /* Scale the address delta by the minimum instruction length. */
629 assert (addr_delta
% DWARF2_LINE_MIN_INSN_LENGTH
== 0);
630 addr_delta
/= DWARF2_LINE_MIN_INSN_LENGTH
;
632 /* INT_MAX is a signal that this is actually a DW_LNE_end_sequence.
633 We cannot use special opcodes here, since we want the end_sequence
634 to emit the matrix entry. */
635 if (line_delta
== INT_MAX
)
637 if (addr_delta
== MAX_SPECIAL_ADDR_DELTA
)
638 *p
++ = DW_LNS_const_add_pc
;
641 *p
++ = DW_LNS_advance_pc
;
642 p
+= output_leb128 (p
, addr_delta
, 0);
645 *p
++ = DW_LNS_extended_op
;
647 *p
++ = DW_LNE_end_sequence
;
651 /* Bias the line delta by the base. */
652 tmp
= line_delta
- DWARF2_LINE_BASE
;
654 /* If the line increment is out of range of a special opcode, we
655 must encode it with DW_LNS_advance_line. */
656 if (tmp
>= DWARF2_LINE_RANGE
)
658 *p
++ = DW_LNS_advance_line
;
659 p
+= output_leb128 (p
, line_delta
, 1);
661 /* Prettier, I think, to use DW_LNS_copy instead of a
662 "line +0, addr +0" special opcode. */
670 tmp
= 0 - DWARF2_LINE_BASE
;
674 /* Bias the opcode by the special opcode base. */
675 tmp
+= DWARF2_LINE_OPCODE_BASE
;
677 /* Avoid overflow when addr_delta is large. */
678 if (addr_delta
< 256 + MAX_SPECIAL_ADDR_DELTA
)
680 /* Try using a special opcode. */
681 opcode
= tmp
+ addr_delta
* DWARF2_LINE_RANGE
;
688 /* Try using DW_LNS_const_add_pc followed by special op. */
689 opcode
= tmp
+ (addr_delta
- MAX_SPECIAL_ADDR_DELTA
) * DWARF2_LINE_RANGE
;
692 *p
++ = DW_LNS_const_add_pc
;
698 /* Otherwise use DW_LNS_advance_pc. */
699 *p
++ = DW_LNS_advance_pc
;
700 p
+= output_leb128 (p
, addr_delta
, 0);
711 /* Handy routine to combine calls to the above two routines. */
714 out_inc_line_addr (line_delta
, addr_delta
)
718 int len
= size_inc_line_addr (line_delta
, addr_delta
);
719 emit_inc_line_addr (line_delta
, addr_delta
, frag_more (len
), len
);
722 /* Generate a variant frag that we can use to relax address/line
723 increments between fragments of the target segment. */
726 relax_inc_line_addr (line_delta
, seg
, to_frag
, to_ofs
, from_frag
, from_ofs
)
729 fragS
*to_frag
, *from_frag
;
730 addressT to_ofs
, from_ofs
;
732 symbolS
*to_sym
, *from_sym
;
736 to_sym
= symbol_new (fake_label_name
, seg
, to_ofs
, to_frag
);
737 from_sym
= symbol_new (fake_label_name
, seg
, from_ofs
, from_frag
);
739 expr
.X_op
= O_subtract
;
740 expr
.X_add_symbol
= to_sym
;
741 expr
.X_op_symbol
= from_sym
;
742 expr
.X_add_number
= 0;
744 /* The maximum size of the frag is the line delta with a maximum
745 sized address delta. */
746 max_chars
= size_inc_line_addr (line_delta
, -DWARF2_LINE_MIN_INSN_LENGTH
);
748 frag_var (rs_dwarf2dbg
, max_chars
, max_chars
, 1,
749 make_expr_symbol (&expr
), line_delta
, NULL
);
752 /* The function estimates the size of a rs_dwarf2dbg variant frag
753 based on the current values of the symbols. It is called before
754 the relaxation loop. We set fr_subtype to the expected length. */
757 dwarf2dbg_estimate_size_before_relax (frag
)
763 addr_delta
= resolve_symbol_value (frag
->fr_symbol
, 0);
764 size
= size_inc_line_addr (frag
->fr_offset
, addr_delta
);
766 frag
->fr_subtype
= size
;
771 /* This function relaxes a rs_dwarf2dbg variant frag based on the
772 current values of the symbols. fr_subtype is the current length
773 of the frag. This returns the change in frag length. */
776 dwarf2dbg_relax_frag (frag
)
779 int old_size
, new_size
;
781 old_size
= frag
->fr_subtype
;
782 new_size
= dwarf2dbg_estimate_size_before_relax (frag
);
784 return new_size
- old_size
;
787 /* This function converts a rs_dwarf2dbg variant frag into a normal
788 fill frag. This is called after all relaxation has been done.
789 fr_subtype will be the desired length of the frag. */
792 dwarf2dbg_convert_frag (frag
)
797 addr_diff
= resolve_symbol_value (frag
->fr_symbol
, 1);
799 /* fr_var carries the max_chars that we created the fragment with.
800 fr_subtype carries the current expected length. We must, of
801 course, have allocated enough memory earlier. */
802 assert (frag
->fr_var
>= (int) frag
->fr_subtype
);
804 emit_inc_line_addr (frag
->fr_offset
, addr_diff
,
805 frag
->fr_literal
+ frag
->fr_fix
, frag
->fr_subtype
);
807 frag
->fr_fix
+= frag
->fr_subtype
;
808 frag
->fr_type
= rs_fill
;
813 /* Generate .debug_line content for the chain of line number entries
814 beginning at E, for segment SEG. */
817 process_entries (seg
, e
)
819 struct line_entry
*e
;
821 unsigned filenum
= 1;
824 unsigned flags
= DWARF2_LINE_DEFAULT_IS_STMT
? DWARF2_FLAG_BEGIN_STMT
: 0;
827 addressT frag_ofs
= 0;
828 addressT last_frag_ofs
;
829 struct line_entry
*next
;
835 if (filenum
!= e
->loc
.filenum
)
837 filenum
= e
->loc
.filenum
;
838 out_opcode (DW_LNS_set_file
);
839 out_uleb128 (filenum
);
843 if (column
!= e
->loc
.column
)
845 column
= e
->loc
.column
;
846 out_opcode (DW_LNS_set_column
);
847 out_uleb128 (column
);
851 if ((e
->loc
.flags
^ flags
) & DWARF2_FLAG_BEGIN_STMT
)
853 flags
= e
->loc
.flags
;
854 out_opcode (DW_LNS_negate_stmt
);
858 if (e
->loc
.flags
& DWARF2_FLAG_BEGIN_BLOCK
)
860 out_opcode (DW_LNS_set_basic_block
);
864 if (line
!= e
->loc
.line
|| changed
)
866 int line_delta
= e
->loc
.line
- line
;
869 out_set_addr (seg
, e
->frag
, e
->frag_ofs
);
870 out_inc_line_addr (line_delta
, 0);
872 else if (frag
== e
->frag
)
873 out_inc_line_addr (line_delta
, e
->frag_ofs
- frag_ofs
);
875 relax_inc_line_addr (line_delta
, seg
, e
->frag
, e
->frag_ofs
,
879 frag_ofs
= e
->frag_ofs
;
882 else if (frag
== NULL
)
884 out_set_addr (seg
, e
->frag
, e
->frag_ofs
);
886 frag_ofs
= e
->frag_ofs
;
894 /* Emit a DW_LNE_end_sequence for the end of the section. */
895 last_frag
= last_frag_for_seg (seg
);
896 last_frag_ofs
= get_frag_fix (last_frag
);
897 if (frag
== last_frag
)
898 out_inc_line_addr (INT_MAX
, last_frag_ofs
- frag_ofs
);
900 relax_inc_line_addr (INT_MAX
, seg
, last_frag
, last_frag_ofs
,
904 /* Emit the directory and file tables for .debug_line. */
913 /* Terminate directory list. */
916 for (i
= 1; i
< files_in_use
; ++i
)
918 size
= strlen (files
[i
].filename
) + 1;
919 cp
= frag_more (size
);
920 memcpy (cp
, files
[i
].filename
, size
);
922 out_uleb128 (files
[i
].dir
); /* directory number */
923 out_uleb128 (0); /* last modification timestamp */
924 out_uleb128 (0); /* filesize */
927 /* Terminate filename list. */
931 /* Emit the collected .debug_line data. */
934 out_debug_line (line_seg
)
939 symbolS
*prologue_end
;
943 subseg_set (line_seg
, 0);
945 line_start
= symbol_new_now ();
946 prologue_end
= symbol_make (fake_label_name
);
947 line_end
= symbol_make (fake_label_name
);
949 /* Total length of the information for this compilation unit. */
950 expr
.X_op
= O_subtract
;
951 expr
.X_add_symbol
= line_end
;
952 expr
.X_op_symbol
= line_start
;
953 expr
.X_add_number
= -4;
954 emit_expr (&expr
, 4);
959 /* Length of the prologue following this length. */
960 expr
.X_op
= O_subtract
;
961 expr
.X_add_symbol
= prologue_end
;
962 expr
.X_op_symbol
= line_start
;
963 expr
.X_add_number
= - (4 + 2 + 4);
964 emit_expr (&expr
, 4);
966 /* Parameters of the state machine. */
967 out_byte (DWARF2_LINE_MIN_INSN_LENGTH
);
968 out_byte (DWARF2_LINE_DEFAULT_IS_STMT
);
969 out_byte (DWARF2_LINE_BASE
);
970 out_byte (DWARF2_LINE_RANGE
);
971 out_byte (DWARF2_LINE_OPCODE_BASE
);
973 /* Standard opcode lengths. */
974 out_byte (0); /* DW_LNS_copy */
975 out_byte (1); /* DW_LNS_advance_pc */
976 out_byte (1); /* DW_LNS_advance_line */
977 out_byte (1); /* DW_LNS_set_file */
978 out_byte (1); /* DW_LNS_set_column */
979 out_byte (0); /* DW_LNS_negate_stmt */
980 out_byte (0); /* DW_LNS_set_basic_block */
981 out_byte (0); /* DW_LNS_const_add_pc */
982 out_byte (1); /* DW_LNS_fixed_advance_pc */
986 set_symbol_value_now (prologue_end
);
988 /* For each section, emit a statement program. */
989 for (s
= all_segs
; s
; s
= s
->next
)
990 process_entries (s
->seg
, s
->head
->head
);
992 set_symbol_value_now (line_end
);
995 /* Emit data for .debug_aranges. */
998 out_debug_aranges (aranges_seg
, info_seg
)
1002 unsigned int addr_size
= sizeof_address
;
1003 addressT size
, skip
;
1008 size
= 4 + 2 + 4 + 1 + 1;
1010 skip
= 2*addr_size
- (size
& (2*addr_size
- 1));
1011 if (skip
== 2*addr_size
)
1015 for (s
= all_segs
; s
; s
= s
->next
)
1016 size
+= 2*addr_size
;
1018 size
+= 2*addr_size
;
1020 subseg_set (aranges_seg
, 0);
1022 /* Length of the compilation unit. */
1023 out_four (size
- 4);
1028 /* Offset to .debug_info. */
1029 expr
.X_op
= O_symbol
;
1030 expr
.X_add_symbol
= section_symbol (info_seg
);
1031 expr
.X_add_number
= 0;
1032 emit_expr (&expr
, 4);
1034 /* Size of an address (offset portion). */
1035 out_byte (addr_size
);
1037 /* Size of a segment descriptor. */
1040 /* Align the header. */
1042 frag_align (ffs (2*addr_size
) - 1, 0, 0);
1044 for (s
= all_segs
; s
; s
= s
->next
)
1049 frag
= first_frag_for_seg (s
->seg
);
1050 beg
= symbol_new (fake_label_name
, s
->seg
, 0, frag
);
1051 s
->text_start
= beg
;
1053 frag
= last_frag_for_seg (s
->seg
);
1054 end
= symbol_new (fake_label_name
, s
->seg
, get_frag_fix (frag
), frag
);
1057 expr
.X_op
= O_symbol
;
1058 expr
.X_add_symbol
= beg
;
1059 expr
.X_add_number
= 0;
1060 emit_expr (&expr
, addr_size
);
1062 expr
.X_op
= O_subtract
;
1063 expr
.X_add_symbol
= end
;
1064 expr
.X_op_symbol
= beg
;
1065 expr
.X_add_number
= 0;
1066 emit_expr (&expr
, addr_size
);
1069 p
= frag_more (2 * addr_size
);
1070 md_number_to_chars (p
, 0, addr_size
);
1071 md_number_to_chars (p
+ addr_size
, 0, addr_size
);
1074 /* Emit data for .debug_abbrev. Note that this must be kept in
1075 sync with out_debug_info below. */
1078 out_debug_abbrev (abbrev_seg
)
1081 subseg_set (abbrev_seg
, 0);
1084 out_uleb128 (DW_TAG_compile_unit
);
1085 out_byte (DW_CHILDREN_no
);
1086 out_abbrev (DW_AT_stmt_list
, DW_FORM_data4
);
1087 if (all_segs
->next
== NULL
)
1089 out_abbrev (DW_AT_low_pc
, DW_FORM_addr
);
1090 out_abbrev (DW_AT_high_pc
, DW_FORM_addr
);
1092 out_abbrev (DW_AT_comp_dir
, DW_FORM_string
);
1093 out_abbrev (DW_AT_producer
, DW_FORM_string
);
1094 out_abbrev (DW_AT_language
, DW_FORM_data2
);
1098 /* Emit a description of this compilation unit for .debug_info. */
1101 out_debug_info (info_seg
, abbrev_seg
, line_seg
)
1109 symbolS
*info_start
;
1114 subseg_set (info_seg
, 0);
1116 info_start
= symbol_new_now();
1117 info_end
= symbol_make (fake_label_name
);
1119 /* Compilation Unit length. */
1120 expr
.X_op
= O_subtract
;
1121 expr
.X_add_symbol
= info_end
;
1122 expr
.X_op_symbol
= info_start
;
1123 expr
.X_add_number
= -4;
1124 emit_expr (&expr
, 4);
1126 /* DWARF version. */
1129 /* .debug_abbrev offset */
1130 expr
.X_op
= O_symbol
;
1131 expr
.X_add_symbol
= section_symbol (abbrev_seg
);
1132 expr
.X_add_number
= 0;
1133 emit_expr (&expr
, 4);
1135 /* Target address size. */
1136 out_byte (sizeof_address
);
1138 /* DW_TAG_compile_unit DIE abbrev */
1141 /* DW_AT_stmt_list */
1142 expr
.X_op
= O_symbol
;
1143 expr
.X_add_symbol
= section_symbol (line_seg
);
1144 expr
.X_add_number
= 0;
1145 emit_expr (&expr
, 4);
1147 /* These two attributes may only be emitted if all of the code is
1148 contiguous. Multiple sections are not that. */
1149 if (all_segs
->next
== NULL
)
1152 expr
.X_op
= O_symbol
;
1153 expr
.X_add_symbol
= all_segs
->text_start
;
1154 expr
.X_add_number
= 0;
1155 emit_expr (&expr
, sizeof_address
);
1158 expr
.X_op
= O_symbol
;
1159 expr
.X_add_symbol
= all_segs
->text_end
;
1160 expr
.X_add_number
= 0;
1161 emit_expr (&expr
, sizeof_address
);
1164 /* DW_AT_comp_dir */
1165 comp_dir
= getpwd ();
1166 len
= strlen (comp_dir
) + 1;
1167 p
= frag_more (len
);
1168 memcpy (p
, comp_dir
, len
);
1170 /* DW_AT_producer */
1171 sprintf (producer
, "GNU AS %s", VERSION
);
1172 len
= strlen (producer
) + 1;
1173 p
= frag_more (len
);
1174 memcpy (p
, producer
, len
);
1176 /* DW_AT_language. Yes, this is probably not really MIPS, but the
1177 dwarf2 draft has no standard code for assembler. */
1178 out_two (DW_LANG_Mips_Assembler
);
1180 set_symbol_value_now (info_end
);
1189 /* If no debug information was recorded, nothing to do. */
1190 if (all_segs
== NULL
)
1193 /* Calculate the size of an address for the target machine. */
1194 #ifdef BFD_ASSEMBLER
1195 sizeof_address
= bfd_arch_bits_per_address (stdoutput
) / 8;
1201 /* Create and switch to the line number section. */
1202 line_seg
= subseg_new (".debug_line", 0);
1203 #ifdef BFD_ASSEMBLER
1204 bfd_set_section_flags (stdoutput
, line_seg
, SEC_READONLY
);
1207 /* For each subsection, chain the debug entries together. */
1208 for (s
= all_segs
; s
; s
= s
->next
)
1210 struct line_subseg
*ss
= s
->head
;
1211 struct line_entry
**ptail
= ss
->ptail
;
1213 while ((ss
= ss
->next
) != NULL
)
1220 out_debug_line (line_seg
);
1222 /* If this is assembler generated line info, we need .debug_info
1223 and .debug_abbrev sections as well. */
1224 if (debug_type
== DEBUG_DWARF2
)
1230 info_seg
= subseg_new (".debug_info", 0);
1231 abbrev_seg
= subseg_new (".debug_abbrev", 0);
1232 aranges_seg
= subseg_new (".debug_aranges", 0);
1234 #ifdef BFD_ASSEMBLER
1235 bfd_set_section_flags (stdoutput
, info_seg
, SEC_READONLY
);
1236 bfd_set_section_flags (stdoutput
, abbrev_seg
, SEC_READONLY
);
1237 bfd_set_section_flags (stdoutput
, aranges_seg
, SEC_READONLY
);
1240 record_alignment (aranges_seg
, ffs (2*sizeof_address
) - 1);
1242 out_debug_aranges (aranges_seg
, info_seg
);
1243 out_debug_abbrev (abbrev_seg
);
1244 out_debug_info (info_seg
, abbrev_seg
, line_seg
);