* lto-symtab.c (lto_symtab_entry_def): Add guessed field.

	(lto_symtab_resolve_symbols): Set it.
	(lto_symtab_merge_decls_1): Do not compute used_from_object_file;
	store resolution field in cgraph/varpool.
	* cgraph.c (cgraph_same_body_alias, cgraph_add_thunk): Return node.
	(cgraph_get_node_or_alias, cgraph_get_node_or_alias): Constify.
	(cgraph_dump_node): Drop used_from_object_file.
	(cgraph_clone_node, cgraph_create_virtual_clone): Likewise.
	(cgraph_function_body_availability): Use decl_replaceable_p.
	(cgraph_make_node_local): Set resolution to LDPR_PREVAILING_DEF_IRONLY.
	(cgraph_can_remove_if_no_direct_calls_and_refs): Use
	cgraph_used_from_object_file_p.
	(cgraph_will_be_removed_from_program_if_no_direct_calls): Use
	cgraph_used_from_object_file_p.
	(resolution_used_from_other_file_p): New functoin.
	(cgraph_used_from_object_file_p): New predicate.
	* cgraph.h: Include plugin-api.h
	(struct cgraph_local_info): Remove used_from_object_file.
	(struct cgraph_node): Add resolution field.
	(struct varpool_node): Likewise; remove used_from_object_file;
	reove const_value_known.
	(cgraph_get_node, cgraph_get_node_or_alias, cgraph_node,
	cgraph_same_body_alias, cgraph_add_thunk): Update prototypes.
	(resolution_used_from_other_file_p, cgraph_used_from_object_file_p,
	varpool_used_from_object_file_p): Declare.
	(varpool_get_node, varpool_extra_name_alias): Update prototype.
	* tree.h (DECL_REPLACEABLE_P): Remove.
	(decl_replaceable_p, decl_binds_to_current_def_p): Declare.
	* final.c (rest_of_clean_state): Use decl_binds_to_current_def_p.
	* lto-cgraph.c (lto_output_node, lto_output_varpool_node,
	input_overwrite_node, input_node, input_varpool_node): Stream
	resolution.
	* expr.c (expand_expr_real_1): Use const_value_known_p
	* ipa.c (ipa_discover_readonly_nonaddressable_var): Do not set
	const_value_known.
	(cgraph_externally_visible_p): Use cgraph_used_from_object_file_p.
	(function_and_variable_visibility): Set resolution for local vars
	and functions.
	use varpool_used_from_object_file_p.
	* varasm.c (resolution_to_local_definition_p, resolution_local_p): New
	static functions.
	(default_binds_local_p_1): Use resolutoin info.
	(decl_binds_to_current_def_p, decl_replaceable_p): New functions.
	* varpool.c (varpool_get_node): Constify.
	(const_value_known_p): Do not use vnode->const_value_known;
	use decl_replaceable_p.
	(varpool_finalize_decl): Do not set const_value_known.
	(cgraph_variable_initializer_availability): Use decl_replaceable_p
	(varpool_extra_name_alias): Return new node.
	(varpool_used_from_object_file_p): New function.

	* decl.c (finish_function): Use decl_replaceable_p
	* method.c (make_alias_for_thunk): Update call of cgraph_same_body_alias.

	* lto.c (lto_promote_cross_file_statics): Use const_value_known_p.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@164610 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 26 insertions, 19 deletions

diff --git a/gcc/varpool.c b/gcc/varpool.c
index 673905d5a76..ff3631b3478 100644
--- a/gcc/varpool.c
+++ b/gcc/varpool.c
@@ -107,7 +107,7 @@ eq_varpool_node (const void *p1, const void *p2)
 
 /* Return varpool node assigned to DECL without creating new one.  */
 struct varpool_node *
-varpool_get_node (tree decl)
+varpool_get_node (const_tree decl)
 {
   struct varpool_node key, **slot;
 
@@ -116,7 +116,7 @@ varpool_get_node (tree decl)
 
   if (!varpool_hash)
     return NULL;
-  key.decl = decl;
+  key.decl = CONST_CAST2 (tree, const_tree, decl);
   slot = (struct varpool_node **)
     htab_find_slot (varpool_hash, &key, NO_INSERT);
   if (!slot)
@@ -365,8 +365,6 @@ decide_is_variable_needed (struct varpool_node *node, tree decl)
 bool
 const_value_known_p (tree decl)
 {
-  struct varpool_node *vnode;
-
   if (TREE_CODE (decl) != VAR_DECL
       &&TREE_CODE (decl) != CONST_DECL)
     return false;
@@ -386,21 +384,12 @@ const_value_known_p (tree decl)
 
   gcc_assert (TREE_STATIC (decl) || DECL_EXTERNAL (decl));
 
-  /* In WHOPR mode we can put variable into one partition
-     and make it external in the other partition.  In this
-     case we still know the value, but it can't be determined
-     from DECL flags.  For this reason we keep const_value_known
-     flag in varpool nodes.  */
-  if ((vnode = varpool_get_node (decl))
-      && vnode->const_value_known)
-    return true;
-
   /* Variables declared 'const' without an initializer
      have zero as the initializer if they may not be
      overridden at link or run time.  */
   if (!DECL_INITIAL (decl)
       && (DECL_EXTERNAL (decl)
-	  || DECL_REPLACEABLE_P (decl)))
+	  || decl_replaceable_p (decl)))
     return false;
 
   /* Variables declared `const' with an initializer are considered
@@ -444,7 +433,6 @@ varpool_finalize_decl (tree decl)
      there.  */
   else if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl))
     varpool_mark_needed_node (node);
-  node->const_value_known |= const_value_known_p (node->decl);
   if (cgraph_global_info_ready)
     varpool_assemble_pending_decls ();
 }
@@ -462,7 +450,7 @@ cgraph_variable_initializer_availability (struct varpool_node *node)
   /* If the variable can be overwritten, return OVERWRITABLE.  Takes
      care of at least two notable extensions - the COMDAT variables
      used to share template instantiations in C++.  */
-  if (!(*targetm.binds_local_p) (node->decl) && !DECL_COMDAT (node->decl))
+  if (!decl_replaceable_p (node->decl))
     return AVAIL_OVERWRITABLE;
   return AVAIL_AVAILABLE;
 }
@@ -674,7 +662,7 @@ add_new_static_var (tree type)
 /* Attempt to mark ALIAS as an alias to DECL.  Return TRUE if successful.
    Extra name aliases are output whenever DECL is output.  */
 
-bool
+struct varpool_node *
 varpool_extra_name_alias (tree alias, tree decl)
 {
   struct varpool_node key, *alias_node, *decl_node, **slot;
@@ -695,7 +683,7 @@ varpool_extra_name_alias (tree alias, tree decl)
 
   /* If the varpool_node has been already created, fail.  */
   if (*slot)
-    return false;
+    return NULL;
 
   alias_node = ggc_alloc_cleared_varpool_node ();
   alias_node->decl = alias;
@@ -707,7 +695,26 @@ varpool_extra_name_alias (tree alias, tree decl)
     decl_node->extra_name->prev = alias_node;
   decl_node->extra_name = alias_node;
   *slot = alias_node;
-  return true;
+  return alias_node;
+}
+
+/* Return true when NODE is known to be used from other (non-LTO) object file.
+   Known only when doing LTO via linker plugin.  */
+
+bool
+varpool_used_from_object_file_p (struct varpool_node *node)
+{
+  struct varpool_node *alias;
+
+  if (!TREE_PUBLIC (node->decl))
+    return false;
+  if (resolution_used_from_other_file_p (node->resolution))
+    return true;
+  for (alias = node->extra_name; alias; alias = alias->next)
+    if (TREE_PUBLIC (alias->decl)
+	&& resolution_used_from_other_file_p (alias->resolution))
+      return true;
+  return false;
 }
 
 #include "gt-varpool.h"