Introduce partial_symtab::read_symtab method

This introduces a new partial_symtab::read_symtab method, and updates
the symbol readers to subclass partial_symtab and implement this
method.  The old read_symtab and read_symtab_private members are
removed.

In practice, only DWARF and CTF are truly updated to take advantage of
the new setup.  The other symbol readers are less actively maintained,
and so this patch also introduces a "legacy_psymtab", which
essentially works the same way as the old partial_symtab.

(Note that, without more knowledge of the interaction between these
symbol readers, fixing this to remove the new (small) overhead is not
trivial, because these readers copy the read_symtab pointer between
partial symtabs.)

gdb/ChangeLog
2020-01-26  Tom Tromey  <tom@tromey.com>

	* xcoffread.c (this_symtab_psymtab, read_xcoff_symtab)
	(xcoff_psymtab_to_symtab_1, xcoff_read_symtab)
	(xcoff_start_psymtab, xcoff_end_psymtab, scan_xcoff_symtab): Use
	legacy_symtab.
	* stabsread.h (dbx_end_psymtab): Use legacy_symtab.
	* psymtab.c (psymtab_to_symtab): Call method.
	(dump_psymtab): Update.
	* psympriv.h (struct partial_symtab): Add virtual destructor.
	<read_symtab>: New method.
	(struct legacy_symtab): New.
	* mdebugread.c (mdebug_read_symtab): Use legacy_psymtab.
	(struct pst_map) <pst>: Now a legacy_psymtab.
	(parse_procedure, parse_partial_symbols, psymtab_to_symtab_1)
	(new_psymtab): Use legacy_psymtab.
	* dwarf2read.h (struct dwarf2_psymtab): New.
	(struct dwarf2_per_cu_data) <psymtab>: Use it.
	* dwarf2read.c (dwarf2_create_include_psymtab)
	(dwarf2_build_include_psymtabs, create_type_unit_group)
	(create_partial_symtab, process_psymtab_comp_unit_reader)
	(build_type_psymtabs_reader, build_type_psymtab_dependencies)
	(set_partial_user): Use dwarf2_psymtab.
	(dwarf2_psymtab::read_symtab): Rename from dwarf2_read_symtab.
	(psymtab_to_symtab_1, process_full_comp_unit)
	(process_full_type_unit, dwarf2_ranges_read)
	(dwarf2_get_pc_bounds, psymtab_include_file_name)
	(dwarf_decode_lines): Use dwarf2_psymtab.
	* dwarf-index-write.c (psym_index_map): Use dwarf2_psymtab.
	(add_address_entry_worker, write_one_signatured_type)
	(recursively_count_psymbols, recursively_write_psymbols)
	(write_one_signatured_type, psyms_seen_size, write_gdbindex)
	(write_debug_names): Likewise.
	* dbxread.c (struct header_file_location): Take a legacy_psymtab.
	<pst>: Now a legacy_psymtab.
	(find_corresponding_bincl_psymtab): Return a legacy_psymtab.
	(read_dbx_symtab, start_psymtab, dbx_end_psymtab)
	(dbx_psymtab_to_symtab_1, read_ofile_symtab): Use legacy_psymtab.
	* ctfread.c (struct ctf_psymtab): New.
	(ctf_start_symtab, ctf_end_symtab, psymtab_to_symtab): Take a
	ctf_psymtab.
	(ctf_psymtab::read_symtab): Rename from ctf_read_symtab.
	(create_partial_symtab): Return a ctf_psymtab.
	(scan_partial_symbols): Update.

Change-Id: Ia57a828786867d6ad03200af8f996f48ed15285e

1 files changed, 37 insertions, 37 deletions

diff --git a/gdb/dbxread.c b/gdb/dbxread.c
index 4e388fae..64387c6 100644
--- a/gdb/dbxread.c
+++ b/gdb/dbxread.c
@@ -245,7 +245,7 @@ find_text_range (bfd * sym_bfd, struct objfile *objfile)
 struct header_file_location
 {
   header_file_location (const char *name_, int instance_,
-			struct partial_symtab *pst_)
+			legacy_psymtab *pst_)
     : name (name_),
       instance (instance_),
       pst (pst_)
@@ -254,7 +254,7 @@ struct header_file_location
 
   const char *name;		/* Name of header file */
   int instance;			/* See above */
-  struct partial_symtab *pst;	/* Partial symtab that has the
+  legacy_psymtab *pst;	/* Partial symtab that has the
 				   BINCL/EINCL defs for this file.  */
 };
 
@@ -263,16 +263,16 @@ static std::vector<struct header_file_location> *bincl_list;
 
 /* Local function prototypes.  */
 
-static void read_ofile_symtab (struct objfile *, struct partial_symtab *);
+static void read_ofile_symtab (struct objfile *, legacy_psymtab *);
 
-static void dbx_read_symtab (struct partial_symtab *self,
+static void dbx_read_symtab (legacy_psymtab *self,
 			     struct objfile *objfile);
 
-static void dbx_psymtab_to_symtab_1 (struct objfile *, struct partial_symtab *);
+static void dbx_psymtab_to_symtab_1 (struct objfile *, legacy_psymtab *);
 
 static void read_dbx_symtab (minimal_symbol_reader &, struct objfile *);
 
-static struct partial_symtab *find_corresponding_bincl_psymtab (const char *,
+static legacy_psymtab *find_corresponding_bincl_psymtab (const char *,
 								int);
 
 static const char *dbx_next_symbol_text (struct objfile *);
@@ -297,7 +297,7 @@ static void add_old_header_file (const char *, int);
 
 static void add_this_object_header_file (int);
 
-static struct partial_symtab *start_psymtab (struct objfile *, const char *,
+static legacy_psymtab *start_psymtab (struct objfile *, const char *,
 					     CORE_ADDR, int);
 
 /* Free up old header file tables.  */
@@ -857,7 +857,7 @@ dbx_next_symbol_text (struct objfile *objfile)
    bincl in the list.  Return the partial symtab associated
    with that header_file_location.  */
 
-static struct partial_symtab *
+static legacy_psymtab *
 find_corresponding_bincl_psymtab (const char *name, int instance)
 {
   for (const header_file_location &bincl : *bincl_list)
@@ -866,7 +866,7 @@ find_corresponding_bincl_psymtab (const char *name, int instance)
       return bincl.pst;
 
   repeated_header_complaint (name, symnum);
-  return (struct partial_symtab *) 0;
+  return (legacy_psymtab *) 0;
 }
 
 /* Set namestring based on nlist.  If the string table index is invalid, 
@@ -968,7 +968,7 @@ read_dbx_symtab (minimal_symbol_reader &reader, struct objfile *objfile)
   int data_sect_index;
 
   /* Current partial symtab.  */
-  struct partial_symtab *pst;
+  legacy_psymtab *pst;
 
   /* List of current psymtab's include files.  */
   const char **psymtab_include_list;
@@ -976,7 +976,7 @@ read_dbx_symtab (minimal_symbol_reader &reader, struct objfile *objfile)
   int includes_used;
 
   /* Index within current psymtab dependency list.  */
-  struct partial_symtab **dependency_list;
+  legacy_psymtab **dependency_list;
   int dependencies_used, dependencies_allocated;
 
   text_addr = DBX_TEXT_ADDR (objfile);
@@ -989,7 +989,7 @@ read_dbx_symtab (minimal_symbol_reader &reader, struct objfile *objfile)
 
   stringtab_global = DBX_STRINGTAB (objfile);
 
-  pst = (struct partial_symtab *) 0;
+  pst = (legacy_psymtab *) 0;
 
   includes_allocated = 30;
   includes_used = 0;
@@ -999,8 +999,8 @@ read_dbx_symtab (minimal_symbol_reader &reader, struct objfile *objfile)
   dependencies_allocated = 30;
   dependencies_used = 0;
   dependency_list =
-    (struct partial_symtab **) alloca (dependencies_allocated *
-				       sizeof (struct partial_symtab *));
+    (legacy_psymtab **) alloca (dependencies_allocated *
+				sizeof (legacy_psymtab *));
 
   /* Init bincl list */
   std::vector<struct header_file_location> bincl_storage;
@@ -1136,7 +1136,7 @@ read_dbx_symtab (minimal_symbol_reader &reader, struct objfile *objfile)
 				   ? nlist.n_value : pst->raw_text_high (),
 				   dependency_list, dependencies_used,
 				   textlow_not_set);
-		  pst = (struct partial_symtab *) 0;
+		  pst = (legacy_psymtab *) 0;
 		  includes_used = 0;
 		  dependencies_used = 0;
 		  has_line_numbers = 0;
@@ -1251,7 +1251,7 @@ read_dbx_symtab (minimal_symbol_reader &reader, struct objfile *objfile)
 				      ? valu : pst->raw_text_high ()),
 				     dependency_list, dependencies_used,
 				     prev_textlow_not_set);
-		    pst = (struct partial_symtab *) 0;
+		    pst = (legacy_psymtab *) 0;
 		    includes_used = 0;
 		    dependencies_used = 0;
 		    has_line_numbers = 0;
@@ -1762,7 +1762,7 @@ read_dbx_symtab (minimal_symbol_reader &reader, struct objfile *objfile)
 	  /* Find the corresponding bincl and mark that psymtab on the
 	     psymtab dependency list.  */
 	  {
-	    struct partial_symtab *needed_pst =
+	    legacy_psymtab *needed_pst =
 	      find_corresponding_bincl_psymtab (namestring, nlist.n_value);
 
 	    /* If this include file was defined earlier in this file,
@@ -1789,15 +1789,15 @@ read_dbx_symtab (minimal_symbol_reader &reader, struct objfile *objfile)
 		dependency_list[dependencies_used++] = needed_pst;
 		if (dependencies_used >= dependencies_allocated)
 		  {
-		    struct partial_symtab **orig = dependency_list;
+		    legacy_psymtab **orig = dependency_list;
 
 		    dependency_list =
-		      (struct partial_symtab **)
+		      (legacy_psymtab **)
 		      alloca ((dependencies_allocated *= 2)
-			      * sizeof (struct partial_symtab *));
+			      * sizeof (legacy_psymtab *));
 		    memcpy (dependency_list, orig,
 			    (dependencies_used
-			     * sizeof (struct partial_symtab *)));
+			     * sizeof (legacy_psymtab *)));
 #ifdef DEBUG_INFO
 		    fprintf_unfiltered (gdb_stderr,
 					"Had to reallocate "
@@ -1823,7 +1823,7 @@ read_dbx_symtab (minimal_symbol_reader &reader, struct objfile *objfile)
 			       symnum * symbol_size,
 			       (CORE_ADDR) 0, dependency_list,
 			       dependencies_used, textlow_not_set);
-	      pst = (struct partial_symtab *) 0;
+	      pst = (legacy_psymtab *) 0;
 	      includes_used = 0;
 	      dependencies_used = 0;
 	      has_line_numbers = 0;
@@ -1899,17 +1899,16 @@ read_dbx_symtab (minimal_symbol_reader &reader, struct objfile *objfile)
    is the address relative to which its symbols are (incremental) or 0
    (normal).  */
 
-static struct partial_symtab *
+static legacy_psymtab *
 start_psymtab (struct objfile *objfile, const char *filename, CORE_ADDR textlow,
 	       int ldsymoff)
 {
-  struct partial_symtab *result = new partial_symtab (filename, objfile,
-						      textlow);
+  legacy_psymtab *result = new legacy_psymtab (filename, objfile, textlow);
 
   result->read_symtab_private =
     XOBNEW (&objfile->objfile_obstack, struct symloc);
   LDSYMOFF (result) = ldsymoff;
-  result->read_symtab = dbx_read_symtab;
+  result->legacy_read_symtab = dbx_read_symtab;
   SYMBOL_SIZE (result) = symbol_size;
   SYMBOL_OFFSET (result) = symbol_table_offset;
   STRING_OFFSET (result) = string_table_offset;
@@ -1927,11 +1926,11 @@ start_psymtab (struct objfile *objfile, const char *filename, CORE_ADDR textlow,
 
    FIXME:  List variables and peculiarities of same.  */
 
-struct partial_symtab *
-dbx_end_psymtab (struct objfile *objfile, struct partial_symtab *pst,
+legacy_psymtab *
+dbx_end_psymtab (struct objfile *objfile, legacy_psymtab *pst,
 		 const char **include_list, int num_includes,
 		 int capping_symbol_offset, CORE_ADDR capping_text,
-		 struct partial_symtab **dependency_list,
+		 legacy_psymtab **dependency_list,
 		 int number_dependencies,
 		 int textlow_not_set)
 {
@@ -2017,15 +2016,15 @@ dbx_end_psymtab (struct objfile *objfile, struct partial_symtab *pst,
       pst->dependencies
 	= objfile->partial_symtabs->allocate_dependencies (number_dependencies);
       memcpy (pst->dependencies, dependency_list,
-	      number_dependencies * sizeof (struct partial_symtab *));
+	      number_dependencies * sizeof (legacy_psymtab *));
     }
   else
     pst->dependencies = 0;
 
   for (i = 0; i < num_includes; i++)
     {
-      struct partial_symtab *subpst =
-	new partial_symtab (include_list[i], objfile);
+      legacy_psymtab *subpst =
+	new legacy_psymtab (include_list[i], objfile);
 
       subpst->read_symtab_private =
 	XOBNEW (&objfile->objfile_obstack, struct symloc);
@@ -2039,7 +2038,7 @@ dbx_end_psymtab (struct objfile *objfile, struct partial_symtab *pst,
       subpst->dependencies[0] = pst;
       subpst->number_of_dependencies = 1;
 
-      subpst->read_symtab = pst->read_symtab;
+      subpst->legacy_read_symtab = pst->legacy_read_symtab;
     }
 
   if (num_includes == 0
@@ -2065,7 +2064,7 @@ dbx_end_psymtab (struct objfile *objfile, struct partial_symtab *pst,
 }
 
 static void
-dbx_psymtab_to_symtab_1 (struct objfile *objfile, struct partial_symtab *pst)
+dbx_psymtab_to_symtab_1 (struct objfile *objfile, legacy_psymtab *pst)
 {
   int i;
 
@@ -2092,7 +2091,8 @@ dbx_psymtab_to_symtab_1 (struct objfile *objfile, struct partial_symtab *pst)
 	    wrap_here ("");	/* Flush output.  */
 	    gdb_flush (gdb_stdout);
 	  }
-	dbx_psymtab_to_symtab_1 (objfile, pst->dependencies[i]);
+	dbx_psymtab_to_symtab_1 (objfile,
+				 (legacy_psymtab *) pst->dependencies[i]);
       }
 
   if (LDSYMLEN (pst))		/* Otherwise it's a dummy.  */
@@ -2115,7 +2115,7 @@ dbx_psymtab_to_symtab_1 (struct objfile *objfile, struct partial_symtab *pst)
    Be verbose about it if the user wants that.  SELF is not NULL.  */
 
 static void
-dbx_read_symtab (struct partial_symtab *self, struct objfile *objfile)
+dbx_read_symtab (legacy_psymtab *self, struct objfile *objfile)
 {
   if (self->readin)
     {
@@ -2165,7 +2165,7 @@ dbx_read_symtab (struct partial_symtab *self, struct objfile *objfile)
 /* Read in a defined section of a specific object file's symbols.  */
 
 static void
-read_ofile_symtab (struct objfile *objfile, struct partial_symtab *pst)
+read_ofile_symtab (struct objfile *objfile, legacy_psymtab *pst)
 {
   const char *namestring;
   struct external_nlist *bufp;