Fix updating of call_stmt_site_hash

This patch fixes ICE causes by call stmt site hash going out of sync.  For
speculative edges it is assumed to contain a direct call so if we are
removing it hashtable needs to be updated.  I realize that the code is ugly
but I will leave cleanup for next stage1.

Bootstrapped/regtested x86_64-linux. This patch makes it possible to build
Firefox again.

	PR lto/93318
	* cgraph.c (cgraph_edge::resolve_speculation,
	cgraph_edge::redirect_call_stmt_to_callee): Fix update of
	call_stmt_site_hash.

gcc/ChangeLog

+2020-01-18  Jan Hubicka  <hubicka@ucw.cz>
+
+	PR lto/93318	
+	* cgraph.c (cgraph_edge::resolve_speculation,
+	cgraph_edge::redirect_call_stmt_to_callee): Fix update of
+	call_stmt_site_hash.
+
 2020-01-21  Martin Liska  <mliska@suse.cz>
 
 	* config/rs6000/rs6000.c (common_mode_defined): Remove

gcc/cgraph.c

@@ -1248,7 +1248,22 @@ cgraph_edge::resolve_speculation (cgraph_edge *edge, tree callee_decl)
   else
     e2->callee->remove_symbol_and_inline_clones ();
   if (edge->caller->call_site_hash)
-    cgraph_update_edge_in_call_site_hash (edge);
+    {
+      /* We always maintain direct edge in the call site hash, if one
+	 exists.  */
+      if (!edge->num_speculative_call_targets_p ())
+	cgraph_update_edge_in_call_site_hash (edge);
+      else
+	{
+	  cgraph_edge *e;
+	  for (e = edge->caller->callees;
+	       e->call_stmt != edge->call_stmt
+	       || e->lto_stmt_uid != edge->lto_stmt_uid;
+	       e = e->next_callee)
+	    ;
+	  cgraph_update_edge_in_call_site_hash (e);
+	}
+    }
   return edge;
 }
 
@@ -1414,7 +1429,20 @@ cgraph_edge::redirect_call_stmt_to_callee (cgraph_edge *e)
 	  /* Indirect edges are not both in the call site hash.
 	     get it updated.  */
 	  if (e->caller->call_site_hash)
-	    cgraph_update_edge_in_call_site_hash (e2);
+	    {
+	      if (!e2->num_speculative_call_targets_p ())
+		cgraph_update_edge_in_call_site_hash (e2);
+	      else
+		{
+		  cgraph_edge *e;
+		  for (e = e2->caller->callees;
+		       e->call_stmt != e2->call_stmt
+		       || e->lto_stmt_uid != e2->lto_stmt_uid;
+		       e = e->next_callee)
+		    ;
+		  cgraph_update_edge_in_call_site_hash (e);
+		}
+	    }
 	  pop_cfun ();
 	  /* Continue redirecting E to proper target.  */
 	}

gcc/ipa.c

@@ -391,17 +391,20 @@ symbol_table::remove_unreachable_nodes (FILE *file)
 		      n->used_as_abstract_origin = true;
 		}
 	    }
-	  /* If any symbol in a comdat group is reachable, force
-	     all externally visible symbols in the same comdat
+	  /* If any non-external and non-local symbol in a comdat group is
+ 	     reachable, force all externally visible symbols in the same comdat
 	     group to be reachable as well.  Comdat-local symbols
 	     can be discarded if all uses were inlined.  */
-	  if (node->same_comdat_group)
+	  if (node->same_comdat_group
+	      && node->externally_visible
+	      && !DECL_EXTERNAL (node->decl))
 	    {
 	      symtab_node *next;
 	      for (next = node->same_comdat_group;
 		   next != node;
 		   next = next->same_comdat_group)
 		if (!next->comdat_local_p ()
+		    && !DECL_EXTERNAL (next->decl)
 		    && !reachable.add (next))
 		  enqueue_node (next, &first, &reachable);
 	    }