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[PATCH 3/4] Increasing support for dwarf 5.
- From: "Ali Tamur via gdb-patches" <gdb-patches at sourceware dot org>
- To: gdb-patches at sourceware dot org
- Cc: Ali Tamur <tamur at google dot com>
- Date: Tue, 27 Aug 2019 16:41:58 -0700
- Subject: [PATCH 3/4] Increasing support for dwarf 5.
- Reply-to: Ali Tamur <tamur at google dot com>
* Line table header has new fields.
* Fix handling of file and directory indexes in line tables; in dwarf 5 the
indexes are zero-based.
gdb/ChangeLog:
2019-08-26 Ali Tamur <tamur@google.com>
* gdb/dwarf2read.c (dir_index): Change definition and update comment.
(file_name_index): Likewise.
(line_header::include_dir_at): Allow for zero based indexes for dwarf 5.
(line_header::file_name_at): Likewise.
(line_header::file_names): Make the field private to abstract the fact
that dwarf 4 and 5 use different index bases.
(line_header::file_names_size): New method to let the clients use
instead of accessing file_names directly.
(line_header::first_file_index): Likewise.
(file_full_name): Add parameter, is_zero_indexed. The file indexes in
the line table is 1-based in dwarf 4, and 0 based in dwarf 5.
(dw2_get_file_names_reader): Initialize variable, use added methods to
access file names in the line table.
(dwarf2_cu::setup_type_unit_groups): Use added methods to access file
and directory names in line table.
(process_structure_scope): Use added methods to access file names at the
line table.
(line_header::add_file_name): Reflect API change.
(dwarf_decode_line_header): Fix statement_program boundry calculations.
(psymtab_include_file_name): Reflect API changes.
(lnp_state_machine::current_file): Likewise.
(lnp_state_machine::record_line): Likewise.
(lnp_state_machine::lnp_state_machine): Initialize m_file.
(dwarf_decode_lines): Reflect API changes.
(new_symbol): Likewise.
(is_valid_file_index): New function.
(file_file_name): Add parameter, is_zero_indexed.
(file_full_name): Likewise.
---
gdb/dwarf2read.c | 161 +++++++++++++++++++++++++++--------------------
1 file changed, 93 insertions(+), 68 deletions(-)
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index b04993e9b6..73ec371af1 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -919,13 +919,13 @@ 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 dwarf5 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 dwarf5
+ and later. */
+typedef int file_name_index;
struct file_entry
{
@@ -977,26 +977,30 @@ 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 dwarf5 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;
+ size_t vec_index;
+ if (version <= 4)
+ vec_index = index - 1;
+ else
+ vec_index = index;
if (vec_index >= include_dirs.size ())
return NULL;
return include_dirs[vec_index];
}
- /* Return the file name at INDEX (1-based). Returns NULL if INDEX
- is out of bounds. */
- file_entry *file_name_at (file_name_index index)
+ /* Return the file name at INDEX (0-based in dwarf5 and 1-based before).
+ Returns NULL if INDEX is out of bounds. */
+ file_entry *file_name_at (file_name_index index, bool is_zero_indexed)
{
- /* Convert file name index number (1-based) to vector index
- (0-based). */
- size_t vec_index = to_underlying (index) - 1;
+ size_t vec_index;
+ if (is_zero_indexed || version >= 5)
+ vec_index = index;
+ else
+ vec_index = index - 1;
if (vec_index >= file_names.size ())
return NULL;
@@ -1029,12 +1033,24 @@ 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 file_names.size();
+ }
+
+ int first_file_index() {
+ return version >= 5 ? 0 : 1;
+ }
/* 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 file_names table. This is private because the meaning of indexes differ
+ 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> file_names;
};
typedef std::unique_ptr<line_header> line_header_up;
@@ -1957,7 +1973,7 @@ static file_and_directory find_file_and_directory (struct die_info *die,
struct dwarf2_cu *cu);
static char *file_full_name (int file, struct line_header *lh,
- const char *comp_dir);
+ const char *comp_dir, bool is_zero_indexed);
/* Expected enum dwarf_unit_type for read_comp_unit_head. */
enum class rcuh_kind { COMPILE, TYPE };
@@ -3633,7 +3649,7 @@ 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;
+ int i = 0;
void **slot;
struct quick_file_names *qfn;
@@ -3688,11 +3704,11 @@ dw2_get_file_names_reader (const struct die_reader_specs *reader,
file_and_directory fnd = find_file_and_directory (comp_unit_die, cu);
- qfn->num_file_names = lh->file_names.size ();
+ qfn->num_file_names = lh->file_names_size ();
qfn->file_names =
- XOBNEWVEC (&objfile->objfile_obstack, const char *, lh->file_names.size ());
- for (i = 0; i < lh->file_names.size (); ++i)
- qfn->file_names[i] = file_full_name (i + 1, lh.get (), fnd.comp_dir);
+ XOBNEWVEC (&objfile->objfile_obstack, const char *, lh->file_names_size ());
+ for (i = 0; i < lh->file_names_size (); ++i)
+ qfn->file_names[i] = file_full_name (i, lh.get (), fnd.comp_dir, true);
qfn->real_names = NULL;
lh_cu->v.quick->file_names = qfn;
@@ -11648,16 +11664,16 @@ 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)
+ for (i = 0; i < line_header->file_names_size (); ++i)
{
- file_entry &fe = line_header->file_names[i];
+ file_entry *fe = line_header->file_name_at(i, true);
- dwarf2_start_subfile (this, fe.name,
- fe.include_dir (line_header));
+ dwarf2_start_subfile (this, fe->name,
+ fe->include_dir (line_header));
buildsym_compunit *b = get_builder ();
if (b->get_current_subfile ()->symtab == NULL)
{
@@ -11670,8 +11686,8 @@ dwarf2_cu::setup_type_unit_groups (struct die_info *die)
= allocate_symtab (cust, b->get_current_subfile ()->name);
}
- fe.symtab = b->get_current_subfile ()->symtab;
- tu_group->symtabs[i] = fe.symtab;
+ fe->symtab = b->get_current_subfile ()->symtab;
+ tu_group->symtabs[i] = fe->symtab;
}
}
else
@@ -11684,11 +11700,10 @@ 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)
+ for (i = 0; i < line_header->file_names_size (); ++i)
{
- file_entry &fe = line_header->file_names[i];
-
- fe.symtab = tu_group->symtabs[i];
+ file_entry *fe = line_header->file_name_at(i, true);
+ fe->symtab = tu_group->symtabs[i];
}
}
@@ -16161,7 +16176,7 @@ 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_name_at (0, true)->symtab;
}
else
{
@@ -20224,7 +20239,7 @@ line_header::add_file_name (const char *name,
{
if (dwarf_line_debug >= 2)
fprintf_unfiltered (gdb_stdlog, "Adding file %u: %s\n",
- (unsigned) file_names.size () + 1, name);
+ (unsigned) file_names_size () + 1, name);
file_names.emplace_back (name, d_index, mod_time, length);
}
@@ -20440,12 +20455,15 @@ 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)
@@ -20475,6 +20493,7 @@ 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)
@@ -20559,7 +20578,6 @@ 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 "
@@ -20576,18 +20594,18 @@ 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 (struct line_header *lh, int file_index,
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;
+ file_entry *fe = lh->file_name_at(file_index, true);
+ const char *include_name = fe->name;
const char *include_name_to_compare = include_name;
const char *pst_filename;
int file_is_pst;
- const char *dir_name = fe.include_dir (lh);
+ const char *dir_name = fe->include_dir (lh);
gdb::unique_xmalloc_ptr<char> hold_compare;
if (!IS_ABSOLUTE_PATH (include_name)
@@ -20659,7 +20677,7 @@ public:
{
/* lh->file_names is 0-based, but the file name numbers in the
statement program are 1-based. */
- return m_line_header->file_name_at (m_file);
+ return m_line_header->file_name_at (m_file, false);
}
/* Record the line in the state machine. END_SEQUENCE is true if
@@ -20756,12 +20774,11 @@ 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;
unsigned int m_line = 1;
/* These are initialized in the constructor. */
+ file_name_index m_file;
CORE_ADDR m_address;
bool m_is_stmt;
unsigned int m_discriminator;
@@ -20949,7 +20966,7 @@ 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);
}
@@ -20999,6 +21016,7 @@ lnp_state_machine::lnp_state_machine (struct dwarf2_cu *cu, gdbarch *arch,
m_gdbarch = arch;
m_record_lines_p = record_lines_p;
m_line_header = lh;
+ m_file = m_line_header->first_file_index();
m_currently_recording_lines = true;
@@ -21292,8 +21310,8 @@ dwarf_decode_lines (struct line_header *lh, const char *comp_dir,
/* 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 (file_index = 0; file_index < lh->file_names_size (); file_index++)
+ if (lh->file_name_at(file_index, true)->included_p == 1)
{
gdb::unique_xmalloc_ptr<char> name_holder;
const char *include_name =
@@ -21312,11 +21330,11 @@ dwarf_decode_lines (struct line_header *lh, const char *comp_dir,
struct compunit_symtab *cust = builder->get_compunit_symtab ();
int i;
- for (i = 0; i < lh->file_names.size (); i++)
+ for (i = 0; i < lh->file_names_size (); i++)
{
- file_entry &fe = lh->file_names[i];
+ file_entry *fe = lh->file_name_at(i, true);
- dwarf2_start_subfile (cu, fe.name, fe.include_dir (lh));
+ dwarf2_start_subfile (cu, fe->name, fe->include_dir (lh));
if (builder->get_current_subfile ()->symtab == NULL)
{
@@ -21324,7 +21342,7 @@ dwarf_decode_lines (struct line_header *lh, const char *comp_dir,
= allocate_symtab (cust,
builder->get_current_subfile ()->name);
}
- fe.symtab = builder->get_current_subfile ()->symtab;
+ fe->symtab = builder->get_current_subfile ()->symtab;
}
}
}
@@ -21543,7 +21561,7 @@ new_symbol (struct die_info *die, struct type *type, struct dwarf2_cu *cu,
struct file_entry *fe;
if (cu->line_header != NULL)
- fe = cu->line_header->file_name_at (file_index);
+ fe = cu->line_header->file_name_at (file_index, false);
else
fe = NULL;
@@ -24074,22 +24092,28 @@ dwarf_alloc_die (struct dwarf2_cu *cu, int num_attrs)
*LH's file name table. The result is allocated using xmalloc; the caller is
responsible for freeing it. */
+bool is_valid_file_index(int file_index, struct line_header *lh, bool is_zero_indexed) {
+ if (is_zero_indexed || lh->version >= 5)
+ return 0 <= file_index && file_index < lh->file_names_size ();
+ return 1 <= file_index && file_index <= lh->file_names_size ();
+}
+
static char *
-file_file_name (int file, struct line_header *lh)
+file_file_name (int file, struct line_header *lh, bool is_zero_indexed)
{
/* 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, is_zero_indexed))
{
- const file_entry &fe = lh->file_names[file - 1];
+ const file_entry *fe = lh->file_name_at(file, is_zero_indexed);
- 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
{
@@ -24113,13 +24137,14 @@ file_file_name (int file, struct line_header *lh)
compilation. The result is allocated using xmalloc; the caller is
responsible for freeing it. */
static char *
-file_full_name (int file, struct line_header *lh, const char *comp_dir)
+file_full_name (int file, struct line_header *lh, const char *comp_dir,
+ bool is_zero_indexed)
{
/* 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, is_zero_indexed))
{
- char *relative = file_file_name (file, lh);
+ char *relative = file_file_name (file, lh, is_zero_indexed);
if (IS_ABSOLUTE_PATH (relative) || comp_dir == NULL)
return relative;
@@ -24127,7 +24152,7 @@ file_full_name (int file, struct line_header *lh, const char *comp_dir)
relative, (char *) NULL);
}
else
- return file_file_name (file, lh);
+ return file_file_name (file, lh, is_zero_indexed);
}
@@ -24138,7 +24163,7 @@ macro_start_file (struct dwarf2_cu *cu,
struct line_header *lh)
{
/* File name relative to the compilation directory of this source file. */
- char *file_name = file_file_name (file, lh);
+ char *file_name = file_file_name (file, lh, false);
if (! current_file)
{
--
2.23.0.187.g17f5b7556c-goog