Change section_offsets to a std::vector

This changes section_offsets to be specialization of a std::vector and
updates all the users.  It also removes the ANOFFSET and
SIZEOF_N_SECTION_OFFSETS macros.

Most of this is just a generic sort of cleanup, that reduces the
number of lines of code.  However, a couple spots were doing weird
things.

objfile_relocate did:

-      std::vector<struct section_offsets>
-	new_debug_offsets (SIZEOF_N_SECTION_OFFSETS (debug_objfile->num_sections));

... which seems to greatly over-estimate the number of elements
needed.

This appeared in set_objfile_default_section_offset:

-  std::vector<struct section_offsets> offsets (objf->num_sections,
-					       { { offset } });

... which makes sense due to type safety, but is also actively
confusing given that section_offsets was previously also a kind of
vector type.

Tested on x86-64 Fedora 30.

gdb/ChangeLog
2020-01-08  Tom Tromey  <tromey@adacore.com>

	* xcoffread.c (enter_line_range, read_xcoff_symtab)
	(process_xcoff_symbol, xcoff_symfile_offsets): Update.
	* symtab.h (MSYMBOL_VALUE_ADDRESS): Update.
	(struct section_offsets, ANOFFSET, SIZEOF_N_SECTION_OFFSETS):
	Remove.
	(section_offsets): New typedef.
	* symtab.c (fixup_section, get_msymbol_address): Update.
	* symmisc.c (dump_msymbols): Update.
	* symfile.h (relative_addr_info_to_section_offsets)
	(symfile_map_offsets_to_segments): Update.
	* symfile.c (build_section_addr_info_from_objfile)
	(init_objfile_sect_indices): Update.
	(struct place_section_arg): Change type of "offsets".
	(place_section): Update.
	(relative_addr_info_to_section_offsets): Change type of
	"section_offsets".  Remove "num_sections" parameter.
	(default_symfile_offsets, syms_from_objfile_1)
	(set_objfile_default_section_offset): Update.
	(reread_symbols): No need to preserve section offsets by hand.
	(symfile_map_offsets_to_segments): Change type of "offsets".
	* stap-probe.c (relocate_address): Update.
	* stabsread.h (process_one_symbol): Update.
	* solib-target.c (struct lm_info_target) <offsets>: Change type.
	(solib_target_relocate_section_addresses): Update.
	* solib-svr4.c (enable_break, svr4_relocate_main_executable):
	Update.
	* solib-frv.c (frv_relocate_main_executable): Update.
	* solib-dsbt.c (dsbt_relocate_main_executable): Update.
	* solib-aix.c (solib_aix_get_section_offsets): Change return
	type.
	(solib_aix_solib_create_inferior_hook): Update.
	* remote.c (remote_target::get_offsets): Update.
	* psymtab.c (find_pc_sect_psymtab): Update.
	* psympriv.h (struct partial_symbol) <address, text_low,
	text_high>: Update.
	* objfiles.h (obj_section_offset): Update.
	(struct objfile) <section_offsets>: Change type.
	<num_sections>: Remove.
	(objfile_relocate): Update.
	* objfiles.c (entry_point_address_query): Update
	(relocate_one_symbol): Change type of "section_offsets".
	(objfile_relocate1, objfile_relocate1): Change type of
	"new_offsets".
	(objfile_rebase1): Update.
	* mipsread.c (mipscoff_symfile_read): Update.
	(read_alphacoff_dynamic_symtab): Remove "section_offsets"
	parameter.
	* mdebugread.c (parse_symbol): Change type of "section_offsets".
	(parse_external, psymtab_to_symtab_1): Update.
	* machoread.c (macho_symfile_offsets): Update.
	* ia64-tdep.c (ia64_find_unwind_table): Update.
	* hppa-tdep.c (read_unwind_info): Update.
	* hppa-bsd-tdep.c (hppabsd_find_global_pointer): Update.
	* dwarf2read.c (create_addrmap_from_index)
	(create_addrmap_from_aranges, dw2_find_pc_sect_compunit_symtab)
	(process_psymtab_comp_unit_reader, add_partial_symbol)
	(add_partial_subprogram, process_full_comp_unit)
	(read_file_scope, read_func_scope, read_lexical_block_scope)
	(read_call_site_scope, dwarf2_rnglists_process)
	(dwarf2_ranges_process, dwarf2_ranges_read)
	(dwarf_decode_lines_1, var_decode_location, new_symbol)
	(dwarf2_fetch_die_loc_sect_off, dwarf2_per_cu_text_offset):
	Update.
	* dwarf2-frame.c (execute_cfa_program, dwarf2_frame_find_fde):
	Update.
	* dtrace-probe.c (dtrace_probe::get_relocated_address): Update.
	* dbxread.c (read_dbx_symtab, read_ofile_symtab): Update.
	(process_one_symbol): Change type of "section_offsets".
	* ctfread.c (get_objfile_text_range): Update.
	* coffread.c (coff_symtab_read, enter_linenos)
	(process_coff_symbol): Update.
	* coff-pe-read.c (add_pe_forwarded_sym): Update.
	* amd64-windows-tdep.c (amd64_windows_find_unwind_info): Update.

Change-Id: I147eb967e9b44d82f4048039de7bb44b80cd72fb

1 files changed, 22 insertions, 54 deletions

diff --git a/gdb/symfile.c b/gdb/symfile.c
index 86d6174..0285f8f 100644
--- a/gdb/symfile.c
+++ b/gdb/symfile.c
@@ -269,7 +269,7 @@ build_section_addr_info_from_objfile (const struct objfile *objfile)
     {
       int sectindex = sap[i].sectindex;
 
-      sap[i].addr += objfile->section_offsets->offsets[sectindex];
+      sap[i].addr += objfile->section_offsets[sectindex];
     }
   return sap;
 }
@@ -315,14 +315,14 @@ init_objfile_sect_indices (struct objfile *objfile)
      later, e.g. by the remote qOffsets packet, and then this will
      be wrong!  That's why we try segments first.  */
 
-  for (i = 0; i < objfile->num_sections; i++)
+  for (i = 0; i < objfile->section_offsets.size (); i++)
     {
-      if (ANOFFSET (objfile->section_offsets, i) != 0)
+      if (objfile->section_offsets[i] != 0)
 	{
 	  break;
 	}
     }
-  if (i == objfile->num_sections)
+  if (i == objfile->section_offsets.size ())
     {
       if (objfile->sect_index_text == -1)
 	objfile->sect_index_text = 0;
@@ -339,7 +339,7 @@ init_objfile_sect_indices (struct objfile *objfile)
 
 struct place_section_arg
 {
-  struct section_offsets *offsets;
+  section_offsets *offsets;
   CORE_ADDR lowest;
 };
 
@@ -350,7 +350,8 @@ static void
 place_section (bfd *abfd, asection *sect, void *obj)
 {
   struct place_section_arg *arg = (struct place_section_arg *) obj;
-  CORE_ADDR *offsets = arg->offsets->offsets, start_addr;
+  section_offsets &offsets = *arg->offsets;
+  CORE_ADDR start_addr;
   int done;
   ULONGEST align = ((ULONGEST) 1) << bfd_section_alignment (sect);
 
@@ -408,17 +409,15 @@ place_section (bfd *abfd, asection *sect, void *obj)
 }
 
 /* Store section_addr_info as prepared (made relative and with SECTINDEX
-   filled-in) by addr_info_make_relative into SECTION_OFFSETS of NUM_SECTIONS
-   entries.  */
+   filled-in) by addr_info_make_relative into SECTION_OFFSETS.  */
 
 void
-relative_addr_info_to_section_offsets (struct section_offsets *section_offsets,
-				       int num_sections,
+relative_addr_info_to_section_offsets (section_offsets &section_offsets,
 				       const section_addr_info &addrs)
 {
   int i;
 
-  memset (section_offsets, 0, SIZEOF_N_SECTION_OFFSETS (num_sections));
+  section_offsets.assign (section_offsets.size (), 0);
 
   /* Now calculate offsets for section that were specified by the caller.  */
   for (i = 0; i < addrs.size (); i++)
@@ -432,7 +431,7 @@ relative_addr_info_to_section_offsets (struct section_offsets *section_offsets,
       /* Record all sections in offsets.  */
       /* The section_offsets in the objfile are here filled in using
          the BFD index.  */
-      section_offsets->offsets[osp->sectindex] = osp->addr;
+      section_offsets[osp->sectindex] = osp->addr;
     }
 }
 
@@ -636,12 +635,8 @@ void
 default_symfile_offsets (struct objfile *objfile,
 			 const section_addr_info &addrs)
 {
-  objfile->num_sections = gdb_bfd_count_sections (objfile->obfd);
-  objfile->section_offsets = (struct section_offsets *)
-    obstack_alloc (&objfile->objfile_obstack,
-		   SIZEOF_N_SECTION_OFFSETS (objfile->num_sections));
-  relative_addr_info_to_section_offsets (objfile->section_offsets,
-					 objfile->num_sections, addrs);
+  objfile->section_offsets.resize (gdb_bfd_count_sections (objfile->obfd));
+  relative_addr_info_to_section_offsets (objfile->section_offsets, addrs);
 
   /* For relocatable files, all loadable sections will start at zero.
      The zero is meaningless, so try to pick arbitrary addresses such
@@ -662,11 +657,11 @@ default_symfile_offsets (struct objfile *objfile,
 
       if (cur_sec == NULL)
 	{
-	  CORE_ADDR *offsets = objfile->section_offsets->offsets;
+	  section_offsets &offsets = objfile->section_offsets;
 
 	  /* Pick non-overlapping offsets for sections the user did not
 	     place explicitly.  */
-	  arg.offsets = objfile->section_offsets;
+	  arg.offsets = &objfile->section_offsets;
 	  arg.lowest = 0;
 	  bfd_map_over_sections (objfile->obfd, place_section, &arg);
 
@@ -902,7 +897,7 @@ init_entry_point_info (struct objfile *objfile)
    (as gleaned by GDB's shared library code).  We convert each address
    into an offset from the section VMA's as it appears in the object
    file, and then call the file's sym_offsets function to convert this
-   into a format-specific offset table --- a `struct section_offsets'.
+   into a format-specific offset table --- a `section_offsets'.
    The sectindex field is used to control the ordering of sections
    with the same name.  Upon return, it is updated to contain the
    corresponding BFD section index, or -1 if the section was not found.
@@ -926,13 +921,8 @@ syms_from_objfile_1 (struct objfile *objfile,
       /* No symbols to load, but we still need to make sure
 	 that the section_offsets table is allocated.  */
       int num_sections = gdb_bfd_count_sections (objfile->obfd);
-      size_t size = SIZEOF_N_SECTION_OFFSETS (num_sections);
 
-      objfile->num_sections = num_sections;
-      objfile->section_offsets
-	= (struct section_offsets *) obstack_alloc (&objfile->objfile_obstack,
-						    size);
-      memset (objfile->section_offsets, 0, size);
+      objfile->section_offsets.assign (num_sections, 0);
       return;
     }
 
@@ -2164,8 +2154,7 @@ set_objfile_default_section_offset (struct objfile *objf,
 				    CORE_ADDR offset)
 {
   /* Add OFFSET to all sections by default.  */
-  std::vector<struct section_offsets> offsets (objf->num_sections,
-					       { { offset } });
+  section_offsets offsets (objf->section_offsets.size (), offset);
 
   /* Create sorted lists of all sections in ADDRS as well as all
      sections in OBJF.  */
@@ -2203,11 +2192,11 @@ set_objfile_default_section_offset (struct objfile *objf,
 	}
 
       if (cmp == 0)
-	offsets[objf_sect->sectindex].offsets[0] = 0;
+	offsets[objf_sect->sectindex] = 0;
     }
 
   /* Apply the new section offsets.  */
-  objfile_relocate (objf, offsets.data ());
+  objfile_relocate (objf, offsets);
 }
 
 /* This function allows the addition of incrementally linked object files.
@@ -2479,9 +2468,6 @@ reread_symbols (void)
       new_modtime = new_statbuf.st_mtime;
       if (new_modtime != objfile->mtime)
 	{
-	  struct section_offsets *offsets;
-	  int num_offsets;
-
 	  printf_filtered (_("`%s' has changed; re-reading symbols.\n"),
 			   objfile_name (objfile));
 
@@ -2556,14 +2542,6 @@ reread_symbols (void)
 	    error (_("Can't read symbols from %s: %s."), objfile_name (objfile),
 		   bfd_errmsg (bfd_get_error ()));
 
-	  /* Save the offsets, we will nuke them with the rest of the
-	     objfile_obstack.  */
-	  num_offsets = objfile->num_sections;
-	  offsets = ((struct section_offsets *)
-		     alloca (SIZEOF_N_SECTION_OFFSETS (num_offsets)));
-	  memcpy (offsets, objfile->section_offsets,
-		  SIZEOF_N_SECTION_OFFSETS (num_offsets));
-
 	  objfile->reset_psymtabs ();
 
 	  /* NB: after this call to obstack_free, objfiles_changed
@@ -2595,15 +2573,6 @@ reread_symbols (void)
 
 	  build_objfile_section_table (objfile);
 
-	  /* We use the same section offsets as from last time.  I'm not
-	     sure whether that is always correct for shared libraries.  */
-	  objfile->section_offsets = (struct section_offsets *)
-	    obstack_alloc (&objfile->objfile_obstack,
-			   SIZEOF_N_SECTION_OFFSETS (num_offsets));
-	  memcpy (objfile->section_offsets, offsets,
-		  SIZEOF_N_SECTION_OFFSETS (num_offsets));
-	  objfile->num_sections = num_offsets;
-
 	  /* What the hell is sym_new_init for, anyway?  The concept of
 	     distinguishing between the main file and additional files
 	     in this way seems rather dubious.  */
@@ -3705,7 +3674,7 @@ free_symfile_segment_data (struct symfile_segment_data *data)
 int
 symfile_map_offsets_to_segments (bfd *abfd,
 				 const struct symfile_segment_data *data,
-				 struct section_offsets *offsets,
+				 section_offsets &offsets,
 				 int num_segment_bases,
 				 const CORE_ADDR *segment_bases)
 {
@@ -3737,8 +3706,7 @@ symfile_map_offsets_to_segments (bfd *abfd,
       if (which > num_segment_bases)
         which = num_segment_bases;
 
-      offsets->offsets[i] = (segment_bases[which - 1]
-                             - data->segment_bases[which - 1]);
+      offsets[i] = segment_bases[which - 1] - data->segment_bases[which - 1];
     }
 
   return 1;