[binutils-gdb] Unify the DWARF index holders

[binutils-gdb] Unify the DWARF index holders

[Tom Tromey]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=a827b8ec32f9e0ed10b2bf647ce983db813a3d3c

commit a827b8ec32f9e0ed10b2bf647ce983db813a3d3c
Author: Tom Tromey <tom@tromey.com>
Date:   Mon Nov 22 17:05:55 2021 -0700

    Unify the DWARF index holders
    
    The dwarf2_per_bfd object has a separate field for each possible kind
    of index.  Until an earlier patch in this series, two of these were
    even derived from a common base class, but still had separate slots.
    This patch unifies all the index fields using the common base class
    that was introduced earlier in this series.  This makes it more
    obvious that only a single index can be active at a time, and also
    removes some code from dwarf2_initialize_objfile.

Diff:
---
 gdb/dwarf2/index-write.c |  28 +++++++------
 gdb/dwarf2/read.c        | 107 ++++++++++++++++++++++++-----------------------
 gdb/dwarf2/read.h        |  10 +----
 3 files changed, 72 insertions(+), 73 deletions(-)

diff --git a/gdb/dwarf2/index-write.c b/gdb/dwarf2/index-write.c
index 58b0f0b98e3..b7a2e214f6b 100644
--- a/gdb/dwarf2/index-write.c
+++ b/gdb/dwarf2/index-write.c
@@ -1087,12 +1087,11 @@ write_gdbindex_1 (FILE *out_file,
 /* Write the contents of the internal "cooked" index.  */
 
 static void
-write_cooked_index (dwarf2_per_objfile *per_objfile,
+write_cooked_index (cooked_index_vector *table,
 		    const cu_index_map &cu_index_htab,
 		    struct mapped_symtab *symtab)
 {
-  for (const cooked_index_entry *entry
-	 : per_objfile->per_bfd->cooked_index_table->all_entries ())
+  for (const cooked_index_entry *entry : table->all_entries ())
     {
       const auto it = cu_index_htab.find (entry->per_cu);
       gdb_assert (it != cu_index_htab.cend ());
@@ -1178,13 +1177,14 @@ write_gdbindex (dwarf2_per_objfile *per_objfile, FILE *out_file,
       ++this_counter;
     }
 
-  write_cooked_index (per_objfile, cu_index_htab, &symtab);
+  cooked_index_vector *table
+    = (static_cast<cooked_index_vector *>
+       (per_objfile->per_bfd->index_table.get ()));
+  write_cooked_index (table, cu_index_htab, &symtab);
 
   /* Dump the address map.  */
   data_buf addr_vec;
-  std::vector<addrmap *> addrmaps
-    = per_objfile->per_bfd->cooked_index_table->get_addrmaps ();
-  for (auto map : addrmaps)
+  for (auto map : table->get_addrmaps ())
     write_address_map (map, addr_vec, cu_index_htab);
 
   /* Now that we've processed all symbols we can shrink their cu_indices
@@ -1250,8 +1250,10 @@ write_debug_names (dwarf2_per_objfile *per_objfile,
 			  - per_objfile->per_bfd->tu_stats.nr_tus));
   gdb_assert (types_counter == per_objfile->per_bfd->tu_stats.nr_tus);
 
-  for (const cooked_index_entry *entry
-	 : per_objfile->per_bfd->cooked_index_table->all_entries ())
+  cooked_index_vector *table
+    = (static_cast<cooked_index_vector *>
+       (per_objfile->per_bfd->index_table.get ()));
+  for (const cooked_index_entry *entry : table->all_entries ())
     nametable.insert (entry);
 
   nametable.build ();
@@ -1388,10 +1390,12 @@ write_dwarf_index (dwarf2_per_objfile *per_objfile, const char *dir,
 {
   struct objfile *objfile = per_objfile->objfile;
 
-  if (per_objfile->per_bfd->cooked_index_table == nullptr)
+  cooked_index_vector *table
+    = (static_cast<cooked_index_vector *>
+       (per_objfile->per_bfd->index_table.get ()));
+  if (table == nullptr)
     {
-      if (per_objfile->per_bfd->index_table != nullptr
-	  || per_objfile->per_bfd->debug_names_table != nullptr)
+      if (per_objfile->per_bfd->index_table != nullptr)
 	error (_("Cannot use an index to create the index"));
       error (_("No debugging symbols"));
     }
diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
index aa3bf6e2f25..bb5b636e916 100644
--- a/gdb/dwarf2/read.c
+++ b/gdb/dwarf2/read.c
@@ -2932,7 +2932,8 @@ static void
 dw2_symtab_iter_init (struct dw2_symtab_iterator *iter,
 		      dwarf2_per_objfile *per_objfile,
 		      gdb::optional<block_enum> block_index,
-		      domain_enum domain, offset_type namei)
+		      domain_enum domain, offset_type namei,
+		      mapped_index &index)
 {
   iter->per_objfile = per_objfile;
   iter->block_index = block_index;
@@ -2942,12 +2943,10 @@ dw2_symtab_iter_init (struct dw2_symtab_iterator *iter,
   iter->vec = {};
   iter->length = 0;
 
-  mapped_index *index = per_objfile->per_bfd->index_table.get ();
-
-  gdb_assert (!index->symbol_name_slot_invalid (namei));
-  offset_type vec_idx = index->symbol_vec_index (namei);
+  gdb_assert (!index.symbol_name_slot_invalid (namei));
+  offset_type vec_idx = index.symbol_vec_index (namei);
 
-  iter->vec = offset_view (index->constant_pool.slice (vec_idx));
+  iter->vec = offset_view (index.constant_pool.slice (vec_idx));
   iter->length = iter->vec[0];
 }
 
@@ -3078,8 +3077,9 @@ dwarf2_gdb_index::dump (struct objfile *objfile)
 {
   dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
 
-  gdb_printf (".gdb_index: version %d\n",
-	      per_objfile->per_bfd->index_table->version);
+  mapped_index *index = (static_cast<mapped_index *>
+			 (per_objfile->per_bfd->index_table.get ()));
+  gdb_printf (".gdb_index: version %d\n", index->version);
   gdb_printf ("\n");
 }
 
@@ -3129,7 +3129,9 @@ dwarf2_gdb_index::expand_matching_symbols
 
   const block_enum block_kind = global ? GLOBAL_BLOCK : STATIC_BLOCK;
 
-  mapped_index &index = *per_objfile->per_bfd->index_table;
+  mapped_index &index
+    = (static_cast<mapped_index &>
+       (*per_objfile->per_bfd->index_table.get ()));
 
   const char *match_name = name.ada ().lookup_name ().c_str ();
   auto matcher = [&] (const char *symname)
@@ -3145,7 +3147,8 @@ dwarf2_gdb_index::expand_matching_symbols
       struct dw2_symtab_iterator iter;
       struct dwarf2_per_cu_data *per_cu;
 
-      dw2_symtab_iter_init (&iter, per_objfile, block_kind, domain, namei);
+      dw2_symtab_iter_init (&iter, per_objfile, block_kind, domain, namei,
+			    index);
       while ((per_cu = dw2_symtab_iter_next (&iter, index)) != NULL)
 	dw2_expand_symtabs_matching_one (per_cu, per_objfile, nullptr,
 					 nullptr);
@@ -3967,7 +3970,9 @@ dw2_expand_marked_cus
 {
   offset_type vec_len, vec_idx;
   bool global_seen = false;
-  mapped_index &index = *per_objfile->per_bfd->index_table;
+  mapped_index &index
+    = (static_cast<mapped_index &>
+       (*per_objfile->per_bfd->index_table.get ()));
 
   offset_view vec (index.constant_pool.slice (index.symbol_vec_index (idx)));
   vec_len = vec[0];
@@ -4185,7 +4190,9 @@ dwarf2_gdb_index::expand_symtabs_matching
       return true;
     }
 
-  mapped_index &index = *per_objfile->per_bfd->index_table;
+  mapped_index &index
+    = (static_cast<mapped_index &>
+       (*per_objfile->per_bfd->index_table.get ()));
 
   bool result
     = dw2_expand_symtabs_matching_symbol (index, *lookup_name,
@@ -4683,7 +4690,7 @@ dwarf2_read_debug_names (dwarf2_per_objfile *per_objfile)
 
   create_addrmap_from_aranges (per_objfile, &per_bfd->debug_aranges);
 
-  per_bfd->debug_names_table = std::move (map);
+  per_bfd->index_table = std::move (map);
   per_bfd->quick_file_names_table =
     create_quick_file_names_table (per_bfd->all_comp_units.size ());
 
@@ -5119,7 +5126,9 @@ dwarf2_debug_names_index::expand_matching_symbols
 {
   dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
 
-  mapped_debug_names &map = *per_objfile->per_bfd->debug_names_table;
+  mapped_debug_names &map
+    = (static_cast<mapped_debug_names &>
+       (*per_objfile->per_bfd->index_table.get ()));
   const block_search_flags block_flags
     = global ? SEARCH_GLOBAL_BLOCK : SEARCH_STATIC_BLOCK;
 
@@ -5179,7 +5188,9 @@ dwarf2_debug_names_index::expand_symtabs_matching
       return true;
     }
 
-  mapped_debug_names &map = *per_objfile->per_bfd->debug_names_table;
+  mapped_debug_names &map
+    = (static_cast<mapped_debug_names &>
+       (*per_objfile->per_bfd->index_table.get ()));
 
   bool result
     = dw2_expand_symtabs_matching_symbol (map, *lookup_name,
@@ -5284,38 +5295,20 @@ dwarf2_initialize_objfile (struct objfile *objfile)
       return;
     }
 
-  /* Was a debug names index already read when we processed an objfile sharing
-     PER_BFD?  */
-  if (per_bfd->debug_names_table != nullptr)
-    {
-      dwarf_read_debug_printf ("re-using shared debug names table");
-      objfile->qf.push_front
-	(per_bfd->debug_names_table->make_quick_functions ());
-      return;
-    }
-
   /* Was a GDB index already read when we processed an objfile sharing
      PER_BFD?  */
   if (per_bfd->index_table != nullptr)
     {
-      dwarf_read_debug_printf ("re-using shared index table");
+      dwarf_read_debug_printf ("re-using symbols");
       objfile->qf.push_front (per_bfd->index_table->make_quick_functions ());
       return;
     }
 
-  if (per_bfd->cooked_index_table != nullptr)
-    {
-      dwarf_read_debug_printf ("re-using cooked index table");
-      objfile->qf.push_front
-	(per_bfd->cooked_index_table->make_quick_functions ());
-      return;
-    }
-
   if (dwarf2_read_debug_names (per_objfile))
     {
       dwarf_read_debug_printf ("found debug names");
       objfile->qf.push_front
-	(per_bfd->debug_names_table->make_quick_functions ());
+	(per_bfd->index_table->make_quick_functions ());
       return;
     }
 
@@ -5354,7 +5347,7 @@ dwarf2_build_psymtabs (struct objfile *objfile, bool already_attached)
 
   if (already_attached)
     {
-      if (per_objfile->per_bfd->cooked_index_table != nullptr)
+      if (per_objfile->per_bfd->index_table != nullptr)
 	return;
     }
   else
@@ -7134,11 +7127,11 @@ dwarf2_build_psymtabs_hard (dwarf2_per_objfile *per_objfile)
 		     }),
      indexes.end ());
   indexes.shrink_to_fit ();
-  per_bfd->cooked_index_table.reset
-    (new cooked_index_vector (std::move (indexes)));
 
-  const cooked_index_entry *main_entry
-    = per_bfd->cooked_index_table->get_main ();
+  cooked_index_vector *vec = new cooked_index_vector (std::move (indexes));
+  per_bfd->index_table.reset (vec);
+
+  const cooked_index_entry *main_entry = vec->get_main ();
   if (main_entry != nullptr)
     set_objfile_main_name (objfile, main_entry->name,
 			   main_entry->per_cu->lang);
@@ -18478,12 +18471,14 @@ cooked_index_functions::find_pc_sect_compunit_symtab
       int warn_if_readin)
 {
   dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
-  if (per_objfile->per_bfd->cooked_index_table == nullptr)
+  if (per_objfile->per_bfd->index_table == nullptr)
     return nullptr;
 
   CORE_ADDR baseaddr = objfile->text_section_offset ();
-  dwarf2_per_cu_data *per_cu
-    = per_objfile->per_bfd->cooked_index_table->lookup (pc - baseaddr);
+  cooked_index_vector *table
+    = (static_cast<cooked_index_vector *>
+       (per_objfile->per_bfd->index_table.get ()));
+  dwarf2_per_cu_data *per_cu = table->lookup (pc - baseaddr);
   if (per_cu == nullptr)
     return nullptr;
 
@@ -18507,12 +18502,14 @@ cooked_index_functions::find_compunit_symtab_by_address
     return nullptr;
 
   dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
-  if (per_objfile->per_bfd->cooked_index_table == nullptr)
+  if (per_objfile->per_bfd->index_table == nullptr)
     return nullptr;
 
   CORE_ADDR baseaddr = objfile->data_section_offset ();
-  dwarf2_per_cu_data *per_cu
-    = per_objfile->per_bfd->cooked_index_table->lookup (address - baseaddr);
+  cooked_index_vector *table
+    = (static_cast<cooked_index_vector *>
+       (per_objfile->per_bfd->index_table.get ()));
+  dwarf2_per_cu_data *per_cu = table->lookup (address - baseaddr);
   if (per_cu == nullptr)
     return nullptr;
 
@@ -18528,7 +18525,7 @@ cooked_index_functions::expand_matching_symbols
       symbol_compare_ftype *ordered_compare)
 {
   dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
-  if (per_objfile->per_bfd->cooked_index_table == nullptr)
+  if (per_objfile->per_bfd->index_table == nullptr)
     return;
   const block_search_flags search_flags = (global
 					   ? SEARCH_GLOBAL_BLOCK
@@ -18537,8 +18534,10 @@ cooked_index_functions::expand_matching_symbols
   symbol_name_matcher_ftype *name_match
     = lang->get_symbol_name_matcher (lookup_name);
 
-  for (const cooked_index_entry *entry
-	 : per_objfile->per_bfd->cooked_index_table->all_entries ())
+  cooked_index_vector *table
+    = (static_cast<cooked_index_vector *>
+       (per_objfile->per_bfd->index_table.get ()));
+  for (const cooked_index_entry *entry : table->all_entries ())
     {
       if (entry->parent_entry != nullptr)
 	continue;
@@ -18564,7 +18563,7 @@ cooked_index_functions::expand_symtabs_matching
       enum search_domain kind)
 {
   dwarf2_per_objfile *per_objfile = get_dwarf2_per_objfile (objfile);
-  if (per_objfile->per_bfd->cooked_index_table == nullptr)
+  if (per_objfile->per_bfd->index_table == nullptr)
     return true;
 
   dw_expand_symtabs_matching_file_matcher (per_objfile, file_matcher);
@@ -18602,14 +18601,16 @@ cooked_index_functions::expand_symtabs_matching
     language_ada
   };
 
+  cooked_index_vector *table
+    = (static_cast<cooked_index_vector *>
+       (per_objfile->per_bfd->index_table.get ()));
   for (enum language lang : unique_styles)
     {
       std::vector<gdb::string_view> name_vec
 	= lookup_name_without_params.split_name (lang);
 
-      for (const cooked_index_entry *entry
-	   : per_objfile->per_bfd->cooked_index_table->find (name_vec.back (),
-							     completing))
+      for (const cooked_index_entry *entry : table->find (name_vec.back (),
+							  completing))
 	{
 	  /* No need to consider symbols from expanded CUs.  */
 	  if (per_objfile->symtab_set_p (entry->per_cu))
diff --git a/gdb/dwarf2/read.h b/gdb/dwarf2/read.h
index f3b09c63b64..b58c574c2be 100644
--- a/gdb/dwarf2/read.h
+++ b/gdb/dwarf2/read.h
@@ -441,14 +441,8 @@ public:
      VMA of 0.  */
   bool has_section_at_zero = false;
 
-  /* The mapped index, or NULL if .gdb_index is missing or not being used.  */
-  std::unique_ptr<mapped_index> index_table;
-
-  /* The mapped index, or NULL if .debug_names is missing or not being used.  */
-  std::unique_ptr<mapped_debug_names> debug_names_table;
-
-  /* The cooked index, or NULL if not using one.  */
-  std::unique_ptr<cooked_index_vector> cooked_index_table;
+  /* The mapped index, or NULL in the readnow case.  */
+  std::unique_ptr<dwarf_scanner_base> index_table;
 
   /* When using index_table, this keeps track of all quick_file_names entries.
      TUs typically share line table entries with a CU, so we maintain a