/* dwarf2dbg.c - DWARF2 debug support
- Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
+ Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
Free Software Foundation, Inc.
Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
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,
#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_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 *);
{
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);
}
{
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 ();
}
demand_empty_rest_of_line ();
- loc_directive_seen = TRUE;
+ dwarf2_loc_directive_seen = TRUE;
}
void
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, seg);
- if (frag == last_frag)
+ 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');
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;
}
else
{
- /* This attributes is emitted if the code is disjoint. */
-
- /* DW_AT_ranges */
- expr.X_op = O_symbol;
- expr.X_add_symbol = section_symbol (ranges_seg);
- expr.X_add_number = 0;
- emit_expr (&expr, sizeof_address);
+ /* 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
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);
+ memcpy (p, dirname, len);
INSERT_DIR_SEPARATOR (p, len);
}
len = strlen (files[1].filename) + 1;
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);
projects / deliverable / binutils-gdb.git / blobdiff