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[RFA] Add support for pretty-printing .gdb_index section
- From: dje at google dot com (Doug Evans)
- To: binutils at sourceware dot org
- Cc: tromey at redhat dot com
- Date: Thu, 2 Dec 2010 16:53:07 -0800 (PST)
- Subject: [RFA] Add support for pretty-printing .gdb_index section
Hi.
.gdb_index is a section that can be created by gdb (and merged
into an executable by objcopy) that can greatly speed up
gdb start up. See gdb/dwarf2.c:save_gdb_index_command for a
description of its contents.
This patch adds a pretty-printer, which is useful when debugging
problems with it.
Ok to check in?
[I don't know what the rules are regarding stdint.h.
Let me know if/how you need it changed.]
2010-12-02 Doug Evans <dje@google.com>
* dwarf.c: #include "bfd_stdint.h".
(do_gdb_index): New global.
(display_gdb_index): New function.
(dwarf_select_sections_by_names) Add "gdb_index".
(dwarf_select_sections_all): Set do_gdb_index.
(debug_displays): Add .gdb_index.
* dwarf.h (do_gdb_index): Declare.
* readelf.c (process_section_headers): Process ".gdb_index".
* doc/binutils.texi (readelf): Document gdb_index dump.
(objdump): Ditto.
Index: dwarf.c
===================================================================
RCS file: /cvs/src/src/binutils/dwarf.c,v
retrieving revision 1.80
diff -u -p -r1.80 dwarf.c
--- dwarf.c 26 Nov 2010 05:35:01 -0000 1.80
+++ dwarf.c 3 Dec 2010 00:40:09 -0000
@@ -22,6 +22,7 @@
#include "sysdep.h"
#include "libiberty.h"
#include "bfd.h"
+#include "bfd_stdint.h"
#include "bucomm.h"
#include "elfcomm.h"
#include "elf/common.h"
@@ -56,6 +57,7 @@ int do_debug_frames_interp;
int do_debug_macinfo;
int do_debug_str;
int do_debug_loc;
+int do_gdb_index;
int do_trace_info;
int do_trace_abbrevs;
int do_trace_aranges;
@@ -4863,6 +4865,135 @@ display_debug_frames (struct dwarf_secti
#undef SLEB
static int
+display_gdb_index (struct dwarf_section *section,
+ void *file ATTRIBUTE_UNUSED)
+{
+ unsigned char *start = section->start;
+ uint32_t version;
+ uint32_t cu_list_offset, tu_list_offset;
+ uint32_t address_table_offset, symbol_table_offset, constant_pool_offset;
+ unsigned int cu_list_elements, tu_list_elements;
+ unsigned int address_table_size, symbol_table_slots;
+ unsigned char *cu_list, *tu_list;
+ unsigned char *address_table, *symbol_table, *constant_pool;
+ unsigned int i;
+
+ /* The documentation for the format of this file is in gdb/dwarf2read.c. */
+
+ printf (_("Contents of the %s section:\n"), section->name);
+
+ if (section->size < 6 * sizeof (uint32_t))
+ {
+ warn (_("Truncated header in the %s section.\n"), section->name);
+ return 0;
+ }
+
+ version = byte_get_little_endian (start, 4);
+ printf (_("Version %d\n"), version);
+
+ /* Prior versions are obsolete, and future versions may not be
+ backwards compatible. */
+ if (version != 3)
+ {
+ warn (_("Unsupported version %u.\n"), version);
+ return 0;
+ }
+
+ cu_list_offset = byte_get_little_endian (start + 4, 4);
+ tu_list_offset = byte_get_little_endian (start + 8, 4);
+ address_table_offset = byte_get_little_endian (start + 12, 4);
+ symbol_table_offset = byte_get_little_endian (start + 16, 4);
+ constant_pool_offset = byte_get_little_endian (start + 20, 4);
+
+ if (cu_list_offset > section->size
+ || tu_list_offset > section->size
+ || address_table_offset > section->size
+ || symbol_table_offset > section->size
+ || constant_pool_offset > section->size)
+ {
+ warn (_("Corrupt header in the %s section.\n"), section->name);
+ return 0;
+ }
+
+ cu_list_elements = (tu_list_offset - cu_list_offset) / 8;
+ tu_list_elements = (address_table_offset - tu_list_offset) / 8;
+ address_table_size = symbol_table_offset - address_table_offset;
+ symbol_table_slots = (constant_pool_offset - symbol_table_offset) / 8;
+
+ cu_list = start + cu_list_offset;
+ tu_list = start + tu_list_offset;
+ address_table = start + address_table_offset;
+ symbol_table = start + symbol_table_offset;
+ constant_pool = start + constant_pool_offset;
+
+ printf (_("\nCU table:\n"));
+ for (i = 0; i < cu_list_elements; i += 2)
+ {
+ uint64_t cu_offset = byte_get_little_endian (cu_list + i * 8, 8);
+ uint64_t cu_length = byte_get_little_endian (cu_list + i * 8 + 8, 8);
+
+ printf (_("[%3u] 0x%lx - 0x%lx\n"), i / 2,
+ (unsigned long) cu_offset,
+ (unsigned long) (cu_offset + cu_length - 1));
+ }
+
+ printf (_("\nTU table:\n"));
+ for (i = 0; i < tu_list_elements; i += 3)
+ {
+ uint64_t tu_offset = byte_get_little_endian (tu_list + i * 8, 8);
+ uint64_t type_offset = byte_get_little_endian (tu_list + i * 8 + 8, 8);
+ uint64_t signature = byte_get_little_endian (tu_list + i * 8 + 16, 8);
+
+ printf (_("[%3u] 0x%lx 0x%lx "), i / 3,
+ (unsigned long) tu_offset,
+ (unsigned long) type_offset);
+ print_dwarf_vma (signature, 8);
+ printf ("\n");
+ }
+
+ printf (_("\nAddress table:\n"));
+ for (i = 0; i < address_table_size; i += 2 * 8 + 4)
+ {
+ uint64_t low = byte_get_little_endian (address_table + i, 8);
+ uint64_t high = byte_get_little_endian (address_table + i + 8, 8);
+ uint32_t cu_index = byte_get_little_endian (address_table + i + 16, 4);
+
+ print_dwarf_vma (low, 8);
+ print_dwarf_vma (high, 8);
+ printf (_("%u\n"), cu_index);
+ }
+
+ printf (_("\nSymbol table:\n"));
+ for (i = 0; i < symbol_table_slots; ++i)
+ {
+ uint32_t name_offset = byte_get_little_endian (symbol_table + i * 8, 4);
+ uint32_t cu_vector_offset = byte_get_little_endian (symbol_table + i * 8 + 4, 4);
+ uint32_t num_cus, cu;
+
+ if (name_offset != 0
+ || cu_vector_offset != 0)
+ {
+ unsigned int j;
+
+ printf ("[%3u] %s:", i, constant_pool + name_offset);
+ num_cus = byte_get_little_endian (constant_pool + cu_vector_offset, 4);
+ for (j = 0; j < num_cus; ++j)
+ {
+ cu = byte_get_little_endian (constant_pool + cu_vector_offset + 4 + j * 4, 4);
+ /* Convert to TU number if it's for a type unit. */
+ if (cu >= cu_list_elements)
+ printf (" T%u", cu - cu_list_elements);
+ else
+ printf (" %u", cu);
+ }
+ printf ("\n");
+ }
+ }
+
+ return 1;
+}
+
+static int
display_debug_not_supported (struct dwarf_section *section,
void *file ATTRIBUTE_UNUSED)
{
@@ -4965,6 +5096,8 @@ dwarf_select_sections_by_names (const ch
with earlier versions of readelf. */
{ "ranges", & do_debug_aranges, 1 },
{ "str", & do_debug_str, 1 },
+ /* The special .gdb_index section. */
+ { "gdb_index", & do_gdb_index, 1 },
/* These trace_* sections are used by Itanium VMS. */
{ "trace_abbrev", & do_trace_abbrevs, 1 },
{ "trace_aranges", & do_trace_aranges, 1 },
@@ -5089,6 +5222,7 @@ dwarf_select_sections_all (void)
do_debug_macinfo = 1;
do_debug_str = 1;
do_debug_loc = 1;
+ do_gdb_index = 1;
do_trace_info = 1;
do_trace_abbrevs = 1;
do_trace_aranges = 1;
@@ -5128,6 +5262,8 @@ struct dwarf_section_display debug_displ
display_debug_types, &do_debug_info, 1 },
{ { ".debug_weaknames", ".zdebug_weaknames", NULL, NULL, 0, 0 },
display_debug_not_supported, NULL, 0 },
+ { { ".gdb_index", "", NULL, NULL, 0, 0 },
+ display_gdb_index, &do_gdb_index, 0 },
{ { ".trace_info", "", NULL, NULL, 0, 0 },
display_trace_info, &do_trace_info, 1 },
{ { ".trace_abbrev", "", NULL, NULL, 0, 0 },
Index: dwarf.h
===================================================================
RCS file: /cvs/src/src/binutils/dwarf.h,v
retrieving revision 1.19
diff -u -p -r1.19 dwarf.h
--- dwarf.h 21 Nov 2010 21:27:15 -0000 1.19
+++ dwarf.h 3 Dec 2010 00:40:09 -0000
@@ -107,6 +107,7 @@ extern int do_debug_frames_interp;
extern int do_debug_macinfo;
extern int do_debug_str;
extern int do_debug_loc;
+extern int do_gdb_index;
extern int do_trace_info;
extern int do_trace_abbrevs;
extern int do_trace_aranges;
Index: readelf.c
===================================================================
RCS file: /cvs/src/src/binutils/readelf.c,v
retrieving revision 1.527
diff -u -p -r1.527 readelf.c
--- readelf.c 21 Nov 2010 21:27:15 -0000 1.527
+++ readelf.c 3 Dec 2010 00:40:09 -0000
@@ -4564,6 +4564,8 @@ process_section_headers (FILE * file)
request_dump_bynumber (i, DEBUG_DUMP);
else if (do_debug_frames && streq (name, ".eh_frame"))
request_dump_bynumber (i, DEBUG_DUMP);
+ else if (do_gdb_index && streq (name, ".gdb_index"))
+ request_dump_bynumber (i, DEBUG_DUMP);
/* Trace sections for Itanium VMS. */
else if ((do_debugging || do_trace_info || do_trace_abbrevs
|| do_trace_aranges)
Index: doc/binutils.texi
===================================================================
RCS file: /cvs/src/src/binutils/doc/binutils.texi,v
retrieving revision 1.173
diff -u -p -r1.173 binutils.texi
--- doc/binutils.texi 29 Oct 2010 12:10:32 -0000 1.173
+++ doc/binutils.texi 3 Dec 2010 00:40:09 -0000
@@ -1746,7 +1746,7 @@ objdump [@option{-a}|@option{--archive-h
[@option{-R}|@option{--dynamic-reloc}]
[@option{-s}|@option{--full-contents}]
[@option{-W[lLiaprmfFsoRt]}|
- @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges]]
+ @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index]]
[@option{-G}|@option{--stabs}]
[@option{-t}|@option{--syms}]
[@option{-T}|@option{--dynamic-syms}]
@@ -2119,7 +2119,7 @@ Display @var{width} bytes on a single li
instructions.
@item -W[lLiaprmfFsoRt]
-@itemx --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges]
+@itemx --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index]
@cindex DWARF
@cindex debug symbols
Displays the contents of the debug sections in the file, if any are
@@ -2127,7 +2127,7 @@ present. If one of the optional letters
then only data found in those specific sections will be dumped.
Note that there is no single letter option to display the content of
-trace sections.
+trace sections or .gdb_index.
@item -G
@itemx --stabs
@@ -3949,7 +3949,7 @@ readelf [@option{-a}|@option{--all}]
[@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
[@option{-c}|@option{--archive-index}]
[@option{-w[lLiaprmfFsoRt]}|
- @option{--debug-dump}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges]]
+ @option{--debug-dump}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index]]
[@option{-I}|@option{--histogram}]
[@option{-v}|@option{--version}]
[@option{-W}|@option{--wide}]
@@ -4101,13 +4101,13 @@ of binary archives. Performs the same f
command to @command{ar}, but without using the BFD library. @xref{ar}.
@item -w[lLiaprmfFsoRt]
-@itemx --debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges]
+@itemx --debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index]
Displays the contents of the debug sections in the file, if any are
present. If one of the optional letters or words follows the switch
then only data found in those specific sections will be dumped.
Note that there is no single letter option to display the content of
-trace sections.
+trace sections or .gdb_index.
Note: the @option{=decodedline} option will display the interpreted
contents of a .debug_line section whereas the @option{=rawline} option