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;
233 static unsigned int line = -1;
234 static unsigned int filenum = -1;
236 /* Early out for as-yet incomplete location information. */
237 if (loc->filenum == 0 || loc->line == 0)
240 /* Don't emit sequences of line symbols for the same line when the
241 symbols apply to assembler code. It is necessary to emit
242 duplicate line symbols when a compiler asks for them, because GDB
243 uses them to determine the end of the prologue. */
244 if (debug_type == DEBUG_DWARF2
245 && line == loc->line && filenum == loc->filenum)
249 filenum = loc->filenum;
251 e = (struct line_entry *) xmalloc (sizeof (*e));
257 ss = get_line_subseg (now_seg, now_subseg);
259 ss->ptail = &e->next;
264 struct dwarf2_line_info *line;
266 if (debug_type == DEBUG_DWARF2)
269 as_where (&filename, &line->line);
270 line->filenum = get_filenum (filename);
272 line->flags = DWARF2_FLAG_BEGIN_STMT;
278 /* Called for each machine instruction, or relatively atomic group of
279 machine instructions (ie built-in macro). The instruction or group
280 is SIZE bytes in length. If dwarf2 line number generation is called
281 for, emit a line statement appropriately. */
284 dwarf2_emit_insn (size)
287 struct dwarf2_line_info loc;
289 if (debug_type != DEBUG_DWARF2 && ! loc_directive_seen)
291 loc_directive_seen = false;
294 dwarf2_gen_line_info (frag_now_fix () - size, &loc);
297 /* Get a .debug_line file number for FILENAME. */
300 get_filenum (filename)
301 const char *filename;
303 static unsigned int last_used;
307 if (strcmp (filename, files[last_used].filename) == 0)
310 for (i = 1; i < files_in_use; ++i)
311 if (strcmp (filename, files[i].filename) == 0)
314 if (i >= files_allocated)
316 unsigned int old = files_allocated;
318 files_allocated = i + 32;
319 files = (struct file_entry *)
320 xrealloc (files, (i + 32) * sizeof (struct file_entry));
322 memset (files + old, 0, (i + 32 - old) * sizeof (struct file_entry));
325 files[i].filename = xstrdup (filename);
327 files_in_use = i + 1;
333 /* Handle the .file directive. */
336 dwarf2_directive_file (dummy)
337 int dummy ATTRIBUTE_UNUSED;
343 /* Continue to accept a bare string and pass it off. */
345 if (*input_line_pointer == '"')
351 num = get_absolute_expression ();
352 filename = demand_copy_C_string (&filename_len);
353 demand_empty_rest_of_line ();
357 as_bad (_("file number less than one"));
361 if (num < (int) files_in_use && files[num].filename != 0)
363 as_bad (_("file number %ld already allocated"), (long) num);
367 if (num >= (int) files_allocated)
369 unsigned int old = files_allocated;
371 files_allocated = num + 16;
372 files = (struct file_entry *)
373 xrealloc (files, (num + 16) * sizeof (struct file_entry));
375 /* Zero the new memory. */
376 memset (files + old, 0, (num + 16 - old) * sizeof (struct file_entry));
379 files[num].filename = filename;
381 files_in_use = num + 1;
385 dwarf2_directive_loc (dummy)
386 int dummy ATTRIBUTE_UNUSED;
388 offsetT filenum, line, column;
390 filenum = get_absolute_expression ();
392 line = get_absolute_expression ();
394 column = get_absolute_expression ();
395 demand_empty_rest_of_line ();
399 as_bad (_("file number less than one"));
402 if (filenum >= (int) files_in_use || files[filenum].filename == 0)
404 as_bad (_("unassigned file number %ld"), (long) filenum);
408 current.filenum = filenum;
410 current.column = column;
411 current.flags = DWARF2_FLAG_BEGIN_STMT;
413 loc_directive_seen = true;
417 listing_source_line (line);
422 first_frag_for_seg (seg)
425 frchainS *f, *first = NULL;
427 for (f = frchain_root; f; f = f->frch_next)
428 if (f->frch_seg == seg
429 && (! first || first->frch_subseg > f->frch_subseg))
432 return first ? first->frch_root : NULL;
436 last_frag_for_seg (seg)
439 frchainS *f, *last = NULL;
441 for (f = frchain_root; f; f = f->frch_next)
442 if (f->frch_seg == seg
443 && (! last || last->frch_subseg < f->frch_subseg))
446 return last ? last->frch_last : NULL;
449 /* Emit a single byte into the current segment. */
455 FRAG_APPEND_1_CHAR (byte);
458 /* Emit a statement program opcode into the current segment. */
467 /* Emit a two-byte word into the current segment. */
473 md_number_to_chars (frag_more (2), data, 2);
476 /* Emit a four byte word into the current segment. */
482 md_number_to_chars (frag_more (4), data, 4);
485 /* Emit an unsigned "little-endian base 128" number. */
491 output_leb128 (frag_more (sizeof_leb128 (value, 0)), value, 0);
494 /* Emit a tuple for .debug_abbrev. */
497 out_abbrev (name, form)
504 /* Create a new fake symbol whose value is the current position. */
509 return symbol_new (fake_label_name, now_seg, frag_now_fix (), frag_now);
512 /* Set the value of SYM to the current position in the current segment. */
515 set_symbol_value_now (sym)
518 S_SET_SEGMENT (sym, now_seg);
519 S_SET_VALUE (sym, frag_now_fix ());
520 symbol_set_frag (sym, frag_now);
523 /* Get the size of a fragment. */
534 /* If a fragment is the last in the chain, special measures must be
535 taken to find its size before relaxation, since it may be pending
536 on some subsegment chain. */
537 for (fr = frchain_root; fr; fr = fr->frch_next)
538 if (fr->frch_last == frag)
540 long align_mask = -1 << get_recorded_alignment (fr->frch_seg);
541 return (((char *) obstack_next_free (&fr->frch_obstack)
542 - frag->fr_literal) + ~align_mask) & align_mask;
548 /* Set an absolute address (may result in a relocation entry). */
551 out_set_addr (seg, frag, ofs)
559 sym = symbol_new (fake_label_name, seg, ofs, frag);
561 out_opcode (DW_LNS_extended_op);
562 out_uleb128 (sizeof_address + 1);
564 out_opcode (DW_LNE_set_address);
565 expr.X_op = O_symbol;
566 expr.X_add_symbol = sym;
567 expr.X_add_number = 0;
568 emit_expr (&expr, sizeof_address);
571 /* Encode a pair of line and address skips as efficiently as possible.
572 Note that the line skip is signed, whereas the address skip is unsigned.
574 The following two routines *must* be kept in sync. This is
575 enforced by making emit_inc_line_addr abort if we do not emit
576 exactly the expected number of bytes. */
579 size_inc_line_addr (line_delta, addr_delta)
583 unsigned int tmp, opcode;
586 /* Scale the address delta by the minimum instruction length. */
587 #if DWARF2_LINE_MIN_INSN_LENGTH > 1
588 assert (addr_delta % DWARF2_LINE_MIN_INSN_LENGTH == 0);
589 addr_delta /= DWARF2_LINE_MIN_INSN_LENGTH;
592 /* INT_MAX is a signal that this is actually a DW_LNE_end_sequence.
593 We cannot use special opcodes here, since we want the end_sequence
594 to emit the matrix entry. */
595 if (line_delta == INT_MAX)
597 if (addr_delta == MAX_SPECIAL_ADDR_DELTA)
600 len = 1 + sizeof_leb128 (addr_delta, 0);
604 /* Bias the line delta by the base. */
605 tmp = line_delta - DWARF2_LINE_BASE;
607 /* If the line increment is out of range of a special opcode, we
608 must encode it with DW_LNS_advance_line. */
609 if (tmp >= DWARF2_LINE_RANGE)
611 len = 1 + sizeof_leb128 (line_delta, 1);
613 tmp = 0 - DWARF2_LINE_BASE;
616 /* Bias the opcode by the special opcode base. */
617 tmp += DWARF2_LINE_OPCODE_BASE;
619 /* Avoid overflow when addr_delta is large. */
620 if (addr_delta < 256 + MAX_SPECIAL_ADDR_DELTA)
622 /* Try using a special opcode. */
623 opcode = tmp + addr_delta * DWARF2_LINE_RANGE;
627 /* Try using DW_LNS_const_add_pc followed by special op. */
628 opcode = tmp + (addr_delta - MAX_SPECIAL_ADDR_DELTA) * DWARF2_LINE_RANGE;
633 /* Otherwise use DW_LNS_advance_pc. */
634 len += 1 + sizeof_leb128 (addr_delta, 0);
636 /* DW_LNS_copy or special opcode. */
643 emit_inc_line_addr (line_delta, addr_delta, p, len)
649 unsigned int tmp, opcode;
653 #if DWARF2_LINE_MIN_INSN_LENGTH > 1
654 /* Scale the address delta by the minimum instruction length. */
655 assert (addr_delta % DWARF2_LINE_MIN_INSN_LENGTH == 0);
656 addr_delta /= DWARF2_LINE_MIN_INSN_LENGTH;
658 /* INT_MAX is a signal that this is actually a DW_LNE_end_sequence.
659 We cannot use special opcodes here, since we want the end_sequence
660 to emit the matrix entry. */
661 if (line_delta == INT_MAX)
663 if (addr_delta == MAX_SPECIAL_ADDR_DELTA)
664 *p++ = DW_LNS_const_add_pc;
667 *p++ = DW_LNS_advance_pc;
668 p += output_leb128 (p, addr_delta, 0);
671 *p++ = DW_LNS_extended_op;
673 *p++ = DW_LNE_end_sequence;
677 /* Bias the line delta by the base. */
678 tmp = line_delta - DWARF2_LINE_BASE;
680 /* If the line increment is out of range of a special opcode, we
681 must encode it with DW_LNS_advance_line. */
682 if (tmp >= DWARF2_LINE_RANGE)
684 *p++ = DW_LNS_advance_line;
685 p += output_leb128 (p, line_delta, 1);
687 /* Prettier, I think, to use DW_LNS_copy instead of a
688 "line +0, addr +0" special opcode. */
696 tmp = 0 - DWARF2_LINE_BASE;
700 /* Bias the opcode by the special opcode base. */
701 tmp += DWARF2_LINE_OPCODE_BASE;
703 /* Avoid overflow when addr_delta is large. */
704 if (addr_delta < 256 + MAX_SPECIAL_ADDR_DELTA)
706 /* Try using a special opcode. */
707 opcode = tmp + addr_delta * DWARF2_LINE_RANGE;
714 /* Try using DW_LNS_const_add_pc followed by special op. */
715 opcode = tmp + (addr_delta - MAX_SPECIAL_ADDR_DELTA) * DWARF2_LINE_RANGE;
718 *p++ = DW_LNS_const_add_pc;
724 /* Otherwise use DW_LNS_advance_pc. */
725 *p++ = DW_LNS_advance_pc;
726 p += output_leb128 (p, addr_delta, 0);
737 /* Handy routine to combine calls to the above two routines. */
740 out_inc_line_addr (line_delta, addr_delta)
744 int len = size_inc_line_addr (line_delta, addr_delta);
745 emit_inc_line_addr (line_delta, addr_delta, frag_more (len), len);
748 /* Generate a variant frag that we can use to relax address/line
749 increments between fragments of the target segment. */
752 relax_inc_line_addr (line_delta, seg, to_frag, to_ofs, from_frag, from_ofs)
755 fragS *to_frag, *from_frag;
756 addressT to_ofs, from_ofs;
758 symbolS *to_sym, *from_sym;
762 to_sym = symbol_new (fake_label_name, seg, to_ofs, to_frag);
763 from_sym = symbol_new (fake_label_name, seg, from_ofs, from_frag);
765 expr.X_op = O_subtract;
766 expr.X_add_symbol = to_sym;
767 expr.X_op_symbol = from_sym;
768 expr.X_add_number = 0;
770 /* The maximum size of the frag is the line delta with a maximum
771 sized address delta. */
772 max_chars = size_inc_line_addr (line_delta, -DWARF2_LINE_MIN_INSN_LENGTH);
774 frag_var (rs_dwarf2dbg, max_chars, max_chars, 1,
775 make_expr_symbol (&expr), line_delta, NULL);
778 /* The function estimates the size of a rs_dwarf2dbg variant frag
779 based on the current values of the symbols. It is called before
780 the relaxation loop. We set fr_subtype to the expected length. */
783 dwarf2dbg_estimate_size_before_relax (frag)
789 addr_delta = resolve_symbol_value (frag->fr_symbol);
790 size = size_inc_line_addr (frag->fr_offset, addr_delta);
792 frag->fr_subtype = size;
797 /* This function relaxes a rs_dwarf2dbg variant frag based on the
798 current values of the symbols. fr_subtype is the current length
799 of the frag. This returns the change in frag length. */
802 dwarf2dbg_relax_frag (frag)
805 int old_size, new_size;
807 old_size = frag->fr_subtype;
808 new_size = dwarf2dbg_estimate_size_before_relax (frag);
810 return new_size - old_size;
813 /* This function converts a rs_dwarf2dbg variant frag into a normal
814 fill frag. This is called after all relaxation has been done.
815 fr_subtype will be the desired length of the frag. */
818 dwarf2dbg_convert_frag (frag)
823 addr_diff = resolve_symbol_value (frag->fr_symbol);
825 /* fr_var carries the max_chars that we created the fragment with.
826 fr_subtype carries the current expected length. We must, of
827 course, have allocated enough memory earlier. */
828 assert (frag->fr_var >= (int) frag->fr_subtype);
830 emit_inc_line_addr (frag->fr_offset, addr_diff,
831 frag->fr_literal + frag->fr_fix, frag->fr_subtype);
833 frag->fr_fix += frag->fr_subtype;
834 frag->fr_type = rs_fill;
839 /* Generate .debug_line content for the chain of line number entries
840 beginning at E, for segment SEG. */
843 process_entries (seg, e)
845 struct line_entry *e;
847 unsigned filenum = 1;
850 unsigned flags = DWARF2_LINE_DEFAULT_IS_STMT ? DWARF2_FLAG_BEGIN_STMT : 0;
853 addressT frag_ofs = 0;
854 addressT last_frag_ofs;
855 struct line_entry *next;
861 if (filenum != e->loc.filenum)
863 filenum = e->loc.filenum;
864 out_opcode (DW_LNS_set_file);
865 out_uleb128 (filenum);
869 if (column != e->loc.column)
871 column = e->loc.column;
872 out_opcode (DW_LNS_set_column);
873 out_uleb128 (column);
877 if ((e->loc.flags ^ flags) & DWARF2_FLAG_BEGIN_STMT)
879 flags = e->loc.flags;
880 out_opcode (DW_LNS_negate_stmt);
884 if (e->loc.flags & DWARF2_FLAG_BEGIN_BLOCK)
886 out_opcode (DW_LNS_set_basic_block);
890 /* Don't try to optimize away redundant entries; gdb wants two
891 entries for a function where the code starts on the same line as
892 the {, and there's no way to identify that case here. Trust gcc
893 to optimize appropriately. */
894 if (1 /* line != e->loc.line || changed */)
896 int line_delta = e->loc.line - line;
899 out_set_addr (seg, e->frag, e->frag_ofs);
900 out_inc_line_addr (line_delta, 0);
902 else if (frag == e->frag)
903 out_inc_line_addr (line_delta, e->frag_ofs - frag_ofs);
905 relax_inc_line_addr (line_delta, seg, e->frag, e->frag_ofs,
909 frag_ofs = e->frag_ofs;
912 else if (frag == NULL)
914 out_set_addr (seg, e->frag, e->frag_ofs);
916 frag_ofs = e->frag_ofs;
924 /* Emit a DW_LNE_end_sequence for the end of the section. */
925 last_frag = last_frag_for_seg (seg);
926 last_frag_ofs = get_frag_fix (last_frag);
927 if (frag == last_frag)
928 out_inc_line_addr (INT_MAX, last_frag_ofs - frag_ofs);
930 relax_inc_line_addr (INT_MAX, seg, last_frag, last_frag_ofs,
934 /* Emit the directory and file tables for .debug_line. */
943 /* Terminate directory list. */
946 for (i = 1; i < files_in_use; ++i)
948 if (files[i].filename == NULL)
950 as_bad (_("unassigned file number %ld"), (long) i);
954 size = strlen (files[i].filename) + 1;
955 cp = frag_more (size);
956 memcpy (cp, files[i].filename, size);
958 out_uleb128 (files[i].dir); /* directory number */
959 out_uleb128 (0); /* last modification timestamp */
960 out_uleb128 (0); /* filesize */
963 /* Terminate filename list. */
967 /* Emit the collected .debug_line data. */
970 out_debug_line (line_seg)
975 symbolS *prologue_end;
979 subseg_set (line_seg, 0);
981 line_start = symbol_new_now ();
982 prologue_end = symbol_make (fake_label_name);
983 line_end = symbol_make (fake_label_name);
985 /* Total length of the information for this compilation unit. */
986 expr.X_op = O_subtract;
987 expr.X_add_symbol = line_end;
988 expr.X_op_symbol = line_start;
989 expr.X_add_number = -4;
990 emit_expr (&expr, 4);
995 /* Length of the prologue following this length. */
996 expr.X_op = O_subtract;
997 expr.X_add_symbol = prologue_end;
998 expr.X_op_symbol = line_start;
999 expr.X_add_number = - (4 + 2 + 4);
1000 emit_expr (&expr, 4);
1002 /* Parameters of the state machine. */
1003 out_byte (DWARF2_LINE_MIN_INSN_LENGTH);
1004 out_byte (DWARF2_LINE_DEFAULT_IS_STMT);
1005 out_byte (DWARF2_LINE_BASE);
1006 out_byte (DWARF2_LINE_RANGE);
1007 out_byte (DWARF2_LINE_OPCODE_BASE);
1009 /* Standard opcode lengths. */
1010 out_byte (0); /* DW_LNS_copy */
1011 out_byte (1); /* DW_LNS_advance_pc */
1012 out_byte (1); /* DW_LNS_advance_line */
1013 out_byte (1); /* DW_LNS_set_file */
1014 out_byte (1); /* DW_LNS_set_column */
1015 out_byte (0); /* DW_LNS_negate_stmt */
1016 out_byte (0); /* DW_LNS_set_basic_block */
1017 out_byte (0); /* DW_LNS_const_add_pc */
1018 out_byte (1); /* DW_LNS_fixed_advance_pc */
1022 set_symbol_value_now (prologue_end);
1024 /* For each section, emit a statement program. */
1025 for (s = all_segs; s; s = s->next)
1026 process_entries (s->seg, s->head->head);
1028 set_symbol_value_now (line_end);
1031 /* Emit data for .debug_aranges. */
1034 out_debug_aranges (aranges_seg, info_seg)
1038 unsigned int addr_size = sizeof_address;
1039 addressT size, skip;
1044 size = 4 + 2 + 4 + 1 + 1;
1046 skip = 2 * addr_size - (size & (2 * addr_size - 1));
1047 if (skip == 2 * addr_size)
1051 for (s = all_segs; s; s = s->next)
1052 size += 2 * addr_size;
1054 size += 2 * addr_size;
1056 subseg_set (aranges_seg, 0);
1058 /* Length of the compilation unit. */
1059 out_four (size - 4);
1064 /* Offset to .debug_info. */
1065 expr.X_op = O_symbol;
1066 expr.X_add_symbol = section_symbol (info_seg);
1067 expr.X_add_number = 0;
1068 emit_expr (&expr, 4);
1070 /* Size of an address (offset portion). */
1071 out_byte (addr_size);
1073 /* Size of a segment descriptor. */
1076 /* Align the header. */
1078 frag_align (ffs (2 * addr_size) - 1, 0, 0);
1080 for (s = all_segs; s; s = s->next)
1085 frag = first_frag_for_seg (s->seg);
1086 beg = symbol_new (fake_label_name, s->seg, 0, frag);
1087 s->text_start = beg;
1089 frag = last_frag_for_seg (s->seg);
1090 end = symbol_new (fake_label_name, s->seg, get_frag_fix (frag), frag);
1093 expr.X_op = O_symbol;
1094 expr.X_add_symbol = beg;
1095 expr.X_add_number = 0;
1096 emit_expr (&expr, addr_size);
1098 expr.X_op = O_subtract;
1099 expr.X_add_symbol = end;
1100 expr.X_op_symbol = beg;
1101 expr.X_add_number = 0;
1102 emit_expr (&expr, addr_size);
1105 p = frag_more (2 * addr_size);
1106 md_number_to_chars (p, 0, addr_size);
1107 md_number_to_chars (p + addr_size, 0, addr_size);
1110 /* Emit data for .debug_abbrev. Note that this must be kept in
1111 sync with out_debug_info below. */
1114 out_debug_abbrev (abbrev_seg)
1117 subseg_set (abbrev_seg, 0);
1120 out_uleb128 (DW_TAG_compile_unit);
1121 out_byte (DW_CHILDREN_no);
1122 out_abbrev (DW_AT_stmt_list, DW_FORM_data4);
1123 if (all_segs->next == NULL)
1125 out_abbrev (DW_AT_low_pc, DW_FORM_addr);
1126 out_abbrev (DW_AT_high_pc, DW_FORM_addr);
1128 out_abbrev (DW_AT_comp_dir, DW_FORM_string);
1129 out_abbrev (DW_AT_producer, DW_FORM_string);
1130 out_abbrev (DW_AT_language, DW_FORM_data2);
1133 /* Terminate the abbreviations for this compilation unit. */
1137 /* Emit a description of this compilation unit for .debug_info. */
1140 out_debug_info (info_seg, abbrev_seg, line_seg)
1148 symbolS *info_start;
1153 subseg_set (info_seg, 0);
1155 info_start = symbol_new_now ();
1156 info_end = symbol_make (fake_label_name);
1158 /* Compilation Unit length. */
1159 expr.X_op = O_subtract;
1160 expr.X_add_symbol = info_end;
1161 expr.X_op_symbol = info_start;
1162 expr.X_add_number = -4;
1163 emit_expr (&expr, 4);
1165 /* DWARF version. */
1168 /* .debug_abbrev offset */
1169 expr.X_op = O_symbol;
1170 expr.X_add_symbol = section_symbol (abbrev_seg);
1171 expr.X_add_number = 0;
1172 emit_expr (&expr, 4);
1174 /* Target address size. */
1175 out_byte (sizeof_address);
1177 /* DW_TAG_compile_unit DIE abbrev */
1180 /* DW_AT_stmt_list */
1181 expr.X_op = O_symbol;
1182 expr.X_add_symbol = section_symbol (line_seg);
1183 expr.X_add_number = 0;
1184 emit_expr (&expr, 4);
1186 /* These two attributes may only be emitted if all of the code is
1187 contiguous. Multiple sections are not that. */
1188 if (all_segs->next == NULL)
1191 expr.X_op = O_symbol;
1192 expr.X_add_symbol = all_segs->text_start;
1193 expr.X_add_number = 0;
1194 emit_expr (&expr, sizeof_address);
1197 expr.X_op = O_symbol;
1198 expr.X_add_symbol = all_segs->text_end;
1199 expr.X_add_number = 0;
1200 emit_expr (&expr, sizeof_address);
1203 /* DW_AT_comp_dir */
1204 comp_dir = getpwd ();
1205 len = strlen (comp_dir) + 1;
1206 p = frag_more (len);
1207 memcpy (p, comp_dir, len);
1209 /* DW_AT_producer */
1210 sprintf (producer, "GNU AS %s", VERSION);
1211 len = strlen (producer) + 1;
1212 p = frag_more (len);
1213 memcpy (p, producer, len);
1215 /* DW_AT_language. Yes, this is probably not really MIPS, but the
1216 dwarf2 draft has no standard code for assembler. */
1217 out_two (DW_LANG_Mips_Assembler);
1219 set_symbol_value_now (info_end);
1228 /* If no debug information was recorded, nothing to do. */
1229 if (all_segs == NULL && files_in_use <= 1)
1232 /* Calculate the size of an address for the target machine. */
1233 sizeof_address = bfd_arch_bits_per_address (stdoutput) / 8;
1235 /* Create and switch to the line number section. */
1236 line_seg = subseg_new (".debug_line", 0);
1237 bfd_set_section_flags (stdoutput, line_seg, SEC_READONLY);
1239 /* For each subsection, chain the debug entries together. */
1240 for (s = all_segs; s; s = s->next)
1242 struct line_subseg *ss = s->head;
1243 struct line_entry **ptail = ss->ptail;
1245 while ((ss = ss->next) != NULL)
1252 out_debug_line (line_seg);
1254 /* If this is assembler generated line info, we need .debug_info
1255 and .debug_abbrev sections as well. */
1256 if (all_segs != NULL && debug_type == DEBUG_DWARF2)
1262 info_seg = subseg_new (".debug_info", 0);
1263 abbrev_seg = subseg_new (".debug_abbrev", 0);
1264 aranges_seg = subseg_new (".debug_aranges", 0);
1266 bfd_set_section_flags (stdoutput, info_seg, SEC_READONLY);
1267 bfd_set_section_flags (stdoutput, abbrev_seg, SEC_READONLY);
1268 bfd_set_section_flags (stdoutput, aranges_seg, SEC_READONLY);
1270 record_alignment (aranges_seg, ffs (2 * sizeof_address) - 1);
1272 out_debug_aranges (aranges_seg, info_seg);
1273 out_debug_abbrev (abbrev_seg);
1274 out_debug_info (info_seg, abbrev_seg, line_seg);
1285 dwarf2dbg_estimate_size_before_relax (frag)
1286 fragS *frag ATTRIBUTE_UNUSED;
1288 as_fatal (_("dwarf2 is not supported for this object file format"));
1293 dwarf2dbg_relax_frag (frag)
1294 fragS *frag ATTRIBUTE_UNUSED;
1296 as_fatal (_("dwarf2 is not supported for this object file format"));
1301 dwarf2dbg_convert_frag (frag)
1302 fragS *frag ATTRIBUTE_UNUSED;
1304 as_fatal (_("dwarf2 is not supported for this object file format"));
1308 dwarf2_emit_insn (size)
1309 int size ATTRIBUTE_UNUSED;
1314 dwarf2_directive_file (dummy)
1315 int dummy ATTRIBUTE_UNUSED;
1321 dwarf2_directive_loc (dummy)
1322 int dummy ATTRIBUTE_UNUSED;
1324 as_fatal (_("dwarf2 is not supported for this object file format"));
1326 #endif /* BFD_ASSEMBLER */