Move line_header_hash to dwarf2_per_objfile

The `line_header_hash` field of `struct dwarf2_per_bfd` contains some
`struct line_header` objects.  A `struct line_header` objects contains
some `file_entry` objects.  A `file_entry` object contains a pointer to
the `symtab` object created from it.  The `line_header_hash` is
therefore ultimately objfile-dependent and can't be shared as-is between
objfiles.

Move it from `dwarf2_per_bfd` to `dwarf2_per_objfile`.

gdb/ChangeLog:

	* dwarf2/read.h (struct dwarf2_per_bfd) <line_header_hash>: Move
	to...
	(struct dwarf2_per_objfile) <line_header_hash>: ... here.
	* dwarf2/read.c (handle_DW_AT_stmt_list): Update.

Change-Id: I8d2ee04df4f4847c2db99061fc976c35af98ac71

3 files changed, 16 insertions, 9 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index a7f989e..589c3f4 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,12 @@
 2020-05-27  Simon Marchi  <simon.marchi@efficios.com>
 
+	* dwarf2/read.h (struct dwarf2_per_bfd) <line_header_hash>: Move
+	to...
+	(struct dwarf2_per_objfile) <line_header_hash>: ... here.
+	* dwarf2/read.c (handle_DW_AT_stmt_list): Update.
+
+2020-05-27  Simon Marchi  <simon.marchi@efficios.com>
+
 	* dwarf2/read.c (struct mapped_index_base) <symbol_name_at,
 	build_name_components, find_name_components_bounds>:
 	Add per_objfile parameter.
diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
index df15068..c77c356 100644
--- a/gdb/dwarf2/read.c
+++ b/gdb/dwarf2/read.c
@@ -10888,10 +10888,10 @@ handle_DW_AT_stmt_list (struct die_info *die, struct dwarf2_cu *cu,
      compile_unit, then use the line header hash table if it's already
      created, but don't create one just yet.  */
 
-  if (dwarf2_per_objfile->per_bfd->line_header_hash == NULL
+  if (dwarf2_per_objfile->line_header_hash == NULL
       && die->tag == DW_TAG_partial_unit)
     {
-      dwarf2_per_objfile->per_bfd->line_header_hash
+      dwarf2_per_objfile->line_header_hash
 	.reset (htab_create_alloc (127, line_header_hash_voidp,
 				   line_header_eq_voidp,
 				   free_line_header_voidp,
@@ -10901,9 +10901,9 @@ handle_DW_AT_stmt_list (struct die_info *die, struct dwarf2_cu *cu,
   line_header_local.sect_off = line_offset;
   line_header_local.offset_in_dwz = cu->per_cu->is_dwz;
   line_header_local_hash = line_header_hash (&line_header_local);
-  if (dwarf2_per_objfile->per_bfd->line_header_hash != NULL)
+  if (dwarf2_per_objfile->line_header_hash != NULL)
     {
-      slot = htab_find_slot_with_hash (dwarf2_per_objfile->per_bfd->line_header_hash.get (),
+      slot = htab_find_slot_with_hash (dwarf2_per_objfile->line_header_hash.get (),
 				       &line_header_local,
 				       line_header_local_hash, NO_INSERT);
 
@@ -10927,11 +10927,11 @@ handle_DW_AT_stmt_list (struct die_info *die, struct dwarf2_cu *cu,
   cu->line_header = lh.release ();
   cu->line_header_die_owner = die;
 
-  if (dwarf2_per_objfile->per_bfd->line_header_hash == NULL)
+  if (dwarf2_per_objfile->line_header_hash == NULL)
     slot = NULL;
   else
     {
-      slot = htab_find_slot_with_hash (dwarf2_per_objfile->per_bfd->line_header_hash.get (),
+      slot = htab_find_slot_with_hash (dwarf2_per_objfile->line_header_hash.get (),
 				       &line_header_local,
 				       line_header_local_hash, INSERT);
       gdb_assert (slot != NULL);
diff --git a/gdb/dwarf2/read.h b/gdb/dwarf2/read.h
index 996cf55..b53aab7 100644
--- a/gdb/dwarf2/read.h
+++ b/gdb/dwarf2/read.h
@@ -234,9 +234,6 @@ public:
   /* The CUs we recently read.  */
   std::vector<dwarf2_per_cu_data *> just_read_cus;
 
-  /* Table containing line_header indexed by offset and offset_in_dwz.  */
-  htab_up line_header_hash;
-
   /* Table containing all filenames.  This is an optional because the
      table is lazily constructed on first access.  */
   gdb::optional<filename_seen_cache> filenames_cache;
@@ -368,6 +365,9 @@ struct dwarf2_per_objfile
      The mapping is done via (CU/TU + DIE offset) -> type.  */
   htab_up die_type_hash;
 
+  /* Table containing line_header indexed by offset and offset_in_dwz.  */
+  htab_up line_header_hash;
+
 private:
   /* Hold the corresponding compunit_symtab for each CU or TU.  This
      is indexed by dwarf2_per_cu_data::index.  A NULL value means