[C++ PATCH] Kill IDENTIFIER_LABEL_VALUE

https://gcc.gnu.org/ml/gcc-patches/2017-10/msg01854.html
	Kill IDENTIFIER_LABEL_VALUE.
	* cp-tree.h (lang_identifier): Delete label_value slot.
	(IDENTIFIER_LABEL_VALUE, SET_IDENTIFIER_LABEL_VALUE): Delete.
	(struct named_label_hasher): Rename to ...
	(struct named_label_hash): ... here.  Reimplement.
	(struct language_function): Adjust x_named_labels.
	* name-lookup.h (struct cp_label_binding): Delete.
	(struct cp_binding_level): Delete shadowed_labels slot.
	* decl.c (struct named_label_entry): Add name and outer slots.
	(pop_label): Rename to ...
	(check_label_used): ... here.  Don't pop.
	(note_label, sort_labels): Delete.
	(pop_labels, pop_local_label): Reimplement.
	(poplevel): Pop local labels as any other decl. Remove
	shadowed_labels handling.
	(named_label_hash::hash, named_label_hash::equal): New.
	(make_label_decl): Absorb into ...
	(lookup_label_1): ... here.  Add making_local_p arg, reimplement.
	(lookup_label, declare_local_label): Adjust.
	(check_goto, define_label): Adjust.
	* lex.c (make_conv_op_name): Don't clear IDENTIFIER_LABEL_VALUE.
	* ptree.c (cxx_print_identifier): Don't print identifier binding.

From-SVN: r254087

gcc/cp/ChangeLog

 2017-10-25  Nathan Sidwell  <nathan@acm.org>
 
+	Kill IDENTIFIER_LABEL_VALUE.
+	* cp-tree.h (lang_identifier): Delete label_value slot.
+	(IDENTIFIER_LABEL_VALUE, SET_IDENTIFIER_LABEL_VALUE): Delete.
+	(struct named_label_hasher): Rename to ...
+	(struct named_label_hash): ... here.  Reimplement.
+	(struct language_function): Adjust x_named_labels.
+	* name-lookup.h (struct cp_label_binding): Delete.
+	(struct cp_binding_level): Delete shadowed_labels slot.
+	* decl.c (struct named_label_entry): Add name and outer slots.
+	(pop_label): Rename to ...
+	(check_label_used): ... here.  Don't pop.
+	(note_label, sort_labels): Delete.
+	(pop_labels, pop_local_label): Reimplement.
+	(poplevel): Pop local labels as any other decl. Remove
+	shadowed_labels handling.
+	(named_label_hash::hash, named_label_hash::equal): New.
+	(make_label_decl): Absorb into ...
+	(lookup_label_1): ... here.  Add making_local_p arg, reimplement.
+	(lookup_label, declare_local_label): Adjust.
+	(check_goto, define_label): Adjust.
+	* lex.c (make_conv_op_name): Don't clear IDENTIFIER_LABEL_VALUE.
+	* ptree.c (cxx_print_identifier): Don't print identifier binding.
+
 	* decl.c (identifier_goto): Reduce duplication.
 	(check_previous_goto_1): Likewise.
 	(check_goto): Move var decls to initialization.

gcc/cp/cp-tree.h

@@ -561,7 +561,6 @@ extern GTY(()) tree cp_global_trees[CPTI_MAX];
 struct GTY(()) lang_identifier {
   struct c_common_identifier c_common;
   cxx_binding *bindings;
-  tree label_value;
 };
 
 /* Return a typed pointer version of T if it designates a
@@ -996,11 +995,6 @@ enum GTY(()) abstract_class_use {
 #define SET_IDENTIFIER_TYPE_VALUE(NODE,TYPE) (TREE_TYPE (NODE) = (TYPE))
 #define IDENTIFIER_HAS_TYPE_VALUE(NODE) (IDENTIFIER_TYPE_VALUE (NODE) ? 1 : 0)
 
-#define IDENTIFIER_LABEL_VALUE(NODE) \
-  (LANG_IDENTIFIER_CAST (NODE)->label_value)
-#define SET_IDENTIFIER_LABEL_VALUE(NODE, VALUE)   \
-  IDENTIFIER_LABEL_VALUE (NODE) = (VALUE)
-
 /* Kinds of identifiers.  Values are carefully chosen.  */
 enum cp_identifier_kind {
   cik_normal = 0,	/* Not a special identifier.  */
@@ -1662,12 +1656,22 @@ struct cxx_int_tree_map_hasher : ggc_ptr_hash<cxx_int_tree_map>
   static bool equal (cxx_int_tree_map *, cxx_int_tree_map *);
 };
 
-struct named_label_entry;
+struct named_label_entry; /* Defined in decl.c.  */
 
-struct named_label_hasher : ggc_ptr_hash<named_label_entry>
+struct named_label_hash : ggc_remove <named_label_entry *>
 {
-  static hashval_t hash (named_label_entry *);
-  static bool equal (named_label_entry *, named_label_entry *);
+  typedef named_label_entry *value_type;
+  typedef tree compare_type; /* An identifier.  */
+
+  inline static hashval_t hash (value_type);
+  inline static bool equal (const value_type, compare_type);
+
+  inline static void mark_empty (value_type &p) {p = NULL;}
+  inline static bool is_empty (value_type p) {return !p;}
+
+  /* Nothing is deletable.  Everything is insertable.  */
+  inline static bool is_deleted (value_type) { return false; }
+  inline static void mark_deleted (value_type) { gcc_unreachable (); }
 };
 
 /* Global state pertinent to the current function.  */
@@ -1696,7 +1700,8 @@ struct GTY(()) language_function {
 
   BOOL_BITFIELD invalid_constexpr : 1;
 
-  hash_table<named_label_hasher> *x_named_labels;
+  hash_table<named_label_hash> *x_named_labels;
+
   cp_binding_level *bindings;
   vec<tree, va_gc> *x_local_names;
   /* Tracking possibly infinite loops.  This is a vec<tree> only because

gcc/cp/lex.c

@@ -585,7 +585,6 @@ make_conv_op_name (tree type)
 
       /* Just in case something managed to bind.  */
       IDENTIFIER_BINDING (identifier) = NULL;
-      IDENTIFIER_LABEL_VALUE (identifier) = NULL_TREE;
 
       /* Hang TYPE off the identifier so it can be found easily later
 	 when performing conversions.  */

gcc/cp/name-lookup.h

@@ -148,15 +148,6 @@ struct GTY(()) cp_class_binding {
   tree identifier;
 };
 
-
-struct GTY(()) cp_label_binding {
-  /* The bound LABEL_DECL.  */
-  tree label;
-  /* The previous IDENTIFIER_LABEL_VALUE.  */
-  tree prev_value;
-};
-
-
 /* For each binding contour we allocate a binding_level structure
    which records the names defined in that contour.
    Contours include:
@@ -202,10 +193,6 @@ struct GTY(()) cp_binding_level {
       the class.  */
   tree type_shadowed;
 
-  /* Similar to class_shadowed, but for IDENTIFIER_LABEL_VALUE, and
-      used for all binding levels.  */
-  vec<cp_label_binding, va_gc> *shadowed_labels;
-
   /* For each level (except not the global one),
       a chain of BLOCK nodes for all the levels
       that were entered and exited one level down.  */

gcc/cp/ptree.c

@@ -177,7 +177,6 @@ cxx_print_identifier (FILE *file, tree node, int indent)
     indent_to (file, indent + 4);
   fprintf (file, "%s local bindings <%p>", get_identifier_kind_name (node),
 	   (void *) IDENTIFIER_BINDING (node));
-  print_node (file, "label", IDENTIFIER_LABEL_VALUE (node), indent + 4);
 }
 
 void