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1ea5c32521
* stabs.c (stabs_generate_asm_lineno): Remember file and line number from one call to the next, and eliminate consecutive duplicates (thereby emitting only one line symbol per source line). * dwarf2dbg.c (dwarf2_gen_line_info): Ditto.
1323 lines
32 KiB
C
1323 lines
32 KiB
C
/* dwarf2dbg.c - DWARF2 debug support
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Copyright 1999, 2000, 2001 Free Software Foundation, Inc.
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Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
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This file is part of GAS, the GNU Assembler.
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GAS is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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GAS is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GAS; see the file COPYING. If not, write to the Free
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Software Foundation, 59 Temple Place - Suite 330, Boston, MA
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02111-1307, USA. */
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/* Logical line numbers can be controlled by the compiler via the
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following two directives:
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.file FILENO "file.c"
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.loc FILENO LINENO [COLUMN]
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FILENO is the filenumber. */
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#include "ansidecl.h"
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#include "as.h"
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#ifdef HAVE_LIMITS_H
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#include <limits.h>
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#else
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#ifdef HAVE_SYS_PARAM_H
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#include <sys/param.h>
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#endif
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#ifndef INT_MAX
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#define INT_MAX (int) (((unsigned) (-1)) >> 1)
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#endif
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#endif
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#ifdef BFD_ASSEMBLER
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#include "dwarf2dbg.h"
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#include "subsegs.h"
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#include "elf/dwarf2.h"
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/* Since we can't generate the prolog until the body is complete, we
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use three different subsegments for .debug_line: one holding the
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prolog, one for the directory and filename info, and one for the
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body ("statement program"). */
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#define DL_PROLOG 0
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#define DL_FILES 1
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#define DL_BODY 2
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/* First special line opcde - leave room for the standard opcodes.
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Note: If you want to change this, you'll have to update the
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"standard_opcode_lengths" table that is emitted below in
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dwarf2_finish(). */
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#define DWARF2_LINE_OPCODE_BASE 10
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#ifndef DWARF2_LINE_BASE
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/* Minimum line offset in a special line info. opcode. This value
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was chosen to give a reasonable range of values. */
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# define DWARF2_LINE_BASE -5
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#endif
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/* Range of line offsets in a special line info. opcode. */
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#ifndef DWARF2_LINE_RANGE
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# define DWARF2_LINE_RANGE 14
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#endif
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#ifndef DWARF2_LINE_MIN_INSN_LENGTH
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/* Define the architecture-dependent minimum instruction length (in
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bytes). This value should be rather too small than too big. */
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# define DWARF2_LINE_MIN_INSN_LENGTH 1
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#endif
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/* Flag that indicates the initial value of the is_stmt_start flag.
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In the present implementation, we do not mark any lines as
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the beginning of a source statement, because that information
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is not made available by the GCC front-end. */
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#define DWARF2_LINE_DEFAULT_IS_STMT 1
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/* Given a special op, return the line skip amount. */
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#define SPECIAL_LINE(op) \
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(((op) - DWARF2_LINE_OPCODE_BASE)%DWARF2_LINE_RANGE + DWARF2_LINE_BASE)
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/* Given a special op, return the address skip amount (in units of
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DWARF2_LINE_MIN_INSN_LENGTH. */
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#define SPECIAL_ADDR(op) (((op) - DWARF2_LINE_OPCODE_BASE)/DWARF2_LINE_RANGE)
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/* The maximum address skip amount that can be encoded with a special op. */
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#define MAX_SPECIAL_ADDR_DELTA SPECIAL_ADDR(255)
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struct line_entry {
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struct line_entry *next;
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fragS *frag;
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addressT frag_ofs;
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struct dwarf2_line_info loc;
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};
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struct line_subseg {
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struct line_subseg *next;
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subsegT subseg;
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struct line_entry *head;
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struct line_entry **ptail;
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};
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struct line_seg {
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struct line_seg *next;
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segT seg;
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struct line_subseg *head;
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symbolS *text_start;
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symbolS *text_end;
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};
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/* Collects data for all line table entries during assembly. */
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static struct line_seg *all_segs;
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struct file_entry {
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char *filename;
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unsigned int dir;
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};
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/* Table of files used by .debug_line. */
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static struct file_entry *files;
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static unsigned int files_in_use;
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static unsigned int files_allocated;
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/* True when we've seen a .loc directive recently. Used to avoid
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doing work when there's nothing to do. */
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static boolean loc_directive_seen;
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/* Current location as indicated by the most recent .loc directive. */
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static struct dwarf2_line_info current;
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/* Fake label name. */
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static char const fake_label_name[] = ".L0\001";
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/* The size of an address on the target. */
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static unsigned int sizeof_address;
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static struct line_subseg *get_line_subseg PARAMS ((segT, subsegT));
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static unsigned int get_filenum PARAMS ((const char *));
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static struct frag *first_frag_for_seg PARAMS ((segT));
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static struct frag *last_frag_for_seg PARAMS ((segT));
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static void out_byte PARAMS ((int));
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static void out_opcode PARAMS ((int));
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static void out_two PARAMS ((int));
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static void out_four PARAMS ((int));
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static void out_abbrev PARAMS ((int, int));
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static void out_uleb128 PARAMS ((addressT));
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static symbolS *symbol_new_now PARAMS ((void));
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static void set_symbol_value_now PARAMS ((symbolS *));
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static offsetT get_frag_fix PARAMS ((fragS *));
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static void out_set_addr PARAMS ((segT, fragS *, addressT));
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static int size_inc_line_addr PARAMS ((int, addressT));
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static void emit_inc_line_addr PARAMS ((int, addressT, char *, int));
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static void out_inc_line_addr PARAMS ((int, addressT));
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static void relax_inc_line_addr PARAMS ((int, segT, fragS *, addressT,
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fragS *, addressT));
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static void process_entries PARAMS ((segT, struct line_entry *));
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static void out_file_list PARAMS ((void));
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static void out_debug_line PARAMS ((segT));
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static void out_debug_aranges PARAMS ((segT, segT));
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static void out_debug_abbrev PARAMS ((segT));
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static void out_debug_info PARAMS ((segT, segT, segT));
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/* Find or create an entry for SEG+SUBSEG in ALL_SEGS. */
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static struct line_subseg *
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get_line_subseg (seg, subseg)
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segT seg;
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subsegT subseg;
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{
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static segT last_seg;
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static subsegT last_subseg;
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static struct line_subseg *last_line_subseg;
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struct line_seg *s;
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struct line_subseg **pss, *ss;
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if (seg == last_seg && subseg == last_subseg)
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return last_line_subseg;
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for (s = all_segs; s; s = s->next)
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if (s->seg == seg)
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goto found_seg;
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s = (struct line_seg *) xmalloc (sizeof (*s));
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s->next = all_segs;
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s->seg = seg;
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s->head = NULL;
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all_segs = s;
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found_seg:
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for (pss = &s->head; (ss = *pss) != NULL ; pss = &ss->next)
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{
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if (ss->subseg == subseg)
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goto found_subseg;
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if (ss->subseg > subseg)
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break;
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}
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ss = (struct line_subseg *) xmalloc (sizeof (*ss));
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ss->next = *pss;
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ss->subseg = subseg;
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ss->head = NULL;
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ss->ptail = &ss->head;
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*pss = ss;
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found_subseg:
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last_seg = seg;
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last_subseg = subseg;
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last_line_subseg = ss;
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return ss;
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}
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/* Record an entry for LOC ocurring at OFS within the current fragment. */
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void
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dwarf2_gen_line_info (ofs, loc)
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addressT ofs;
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struct dwarf2_line_info *loc;
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{
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struct line_subseg *ss;
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struct line_entry *e;
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static unsigned int line = -1;
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static unsigned int filenum = -1;
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/* Early out for as-yet incomplete location information. */
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if (loc->filenum == 0 || loc->line == 0)
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return;
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/* Don't emit sequences of line symbols for the same line. */
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if (line == loc->line && filenum == loc->filenum)
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return;
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line = loc->line;
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filenum = loc->filenum;
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e = (struct line_entry *) xmalloc (sizeof (*e));
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e->next = NULL;
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e->frag = frag_now;
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e->frag_ofs = ofs;
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e->loc = *loc;
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ss = get_line_subseg (now_seg, now_subseg);
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*ss->ptail = e;
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ss->ptail = &e->next;
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}
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void
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dwarf2_where (line)
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struct dwarf2_line_info *line;
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{
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if (debug_type == DEBUG_DWARF2)
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{
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char *filename;
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as_where (&filename, &line->line);
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line->filenum = get_filenum (filename);
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line->column = 0;
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line->flags = DWARF2_FLAG_BEGIN_STMT;
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}
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else
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*line = current;
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}
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/* Called for each machine instruction, or relatively atomic group of
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machine instructions (ie built-in macro). The instruction or group
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is SIZE bytes in length. If dwarf2 line number generation is called
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for, emit a line statement appropriately. */
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void
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dwarf2_emit_insn (size)
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int size;
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{
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struct dwarf2_line_info loc;
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if (debug_type != DEBUG_DWARF2 && ! loc_directive_seen)
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return;
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loc_directive_seen = false;
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dwarf2_where (&loc);
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dwarf2_gen_line_info (frag_now_fix () - size, &loc);
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}
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/* Get a .debug_line file number for FILENAME. */
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static unsigned int
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get_filenum (filename)
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const char *filename;
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{
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static unsigned int last_used;
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unsigned int i;
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if (last_used)
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if (strcmp (filename, files[last_used].filename) == 0)
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return last_used;
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for (i = 1; i < files_in_use; ++i)
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if (strcmp (filename, files[i].filename) == 0)
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return i;
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if (i >= files_allocated)
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{
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unsigned int old = files_allocated;
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files_allocated = i + 32;
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files = (struct file_entry *)
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xrealloc (files, (i + 32) * sizeof (struct file_entry));
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memset (files + old, 0, (i + 32 - old) * sizeof (struct file_entry));
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}
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files[i].filename = xstrdup (filename);
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files[i].dir = 0;
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files_in_use = i + 1;
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last_used = i;
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return i;
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}
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/* Handle the .file directive. */
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void
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dwarf2_directive_file (dummy)
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int dummy ATTRIBUTE_UNUSED;
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{
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offsetT num;
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char *filename;
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int filename_len;
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/* Continue to accept a bare string and pass it off. */
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SKIP_WHITESPACE ();
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if (*input_line_pointer == '"')
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{
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s_app_file (0);
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return;
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}
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num = get_absolute_expression ();
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filename = demand_copy_C_string (&filename_len);
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demand_empty_rest_of_line ();
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if (num < 1)
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{
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as_bad (_("file number less than one"));
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return;
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}
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if (num < (int) files_in_use && files[num].filename != 0)
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{
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as_bad (_("file number %ld already allocated"), (long) num);
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return;
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}
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if (num >= (int) files_allocated)
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{
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unsigned int old = files_allocated;
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files_allocated = num + 16;
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files = (struct file_entry *)
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xrealloc (files, (num + 16) * sizeof (struct file_entry));
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/* Zero the new memory. */
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memset (files + old, 0, (num + 16 - old) * sizeof (struct file_entry));
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}
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files[num].filename = filename;
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files[num].dir = 0;
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files_in_use = num + 1;
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}
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void
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dwarf2_directive_loc (dummy)
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int dummy ATTRIBUTE_UNUSED;
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{
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offsetT filenum, line, column;
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filenum = get_absolute_expression ();
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SKIP_WHITESPACE ();
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line = get_absolute_expression ();
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SKIP_WHITESPACE ();
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column = get_absolute_expression ();
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demand_empty_rest_of_line ();
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if (filenum < 1)
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{
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as_bad (_("file number less than one"));
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return;
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}
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if (filenum >= (int) files_in_use || files[filenum].filename == 0)
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{
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as_bad (_("unassigned file number %ld"), (long) filenum);
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return;
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}
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current.filenum = filenum;
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current.line = line;
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current.column = column;
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current.flags = DWARF2_FLAG_BEGIN_STMT;
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loc_directive_seen = true;
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#ifndef NO_LISTING
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if (listing)
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listing_source_line (line);
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#endif
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}
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static struct frag *
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first_frag_for_seg (seg)
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segT seg;
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{
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frchainS *f, *first = NULL;
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|
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for (f = frchain_root; f; f = f->frch_next)
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if (f->frch_seg == seg
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&& (! first || first->frch_subseg > f->frch_subseg))
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first = f;
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return first ? first->frch_root : NULL;
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}
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|
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static struct frag *
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last_frag_for_seg (seg)
|
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segT seg;
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{
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frchainS *f, *last = NULL;
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|
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for (f = frchain_root; f; f = f->frch_next)
|
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if (f->frch_seg == seg
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&& (! last || last->frch_subseg < f->frch_subseg))
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last= f;
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|
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return last ? last->frch_last : NULL;
|
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}
|
||
|
||
/* Emit a single byte into the current segment. */
|
||
|
||
static inline void
|
||
out_byte (byte)
|
||
int byte;
|
||
{
|
||
FRAG_APPEND_1_CHAR (byte);
|
||
}
|
||
|
||
/* Emit a statement program opcode into the current segment. */
|
||
|
||
static inline void
|
||
out_opcode (opc)
|
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int opc;
|
||
{
|
||
out_byte (opc);
|
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}
|
||
|
||
/* Emit a two-byte word into the current segment. */
|
||
|
||
static inline void
|
||
out_two (data)
|
||
int data;
|
||
{
|
||
md_number_to_chars (frag_more (2), data, 2);
|
||
}
|
||
|
||
/* Emit a four byte word into the current segment. */
|
||
|
||
static inline void
|
||
out_four (data)
|
||
int data;
|
||
{
|
||
md_number_to_chars (frag_more (4), data, 4);
|
||
}
|
||
|
||
/* Emit an unsigned "little-endian base 128" number. */
|
||
|
||
static void
|
||
out_uleb128 (value)
|
||
addressT value;
|
||
{
|
||
output_leb128 (frag_more (sizeof_leb128 (value, 0)), value, 0);
|
||
}
|
||
|
||
/* Emit a tuple for .debug_abbrev. */
|
||
|
||
static inline void
|
||
out_abbrev (name, form)
|
||
int name, form;
|
||
{
|
||
out_uleb128 (name);
|
||
out_uleb128 (form);
|
||
}
|
||
|
||
/* Create a new fake symbol whose value is the current position. */
|
||
|
||
static symbolS *
|
||
symbol_new_now ()
|
||
{
|
||
return symbol_new (fake_label_name, now_seg, frag_now_fix (), frag_now);
|
||
}
|
||
|
||
/* Set the value of SYM to the current position in the current segment. */
|
||
|
||
static void
|
||
set_symbol_value_now (sym)
|
||
symbolS *sym;
|
||
{
|
||
S_SET_SEGMENT (sym, now_seg);
|
||
S_SET_VALUE (sym, frag_now_fix ());
|
||
symbol_set_frag (sym, frag_now);
|
||
}
|
||
|
||
/* Get the size of a fragment. */
|
||
|
||
static offsetT
|
||
get_frag_fix (frag)
|
||
fragS *frag;
|
||
{
|
||
frchainS *fr;
|
||
|
||
if (frag->fr_next)
|
||
return frag->fr_fix;
|
||
|
||
/* If a fragment is the last in the chain, special measures must be
|
||
taken to find its size before relaxation, since it may be pending
|
||
on some subsegment chain. */
|
||
for (fr = frchain_root; fr; fr = fr->frch_next)
|
||
if (fr->frch_last == frag)
|
||
{
|
||
long align_mask = -1 << get_recorded_alignment (fr->frch_seg);
|
||
return (((char *) obstack_next_free (&fr->frch_obstack)
|
||
- frag->fr_literal) + ~align_mask) & align_mask;
|
||
}
|
||
|
||
abort ();
|
||
}
|
||
|
||
/* Set an absolute address (may result in a relocation entry). */
|
||
|
||
static void
|
||
out_set_addr (seg, frag, ofs)
|
||
segT seg;
|
||
fragS *frag;
|
||
addressT ofs;
|
||
{
|
||
expressionS expr;
|
||
symbolS *sym;
|
||
|
||
sym = symbol_new (fake_label_name, seg, ofs, frag);
|
||
|
||
out_opcode (DW_LNS_extended_op);
|
||
out_uleb128 (sizeof_address + 1);
|
||
|
||
out_opcode (DW_LNE_set_address);
|
||
expr.X_op = O_symbol;
|
||
expr.X_add_symbol = sym;
|
||
expr.X_add_number = 0;
|
||
emit_expr (&expr, sizeof_address);
|
||
}
|
||
|
||
/* Encode a pair of line and address skips as efficiently as possible.
|
||
Note that the line skip is signed, whereas the address skip is unsigned.
|
||
|
||
The following two routines *must* be kept in sync. This is
|
||
enforced by making emit_inc_line_addr abort if we do not emit
|
||
exactly the expected number of bytes. */
|
||
|
||
static int
|
||
size_inc_line_addr (line_delta, addr_delta)
|
||
int line_delta;
|
||
addressT addr_delta;
|
||
{
|
||
unsigned int tmp, opcode;
|
||
int len = 0;
|
||
|
||
/* Scale the address delta by the minimum instruction length. */
|
||
#if DWARF2_LINE_MIN_INSN_LENGTH > 1
|
||
assert (addr_delta % DWARF2_LINE_MIN_INSN_LENGTH == 0);
|
||
addr_delta /= DWARF2_LINE_MIN_INSN_LENGTH;
|
||
#endif
|
||
|
||
/* INT_MAX is a signal that this is actually a DW_LNE_end_sequence.
|
||
We cannot use special opcodes here, since we want the end_sequence
|
||
to emit the matrix entry. */
|
||
if (line_delta == INT_MAX)
|
||
{
|
||
if (addr_delta == MAX_SPECIAL_ADDR_DELTA)
|
||
len = 1;
|
||
else
|
||
len = 1 + sizeof_leb128 (addr_delta, 0);
|
||
return len + 3;
|
||
}
|
||
|
||
/* Bias the line delta by the base. */
|
||
tmp = line_delta - DWARF2_LINE_BASE;
|
||
|
||
/* If the line increment is out of range of a special opcode, we
|
||
must encode it with DW_LNS_advance_line. */
|
||
if (tmp >= DWARF2_LINE_RANGE)
|
||
{
|
||
len = 1 + sizeof_leb128 (line_delta, 1);
|
||
line_delta = 0;
|
||
tmp = 0 - DWARF2_LINE_BASE;
|
||
}
|
||
|
||
/* Bias the opcode by the special opcode base. */
|
||
tmp += DWARF2_LINE_OPCODE_BASE;
|
||
|
||
/* Avoid overflow when addr_delta is large. */
|
||
if (addr_delta < 256 + MAX_SPECIAL_ADDR_DELTA)
|
||
{
|
||
/* Try using a special opcode. */
|
||
opcode = tmp + addr_delta * DWARF2_LINE_RANGE;
|
||
if (opcode <= 255)
|
||
return len + 1;
|
||
|
||
/* Try using DW_LNS_const_add_pc followed by special op. */
|
||
opcode = tmp + (addr_delta - MAX_SPECIAL_ADDR_DELTA) * DWARF2_LINE_RANGE;
|
||
if (opcode <= 255)
|
||
return len + 2;
|
||
}
|
||
|
||
/* Otherwise use DW_LNS_advance_pc. */
|
||
len += 1 + sizeof_leb128 (addr_delta, 0);
|
||
|
||
/* DW_LNS_copy or special opcode. */
|
||
len += 1;
|
||
|
||
return len;
|
||
}
|
||
|
||
static void
|
||
emit_inc_line_addr (line_delta, addr_delta, p, len)
|
||
int line_delta;
|
||
addressT addr_delta;
|
||
char *p;
|
||
int len;
|
||
{
|
||
unsigned int tmp, opcode;
|
||
int need_copy = 0;
|
||
char *end = p + len;
|
||
|
||
#if DWARF2_LINE_MIN_INSN_LENGTH > 1
|
||
/* Scale the address delta by the minimum instruction length. */
|
||
assert (addr_delta % DWARF2_LINE_MIN_INSN_LENGTH == 0);
|
||
addr_delta /= DWARF2_LINE_MIN_INSN_LENGTH;
|
||
#endif
|
||
/* INT_MAX is a signal that this is actually a DW_LNE_end_sequence.
|
||
We cannot use special opcodes here, since we want the end_sequence
|
||
to emit the matrix entry. */
|
||
if (line_delta == INT_MAX)
|
||
{
|
||
if (addr_delta == MAX_SPECIAL_ADDR_DELTA)
|
||
*p++ = DW_LNS_const_add_pc;
|
||
else
|
||
{
|
||
*p++ = DW_LNS_advance_pc;
|
||
p += output_leb128 (p, addr_delta, 0);
|
||
}
|
||
|
||
*p++ = DW_LNS_extended_op;
|
||
*p++ = 1;
|
||
*p++ = DW_LNE_end_sequence;
|
||
goto done;
|
||
}
|
||
|
||
/* Bias the line delta by the base. */
|
||
tmp = line_delta - DWARF2_LINE_BASE;
|
||
|
||
/* If the line increment is out of range of a special opcode, we
|
||
must encode it with DW_LNS_advance_line. */
|
||
if (tmp >= DWARF2_LINE_RANGE)
|
||
{
|
||
*p++ = DW_LNS_advance_line;
|
||
p += output_leb128 (p, line_delta, 1);
|
||
|
||
/* Prettier, I think, to use DW_LNS_copy instead of a
|
||
"line +0, addr +0" special opcode. */
|
||
if (addr_delta == 0)
|
||
{
|
||
*p++ = DW_LNS_copy;
|
||
goto done;
|
||
}
|
||
|
||
line_delta = 0;
|
||
tmp = 0 - DWARF2_LINE_BASE;
|
||
need_copy = 1;
|
||
}
|
||
|
||
/* Bias the opcode by the special opcode base. */
|
||
tmp += DWARF2_LINE_OPCODE_BASE;
|
||
|
||
/* Avoid overflow when addr_delta is large. */
|
||
if (addr_delta < 256 + MAX_SPECIAL_ADDR_DELTA)
|
||
{
|
||
/* Try using a special opcode. */
|
||
opcode = tmp + addr_delta * DWARF2_LINE_RANGE;
|
||
if (opcode <= 255)
|
||
{
|
||
*p++ = opcode;
|
||
goto done;
|
||
}
|
||
|
||
/* Try using DW_LNS_const_add_pc followed by special op. */
|
||
opcode = tmp + (addr_delta - MAX_SPECIAL_ADDR_DELTA) * DWARF2_LINE_RANGE;
|
||
if (opcode <= 255)
|
||
{
|
||
*p++ = DW_LNS_const_add_pc;
|
||
*p++ = opcode;
|
||
goto done;
|
||
}
|
||
}
|
||
|
||
/* Otherwise use DW_LNS_advance_pc. */
|
||
*p++ = DW_LNS_advance_pc;
|
||
p += output_leb128 (p, addr_delta, 0);
|
||
|
||
if (need_copy)
|
||
*p++ = DW_LNS_copy;
|
||
else
|
||
*p++ = tmp;
|
||
|
||
done:
|
||
assert (p == end);
|
||
}
|
||
|
||
/* Handy routine to combine calls to the above two routines. */
|
||
|
||
static void
|
||
out_inc_line_addr (line_delta, addr_delta)
|
||
int line_delta;
|
||
addressT addr_delta;
|
||
{
|
||
int len = size_inc_line_addr (line_delta, addr_delta);
|
||
emit_inc_line_addr (line_delta, addr_delta, frag_more (len), len);
|
||
}
|
||
|
||
/* Generate a variant frag that we can use to relax address/line
|
||
increments between fragments of the target segment. */
|
||
|
||
static void
|
||
relax_inc_line_addr (line_delta, seg, to_frag, to_ofs, from_frag, from_ofs)
|
||
int line_delta;
|
||
segT seg;
|
||
fragS *to_frag, *from_frag;
|
||
addressT to_ofs, from_ofs;
|
||
{
|
||
symbolS *to_sym, *from_sym;
|
||
expressionS expr;
|
||
int max_chars;
|
||
|
||
to_sym = symbol_new (fake_label_name, seg, to_ofs, to_frag);
|
||
from_sym = symbol_new (fake_label_name, seg, from_ofs, from_frag);
|
||
|
||
expr.X_op = O_subtract;
|
||
expr.X_add_symbol = to_sym;
|
||
expr.X_op_symbol = from_sym;
|
||
expr.X_add_number = 0;
|
||
|
||
/* The maximum size of the frag is the line delta with a maximum
|
||
sized address delta. */
|
||
max_chars = size_inc_line_addr (line_delta, -DWARF2_LINE_MIN_INSN_LENGTH);
|
||
|
||
frag_var (rs_dwarf2dbg, max_chars, max_chars, 1,
|
||
make_expr_symbol (&expr), line_delta, NULL);
|
||
}
|
||
|
||
/* The function estimates the size of a rs_dwarf2dbg variant frag
|
||
based on the current values of the symbols. It is called before
|
||
the relaxation loop. We set fr_subtype to the expected length. */
|
||
|
||
int
|
||
dwarf2dbg_estimate_size_before_relax (frag)
|
||
fragS *frag;
|
||
{
|
||
offsetT addr_delta;
|
||
int size;
|
||
|
||
addr_delta = resolve_symbol_value (frag->fr_symbol);
|
||
size = size_inc_line_addr (frag->fr_offset, addr_delta);
|
||
|
||
frag->fr_subtype = size;
|
||
|
||
return size;
|
||
}
|
||
|
||
/* This function relaxes a rs_dwarf2dbg variant frag based on the
|
||
current values of the symbols. fr_subtype is the current length
|
||
of the frag. This returns the change in frag length. */
|
||
|
||
int
|
||
dwarf2dbg_relax_frag (frag)
|
||
fragS *frag;
|
||
{
|
||
int old_size, new_size;
|
||
|
||
old_size = frag->fr_subtype;
|
||
new_size = dwarf2dbg_estimate_size_before_relax (frag);
|
||
|
||
return new_size - old_size;
|
||
}
|
||
|
||
/* This function converts a rs_dwarf2dbg variant frag into a normal
|
||
fill frag. This is called after all relaxation has been done.
|
||
fr_subtype will be the desired length of the frag. */
|
||
|
||
void
|
||
dwarf2dbg_convert_frag (frag)
|
||
fragS *frag;
|
||
{
|
||
offsetT addr_diff;
|
||
|
||
addr_diff = resolve_symbol_value (frag->fr_symbol);
|
||
|
||
/* fr_var carries the max_chars that we created the fragment with.
|
||
fr_subtype carries the current expected length. We must, of
|
||
course, have allocated enough memory earlier. */
|
||
assert (frag->fr_var >= (int) frag->fr_subtype);
|
||
|
||
emit_inc_line_addr (frag->fr_offset, addr_diff,
|
||
frag->fr_literal + frag->fr_fix, frag->fr_subtype);
|
||
|
||
frag->fr_fix += frag->fr_subtype;
|
||
frag->fr_type = rs_fill;
|
||
frag->fr_var = 0;
|
||
frag->fr_offset = 0;
|
||
}
|
||
|
||
/* Generate .debug_line content for the chain of line number entries
|
||
beginning at E, for segment SEG. */
|
||
|
||
static void
|
||
process_entries (seg, e)
|
||
segT seg;
|
||
struct line_entry *e;
|
||
{
|
||
unsigned filenum = 1;
|
||
unsigned line = 1;
|
||
unsigned column = 0;
|
||
unsigned flags = DWARF2_LINE_DEFAULT_IS_STMT ? DWARF2_FLAG_BEGIN_STMT : 0;
|
||
fragS *frag = NULL;
|
||
fragS *last_frag;
|
||
addressT frag_ofs = 0;
|
||
addressT last_frag_ofs;
|
||
struct line_entry *next;
|
||
|
||
while (e)
|
||
{
|
||
int changed = 0;
|
||
|
||
if (filenum != e->loc.filenum)
|
||
{
|
||
filenum = e->loc.filenum;
|
||
out_opcode (DW_LNS_set_file);
|
||
out_uleb128 (filenum);
|
||
changed = 1;
|
||
}
|
||
|
||
if (column != e->loc.column)
|
||
{
|
||
column = e->loc.column;
|
||
out_opcode (DW_LNS_set_column);
|
||
out_uleb128 (column);
|
||
changed = 1;
|
||
}
|
||
|
||
if ((e->loc.flags ^ flags) & DWARF2_FLAG_BEGIN_STMT)
|
||
{
|
||
flags = e->loc.flags;
|
||
out_opcode (DW_LNS_negate_stmt);
|
||
changed = 1;
|
||
}
|
||
|
||
if (e->loc.flags & DWARF2_FLAG_BEGIN_BLOCK)
|
||
{
|
||
out_opcode (DW_LNS_set_basic_block);
|
||
changed = 1;
|
||
}
|
||
|
||
/* Don't try to optimize away redundant entries; gdb wants two
|
||
entries for a function where the code starts on the same line as
|
||
the {, and there's no way to identify that case here. Trust gcc
|
||
to optimize appropriately. */
|
||
if (1 /* line != e->loc.line || changed */)
|
||
{
|
||
int line_delta = e->loc.line - line;
|
||
if (frag == NULL)
|
||
{
|
||
out_set_addr (seg, e->frag, e->frag_ofs);
|
||
out_inc_line_addr (line_delta, 0);
|
||
}
|
||
else if (frag == e->frag)
|
||
out_inc_line_addr (line_delta, e->frag_ofs - frag_ofs);
|
||
else
|
||
relax_inc_line_addr (line_delta, seg, e->frag, e->frag_ofs,
|
||
frag, frag_ofs);
|
||
|
||
frag = e->frag;
|
||
frag_ofs = e->frag_ofs;
|
||
line = e->loc.line;
|
||
}
|
||
else if (frag == NULL)
|
||
{
|
||
out_set_addr (seg, e->frag, e->frag_ofs);
|
||
frag = e->frag;
|
||
frag_ofs = e->frag_ofs;
|
||
}
|
||
|
||
next = e->next;
|
||
free (e);
|
||
e = next;
|
||
}
|
||
|
||
/* Emit a DW_LNE_end_sequence for the end of the section. */
|
||
last_frag = last_frag_for_seg (seg);
|
||
last_frag_ofs = get_frag_fix (last_frag);
|
||
if (frag == last_frag)
|
||
out_inc_line_addr (INT_MAX, last_frag_ofs - frag_ofs);
|
||
else
|
||
relax_inc_line_addr (INT_MAX, seg, last_frag, last_frag_ofs,
|
||
frag, frag_ofs);
|
||
}
|
||
|
||
/* Emit the directory and file tables for .debug_line. */
|
||
|
||
static void
|
||
out_file_list ()
|
||
{
|
||
size_t size;
|
||
char *cp;
|
||
unsigned int i;
|
||
|
||
/* Terminate directory list. */
|
||
out_byte ('\0');
|
||
|
||
for (i = 1; i < files_in_use; ++i)
|
||
{
|
||
if (files[i].filename == NULL)
|
||
{
|
||
as_bad (_("unassigned file number %ld"), (long) i);
|
||
continue;
|
||
}
|
||
|
||
size = strlen (files[i].filename) + 1;
|
||
cp = frag_more (size);
|
||
memcpy (cp, files[i].filename, size);
|
||
|
||
out_uleb128 (files[i].dir); /* directory number */
|
||
out_uleb128 (0); /* last modification timestamp */
|
||
out_uleb128 (0); /* filesize */
|
||
}
|
||
|
||
/* Terminate filename list. */
|
||
out_byte (0);
|
||
}
|
||
|
||
/* Emit the collected .debug_line data. */
|
||
|
||
static void
|
||
out_debug_line (line_seg)
|
||
segT line_seg;
|
||
{
|
||
expressionS expr;
|
||
symbolS *line_start;
|
||
symbolS *prologue_end;
|
||
symbolS *line_end;
|
||
struct line_seg *s;
|
||
|
||
subseg_set (line_seg, 0);
|
||
|
||
line_start = symbol_new_now ();
|
||
prologue_end = symbol_make (fake_label_name);
|
||
line_end = symbol_make (fake_label_name);
|
||
|
||
/* Total length of the information for this compilation unit. */
|
||
expr.X_op = O_subtract;
|
||
expr.X_add_symbol = line_end;
|
||
expr.X_op_symbol = line_start;
|
||
expr.X_add_number = -4;
|
||
emit_expr (&expr, 4);
|
||
|
||
/* Version. */
|
||
out_two (2);
|
||
|
||
/* Length of the prologue following this length. */
|
||
expr.X_op = O_subtract;
|
||
expr.X_add_symbol = prologue_end;
|
||
expr.X_op_symbol = line_start;
|
||
expr.X_add_number = - (4 + 2 + 4);
|
||
emit_expr (&expr, 4);
|
||
|
||
/* Parameters of the state machine. */
|
||
out_byte (DWARF2_LINE_MIN_INSN_LENGTH);
|
||
out_byte (DWARF2_LINE_DEFAULT_IS_STMT);
|
||
out_byte (DWARF2_LINE_BASE);
|
||
out_byte (DWARF2_LINE_RANGE);
|
||
out_byte (DWARF2_LINE_OPCODE_BASE);
|
||
|
||
/* Standard opcode lengths. */
|
||
out_byte (0); /* DW_LNS_copy */
|
||
out_byte (1); /* DW_LNS_advance_pc */
|
||
out_byte (1); /* DW_LNS_advance_line */
|
||
out_byte (1); /* DW_LNS_set_file */
|
||
out_byte (1); /* DW_LNS_set_column */
|
||
out_byte (0); /* DW_LNS_negate_stmt */
|
||
out_byte (0); /* DW_LNS_set_basic_block */
|
||
out_byte (0); /* DW_LNS_const_add_pc */
|
||
out_byte (1); /* DW_LNS_fixed_advance_pc */
|
||
|
||
out_file_list ();
|
||
|
||
set_symbol_value_now (prologue_end);
|
||
|
||
/* For each section, emit a statement program. */
|
||
for (s = all_segs; s; s = s->next)
|
||
process_entries (s->seg, s->head->head);
|
||
|
||
set_symbol_value_now (line_end);
|
||
}
|
||
|
||
/* Emit data for .debug_aranges. */
|
||
|
||
static void
|
||
out_debug_aranges (aranges_seg, info_seg)
|
||
segT aranges_seg;
|
||
segT info_seg;
|
||
{
|
||
unsigned int addr_size = sizeof_address;
|
||
addressT size, skip;
|
||
struct line_seg *s;
|
||
expressionS expr;
|
||
char *p;
|
||
|
||
size = 4 + 2 + 4 + 1 + 1;
|
||
|
||
skip = 2 * addr_size - (size & (2 * addr_size - 1));
|
||
if (skip == 2 * addr_size)
|
||
skip = 0;
|
||
size += skip;
|
||
|
||
for (s = all_segs; s; s = s->next)
|
||
size += 2 * addr_size;
|
||
|
||
size += 2 * addr_size;
|
||
|
||
subseg_set (aranges_seg, 0);
|
||
|
||
/* Length of the compilation unit. */
|
||
out_four (size - 4);
|
||
|
||
/* Version. */
|
||
out_two (2);
|
||
|
||
/* Offset to .debug_info. */
|
||
expr.X_op = O_symbol;
|
||
expr.X_add_symbol = section_symbol (info_seg);
|
||
expr.X_add_number = 0;
|
||
emit_expr (&expr, 4);
|
||
|
||
/* Size of an address (offset portion). */
|
||
out_byte (addr_size);
|
||
|
||
/* Size of a segment descriptor. */
|
||
out_byte (0);
|
||
|
||
/* Align the header. */
|
||
if (skip)
|
||
frag_align (ffs (2 * addr_size) - 1, 0, 0);
|
||
|
||
for (s = all_segs; s; s = s->next)
|
||
{
|
||
fragS *frag;
|
||
symbolS *beg, *end;
|
||
|
||
frag = first_frag_for_seg (s->seg);
|
||
beg = symbol_new (fake_label_name, s->seg, 0, frag);
|
||
s->text_start = beg;
|
||
|
||
frag = last_frag_for_seg (s->seg);
|
||
end = symbol_new (fake_label_name, s->seg, get_frag_fix (frag), frag);
|
||
s->text_end = end;
|
||
|
||
expr.X_op = O_symbol;
|
||
expr.X_add_symbol = beg;
|
||
expr.X_add_number = 0;
|
||
emit_expr (&expr, addr_size);
|
||
|
||
expr.X_op = O_subtract;
|
||
expr.X_add_symbol = end;
|
||
expr.X_op_symbol = beg;
|
||
expr.X_add_number = 0;
|
||
emit_expr (&expr, addr_size);
|
||
}
|
||
|
||
p = frag_more (2 * addr_size);
|
||
md_number_to_chars (p, 0, addr_size);
|
||
md_number_to_chars (p + addr_size, 0, addr_size);
|
||
}
|
||
|
||
/* Emit data for .debug_abbrev. Note that this must be kept in
|
||
sync with out_debug_info below. */
|
||
|
||
static void
|
||
out_debug_abbrev (abbrev_seg)
|
||
segT abbrev_seg;
|
||
{
|
||
subseg_set (abbrev_seg, 0);
|
||
|
||
out_uleb128 (1);
|
||
out_uleb128 (DW_TAG_compile_unit);
|
||
out_byte (DW_CHILDREN_no);
|
||
out_abbrev (DW_AT_stmt_list, DW_FORM_data4);
|
||
if (all_segs->next == NULL)
|
||
{
|
||
out_abbrev (DW_AT_low_pc, DW_FORM_addr);
|
||
out_abbrev (DW_AT_high_pc, DW_FORM_addr);
|
||
}
|
||
out_abbrev (DW_AT_comp_dir, DW_FORM_string);
|
||
out_abbrev (DW_AT_producer, DW_FORM_string);
|
||
out_abbrev (DW_AT_language, DW_FORM_data2);
|
||
out_abbrev (0, 0);
|
||
|
||
/* Terminate the abbreviations for this compilation unit. */
|
||
out_byte (0);
|
||
}
|
||
|
||
/* Emit a description of this compilation unit for .debug_info. */
|
||
|
||
static void
|
||
out_debug_info (info_seg, abbrev_seg, line_seg)
|
||
segT info_seg;
|
||
segT abbrev_seg;
|
||
segT line_seg;
|
||
{
|
||
char producer[128];
|
||
char *comp_dir;
|
||
expressionS expr;
|
||
symbolS *info_start;
|
||
symbolS *info_end;
|
||
char *p;
|
||
int len;
|
||
|
||
subseg_set (info_seg, 0);
|
||
|
||
info_start = symbol_new_now ();
|
||
info_end = symbol_make (fake_label_name);
|
||
|
||
/* Compilation Unit length. */
|
||
expr.X_op = O_subtract;
|
||
expr.X_add_symbol = info_end;
|
||
expr.X_op_symbol = info_start;
|
||
expr.X_add_number = -4;
|
||
emit_expr (&expr, 4);
|
||
|
||
/* DWARF version. */
|
||
out_two (2);
|
||
|
||
/* .debug_abbrev offset */
|
||
expr.X_op = O_symbol;
|
||
expr.X_add_symbol = section_symbol (abbrev_seg);
|
||
expr.X_add_number = 0;
|
||
emit_expr (&expr, 4);
|
||
|
||
/* Target address size. */
|
||
out_byte (sizeof_address);
|
||
|
||
/* DW_TAG_compile_unit DIE abbrev */
|
||
out_uleb128 (1);
|
||
|
||
/* DW_AT_stmt_list */
|
||
expr.X_op = O_symbol;
|
||
expr.X_add_symbol = section_symbol (line_seg);
|
||
expr.X_add_number = 0;
|
||
emit_expr (&expr, 4);
|
||
|
||
/* These two attributes may only be emitted if all of the code is
|
||
contiguous. Multiple sections are not that. */
|
||
if (all_segs->next == NULL)
|
||
{
|
||
/* DW_AT_low_pc */
|
||
expr.X_op = O_symbol;
|
||
expr.X_add_symbol = all_segs->text_start;
|
||
expr.X_add_number = 0;
|
||
emit_expr (&expr, sizeof_address);
|
||
|
||
/* DW_AT_high_pc */
|
||
expr.X_op = O_symbol;
|
||
expr.X_add_symbol = all_segs->text_end;
|
||
expr.X_add_number = 0;
|
||
emit_expr (&expr, sizeof_address);
|
||
}
|
||
|
||
/* DW_AT_comp_dir */
|
||
comp_dir = getpwd ();
|
||
len = strlen (comp_dir) + 1;
|
||
p = frag_more (len);
|
||
memcpy (p, comp_dir, len);
|
||
|
||
/* DW_AT_producer */
|
||
sprintf (producer, "GNU AS %s", VERSION);
|
||
len = strlen (producer) + 1;
|
||
p = frag_more (len);
|
||
memcpy (p, producer, len);
|
||
|
||
/* DW_AT_language. Yes, this is probably not really MIPS, but the
|
||
dwarf2 draft has no standard code for assembler. */
|
||
out_two (DW_LANG_Mips_Assembler);
|
||
|
||
set_symbol_value_now (info_end);
|
||
}
|
||
|
||
void
|
||
dwarf2_finish ()
|
||
{
|
||
segT line_seg;
|
||
struct line_seg *s;
|
||
|
||
/* If no debug information was recorded, nothing to do. */
|
||
if (all_segs == NULL && files_in_use <= 1)
|
||
return;
|
||
|
||
/* Calculate the size of an address for the target machine. */
|
||
sizeof_address = bfd_arch_bits_per_address (stdoutput) / 8;
|
||
|
||
/* Create and switch to the line number section. */
|
||
line_seg = subseg_new (".debug_line", 0);
|
||
bfd_set_section_flags (stdoutput, line_seg, SEC_READONLY);
|
||
|
||
/* For each subsection, chain the debug entries together. */
|
||
for (s = all_segs; s; s = s->next)
|
||
{
|
||
struct line_subseg *ss = s->head;
|
||
struct line_entry **ptail = ss->ptail;
|
||
|
||
while ((ss = ss->next) != NULL)
|
||
{
|
||
*ptail = ss->head;
|
||
ptail = ss->ptail;
|
||
}
|
||
}
|
||
|
||
out_debug_line (line_seg);
|
||
|
||
/* If this is assembler generated line info, we need .debug_info
|
||
and .debug_abbrev sections as well. */
|
||
if (all_segs != NULL && debug_type == DEBUG_DWARF2)
|
||
{
|
||
segT abbrev_seg;
|
||
segT info_seg;
|
||
segT aranges_seg;
|
||
|
||
info_seg = subseg_new (".debug_info", 0);
|
||
abbrev_seg = subseg_new (".debug_abbrev", 0);
|
||
aranges_seg = subseg_new (".debug_aranges", 0);
|
||
|
||
bfd_set_section_flags (stdoutput, info_seg, SEC_READONLY);
|
||
bfd_set_section_flags (stdoutput, abbrev_seg, SEC_READONLY);
|
||
bfd_set_section_flags (stdoutput, aranges_seg, SEC_READONLY);
|
||
|
||
record_alignment (aranges_seg, ffs (2 * sizeof_address) - 1);
|
||
|
||
out_debug_aranges (aranges_seg, info_seg);
|
||
out_debug_abbrev (abbrev_seg);
|
||
out_debug_info (info_seg, abbrev_seg, line_seg);
|
||
}
|
||
}
|
||
|
||
#else
|
||
void
|
||
dwarf2_finish ()
|
||
{
|
||
}
|
||
|
||
int
|
||
dwarf2dbg_estimate_size_before_relax (frag)
|
||
fragS *frag ATTRIBUTE_UNUSED;
|
||
{
|
||
as_fatal (_("dwarf2 is not supported for this object file format"));
|
||
return 0;
|
||
}
|
||
|
||
int
|
||
dwarf2dbg_relax_frag (frag)
|
||
fragS *frag ATTRIBUTE_UNUSED;
|
||
{
|
||
as_fatal (_("dwarf2 is not supported for this object file format"));
|
||
return 0;
|
||
}
|
||
|
||
void
|
||
dwarf2dbg_convert_frag (frag)
|
||
fragS *frag ATTRIBUTE_UNUSED;
|
||
{
|
||
as_fatal (_("dwarf2 is not supported for this object file format"));
|
||
}
|
||
|
||
void
|
||
dwarf2_emit_insn (size)
|
||
int size ATTRIBUTE_UNUSED;
|
||
{
|
||
}
|
||
|
||
void
|
||
dwarf2_directive_file (dummy)
|
||
int dummy ATTRIBUTE_UNUSED;
|
||
{
|
||
s_app_file (0);
|
||
}
|
||
|
||
void
|
||
dwarf2_directive_loc (dummy)
|
||
int dummy ATTRIBUTE_UNUSED;
|
||
{
|
||
as_fatal (_("dwarf2 is not supported for this object file format"));
|
||
}
|
||
#endif /* BFD_ASSEMBLER */
|