Cleanup DECL streaming

[Jan Hubicka]

Hi,
this patch drops DECL_ORIGINAL_TYPE streaming and also logic handling
external decls in blocks since we no longer stream them at all.

Bootstrapped/regtested x86_64-linux, OK?

Honza

	* lto-streamer-out.c (DFS::DFS_write_tree_body): Do not
	stream DECL_ORIGINAL_TYPE.
	(DFS::DFS_write_tree_body): Drop hack handling local external decls.
	(hash_tree): Do not walk DECL_ORIGINAL_TYPE.
	* tree-streamer-in.c (lto_input_ts_decl_non_common_tree_pointers):
	Do not walk original type.
	* tree-streamer-out.c (streamer_write_chain): Drop hack handling
	external decls.
	(write_ts_decl_non_common_tree_pointers): Do not stream
	DECL_ORIGINAL_TYPE
	* tree.c (free_lang_data_in_decl): Clear DECL_ORIGINAL_TYPE.
	(find_decls_types_r): Do not walk DEC_ORIGINAL_TYPE.

Index: lto-streamer-out.c
===================================================================
--- lto-streamer-out.c	(revision 261841)
+++ lto-streamer-out.c	(working copy)
@@ -819,12 +819,6 @@ DFS::DFS_write_tree_body (struct output_
 	DFS_follow_tree_edge (DECL_DEBUG_EXPR (expr));
     }
 
-  if (CODE_CONTAINS_STRUCT (code, TS_DECL_NON_COMMON))
-    {
-      if (TREE_CODE (expr) == TYPE_DECL)
-	DFS_follow_tree_edge (DECL_ORIGINAL_TYPE (expr));
-    }
-
   if (CODE_CONTAINS_STRUCT (code, TS_DECL_WITH_VIS))
     {
       /* Make sure we don't inadvertently set the assembler name.  */
@@ -907,14 +901,13 @@ DFS::DFS_write_tree_body (struct output_
   if (CODE_CONTAINS_STRUCT (code, TS_BLOCK))
     {
       for (tree t = BLOCK_VARS (expr); t; t = TREE_CHAIN (t))
-	if (VAR_OR_FUNCTION_DECL_P (t)
-	    && DECL_EXTERNAL (t))
-	  /* We have to stream externals in the block chain as
-	     non-references.  See also
-	     tree-streamer-out.c:streamer_write_chain.  */
-	  DFS_write_tree (ob, expr_state, t, ref_p, false);
-	else
+	{
+	  /* We would have to stream externals in the block chain as
+	     non-references but we should have dropped them in
+	     free-lang-data.  */
+	  gcc_assert (!VAR_OR_FUNCTION_DECL_P (t) || !DECL_EXTERNAL (t));
 	  DFS_follow_tree_edge (t);
+	}
 
       DFS_follow_tree_edge (BLOCK_SUPERCONTEXT (expr));
 
@@ -1261,12 +1249,6 @@ hash_tree (struct streamer_tree_cache_d
          be able to call get_symbol_initial_value.  */
     }
 
-  if (CODE_CONTAINS_STRUCT (code, TS_DECL_NON_COMMON))
-    {
-      if (code == TYPE_DECL)
-	visit (DECL_ORIGINAL_TYPE (t));
-    }
-
   if (CODE_CONTAINS_STRUCT (code, TS_DECL_WITH_VIS))
     {
       if (DECL_ASSEMBLER_NAME_SET_P (t))
Index: tree-streamer-in.c
===================================================================
--- tree-streamer-in.c	(revision 261841)
+++ tree-streamer-in.c	(working copy)
@@ -728,11 +721,9 @@ lto_input_ts_decl_common_tree_pointers (
    file being read.  */
 
 static void
-lto_input_ts_decl_non_common_tree_pointers (struct lto_input_block *ib,
-					    struct data_in *data_in, tree expr)
+lto_input_ts_decl_non_common_tree_pointers (struct lto_input_block *,
+					    struct data_in *, tree)
 {
-  if (TREE_CODE (expr) == TYPE_DECL)
-    DECL_ORIGINAL_TYPE (expr) = stream_read_tree (ib, data_in);
 }
 
 
Index: tree-streamer-out.c
===================================================================
--- tree-streamer-out.c	(revision 261841)
+++ tree-streamer-out.c	(working copy)
@@ -497,14 +494,10 @@ streamer_write_chain (struct output_bloc
     {
       /* We avoid outputting external vars or functions by reference
 	 to the global decls section as we do not want to have them
-	 enter decl merging.  This is, of course, only for the call
-	 for streaming BLOCK_VARS, but other callers are safe.
-	 See also lto-streamer-out.c:DFS_write_tree_body.  */
-      if (VAR_OR_FUNCTION_DECL_P (t)
-	  && DECL_EXTERNAL (t))
-	stream_write_tree_shallow_non_ref (ob, t, ref_p);
-      else
-	stream_write_tree (ob, t, ref_p);
+	 enter decl merging.  We should not need to do this anymore because
+	 free_lang_data removes them from block scopes.  */
+      gcc_assert (!VAR_OR_FUNCTION_DECL_P (t) || !DECL_EXTERNAL (t));
+      stream_write_tree (ob, t, ref_p);
 
       t = TREE_CHAIN (t);
     }
@@ -620,11 +613,8 @@ write_ts_decl_common_tree_pointers (stru
    pointer fields.  */
 
 static void
-write_ts_decl_non_common_tree_pointers (struct output_block *ob, tree expr,
-				        bool ref_p)
+write_ts_decl_non_common_tree_pointers (struct output_block *, tree, bool)
 {
-  if (TREE_CODE (expr) == TYPE_DECL)
-    stream_write_tree (ob, DECL_ORIGINAL_TYPE (expr), ref_p);
 }
 
 
Index: tree.c
===================================================================
--- tree.c	(revision 261841)
+++ tree.c	(working copy)
@@ -5359,6 +5357,7 @@ free_lang_data_in_decl (tree decl)
       DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT;
       DECL_VISIBILITY_SPECIFIED (decl) = 0;
       DECL_INITIAL (decl) = NULL_TREE;
+      DECL_ORIGINAL_TYPE (decl) = NULL_TREE;
     }
   else if (TREE_CODE (decl) == FIELD_DECL)
     DECL_INITIAL (decl) = NULL_TREE;
@@ -5471,10 +5470,6 @@ find_decls_types_r (tree *tp, int *ws, v
 	  fld_worklist_push (DECL_ARGUMENTS (t), fld);
 	  fld_worklist_push (DECL_RESULT (t), fld);
 	}
-      else if (TREE_CODE (t) == TYPE_DECL)
-	{
-	  fld_worklist_push (DECL_ORIGINAL_TYPE (t), fld);
-	}
       else if (TREE_CODE (t) == FIELD_DECL)
 	{
 	  fld_worklist_push (DECL_FIELD_OFFSET (t), fld);