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. */
36 #define INT_MAX (int) (((unsigned)(-1)) >> 1)
41 #include "dwarf2dbg.h"
44 #include "elf/dwarf2.h"
46 /* Since we can't generate the prolog until the body is complete, we
47 use three different subsegments for .debug_line: one holding the
48 prolog, one for the directory and filename info, and one for the
49 body ("statement program"). */
54 /* First special line opcde - leave room for the standard opcodes.
55 Note: If you want to change this, you'll have to update the
56 "standard_opcode_lengths" table that is emitted below in
58 #define DWARF2_LINE_OPCODE_BASE 10
60 #ifndef DWARF2_LINE_BASE
61 /* Minimum line offset in a special line info. opcode. This value
62 was chosen to give a reasonable range of values. */
63 # define DWARF2_LINE_BASE -5
66 /* Range of line offsets in a special line info. opcode. */
67 #ifndef DWARF2_LINE_RANGE
68 # define DWARF2_LINE_RANGE 14
71 #ifndef DWARF2_LINE_MIN_INSN_LENGTH
72 /* Define the architecture-dependent minimum instruction length (in
73 bytes). This value should be rather too small than too big. */
74 # define DWARF2_LINE_MIN_INSN_LENGTH 1
77 /* Flag that indicates the initial value of the is_stmt_start flag.
78 In the present implementation, we do not mark any lines as
79 the beginning of a source statement, because that information
80 is not made available by the GCC front-end. */
81 #define DWARF2_LINE_DEFAULT_IS_STMT 1
83 /* Given a special op, return the line skip amount. */
84 #define SPECIAL_LINE(op) \
85 (((op) - DWARF2_LINE_OPCODE_BASE)%DWARF2_LINE_RANGE + DWARF2_LINE_BASE)
87 /* Given a special op, return the address skip amount (in units of
88 DWARF2_LINE_MIN_INSN_LENGTH. */
89 #define SPECIAL_ADDR(op) (((op) - DWARF2_LINE_OPCODE_BASE)/DWARF2_LINE_RANGE)
91 /* The maximum address skip amount that can be encoded with a special op. */
92 #define MAX_SPECIAL_ADDR_DELTA SPECIAL_ADDR(255)
97 struct line_entry
*next
;
100 struct dwarf2_line_info loc
;
105 struct line_subseg
*next
;
107 struct line_entry
*head
;
108 struct line_entry
**ptail
;
113 struct line_seg
*next
;
115 struct line_subseg
*head
;
120 /* Collects data for all line table entries during assembly. */
121 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 /* Correlate file numbers as given by the user in .file/.loc directives
135 with the file numbers used in the output debug info. */
136 static unsigned int *user_filenum
;
137 static unsigned int user_filenum_allocated
;
139 /* True when we've seen a .loc directive recently. Used to avoid
140 doing work when there's nothing to do. */
141 static boolean loc_directive_seen
;
143 /* Current location as indicated by the most recent .loc directive. */
144 static struct dwarf2_line_info current
;
146 /* Fake label name. */
147 static char const fake_label_name
[] = ".L0\001";
149 /* The size of an address on the target. */
150 static unsigned int sizeof_address
;
152 static struct line_subseg
*get_line_subseg
PARAMS ((segT
, subsegT
));
153 static unsigned int get_filenum
PARAMS ((const char *));
154 static struct frag
*first_frag_for_seg
PARAMS ((segT
));
155 static struct frag
*last_frag_for_seg
PARAMS ((segT
));
156 static void out_byte
PARAMS ((int));
157 static void out_opcode
PARAMS ((int));
158 static void out_two
PARAMS ((int));
159 static void out_four
PARAMS ((int));
160 static void out_abbrev
PARAMS ((int, int));
161 static void out_uleb128
PARAMS ((addressT
));
162 static symbolS
*symbol_new_now
PARAMS ((void));
163 static void set_symbol_value_now
PARAMS ((symbolS
*));
164 static offsetT get_frag_fix
PARAMS ((fragS
*));
165 static void out_set_addr
PARAMS ((segT
, fragS
*, addressT
));
166 static int size_inc_line_addr
PARAMS ((int, addressT
));
167 static void emit_inc_line_addr
PARAMS ((int, addressT
, char *, int));
168 static void out_inc_line_addr
PARAMS ((int, addressT
));
169 static void relax_inc_line_addr
PARAMS ((int, segT
, fragS
*, addressT
,
171 static void process_entries
PARAMS ((segT
, struct line_entry
*));
172 static void out_file_list
PARAMS ((void));
173 static void out_debug_line
PARAMS ((segT
));
174 static void out_debug_aranges
PARAMS ((segT
, segT
));
175 static void out_debug_abbrev
PARAMS ((segT
));
176 static void out_debug_info
PARAMS ((segT
, segT
, segT
));
178 /* Find or create an entry for SEG+SUBSEG in ALL_SEGS. */
180 static struct line_subseg
*
181 get_line_subseg (seg
, subseg
)
185 static segT last_seg
;
186 static subsegT last_subseg
;
187 static struct line_subseg
*last_line_subseg
;
190 struct line_subseg
**pss
, *ss
;
192 if (seg
== last_seg
&& subseg
== last_subseg
)
193 return last_line_subseg
;
195 for (s
= all_segs
; s
; s
= s
->next
)
199 s
= (struct line_seg
*) xmalloc (sizeof (*s
));
206 for (pss
= &s
->head
; (ss
= *pss
) != NULL
; pss
= &ss
->next
)
208 if (ss
->subseg
== subseg
)
210 if (ss
->subseg
> subseg
)
214 ss
= (struct line_subseg
*) xmalloc (sizeof (*ss
));
218 ss
->ptail
= &ss
->head
;
223 last_subseg
= subseg
;
224 last_line_subseg
= ss
;
229 /* Record an entry for LOC ocurring at OFS within the current fragment. */
232 dwarf2_gen_line_info (ofs
, loc
)
234 struct dwarf2_line_info
*loc
;
236 struct line_subseg
*ss
;
237 struct line_entry
*e
;
239 /* Early out for as-yet incomplete location information. */
240 if (loc
->filenum
== 0 || loc
->line
== 0)
243 e
= (struct line_entry
*) xmalloc (sizeof (*e
));
249 ss
= get_line_subseg (now_seg
, now_subseg
);
251 ss
->ptail
= &e
->next
;
256 struct dwarf2_line_info
*line
;
258 if (debug_type
== DEBUG_DWARF2
)
261 as_where (&filename
, &line
->line
);
262 line
->filenum
= get_filenum (filename
);
264 line
->flags
= DWARF2_FLAG_BEGIN_STMT
;
270 /* Called for each machine instruction, or relatively atomic group of
271 machine instructions (ie built-in macro). The instruction or group
272 is SIZE bytes in length. If dwarf2 line number generation is called
273 for, emit a line statement appropriately. */
276 dwarf2_emit_insn (size
)
279 struct dwarf2_line_info loc
;
281 if (debug_type
!= DEBUG_DWARF2
&& ! loc_directive_seen
)
283 loc_directive_seen
= false;
286 dwarf2_gen_line_info (frag_now_fix () - size
, &loc
);
289 /* Get a .debug_line file number for FILENAME. */
292 get_filenum (filename
)
293 const char *filename
;
295 static unsigned int last_used
;
299 if (strcmp (filename
, files
[last_used
].filename
) == 0)
302 for (i
= 1; i
< files_in_use
; ++i
)
303 if (strcmp (filename
, files
[i
].filename
) == 0)
306 if (i
>= files_allocated
)
308 files_allocated
= i
+ 32;
309 files
= (struct file_entry
*)
310 xrealloc (files
, (i
+ 32) * sizeof(struct file_entry
));
313 files
[i
].filename
= xstrdup(filename
);
315 files_in_use
= i
+ 1;
321 /* Handle the .file directive. */
324 dwarf2_directive_file (dummy
)
325 int dummy ATTRIBUTE_UNUSED
;
328 const char *filename
;
331 /* Continue to accept a bare string and pass it off. */
333 if (*input_line_pointer
== '"')
339 num
= get_absolute_expression ();
340 filename
= demand_copy_C_string (&filename_len
);
341 demand_empty_rest_of_line ();
345 as_bad (_("File number less than zero"));
349 if (num
>= (int) user_filenum_allocated
)
351 unsigned int old
= user_filenum_allocated
;
353 user_filenum_allocated
= num
+ 16;
354 user_filenum
= (unsigned int *)
355 xrealloc (user_filenum
, (num
+ 16) * sizeof (unsigned int));
357 /* Zero the new memory. */
358 memset (user_filenum
+ old
, 0, (num
+ 16 - old
) * sizeof(unsigned int));
361 user_filenum
[num
] = get_filenum (filename
);
365 dwarf2_directive_loc (dummy
)
366 int dummy ATTRIBUTE_UNUSED
;
368 offsetT filenum
, line
, column
;
370 filenum
= get_absolute_expression ();
372 line
= get_absolute_expression ();
374 column
= get_absolute_expression ();
375 demand_empty_rest_of_line ();
379 as_bad (_("File number less than zero"));
382 if (filenum
>= (int) user_filenum_allocated
383 || user_filenum
[filenum
] == 0)
385 as_bad (_("Unassigned file number %ld"), (long) filenum
);
389 current
.filenum
= user_filenum
[filenum
];
391 current
.column
= column
;
392 current
.flags
= DWARF2_FLAG_BEGIN_STMT
;
394 loc_directive_seen
= true;
398 listing_source_line (line
);
404 first_frag_for_seg (seg
)
407 frchainS
*f
, *first
= NULL
;
409 for (f
= frchain_root
; f
; f
= f
->frch_next
)
410 if (f
->frch_seg
== seg
411 && (! first
|| first
->frch_subseg
> f
->frch_subseg
))
414 return first
? first
->frch_root
: NULL
;
418 last_frag_for_seg (seg
)
421 frchainS
*f
, *last
= NULL
;
423 for (f
= frchain_root
; f
; f
= f
->frch_next
)
424 if (f
->frch_seg
== seg
425 && (! last
|| last
->frch_subseg
< f
->frch_subseg
))
428 return last
? last
->frch_last
: NULL
;
431 /* Emit a single byte into the current segment. */
437 FRAG_APPEND_1_CHAR (byte
);
440 /* Emit a statement program opcode into the current segment. */
449 /* Emit a two-byte word into the current segment. */
455 md_number_to_chars (frag_more (2), data
, 2);
458 /* Emit a four byte word into the current segment. */
464 md_number_to_chars (frag_more (4), data
, 4);
467 /* Emit an unsigned "little-endian base 128" number. */
473 output_leb128 (frag_more (sizeof_leb128 (value
, 0)), value
, 0);
476 /* Emit a tuple for .debug_abbrev. */
479 out_abbrev (name
, form
)
486 /* Create a new fake symbol whose value is the current position. */
491 return symbol_new (fake_label_name
, now_seg
, frag_now_fix (), frag_now
);
494 /* Set the value of SYM to the current position in the current segment. */
497 set_symbol_value_now (sym
)
500 S_SET_SEGMENT (sym
, now_seg
);
501 S_SET_VALUE (sym
, frag_now_fix ());
502 symbol_set_frag (sym
, frag_now
);
505 /* Get the size of a fragment. */
516 /* If a fragment is the last in the chain, special measures must be
517 taken to find its size before relaxation, since it may be pending
518 on some subsegment chain. */
519 for (fr
= frchain_root
; fr
; fr
= fr
->frch_next
)
520 if (fr
->frch_last
== frag
)
522 return ((char *) obstack_next_free (&fr
->frch_obstack
)
529 /* Set an absolute address (may result in a relocation entry). */
532 out_set_addr (seg
, frag
, ofs
)
540 sym
= symbol_new (fake_label_name
, seg
, ofs
, frag
);
542 out_opcode (DW_LNS_extended_op
);
543 out_uleb128 (sizeof_address
+ 1);
545 out_opcode (DW_LNE_set_address
);
546 expr
.X_op
= O_symbol
;
547 expr
.X_add_symbol
= sym
;
548 expr
.X_add_number
= 0;
549 emit_expr (&expr
, sizeof_address
);
552 /* Encode a pair of line and address skips as efficiently as possible.
553 Note that the line skip is signed, whereas the address skip is unsigned.
555 The following two routines *must* be kept in sync. This is
556 enforced by making emit_inc_line_addr abort if we do not emit
557 exactly the expected number of bytes. */
560 size_inc_line_addr (line_delta
, addr_delta
)
564 unsigned int tmp
, opcode
;
567 /* Scale the address delta by the minimum instruction length. */
568 #if DWARF2_LINE_MIN_INSN_LENGTH > 1
569 assert (addr_delta
% DWARF2_LINE_MIN_INSN_LENGTH
== 0);
570 addr_delta
/= DWARF2_LINE_MIN_INSN_LENGTH
;
573 /* INT_MAX is a signal that this is actually a DW_LNE_end_sequence.
574 We cannot use special opcodes here, since we want the end_sequence
575 to emit the matrix entry. */
576 if (line_delta
== INT_MAX
)
578 if (addr_delta
== MAX_SPECIAL_ADDR_DELTA
)
581 len
= 1 + sizeof_leb128 (addr_delta
, 0);
585 /* Bias the line delta by the base. */
586 tmp
= line_delta
- DWARF2_LINE_BASE
;
588 /* If the line increment is out of range of a special opcode, we
589 must encode it with DW_LNS_advance_line. */
590 if (tmp
>= DWARF2_LINE_RANGE
)
592 len
= 1 + sizeof_leb128 (line_delta
, 1);
594 tmp
= 0 - DWARF2_LINE_BASE
;
597 /* Bias the opcode by the special opcode base. */
598 tmp
+= DWARF2_LINE_OPCODE_BASE
;
600 /* Avoid overflow when addr_delta is large. */
601 if (addr_delta
< 256 + MAX_SPECIAL_ADDR_DELTA
)
603 /* Try using a special opcode. */
604 opcode
= tmp
+ addr_delta
* DWARF2_LINE_RANGE
;
608 /* Try using DW_LNS_const_add_pc followed by special op. */
609 opcode
= tmp
+ (addr_delta
- MAX_SPECIAL_ADDR_DELTA
) * DWARF2_LINE_RANGE
;
614 /* Otherwise use DW_LNS_advance_pc. */
615 len
+= 1 + sizeof_leb128 (addr_delta
, 0);
617 /* DW_LNS_copy or special opcode. */
624 emit_inc_line_addr (line_delta
, addr_delta
, p
, len
)
630 unsigned int tmp
, opcode
;
634 #if DWARF2_LINE_MIN_INSN_LENGTH > 1
635 /* Scale the address delta by the minimum instruction length. */
636 assert (addr_delta
% DWARF2_LINE_MIN_INSN_LENGTH
== 0);
637 addr_delta
/= DWARF2_LINE_MIN_INSN_LENGTH
;
639 /* INT_MAX is a signal that this is actually a DW_LNE_end_sequence.
640 We cannot use special opcodes here, since we want the end_sequence
641 to emit the matrix entry. */
642 if (line_delta
== INT_MAX
)
644 if (addr_delta
== MAX_SPECIAL_ADDR_DELTA
)
645 *p
++ = DW_LNS_const_add_pc
;
648 *p
++ = DW_LNS_advance_pc
;
649 p
+= output_leb128 (p
, addr_delta
, 0);
652 *p
++ = DW_LNS_extended_op
;
654 *p
++ = DW_LNE_end_sequence
;
658 /* Bias the line delta by the base. */
659 tmp
= line_delta
- DWARF2_LINE_BASE
;
661 /* If the line increment is out of range of a special opcode, we
662 must encode it with DW_LNS_advance_line. */
663 if (tmp
>= DWARF2_LINE_RANGE
)
665 *p
++ = DW_LNS_advance_line
;
666 p
+= output_leb128 (p
, line_delta
, 1);
668 /* Prettier, I think, to use DW_LNS_copy instead of a
669 "line +0, addr +0" special opcode. */
677 tmp
= 0 - DWARF2_LINE_BASE
;
681 /* Bias the opcode by the special opcode base. */
682 tmp
+= DWARF2_LINE_OPCODE_BASE
;
684 /* Avoid overflow when addr_delta is large. */
685 if (addr_delta
< 256 + MAX_SPECIAL_ADDR_DELTA
)
687 /* Try using a special opcode. */
688 opcode
= tmp
+ addr_delta
* DWARF2_LINE_RANGE
;
695 /* Try using DW_LNS_const_add_pc followed by special op. */
696 opcode
= tmp
+ (addr_delta
- MAX_SPECIAL_ADDR_DELTA
) * DWARF2_LINE_RANGE
;
699 *p
++ = DW_LNS_const_add_pc
;
705 /* Otherwise use DW_LNS_advance_pc. */
706 *p
++ = DW_LNS_advance_pc
;
707 p
+= output_leb128 (p
, addr_delta
, 0);
718 /* Handy routine to combine calls to the above two routines. */
721 out_inc_line_addr (line_delta
, addr_delta
)
725 int len
= size_inc_line_addr (line_delta
, addr_delta
);
726 emit_inc_line_addr (line_delta
, addr_delta
, frag_more (len
), len
);
729 /* Generate a variant frag that we can use to relax address/line
730 increments between fragments of the target segment. */
733 relax_inc_line_addr (line_delta
, seg
, to_frag
, to_ofs
, from_frag
, from_ofs
)
736 fragS
*to_frag
, *from_frag
;
737 addressT to_ofs
, from_ofs
;
739 symbolS
*to_sym
, *from_sym
;
743 to_sym
= symbol_new (fake_label_name
, seg
, to_ofs
, to_frag
);
744 from_sym
= symbol_new (fake_label_name
, seg
, from_ofs
, from_frag
);
746 expr
.X_op
= O_subtract
;
747 expr
.X_add_symbol
= to_sym
;
748 expr
.X_op_symbol
= from_sym
;
749 expr
.X_add_number
= 0;
751 /* The maximum size of the frag is the line delta with a maximum
752 sized address delta. */
753 max_chars
= size_inc_line_addr (line_delta
, -DWARF2_LINE_MIN_INSN_LENGTH
);
755 frag_var (rs_dwarf2dbg
, max_chars
, max_chars
, 1,
756 make_expr_symbol (&expr
), line_delta
, NULL
);
759 /* The function estimates the size of a rs_dwarf2dbg variant frag
760 based on the current values of the symbols. It is called before
761 the relaxation loop. We set fr_subtype to the expected length. */
764 dwarf2dbg_estimate_size_before_relax (frag
)
770 addr_delta
= resolve_symbol_value (frag
->fr_symbol
, 0);
771 size
= size_inc_line_addr (frag
->fr_offset
, addr_delta
);
773 frag
->fr_subtype
= size
;
778 /* This function relaxes a rs_dwarf2dbg variant frag based on the
779 current values of the symbols. fr_subtype is the current length
780 of the frag. This returns the change in frag length. */
783 dwarf2dbg_relax_frag (frag
)
786 int old_size
, new_size
;
788 old_size
= frag
->fr_subtype
;
789 new_size
= dwarf2dbg_estimate_size_before_relax (frag
);
791 return new_size
- old_size
;
794 /* This function converts a rs_dwarf2dbg variant frag into a normal
795 fill frag. This is called after all relaxation has been done.
796 fr_subtype will be the desired length of the frag. */
799 dwarf2dbg_convert_frag (frag
)
804 addr_diff
= resolve_symbol_value (frag
->fr_symbol
, 1);
806 /* fr_var carries the max_chars that we created the fragment with.
807 fr_subtype carries the current expected length. We must, of
808 course, have allocated enough memory earlier. */
809 assert (frag
->fr_var
>= (int) frag
->fr_subtype
);
811 emit_inc_line_addr (frag
->fr_offset
, addr_diff
,
812 frag
->fr_literal
+ frag
->fr_fix
, frag
->fr_subtype
);
814 frag
->fr_fix
+= frag
->fr_subtype
;
815 frag
->fr_type
= rs_fill
;
820 /* Generate .debug_line content for the chain of line number entries
821 beginning at E, for segment SEG. */
824 process_entries (seg
, e
)
826 struct line_entry
*e
;
828 unsigned filenum
= 1;
831 unsigned flags
= DWARF2_LINE_DEFAULT_IS_STMT
? DWARF2_FLAG_BEGIN_STMT
: 0;
834 addressT frag_ofs
= 0;
835 addressT last_frag_ofs
;
836 struct line_entry
*next
;
842 if (filenum
!= e
->loc
.filenum
)
844 filenum
= e
->loc
.filenum
;
845 out_opcode (DW_LNS_set_file
);
846 out_uleb128 (filenum
);
850 if (column
!= e
->loc
.column
)
852 column
= e
->loc
.column
;
853 out_opcode (DW_LNS_set_column
);
854 out_uleb128 (column
);
858 if ((e
->loc
.flags
^ flags
) & DWARF2_FLAG_BEGIN_STMT
)
860 flags
= e
->loc
.flags
;
861 out_opcode (DW_LNS_negate_stmt
);
865 if (e
->loc
.flags
& DWARF2_FLAG_BEGIN_BLOCK
)
867 out_opcode (DW_LNS_set_basic_block
);
871 if (line
!= e
->loc
.line
|| changed
)
873 int line_delta
= e
->loc
.line
- line
;
876 out_set_addr (seg
, e
->frag
, e
->frag_ofs
);
877 out_inc_line_addr (line_delta
, 0);
879 else if (frag
== e
->frag
)
880 out_inc_line_addr (line_delta
, e
->frag_ofs
- frag_ofs
);
882 relax_inc_line_addr (line_delta
, seg
, e
->frag
, e
->frag_ofs
,
886 frag_ofs
= e
->frag_ofs
;
889 else if (frag
== NULL
)
891 out_set_addr (seg
, e
->frag
, e
->frag_ofs
);
893 frag_ofs
= e
->frag_ofs
;
901 /* Emit a DW_LNE_end_sequence for the end of the section. */
902 last_frag
= last_frag_for_seg (seg
);
903 last_frag_ofs
= get_frag_fix (last_frag
);
904 if (frag
== last_frag
)
905 out_inc_line_addr (INT_MAX
, last_frag_ofs
- frag_ofs
);
907 relax_inc_line_addr (INT_MAX
, seg
, last_frag
, last_frag_ofs
,
911 /* Emit the directory and file tables for .debug_line. */
920 /* Terminate directory list. */
923 for (i
= 1; i
< files_in_use
; ++i
)
925 size
= strlen (files
[i
].filename
) + 1;
926 cp
= frag_more (size
);
927 memcpy (cp
, files
[i
].filename
, size
);
929 out_uleb128 (files
[i
].dir
); /* directory number */
930 out_uleb128 (0); /* last modification timestamp */
931 out_uleb128 (0); /* filesize */
934 /* Terminate filename list. */
938 /* Emit the collected .debug_line data. */
941 out_debug_line (line_seg
)
946 symbolS
*prologue_end
;
950 subseg_set (line_seg
, 0);
952 line_start
= symbol_new_now ();
953 prologue_end
= symbol_make (fake_label_name
);
954 line_end
= symbol_make (fake_label_name
);
956 /* Total length of the information for this compilation unit. */
957 expr
.X_op
= O_subtract
;
958 expr
.X_add_symbol
= line_end
;
959 expr
.X_op_symbol
= line_start
;
960 expr
.X_add_number
= -4;
961 emit_expr (&expr
, 4);
966 /* Length of the prologue following this length. */
967 expr
.X_op
= O_subtract
;
968 expr
.X_add_symbol
= prologue_end
;
969 expr
.X_op_symbol
= line_start
;
970 expr
.X_add_number
= - (4 + 2 + 4);
971 emit_expr (&expr
, 4);
973 /* Parameters of the state machine. */
974 out_byte (DWARF2_LINE_MIN_INSN_LENGTH
);
975 out_byte (DWARF2_LINE_DEFAULT_IS_STMT
);
976 out_byte (DWARF2_LINE_BASE
);
977 out_byte (DWARF2_LINE_RANGE
);
978 out_byte (DWARF2_LINE_OPCODE_BASE
);
980 /* Standard opcode lengths. */
981 out_byte (0); /* DW_LNS_copy */
982 out_byte (1); /* DW_LNS_advance_pc */
983 out_byte (1); /* DW_LNS_advance_line */
984 out_byte (1); /* DW_LNS_set_file */
985 out_byte (1); /* DW_LNS_set_column */
986 out_byte (0); /* DW_LNS_negate_stmt */
987 out_byte (0); /* DW_LNS_set_basic_block */
988 out_byte (0); /* DW_LNS_const_add_pc */
989 out_byte (1); /* DW_LNS_fixed_advance_pc */
993 set_symbol_value_now (prologue_end
);
995 /* For each section, emit a statement program. */
996 for (s
= all_segs
; s
; s
= s
->next
)
997 process_entries (s
->seg
, s
->head
->head
);
999 set_symbol_value_now (line_end
);
1002 /* Emit data for .debug_aranges. */
1005 out_debug_aranges (aranges_seg
, info_seg
)
1009 unsigned int addr_size
= sizeof_address
;
1010 addressT size
, skip
;
1015 size
= 4 + 2 + 4 + 1 + 1;
1017 skip
= 2*addr_size
- (size
& (2*addr_size
- 1));
1018 if (skip
== 2*addr_size
)
1022 for (s
= all_segs
; s
; s
= s
->next
)
1023 size
+= 2*addr_size
;
1025 size
+= 2*addr_size
;
1027 subseg_set (aranges_seg
, 0);
1029 /* Length of the compilation unit. */
1030 out_four (size
- 4);
1035 /* Offset to .debug_info. */
1036 expr
.X_op
= O_symbol
;
1037 expr
.X_add_symbol
= section_symbol (info_seg
);
1038 expr
.X_add_number
= 0;
1039 emit_expr (&expr
, 4);
1041 /* Size of an address (offset portion). */
1042 out_byte (addr_size
);
1044 /* Size of a segment descriptor. */
1047 /* Align the header. */
1049 frag_align (ffs (2*addr_size
) - 1, 0, 0);
1051 for (s
= all_segs
; s
; s
= s
->next
)
1056 frag
= first_frag_for_seg (s
->seg
);
1057 beg
= symbol_new (fake_label_name
, s
->seg
, 0, frag
);
1058 s
->text_start
= beg
;
1060 frag
= last_frag_for_seg (s
->seg
);
1061 end
= symbol_new (fake_label_name
, s
->seg
, get_frag_fix (frag
), frag
);
1064 expr
.X_op
= O_symbol
;
1065 expr
.X_add_symbol
= beg
;
1066 expr
.X_add_number
= 0;
1067 emit_expr (&expr
, addr_size
);
1069 expr
.X_op
= O_subtract
;
1070 expr
.X_add_symbol
= end
;
1071 expr
.X_op_symbol
= beg
;
1072 expr
.X_add_number
= 0;
1073 emit_expr (&expr
, addr_size
);
1076 p
= frag_more (2 * addr_size
);
1077 md_number_to_chars (p
, 0, addr_size
);
1078 md_number_to_chars (p
+ addr_size
, 0, addr_size
);
1081 /* Emit data for .debug_abbrev. Note that this must be kept in
1082 sync with out_debug_info below. */
1085 out_debug_abbrev (abbrev_seg
)
1088 subseg_set (abbrev_seg
, 0);
1091 out_uleb128 (DW_TAG_compile_unit
);
1092 out_byte (DW_CHILDREN_no
);
1093 out_abbrev (DW_AT_stmt_list
, DW_FORM_data4
);
1094 if (all_segs
->next
== NULL
)
1096 out_abbrev (DW_AT_low_pc
, DW_FORM_addr
);
1097 out_abbrev (DW_AT_high_pc
, DW_FORM_addr
);
1099 out_abbrev (DW_AT_comp_dir
, DW_FORM_string
);
1100 out_abbrev (DW_AT_producer
, DW_FORM_string
);
1101 out_abbrev (DW_AT_language
, DW_FORM_data2
);
1105 /* Emit a description of this compilation unit for .debug_info. */
1108 out_debug_info (info_seg
, abbrev_seg
, line_seg
)
1116 symbolS
*info_start
;
1121 subseg_set (info_seg
, 0);
1123 info_start
= symbol_new_now();
1124 info_end
= symbol_make (fake_label_name
);
1126 /* Compilation Unit length. */
1127 expr
.X_op
= O_subtract
;
1128 expr
.X_add_symbol
= info_end
;
1129 expr
.X_op_symbol
= info_start
;
1130 expr
.X_add_number
= -4;
1131 emit_expr (&expr
, 4);
1133 /* DWARF version. */
1136 /* .debug_abbrev offset */
1137 expr
.X_op
= O_symbol
;
1138 expr
.X_add_symbol
= section_symbol (abbrev_seg
);
1139 expr
.X_add_number
= 0;
1140 emit_expr (&expr
, 4);
1142 /* Target address size. */
1143 out_byte (sizeof_address
);
1145 /* DW_TAG_compile_unit DIE abbrev */
1148 /* DW_AT_stmt_list */
1149 expr
.X_op
= O_symbol
;
1150 expr
.X_add_symbol
= section_symbol (line_seg
);
1151 expr
.X_add_number
= 0;
1152 emit_expr (&expr
, 4);
1154 /* These two attributes may only be emitted if all of the code is
1155 contiguous. Multiple sections are not that. */
1156 if (all_segs
->next
== NULL
)
1159 expr
.X_op
= O_symbol
;
1160 expr
.X_add_symbol
= all_segs
->text_start
;
1161 expr
.X_add_number
= 0;
1162 emit_expr (&expr
, sizeof_address
);
1165 expr
.X_op
= O_symbol
;
1166 expr
.X_add_symbol
= all_segs
->text_end
;
1167 expr
.X_add_number
= 0;
1168 emit_expr (&expr
, sizeof_address
);
1171 /* DW_AT_comp_dir */
1172 comp_dir
= getpwd ();
1173 len
= strlen (comp_dir
) + 1;
1174 p
= frag_more (len
);
1175 memcpy (p
, comp_dir
, len
);
1177 /* DW_AT_producer */
1178 sprintf (producer
, "GNU AS %s", VERSION
);
1179 len
= strlen (producer
) + 1;
1180 p
= frag_more (len
);
1181 memcpy (p
, producer
, len
);
1183 /* DW_AT_language. Yes, this is probably not really MIPS, but the
1184 dwarf2 draft has no standard code for assembler. */
1185 out_two (DW_LANG_Mips_Assembler
);
1187 set_symbol_value_now (info_end
);
1196 /* If no debug information was recorded, nothing to do. */
1197 if (all_segs
== NULL
)
1200 /* Calculate the size of an address for the target machine. */
1201 #ifdef BFD_ASSEMBLER
1202 sizeof_address
= bfd_arch_bits_per_address (stdoutput
) / 8;
1208 /* Create and switch to the line number section. */
1209 line_seg
= subseg_new (".debug_line", 0);
1210 #ifdef BFD_ASSEMBLER
1211 bfd_set_section_flags (stdoutput
, line_seg
, SEC_READONLY
);
1214 /* For each subsection, chain the debug entries together. */
1215 for (s
= all_segs
; s
; s
= s
->next
)
1217 struct line_subseg
*ss
= s
->head
;
1218 struct line_entry
**ptail
= ss
->ptail
;
1220 while ((ss
= ss
->next
) != NULL
)
1227 out_debug_line (line_seg
);
1229 /* If this is assembler generated line info, we need .debug_info
1230 and .debug_abbrev sections as well. */
1231 if (debug_type
== DEBUG_DWARF2
)
1237 info_seg
= subseg_new (".debug_info", 0);
1238 abbrev_seg
= subseg_new (".debug_abbrev", 0);
1239 aranges_seg
= subseg_new (".debug_aranges", 0);
1241 #ifdef BFD_ASSEMBLER
1242 bfd_set_section_flags (stdoutput
, info_seg
, SEC_READONLY
);
1243 bfd_set_section_flags (stdoutput
, abbrev_seg
, SEC_READONLY
);
1244 bfd_set_section_flags (stdoutput
, aranges_seg
, SEC_READONLY
);
1247 record_alignment (aranges_seg
, ffs (2*sizeof_address
) - 1);
1249 out_debug_aranges (aranges_seg
, info_seg
);
1250 out_debug_abbrev (abbrev_seg
);
1251 out_debug_info (info_seg
, abbrev_seg
, line_seg
);
1262 dwarf2dbg_estimate_size_before_relax (frag
)
1263 fragS
*frag ATTRIBUTE_UNUSED
;
1265 as_fatal (_("dwarf2 is not supported for this object file format"));
1270 dwarf2dbg_relax_frag (frag
)
1271 fragS
*frag ATTRIBUTE_UNUSED
;
1273 as_fatal (_("dwarf2 is not supported for this object file format"));
1278 dwarf2dbg_convert_frag (frag
)
1279 fragS
*frag ATTRIBUTE_UNUSED
;
1281 as_fatal (_("dwarf2 is not supported for this object file format"));
1285 dwarf2_emit_insn (size
)
1286 int size ATTRIBUTE_UNUSED
;
1291 dwarf2_directive_file (dummy
)
1292 int dummy ATTRIBUTE_UNUSED
;
1294 as_fatal (_("dwarf2 is not supported for this object file format"));
1298 dwarf2_directive_loc (dummy
)
1299 int dummy ATTRIBUTE_UNUSED
;
1301 as_fatal (_("dwarf2 is not supported for this object file format"));
1303 #endif /* BFD_ASSEMBLER */