/* dwarf2dbg.c - DWARF2 debug support
- Copyright (C) 1999 Free Software Foundation, Inc.
+ Copyright (C) 1999, 2000 Free Software Foundation, Inc.
Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
This file is part of GAS, the GNU Assembler.
is not made available by the GCC front-end. */
#define DWARF2_LINE_DEFAULT_IS_STMT 1
-/* Given a special op, return the line skip amount: */
+/* Given a special op, return the line skip amount. */
#define SPECIAL_LINE(op) \
(((op) - DWARF2_LINE_OPCODE_BASE)%DWARF2_LINE_RANGE + DWARF2_LINE_BASE)
DWARF2_LINE_MIN_INSN_LENGTH. */
#define SPECIAL_ADDR(op) (((op) - DWARF2_LINE_OPCODE_BASE)/DWARF2_LINE_RANGE)
-/* The maximum address skip amont that can be encoded with a special op: */
+/* The maximum address skip amount that can be encoded with a special op. */
#define MAX_SPECIAL_ADDR_DELTA SPECIAL_ADDR(255)
#define INITIAL_STATE \
- /* initialize as per DWARF2.0 standard: */ \
+ /* Initialize as per DWARF2.0 standard. */ \
0, /* address */ \
1, /* file */ \
1, /* line */ \
unsigned int
any_dwarf2_directives : 1; /* did we emit any DWARF2 line debug directives? */
+ fragS * frag; /* frag that "addr" is relative to */
segT text_seg; /* text segment "addr" is relative to */
subsegT text_subseg;
segT line_seg; /* ".debug_line" segment */
}
*file;
- struct dwarf2_line_info current; /* current source info: */
+ struct dwarf2_line_info current; /* current source info */
- /* counters for statistical purposes: */
+ /* counters for statistical purposes */
unsigned int num_line_entries;
unsigned int opcode_hist[256]; /* histogram of opcode frequencies */
}
0,
0,
0,
+ 0,
NULL,
{ NULL, 0, 0, 0, 0 },
0,
}
};
-
-/* Function prototypes: */
+/* Function prototypes. */
static void out_uleb128 PARAMS ((addressT));
static void out_sleb128 PARAMS ((offsetT));
static void gen_addr_line PARAMS ((int, addressT));
static void gen_file_list PARAMS ((void));
static void print_stats PARAMS ((unsigned long));
-
#define out_byte(byte) FRAG_APPEND_1_CHAR(byte)
#define out_opcode(opc) (out_byte ((opc)), ++ls.opcode_hist[(opc) & 0xff])
/* Output an unsigned "little-endian base 128" number. */
+
static void
out_uleb128 (value)
addressT value;
}
/* Output a signed "little-endian base 128" number. */
+
static void
out_sleb128 (value)
offsetT value;
/* 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. */
+
static void
gen_addr_line (line_delta, addr_delta)
int line_delta;
tmp += DWARF2_LINE_OPCODE_BASE;
- /* try using a special opcode: */
+ /* Try using a special opcode. */
opcode = tmp + addr_delta*DWARF2_LINE_RANGE;
if (opcode <= 255)
{
return;
}
- /* try using DW_LNS_const_add_pc followed by special op: */
- opcode = tmp + (addr_delta - MAX_SPECIAL_ADDR_DELTA)*DWARF2_LINE_RANGE;
+ /* 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)
{
out_opcode (DW_LNS_const_add_pc);
out_uleb128 (addr_delta);
if (line_delta)
- out_opcode (tmp); /* output line-delta */
+ /* Output line-delta. */
+ out_opcode (tmp);
else
- out_opcode (DW_LNS_copy); /* append new row with current info */
+ /* Append new row with current info. */
+ out_opcode (DW_LNS_copy);
}
static void
ls.sm = initial_state;
}
-/* Set an absolute address (may results in a relocation entry): */
+/* Set an absolute address (may results in a relocation entry). */
+
static void
out_set_addr (addr)
addressT addr;
/* Emit DW_LNS_end_sequence and reset state machine. Does not
preserve the current segment/sub-segment! */
+
static void
out_end_sequence ()
{
addressT addr, delta;
+ fragS *text_frag;
if (ls.text_seg)
{
#else
addr = frag_now_fix ();
#endif
+ text_frag = frag_now;
subseg_set (ls.line_seg, DL_BODY);
- if (addr < ls.sm.addr)
+ if (text_frag != ls.frag)
{
out_set_addr (addr);
ls.sm.addr = addr;
+ ls.frag = text_frag;
}
else
{
- delta = addr - ls.sm.addr;
+ delta = (addr - ls.sm.addr) / DWARF2_LINE_MIN_INSN_LENGTH;
if (delta > 0)
- gen_addr_line (0, delta / DWARF2_LINE_MIN_INSN_LENGTH);
+ {
+ /* Advance address without updating the line-debug
+ matrix---the end_sequence entry is used only to tell
+ the debugger the end of the sequence. */
+ out_opcode (DW_LNS_advance_pc);
+ out_uleb128 (delta);
+ }
}
}
else
/* Look up a filenumber either by filename or by filenumber. If both
a filenumber and a filename are specified, lookup by filename takes
precedence. If the filename cannot be found, it is added to the
- filetable the filenumber for the new entry is returned. */
+ filetable and the filenumber for the new entry is returned. */
+
static int
get_filenum (filenum, file)
int filenum;
int i, last = filenum - 1;
char char0 = file[0];
- if (last >= ls.num_filenames)
+ /* If filenum is out of range of the filename table, then try using the
+ table entry returned from the previous call. */
+ if (last >= ls.num_filenames || last < 0)
last = ls.last_filename;
- /* do a quick check against the previously used filename: */
+ /* Do a quick check against the specified or previously used filenum. */
if (ls.num_filenames > 0 && ls.file[last].name[0] == char0
&& strcmp (ls.file[last].name + 1, file + 1) == 0)
return last + 1;
- /* no match, fall back to simple linear scan: */
+ /* No match, fall back to simple linear scan. */
for (i = 0; i < ls.num_filenames; ++i)
{
if (ls.file[i].name[0] == char0
}
}
- /* no match: enter new filename */
+ /* No match, enter new filename. */
if (ls.num_filenames >= ls.filename_len)
{
ls.filename_len += 13;
}
ls.file[ls.num_filenames].dir = 0;
ls.file[ls.num_filenames].name = file;
+ ls.last_filename = ls.num_filenames;
return ++ls.num_filenames;
}
+/* Emit an entry in the line number table if the address or line has changed.
+ ADDR is relative to the current frag in the text section. */
+
void
dwarf2_gen_line_info (addr, l)
addressT addr;
unsigned int any_output = 0;
subsegT saved_subseg;
segT saved_seg;
+ fragS *saved_frag;
if (flag_debug)
fprintf (stderr, "line: addr %lx file `%s' line %u col %u flags %x\n",
else if (l->filename)
filenum = get_filenum (filenum, l->filename);
else
- return; /* no filename, no filnum => no play */
+ /* No filename, no filnum => no play. */
+ return;
+
+ /* Must save these before the subseg_new call, as that call will change
+ them. */
+ saved_seg = now_seg;
+ saved_subseg = now_subseg;
+ saved_frag = frag_now;
if (!ls.line_seg)
{
/* We're going to need this symbol. */
secsym = symbol_find (".debug_line");
if (secsym != NULL)
- symbol_set_bfdsym (secsym, ls.line_seg->symbol);
+ symbol_set_bfdsym (secsym, ls.line_seg->symbol);
else
- symbol_table_insert (section_symbol (ls.line_seg));
+ symbol_table_insert (section_symbol (ls.line_seg));
#endif
}
- saved_seg = now_seg;
- saved_subseg = now_subseg;
subseg_set (ls.line_seg, DL_BODY);
if (ls.text_seg != saved_seg || ls.text_subseg != saved_subseg)
{
if (!ls.sm.empty_sequence)
{
- out_end_sequence (); /* terminate previous sequence */
+ /* Terminate previous sequence. */
+ out_end_sequence ();
ls.sm.empty_sequence = 1;
}
any_output = 1;
ls.text_subseg = saved_subseg;
out_set_addr (addr);
ls.sm.addr = addr;
+ ls.frag = saved_frag;
}
if (ls.sm.filenum != filenum)
if (ls.sm.line != l->line)
{
any_output = 1;
- if (addr < ls.sm.addr)
+ if (saved_frag != ls.frag)
{
- /* This happens when a new frag got allocated (for whatever
- reason). Deal with it by generating a reference symbol.
- Note: no end_sequence needs to be generated because the
- address did not really decrease (only the reference point
- changed).
-
- ??? Perhaps we should directly check for a change of
- frag_now instead? */
+ /* If a new frag got allocated (for whatever reason), then
+ deal with it by generating a reference symbol. Note: no
+ end_sequence needs to be generated because the address did
+ not really decrease (only the reference point changed). */
out_set_addr (addr);
ls.sm.addr = addr;
+ ls.frag = saved_frag;
}
gen_addr_line (l->line - ls.sm.line,
(addr - ls.sm.addr) / DWARF2_LINE_MIN_INSN_LENGTH);
}
if (j >= num_dirs)
{
- /* didn't find this directory: append it to the list */
+ /* Didn't find this directory: append it to the list. */
size_t size = strlen (str) + 1;
cp = frag_more (size);
memcpy (cp, str, size);
ls.file[i].name = slash + 1;
}
}
- out_byte ('\0'); /* terminate directory list */
+
+ /* Terminate directory list. */
+ out_byte ('\0');
}
static void
out_uleb128 (0); /* last modification timestamp */
out_uleb128 (0); /* filesize */
}
- out_byte (0); /* terminate filename list */
+
+ /* Terminate filename list. */
+ out_byte (0);
}
static void
fprintf (stderr, "\nStandard opcode histogram:\n");
- for (i = 0; i < sizeof (opc_name)/sizeof (opc_name[0]); ++i)
+ for (i = 0; i < sizeof (opc_name) / sizeof (opc_name[0]); ++i)
{
fprintf (stderr, "%s", opc_name[i]);
for (j = strlen (opc_name[i]); j < 16; ++j)
j = SPECIAL_LINE (i);
if (j == DWARF2_LINE_BASE)
fprintf (stderr, "\n%4u: ",
- DWARF2_LINE_MIN_INSN_LENGTH*SPECIAL_ADDR (i));
+ ((unsigned int)
+ DWARF2_LINE_MIN_INSN_LENGTH * SPECIAL_ADDR (i)));
fprintf (stderr, " %2u", ls.opcode_hist[i]);
}
fprintf (stderr, "\n");
char *cp;
if (!ls.line_seg)
- /* no .debug_line segment, no work to do... */
+ /* No .debug_line segment, no work to do. */
return;
saved_seg = now_seg;
out_end_sequence ();
total_size = body_size = frag_now_fix ();
- /* now generate the directory and file lists: */
+ /* Now generate the directory and file lists. */
subseg_set (ls.line_seg, DL_FILES);
gen_dir_list ();
gen_file_list ();
total_size += frag_now_fix ();
- /* and now the header ("statement program prolog", in DWARF2 lingo...) */
+ /* And now the header ("statement program prolog", in DWARF2 lingo...). */
subseg_set (ls.line_seg, DL_PROLOG);
cp = frag_more (15 + DWARF2_LINE_OPCODE_BASE - 1);