On 2019-10-18 3:31 p.m., Ali Tamur wrote:
> I've done everything asked, except this bit:
>> I'd still suggest adding a gdb_assert to verify that in the case of
> DWARF <= 4, index should be > 0.
>
> This caused failure in multiple tests, I think the correct behaviour is to
> return nullptr when DWARF <= 4 and index = 0 (done).
Oh, right, requesting the entry 0 isn't invalid, it's just that it represents the
compilation directory, which is not explicitly represented. We indeed return
NULL at the moment when requesting index 0 (it underflows the unsigned variable),
so you are right that we should continue doing that.
> @@ -20651,12 +20689,11 @@ dwarf_decode_line_header (sect_offset sect_off, struct dwarf2_cu *cu)
> Returns NULL if FILE_INDEX should be ignored, i.e., it is pst->filename. */
>
> static const char *
> -psymtab_include_file_name (const struct line_header *lh, int file_index,
> +psymtab_include_file_name (const struct line_header *lh, const file_entry &fe,
> const struct partial_symtab *pst,
> const char *comp_dir,
> gdb::unique_xmalloc_ptr<char> *name_holder)
The comment above this function says:
Return the file name of the psymtab for included file FILE_INDEX
It would need to be updated.
> @@ -24190,6 +24221,14 @@ dwarf_alloc_die (struct dwarf2_cu *cu, int num_attrs)
>
> /* Macro support. */
>
> +static bool
> +is_valid_file_index (int file_index, struct line_header *lh)
> +{
> + if (lh->version >= 5)
> + return 0 <= file_index && file_index < lh->file_names_size ();
> + return 1 <= file_index && file_index <= lh->file_names_size ();
> +}
I think it would make sense if this was a method of line_header, since it's related to
the line_header::file_name_at method.
Simon
@@ -922,13 +922,13 @@ typedef void (die_reader_func_ftype) (const struct die_reader_specs *reader,
int has_children,
void *data);
-/* A 1-based directory index. This is a strong typedef to prevent
- accidentally using a directory index as a 0-based index into an
- array/vector. */
-enum class dir_index : unsigned int {};
+/* dir_index is 1-based in DWARF 4 and before, and is 0-based in DWARF 5 and
+ later. */
+typedef int dir_index;
-/* Likewise, a 1-based file name index. */
-enum class file_name_index : unsigned int {};
+/* file_name_index is 1-based in DWARF 4 and before, and is 0-based in DWARF 5
+ and later. */
+typedef int file_name_index;
struct file_entry
{
@@ -980,32 +980,40 @@ struct line_header
void add_file_name (const char *name, dir_index d_index,
unsigned int mod_time, unsigned int length);
- /* Return the include dir at INDEX (1-based). Returns NULL if INDEX
- is out of bounds. */
+ /* Return the include dir at INDEX (0-based in DWARF 5 and 1-based before).
+ Returns NULL if INDEX is out of bounds. */
const char *include_dir_at (dir_index index) const
{
- /* Convert directory index number (1-based) to vector index
- (0-based). */
- size_t vec_index = to_underlying (index) - 1;
-
- if (vec_index >= include_dirs.size ())
+ int vec_index;
+ if (version >= 5)
+ vec_index = index;
+ else
+ vec_index = index - 1;
+ if (vec_index < 0 || vec_index >= m_include_dirs.size ())
return NULL;
- return include_dirs[vec_index];
+ return m_include_dirs[vec_index];
}
- /* Return the file name at INDEX (1-based). Returns NULL if INDEX
- is out of bounds. */
+ /* Return the file name at INDEX (0-based in DWARF 5 and 1-based before).
+ Returns NULL if INDEX is out of bounds. */
file_entry *file_name_at (file_name_index index)
{
- /* Convert file name index number (1-based) to vector index
- (0-based). */
- size_t vec_index = to_underlying (index) - 1;
-
- if (vec_index >= file_names.size ())
+ int vec_index;
+ if (version >= 5)
+ vec_index = index;
+ else
+ vec_index = index - 1;
+ if (vec_index < 0 || vec_index >= m_file_names.size ())
return NULL;
- return &file_names[vec_index];
+ return &m_file_names[vec_index];
}
+ /* The indexes are 0-based in DWARF 5 and 1-based in DWARF 4. Therefore,
+ this method should only be used to iterate through all file entries in an
+ index-agnostic manner. */
+ std::vector<file_entry> &file_names ()
+ { return m_file_names; }
+
/* Offset of line number information in .debug_line section. */
sect_offset sect_off {};
@@ -1032,12 +1040,23 @@ struct line_header
pointers. The memory is owned by debug_line_buffer. */
std::vector<const char *> include_dirs;
- /* The file_names table. */
- std::vector<file_entry> file_names;
+ int file_names_size ()
+ { return m_file_names.size(); }
/* The start and end of the statement program following this
header. These point into dwarf2_per_objfile->line_buffer. */
const gdb_byte *statement_program_start {}, *statement_program_end {};
+
+ private:
+ /* The include_directories table. Note these are observing
+ pointers. The memory is owned by debug_line_buffer. */
+ std::vector<const char *> m_include_dirs;
+
+ /* The file_names table. This is private because the meaning of indexes
+ differs among DWARF versions (The first valid index is 1 in DWARF 4 and
+ before, and is 0 in DWARF 5 and later). So the client should use
+ file_name_at method for access. */
+ std::vector<file_entry> m_file_names;
};
typedef std::unique_ptr<line_header> line_header_up;
@@ -3644,7 +3663,6 @@ dw2_get_file_names_reader (const struct die_reader_specs *reader,
struct objfile *objfile = dwarf2_per_objfile->objfile;
struct dwarf2_per_cu_data *lh_cu;
struct attribute *attr;
- int i;
void **slot;
struct quick_file_names *qfn;
@@ -3703,12 +3721,12 @@ dw2_get_file_names_reader (const struct die_reader_specs *reader,
if (strcmp (fnd.name, "<unknown>") != 0)
++offset;
- qfn->num_file_names = offset + lh->file_names.size ();
+ qfn->num_file_names = offset + lh->file_names_size ();
qfn->file_names =
XOBNEWVEC (&objfile->objfile_obstack, const char *, qfn->num_file_names);
if (offset != 0)
qfn->file_names[0] = xstrdup (fnd.name);
- for (i = 0; i < lh->file_names.size (); ++i)
+ for (int i = 0; i < lh->file_names_size (); ++i)
qfn->file_names[i + offset] = file_full_name (i + 1, lh.get (), fnd.comp_dir);
qfn->real_names = NULL;
@@ -11717,14 +11735,14 @@ dwarf2_cu::setup_type_unit_groups (struct die_info *die)
process_full_type_unit still needs to know if this is the first
time. */
- tu_group->num_symtabs = line_header->file_names.size ();
+ tu_group->num_symtabs = line_header->file_names_size ();
tu_group->symtabs = XNEWVEC (struct symtab *,
- line_header->file_names.size ());
+ line_header->file_names_size ());
- for (i = 0; i < line_header->file_names.size (); ++i)
+ auto &file_names = line_header->file_names ();
+ for (i = 0; i < file_names.size (); ++i)
{
- file_entry &fe = line_header->file_names[i];
-
+ file_entry &fe = file_names[i];
dwarf2_start_subfile (this, fe.name,
fe.include_dir (line_header));
buildsym_compunit *b = get_builder ();
@@ -11753,10 +11771,10 @@ dwarf2_cu::setup_type_unit_groups (struct die_info *die)
compunit_language (cust),
0, cust));
- for (i = 0; i < line_header->file_names.size (); ++i)
+ auto &file_names = line_header->file_names ();
+ for (i = 0; i < file_names.size (); ++i)
{
- file_entry &fe = line_header->file_names[i];
-
+ file_entry &fe = file_names[i];
fe.symtab = tu_group->symtabs[i];
}
}
@@ -16230,7 +16248,7 @@ process_structure_scope (struct die_info *die, struct dwarf2_cu *cu)
{
/* Any related symtab will do. */
symtab
- = cu->line_header->file_name_at (file_name_index (1))->symtab;
+ = cu->line_header->file_names ()[0].symtab;
}
else
{
@@ -20285,10 +20303,16 @@ void
line_header::add_include_dir (const char *include_dir)
{
if (dwarf_line_debug >= 2)
- fprintf_unfiltered (gdb_stdlog, "Adding dir %zu: %s\n",
- include_dirs.size () + 1, include_dir);
-
- include_dirs.push_back (include_dir);
+ {
+ size_t new_size;
+ if (version >= 5)
+ new_size = m_include_dirs.size ();
+ else
+ new_size = m_include_dirs.size () + 1;
+ fprintf_unfiltered (gdb_stdlog, "Adding dir %zu: %s\n",
+ new_size, include_dir);
+ }
+ m_include_dirs.push_back (include_dir);
}
void
@@ -20298,10 +20322,16 @@ line_header::add_file_name (const char *name,
unsigned int length)
{
if (dwarf_line_debug >= 2)
- fprintf_unfiltered (gdb_stdlog, "Adding file %u: %s\n",
- (unsigned) file_names.size () + 1, name);
-
- file_names.emplace_back (name, d_index, mod_time, length);
+ {
+ size_t new_size;
+ if (version >= 5)
+ new_size = file_names_size ();
+ else
+ new_size = file_names_size () + 1;
+ fprintf_unfiltered (gdb_stdlog, "Adding file %zu: %s\n",
+ new_size, name);
+ }
+ m_file_names.emplace_back (name, d_index, mod_time, length);
}
/* A convenience function to find the proper .debug_line section for a CU. */
@@ -20415,6 +20445,11 @@ read_formatted_entries (struct dwarf2_per_objfile *dwarf2_per_objfile,
buf += 8;
break;
+ case DW_FORM_data16:
+ /* This is used for MD5, but file_entry does not record MD5s. */
+ buf += 16;
+ break;
+
case DW_FORM_udata:
uint.emplace (read_unsigned_leb128 (abfd, buf, &bytes_read));
buf += bytes_read;
@@ -20515,12 +20550,15 @@ dwarf_decode_line_header (sect_offset sect_off, struct dwarf2_cu *cu)
read_checked_initial_length_and_offset (abfd, line_ptr, &cu->header,
&bytes_read, &offset_size);
line_ptr += bytes_read;
+
+ const gdb_byte *start_here = line_ptr;
+
if (line_ptr + lh->total_length > (section->buffer + section->size))
{
dwarf2_statement_list_fits_in_line_number_section_complaint ();
return 0;
}
- lh->statement_program_end = line_ptr + lh->total_length;
+ lh->statement_program_end = start_here + lh->total_length;
lh->version = read_2_bytes (abfd, line_ptr);
line_ptr += 2;
if (lh->version > 5)
@@ -20550,6 +20588,7 @@ dwarf_decode_line_header (sect_offset sect_off, struct dwarf2_cu *cu)
}
lh->header_length = read_offset_1 (abfd, line_ptr, offset_size);
line_ptr += offset_size;
+ lh->statement_program_start = line_ptr + lh->header_length;
lh->minimum_instruction_length = read_1_byte (abfd, line_ptr);
line_ptr += 1;
if (lh->version >= 4)
@@ -20634,7 +20673,6 @@ dwarf_decode_line_header (sect_offset sect_off, struct dwarf2_cu *cu)
}
line_ptr += bytes_read;
}
- lh->statement_program_start = line_ptr;
if (line_ptr > (section->buffer + section->size))
complaint (_("line number info header doesn't "
@@ -20651,12 +20689,11 @@ dwarf_decode_line_header (sect_offset sect_off, struct dwarf2_cu *cu)
Returns NULL if FILE_INDEX should be ignored, i.e., it is pst->filename. */
static const char *
-psymtab_include_file_name (const struct line_header *lh, int file_index,
+psymtab_include_file_name (const struct line_header *lh, const file_entry &fe,
const struct partial_symtab *pst,
const char *comp_dir,
gdb::unique_xmalloc_ptr<char> *name_holder)
{
- const file_entry &fe = lh->file_names[file_index];
const char *include_name = fe.name;
const char *include_name_to_compare = include_name;
const char *pst_filename;
@@ -20831,8 +20868,8 @@ private:
and initialized according to the DWARF spec. */
unsigned char m_op_index = 0;
- /* The line table index (1-based) of the current file. */
- file_name_index m_file = (file_name_index) 1;
+ /* The line table index of the current file. */
+ file_name_index m_file = 1;
unsigned int m_line = 1;
/* These are initialized in the constructor. */
@@ -21024,7 +21061,7 @@ lnp_state_machine::record_line (bool end_sequence)
fprintf_unfiltered (gdb_stdlog,
"Processing actual line %u: file %u,"
" address %s, is_stmt %u, discrim %u\n",
- m_line, to_underlying (m_file),
+ m_line, m_file,
paddress (m_gdbarch, m_address),
m_is_stmt, m_discriminator);
}
@@ -21363,17 +21400,15 @@ dwarf_decode_lines (struct line_header *lh, const char *comp_dir,
if (decode_for_pst_p)
{
- int file_index;
-
/* Now that we're done scanning the Line Header Program, we can
create the psymtab of each included file. */
- for (file_index = 0; file_index < lh->file_names.size (); file_index++)
- if (lh->file_names[file_index].included_p == 1)
+ for (auto &file_entry : lh->file_names ())
+ if (file_entry.included_p == 1)
{
gdb::unique_xmalloc_ptr<char> name_holder;
const char *include_name =
- psymtab_include_file_name (lh, file_index, pst, comp_dir,
- &name_holder);
+ psymtab_include_file_name (lh, file_entry, pst,
+ comp_dir, &name_holder);
if (include_name != NULL)
dwarf2_create_include_psymtab (include_name, pst, objfile);
}
@@ -21385,14 +21420,10 @@ dwarf_decode_lines (struct line_header *lh, const char *comp_dir,
line numbers). */
buildsym_compunit *builder = cu->get_builder ();
struct compunit_symtab *cust = builder->get_compunit_symtab ();
- int i;
- for (i = 0; i < lh->file_names.size (); i++)
+ for (auto &fe : lh->file_names ())
{
- file_entry &fe = lh->file_names[i];
-
dwarf2_start_subfile (cu, fe.name, fe.include_dir (lh));
-
if (builder->get_current_subfile ()->symtab == NULL)
{
builder->get_current_subfile ()->symtab
@@ -24190,6 +24221,14 @@ dwarf_alloc_die (struct dwarf2_cu *cu, int num_attrs)
/* Macro support. */
+static bool
+is_valid_file_index (int file_index, struct line_header *lh)
+{
+ if (lh->version >= 5)
+ return 0 <= file_index && file_index < lh->file_names_size ();
+ return 1 <= file_index && file_index <= lh->file_names_size ();
+}
+
/* Return file name relative to the compilation directory of file number I in
*LH's file name table. The result is allocated using xmalloc; the caller is
responsible for freeing it. */
@@ -24199,17 +24238,17 @@ file_file_name (int file, struct line_header *lh)
{
/* Is the file number a valid index into the line header's file name
table? Remember that file numbers start with one, not zero. */
- if (1 <= file && file <= lh->file_names.size ())
+ if (is_valid_file_index (file, lh))
{
- const file_entry &fe = lh->file_names[file - 1];
+ const file_entry *fe = lh->file_name_at (file);
- if (!IS_ABSOLUTE_PATH (fe.name))
+ if (!IS_ABSOLUTE_PATH (fe->name))
{
- const char *dir = fe.include_dir (lh);
+ const char *dir = fe->include_dir (lh);
if (dir != NULL)
- return concat (dir, SLASH_STRING, fe.name, (char *) NULL);
+ return concat (dir, SLASH_STRING, fe->name, (char *) NULL);
}
- return xstrdup (fe.name);
+ return xstrdup (fe->name);
}
else
{
@@ -24237,7 +24276,7 @@ file_full_name (int file, struct line_header *lh, const char *comp_dir)
{
/* Is the file number a valid index into the line header's file name
table? Remember that file numbers start with one, not zero. */
- if (1 <= file && file <= lh->file_names.size ())
+ if (is_valid_file_index (file, lh))
{
char *relative = file_file_name (file, lh);