From 57d63ce2b971db198ce135553354e2a5f2ae4a01 Mon Sep 17 00:00:00 2001 From: Doug Evans Date: Fri, 27 Sep 2013 18:48:41 +0000 Subject: [PATCH] * dwarf2read.c (struct dwo_file): Add/tweak comments. (lookup_dwo_unit_in_dwp): Renamed from lookup_dwo_in_dwp. Remove arg "htab". All callers updated. (create_debug_types_hash_table): Remove redundant copy of abbrev_section. (create_dwo_in_dwp): Tweak comments. (read_str_index): Tweak comment. Record dwarf form name in static local. --- gdb/ChangeLog | 11 ++++++ gdb/dwarf2read.c | 88 ++++++++++++++++++++++++++---------------------- 2 files changed, 58 insertions(+), 41 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index b777d5faa5..5822149fb8 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,14 @@ +2013-09-27 Doug Evans + + * dwarf2read.c (struct dwo_file): Add/tweak comments. + (lookup_dwo_unit_in_dwp): Renamed from lookup_dwo_in_dwp. Remove + arg "htab". All callers updated. + (create_debug_types_hash_table): Remove redundant copy of + abbrev_section. + (create_dwo_in_dwp): Tweak comments. + (read_str_index): Tweak comment. Record dwarf form name in static + local. + 2013-09-27 Pedro Alves * remote.h (REMOTE_SYSROOT_PREFIX): New define. diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c index be2093ab18..c112693626 100644 --- a/gdb/dwarf2read.c +++ b/gdb/dwarf2read.c @@ -750,8 +750,15 @@ struct dwo_unit }; /* Data for one DWO file. - This includes virtual DWO files that have been packaged into a - DWP file. */ + + This includes virtual DWO files (a virtual DWO file is a DWO file as it + appears in a DWP file). DWP files don't really have DWO files per se - + comdat folding of types "loses" the DWO file they came from, and from + a high level view DWP files appear to contain a mass of random types. + However, to maintain consistency with the non-DWP case we pretend DWP + files contain virtual DWO files, and we assign each TU with one virtual + DWO file (generally based on the line and abbrev section offsets - + a heuristic that seems to work in practice). */ struct dwo_file { @@ -830,7 +837,7 @@ struct dwp_file /* Section info for this file. */ struct dwp_sections sections; - /* Table of CUs in the file. */ + /* Table of CUs in the file. */ const struct dwp_hash_table *cus; /* Table of TUs in the file. */ @@ -1699,9 +1706,9 @@ static htab_t allocate_signatured_type_table (struct objfile *objfile); static htab_t allocate_dwo_unit_table (struct objfile *objfile); -static struct dwo_unit *lookup_dwo_in_dwp - (struct dwp_file *dwp_file, const struct dwp_hash_table *htab, - const char *comp_dir, ULONGEST signature, int is_debug_types); +static struct dwo_unit *lookup_dwo_unit_in_dwp + (struct dwp_file *dwp_file, const char *comp_dir, + ULONGEST signature, int is_debug_types); static struct dwp_file *get_dwp_file (void); @@ -4238,7 +4245,6 @@ create_debug_types_hash_table (struct dwo_file *dwo_file, { bfd *abfd; const gdb_byte *info_ptr, *end_ptr; - struct dwarf2_section_info *abbrev_section; dwarf2_read_section (objfile, section); info_ptr = section->buffer; @@ -4250,11 +4256,6 @@ create_debug_types_hash_table (struct dwo_file *dwo_file, not present, in which case section->asection will be NULL. */ abfd = section->asection->owner; - if (dwo_file) - abbrev_section = &dwo_file->sections.abbrev; - else - abbrev_section = &dwarf2_per_objfile->abbrev; - /* We don't use init_cutu_and_read_dies_simple, or some such, here because we don't need to read any dies: the signature is in the header. */ @@ -4551,8 +4552,8 @@ lookup_dwp_signatured_type (struct dwarf2_cu *cu, ULONGEST sig) Try the DWP file and hope for the best. */ if (dwp_file->tus == NULL) return NULL; - dwo_entry = lookup_dwo_in_dwp (dwp_file, dwp_file->tus, NULL, - sig, 1 /* is_debug_types */); + dwo_entry = lookup_dwo_unit_in_dwp (dwp_file, NULL, + sig, 1 /* is_debug_types */); if (dwo_entry == NULL) return NULL; @@ -9219,8 +9220,8 @@ create_dwo_in_dwp (struct dwp_file *dwp_file, The DWP file can be made up of a random collection of CUs and TUs. However, for each CU + set of TUs that came from the same original DWO - file, we want to combine them back into a virtual DWO file to save space - (fewer struct dwo_file objects to allocated). Remember that for really + file, we can combine them back into a virtual DWO file to save space + (fewer struct dwo_file objects to allocate). Remember that for really large apps there can be on the order of 8K CUs and 200K TUs, or more. */ virtual_dwo_name = @@ -9255,12 +9256,13 @@ create_dwo_in_dwp (struct dwp_file *dwp_file, dwo_file->sections.str_offsets = sections.str_offsets; /* The "str" section is global to the entire DWP file. */ dwo_file->sections.str = dwp_file->sections.str; - /* The info or types section is assigned later to dwo_unit, + /* The info or types section is assigned below to dwo_unit, there's no need to record it in dwo_file. Also, we can't simply record type sections in dwo_file because we record a pointer into the vector in dwo_unit. As we collect more types we'll grow the vector and eventually have to reallocate space - for it, invalidating all the pointers into the current copy. */ + for it, invalidating all copies of pointers into the previous + contents. */ *dwo_file_slot = dwo_file; } else @@ -9280,21 +9282,22 @@ create_dwo_in_dwp (struct dwp_file *dwp_file, dwo_unit->section = obstack_alloc (&objfile->objfile_obstack, sizeof (struct dwarf2_section_info)); *dwo_unit->section = sections.info_or_types; - /* offset, length, type_offset_in_tu are set later. */ + /* dwo_unit->{offset,length,type_offset_in_tu} are set later. */ return dwo_unit; } -/* Lookup the DWO with SIGNATURE in DWP_FILE. */ +/* Lookup the DWO unit with SIGNATURE in DWP_FILE. + Returns NULL if the signature isn't found. */ static struct dwo_unit * -lookup_dwo_in_dwp (struct dwp_file *dwp_file, - const struct dwp_hash_table *htab, - const char *comp_dir, - ULONGEST signature, int is_debug_types) +lookup_dwo_unit_in_dwp (struct dwp_file *dwp_file, const char *comp_dir, + ULONGEST signature, int is_debug_types) { + const struct dwp_hash_table *dwp_htab = + is_debug_types ? dwp_file->tus : dwp_file->cus; bfd *dbfd = dwp_file->dbfd; - uint32_t mask = htab->nr_slots - 1; + uint32_t mask = dwp_htab->nr_slots - 1; uint32_t hash = signature & mask; uint32_t hash2 = ((signature >> 32) & mask) | 1; unsigned int i; @@ -9309,18 +9312,19 @@ lookup_dwo_in_dwp (struct dwp_file *dwp_file, return *slot; /* Use a for loop so that we don't loop forever on bad debug info. */ - for (i = 0; i < htab->nr_slots; ++i) + for (i = 0; i < dwp_htab->nr_slots; ++i) { ULONGEST signature_in_table; signature_in_table = - read_8_bytes (dbfd, htab->hash_table + hash * sizeof (uint64_t)); + read_8_bytes (dbfd, dwp_htab->hash_table + hash * sizeof (uint64_t)); if (signature_in_table == signature) { - uint32_t section_index = - read_4_bytes (dbfd, htab->unit_table + hash * sizeof (uint32_t)); + uint32_t unit_index = + read_4_bytes (dbfd, + dwp_htab->unit_table + hash * sizeof (uint32_t)); - *slot = create_dwo_in_dwp (dwp_file, htab, section_index, + *slot = create_dwo_in_dwp (dwp_file, dwp_htab, unit_index, comp_dir, signature, is_debug_types); return *slot; } @@ -9756,8 +9760,8 @@ lookup_dwo_cutu (struct dwarf2_per_cu_data *this_unit, if (dwp_htab != NULL) { struct dwo_unit *dwo_cutu = - lookup_dwo_in_dwp (dwp_file, dwp_htab, comp_dir, - signature, is_debug_types); + lookup_dwo_unit_in_dwp (dwp_file, comp_dir, + signature, is_debug_types); if (dwo_cutu != NULL) { @@ -15436,7 +15440,8 @@ dwarf2_read_addr_index (struct dwarf2_per_cu_data *per_cu, return read_addr_index_1 (addr_index, addr_base, addr_size); } -/* Given a DW_AT_str_index, fetch the string. */ +/* Given a DW_FORM_GNU_str_index, fetch the string. + This is only used by the Fission support. */ static const char * read_str_index (const struct die_reader_specs *reader, @@ -15448,21 +15453,22 @@ read_str_index (const struct die_reader_specs *reader, struct dwo_sections *sections = &reader->dwo_file->sections; const gdb_byte *info_ptr; ULONGEST str_offset; + static const char form_name[] = "DW_FORM_GNU_str_index"; dwarf2_read_section (objfile, §ions->str); dwarf2_read_section (objfile, §ions->str_offsets); if (sections->str.buffer == NULL) - error (_("DW_FORM_str_index used without .debug_str.dwo section" + error (_("%s used without .debug_str.dwo section" " in CU at offset 0x%lx [in module %s]"), - (long) cu->header.offset.sect_off, dwo_name); + form_name, (long) cu->header.offset.sect_off, dwo_name); if (sections->str_offsets.buffer == NULL) - error (_("DW_FORM_str_index used without .debug_str_offsets.dwo section" + error (_("%s used without .debug_str_offsets.dwo section" " in CU at offset 0x%lx [in module %s]"), - (long) cu->header.offset.sect_off, dwo_name); + form_name, (long) cu->header.offset.sect_off, dwo_name); if (str_index * cu->header.offset_size >= sections->str_offsets.size) - error (_("DW_FORM_str_index pointing outside of .debug_str_offsets.dwo" + error (_("%s pointing outside of .debug_str_offsets.dwo" " section in CU at offset 0x%lx [in module %s]"), - (long) cu->header.offset.sect_off, dwo_name); + form_name, (long) cu->header.offset.sect_off, dwo_name); info_ptr = (sections->str_offsets.buffer + str_index * cu->header.offset_size); if (cu->header.offset_size == 4) @@ -15470,9 +15476,9 @@ read_str_index (const struct die_reader_specs *reader, else str_offset = bfd_get_64 (abfd, info_ptr); if (str_offset >= sections->str.size) - error (_("Offset from DW_FORM_str_index pointing outside of" + error (_("Offset from %s pointing outside of" " .debug_str.dwo section in CU at offset 0x%lx [in module %s]"), - (long) cu->header.offset.sect_off, dwo_name); + form_name, (long) cu->header.offset.sect_off, dwo_name); return (const char *) (sections->str.buffer + str_offset); } -- 2.34.1