From 45940949265417e8a21b5936e906cf24a3177001 Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Wed, 27 May 2020 11:13:48 -0400 Subject: [PATCH] Introduce dwarf2_per_objfile::obstack Currently much of the DWARF-related data is stored on the objfile obstack. This prevents sharing this data across objfiles, so this patch adds a new obstack to dwarf2_per_objfile. Note that the dwarf2_per_objfile type is going to become "dwarf2_per_bfd" in a subsequent patch, which is indeed going to be shared between objfiles. One way to check whether this is correct is to look at the remaining uses of objfile_obstack in the DWARF code and note that they all appear in the "full CU" code paths. The converse -- storing per-objfile data on the shared obstack -- is not good, but it is just a memory leak, not a potential use-after-free. Double-checking this would also be useful, though. gdb/ChangeLog: * dwarf2/read.h (struct dwarf2_per_objfile) : New member. * dwarf2/read.c (delete_file_name_entry): Fix comment. (create_cu_from_index_list) (create_signatured_type_table_from_index) (create_signatured_type_table_from_debug_names) (dw2_get_file_names_reader, dwarf2_initialize_objfile) (dwarf2_create_include_psymtab) (create_debug_type_hash_table, add_type_unit) (create_type_unit_group, read_comp_units_from_section) (dwarf2_compute_name, create_cus_hash_table) (create_dwp_hash_table, create_dwo_unit_in_dwp_v1) (create_dwo_unit_in_dwp_v2, open_and_init_dwp_file): Use new obstack. (dw2_get_real_path): Likewise. Change argument to dwarf2_per_objfile. Change-Id: Icdec7be7c4d9f33d1dce4f807284f3077f7d3f03 --- gdb/ChangeLog | 19 ++++++++++ gdb/dwarf2/read.c | 94 +++++++++++++++++++++-------------------------- gdb/dwarf2/read.h | 5 +++ 3 files changed, 66 insertions(+), 52 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 6cadd33232..625fa3e7ee 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,22 @@ +2020-05-27 Tom Tromey + + * dwarf2/read.h (struct dwarf2_per_objfile) : New + member. + * dwarf2/read.c (delete_file_name_entry): Fix comment. + (create_cu_from_index_list) + (create_signatured_type_table_from_index) + (create_signatured_type_table_from_debug_names) + (dw2_get_file_names_reader, dwarf2_initialize_objfile) + (dwarf2_create_include_psymtab) + (create_debug_type_hash_table, add_type_unit) + (create_type_unit_group, read_comp_units_from_section) + (dwarf2_compute_name, create_cus_hash_table) + (create_dwp_hash_table, create_dwo_unit_in_dwp_v1) + (create_dwo_unit_in_dwp_v2, open_and_init_dwp_file): Use new + obstack. + (dw2_get_real_path): Likewise. Change argument to + dwarf2_per_objfile. + 2020-05-27 Luis Machado PR tdep/26000 diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c index ec3844188e..3996a8a35f 100644 --- a/gdb/dwarf2/read.c +++ b/gdb/dwarf2/read.c @@ -2276,8 +2276,8 @@ delete_file_name_entry (void *e) xfree ((void*) file_data->real_names[i]); } - /* The space for the struct itself lives on objfile_obstack, - so we don't free it here. */ + /* The space for the struct itself lives on the obstack, so we don't + free it here. */ } /* Create a quick_file_names hash table. */ @@ -2408,9 +2408,8 @@ dwarf2_per_objfile::get_tu (int index) return this->all_type_units[index]; } -/* Return a new dwarf2_per_cu_data allocated on OBJFILE's - objfile_obstack, and constructed with the specified field - values. */ +/* Return a new dwarf2_per_cu_data allocated on the dwarf2_per_objfile + obstack, and constructed with the specified field values. */ static dwarf2_per_cu_data * create_cu_from_index_list (struct dwarf2_per_objfile *dwarf2_per_objfile, @@ -2418,16 +2417,15 @@ create_cu_from_index_list (struct dwarf2_per_objfile *dwarf2_per_objfile, int is_dwz, sect_offset sect_off, ULONGEST length) { - struct objfile *objfile = dwarf2_per_objfile->objfile; dwarf2_per_cu_data *the_cu - = OBSTACK_ZALLOC (&objfile->objfile_obstack, + = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct dwarf2_per_cu_data); the_cu->sect_off = sect_off; the_cu->length = length; the_cu->dwarf2_per_objfile = dwarf2_per_objfile; the_cu->section = section; - the_cu->v.quick = OBSTACK_ZALLOC (&objfile->objfile_obstack, - struct dwarf2_per_cu_quick_data); + the_cu->v.quick = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, + struct dwarf2_per_cu_quick_data); the_cu->is_dwz = is_dwz; return the_cu; } @@ -2489,8 +2487,6 @@ create_signatured_type_table_from_index const gdb_byte *bytes, offset_type elements) { - struct objfile *objfile = dwarf2_per_objfile->objfile; - gdb_assert (dwarf2_per_objfile->all_type_units.empty ()); dwarf2_per_objfile->all_type_units.reserve (elements / 3); @@ -2512,7 +2508,7 @@ create_signatured_type_table_from_index signature = extract_unsigned_integer (bytes + 16, 8, BFD_ENDIAN_LITTLE); bytes += 3 * 8; - sig_type = OBSTACK_ZALLOC (&objfile->objfile_obstack, + sig_type = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct signatured_type); sig_type->signature = signature; sig_type->type_offset_in_tu = type_offset_in_tu; @@ -2521,7 +2517,7 @@ create_signatured_type_table_from_index sig_type->per_cu.sect_off = sect_off; sig_type->per_cu.dwarf2_per_objfile = dwarf2_per_objfile; sig_type->per_cu.v.quick - = OBSTACK_ZALLOC (&objfile->objfile_obstack, + = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct dwarf2_per_cu_quick_data); slot = htab_find_slot (sig_types_hash.get (), sig_type, INSERT); @@ -2569,7 +2565,7 @@ create_signatured_type_table_from_debug_names section->buffer + to_underlying (sect_off), rcuh_kind::TYPE); - sig_type = OBSTACK_ZALLOC (&objfile->objfile_obstack, + sig_type = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct signatured_type); sig_type->signature = cu_header.signature; sig_type->type_offset_in_tu = cu_header.type_cu_offset_in_tu; @@ -2578,7 +2574,7 @@ create_signatured_type_table_from_debug_names sig_type->per_cu.sect_off = sect_off; sig_type->per_cu.dwarf2_per_objfile = dwarf2_per_objfile; sig_type->per_cu.v.quick - = OBSTACK_ZALLOC (&objfile->objfile_obstack, + = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct dwarf2_per_cu_quick_data); slot = htab_find_slot (sig_types_hash.get (), sig_type, INSERT); @@ -3088,7 +3084,6 @@ dw2_get_file_names_reader (const struct die_reader_specs *reader, struct dwarf2_per_cu_data *this_cu = cu->per_cu; struct dwarf2_per_objfile *dwarf2_per_objfile = cu->per_cu->dwarf2_per_objfile; - struct objfile *objfile = dwarf2_per_objfile->objfile; struct dwarf2_per_cu_data *lh_cu; struct attribute *attr; void **slot; @@ -3137,7 +3132,7 @@ dw2_get_file_names_reader (const struct die_reader_specs *reader, return; } - qfn = XOBNEW (&objfile->objfile_obstack, struct quick_file_names); + qfn = XOBNEW (&dwarf2_per_objfile->obstack, struct quick_file_names); qfn->hash.dwo_unit = cu->dwo_unit; qfn->hash.line_sect_off = line_offset; gdb_assert (slot != NULL); @@ -3151,7 +3146,8 @@ dw2_get_file_names_reader (const struct die_reader_specs *reader, qfn->num_file_names = offset + lh->file_names_size (); qfn->file_names = - XOBNEWVEC (&objfile->objfile_obstack, const char *, qfn->num_file_names); + XOBNEWVEC (&dwarf2_per_objfile->obstack, const char *, + qfn->num_file_names); if (offset != 0) qfn->file_names[0] = xstrdup (fnd.name); for (int i = 0; i < lh->file_names_size (); ++i) @@ -3192,11 +3188,11 @@ dw2_get_file_names (struct dwarf2_per_cu_data *this_cu) real path for a given file name from the line table. */ static const char * -dw2_get_real_path (struct objfile *objfile, +dw2_get_real_path (struct dwarf2_per_objfile *dwarf2_per_objfile, struct quick_file_names *qfn, int index) { if (qfn->real_names == NULL) - qfn->real_names = OBSTACK_CALLOC (&objfile->objfile_obstack, + qfn->real_names = OBSTACK_CALLOC (&dwarf2_per_objfile->obstack, qfn->num_file_names, const char *); if (qfn->real_names[index] == NULL) @@ -3316,7 +3312,8 @@ dw2_map_symtabs_matching_filename && FILENAME_CMP (lbasename (this_name), name_basename) != 0) continue; - this_real_name = dw2_get_real_path (objfile, file_data, j); + this_real_name = dw2_get_real_path (dwarf2_per_objfile, + file_data, j); if (compare_filenames_for_search (this_real_name, name)) { if (dw2_map_expand_apply (objfile, per_cu, name, real_path, @@ -4599,8 +4596,6 @@ dw_expand_symtabs_matching_file_matcher if (file_matcher == NULL) return; - objfile *const objfile = dwarf2_per_objfile->objfile; - htab_up visited_found (htab_create_alloc (10, htab_hash_pointer, htab_eq_pointer, NULL, xcalloc, xfree)); @@ -4650,7 +4645,8 @@ dw_expand_symtabs_matching_file_matcher true)) continue; - this_real_name = dw2_get_real_path (objfile, file_data, j); + this_real_name = dw2_get_real_path (dwarf2_per_objfile, + file_data, j); if (file_matcher (this_real_name, false)) { per_cu->v.quick->mark = 1; @@ -5873,7 +5869,7 @@ dwarf2_initialize_objfile (struct objfile *objfile, dw_index_kind *index_kind) { dwarf2_per_cu_data *per_cu = dwarf2_per_objfile->get_cutu (i); - per_cu->v.quick = OBSTACK_ZALLOC (&objfile->objfile_obstack, + per_cu->v.quick = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct dwarf2_per_cu_quick_data); } @@ -6074,10 +6070,7 @@ dwarf2_create_include_psymtab (const char *name, dwarf2_psymtab *pst, dwarf2_include_psymtab *subpst = new dwarf2_include_psymtab (name, objfile); if (!IS_ABSOLUTE_PATH (subpst->filename)) - { - /* It shares objfile->objfile_obstack. */ - subpst->dirname = pst->dirname; - } + subpst->dirname = pst->dirname; subpst->dependencies = objfile->partial_symtabs->allocate_dependencies (1); subpst->dependencies[0] = pst; @@ -6235,7 +6228,7 @@ create_debug_type_hash_table (struct dwarf2_per_objfile *dwarf2_per_objfile, if (dwo_file) { sig_type = NULL; - dwo_tu = OBSTACK_ZALLOC (&objfile->objfile_obstack, + dwo_tu = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct dwo_unit); dwo_tu->dwo_file = dwo_file; dwo_tu->signature = header.signature; @@ -6249,7 +6242,7 @@ create_debug_type_hash_table (struct dwarf2_per_objfile *dwarf2_per_objfile, /* N.B.: type_offset is not usable if this type uses a DWO file. The real type_offset is in the DWO file. */ dwo_tu = NULL; - sig_type = OBSTACK_ZALLOC (&objfile->objfile_obstack, + sig_type = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct signatured_type); sig_type->signature = header.signature; sig_type->type_offset_in_tu = header.type_cu_offset_in_tu; @@ -6361,13 +6354,11 @@ static struct signatured_type * add_type_unit (struct dwarf2_per_objfile *dwarf2_per_objfile, ULONGEST sig, void **slot) { - struct objfile *objfile = dwarf2_per_objfile->objfile; - if (dwarf2_per_objfile->all_type_units.size () == dwarf2_per_objfile->all_type_units.capacity ()) ++dwarf2_per_objfile->tu_stats.nr_all_type_units_reallocs; - signatured_type *sig_type = OBSTACK_ZALLOC (&objfile->objfile_obstack, + signatured_type *sig_type = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct signatured_type); dwarf2_per_objfile->all_type_units.push_back (sig_type); @@ -6376,7 +6367,7 @@ add_type_unit (struct dwarf2_per_objfile *dwarf2_per_objfile, ULONGEST sig, if (dwarf2_per_objfile->using_index) { sig_type->per_cu.v.quick = - OBSTACK_ZALLOC (&objfile->objfile_obstack, + OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct dwarf2_per_cu_quick_data); } @@ -7234,18 +7225,17 @@ create_type_unit_group (struct dwarf2_cu *cu, sect_offset line_offset_struct) { struct dwarf2_per_objfile *dwarf2_per_objfile = cu->per_cu->dwarf2_per_objfile; - struct objfile *objfile = dwarf2_per_objfile->objfile; struct dwarf2_per_cu_data *per_cu; struct type_unit_group *tu_group; - tu_group = OBSTACK_ZALLOC (&objfile->objfile_obstack, + tu_group = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct type_unit_group); per_cu = &tu_group->per_cu; per_cu->dwarf2_per_objfile = dwarf2_per_objfile; if (dwarf2_per_objfile->using_index) { - per_cu->v.quick = OBSTACK_ZALLOC (&objfile->objfile_obstack, + per_cu->v.quick = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct dwarf2_per_cu_quick_data); } else @@ -7975,13 +7965,13 @@ read_comp_units_from_section (struct dwarf2_per_objfile *dwarf2_per_objfile, /* Save the compilation unit for later lookup. */ if (cu_header.unit_type != DW_UT_type) { - this_cu = XOBNEW (&objfile->objfile_obstack, + this_cu = XOBNEW (&dwarf2_per_objfile->obstack, struct dwarf2_per_cu_data); memset (this_cu, 0, sizeof (*this_cu)); } else { - auto sig_type = XOBNEW (&objfile->objfile_obstack, + auto sig_type = XOBNEW (&dwarf2_per_objfile->obstack, struct signatured_type); memset (sig_type, 0, sizeof (*sig_type)); sig_type->signature = cu_header.signature; @@ -10136,7 +10126,8 @@ dw2_linkage_name (struct die_info *die, struct dwarf2_cu *cu) For Ada, return the DIE's linkage name rather than the fully qualified name. PHYSNAME is ignored.. - The result is allocated on the objfile_obstack and canonicalized. */ + The result is allocated on the dwarf2_per_objfile obstack and + canonicalized. */ static const char * dwarf2_compute_name (const char *name, @@ -11291,7 +11282,8 @@ create_cus_hash_table (struct dwarf2_per_objfile *dwarf2_per_objfile, if (cus_htab == NULL) cus_htab = allocate_dwo_unit_table (); - dwo_unit = OBSTACK_ZALLOC (&objfile->objfile_obstack, struct dwo_unit); + dwo_unit = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, + struct dwo_unit); *dwo_unit = read_unit; slot = htab_find_slot (cus_htab.get (), dwo_unit, INSERT); gdb_assert (slot != NULL); @@ -11494,7 +11486,7 @@ create_dwp_hash_table (struct dwarf2_per_objfile *dwarf2_per_objfile, pulongest (nr_slots), dwp_file->name); } - htab = OBSTACK_ZALLOC (&objfile->objfile_obstack, struct dwp_hash_table); + htab = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct dwp_hash_table); htab->version = version; htab->nr_columns = nr_columns; htab->nr_units = nr_units; @@ -11691,7 +11683,6 @@ create_dwo_unit_in_dwp_v1 (struct dwarf2_per_objfile *dwarf2_per_objfile, const char *comp_dir, ULONGEST signature, int is_debug_types) { - struct objfile *objfile = dwarf2_per_objfile->objfile; const struct dwp_hash_table *dwp_htab = is_debug_types ? dwp_file->tus : dwp_file->cus; bfd *dbfd = dwp_file->dbfd.get (); @@ -11796,7 +11787,7 @@ create_dwo_unit_in_dwp_v1 (struct dwarf2_per_objfile *dwarf2_per_objfile, virtual_dwo_name.c_str ()); } dwo_file = new struct dwo_file; - dwo_file->dwo_name = objfile->intern (virtual_dwo_name); + dwo_file->dwo_name = dwarf2_per_objfile->objfile->intern (virtual_dwo_name); dwo_file->comp_dir = comp_dir; dwo_file->sections.abbrev = sections.abbrev; dwo_file->sections.line = sections.line; @@ -11825,11 +11816,11 @@ create_dwo_unit_in_dwp_v1 (struct dwarf2_per_objfile *dwarf2_per_objfile, dwo_file = (struct dwo_file *) *dwo_file_slot; } - dwo_unit = OBSTACK_ZALLOC (&objfile->objfile_obstack, struct dwo_unit); + dwo_unit = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct dwo_unit); dwo_unit->dwo_file = dwo_file; dwo_unit->signature = signature; dwo_unit->section = - XOBNEW (&objfile->objfile_obstack, struct dwarf2_section_info); + XOBNEW (&dwarf2_per_objfile->obstack, struct dwarf2_section_info); *dwo_unit->section = sections.info_or_types; /* dwo_unit->{offset,length,type_offset_in_tu} are set later. */ @@ -11890,7 +11881,6 @@ create_dwo_unit_in_dwp_v2 (struct dwarf2_per_objfile *dwarf2_per_objfile, const char *comp_dir, ULONGEST signature, int is_debug_types) { - struct objfile *objfile = dwarf2_per_objfile->objfile; const struct dwp_hash_table *dwp_htab = is_debug_types ? dwp_file->tus : dwp_file->cus; bfd *dbfd = dwp_file->dbfd.get (); @@ -11991,7 +11981,7 @@ create_dwo_unit_in_dwp_v2 (struct dwarf2_per_objfile *dwarf2_per_objfile, virtual_dwo_name.c_str ()); } dwo_file = new struct dwo_file; - dwo_file->dwo_name = objfile->intern (virtual_dwo_name); + dwo_file->dwo_name = dwarf2_per_objfile->objfile->intern (virtual_dwo_name); dwo_file->comp_dir = comp_dir; dwo_file->sections.abbrev = create_dwp_v2_section (dwarf2_per_objfile, &dwp_file->sections.abbrev, @@ -12034,11 +12024,11 @@ create_dwo_unit_in_dwp_v2 (struct dwarf2_per_objfile *dwarf2_per_objfile, dwo_file = (struct dwo_file *) *dwo_file_slot; } - dwo_unit = OBSTACK_ZALLOC (&objfile->objfile_obstack, struct dwo_unit); + dwo_unit = OBSTACK_ZALLOC (&dwarf2_per_objfile->obstack, struct dwo_unit); dwo_unit->dwo_file = dwo_file; dwo_unit->signature = signature; dwo_unit->section = - XOBNEW (&objfile->objfile_obstack, struct dwarf2_section_info); + XOBNEW (&dwarf2_per_objfile->obstack, struct dwarf2_section_info); *dwo_unit->section = create_dwp_v2_section (dwarf2_per_objfile, is_debug_types ? &dwp_file->sections.types @@ -12544,7 +12534,7 @@ open_and_init_dwp_file (struct dwarf2_per_objfile *dwarf2_per_objfile) dwp_file->num_sections = elf_numsections (dwp_file->dbfd); dwp_file->elf_sections = - OBSTACK_CALLOC (&objfile->objfile_obstack, + OBSTACK_CALLOC (&dwarf2_per_objfile->obstack, dwp_file->num_sections, asection *); bfd_map_over_sections (dwp_file->dbfd.get (), diff --git a/gdb/dwarf2/read.h b/gdb/dwarf2/read.h index bd743acc71..8dbda90aa5 100644 --- a/gdb/dwarf2/read.h +++ b/gdb/dwarf2/read.h @@ -126,6 +126,11 @@ private: const dwarf2_debug_sections &names); public: + /* Objects that can be shared across objfiles are stored in this + obstack or on the psymtab obstack, while objects that are + objfile-specific are stored on the objfile obstack. */ + auto_obstack obstack; + dwarf2_section_info info {}; dwarf2_section_info abbrev {}; dwarf2_section_info line {}; -- 2.34.1