FDO patch -- make ic related vars TLS if target allows

[Xinliang David Li]

Hi please review the trivial patch below. It reduces race conditions
in value profiling. Another trivial change (to initialize
function_list struct) is also included.

Bootstrapped and regression tested on x86-64/linux.

Thanks,

David


2011-04-27  Xinliang David Li  <davi...@google.com>

        * tree-profile.c (init_ic_make_global_vars): Set
        tls attribute on ic vars.
        * coverage.c (coverage_end_function): Initialize
        function_list with zero.

Index: coverage.c
===================================================================
--- coverage.c	(revision 172977)
+++ coverage.c	(working copy)
@@ -608,7 +608,7 @@ coverage_end_function (void)
     {
       struct function_list *item;
 
-      item = XNEW (struct function_list);
+      item = XCNEW (struct function_list);
 
       *functions_tail = item;
       functions_tail = &item->next;
Index: tree-profile.c
===================================================================
--- tree-profile.c	(revision 172977)
+++ tree-profile.c	(working copy)
@@ -44,6 +44,8 @@ along with GCC; see the file COPYING3.  
 #include "value-prof.h"
 #include "cgraph.h"
 #include "profile.h"
+#include "target.h"
+#include "output.h"
 
 static GTY(()) tree gcov_type_node;
 static GTY(()) tree gcov_type_tmp_var;
@@ -80,6 +82,10 @@ init_ic_make_global_vars (void)
   TREE_PUBLIC (ic_void_ptr_var) = 0;
   DECL_ARTIFICIAL (ic_void_ptr_var) = 1;
   DECL_INITIAL (ic_void_ptr_var) = NULL;
+  if (targetm.have_tls)
+    DECL_TLS_MODEL (ic_void_ptr_var) =
+      decl_default_tls_model (ic_void_ptr_var);
+
   varpool_finalize_decl (ic_void_ptr_var);
   varpool_mark_needed_node (varpool_node (ic_void_ptr_var));
 
@@ -92,6 +98,10 @@ init_ic_make_global_vars (void)
   TREE_PUBLIC (ic_gcov_type_ptr_var) = 0;
   DECL_ARTIFICIAL (ic_gcov_type_ptr_var) = 1;
   DECL_INITIAL (ic_gcov_type_ptr_var) = NULL;
+  if (targetm.have_tls)
+    DECL_TLS_MODEL (ic_gcov_type_ptr_var) =
+      decl_default_tls_model (ic_gcov_type_ptr_var);
+
   varpool_finalize_decl (ic_gcov_type_ptr_var);
   varpool_mark_needed_node (varpool_node (ic_gcov_type_ptr_var));
 }