From: Tom Tromey <tom@tromey.com>
To: gdb-patches@sourceware.org
Subject: [PATCH v4 02/19] Pre-read DWZ section data
Date: Sun, 10 Dec 2023 14:41:10 -0700 [thread overview]
Message-ID: <20231210-t-bg-dwarf-reading-v4-2-b978c32fd12f@tromey.com> (raw)
In-Reply-To: <20231210-t-bg-dwarf-reading-v4-0-b978c32fd12f@tromey.com>
This changes the DWZ code to pre-read the section data and somewhat
simplify the DWZ API. This makes it easier to add the bfd_cache_close
call to the new dwarf2_read_dwz_file function -- after this is done,
there shouldn't be a reason to keep the BFD's file descriptor open.
---
gdb/dwarf2/dwz.c | 90 ++++++++++++++++++++-----------------------
gdb/dwarf2/dwz.h | 13 +++++--
gdb/dwarf2/macro.c | 2 -
gdb/dwarf2/read-debug-names.c | 2 +-
gdb/dwarf2/read.c | 13 +------
gdb/dwarf2/read.h | 3 +-
6 files changed, 56 insertions(+), 67 deletions(-)
diff --git a/gdb/dwarf2/dwz.c b/gdb/dwarf2/dwz.c
index edd5b56d778..13f95801ebb 100644
--- a/gdb/dwarf2/dwz.c
+++ b/gdb/dwarf2/dwz.c
@@ -53,49 +53,35 @@ dwz_file::read_string (struct objfile *objfile, LONGEST str_offset)
/* A helper function to find the sections for a .dwz file. */
static void
-locate_dwz_sections (bfd *abfd, asection *sectp, dwz_file *dwz_file)
+locate_dwz_sections (struct objfile *objfile, bfd *abfd, asection *sectp,
+ dwz_file *dwz_file)
{
+ dwarf2_section_info *sect = nullptr;
+
/* Note that we only support the standard ELF names, because .dwz
is ELF-only (at the time of writing). */
if (dwarf2_elf_names.abbrev.matches (sectp->name))
- {
- dwz_file->abbrev.s.section = sectp;
- dwz_file->abbrev.size = bfd_section_size (sectp);
- }
+ sect = &dwz_file->abbrev;
else if (dwarf2_elf_names.info.matches (sectp->name))
- {
- dwz_file->info.s.section = sectp;
- dwz_file->info.size = bfd_section_size (sectp);
- }
+ sect = &dwz_file->info;
else if (dwarf2_elf_names.str.matches (sectp->name))
- {
- dwz_file->str.s.section = sectp;
- dwz_file->str.size = bfd_section_size (sectp);
- }
+ sect = &dwz_file->str;
else if (dwarf2_elf_names.line.matches (sectp->name))
- {
- dwz_file->line.s.section = sectp;
- dwz_file->line.size = bfd_section_size (sectp);
- }
+ sect = &dwz_file->line;
else if (dwarf2_elf_names.macro.matches (sectp->name))
- {
- dwz_file->macro.s.section = sectp;
- dwz_file->macro.size = bfd_section_size (sectp);
- }
+ sect = &dwz_file->macro;
else if (dwarf2_elf_names.gdb_index.matches (sectp->name))
- {
- dwz_file->gdb_index.s.section = sectp;
- dwz_file->gdb_index.size = bfd_section_size (sectp);
- }
+ sect = &dwz_file->gdb_index;
else if (dwarf2_elf_names.debug_names.matches (sectp->name))
- {
- dwz_file->debug_names.s.section = sectp;
- dwz_file->debug_names.size = bfd_section_size (sectp);
- }
+ sect = &dwz_file->debug_names;
else if (dwarf2_elf_names.types.matches (sectp->name))
+ sect = &dwz_file->types;
+
+ if (sect != nullptr)
{
- dwz_file->types.s.section = sectp;
- dwz_file->types.size = bfd_section_size (sectp);
+ sect->s.section = sectp;
+ sect->size = bfd_section_size (sectp);
+ sect->read (objfile);
}
}
@@ -190,20 +176,13 @@ dwz_search_other_debugdirs (std::string &filename, bfd_byte *buildid,
/* See dwz.h. */
-struct dwz_file *
-dwarf2_get_dwz_file (dwarf2_per_bfd *per_bfd, bool require)
+void
+dwarf2_read_dwz_file (dwarf2_per_objfile *per_objfile)
{
bfd_size_type buildid_len_arg;
size_t buildid_len;
bfd_byte *buildid;
-
- if (per_bfd->dwz_file.has_value ())
- {
- dwz_file *result = per_bfd->dwz_file->get ();
- if (require && result == nullptr)
- error (_("could not read '.gnu_debugaltlink' section"));
- return result;
- }
+ dwarf2_per_bfd *per_bfd = per_objfile->per_bfd;
/* This may query the user via the debuginfod support, so it may
only be run in the main thread. */
@@ -219,11 +198,7 @@ dwarf2_get_dwz_file (dwarf2_per_bfd *per_bfd, bool require)
if (data == NULL)
{
if (bfd_get_error () == bfd_error_no_error)
- {
- if (!require)
- return nullptr;
- error (_("could not read '.gnu_debugaltlink' section"));
- }
+ return;
error (_("could not read '.gnu_debugaltlink' section: %s"),
bfd_errmsg (bfd_get_error ()));
}
@@ -292,9 +267,28 @@ dwarf2_get_dwz_file (dwarf2_per_bfd *per_bfd, bool require)
(new struct dwz_file (std::move (dwz_bfd)));
for (asection *sec : gdb_bfd_sections (result->dwz_bfd))
- locate_dwz_sections (result->dwz_bfd.get (), sec, result.get ());
+ locate_dwz_sections (per_objfile->objfile, result->dwz_bfd.get (),
+ sec, result.get ());
gdb_bfd_record_inclusion (per_bfd->obfd, result->dwz_bfd.get ());
+ bfd_cache_close (result->dwz_bfd.get ());
+
per_bfd->dwz_file = std::move (result);
- return per_bfd->dwz_file->get ();
+}
+
+/* See dwz.h. */
+
+struct dwz_file *
+dwarf2_get_dwz_file (dwarf2_per_bfd *per_bfd, bool require)
+{
+ gdb_assert (!require || per_bfd->dwz_file.has_value ());
+
+ dwz_file *result = nullptr;
+ if (per_bfd->dwz_file.has_value ())
+ {
+ result = per_bfd->dwz_file->get ();
+ if (require && result == nullptr)
+ error (_("could not read '.gnu_debugaltlink' section"));
+ }
+ return result;
}
diff --git a/gdb/dwarf2/dwz.h b/gdb/dwarf2/dwz.h
index 5f61b5e1216..a427cda902d 100644
--- a/gdb/dwarf2/dwz.h
+++ b/gdb/dwarf2/dwz.h
@@ -65,13 +65,20 @@ struct dwz_file
const char *read_string (struct objfile *objfile, LONGEST str_offset);
};
-/* Open the separate '.dwz' debug file, if needed. If there is no
+/* Return the separate '.dwz' debug file. If there is no
.gnu_debugaltlink section in the file, then the result depends on
REQUIRE: if REQUIRE is true, then error; if REQUIRE is false,
- return NULL. Always error if there is such a section but the file
- cannot be found. */
+ return NULL. */
extern dwz_file *dwarf2_get_dwz_file (dwarf2_per_bfd *per_bfd,
bool require = false);
+/* Open the separate '.dwz' debug file, if needed. This just sets the
+ appropriate field in the per-BFD structure. If the DWZ file
+ exists, the relevant sections are read in as well. Throws an error
+ if the .gnu_debugaltlink section exists but the file cannot be
+ found. */
+
+extern void dwarf2_read_dwz_file (dwarf2_per_objfile *per_objfile);
+
#endif /* GDB_DWARF2_DWZ_H */
diff --git a/gdb/dwarf2/macro.c b/gdb/dwarf2/macro.c
index 7d86d16d0e3..2ee9f8c1009 100644
--- a/gdb/dwarf2/macro.c
+++ b/gdb/dwarf2/macro.c
@@ -735,8 +735,6 @@ dwarf_decode_macro_bytes (dwarf2_per_objfile *per_objfile,
dwz_file *dwz = dwarf2_get_dwz_file (per_objfile->per_bfd,
true);
- dwz->macro.read (objfile);
-
include_section = &dwz->macro;
include_bfd = include_section->get_bfd_owner ();
include_mac_end = dwz->macro.buffer + dwz->macro.size;
diff --git a/gdb/dwarf2/read-debug-names.c b/gdb/dwarf2/read-debug-names.c
index 59c49da5553..e912c2a1114 100644
--- a/gdb/dwarf2/read-debug-names.c
+++ b/gdb/dwarf2/read-debug-names.c
@@ -467,7 +467,7 @@ dwarf2_read_debug_names (dwarf2_per_objfile *per_objfile)
}
}
- create_all_units (per_objfile, false);
+ create_all_units (per_objfile);
if (!check_cus_from_debug_names (per_bfd, *map, dwz_map))
{
per_bfd->all_units.clear ();
diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
index 9a5f52d0f7e..9fd61eb0777 100644
--- a/gdb/dwarf2/read.c
+++ b/gdb/dwarf2/read.c
@@ -3201,7 +3201,7 @@ dwarf2_initialize_objfile (struct objfile *objfile)
main thread. */
try
{
- dwarf2_get_dwz_file (per_bfd);
+ dwarf2_read_dwz_file (per_objfile);
}
catch (const gdb_exception_error &err)
{
@@ -5101,7 +5101,7 @@ finalize_all_units (dwarf2_per_bfd *per_bfd)
/* See read.h. */
void
-create_all_units (dwarf2_per_objfile *per_objfile, bool pre_read_p)
+create_all_units (dwarf2_per_objfile *per_objfile)
{
htab_up types_htab;
gdb_assert (per_objfile->per_bfd->all_units.empty ());
@@ -5117,15 +5117,6 @@ create_all_units (dwarf2_per_objfile *per_objfile, bool pre_read_p)
dwz_file *dwz = dwarf2_get_dwz_file (per_objfile->per_bfd);
if (dwz != NULL)
{
- if (pre_read_p)
- {
- /* Pre-read the sections we'll need to construct an index. */
- struct objfile *objfile = per_objfile->objfile;
- dwz->abbrev.read (objfile);
- dwz->info.read (objfile);
- dwz->str.read (objfile);
- dwz->line.read (objfile);
- }
read_comp_units_from_section (per_objfile, &dwz->info, &dwz->abbrev, 1,
types_htab, rcuh_kind::COMPILE);
diff --git a/gdb/dwarf2/read.h b/gdb/dwarf2/read.h
index 6f97f641c8e..4ab869cdd29 100644
--- a/gdb/dwarf2/read.h
+++ b/gdb/dwarf2/read.h
@@ -966,8 +966,7 @@ extern void finalize_all_units (dwarf2_per_bfd *per_bfd);
/* Create a list of all compilation units in OBJFILE. */
-extern void create_all_units (dwarf2_per_objfile *per_objfile,
- bool pre_read_p = true);
+extern void create_all_units (dwarf2_per_objfile *per_objfile);
/* Create a quick_file_names hash table. */
--
2.43.0
next prev parent reply other threads:[~2023-12-10 21:41 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-12-10 21:41 [PATCH v4 00/19] Index DWARF in the background Tom Tromey
2023-12-10 21:41 ` [PATCH v4 01/19] Don't use objfile::intern in DWO code Tom Tromey
2024-01-09 18:44 ` Simon Marchi
2024-01-09 19:12 ` Tom Tromey
2024-01-09 19:51 ` Tom Tromey
2023-12-10 21:41 ` Tom Tromey [this message]
2023-12-10 21:41 ` [PATCH v4 03/19] Add a couple of bfd_cache_close calls Tom Tromey
2023-12-10 21:41 ` [PATCH v4 04/19] Add thread-safety to gdb's BFD wrappers Tom Tromey
2023-12-10 21:41 ` [PATCH v4 05/19] Refactor complaint thread-safety approach Tom Tromey
2023-12-10 21:41 ` [PATCH v4 06/19] Add deferred_warnings parameter to read_addrmap_from_aranges Tom Tromey
2023-12-10 21:41 ` [PATCH v4 07/19] Add quick_symbol_functions::compute_main_name Tom Tromey
2023-12-10 21:41 ` [PATCH v4 08/19] Add gdb::task_group Tom Tromey
2023-12-18 14:55 ` Tom Tromey
2023-12-10 21:41 ` [PATCH v4 09/19] Move cooked_index_storage to cooked-index.h Tom Tromey
2023-12-10 21:41 ` [PATCH v4 10/19] Add "maint set dwarf synchronous" Tom Tromey
2023-12-10 21:41 ` [PATCH v4 11/19] Change how cooked index waits for threads Tom Tromey
2023-12-10 21:41 ` [PATCH v4 12/19] Do more DWARF reading in the background Tom Tromey
2023-12-10 21:41 ` [PATCH v4 13/19] Simplify the public DWARF API Tom Tromey
2023-12-10 21:41 ` [PATCH v4 14/19] Remove two quick_symbol_functions methods Tom Tromey
2023-12-10 21:41 ` [PATCH v4 15/19] Change current_language to be a macro Tom Tromey
2023-12-10 21:41 ` [PATCH v4 16/19] Lazy language setting Tom Tromey
2023-12-10 21:41 ` [PATCH v4 17/19] Optimize lookup_minimal_symbol_text Tom Tromey
2023-12-10 21:41 ` [PATCH v4 18/19] Avoid language-based lookups in startup path Tom Tromey
2023-12-10 21:41 ` [PATCH v4 19/19] Back out some parallel_for_each features Tom Tromey
2024-01-09 1:08 ` [PATCH v4 00/19] Index DWARF in the background Tom Tromey
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