[PATCH 16/18] make TS_IDENTIFIER be a substructure of TS_BASE

[Nathan Froyd]

Now that we've done the requisite surgery on the C++ FE, we can
eliminate TREE_CHAIN and TREE_TYPE from IDENTIFIER_NODEs.  Doing so
turns up a couple different places that need to be tweaked.

The bit I'm not quite sure about is free_lang_data_in_decl and
find_decls_types_r.  Previously, due to C++ FE machinations, we'd free
REAL_IDENTIFIER_TYPE_VALUE naturally, through punning of TREE_TYPE.  Now
that we've shuffled that field into lang_identifier, that bit of
identifiers won't get freed...and I don't know if that causes problems.
Anybody more knowledgeable than I willing to weigh in on that?

-Nathan

gcc/
	* print-tree.c (print_node): Check for TS_TYPED structures before
	accessing TREE_TYPE.
	* tree.h (struct tree_identifier): Inherit from tree_base, not
	tree_common.
	(HT_IDENT_TO_GCC_IDENT): Adjust for said change.
	* tree.c (initialize_tree_contains_struct): Mark TS_IDENTIFIER as
	TS_BASE instead of TS_COMMON.
	(free_lang_data_in_decl): Don't set TREE_TYPE of DECL_NAME.
	(find_decls_types_r): Check for TS_TYPED structures before accessing
	TREE_TYPE.
	* varasm.c (assemble_name): Remove assert.

gcc/c-family/
	* c-common.h (struct c_common_identifier): Inherit from tree_base,
	not tree_common.

diff --git a/gcc/c-family/c-common.h b/gcc/c-family/c-common.h
index e7fe209..961dea7 100644
--- a/gcc/c-family/c-common.h
+++ b/gcc/c-family/c-common.h
@@ -306,7 +306,7 @@ enum c_tree_index
 /* Identifier part common to the C front ends.  Inherits from
    tree_identifier, despite appearances.  */
 struct GTY(()) c_common_identifier {
-  struct tree_common common;
+  struct tree_base base;
   struct cpp_hashnode node;
 };
 
diff --git a/gcc/print-tree.c b/gcc/print-tree.c
index d8acd1b..1a1e33f 100644
--- a/gcc/print-tree.c
+++ b/gcc/print-tree.c
@@ -321,7 +321,7 @@ print_node (FILE *file, const char *prefix, tree node, int indent)
       if (indent <= 4)
 	print_node_brief (file, "type", TREE_TYPE (node), indent + 4);
     }
-  else
+  else if (CODE_CONTAINS_STRUCT (code, TS_TYPED))
     {
       print_node (file, "type", TREE_TYPE (node), indent + 4);
       if (TREE_TYPE (node))
diff --git a/gcc/tree.c b/gcc/tree.c
index 81ee05e..001e8c8 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -366,6 +366,7 @@ initialize_tree_contains_struct (void)
       switch (ts_code)
 	{
 	case TS_TYPED:
+	case TS_IDENTIFIER:
 	  MARK_TS_BASE (code);
 	  break;
 
@@ -383,7 +384,6 @@ initialize_tree_contains_struct (void)
 	  MARK_TS_TYPED (code);
 	  break;
 
-	case TS_IDENTIFIER:
 	case TS_DECL_MINIMAL:
 	case TS_TYPE:
 	case TS_LIST:
@@ -4495,10 +4495,6 @@ free_lang_data_in_decl (tree decl)
   TREE_LANG_FLAG_5 (decl) = 0;
   TREE_LANG_FLAG_6 (decl) = 0;
 
-  /* Identifiers need not have a type.  */
-  if (DECL_NAME (decl))
-    TREE_TYPE (DECL_NAME (decl)) = NULL_TREE;
-
   free_lang_data_in_one_sizepos (&DECL_SIZE (decl));
   free_lang_data_in_one_sizepos (&DECL_SIZE_UNIT (decl));
   if (TREE_CODE (decl) == FIELD_DECL)
@@ -4795,7 +4791,8 @@ find_decls_types_r (tree *tp, int *ws, void *data)
       fld_worklist_push (BLOCK_ABSTRACT_ORIGIN (t), fld);
     }
 
-  fld_worklist_push (TREE_TYPE (t), fld);
+  if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_TYPED))
+    fld_worklist_push (TREE_TYPE (t), fld);
 
   return NULL_TREE;
 }
diff --git a/gcc/tree.h b/gcc/tree.h
index c81186a..f4d18f8 100644
--- a/gcc/tree.h
+++ b/gcc/tree.h
@@ -1529,11 +1529,11 @@ struct GTY(()) tree_vector {
    pointer, and vice versa.  */
 
 #define HT_IDENT_TO_GCC_IDENT(NODE) \
-  ((tree) ((char *) (NODE) - sizeof (struct tree_common)))
+  ((tree) ((char *) (NODE) - sizeof (struct tree_base)))
 #define GCC_IDENT_TO_HT_IDENT(NODE) (&((struct tree_identifier *) (NODE))->id)
 
 struct GTY(()) tree_identifier {
-  struct tree_common common;
+  struct tree_base base;
   struct ht_identifier id;
 };
 
diff --git a/gcc/varasm.c b/gcc/varasm.c
index 76675cd..4c429de 100644
--- a/gcc/varasm.c
+++ b/gcc/varasm.c
@@ -2300,7 +2300,6 @@ assemble_name (FILE *file, const char *name)
       ultimate_transparent_alias_target (&id);
       if (id != id_orig)
 	name = IDENTIFIER_POINTER (id);
-      gcc_assert (! TREE_CHAIN (id));
     }
 
   assemble_name_raw (file, name);
-- 
1.7.0.4