Adapt .debug_names writer to new DWARF scanner

This updates the .debug_names writer to work with the new DWARF
scanner.

gdb/dwarf2/index-write.c

@@ -664,15 +664,10 @@ public:
   enum class unit_kind { cu, tu };
 
   /* Insert one symbol.  */
-  void insert (const partial_symbol *psym, int cu_index, bool is_static,
-	       unit_kind kind)
+  void insert (int dwarf_tag, const char *name, int cu_index, bool is_static,
+	       unit_kind kind, enum language lang)
   {
-    const int dwarf_tag = psymbol_tag (psym);
-    if (dwarf_tag == 0)
-      return;
-    const char *name = psym->ginfo.search_name ();
-
-    if (psym->ginfo.language () == language_ada)
+    if (lang == language_ada)
       {
 	/* We want to ensure that the Ada main function's name appears
 	   verbatim in the index.  However, this name will be of the
@@ -715,6 +710,28 @@ public:
     value_set.emplace (symbol_value (dwarf_tag, cu_index, is_static, kind));
   }
 
+  void insert (const partial_symbol *psym, int cu_index, bool is_static,
+	       unit_kind kind)
+  {
+    const int dwarf_tag = psymbol_tag (psym);
+    if (dwarf_tag == 0)
+      return;
+    const char *name = psym->ginfo.search_name ();
+
+    insert (dwarf_tag, name, cu_index, is_static, kind,
+	    psym->ginfo.language ());
+  }
+
+  void insert (const cooked_index_entry *entry)
+  {
+    const auto it = m_cu_index_htab.find (entry->per_cu);
+    gdb_assert (it != m_cu_index_htab.cend ());
+    const char *name = entry->full_name (&m_string_obstack);
+    insert (entry->tag, name, it->second, (entry->flags & IS_STATIC) != 0,
+	    entry->per_cu->is_debug_types ? unit_kind::tu : unit_kind::cu,
+	    entry->per_cu->lang);
+  }
+
   /* Build all the tables.  All symbols must be already inserted.
      This function does not call file_write, caller has to do it
      afterwards.  */
@@ -897,6 +914,11 @@ public:
     m_debugstrlookup.file_write (file_str);
   }
 
+  void add_cu (dwarf2_per_cu_data *per_cu, offset_type index)
+  {
+    m_cu_index_htab.emplace (per_cu, index);
+  }
+
 private:
 
   /* Storage for symbol names mapping them to their .debug_str section
@@ -1211,6 +1233,8 @@ private:
 
   /* Temporary storage for Ada names.  */
   auto_obstack m_string_obstack;
+
+  cu_index_map m_cu_index_htab;
 };
 
 /* Return iff any of the needed offsets does not fit into 32-bit
@@ -1491,17 +1515,20 @@ write_debug_names (dwarf2_per_objfile *per_objfile,
   int types_counter = 0;
   for (int i = 0; i < per_objfile->per_bfd->all_comp_units.size (); ++i)
     {
-      const dwarf2_per_cu_data *per_cu
+      dwarf2_per_cu_data *per_cu
 	= per_objfile->per_bfd->all_comp_units[i].get ();
-      partial_symtab *psymtab = per_cu->v.psymtab;
 
       int &this_counter = per_cu->is_debug_types ? types_counter : counter;
       data_buf &this_list = per_cu->is_debug_types ? types_cu_list : cu_list;
+      partial_symtab *psymtab = (per_objfile->per_bfd->using_index
+				 ? nullptr
+				 : per_cu->v.psymtab);
 
       if (psymtab != nullptr && psymtab->user == nullptr)
 	nametable.recursively_write_psymbols (objfile, psymtab, psyms_seen,
 					      this_counter);
 
+      nametable.add_cu (per_cu, this_counter);
       this_list.append_uint (nametable.dwarf5_offset_size (),
 			     dwarf5_byte_order,
 			     to_underlying (per_cu->sect_off));
@@ -1513,6 +1540,11 @@ 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);
 
+  if (per_objfile->per_bfd->using_index)
+    for (const cooked_index_entry *entry
+	   : per_objfile->per_bfd->cooked_index_table->all_entries ())
+      nametable.insert (entry);
+
   nametable.build ();
 
   /* No addr_vec - DWARF-5 uses .debug_aranges generated by GCC.  */