Make cgraph_edge::uid really unique.

2018-06-08  Martin Liska  <mliska@suse.cz>

	* cgraph.c (symbol_table::create_edge): Always assign a new
	unique number.
	(symbol_table::free_edge): Do not recycle numbers.
	* cgraph.h (cgraph_edge::get): New method.
	* symbol-summary.h (symtab_removal): Use it.
	(symtab_duplication): Likewise.
	(call_summary::hashable_uid): Remove.

From-SVN: r261319

gcc/ChangeLog

 2018-06-08  Martin Liska  <mliska@suse.cz>
 
+	* cgraph.c (symbol_table::create_edge): Always assign a new
+	unique number.
+	(symbol_table::free_edge): Do not recycle numbers.
+	* cgraph.h (cgraph_edge::get): New method.
+	* symbol-summary.h (symtab_removal): Use it.
+	(symtab_duplication): Likewise.
+	(call_summary::hashable_uid): Remove.
+
+2018-06-08  Martin Liska  <mliska@suse.cz>
+
 	* ipa-inline-analysis.c (inline_edge_removal_hook): Remove.
 	(initialize_growth_caches): Remove.
 	(free_growth_caches): Likewise.

gcc/cgraph.c

@@ -850,13 +850,12 @@ symbol_table::create_edge (cgraph_node *caller, cgraph_node *callee,
       free_edges = NEXT_FREE_EDGE (edge);
     }
   else
-    {
-      edge = ggc_alloc<cgraph_edge> ();
-      edge->uid = edges_max_uid++;
-    }
+    edge = ggc_alloc<cgraph_edge> ();
 
   edges_count++;
 
+  gcc_assert (++edges_max_uid != 0);
+  edge->m_uid = edges_max_uid;
   edge->aux = NULL;
   edge->caller = caller;
   edge->callee = callee;
@@ -1010,14 +1009,11 @@ cgraph_edge::remove_caller (void)
 void
 symbol_table::free_edge (cgraph_edge *e)
 {
-  int uid = e->uid;
-
   if (e->indirect_info)
     ggc_free (e->indirect_info);
 
   /* Clear out the edge so we do not dangle pointers.  */
   memset (e, 0, sizeof (*e));
-  e->uid = uid;
   NEXT_FREE_EDGE (e) = free_edges;
   free_edges = e;
   edges_count--;

gcc/cgraph.h

@@ -1626,6 +1626,7 @@ struct GTY(()) cgraph_indirect_call_info
 struct GTY((chain_next ("%h.next_caller"), chain_prev ("%h.prev_caller"),
 	    for_user)) cgraph_edge {
   friend class cgraph_node;
+  friend class symbol_table;
 
   /* Remove the edge in the cgraph.  */
   void remove (void);
@@ -1689,6 +1690,12 @@ struct GTY((chain_next ("%h.next_caller"), chain_prev ("%h.prev_caller"),
   /* Return true if the call can be hot.  */
   bool maybe_hot_p (void);
 
+  /* Get unique identifier of the edge.  */
+  inline int get_uid ()
+  {
+    return m_uid;
+  }
+
   /* Rebuild cgraph edges for current function node.  This needs to be run after
      passes that don't update the cgraph.  */
   static unsigned int rebuild_edges (void);
@@ -1716,8 +1723,6 @@ struct GTY((chain_next ("%h.next_caller"), chain_prev ("%h.prev_caller"),
   /* The stmt_uid of call_stmt.  This is used by LTO to recover the call_stmt
      when the function is serialized in.  */
   unsigned int lto_stmt_uid;
-  /* Unique id of the edge.  */
-  int uid;
   /* Whether this edge was made direct by indirect inlining.  */
   unsigned int indirect_inlining_edge : 1;
   /* Whether this edge describes an indirect call with an undetermined
@@ -1761,6 +1766,9 @@ struct GTY((chain_next ("%h.next_caller"), chain_prev ("%h.prev_caller"),
   /* Expected frequency of executions within the function.  */
   sreal sreal_frequency ();
 private:
+  /* Unique id of the edge.  */
+  int m_uid;
+
   /* Remove the edge from the list of the callers of the callee.  */
   void remove_caller (void);
 
@@ -2011,7 +2019,7 @@ public:
   friend class cgraph_node;
   friend class cgraph_edge;
 
-  symbol_table (): cgraph_max_uid (1)
+  symbol_table (): cgraph_max_uid (1), edges_max_uid (1)
   {
   }
 

gcc/symbol-summary.h

@@ -375,19 +375,19 @@ public:
      If a summary for an edge does not exist, it will be created.  */
   T* get_create (cgraph_edge *edge)
   {
-    return get (hashable_uid (edge), true);
+    return get (edge->get_uid (), true);
   }
 
   /* Getter for summary callgraph edge pointer.  */
   T* get (cgraph_edge *edge)
   {
-    return get (hashable_uid (edge), false);
+    return get (edge->get_uid (), false);
   }
 
   /* Remove edge from summary.  */
   void remove (cgraph_edge *edge)
   {
-    int uid = hashable_uid (edge);
+    int uid = edge->get_uid ();
     T **v = m_map.get (uid);
     if (v)
       {
@@ -405,7 +405,7 @@ public:
   /* Return true if a summary for the given EDGE already exists.  */
   bool exists (cgraph_edge *edge)
   {
-    return m_map.get (hashable_uid (edge)) != NULL;
+    return m_map.get (edge->get_uid ()) != NULL;
   }
 
   /* Symbol removal hook that is registered to symbol table.  */
@@ -428,13 +428,6 @@ private:
   /* Getter for summary callgraph ID.  */
   T *get (int uid, bool lazy_insert);
 
-  /* Get a hashable uid of EDGE.  */
-  int hashable_uid (cgraph_edge *edge)
-  {
-    /* Edge uids start at zero which our hash_map does not like.  */
-    return edge->uid + 1;
-  }
-
   /* Main summary store, where summary ID is used as key.  */
   hash_map <map_hash, T *> m_map;
   /* Internal summary removal hook pointer.  */
@@ -511,7 +504,7 @@ call_summary<T *>::symtab_removal (cgraph_edge *edge, void *data)
 {
   call_summary *summary = (call_summary <T *> *) (data);
 
-  int h_uid = summary->hashable_uid (edge);
+  int h_uid = edge->get_uid ();
   T **v = summary->m_map.get (h_uid);
 
   if (v)
@@ -534,7 +527,7 @@ call_summary<T *>::symtab_duplication (cgraph_edge *edge1,
     edge1_summary = summary->get_create (edge1);
   else
     {
-      T **v = summary->m_map.get (summary->hashable_uid (edge1));
+      T **v = summary->m_map.get (edge1->get_uid ());
       if (v)
 	{
 	  /* This load is necessary, because we insert a new value!  */
@@ -545,7 +538,7 @@ call_summary<T *>::symtab_duplication (cgraph_edge *edge1,
   if (edge1_summary)
     {
       T *duplicate = summary->allocate_new ();
-      summary->m_map.put (summary->hashable_uid (edge2), duplicate);
+      summary->m_map.put (edge2->get_uid (), duplicate);
       summary->duplicate (edge1, edge2, edge1_summary, duplicate);
     }
 }