/* dwarf2dbg.c - DWARF2 debug support
- Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005
+ Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
Free Software Foundation, Inc.
GAS is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2, or (at your option)
+ the Free Software Foundation; either version 3, or (at your option)
any later version.
GAS is distributed in the hope that it will be useful,
[epilogue_begin] [is_stmt VALUE] [isa VALUE]
*/
-#include "ansidecl.h"
#include "as.h"
#include "safe-ctype.h"
#include "dwarf2dbg.h"
#include <filenames.h>
+#ifdef HAVE_DOS_BASED_FILE_SYSTEM
+/* We need to decide which character to use as a directory separator.
+ Just because HAVE_DOS_BASED_FILE_SYSTEM is defined, it does not
+ necessarily mean that the backslash character is the one to use.
+ Some environments, eg Cygwin, can support both naming conventions.
+ So we use the heuristic that we only need to use the backslash if
+ the path is an absolute path starting with a DOS style drive
+ selector. eg C: or D: */
+# define INSERT_DIR_SEPARATOR(string, offset) \
+ do \
+ { \
+ if (offset > 1 \
+ && string[0] != 0 \
+ && string[1] == ':') \
+ string [offset] = '\\'; \
+ else \
+ string [offset] = '/'; \
+ } \
+ while (0)
+#else
+# define INSERT_DIR_SEPARATOR(string, offset) string[offset] = '/'
+#endif
+
#ifndef DWARF2_FORMAT
# define DWARF2_FORMAT() dwarf2_format_32bit
#endif
#define DL_FILES 1
#define DL_BODY 2
+/* If linker relaxation might change offsets in the code, the DWARF special
+ opcodes and variable-length operands cannot be used. If this macro is
+ nonzero, use the DW_LNS_fixed_advance_pc opcode instead. */
+#ifndef DWARF2_USE_FIXED_ADVANCE_PC
+# define DWARF2_USE_FIXED_ADVANCE_PC 0
+#endif
+
/* First special line opcde - leave room for the standard opcodes.
Note: If you want to change this, you'll have to update the
"standard_opcode_lengths" table that is emitted below in
/* TRUE when we've seen a .loc directive recently. Used to avoid
doing work when there's nothing to do. */
-static bfd_boolean loc_directive_seen;
+bfd_boolean dwarf2_loc_directive_seen;
/* TRUE when we're supposed to set the basic block mark whenever a
label is seen. */
static void out_four (int);
static void out_abbrev (int, int);
static void out_uleb128 (addressT);
-static offsetT get_frag_fix (fragS *);
+static offsetT get_frag_fix (fragS *, segT);
static void out_set_addr (symbolS *);
static int size_inc_line_addr (int, addressT);
static void emit_inc_line_addr (int, addressT, char *, int);
+static int size_fixed_inc_line_addr (int, addressT);
+static void emit_fixed_inc_line_addr (int, addressT, fragS *, char *, int);
static void out_inc_line_addr (int, addressT);
static void relax_inc_line_addr (int, symbolS *, symbolS *);
static void process_entries (segT, struct line_entry *);
static void out_debug_line (segT);
static void out_debug_aranges (segT, segT);
static void out_debug_abbrev (segT);
-static void out_debug_info (segT, segT, segT);
\f
#ifndef TC_DWARF2_EMIT_OFFSET
-# define TC_DWARF2_EMIT_OFFSET generic_dwarf2_emit_offset
-static void generic_dwarf2_emit_offset (symbolS *, unsigned int);
+#define TC_DWARF2_EMIT_OFFSET generic_dwarf2_emit_offset
/* Create an offset to .dwarf2_*. */
static subsegT last_subseg;
static struct line_subseg *last_line_subseg;
- struct line_seg *s;
+ struct line_seg **ps, *s;
struct line_subseg **pss, *ss;
if (seg == last_seg && subseg == last_subseg)
return last_line_subseg;
- for (s = all_segs; s; s = s->next)
+ for (ps = &all_segs; (s = *ps) != NULL; ps = &s->next)
if (s->seg == seg)
goto found_seg;
s = (struct line_seg *) xmalloc (sizeof (*s));
- s->next = all_segs;
+ s->next = NULL;
s->seg = seg;
s->head = NULL;
- all_segs = s;
+ *ps = s;
found_seg:
for (pss = &s->head; (ss = *pss) != NULL ; pss = &ss->next)
{
struct dwarf2_line_info loc;
- if (loc_directive_seen)
+ if (dwarf2_loc_directive_seen)
{
/* Use the last location established by a .loc directive, not
the value returned by dwarf2_where(). That calls as_where()
or the physical input file name (foo.s) and not the file name
specified in the most recent .loc directive (eg foo.h). */
loc = current;
-
- /* Unless we generate DWARF2 debugging information for each
- assembler line, we only emit one line symbol for one LOC. */
- if (debug_type != DEBUG_DWARF2)
- loc_directive_seen = FALSE;
}
else if (debug_type != DEBUG_DWARF2)
return;
dwarf2_where (&loc);
dwarf2_gen_line_info (frag_now_fix () - size, &loc);
+ dwarf2_consume_line_info ();
+}
+
+/* Called after the current line information has been either used with
+ dwarf2_gen_line_info or saved with a machine instruction for later use.
+ This resets the state of the line number information to reflect that
+ it has been used. */
+
+void
+dwarf2_consume_line_info (void)
+{
+ /* Unless we generate DWARF2 debugging information for each
+ assembler line, we only emit one line symbol for one LOC. */
+ if (debug_type != DEBUG_DWARF2)
+ dwarf2_loc_directive_seen = FALSE;
current.flags &= ~(DWARF2_FLAG_BASIC_BLOCK
| DWARF2_FLAG_PROLOGUE_END
if (debug_type == DEBUG_DWARF2)
dwarf2_where (&loc);
else
- {
- loc = current;
- loc_directive_seen = FALSE;
- }
+ loc = current;
loc.flags |= DWARF2_FLAG_BASIC_BLOCK;
- current.flags &= ~(DWARF2_FLAG_BASIC_BLOCK
- | DWARF2_FLAG_PROLOGUE_END
- | DWARF2_FLAG_EPILOGUE_BEGIN);
-
+ dwarf2_consume_line_info ();
dwarf2_gen_line_info_1 (label, &loc);
}
files[i].filename = num ? file : xstrdup (file);
files[i].dir = dir;
- files_in_use = i + 1;
+ if (files_in_use < i + 1)
+ files_in_use = i + 1;
last_used = i;
last_used_dir_len = dir_len;
{
offsetT filenum, line;
+ /* If we see two .loc directives in a row, force the first one to be
+ output now. */
+ if (dwarf2_loc_directive_seen && debug_type != DEBUG_DWARF2)
+ dwarf2_emit_insn (0);
+
filenum = get_absolute_expression ();
SKIP_WHITESPACE ();
line = get_absolute_expression ();
char *cp = (char *) alloca (dir_len + 1 + file_len + 1);
memcpy (cp, dirs[files[filenum].dir], dir_len);
- cp[dir_len] = '/';
+ INSERT_DIR_SEPARATOR (cp, dir_len);
memcpy (cp + dir_len + 1, files[filenum].filename, file_len);
cp[dir_len + file_len + 1] = '\0';
listing_source_file (cp);
}
demand_empty_rest_of_line ();
- loc_directive_seen = TRUE;
+ dwarf2_loc_directive_seen = TRUE;
}
void
static struct frag *
first_frag_for_seg (segT seg)
{
- frchainS *f, *first = NULL;
-
- for (f = frchain_root; f; f = f->frch_next)
- if (f->frch_seg == seg
- && (! first || first->frch_subseg > f->frch_subseg))
- first = f;
-
- return first ? first->frch_root : NULL;
+ return seg_info (seg)->frchainP->frch_root;
}
static struct frag *
last_frag_for_seg (segT seg)
{
- frchainS *f, *last = NULL;
+ frchainS *f = seg_info (seg)->frchainP;
- for (f = frchain_root; f; f = f->frch_next)
- if (f->frch_seg == seg
- && (! last || last->frch_subseg < f->frch_subseg))
- last= f;
+ while (f->frch_next != NULL)
+ f = f->frch_next;
- return last ? last->frch_last : NULL;
+ return f->frch_last;
}
\f
/* Emit a single byte into the current segment. */
/* Get the size of a fragment. */
static offsetT
-get_frag_fix (fragS *frag)
+get_frag_fix (fragS *frag, segT seg)
{
frchainS *fr;
/* 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)
+ for (fr = seg_info (seg)->frchainP; fr; fr = fr->frch_next)
if (fr->frch_last == frag)
return (char *) obstack_next_free (&fr->frch_obstack) - frag->fr_literal;
emit_inc_line_addr (line_delta, addr_delta, frag_more (len), len);
}
+/* Write out an alternative form of line and address skips using
+ DW_LNS_fixed_advance_pc opcodes. This uses more space than the default
+ line and address information, but it is required if linker relaxation
+ could change the code offsets. The following two routines *must* be
+ kept in sync. */
+
+static int
+size_fixed_inc_line_addr (int line_delta, addressT addr_delta)
+{
+ int len = 0;
+
+ /* INT_MAX is a signal that this is actually a DW_LNE_end_sequence. */
+ if (line_delta != INT_MAX)
+ len = 1 + sizeof_leb128 (line_delta, 1);
+
+ if (addr_delta > 50000)
+ {
+ /* DW_LNS_extended_op */
+ len += 1 + sizeof_leb128 (sizeof_address + 1, 0);
+ /* DW_LNE_set_address */
+ len += 1 + sizeof_address;
+ }
+ else
+ /* DW_LNS_fixed_advance_pc */
+ len += 3;
+
+ if (line_delta == INT_MAX)
+ /* DW_LNS_extended_op + DW_LNE_end_sequence */
+ len += 3;
+ else
+ /* DW_LNS_copy */
+ len += 1;
+
+ return len;
+}
+
+static void
+emit_fixed_inc_line_addr (int line_delta, addressT addr_delta, fragS *frag,
+ char *p, int len)
+{
+ expressionS *exp;
+ segT line_seg;
+ char *end = p + len;
+
+ /* Line number sequences cannot go backward in addresses. This means
+ we've incorrectly ordered the statements in the sequence. */
+ assert ((offsetT) addr_delta >= 0);
+
+ /* INT_MAX is a signal that this is actually a DW_LNE_end_sequence. */
+ if (line_delta != INT_MAX)
+ {
+ *p++ = DW_LNS_advance_line;
+ p += output_leb128 (p, line_delta, 1);
+ }
+
+ exp = symbol_get_value_expression (frag->fr_symbol);
+ line_seg = subseg_get (".debug_line", 0);
+
+ /* The DW_LNS_fixed_advance_pc opcode has a 2-byte operand so it can
+ advance the address by at most 64K. Linker relaxation (without
+ which this function would not be used) could change the operand by
+ an unknown amount. If the address increment is getting close to
+ the limit, just reset the address. */
+ if (addr_delta > 50000)
+ {
+ symbolS *to_sym;
+ expressionS expr;
+
+ assert (exp->X_op = O_subtract);
+ to_sym = exp->X_add_symbol;
+
+ *p++ = DW_LNS_extended_op;
+ p += output_leb128 (p, sizeof_address + 1, 0);
+ *p++ = DW_LNE_set_address;
+ expr.X_op = O_symbol;
+ expr.X_add_symbol = to_sym;
+ expr.X_add_number = 0;
+ subseg_change (line_seg, 0);
+ emit_expr_fix (&expr, sizeof_address, frag, p);
+ p += sizeof_address;
+ }
+ else
+ {
+ *p++ = DW_LNS_fixed_advance_pc;
+ subseg_change (line_seg, 0);
+ emit_expr_fix (exp, 2, frag, p);
+ p += 2;
+ }
+
+ if (line_delta == INT_MAX)
+ {
+ *p++ = DW_LNS_extended_op;
+ *p++ = 1;
+ *p++ = DW_LNE_end_sequence;
+ }
+ else
+ *p++ = DW_LNS_copy;
+
+ assert (p == end);
+}
+
/* Generate a variant frag that we can use to relax address/line
increments between fragments of the target segment. */
/* 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);
+ if (DWARF2_USE_FIXED_ADVANCE_PC)
+ max_chars = size_fixed_inc_line_addr (line_delta,
+ -DWARF2_LINE_MIN_INSN_LENGTH);
+ else
+ 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);
int size;
addr_delta = resolve_symbol_value (frag->fr_symbol);
- size = size_inc_line_addr (frag->fr_offset, addr_delta);
+ if (DWARF2_USE_FIXED_ADVANCE_PC)
+ size = size_fixed_inc_line_addr (frag->fr_offset, addr_delta);
+ else
+ size = size_inc_line_addr (frag->fr_offset, addr_delta);
frag->fr_subtype = size;
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);
+ if (DWARF2_USE_FIXED_ADVANCE_PC)
+ emit_fixed_inc_line_addr (frag->fr_offset, addr_diff, frag,
+ frag->fr_literal + frag->fr_fix,
+ frag->fr_subtype);
+ else
+ 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;
out_set_addr (lab);
out_inc_line_addr (line_delta, 0);
}
- else if (frag == last_frag)
+ else if (frag == last_frag && ! DWARF2_USE_FIXED_ADVANCE_PC)
out_inc_line_addr (line_delta, frag_ofs - last_frag_ofs);
else
relax_inc_line_addr (line_delta, lab, last_lab);
/* Emit a DW_LNE_end_sequence for the end of the section. */
frag = last_frag_for_seg (seg);
- frag_ofs = get_frag_fix (frag);
- if (frag == last_frag)
+ frag_ofs = get_frag_fix (frag, seg);
+ if (frag == last_frag && ! DWARF2_USE_FIXED_ADVANCE_PC)
out_inc_line_addr (INT_MAX, frag_ofs - last_frag_ofs);
else
{
out_file_list (void)
{
size_t size;
+ const char *dir;
char *cp;
unsigned int i;
/* Emit directory list. */
for (i = 1; i < dirs_in_use; ++i)
{
- size = strlen (dirs[i]) + 1;
+ dir = remap_debug_filename (dirs[i]);
+ size = strlen (dir) + 1;
cp = frag_more (size);
- memcpy (cp, dirs[i], size);
+ memcpy (cp, dir, size);
}
/* Terminate it. */
out_byte ('\0');
symbol_set_value_now (line_end);
}
+static void
+out_debug_ranges (segT ranges_seg)
+{
+ unsigned int addr_size = sizeof_address;
+ struct line_seg *s;
+ expressionS expr;
+ unsigned int i;
+
+ subseg_set (ranges_seg, 0);
+
+ /* Base Address Entry. */
+ for (i = 0; i < addr_size; i++)
+ out_byte (0xff);
+ for (i = 0; i < addr_size; i++)
+ out_byte (0);
+
+ /* Range List Entry. */
+ for (s = all_segs; s; s = s->next)
+ {
+ fragS *frag;
+ symbolS *beg, *end;
+
+ frag = first_frag_for_seg (s->seg);
+ beg = symbol_temp_new (s->seg, 0, frag);
+ s->text_start = beg;
+
+ frag = last_frag_for_seg (s->seg);
+ end = symbol_temp_new (s->seg, get_frag_fix (frag, s->seg), 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_symbol;
+ expr.X_add_symbol = end;
+ expr.X_add_number = 0;
+ emit_expr (&expr, addr_size);
+ }
+
+ /* End of Range Entry. */
+ for (i = 0; i < addr_size; i++)
+ out_byte (0);
+ for (i = 0; i < addr_size; i++)
+ out_byte (0);
+}
+
/* Emit data for .debug_aranges. */
static void
s->text_start = beg;
frag = last_frag_for_seg (s->seg);
- end = symbol_temp_new (s->seg, get_frag_fix (frag), frag);
+ end = symbol_temp_new (s->seg, get_frag_fix (frag, s->seg), frag);
s->text_end = end;
expr.X_op = O_symbol;
out_abbrev (DW_AT_low_pc, DW_FORM_addr);
out_abbrev (DW_AT_high_pc, DW_FORM_addr);
}
+ else
+ {
+ if (DWARF2_FORMAT () == dwarf2_format_32bit)
+ out_abbrev (DW_AT_ranges, DW_FORM_data4);
+ else
+ out_abbrev (DW_AT_ranges, DW_FORM_data8);
+ }
out_abbrev (DW_AT_name, DW_FORM_string);
out_abbrev (DW_AT_comp_dir, DW_FORM_string);
out_abbrev (DW_AT_producer, DW_FORM_string);
/* Emit a description of this compilation unit for .debug_info. */
static void
-out_debug_info (segT info_seg, segT abbrev_seg, segT line_seg)
+out_debug_info (segT info_seg, segT abbrev_seg, segT line_seg, segT ranges_seg)
{
char producer[128];
- char *comp_dir;
+ const char *comp_dir;
+ const char *dirname;
expressionS expr;
symbolS *info_start;
symbolS *info_end;
/* ??? sizeof_offset */
TC_DWARF2_EMIT_OFFSET (section_symbol (line_seg), 4);
- /* These two attributes may only be emitted if all of the code is
- contiguous. Multiple sections are not that. */
+ /* These two attributes are emitted if all of the code is contiguous. */
if (all_segs->next == NULL)
{
/* DW_AT_low_pc */
expr.X_add_number = 0;
emit_expr (&expr, sizeof_address);
}
+ else
+ {
+ /* This attribute is emitted if the code is disjoint. */
+ /* DW_AT_ranges. */
+ TC_DWARF2_EMIT_OFFSET (section_symbol (ranges_seg), sizeof_offset);
+ }
/* DW_AT_name. We don't have the actual file name that was present
on the command line, so assume files[1] is the main input file.
abort ();
if (files[1].dir)
{
- len = strlen (dirs[files[1].dir]);
+ dirname = remap_debug_filename (dirs[files[1].dir]);
+ len = strlen (dirname);
p = frag_more (len + 1);
- memcpy (p, dirs[files[1].dir], len);
- p[len] = '/';
+ memcpy (p, dirname, len);
+ INSERT_DIR_SEPARATOR (p, len);
}
len = strlen (files[1].filename) + 1;
p = frag_more (len);
memcpy (p, files[1].filename, len);
/* DW_AT_comp_dir */
- comp_dir = getpwd ();
+ comp_dir = remap_debug_filename (getpwd ());
len = strlen (comp_dir) + 1;
p = frag_more (len);
memcpy (p, comp_dir, len);
{
segT abbrev_seg;
segT aranges_seg;
+ segT ranges_seg;
assert (all_segs);
record_alignment (aranges_seg, ffs (2 * sizeof_address) - 1);
+ if (all_segs->next == NULL)
+ ranges_seg = NULL;
+ else
+ {
+ ranges_seg = subseg_new (".debug_ranges", 0);
+ bfd_set_section_flags (stdoutput, ranges_seg,
+ SEC_READONLY | SEC_DEBUGGING);
+ record_alignment (ranges_seg, ffs (2 * sizeof_address) - 1);
+ out_debug_ranges (ranges_seg);
+ }
+
out_debug_aranges (aranges_seg, info_seg);
out_debug_abbrev (abbrev_seg);
- out_debug_info (info_seg, abbrev_seg, line_seg);
+ out_debug_info (info_seg, abbrev_seg, line_seg, ranges_seg);
}
}
projects / binutils.git / blobdiff